cholecalciferol and Prostatic-Neoplasms

Topics: Cholecalciferol; Dietary Supplements; Humans; Male; Prostatic Neoplasms; Vitamin D; Vitamins

Since the discovery of 1α,25(OH)2D3 in the early 1970s, it has been widely accepted that this metabolite is responsible for the biological actions of vitamin D. Likewise, we have assumed that 25(OH)-19-nor-D3-dependent growth inhibition of human prostate PZ-HPV-7 cells was the result of its subsequent conversion to 1α,25(OH)2-19-nor-D3, catalyzed by CYP27B1 within the prostate cells. However, further in vitro studies in a reconstituted system using recombinant CYP27B1 revealed that 25(OH)-19-nor-D3 was hardly converted to 1α,25(OH)2-19-nor-D3 by the enzyme. The kinetic analysis of 1α-hydroxylation of 25(OH)D3 and 25(OH)-19-nor-D3 demonstrated that the k(cat)/K(m) for 25(OH)-19-nor-D3 is less than 0.1% of that for 25(OH)D3. When 25(OH)-19-nor-D3 was added to cultured PZ-HPV-7 cells, eight metabolites were detected, while no 1α,25(OH)2-19-nor-D3 was found. In addition, the time course of VDR translocation into the nucleus induced by 100 nM 25(OH)-19-nor-D3, and the subsequent transactivation of CYP24A1 gene were almost identical to those induced by 1 nM 1α,25(OH)2-19-nor-D3. These results strongly suggest that 25(OH)-19-nor-D3 binds directly to VDR as a ligand to transport VDR into the nucleus to induce CYP24A1 gene transactivation. Furthermore, knockdown of CYP27B1 gene did not affect the antiproliferative activity of 25(OH)-19-nor-D3, whereas VDR knockdown attenuated the effect, suggesting that the antiproliferative activity of 25(OH)-19-nor-D3 is VDR dependent but CYP27B1 independent. Finally, our recent studies using the same cell line demonstrate that 25(OH)D3 can act as a VDR agonist to induce gene transactivation. These findings suggest that vitamin D analogs without 1α-hydroxyl group could be developed as drugs for osteoporosis or cancer treatment.

Topics: Antineoplastic Agents; Cell Proliferation; Cholecalciferol; Humans; Male; Molecular Structure; Prostatic Neoplasms; Receptors, Calcitriol

Vitamin D is not really a vitamin but the precursor to the potent steroid hormone calcitriol, which has widespread actions throughout the body. Calcitriol regulates numerous cellular pathways that could have a role in determining cancer risk and prognosis. Although epidemiological and early clinical trials are inconsistent, and randomized control trials in humans do not yet exist to conclusively support a beneficial role for vitamin D, accumulating results from preclinical and some clinical studies strongly suggest that vitamin D deficiency increases the risk of developing cancer and that avoiding deficiency and adding vitamin D supplements might be an economical and safe way to reduce cancer incidence and improve cancer prognosis and outcome.

Topics: 25-Hydroxyvitamin D3 1-alpha-Hydroxylase; Breast Neoplasms; Calcitriol; Cholecalciferol; Colonic Neoplasms; Disease Progression; Endocrine System; Female; Humans; Male; Neoplasms; Neoplastic Stem Cells; Polymorphism, Genetic; Prognosis; Prostatic Neoplasms; Randomized Controlled Trials as Topic; Risk; Signal Transduction; Steroid Hydroxylases; Vitamin D; Vitamin D Deficiency; Vitamin D3 24-Hydroxylase

To evaluate the objective clinical response and the safety of the combined administration of somatostatin, melatonin, retinoids, vitamin D3, dopamine subtype 2 receptor (D2R) agonists and low doses of cyclophosphamide, associated with androgen ablation, in patients with a histological diagnosis of prostate adenocarcinoma (Pac).. The clinical data of 30 patients with non-invasive and metastatic prostate cancer, who attended our institution over a period of more than 5 years, were retrospectively reviewed.. 16 patients satisfied the evaluation criteria. Median age: 64 years. Disease stages: 8 patients (50%) were in Stage II. For advanced stages (Stage IV), secondary lesions were located in the bones and lymph nodes. Taken together, an overall objective response (OR) [Complete response (CR) + Partial Response (PR)] was achieved in 69% of the patients, with 88% of objective clinical benefit [CR+PR+SD]. For local Prostate Cancer group, an OR was achieved in 87.5% of patients (7 cases; 53-98; 95% CI), with CR in 62.5% (5 cases, 31-86; 95% CI). In metastatic disease, the OR was 50% (4 cases; 21-78; 95% CI), with a 20% of CR (2 cases; 7-59; 95% CI) and 75% of clinical benefit.. This preliminary study shows that patients with early and advanced forms of prostate cancer, not previously treated by surgery and/or chemo-radiotherapy, can achieve a more than positive clinical benefit with the protocol foreseen by the Di Bella Method. Further clinical investigations are strongly recommended.

Topics: Adult; Aged; Antineoplastic Combined Chemotherapy Protocols; Cholecalciferol; Cyclophosphamide; Dopamine Agonists; Humans; Male; Melatonin; Middle Aged; Pilot Projects; Prostatic Neoplasms; Retinoids; Retrospective Studies; Somatostatin; Treatment Outcome

Vitamin D promotes the differentiation of prostate cancer cells, raising the possibility that vitamin D deficiency over time may contribute to the progression from subclinical prostate cancer to clinical disease. Since low-risk prostate cancers are monitored over time in an effort to determine which progress into clinically important, more aggressive cancers, they provide an excellent model in which to study, over an extended period of time, the effects of enhancing vitamin D status and related changes in tumor progression. This is particularly relevant to African-American men, who exhibit a high prevalence of vitamin D deficiency as well as higher incidence of prostate cancer and higher mortality rates from prostate cancer than Caucasians. Our research team has recently completed an open-label clinical trial aimed at assessing the safety and potential efficacy of vitamin D3 supplementation at 4000 international units (IU) per day for one year in subjects diagnosed with early stage, low-risk prostate cancer. The results of this clinical study suggest that supplementation with vitamin D3 at 4000IU per day may benefit patients with early stage, low-risk prostate cancer on active surveillance, because of the improved outcome (a decreased number of positive cores at repeat biopsy) in more than half of the subjects enrolled in the trial. We also observed that, after one year of supplementation, there was no difference in circulating levels of vitamin D between African-American and Caucasian subjects who completed the study. These clinical results also suggest that robust and sustained vitamin D3 supplementation can reduce prostate cancer-related health disparities in African-American men and that these health disparities are at least in part the result of widespread hypovitaminosis D within the African-American population. This article is part of a Special Issue entitled 'Vitamin D Workshop'.

Topics: Black or African American; Cholecalciferol; Clinical Trials as Topic; Dietary Supplements; Healthcare Disparities; Humans; Male; Prostatic Neoplasms; Risk; Vitamin D; Vitamin D Deficiency

Vitamin D3 deficiency is rampant which may contribute to increased risk of many diseases including cancer, cardiovascular disease and autoimmune disorders. Genomic activity of the active metabolite 1,25-dihydroxyvitamin D (1,25D) mediates most vitamin D3's actions and many gene targets of 1,25D have been characterized. As the importance of non-coding RNAs has emerged, the ability of vitamin D3via 1,25D to regulate microRNAs (miRNAs) has been demonstrated in several cancer cell lines, patient tissue and sera. In vitamin D3 intervention patient trials, significant differences in miRNAs are observed between treatment groups and/or between baseline and followup. In patient sera from population studies, specific miRNA differences associate with serum levels of 25D. The findings thus far indicate that dietary vitamin D3 in patients and 1,25D in vitro not only regulate specific miRNA(s), but may also globally upregulate miRNA levels. This article is part of a Special Issue entitled 'Vitamin D Workshop'.

Topics: Breast Neoplasms; Calcitriol; Cholecalciferol; Colonic Neoplasms; Female; Humans; Leukemia; Male; Melanoma; MicroRNAs; Neoplasms; Prostatic Neoplasms

Prostate cancer (PCa) is the second most common cancer in men worldwide. Epidemiological, molecular, and cellular studies have implicated vitamin D deficiency as a risk factor for the development and/or progression of PCa. Studies using cell culture systems and animal models suggest that vitamin D acts to reduce the growth of PCa through regulation of cellular proliferation and differentiation. However, although preclinical studies provide a strong indication for anti-cancer activity, proof of therapeutic benefits in men is still lacking. The anti-proliferative and pro-differentiating properties of vitamin D have been attributed to calcitriol [1,25(OH)(2)D(3)], the hormonally active form of vitamin D, acting through the vitamin D receptor (VDR). Metabolism of vitamin D in target tissues is mediated by two key enzymes: 1α-hydroxylase (CYP27B1), which catalyzes the synthesis of calcitriol from 25(OH)D and 24-hydroxylase (CYP24), which catalyzes the initial step in the conversion of calcitriol to less active metabolites. Many factors affect the balance of calcitriol synthesis and catabolism and several maneuvers, like combination therapy of calcitriol with other drugs, have been explored to treat PCa and reduce its risk. The current paper is an overview addressing some of the key factors that influence the biological actions of vitamin D and its metabolites in the treatment and/or prevention of PCa.

Topics: 25-Hydroxyvitamin D3 1-alpha-Hydroxylase; Animals; Anti-Inflammatory Agents, Non-Steroidal; Calcitriol; Cholecalciferol; Clinical Trials as Topic; Drug Therapy, Combination; Humans; Isoflavones; Male; Mice; Prostatic Neoplasms; Receptors, Calcitriol; Risk Factors; Steroid Hydroxylases; Vitamin D; Vitamin D Deficiency; Vitamin D3 24-Hydroxylase

Isoflavonoids exert a regulatory function on the expression of cytochrome P450 enzymes and also up-regulate the vitamin D(3) receptor (VDR) on cancer cells, which increase their sensitivity to 1,25-dihydroxyvitamin D(3) , the hormonally active form of vitamin D(3) . Isoflavonoids are also able to raise the serum level of the active form of vitamin D(3) due to their inhibitory activity on CYP24, the enzyme involved in the degradation of 1,25-dihydroxyvitamin D(3) and its precursor 25-OH-D(3) to inactive compounds. Another enzyme, CYP27B1, involved in the synthesis of 1,25-dihydroxyvitamin D(3) , is stimulated by isoflavonoids, and this may result in a similar effect of increasing in the serum level of 1,25-dihydroxyvitamin D3. CYP27B1 and CYP24 were found in kidneys (the main location of 1,25-(OH) (2)D(3) synthesis) and also in brain cells, osteoclasts, keratinocytes, macrophages, intestine epithelial cells, and in some cancer cells. The expression of VDR was detected not only in the cells primarily targeted by 1,25-dihydroxyvitamin D3, but also in epithelial and mesenchymal cells. Therefore, combined treatment with isoflavonoids and 1,25-dihydroxyvitamin D3 might be effective in both cancer prevention and treatment.

Topics: 25-Hydroxyvitamin D3 1-alpha-Hydroxylase; Animals; Antineoplastic Agents, Hormonal; Antineoplastic Agents, Phytogenic; Cholecalciferol; Colonic Neoplasms; Female; Humans; Isoflavones; Male; Mice; Prostatic Neoplasms; Receptors, Calcitriol; Resveratrol; Steroid Hydroxylases; Stilbenes; Tumor Cells, Cultured; Up-Regulation; Vitamin D3 24-Hydroxylase

Vitamin D deficiency increases risk of prostate cancer. According to our recent results, the key Vitamin D hormone involved in the regulation of cell proliferation in prostate is 25(OH) Vitamin D3. It is mainly acting directly through the Vitamin D receptor (VDR), but partially also through its 1alpha-hydroxylation in the prostate. A deficiency of 25(OH) Vitamin D is common especially during the winter season in the Northern and Southern latitudes due to an insufficient sun exposure, but Vitamin D deficient diet may partially contribute to it. A lack of Vitamin D action may also be due to an altered metabolism or Vitamin D resistance. Vitamin D resistance might be brought up by several mechanisms: Firstly, an increased 24-hydroxylation may increase the inactivation of hormonal Vitamin D metabolites resulting in a Vitamin D resistance. This is obvious in the cancers in which an oncogenic amplification of 24-hydroxykase gene takes place, although an amplification of this gene in prostate cancer has not yet been described. During the aging, the activity of 24-hydroxylase increases, whereas 1alpha-hydroxylation decreases. Furthermore, it is possible that a high serum concentration of 25(OH)D3 could induce 24-hydroxylase expression in prostate. Secondly, Vitamin D receptor gene polymorphism or defects may result in a partial or complete Vitamin D resistance. Thirdly, an overexpression or hyperphosphorylation of retinoblastoma protein may result in an inefficient mitotic control by Vitamin D. Fourthly, endogenous steroids (reviewed by [D.M. Peehl, D. Feldman, Interaction of nuclear receptor ligands with the Vitamin D signaling pathway in prostate cancer, J. Steroid Biochem. Mol. Biol. (2004)]) and phytoestrogens may modulate the expression of Vitamin D metabolizing enzymes. In summary, the local metabolism of hormonal Vitamin D seems to play an important role in the development and progression of prostate cancer.

Topics: 24,25-Dihydroxyvitamin D 3; 25-Hydroxyvitamin D3 1-alpha-Hydroxylase; Calcifediol; Calcitriol; Cell Proliferation; Cholecalciferol; Cytochrome P-450 Enzyme Inhibitors; Cytochrome P-450 Enzyme System; Gene Expression Regulation, Neoplastic; Humans; Male; Phytoestrogens; Prostate; Prostatic Neoplasms; Receptors, Calcitriol; Steroid Hydroxylases; Vitamin D3 24-Hydroxylase

Much interest has developed recently in the use of differentiating agents in the management of solid tumors, specifically prostate cancer. Two classes of drugs that have shown particularly intriguing results are vitamin D(3) and its analogs and the peroxisome proliferator-activated receptor gamma (PPARgamma) ligands. Both the vitamin D(3) receptor and the PPARs are members of the nuclear receptor superfamily of ligand-dependent transcription factors and both are widely expressed by prostate cancer cells. This article reviews in detail the preclinical and clinical data available supporting the use of these agents in the treatment of prostate cancer. The proposed mechanisms of action of these agents and potential future therapeutic roles for these drugs are discussed as well.

Topics: Cell Differentiation; Cholecalciferol; Clinical Trials as Topic; Drug Evaluation, Preclinical; Forecasting; Gene Expression Regulation, Neoplastic; Humans; Ligands; Male; Prostatic Neoplasms; Receptors, Cytoplasmic and Nuclear; Transcription Factors; Transcription, Genetic; Treatment Outcome

Human prostate cells contain receptors for 1alpha,25-dihydroxyvitamin D, the active form of vitamin D. Prostate cancer cells respond to vitamin D(3) with increases in differentiation and apoptosis, and decreases in proliferation, invasiveness and metastasis. These findings strongly support the use of vitamin D-based therapies for prostate cancer and/or as a second-line therapy if androgen deprivation fails. The association between either decreased sun exposure or vitamin D deficiency and the increased risk of prostate cancer at an earlier age, and with a more aggressive progression, indicates that adequate vitamin D nutrition should be a priority for men of all ages. Here we summarize recent advances in epidemiological and biochemical studies of the endocrine and autocrine systems associated with vitamin D and their implications for prostate cancer and in the evaluation of vitamin D(3) and its analogs in preventing and/or treating prostate cancer.

Topics: Cholecalciferol; Comorbidity; Humans; Male; Prostatic Neoplasms; Receptors, Calcitriol; Steroid Hydroxylases; Ultraviolet Rays; United States; Vitamin D; Vitamin D Deficiency

1,25-dihydroxyvitamin D3[1,25(OH)2D3] is a well-known potent regulator of cell growth and differentiation and there is recent evidence of an effect on cell death, tumour invasion and angiogenesis, which makes it a candidate agent for cancer regulation. The classical synthetic pathway of 1,25(OH)2D3 involves 25- and 1 alpha-hydroxylation of vitamin D3, in the liver and kidney, respectively, of absorbed or skin-synthesized vitamin D3. There is recent focus on the importance in growth control of local metabolism of 1,25(OH)2D3, which is a function of local tissue synthetic hydroxylases and particularly the principal catabolizing enzyme, 24-hydroxylase. The classical signalling pathway of 1,25(OH)2D3 employs the vitamin D nuclear receptor (VDR), which is a transcription factor for 1,25(OH)2D3 target genes. Effects of this pathway include inhibition of cellular growth and invasion. Cytoplasmic signalling pathways are increasingly being recognized, which similarly may regulate growth and differentiation but also apoptosis. 1,25(OH)2D3 has a major inhibitory effect on the G1/S checkpoint of the cell cycle by upregulating the cyclin dependent kinase inhibitors p27 and p21, and by inhibiting cyclin D1. Indirect mechanisms include upregulation of transforming growth factor-beta and downregulation of the epidermal growth factor receptor. 1,25(OH)2D3 may induce apoptosis either indirectly through effects on the insulin-like growth receptor and tumour necrosis factor-alpha or more directly via the Bcl-2 family system, the ceramide pathway, the death receptors (e.g. Fas) and the stress-activated protein kinase pathways (Jun N terminal kinase and p38). Inhibition of tumour invasion and metastasis potential has been demonstrated and mechanisms include inhibition of serine proteinases, metalloproteinases and angiogenesis. The lines of evidence for an effect of vitamin D3 in systemic cancer are the laboratory demonstration of relevant effects on cellular growth, differentiation, apoptosis, malignant cell invasion and metastasis; epidemiological findings of an association of the occurrence and outcome of cancers with derangements of vitamin D3/1,25(OH)2D3 and the association of functional polymorphisms of the VDR with the occurrence of certain cancers. In addition, vitamin D3 analogues are being developed as cancer chemotherapy agents. There is accumulating evidence that the vitamin D3/1,25(OH)2D3/VDR axis is similarly important in malignant melanoma (MM). MM cells express

Topics: Breast Neoplasms; Cell Differentiation; Cell Division; Cholecalciferol; Colonic Neoplasms; Female; Humans; Male; Melanoma; Polymorphism, Genetic; Prostatic Neoplasms; Receptors, Calcitriol; Signal Transduction; Skin; Skin Neoplasms; Vitamin D

Topics: Alitretinoin; Androgens; Angiotensin Receptor Antagonists; Animals; Benzimidazoles; Biphenyl Compounds; Cholecalciferol; DNA-Binding Proteins; Drug Design; Genistein; Humans; Male; Neoplasms, Hormone-Dependent; Prostatic Neoplasms; Receptor, Angiotensin, Type 1; Receptors, Angiotensin; Telomerase; Tetrazoles; Tretinoin

Steroid hormones play an important part in prostate biology. Androgens are crucial for the normal development of the prostate gland and in maintaining its functional state in the adult. It seems that the prolonged presence of androgens might also be an important factor in the development of prostate cancer. In addition, androgens and oestrogens appear to play a part in the development of benign prostatic hypertrophy, although the exact nature of their role has not been clearly defined. Stimulation of prostate cancer growth by androgens is well established with androgen withdrawal therapy being the most effective therapy in men with prostate cancer. Additive steroid therapy of metastatic prostate cancer with oestrogens or progestogens has also proved effective. The effects of androgens on prostate cancer cell growth might be mediated through modulation of growth factor expression and alteration of growth factor receptor levels. Androgen response can be modulated by the expression of mutated oncogenes such as ras. Androgen independence can occur through a loss of AR expression or mutation of the AR; however, the patterns of AR expression in normal prostatic tissue from development to adulthood and in cancer are now just beginning to be described. Other steroids, such as the retinoids, show promise as preventive agents, possibly through the modulation of growth factors. Vitamin D compounds modulate prostate cancer cell growth, but their role in prevention and therapy is unclear.

Topics: Androgens; Cholecalciferol; Humans; Male; Prostatic Neoplasms; Receptors, Androgen; Transforming Growth Factor beta

Active surveillance (AS) for patients with prostate cancer (PC) with low risk of PC death is an alternative to radical treatment. A major drawback of AS is the uncertainty whether a patient truly has low risk PC based on biopsy alone. Multiparametric MRI scan together with biopsy, appears useful in separating patients who need curative therapy from those for whom AS may be safe. Two small clinical trials have shown short-term high-dose vitamin D supplementation may prevent PC progression. There is no substantial evidence for its long-term safety and efficacy, hence its use in the care of men with PC on AS needs assessment. This protocol describes the ProsD clinical trial which aims to determine if oral high-dose vitamin D supplementation taken monthly for 2 years can prevent PC progression in cases with low-to-intermediate risk of progression.. This is an Australian national multicentre, 2:1 double-blinded placebo-controlled phase II randomised controlled trial of monthly oral high-dose vitamin D supplementation (50 000 IU cholecalciferol), in men diagnosed with localised PC who have low-to-intermediate risk of disease progression and are being managed by AS. This trial will assess the feasibility, efficacy and safety of supplementing men with an initial oral loading dose of 500 000 IU cholecalciferol, followed by a monthly oral dose of 50 000 IU during the 24 months of AS. The primary trial outcome is the commencement of active therapy for clinical or non-clinical reason, within 2 years of AS.. This trial is approved by Bellberry Ethics Committee (2016-06-459). All results will be reported in peer-reviewed journals.. ACTRN12616001707459.

Topics: Australia; Cholecalciferol; Clinical Trials, Phase II as Topic; Dietary Supplements; Double-Blind Method; Humans; Male; Multicenter Studies as Topic; Prostatic Neoplasms; Randomized Controlled Trials as Topic; Vitamin D; Watchful Waiting

Vitamin D3 might benefit prostate cancer (PCa) patients because prostate cells can locally synthesize the active hormone calcitriol.. Our objective was to determine the effects of oral vitamin D3 on vitamin D metabolites and PCa proliferative activity in prostate tissue.. We conducted a double-blind randomized clinical trial at surgical oncology clinics in Toronto, Canada.. PCa patients (Gleason 6 or 7) participated in the study. Of 66 subjects who were enrolled, 63 completed the dosing protocol.. Vitamin D3 (400, 10 000, or 40 000 IU/d) was orally administered before radical prostatectomy.. We evaluated vitamin D metabolite levels and Ki67 labeling in surgical prostate tissue. Safety measures, PTH, and prostate-specific antigen (PSA) were also assessed.. Prostate tissue and serum levels of vitamin D metabolites, including calcitriol, increased dose dependently (P < .03) and were significantly higher in the 40 000-IU/d group than in every other dose group (P < .03). Prostate vitamin D metabolites correlated positively with serum levels (P < .0001). Ki67 measures did not differ significantly among vitamin D dose groups. However, cross-sectional analysis indicated that the calcitriol level attained in prostate was inversely associated with Ki67 intensity and Ki67 (3+) percent positive nuclei in PCa and benign tissue (P < .05). Safety measures did not change adversely with dosing. Compared with the 400-IU/d group, serum PTH and PSA were lower in the combined higher-dose groups at the end of the study (P < .02).. Oral vitamin D3 raised prostate calcitriol levels (level 1 evidence) and modestly lowered both PSA and PTH. Although Ki67 expression did not differ among dose groups, its levels correlated inversely with prostate calcitriol. These suggestions of clinical benefit justify continued clinical research.

Topics: Aged; Carcinoma; Cholecalciferol; Dose-Response Relationship, Drug; Double-Blind Method; Humans; Ki-67 Antigen; Male; Middle Aged; Prostatic Neoplasms; Staining and Labeling; Tissue Array Analysis; Validation Studies as Topic; Vitamin D

Prostate cancer (CaP) is one of the most common cancers in men. On the basis of international and Polish epidemiological data it is estimated that is the second leading cause of death from cancer. These data tend to look for underlying causes such a high incidence. Detected in 1990, the relationship between UV radiation and the reduction of mortality rate due to CaP gave rise to the search for effects of vitamin D, in CaP. The aim of this study was to evalu ate the concentration of 25(OH)D3 in patients treated for prostate cancer (CaP) compared to the control group of healthy men, and attempt to assess the relationship 25(OH)D3 shortage of CaP incidence and degree of its clinical advancement.. The study included 42 men, aged from 42 to 86 years (average age 66.14+/-8.92 years) treated between 2005-2013 in śCO due to prostate cancer. The control group consisted of 40 healthy men aged from 42 to 78 years (average age 63.17+/-9.02) in whom CaP and other cancer disease were excluded. Patients treated for CaP were divid ed into two groups depending on the severity of the cancer being evaluated by the TNM scale. Group 1 consisted of 11 patients with low severity of CaP-T1, group 2 -31 patients with higher tumor stage (T2+T3+T4). In all patients, serum 25(OH)D3 was marked in venous blood collected in the morning.. The concentration of 25(OH)D3 in the group of patients with CaP occured in 80.94. There was no statistically significant difference between patients 25(OH)D3 concentra tions of CaP and control group (p = 0.3756). In both subgroups of patients with CaP showed no statistically significant difference 25(OH)D3 concentra tions (p = 0.5672), depending on the tumor advancement stage (according to TNM).. The majority of tested patients with prostate cancer were low concentrations of vitamin D3. There were no significant differences in concentrations of vitamin D3 in the group of patients with CaP and in the control group. Based on the analysis no relationship between the 25(OH)D3 concentration and the stage of CaP was showed, too.

Topics: Adult; Aged; Aged, 80 and over; Biomarkers, Tumor; Cholecalciferol; Humans; Male; Middle Aged; Neoplasm Staging; Prostatic Neoplasms; Reference Values

We wanted to investigate vitamin D in low-risk prostate cancer.. The objective of the study was to determine whether vitamin D(3) supplementation at 4000 IU/d for 1 yr is safe and would result in a decrease in serum levels of prostate-specific antigen (PSA) or in the rate of progression.. In this open-label clinical trial (Investigational New Drug 77,839), subjects were followed up until repeat biopsy.. All subjects were enrolled through the Medical University of South Carolina and the Ralph H. Johnson Veterans Affairs Medical Center, both in Charleston, SC.. All subjects had a diagnosis of low-risk prostate cancer. Fifty-two subjects were enrolled in the study, 48 completed 1 yr of supplementation, and 44 could be analyzed for both safety and efficacy objectives.. The intervention included vitamin D(3) soft gels (4000 IU).. Adverse events were monitored throughout the study. PSA serum levels were measured at entry and every 2 months for 1 yr. Biopsy procedures were performed before enrollment (for eligibility) and after 1 yr of supplementation.. No adverse events associated with vitamin D(3) supplementation were observed. No significant changes in PSA levels were observed. However, 24 of 44 subjects (55%) showed a decrease in the number of positive cores or decrease in Gleason score; five subjects (11%) showed no change; 15 subjects (34%) showed an increase in the number of positive cores or Gleason score.. Patients with low-risk prostate cancer under active surveillance may benefit from vitamin D(3) supplementation at 4000 IU/d.

Topics: Aged; Biopsy, Fine-Needle; Carcinoma; Cholecalciferol; Dietary Supplements; Dose-Response Relationship, Drug; Down-Regulation; Humans; International System of Units; Male; Middle Aged; Population Surveillance; Prostate; Prostatic Neoplasms; Risk Factors; Time Factors; Treatment Outcome; Watchful Waiting

Today, androgen deprivation therapy is a cornerstone of treatment for advanced prostate cancer, although it presents important complications such as osteoporosis. Neridronate, a relatively new bisphosphonate, is able to prevent bone loss in patients with prostate cancer during androgen ablation.. Androgen-deprivation therapy (ADT) is a cornerstone of treatment for advanced prostate cancer. This therapy has iatrogenic complications, such as osteoporosis. The aim of our study was to evaluate the efficacy of neridronate, a relatively new bisphosphonate, to prevent bone loss during androgen ablation.. Forty-eight osteoporotic patients with prostate cancer, treated with 3-month depot triptorelina, were enrolled and randomly assigned to two different treatment groups: group A (n = 24) was treated with a daily calcium and cholecalciferol supplement (500 mg of elemental calcium and 400 IU cholecalciferol), and group B (n = 24) received in addition to the same daily calcium and cholecalciferol supplement, 25 mg of neridronate given intramuscularly every month. All patients also received bicalutamide for 4 weeks. Lumbar and femoral BMD was evaluated by DXA at baseline and after 1 year of therapy; moreover, deoxypyridinoline (DPD) and bone alkaline phosphatase (BALP) were determined at the beginning, midway through, and at the end of the study.. After 6 and 12 months, whereas patients treated only with calcium and cholecalciferol (group A) showed a marked bone loss, with increased levels of DPD and BALP compared with baseline values, patients treated also with neridronate (group B) had substantially unchanged levels of these markers. After 1 year of treatment, lumbar and total hip BMD decreased significantly in patients treated only with calcium and cholecalciferol (group A), whereas it did not change significantly at any skeletal site in patients treated also with neridronate (group B). No relevant side effects were recorded during our study.. Neridronate is an effective treatment in preventing bone loss in the hip and lumbar spine in men receiving ADT for prostate cancer.

Topics: Absorptiometry, Photon; Aged; Alkaline Phosphatase; Amino Acids; Androgen Antagonists; Androgens; Antineoplastic Agents, Hormonal; Bone and Bones; Bone Density; Calcium; Cholecalciferol; Diphosphonates; Humans; Male; Osteoporosis; Prostatic Neoplasms; Time Factors; Triptorelin Pamoate

To investigate the influence of targeted serum vitamin-D level and omega-6:3 fatty-acid ratio on prostate-specific antigen (PSA) level in men with prostate cancer managed with active surveillance by providing a nutritional intervention and vitamin supplementation.. Sixty-eight patients with biopsy-proven National Comprehensive Cancer Network very-low or low-risk prostate cancer were enrolled in the prostate cancer nutrition and genetics clinic at the Cleveland Clinic from July 2013-December 2019. Patients adhered to a specific dietary regimen devoid of animal-based products and foods containing omega-6 polyunsaturated fatty acids (PUFAs). The supplement regimen consisted of: Omega-3 PUFAs 720mg (3/day); curcumin 2000 mg/day; vitamin D3 dose titrated to achieve serum level of 60 ng/ml; and vitamin B-complex 1000 mg (4 times weekly). Patients underwent periodic monitoring of PSA, serum vitamin D, and PUFA levels and had frequent follow-up with the nutritionist which included a food frequency questionnaire. Interval prostate biopsy was performed as clinically indicated and/or at 9 months.. The mean and 95% confidence interval of PSA slope and Vitamin D serum levels slope were 0.11 (0-0.25) ng/mL/month and 4.65 (3.09-5.98) ng/mL/month, respectively. Patients with higher initial vitamin D levels were twice as likely to have a downward PSA trend (OR = 2.04, 95% confidence interval 1.04-4.01, P = .04). Fifty-five patients underwent follow-up biopsy, all showing no progression of disease. Three patients had loose bowel movements that required omega-3 and or curcumin dose adjustments.. Intensive nutritional intervention with Vitamin D and Omega-3 PUFA supplementation may benefit men on active surveillance for prostate cancer and further studies are warranted.

Topics: Aged; Cholecalciferol; Dietary Supplements; Fatty Acids, Omega-3; Humans; Male; Middle Aged; Prostate-Specific Antigen; Prostatic Neoplasms; Vitamins; Watchful Waiting

Topics: Calcium; Cholecalciferol; Humans; Male; Prostatic Neoplasms; Receptors, Calcium-Sensing; TRPC6 Cation Channel; Up-Regulation

Vitamin D

Topics: Cholecalciferol; Dietary Supplements; Erythrocytes; Free Radical Scavengers; Homeostasis; Humans; Male; Metals; Middle Aged; Neoplasm Grading; Oxidation-Reduction; Prostate-Specific Antigen; Prostatic Neoplasms

Active surveillance has emerged as an alternative to immediate treatment for men with low-risk prostate cancer. Accordingly, identification of environmental factors that facilitate progression to more aggressive stages is critical for disease prevention. Although calcium-enriched diets have been speculated to increase prostate cancer risk, their impact on early-stage tumors remains unexplored. In this study, we addressed this issue with a large interventional animal study. Mouse models of fully penetrant and slowly evolving prostate tumorigenesis showed that a high calcium diet dramatically accelerated the progression of prostate intraepithelial neoplasia, by promoting cell proliferation, micro-invasion, tissue inflammation, and expression of acknowledged prostate cancer markers. Strikingly, dietary vitamin D prevented these calcium-triggered tumorigenic effects. Expression profiling and in vitro mechanistic studies showed that stimulation of PC-3 cells with extracellular Ca

Topics: Animals; Calcium; Cell Line, Tumor; Cholecalciferol; Diet; Dietary Supplements; Disease Models, Animal; Humans; Male; Mice; Mice, Inbred C57BL; Prostatic Neoplasms; Receptors, Calcium-Sensing; TRPC Cation Channels; TRPC6 Cation Channel; Up-Regulation

Topics: Calcium; Cholecalciferol; Humans; Male; Prostatic Neoplasms; Receptors, Calcium-Sensing; TRPC6 Cation Channel; Up-Regulation; Vitamin D

Cryoablation, an effective means of ablating cancer, is often used in conjunction with adjuvants that target cancer cells in a specific cell cycle stage to increase treatment efficacy. The objective of this study was to investigate the impact of cell cycle stage on cancer freeze response as well as investigate the potential cellular kinetic effect of calcitriol, the active metabolic of vitamin D3, when used as a cryosensitizing adjuvant in order to maximize prostate cancer cell death.. Cell cycle distribution of PC-3 cells was analyzed via flow cytometry to compare gap 1, synthesis, and gap 2/mitosis phase subpopulations pre- and postfreeze as well as changes elicited by calcitriol pretreatment. Distinct gap 1, synthesis, and gap 2/mitosis phase populations were obtained through fluorescence-activated cell sorting and synthesis phase thymidine synchronization. Posttreatment viability was assessed using alamarBlue and fluorescence microscopy to assess live, apoptotic, and necrotic subpopulations.. A small but statistically significant increase in synthesis phase and decrease in gap 2/mitosis phase populations was noted at 6 hours postfreeze in asynchronous samples. Synchronization in synthesis phase yielded an increase in cell death when combined with freezing to both -15°C and -20°C. Calcitriol pretreatment increased the gap 1 phase population by 20% and a synergistic decrease in viability following freezing. However, gap 1-sorted populations combined with calcitriol treatment did not exhibit this synergistic effect. Fluorescence microscopy of fluorescence-activated cell sorting-sorted cells revealed necrosis as the predominant form of cell death in all phases, though apoptosis did play a role.. Although initial results suggested a potential sensitivity, PC-3 cells exposed to freezing as sorted populations did not reveal significant differences in cell death. As such, the data from this study suggest that there is no difference in cell cycle stage sensitivity to freezing injury.

Topics: Androgens; Apoptosis; Cell Cycle; Cell Line, Tumor; Cell Survival; Cholecalciferol; Cryosurgery; Freezing; Humans; Male; Prostatic Neoplasms; Time Factors

African-Americans (AA) have increased prostate cancer risk and a greater mortality rate than European-Americans (EA). AA exhibit a high prevalence of vitamin D deficiency. We examined the global prostate transcriptome in AA and EA, and the effect of vitamin D. Twenty-seven male subjects (ten AA and 17 EA), slated to undergo prostatectomy were enrolled in the study. Fourteen subjects received vitamin D. AA show higher expression of genes associated with immune response and inflammation.. Systems level analyses support the concept that Inflammatory processes may contribute to disease progression in AA. These transcripts can be modulated by a short course of vitamin D

Topics: Aged; Black or African American; Cholecalciferol; Cohort Studies; Dietary Supplements; Humans; Male; Middle Aged; Prospective Studies; Prostate; Prostatectomy; Prostatic Neoplasms; Systems Analysis; Transcriptome; White People

Metformin and vitamin D₃ both exhibit a strong antiproliferative action in numerous cancer cell lines, including in human prostate cancer cells. Here we showed that the combination of the two drugs had a much stronger effect on DU145 human prostate cancer cell growth than either drug alone. In this research, cell proliferation was measured by methylthiazol tetrazolium (MTT) assay. Cell apoptosis was determined with Hoechst 33342 staining. Western blotting and cell cycle analyses were used to elucidate potential mechanisms of interaction between the drugs. It is shown that in cultured DU145 cells, vitamin D₃ combined with metformin exhibits synergistic effects on cell proliferation and apoptosis. The underlying antitumor mechanisms may involve altered cycle distribution with a G1/S cell cycle arrest, activation of phospho-AMPK with subsequent inhibition of downstream mTOR signalling pathway, down-regulate c-Myc expression, and reducing the level of anti-apoptotic protein p-Bcl-2. In conclusion, metformin and vitamin D₃ synergistically inhibit DU145 cell growth, indicating a promising clinical therapeutic strategy for the treatment of androgen-independent prostate cancer.

Topics: AMP-Activated Protein Kinases; Cell Cycle; Cell Line, Tumor; Cholecalciferol; Dose-Response Relationship, Drug; Drug Synergism; Growth Inhibitors; Humans; Male; Metformin; Prostatic Neoplasms; Signal Transduction; TOR Serine-Threonine Kinases

A major limitation of exogenous vitamin D3 administration for the treatment of prostate cancer is the marginal, if any, clinical efficacy. We dissected the basis for the resistance to the vitamin D3 antitumor properties and specifically examined the effect of its major catabolic enzyme, CYP24A1, in prostate cancer. Local CYP24A1 expression levels and the effect of selective modulation were analyzed using tissue microarrays from needle core biopsy specimens and xenograft-bearing mouse models. CYP24A1 mRNA was elevated in malignant human prostate tissues compared to benign lesions. High CYP24A1 protein levels were seen in poorly differentiated and highly advanced stages of prostate cancer and correlated with parallel increase in the tumor proliferation rate. The use of CYP24A1 RNAi enhanced the cytostatic effects of vitamin D3 in human prostate cancer cells. Remarkably, subcutaneous and orthotopic xenografts of prostate cancer cells harboring CYP24A1 shRNA resulted in a drastic reduction in tumor volume when mice were subjected to vitamin D3 supplementation. CYP24A1 may be a predictive marker of vitamin D3 clinical efficacy in patients with advanced prostate cancer. For those with up-regulated CYP24A1, combination therapy with RNAi targeting CYP24A1 could be considered to improve clinical responsiveness to vitamin D3.

Topics: Animals; Cell Line, Tumor; Cell Proliferation; Cholecalciferol; Humans; Immunohistochemistry; In Vitro Techniques; Magnetic Resonance Imaging; Male; Mice; Mice, SCID; Prostatic Neoplasms; Reverse Transcriptase Polymerase Chain Reaction; RNA, Small Interfering; Steroid Hydroxylases; Vitamin D3 24-Hydroxylase; Xenograft Model Antitumor Assays

Vitamin D3 might benefit prostate cancer (PCa) patients because prostate cells can locally synthesize the active hormone calcitriol.. Our objective was to determine the effects of oral vitamin D3 on vitamin D metabolites and PCa proliferative activity in prostate tissue.. We conducted a double-blind randomized clinical trial at surgical oncology clinics in Toronto, Canada.. PCa patients (Gleason 6 or 7) participated in the study. Of 66 subjects who were enrolled, 63 completed the dosing protocol.. Vitamin D3 (400, 10000, or 40000 IU/d) was orally administered before radical prostatectomy.. We evaluated vitamin D metabolite levels and Ki67 labeling in surgical prostate tissue. Safety measures, PTH, and prostate-specific antigen (PSA) were also assessed.. Prostate tissue and serum levels of vitamin D metabolites, including calcitriol, increased dose dependently (P<.03) and were significantly higher in the 40000-IU/d group than in every other dose group (P<.03). Prostate vitamin D metabolites correlated positively with serum levels (P<.0001). Ki67 measures did not differ significantly among vitamin D dose groups. However, cross-sectional analysis indicated that the calcitriol level attained in prostate was inversely associated with Ki67 intensity and Ki67 (3+) percent positive nuclei in PCa and benign tissue (P<.05). Safety measures did not change adversely with dosing. Compared with the 400-IU/d group, serum PTH and PSA were lower in the combined higher-dose groups at the end of the study (P< .02).. Oral vitamin D3 raised prostate calcitriol levels (level 1 evidence) and modestly lowered both PSA and PTH. Although Ki67 expression did not differ among dose groups, its levels correlated inversely with prostate calcitriol. These suggestions of clinical benefit justify continued clinical research.

Topics: Carcinoma; Cholecalciferol; Humans; Ki-67 Antigen; Male; Prostatic Neoplasms; Vitamin D

The potency of 25-hydroxyvitamin D3 (25(OH)D3) is increased by several fold through its metabolism into 1α,25-dihydroxyvitamin D3 (1α,25(OH)2D3) by cytochrome P450 27B1 (CYP27B1). Thus, the pivotal role of 1α-hydroxylation in the activation of vitamin D compounds is well known. Here, we examined the metabolism of 25-hydroxy-16-ene-23-yne-vitamin D3 (25(OH)-16-ene-23-yne-D3), a synthetic analog of 25(OH)D3 in a cell-free system and demonstrated that 25(OH)-16-ene-23-yne-D3 is neither activated by CYP27B1 nor inactivated by cytochrome P450 24A1 (CYP24A1). These findings were also confirmed in immortalized normal human prostate epithelial cells (PZ-HPV-7) which are known to express both CYP27B1 and CYP24A1, indicating that the structural modifications featured in 25(OH)-16-ene-23-yne-D3 enable the analog to resist the actions of both CYP27B1 and CYP24A1. To provide intelligible structure-function information, we also performed molecular docking analysis between the analog and CYP27B1. Furthermore, 25(OH)-16-ene-23-yne-D3 was found to suppress the growth of PZ-HPV-7 cells with a potency equivalent to 1α,25(OH)2D3. The antiproliferative activity of 25(OH)-16-ene-23-yne-D3 was found to be vitamin D receptor (VDR)-dependent as it failed to inhibit the growth of mammary tumor cells derived from VDR-knockout mice. Furthermore, stable introduction of VDR into VDR-knockout cells restored the growth inhibition by 25(OH)-16-ene-23-yne-D3. Thus, we identified 25-hydroxy-16-ene-23-yne-vitamin D3 as a novel non-1α-hydroxylated vitamin D analog which is equipotent to 1α,25(OH)2D3 in its antiproliferative activity. We now propose that the low potency of the intrinsic VDR-mediated activities of 25(OH)D3 can be augmented to the level of 1α,25(OH)2D3 without its activation through 1α-hydroxylation by CYP27B1, but by simply preventing its inactivation by CYP24A1.

Topics: 25-Hydroxyvitamin D3 1-alpha-Hydroxylase; Animals; Catalysis; Cell Line, Tumor; Cell Proliferation; Cholecalciferol; Drug Resistance, Neoplasm; Humans; Male; Mice; Molecular Docking Simulation; Prostatic Neoplasms; Receptors, Calcitriol; Vitamin D3 24-Hydroxylase

Patients with prostate cancer treated with androgen deprivation therapy (ADT) eventually develop castrate-resistant prostate cancer (CRPC). 1,25-Dihydroxyvitamin D3 (1,25D3/calcitriol) is a potential adjuvant therapy that confers antiproliferative and pro-differentiation effects in vitro, but has had mixed results in clinical trials. The impact of the tumor microenvironment on 1,25D3 therapy in patients with CRPC has not been assessed. Transforming growth factor β (TGFβ), which is associated with the development of tumorigenic "reactive stroma" in prostate cancer, induced vitamin D3 receptor (VDR) expression in the human WPMY-1 prostate stromal cell line. Similarly, TGFβ enhanced 1,25D3-induced upregulation of CYP24A1, which metabolizes 1,25D3 and thereby limits VDR activity. Ablation of Hic-5, a TGFβ-inducible nuclear receptor coregulator, inhibited basal VDR expression, 1,25D3-induced CYP24A1 expression and metabolism of 1,25D3 and TGFβ-enhanced CYP24A1 expression. A Hic-5-responsive sequence was identified upstream (392-451 bp) of the CYP24A1 transcription start site that is occupied by VDR only in the presence of Hic-5. Ectopic expression of Hic-5 sensitized LNCaP prostate tumor cells to growth-inhibitory effects of 1,25D3 independent of CYP24A1. The sensitivity of Hic-5-expressing LNCaP cells to 1,25D3-induced growth inhibition was accentuated in coculture with Hic-5-ablated WPMY-1 cells. Therefore, these findings indicate that the search for mechanisms to sensitize prostate cancer cells to the antiproliferative effects of VDR ligands needs to account for the impact of VDR activity in the tumor microenvironment.. Hic-5 acts as a coregulator with distinct effects on VDR transactivation, in prostate cancer and stromal cells, and may exert diverse effects on adjuvant therapy designed to exploit VDR activity in prostate cancer.

Topics: Androgens; Cell Line, Tumor; Cholecalciferol; DNA-Binding Proteins; Humans; Male; Prostatic Neoplasms; Receptors, Calcitriol; Receptors, Transforming Growth Factor beta; Stromal Cells; Transcription Initiation Site; Transcription, Genetic; Transcriptional Activation; Transforming Growth Factor beta; Up-Regulation; Vitamin D3 24-Hydroxylase

1α-25(OH)2 vitamin D3 (1-25D), an active hormonal form of Vitamin D3, is a well-known chemopreventive and pro-differentiating agent. It has been shown to inhibit the growth of several prostate cancer cell lines. Gap junctions, formed of proteins called connexins (Cx), are ensembles of cell-cell channels, which permit the exchange of small growth regulatory molecules between adjoining cells. Cell-cell communication mediated by gap junctional channels is an important homeostatic control mechanism for regulating cell growth and differentiation. We have investigated the effect of 1-25D on the formation and degradation of gap junctions in an androgen-responsive prostate cancer cell line, LNCaP, which expresses retrovirally-introduced Cx32. Connexin32 is expressed by the luminal and well-differentiated cells of normal prostate and prostate tumors. Our results document that 1-25D enhances the expression of Cx32 and its subsequent assembly into gap junctions. Our results further show that 1-25D prevents androgen-regulated degradation of Cx32, post-translationally, independent of androgen receptor (AR)-mediated signaling. Finally, our findings document that formation of gap junctions sensitizes Cx32-expressing LNCaP cells to the growth inhibitory effects of 1-25D and alters their morphology. These findings suggest that the growth-inhibitory effects of 1-25D in LNCaP cells may be related to its ability to modulate the assembly of Cx32 into gap junctions.

Topics: Androgens; Animals; Blotting, Western; Cell Line, Tumor; Cholecalciferol; Connexins; Gap Junction beta-1 Protein; Gap Junctions; Humans; Male; Prostatic Neoplasms; Receptors, Androgen; Retinoids

19-nor-14-epi-23-yne-1,25(OH)(2) D(3) (inecalcitol) is a unique vitamin D(3) analog. We evaluated the activity of inecalcitol in a human prostate cancer model system. The analog was 11-fold more potent than 1,25(OH)(2) D(3) in causing 50% clonal growth inhibition of androgen-sensitive human prostate cancer LNCaP cells. Inecalcitol, more than 1,25(OH)(2) D(3) , reduced in a dose-dependent manner the expression levels of the transcription factor ETS variant 1 and the serine/threonine protein kinase Pim-1, both of which are upregulated in prostate cancer. Remarkably, dose challenge experiments revealed that inecalcitol maximal tolerated dose (MTD) by intraperitoneal (i.p.) administration was 30 μg/mouse (1,300 μg/kg) three times per week, while we previously found that the MTD of 1,25(OH)(2) D(3) is 0.0625 μg/mouse; therefore, inecalcitol is 480 times less hypercalcemic than 1,25(OH)(2) D(3) . Pharmacokinetic studies showed that plasma half-life of inecalcitol were 18.3 min in mice. A xenograft model of LNCaP cells was developed in immunodeficient mice treated with inecalcitol. The tumors of the diluent-treated control mice increased in size but those in the inecalcitol treatment group did not grow. Our data suggest that inecalcitol inhibits androgen-responsive prostate cancer growth in vivo and should be examined either alone or with other chemotherapy in clinical trials in individuals with rising serum prostate-specific antigen after receiving either surgery or irradiation therapy with curative intent.

Topics: Alkynes; Androgens; Animals; Cell Line, Tumor; Cholecalciferol; Humans; Male; Mice; Neoplasms, Hormone-Dependent; Prostatic Neoplasms; Tumor Cells, Cultured; Xenograft Model Antitumor Assays

To investigate the effect and molecular mechanisms of action of Vitamin D(3) (VD(3) ) as a neo-adjunctive agent before cryosurgery in an effort to increase treatment efficacy for prostate cancer (CaP). To eliminate the potential for disease recurrence that exists at the periphery of the freeze lesion, where temperatures may be insufficient to destroy both androgen-sensitive (AS) and androgen-insensitive (AI) CaP.. Human CaP cells, LNCaP, were each genetically altered to express the AS and AI phenotypes and subjected to VD(3) treatment and freezing in an in vitro and tissue-engineered model. Cell viability, caspase inhibitor and western blot studies were used to determine the basis of the different responses of AI and AS cells to VD(3) cryosensitization.. VD(3) was found to be a highly effective cryosensitizer, resulting in a >50% overall increase in cell death after -15 °C freezing. Fluorescence microscopy, western blot analysis and caspase protease assays confirmed that the increased activation of apoptosis was modulated through a mitochondrial-mediated pathway. Caspase inhibition studies showed that apoptosis played an integral role in cell death, with VD(3) cryosensitivation-induced apoptotic events responsible for >30% of the overall cell death after -15 °C freezing.. The present study suggests that the use of VD(3) as a cryosensitizer increases cryoablation efficacy through the increased activity of apoptosis as well as through necrosis. The data show that through VD(3) treatment the overall level of AI CaP cell tolerance to freezing is reduced to a level similar to that of AS CaP. VD(3) pre-treatment in conjunction with cryoablation may increase treatment efficacy and reduce disease recurrence for CaP patients.

Topics: Apoptosis; Biological Assay; Blotting, Western; Caspases; Cell Death; Cholecalciferol; Cryosurgery; Humans; Male; Microscopy, Fluorescence; Mitochondria; Prostatic Neoplasms; Treatment Outcome; Tumor Cells, Cultured; Vitamins

1,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3) or calcitriol], the hormonally active vitamin D metabolite, exhibits anticancer actions in models of breast cancer and prostate cancer. Because CYP27B1 (1α-hydroxylase), the enzyme catalyzing 1,25(OH)(2)D(3) formation in the kidney, is also expressed in extrarenal tissues, we hypothesize that dietary vitamin D(3) will be converted to 25(OH)D(3) in the body and then to 1,25(OH)(2)D(3) locally in the cancer microenvironment in which it will exert autocrine/paracrine anticancer actions. Immunocompromised mice bearing MCF-7 breast cancer xenografts showed significant tumor shrinkage (>50%) after ingestion of a vitamin D(3)-supplemented diet (5000 IU/kg) compared with a control diet (1000 IU/kg). Dietary vitamin D(3) inhibition of tumor growth was equivalent to administered calcitriol (0.025, 0.05, or 0.1 μg/mouse, three times a week). Both treatments equivalently inhibited PC-3 prostate cancer xenograft growth but to a lesser extent than the MCF-7 tumors. Calcitriol at 0.05 μg and 0.1 μg caused modest but statistically significant increases in serum calcium levels indicating that the dietary vitamin D(3) comparison was to a maximally safe calcitriol dose. Dietary vitamin D(3) did not increase serum calcium, demonstrating its safety at the concentration tested. The vitamin D(3) diet raised circulating 1,25 dihydroxyvitamin D levels and did not alter CYP27B1 mRNA in the kidney but increased it in the tumors, suggesting that extrarenal sources including the tumors contributed to the elevated circulating 1,25 dihydroxyvitamin D(3). Both calcitriol and dietary vitamin D(3) were equipotent in suppressing estrogen synthesis and signaling and other proinflammatory and growth signaling pathways. These preclinical data demonstrate the potential utility of dietary vitamin D(3) supplementation in cancer prevention and therapy.

Topics: 25-Hydroxyvitamin D3 1-alpha-Hydroxylase; Animals; Body Weight; Breast Neoplasms; Calcitriol; Calcium; Cell Line, Tumor; Cholecalciferol; Dietary Supplements; Estrogen Receptor alpha; Female; Gene Expression Regulation, Neoplastic; Humans; Immunohistochemistry; Male; Mice; Mice, Nude; Ovariectomy; Prostatic Neoplasms; Receptors, Calcitriol; Reverse Transcriptase Polymerase Chain Reaction; Steroid Hydroxylases; Tumor Burden; Vitamin D3 24-Hydroxylase; Vitamins; Xenograft Model Antitumor Assays

Calcitriol has been reported to have antitumor efficacy in several cancers. In this study, we hypothesized that calcitriol may potentially function as a cryosensitizer that can enhance cryoablation, and we investigated several molecular marker changes in a murine model of prostate cancer.. Murine prostate tumors (RM-9) were grown in male C57BL/6J mice subcutaneously with neoadjuvant intratumoral injection of calcitriol followed by cryoablation. The microenvironmental changes after cryoablation alone and in combination with calcitriol were analyzed in a comparative fashion using immunohistochemistry and Western blot analyses.. Both cryoablation and the combination group could suppress tumor growth after treatment compared with the control. At final pathologic assessment, a larger necrotic area was seen in the combination group (P = .026). Although microvessel density (CD31) and the area of hypoxia (pimonidazole) was not different between the control and combination groups, cell proliferation (Ki-67) significantly decreased in the combination treatment (P = .035). In Western blot analyses, several markers for apoptosis were expressed significantly higher with the combination treatment.. The synergistic effect of calcitriol with cryoablation was demonstrated because of enhanced antitumor efficacy by increasing necrosis and apoptosis and reduced cell proliferation. This study suggests that calcitriol is a potentially applicable reagent as a freeze sensitizer to cryoablation.

Topics: Animals; Cholecalciferol; Cryosurgery; Disease Models, Animal; Male; Mice; Mice, Inbred C57BL; Preoperative Care; Prostatic Neoplasms; Vitamins

Serum 25-hydroxyvitamin D [25(OH)D] is the major circulating form of vitamin D and a standard indicator of vitamin D status. Emerging evidence in the literature suggests a high prevalence of suboptimal vitamin D (as defined by serum 25(OH)D levels of <32 ng/ml) as well as an association between lower serum levels and higher mortality in cancer. We investigated the effect of oral vitamin D supplementation as a means for restoring suboptimal levels to optimal levels in cancer.. This is a retrospective observational study of 2198 cancer patients who had a baseline test prior to initiation of cancer therapy at our hospital to evaluate serum 25(OH)D levels between Jan 08 and Dec 09 as part of their initial nutritional evaluation. Patients with baseline levels of < = 32 ng/ml (n = 1651) were considered to have suboptimal serum 25(OH)D levels and were supplemented with 8000 IU of Vitamin D3 (four 2000 IU D3 capsules) daily as part of their nutritional care plan. The patients were retested at their first follow-up visit. Of 1651 patients, 799 were available for follow up assessment. The mean serum 25(OH)D levels were compared in these 799 patients across the 2 time points (baseline and first follow-up) using paired sample t-test. We also investigated the factors associated with response to vitamin D supplementation.. Of 2198 patients, 814 were males and 1384 females. 1051 were newly diagnosed and treated at our hospital while 1147 were diagnosed and treated elsewhere. The mean age at presentation was 55.4 years. The most common cancer types were breast (500, 22.7%), lung (328, 14.9%), pancreas (214, 9.7%), colorectal (204, 9.3%) and prostate (185, 8.4%). The mean time duration between baseline and first follow-up assessment was 14.7 weeks (median 10.9 weeks and range 4 weeks to 97.1 weeks). The mean serum 25(OH)D levels were 19.1 ng/ml (SD = 7.5) and 36.2 ng/ml (SD = 17.1) at baseline and first follow-up respectively; p < 0.001. Patients with prostate and lung cancer had the highest percentage of responders (70% and 69.2% respectively) while those with colorectal and pancreas had the lowest (46.7% each). Similarly, patients with serum levels 20-32 ng/ml at baseline were most likely to attain levels > 32 ng/ml compared to patients with baseline levels < 20 ng/ml.. The response to supplementation from suboptimal to optimal levels was greatest in patients with prostate and lung cancer as well as those with baseline levels between 20-32 ng/ml. Characteristics of non-responders as well as those who take longer to respond to supplementation need to be further studied and defined. Additionally, the impact of improved serum 25(OH)D levels on patient survival and quality of life needs to be investigated.

Topics: Antineoplastic Combined Chemotherapy Protocols; Cholecalciferol; Colorectal Neoplasms; Female; Humans; Lung Neoplasms; Male; Middle Aged; Neoplasms; Pancreatic Neoplasms; Prostatic Neoplasms; Retrospective Studies; Vitamin D; Vitamin D Deficiency

The oxidizing anticancer system of vitamin C and vitamin K₃ (VC:VK₃, producing hydrogen peroxide via superoxide) was combined individually with melatonin, curcumin, quercetin, or cholecalciferol (VD₃) to determine interactions. Substrates were LNCaP and PC-3 prostate cancer cell lines. Three of the tested antioxidants displayed differences in cell line cytotoxicity. Melatonin combined with VC:VK₃ quenched the oxidizing effect, while VC:VK₃ applied 24 hours after melatonin showed no quenching. With increasing curcumin concentrations, an apparent combined effect of VC:VK₃ and curcumin occurred in LNCaP cells, but not PC-3 cells. Quercetin alone was cytotoxic on both cell lines, but demonstrated an additional 50-percent cytotoxicity on PC-3 cells when combined with VC:VK₃. VD₃ was effective against both cell lines, with more effect on PC-3. This effect was negated on LNCaP cells with the addition of VC:VK₃. In conclusion, a natural antioxidant can enhance or decrease the cytotoxicity of an oxidizing anticancer system in vitro, but generalizations about antioxidants cannot be made.

Topics: Antineoplastic Agents; Antioxidants; Ascorbic Acid; Cell Cycle; Cholecalciferol; Curcumin; Cytotoxins; Drug Interactions; Drug Therapy, Combination; Humans; Male; Melatonin; Oxidative Stress; Prostatic Neoplasms; Quercetin; Tumor Cells, Cultured; Vitamin K 3

The high incidence of prostate cancer and lack of an effective, long-term treatment for metastatic disease highlights the need for more potent non-calcemic vitamin D analogs as potential alternative or combinational prostate cancer therapies. Among the analogs, 19-nor-1alpha,25-dihydroxyvitamin D2 (19-nor-1alpha,25(OH)2D2) known as paricalcitol or Zempler, has less calcemic effects and an equipotential activity as 1alpha,25-dihydroxyvitamin D3 (1alpha,25(OH)2D3) in several in vivo and in vitro systems. It was recently demonstrated that a modified analog of paricalcitol, 19-nor-2alpha-(3-hydroxypropyl)-1alpha,25-dihydroxyvitamin D3 (MART-10) compared to 1alpha,25(OH)2D3 was more effective in inhibiting proliferation of an immortalized normal prostate cell line (PZ-HPV-7) (1,000-fold) and invasion of PC-3 prostate cancer cells (10-fold). In this study, the effects of MART-10 and 1alpha,25(OH)2D3 on proliferation, vitamin D receptor transactivation, vitamin D-binding protein (DBP) binding, CYP24A1 (24-OHase) substrate hydroxylation kinetics, and induction of CYP24A1 gene expression were compared in an androgen-dependent prostate cancer cell model, LNCaP. The results demonstrated that MART-10 was 1,000-fold more active than 1alpha,25(OH)2D3 in inhibiting LNCaP cell proliferation. MART-10 was more active than 1alpha,25(OH)2D3 in up-regulating a vitamin D receptor-responsive Luciferase construct and inducing CYP24A1 gene expression in LNCaP prostate cancer cells. In addition, MART-10 has a lower affinity for DBP and less substrate degradation by CYP24A1 compared to 1alpha,25(OH)2D3, indicating that MART-10 has more bioavailability and a longer half-life. Thus, these data suggest that MART-10 may be a potential candidate as a therapeutic agent for prostate cancer, especially for patients who fail in conventional therapies.

Topics: Androgens; Base Sequence; Cell Line, Tumor; Cholecalciferol; DNA Primers; Humans; Male; Neoplasms, Hormone-Dependent; Polymerase Chain Reaction; Prostatic Neoplasms; RNA, Messenger; Steroid Hydroxylases; Vitamin D3 24-Hydroxylase

Analogs of 1,25-dihydroxyvitamin D3 with a reversed configuration at C-1 or C-24 and E or Z geometry of the double bond at C-22 in the side chain or at C-5 in the triene system were examined for their antiproliferative activity in vitro against a spectrum of various human cancer cell lines. The analogs coded PRI-2201 (calcipotriol), PRI-2202 and PRI-2205, such as calcitriol and tacalcitol (used as a referential agents), revealed antiproliferative activity against human HL-60, HL-60/MX2, MCF-7, T47D, SCC-25 and mouse WEHI-3 cancer cell lines. The toxicity studies in vivo showed that PRI-2202 and PRI-2205 are less toxic than referential agents. Even at total doses of 2.5-5.0 mg/kg distributed during 5 successive days, no changes in body weight were observed. Calcitriol and tacalcitol showed toxicity in the same protocol at 100 times lower doses. Calcipotriol was lethal to all mice after administration of a total dose of 5.0 mg/kg. The analog PRI-2205 appeared to be more active in mouse Levis lung cancer tumor growth inhibition than calcitriol, calcipotriol or PRI-2202. This analog did not reveal calcemic activity at doses which inhibit tumor growth in vivo nor at higher doses.

Topics: Animals; Antineoplastic Agents; Breast Neoplasms; Calcitriol; Calcium; Carcinoma, Lewis Lung; CD11b Antigen; Cell Cycle; Cell Differentiation; Cell Line, Tumor; Cell Proliferation; Cholecalciferol; Coloring Agents; Female; Fibroblasts; HL-60 Cells; Humans; Lipopolysaccharide Receptors; Male; Mice; Mice, Inbred C57BL; Mice, Inbred DBA; Pancreatic Neoplasms; Prostatic Neoplasms; Rhodamines; Stereoisomerism; Tetrazolium Salts; Thiazoles

The regulation of the human CYP27A1 gene by estrogens and androgens was studied in human liver-derived HepG2 and prostate cells. Our results show that the promoter activity, enzymatic activity and mRNA levels of CYP27A1 in HepG2 cells are downregulated by estrogen in presence of ERalpha or ERbeta. Similar effects by estrogen were found in RWPE-1 prostate cells. In contrast, estrogen markedly upregulated the transcriptional activity of CYP27A1 in LNCaP prostate cancer cells. 5alpha-Dihydrotestosterone and androgen receptor upregulated the transcriptional activity of CYP27A1 in HepG2 cells. Progressive deletion experiments indicate that the ERbeta-mediated effects in HepG2 and LNCaP cells are conferred to the same region (-451/+42) whereas ERalpha-mediated effects on this promoter are more complex. The results indicate that the stimulating effect of androgen in HepG2 cells is conferred to a region upstream from -792 in the CYP27A1 promoter. In summary, we have identified the human CYP27A1 gene as a target for estrogens and androgens. The results imply that expression of CYP27A1 may be affected by endogenous sex hormones and pharmacological compounds with estrogenic or androgenic effects.

Topics: Androgens; Base Sequence; Cell Line, Tumor; Cholecalciferol; Cholestanetriol 26-Monooxygenase; Dihydrotestosterone; Estrogens; Gene Expression Regulation, Neoplastic; Humans; Male; Molecular Sequence Data; Prostatic Neoplasms; Receptors, Androgen

25-Hydroxyvitamin D3-24-hydroxylase (24-hydroxylase, CYP24) is an important inactivating enzyme controlling the concentrations of both active metabolites 25-hydroxyvitamin D3 and 1alpha,25-dihydroxyvitamin D3. In this paper, we demonstrate that 25-hydroxyvitamin D3 at 500 nM significantly increases the expression of 24-hydroxylase mRNA and the increase is significantly decreased by 5alpha-dihydrotestosterone (DHT) at concentrations of 1-100 nM in androgen-sensitive prostate cancer cells LNCaP. 25-Hydroxyvitamin D3 at 500 nM and 1alpha,25-dihydroxyvitamin D3 at 10 nM inhibit LNCaP cell growth, and the growth inhibition is enhanced by 1 nM DHT. Neither 25-hydroxyvitamin D3 nor 1alpha,25-dihydroxyvitamin D3 at physiological concentrations has growth effect. However, in the presence of 1 nM DHT, both 25-hydroxyvitamin D3 and 1alpha,25-dihydroxyvitamin D3 at physiological concentrations are clearly antiproliferative. These data demonstrate that DHT enhances the antiproliferative activity of Vitamin D3 hormones by inhibiting their inactivating enzyme. Most previous studies on Vitamin D3 action in cell cultures have used pharmacological concentrations of 1alpha,25-dihydroxyvitamin D3, the present results demonstrate, for the first time, that both 25-hydroxyvitamin D3 and 1alpha,25-dihydroxyvitamin D3 at physiological concentrations are active in the presence of physiological concentration of androgen. The combined use of androgen and Vitamin D3 metabolites could be a promising treatment for prostate cancer.

Topics: Androgens; Cell Line, Tumor; Cell Proliferation; Cells, Cultured; Cholecalciferol; Dose-Response Relationship, Drug; Enzyme Inhibitors; Growth Inhibitors; Humans; Male; Prostate; Prostatic Neoplasms; Steroid Hydroxylases; Vitamin D3 24-Hydroxylase

The formal C-20 methylation of 1,25-dihydroxy vitamin D3 (calcitriol) and bridging of two methyl groups produces spiro[cyclopropane-1, 20'-calcitriol], colloquially referred to as C-20 cyclopropylcalcitriol, which is much more active in MLR for suppression of interferon-gamma release than calcitriol, and hypercalcemia in mice is elicited at a ten-fold lower dose when compared to calcitriol. Introduction of the Delta16,17-double bond, modification of the side chain by 23-unsaturation and replacement of the methyl groups at C-26 and C-27 with trifluoromethyl moieties create a highly active series of vitamin D analogs. As previously observed in the calcitriol series, the presence of the C-16 double bond in the cyclopropyl analogs also arrests metabolic side-chain oxidation in the at the C-24 oxo level in UMR 106 cells. The enhanced biological activity is ascribed, at least in part, to the improved resistance toward metabolic degradation.

Topics: Animals; Antineoplastic Agents; Cell Line, Tumor; Cholecalciferol; Humans; Male; Mice; Mice, Nude; Molecular Structure; Neoplasms, Experimental; Prostatic Neoplasms; Rats; Structure-Activity Relationship

Prostate cancer, the most commonly diagnosed cancer among American men, develops slowly over many years. The long latent period of 20 to 30 years, involved in the multistep process of carcinogenesis, provides an important opportunity to block or reverse progression to a malignant state. Vitamin A (retinoids) and vitamin D not only have the ability to block steps in the process of carcinogenesis but they can also modulate or reverse some malignant characteristics of cancer cells. However, at high levels, vitamins A and D have undesirable side effects, thus, limiting effective dose levels and efficacy. Therefore, combination treatment at low doses, to increase efficacy and avoid toxicity, is of special interest. This study examines the effects of the synthetic retinoid N-(4-hydroxyphenyl)retinamide (4-HPR) in combination with cholecalciferol (vitamin D3) on growth, and on the expression of vimentin, matrix metalloproteinase-2 (MMP-2), and retinoid and vitamin D receptor expression, using the non-tumorigenic, human prostate epithelial cell line RWPE-1. Treatment with 4-HPR and cholecalciferol resulted in synergistic growth inhibition when compared to that caused by each agent alone. A decrease in vimentin expression and MMP-2 activity, and up-regulation of vitamin D receptor (VDR) and some of the retinoid-X (RXRs) and retinoic acid receptor (RARs) subtypes, was observed. These results suggest that combined treatment with 4-HPR and cholecalciferol, at doses lower than what might be effective with single agents, increases their efficacy and suggest that this may serve as an effective strategy for chemoprevention and treatment of prostate cancer.

Topics: Anticarcinogenic Agents; Cholecalciferol; Drug Synergism; Fenretinide; Gene Expression Regulation, Neoplastic; Humans; Male; Matrix Metalloproteinase 2; Prostatic Neoplasms; Retinoids; Up-Regulation; Vimentin; Vitamins

Tumor-endothelial interaction contributes to local prostate tumor growth and distant metastasis. In this communication, we designed a novel approach to target both cancer cells and their "crosstalk" with surrounding microvascular endothelium in an experimental hormone refractory human prostate cancer model. We evaluated the in vitro and in vivo synergistic and/or additive effects of a combination of conditional oncolytic adenovirus plus an adenoviral-mediated antiangiogenic therapy. In the in vitro study, we demonstrated that human umbilical vein endothelial cells (HUVEC) and human C4-2 androgen-independent (AI) prostate cancer cells, when infected with an antiangiogenic adenoviral (Ad)-Flk1-Fc vector secreting a soluble form of Flk1, showed dramatically inhibited proliferation, migration and tubular formation of HUVEC endothelial cells. C4-2 cells showed maximal growth inhibition when coinfected with Ad-Flk1-Fc and Ad-hOC-E1, a conditional replication-competent Ad vector with viral replication driven by a human osteocalcin (hOC) promoter targeting both prostate cancer epithelial and stromal cells. Using a three-dimensional (3D) coculture model, we found that targeting C4-2 cells with Ad-hOC-E1 markedly decreased tubular formation in HUVEC, as visualized by confocal microscopy. In a subcutaneous C4-2 tumor xenograft model, tumor volume was decreased by 40-60% in animals treated with Ad-Flk1-Fc or Ad-hOC-E1 plus vitamin D3 alone and by 90% in a combined treatment group, compared to untreated animals in an 8-week treatment period. Moreover, three of 10 (30%) pre-established tumors completely regressed when animals received combination therapy. Cotargeting tumor and tumor endothelium could be a promising gene therapy strategy for the treatment of both localized and metastatic human prostate cancer.

Topics: Adenocarcinoma; Adenoviridae; Angiogenesis Inhibitors; Animals; Antineoplastic Combined Chemotherapy Protocols; Cell Line, Tumor; Cell Proliferation; Cholecalciferol; Endothelial Cells; Genetic Therapy; Genetic Vectors; Humans; Immunohistochemistry; Male; Mice; Mice, Nude; Microscopy, Confocal; Neoplasm Metastasis; Neovascularization, Pathologic; Osteocalcin; Promoter Regions, Genetic; Prostatic Neoplasms; Tetrazolium Salts; Thiazoles; Transplantation, Heterologous; Vascular Endothelial Growth Factor Receptor-2

When local treatments for prostate cancer have failed, and prostate-specific antigen (PSA) rises in the absence of symptoms, there is little consensus as to the best management strategy. Calcitriol has been shown to prolong the doubling time of PSA in this context, but near-toxic doses are required. We investigated the effect of the nutrient vitamin D (cholecalciferol), a biochemical precursor of calcitriol, on PSA levels and the rate of rise of PSA in these patients. Fifteen patients were given 2,000 IU (50 microg) of cholecalciferol daily and monitored prospectively every 2-3 mo. In 9 patients, PSA levels decreased or remained unchanged after the commencement of cholecalciferol. This was sustained for as long as 21 mo. Also, there was a statistically significant decrease in the rate of PSA rise after administration of cholecalciferol (P = 0.005) compared with that before cholecalciferol. The median PSA doubling time increased from 14.3 mo prior to commencing cholecalciferol to 25 mo after commencing cholecalciferol. Fourteen of 15 patients had a prolongation of PSA doubling time after commencing cholecalciferol. There were no side effects reported by any patient. Further study is needed to confirm this finding and to explore the potential therapeutic benefit of nutrient vitamin D in prostate cancer.

Topics: Administration, Oral; Aged; Calcitriol; Calcium Channel Agonists; Cholecalciferol; Follow-Up Studies; Humans; Male; Middle Aged; Neoplasm Recurrence, Local; Pilot Projects; Prospective Studies; Prostate-Specific Antigen; Prostatectomy; Prostatic Neoplasms; Treatment Outcome

The 20-30 year latency period for prostate cancer provides an important opportunity to prevent the development of invasive cancer. A logical approach for chemoprevention to reduce incidence is to identify agents, such as, vitamin D, which can inhibit cell proliferation and induce differentiation, are safe, and readily available to the public at low cost. Epidemiological evidence suggests that vitamin D deficiency is associated with increased risk for prostate cancer. We examined the ability and mechanisms of action of cholecalciferol (vitamin D(3)), a precursor of the most biologically active hormone calcitriol, to block or reverse premalignant changes. The immortalized, non-tumorigenic, RWPE-1 human prostate epithelial cell line, was used. Results show that cholecalciferol, at physiological levels: (i) inhibits anchorage-dependent growth (ii) induces differentiation by increasing PSA expression and (iii) exerts its effects by up-regulating vitamin D receptor (VDR), retinoid-X receptors (RXRs), and androgen receptor (AR). Furthermore, we discovered that human prostate epithelial cells constitutively express appreciable levels of 25-hydroxylase CYP27A1 protein, the enzyme which catalyzes the conversion of cholecalciferol to 25(OH)D(3), and that CYP27A1 is up-regulated by cholecalciferol. Recent studies show that human mitochondrial CYP27A1 can also catalyze 1alpha-hydroxylation of 25(OH)D(3) to calcitriol. The presence of 25-hydroxylase in human prostate epithelial cells has not previously been shown. Since human prostate epithelial cells have the necessary enzymes and the rare ability to locally convert cholecalciferol to the active hormone calcitriol, we propose that they are a prime target for chemoprevention of prostate cancer with cholecalciferol whose safety is well established as a supplement in vitamins and fortified foods.

Topics: Calcitriol; Cell Line, Tumor; Cell Proliferation; Chemoprevention; Cholecalciferol; Cholestanetriol 26-Monooxygenase; Dose-Response Relationship, Drug; Epithelial Cells; Humans; Male; Molecular Structure; Prostate-Specific Antigen; Prostatic Neoplasms; Receptors, Androgen; Receptors, Calcitriol; Retinoid X Receptors; Steroid Hydroxylases

Epidemiological evidence suggests an inverse relationship between prostate cancer and serum vitamin D levels. We examined the ability of cholecalciferol (vitamin D(3)), a calcitriol precursor, to inhibit or reverse cellular changes associated with malignant transformation and invasion and explored its mechanisms of action. The RWPE2-W99 human prostate epithelial cell line, which forms slow-growing tumors in nude mice, was used because it mimics the behavior of the majority of primary human prostate cancers. Cholecalciferol, at physiological levels: (i) inhibited anchorage-dependent and -independent growth; (ii) induced differentiation by decreasing vimentin expression with a concomitant decrease in motility/chemotaxis; (iii) decreased MMP-9 and MMP-2 activity with concomitant decrease in invasion; and (iv) exerted its effects by up-regulating vitamin D receptor (VDR), retinoid-X receptor-alpha (RXR-alpha), and androgen receptor (AR) in a dose-dependent manner. Furthermore, we found that RWPE2-W99 prostate cancer cells, similar to RWPE-1 cells (Tokar and Webber. Clin Exp Metast 2005; 22: 265-73), constitutively express the enzyme 25-hydroxylase CYP27A1 which is markedly up-regulated by cholecalciferol. Cholecalciferol has effects similar to those of calcitriol on growth, MMP activity, and VDR. The ability of CYP27A1 to catalyze the conversion of cholecalciferol to 25(OH)D(3) and of 25(OH)D(3) to calcitriol has been reported. RWPE2-W99 cells, similar to RWPE-1 cells, appear to have the rare ability to locally convert cholecalciferol to the active hormone calcitriol. Because it can inhibit cellular changes associated with malignant transformation and invasion, we propose that cholecalciferol may be an effective agent for the treatment of prostate cancer.

Topics: Calcitriol; Cell Line, Tumor; Cell Movement; Cell Proliferation; Chemotaxis; Cholecalciferol; Cholestanetriol 26-Monooxygenase; Colony-Forming Units Assay; Dose-Response Relationship, Drug; Humans; Male; Matrix Metalloproteinase 2; Matrix Metalloproteinase 9; Neoplasm Invasiveness; Prostatic Neoplasms; Receptors, Androgen; Receptors, Calcitriol; Receptors, Cytoplasmic and Nuclear; Retinoid X Receptors; Steroid Hydroxylases; Vimentin

Topics: Antineoplastic Agents, Phytogenic; Antineoplastic Combined Chemotherapy Protocols; Cholecalciferol; Docetaxel; Drug Administration Schedule; Humans; Male; Neoplasms, Hormone-Dependent; Prostatic Neoplasms; Randomized Controlled Trials as Topic; Survival Rate; Taxoids

To investigate whether prognosis of breast-, colon- and prostate cancer may be related to vitamin D(3), induced from solar ultra-violet (UV) radiation, through studies on geographical and seasonal variations in UV radiation.. This study includes 115,096 cases of breast-, colon- or prostate cancer, diagnosed between 1964 and 1992. Among these, 45,667 deaths due to the cancer were registered. On the basis of a north-south gradient in solar UV radiation and geographical climatic differences, Norway was divided into eight residential regions. According to seasonal variations in UV radiation, four periods of diagnosis during the year were used. Case fatality according to residential region and to season of diagnosis was estimated using Cox regression. The effects of occupational sun exposure, childbearing pattern and educational level were also evaluated.. No geographic variation in case fatality was observed for the three cancer types studied. A significant variation in prognosis by season of diagnosis was observed. Diagnoses during summer and fall, the seasons with the highest level of vitamin D(3), revealed the lowest risk of cancer death.. The results suggest that a high level of vitamin D(3) at the time of diagnosis, and thus, during cancer treatment, may improve prognosis of the three cancer types studied.

Topics: Breast Neoplasms; Cholecalciferol; Colonic Neoplasms; Educational Status; Female; Humans; Male; Norway; Occupational Exposure; Prognosis; Prostatic Neoplasms; Risk Factors; Seasons; Sunlight; Treatment Outcome

1alpha,25-dihydroxyvitamin D3 (vitamin D3) has been shown to upregulate p27Kip1 expression via Sp1 and NF-Y binding sites in the p27Kip1 promoter. However, whether vitamin D3 receptor (VDR) involves in this process is unclear. In this study, we demonstrated that expression of VDR in SW620 cells, which exhibited low level of endogenous VDR, increased vitamin D3-stimulated p27Kip1 promoter activity. On the contrary, suppression of Sp1 expression by small interference RNA reduced the stimulation of p27Kip1 promoter activity by vitamin D3 in LNCaP cells. DNA affinity precipitation assay and chromatin immunoprecipitation assay showed that VDR bound to the p27Kip1 promoter in vitro and in vivo. In addition, we also demonstrated that VDR interacted with Sp1 in vitro and in cells. Collectively, our results suggest that VDR is involved in the induction of p27Kip1 by vitamin D3 and may interact with Sp1 to modulate the expression of target genes that lack VDR response element (VDRE) in their promoters.

Topics: Base Sequence; Cell Cycle Proteins; Cell Line, Tumor; Cholecalciferol; Colonic Neoplasms; Cyclin-Dependent Kinase Inhibitor p27; DNA Primers; Genes, Reporter; Humans; Male; Promoter Regions, Genetic; Prostatic Neoplasms; Receptors, Calcitriol; Recombinant Fusion Proteins; RNA, Small Interfering; Sp1 Transcription Factor; Transfection; Tumor Suppressor Proteins

The antiproliferative effect of 1alpha,25(OH)(2)D(3) on human prostate cancer cells is well known, but the mechanism is still not fully understood, especially its androgen-dependent action. Based on cDNA microarray results, we found that long-chain fatty-acid-CoA ligase 3 (FACL3/ACS3) might play an important role in vitamin D(3) and androgen regulation of LNCaP cell growth. The expression of FACL3/ACS3 was found to be significantly upregulated by 1alpha,25(OH)(2)D(3) and the regulation was shown to be time-dependent, with the maximal regulation over 3.5-fold at 96h. FACL3/ACS3 was a dominant isoform of FACL/ACS expressed in LNCaP cells as indicated by measuring the relative expression of each isoform. 1alpha,25(OH)(2)D(3) had no significant effect on the expression of FACL1(FACL2), FACL4 and FACL6 except for its downregulation of FACL5 at 24 and 48h by around twofold. The upregulation of FACL3/ACS3 expression by 1alpha,25(OH)(2)D(3) was accompanied with increased activity of FACL/ACS as demonstrated by enzyme activity assay using a (14)C-labeled substrate preferential for FACL3/ACS3. The growth inhibitory effect of 1alpha,25(OH)(2)D(3) on LNCaP cells was significantly attenuated by FACL3/ACS3 activity inhibitor. Androgen withdrawal (DCC-serum), in the presence of antiandrogen Casodex or in AR-negative prostate cancer cells (PC3 and DU145), vitamin D(3) failed to regulate FACL3/ACS3 expression. The upregulation of FACL3/ACS3 expression by vitamin D(3) was recovered by the addition of DHT in DCC-serum medium. Western blot analysis showed that the expression of androgen receptor (AR) protein was consistent with vitamin D(3) regulation of FACL3/ACS3 expression. Taken together, the data suggest that the upregulation of FACL3/ACS3 expression by vitamin D(3) is through an androgen/AR-mediated pathway and might be one of the contributions of the vitamin D(3) antiproliferative effect in prostate cancer LNCaP cells.

Topics: Androgens; Base Sequence; Cholecalciferol; Coenzyme A Ligases; DNA Primers; Humans; Male; Prostatic Neoplasms

The vitamin D receptor (VDR) is a member of the steroid/retinoid receptor superfamily of nuclear receptors and has potential tumor-suppressive functions in prostate and other cancer types. Vitamin D3 (VD3) exerts its biological actions by binding within cells to VDR. The VDR then interacts with specific regions of the DNA in cells, and triggers changes in the activity of genes involved in cell division, cell survival, and cellular function. Using human primary cultures and the prostate cancer (PCa) cell line, ALVA-31, we examined the effects of VD3 under different culture conditions. Complete G0/G1 arrest of ALVA-31 cells and approximately 50% inhibition of tumor stromal cell growth was observed. To determine changes in gene expression patterns related to VD3 activity, microarray analysis was performed. More than approximately 20,000 genes were evaluated for twofold relative increases and decreases in expression levels. A number of the gene targets that were up- and down-regulated are related to potential mechanisms of prostatic growth regulation. These include estrogen receptor (ER), heat shock proteins: 70 and 90, Apaf1, Her-2/neu, and paxillin. Utilizing antibodies generated against these targets, we were able to confirm the changes at the protein level. These newly reported gene expression patterns provide novel information not only potential markers, but also on the genes involved in VD3 induced apoptosis in PCa.

Topics: Apoptotic Protease-Activating Factor 1; Cell Cycle; Cell Line, Tumor; Cell Proliferation; Cells, Cultured; Cholecalciferol; Cytoskeletal Proteins; DNA, Complementary; Down-Regulation; Estrogen Receptor alpha; Gene Expression Profiling; Gene Expression Regulation, Neoplastic; Heat-Shock Proteins; Humans; Male; Oligonucleotide Array Sequence Analysis; Paxillin; Phosphoproteins; Prostatic Neoplasms; Proteins; Proto-Oncogene Proteins c-bcl-2; Receptor, ErbB-2; Stromal Cells

FAS and FACL3 are enzymes of fatty acid metabolism. In our previous studies, we found that FAS and FACL3 genes were vitamin D3-regulated and involved in the antiproliferative effect of 1alpha,25(OH)2D3 in the human prostate cancer LNCaP cells. Here, we elucidated the mechanism behind the downregulation of FAS expression by vitamin D3. Triacsin C, an inhibitor of FACL3 activity, completely abolished the downregulation of FAS expression by vitamin D3, whereas an inhibitor of FAS activity, cerulenin, had no significant effect on the upregulation of FACL3 expression by vitamin D3 in LNCaP cells. In human prostate cancer PC3 cells, in which FACL3 expression is not regulated by vitamin D3, no regulation of FAS expression was seen. This suggests that the downregulation of FAS expression by vitamin D3 is mediated by vitamin D3 upregulation of FACL3 expression. Myristic acid, one of the substrates preferential for FACL3, enhanced the repression of FAS expression by vitamin D3. The action of myristic acid was abrogated by inhibition of FACL3 activity, suggesting that the enhancement in the downregulation of FAS expression by vitamin D3 is due to the formation of myristoyl-CoA. The data suggest that vitamin D3-repression of FAS mRNA expression is the consequence of feedback inhibition of FAS expression by long chain fatty acyl-CoAs, which are formed by FACL3 during its upregulation by vitamin D3 in human prostate cancer LNCaP cells.

Topics: Cell Line, Tumor; Cerulenin; Cholecalciferol; Coenzyme A Ligases; Down-Regulation; Enzyme Inhibitors; Fatty Acid Synthases; Gene Expression Regulation, Neoplastic; Humans; Male; Myristic Acid; Prostatic Neoplasms; Reverse Transcriptase Polymerase Chain Reaction; Time Factors; Triazenes; Up-Regulation

Parathyroid hormone-related protein (PTHrP) is expressed by prostate cancer cells. Since PTHrP increases the growth and enhances the osteolytic effects of prostate cancer cells, it is important to control the level of PTHrP expression in these cells. We show that 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) and its non-calcemic analogue, EB1089, suppress PTHrP mRNA and protein levels in the human prostate cancer cell lines PC-3 and LNCaP. The human PTHrP gene contains a sequence element homologous to the negative vitamin D response element within the parathyroid hormone gene. This DNA sequence (nVDRE(hPTHrP)) bound the vitamin D receptor (VDR) present in nuclear extracts from both PC-3 and LNCaP cells. However, when cloned upstream of the SV40 promoter and transiently transfected into PC-3 and LNCaP cells, nVDRE(hPTHrP) downregulated promoter activity in response to 1,25(OH)2D3 or EB1089 treatment in LNCaP, but not in PC-3, cells. These results may help to explain why some prostate cancers appear to be refractory to treatment with vitamin D analogues.

Topics: Base Sequence; Calcitriol; Cell Line, Tumor; Cholecalciferol; Down-Regulation; Drug Resistance, Neoplasm; Gene Expression Regulation, Neoplastic; Humans; Male; Parathyroid Hormone-Related Protein; Prostatic Neoplasms; RNA, Messenger; Sequence Homology, Nucleic Acid; Vitamin D Response Element

Breast and prostate cancer are leading causes of cancer death in the Western world. Hormone ablation is the primary therapy for invasive disease, but the tumour often recurs in an androgen or oestrogen receptor negative form for which novel therapies are sought urgently. The vitamin D receptor (VDR) may provide an important alternative therapeutic target. However, cancer cell line models from these tissues display a range of sensitivities to the antiproliferative effects of 1alpha,25dihydroxyvitamin D3 (1alpha,25(OH)2D3). The reason for apparent 1alpha,25(OH)2D3 insensitivity is currently unknown and we have investigated epigenetic mechanisms that may suppress the transcriptional activity of the VDR. Nuclear co-repressors have associated histone deacetylase (HDAC) activity, which keeps chromatin in a closed, transcriptionally silent state. We have found that the aggressive cancer cell lines with relative insensitivity to 1alpha,25(OH)2D3 have elevated nuclear co-repressor levels. For example, PC-3 prostate cancer cells have a significant 1.8-fold elevation in the co-repressor SMRT compared to normal epithelial cells (P < 0.05). We believe that a combination of elevated co-repressor level with reduced VDR content can cause 1alpha,25(OH)2D3 resistance. Consistent with this, we have shown that combining a low dose of HDAC inhibitor Trichostatin A (15 nM TSA) with 1alpha,25(OH)2D3 (100 nM) synergistically inhibits the proliferation of PC-3 prostate and MDA-MB-231 breast cancer cell lines. The inhibition of proliferation was potentiated further by treating cells with 19-nor-hexafluoride vitamin D3 analogues instead of 1alpha,25(OH)2D3, plus TSA. For example, the combination of 1alpha,25(OH)2D3 and TSA-inhibited MDA-MB-231 cell proliferation by 38% (+/-5%), whereas Ro26-2198 (1alpha,25-(OH)2-16,23Z-diene-26,27-F6-19-nor-D3) and TSA inhibited growth by 62% (+/-2%). Therapeutically the hypercalcaemic side effects associated with 1alpha,25(OH)2D3 could be minimized by combining low doses of potent 1a,25(OH)2D3 analogues with HDAC inhibitors as a novel anticancer regime for hormone-insensitive prostate and breast cancer.

Topics: Androgens; Antineoplastic Agents; Breast Neoplasms; Cell Division; Cholecalciferol; DNA-Binding Proteins; Drug Synergism; Enzyme Inhibitors; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Ligands; Male; Neoplasms, Hormone-Dependent; Nuclear Receptor Co-Repressor 2; Prostatic Neoplasms; Repressor Proteins; Tumor Cells, Cultured; Vitamin D

In this study, we have characterized a novel less-calcemic vitamin D analog Ro 25-4020 (1alpha, 25 dihydroxy-16-ene-5,6-trans-vitamin D3) and investigated the mechanisms underlying its enhanced growth inhibitory properties. We found that Ro 25-4020 (IC50 = 0.3 nM) exhibited greater inhibitory activity than 1,25(OH)2D3 (IC50 = 1 nM) on LNCaP human prostate cancer cell growth. However, Ro 25-4020 was tenfold less active than 1,25(OH)2D3 in receptor-binding assays, ligand-induced heterodimerization and transactivation assays using VDR. HPLC and GC-MS analyses revealed that 1,25(OH)2D3 is converted to a 24-hydroxy metabolite, which has been shown to be less potent than 1,25(OH)2D3. In contrast, Ro 25-4020 was converted to a major 24-oxo metabolite that was more stable. Ligand-binding assays reveal that both Ro 25-4020 and its 24-oxo metabolite have similar affinity for VDR. Synthetic 24-oxo-Ro 25-4020, however, inhibited LNCaP cell proliferation as potently as 1,25(OH)2D3 and was more potent in transactivation of two out of three vitamin D target genes tested. These results suggest that conversion of Ro 25-4020 into an active and more stable 24-oxo metabolite with longer half-life contributes significantly to its potent antiproliferative actions on the LNCaP cells.

Topics: Animals; Calcitriol; Cell Differentiation; Cell Division; Chlorocebus aethiops; Cholecalciferol; Chromatography, High Pressure Liquid; COS Cells; Gas Chromatography-Mass Spectrometry; Humans; Luciferases; Male; Osteocalcin; Prostate-Specific Antigen; Prostatic Neoplasms; Receptors, Calcitriol; Receptors, Retinoic Acid; Saccharomyces cerevisiae; Transcription, Genetic; Transcriptional Activation; Tumor Cells, Cultured; Two-Hybrid System Techniques

Osteocalcin (OC) is a small (6 kDa) polypeptide whose expression was thought to be limited to mature osteoblasts. The discovery of OC expression in prostate cancer specimens led us to study the regulation of OC gene in androgen-independent metastatic human prostate PC3 cells. An 800-bp human OC (hOC) promoter-luciferase construct exhibited strong basal and vitamin D-induced activity in OC-positive human prostate and osteosarcoma cell lines. Through deletion analysis of the hOC promoter, the functional hierarchy of the cis-acting elements, OSE1, OSE2, and AP-1/VDRE, was established in PC3 cells (OSE1 > AP-1/VDRE > OSE2). By juxtaposing dimers of these 3 cis-elements, we produced a minimal hOC promoter capable of displaying high tissue specific activity in prostate cancer cells. Our study demonstrated three groups of transcription factors, Runx2, JunD/Fra-2, and Sp1, responsible for the high hOC promoter activity in PC3 cells by binding to the OSE2, AP-1/VDRE, and OSE1 elements, respectively. Among the three groups of transcription factors, the expression levels of Runx2 and Fra-2 are higher in the OC-positive PC3 cells and osteoblasts, compared with the OC-negative LNCaP cells. Interestingly, unlike the mouse OC promoter, the OSE1 site in hOC promoter is regulated by members of Sp1 family instead of the osteoblast-specific factor Osf1. The molecular basis for androgen-independent prostate cancer cells behaving like mature osteoblasts may be explained by the interplay and coordination of these transcription factors under the tight regulation of autocrine and paracrine mediators.

Topics: Base Sequence; Blotting, Western; Cell Nucleus; Cholecalciferol; Core Binding Factor Alpha 1 Subunit; Dimerization; Electrophoresis, Polyacrylamide Gel; Gene Deletion; Humans; Luciferases; Male; Models, Biological; Molecular Sequence Data; Neoplasm Proteins; Osteocalcin; Osteosarcoma; Plasmids; Promoter Regions, Genetic; Prostatic Neoplasms; Proto-Oncogene Proteins c-jun; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Sequence Homology, Nucleic Acid; Sp1 Transcription Factor; Transcription Factors; Transcription, Genetic; Transfection; Tumor Cells, Cultured

We report the development of a novel replication-competent adenoviral vector, Ad-hOC-E1, containing a single bidirectional human osteocalcin (hOC) promoter to drive both the early viral E1A and E1B gene. This vector selectively replicated in OC-expressing but not non-OC-expressing cells, with viral replication enhanced at least 10-fold on vitamin D(3) exposure. Both the artificial TATA-box and hOC promoter element in this bidirectional promoter construct were controlled by a common OC regulatory element which selectively activated OC expression in cells. The expression ofE1A and E1B gene by Ad-hOC-E1 can be markedly induced by vitamin D(3). Unlike Ad-sPSA-E1, an adenoviral vector with viral replication controlled by a strong super prostate-specific antigen (sPSA) promoter which only replicates in PSA-expressing cells with androgen receptor (AR), Ad-hOC-E1 retarded the growth of both androgen-dependent and androgen-independent prostate cancer cells irrespective of their basal level of AR and PSA expression. A single i.v. administration of 2 x 10(9) plaque-forming units of Ad-hOC-E1 inhibited the growth of previously established s.c. DU145 tumors (an AR- and PSA-negative cell line). Viral replication is highly enhanced by i.p. administration of vitamin D(3). Ultimately, enhancing Ad-hOC-E1 viral replication by vitamin D(3) may be used clinically to treat localized and osseous metastatic prostate cancer in men.

Topics: Adenoviridae; Adenovirus E1A Proteins; Adenovirus E1B Proteins; Cell Division; Cholecalciferol; Genetic Therapy; Genetic Vectors; Humans; Male; Osteocalcin; Prostatic Neoplasms; RNA, Messenger; Up-Regulation; Virus Replication

Prostate cancer is a major cause of male cancer death. In vitro and in vivo data support a role for 1 alpha,25 Dihydroxyvitamin D(3) (1 alpha,25(OH)(2)D(3)) in regulating the growth and differentiation of the normal prostate gland yet prostate cancer cells appear significantly less sensitive to this action. Vitamin D(3) receptor (VDR) content or mutational status do not correlate clearly with the antiproliferative effects of 1 alpha,25(OH)(2)D(3) and therefore it is unclear why prostate cancer cell lines are significantly less sensitive to this action. We hypothesized that the antiproliferative responses of prostate cancer cells to 1 alpha,25(OH)(2)D(3) are suppressed by a process involving histone deacetylation. Sodium butyrate (NaB) and trichostatin A (TSA) are inhibitors of histone deacetylase (HDAC) activity. Low doses of NaB or TSA (300 microM and 15 nM respectively), which alone were relatively inactive, synergized with 1 alpha,25(OH)(2)D(3) in liquid and semi-solid agar to inhibit the growth of LNCaP, PC-3 and DU-145 prostate cancer cells. Still greater synergy was observed between vitamin D(3) hexafluoride analogs and either NaB or TSA. The mechanism appeared to involve neither the cyclin-dependent kinase inhibitor, p21((waf1/cip1)) nor cell cycle arrest, but rather induction of apoptosis. These data suggest that cells dysregulate the normal pro-apoptotic signals of 1 alpha,25(OH)(2)D(3) during prostate cancer development by a mechanism involving histone deacetylation. Combination therapy with potent vitamin D(3) analogs and clinically approved HDAC inhibitors may overcome this lesion and improve the treatment of both androgen-dependent and independent prostate cancer.

Topics: Antineoplastic Agents; Apoptosis; Butyric Acid; Calcitriol; Cell Cycle; Cholecalciferol; Cyclin-Dependent Kinase Inhibitor p21; Cyclins; Cytochrome P-450 Enzyme System; Drug Synergism; Enzyme Inhibitors; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Male; Prostatic Neoplasms; Steroid Hydroxylases; Transcriptional Activation; Tumor Cells, Cultured; Vitamin D3 24-Hydroxylase

We attempted to provide experimental evidence linking increased dietary calcium to progression of prostate cancer, as suggested by some epidemiological studies, using a heterotopic prostate cancer nude mice model.. Twenty heterotopic LNCaP prostate cancer tumor bearing nude mice were randomly assigned to one of the four groups: (I) high fat/low calcium diet, (II) high fat and high calcium diet, (III) high fat diet fortified with Vitamin D3, and (IV) high fat and high calcium diet fortified with Vitamin D3. In addition to weekly animal weights and tumor size measurements, the serum prostate specific antigen (PSA), 25-hydroxy Vitamin D3, calcium, phosphorus, total protein, albumin (to account for bound calcium) [1], and serum alkaline phosphatase (a measure of bone loss) [2] were determined at the termination of experiments.. Although the serum calcium and 25-hydroxy Vitamin D3 were significantly higher in groups III and IV compared to groups I and II (P < 0.05), there was no significant difference between the tumor growth rates, final tumor weights (P = 0.9), and the serum PSA levels (P = 0.94) between the four groups.. The results suggest that dietary calcium does not significantly affect the growth of heterotopic LNCaP prostate cancer in nude mice.

Topics: Adenocarcinoma; Alkaline Phosphatase; Animals; Blood Proteins; Body Weight; Calcifediol; Calcium; Calcium, Dietary; Cell Division; Cholecalciferol; Dietary Fats; Disease Progression; Humans; Male; Mice; Mice, Nude; Neoplasms, Hormone-Dependent; Phosphorus; Prostate-Specific Antigen; Prostatic Neoplasms; Random Allocation; Serum Albumin

Topics: Adenocarcinoma; Aged; Bone Neoplasms; Cholecalciferol; Disease Progression; Fatal Outcome; Flutamide; Humans; Male; Osteomalacia; Phosphates; Potassium Compounds; Prostate-Specific Antigen; Prostatic Neoplasms; Tomography, X-Ray Computed

The majority of men who die from prostate cancer (PC) have hormone-refractory disease. To date, chemotherapeutic agents have had little or no impact on the survival of such patients. To explore a new approach for the treatment of hormone-refractory PC, we examined the combination effects of cis- or carboplatin with vitamin D. 1alpha,25-Dihydroxyvitamin D3 (1alpha,25(OH)2D3) and its synthetic analogue, Ro 25-6760, have an antiproliferative effect on some prostate cancer cell lines. Consequently, the growth-inhibitory effects of the drugs were measured, both singularly and in combination with cis- or carboplatin, on PC cells. Our results show that although each of the drugs alone displayed antiproliferative activity, the growth inhibition of PC cells was further enhanced by the combination of 1alpha,25(OH)2D3 or Ro 25-6760 and either platinum agent. The greatest enhancement of inhibition occurred using smaller concentrations of the platinum compound in combination with higher concentrations of 1alpha,25(OH)2D3. Isobologram analysis revealed that 1alpha,25(OH)2D3 and platinum acted in a synergistic manner to inhibit the growth of PC cells. Our findings suggest that there is potential clinical value in combining 1alpha,25(OH)2D3 with platinum compounds for the treatment of advanced-stage human PC.

Topics: Anticarcinogenic Agents; Antineoplastic Agents; Calcitriol; Carboplatin; Cell Cycle; Cell Division; Cholecalciferol; Cisplatin; Dose-Response Relationship, Drug; Drug Synergism; Humans; Male; Platinum; Prostatic Neoplasms; Tumor Cells, Cultured

The secosteroid hormones, all-trans- and 9-cis-retinoic acid and vitamin D3, have demonstrated significant capacity to control proliferation in vitro of many solid tumour cell lines. Cooperative synergistic effects by these two ligands have been reported, and it is, therefore, possible that greater therapeutic effects could be achieved if these compounds were administered together. The role of retinoid-dependent anti-activator protein 1 (anti-AP-1) effects in controlling cancer cell proliferation appears significant. We have utilized an anti-AP-1 retinoid [2-(4,4-dimethyl-3,4-dihydro-2H-1 benzopyran-6-yl)carbonyl-2-(4-carboxyphenyl)-1,3,-dithiane; SR11238], which does not transactivate through a retinoic acid response element (RARE), and a potent vitamin D3 analogue [1alpha,25(OH)2-16-ene-23-yne-26,27-F6-19-nor-D3, code name LH] together at low, physiologically safer doses against a panel of prostate cancer cell lines that represent progressively more transformed phenotypes. The LNCaP (least transformed) and PC-3 (intermediately transformed) cell lines were synergistically inhibited in their clonal growth by the combination of LH and SR11238, whereas SR11238 alone was essentially inactive. DU-145 cells (most transformed) were completely insensitive to these analogues. LNCaP cells, but neither PC-3 nor DU-145, underwent apoptosis in the presence of LH and SR11238. Transactivation of the human osteocalcin vitamin D response element (VDRE) by LH was not enhanced in the presence of SR11238, although the expression of E-cadherin in these cells was additively up-regulated in the presence of both compounds. These data suggest the anti-AP-1 retinoid and the vitamin D3 analogue may naturally act synergistically to control cell proliferation, a process that is interrupted during transformation, and that this combination may form the basis for treatment of some androgen-independent prostate cancer.

Topics: Antineoplastic Agents; Apoptosis; Cadherins; Cell Division; Cholecalciferol; Cyclin-Dependent Kinase Inhibitor p21; Cyclins; Humans; Male; Prostatic Neoplasms; Retinoids; Tretinoin; Tumor Cells, Cultured

The 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] is the physiologically active form of vitamin D3 that inhibits proliferation and induces differentiation of a variety of malignant cells. We evaluated a newly synthesized vitamin D3 analogue [1,25(OH)2-16-ene-5,6-trans-D3 (Ro 25-4020)] that has a novel 5,6-trans motif. Dose-response studies showed that 1,25(OH)2-16-ene-5,6-trans-D3 had 10-100-fold greater antiproliferative activities than 1,25(OH)2D3 when measuring clonal growth of breast (MCF-7) and prostate (LNCaP) cancer cell lines as well as a myeloid leukemia cell line (HL-60). Because the chief toxicity of vitamin D3 is hypercalcemia, we examined the calcemic activity of 1,25(OH)2-16-ene-5,6-trans-D3 in mice. Remarkably, 1,25(OH)2-16-ene-5,6-trans-D3 was at least 40-fold less calcemic as compared with 1,25(OH)2D3 and 1,25(OH)2-16-ene-D3 (Ro 24-2637). To explore the mechanism by which the 1,25(OH)2-16-ene-5,6-trans-D3 analogue mediated its antiproliferative activity, several studies were performed. Pulse-exposure studies showed that a 4-day pulse exposure to 1,25(OH)2-16-ene-5,6-trans-D3 (10(-7) M) in liquid culture was adequate to achieve a 40% inhibition of MCF-7 clonal growth in the absence of the analogue, suggesting that the growth inhibition mediated by 1,25(OH)2-16-ene-5,6-trans-D3 was at least in part irreversible. Cell cycle studies showed that 1,25(OH)2-16-ene-5,6-trans-D3 increased the proportion of MCF-7 cells in the G0-G1 phase and decreased those in the S phase. Furthermore, 1,25(OH)2-16-ene-5,6-trans-D3 induced an elevated expression of the cyclin-dependent kinase inhibitors, p21waf1 and p27kip1. In addition, 1,25(OH)2-16-ene-5,6-trans-D3 almost completely inhibited telomerase activity, as measured by telomeric repeat amplification protocol assay and human telomerase reverse transcriptase mRNA. For each of the growth-related parameters that were examined, the vitamin D3 analogue was more active than 1,25(OH)2D3. In contrast, 1,25(OH)2D3 was more calcemic than 1,25(OH)2-16-ene-5,6-trans-D3. In summary, 1,25(OH)2-16-ene-5,6-trans-D3, having a novel 5,6-trans motif, strongly inhibited clonal proliferation and reduced telomerase activity with low calcemic activity, suggesting further testing in in vivo cancer models. This analogue may gain a therapeutic niche for selected malignancies.

Topics: Animals; Antineoplastic Agents; Breast Neoplasms; Cell Division; Cholecalciferol; Female; Humans; Leukemia, Myeloid; Male; Mice; Prostatic Neoplasms; Tumor Cells, Cultured

Retinoids and analogs of vitamin D3 may achieve greater in vivo applications if the toxic side effects encountered at pharmacologically active doses could be alleviated. These seco-steroid hormones often act in concert, and therefore, we attempted to dissect these interactions by isolating combinations of receptor-selective retinoids and a potent vitamin D3 analog [1alpha,25(OH)2-16ene-23-yne-26,27,F6-19nor-D3, code name LH] that were potent inhibitors of prostate cancer cell growth at low, physiologically safer doses. Using a panel of prostate cancer cell lines representing progressively more transformed phenotypes, we found that the LNCaP cell line (least transformed) was either additively or synergistically inhibited in its clonal growth by LH and various naturally occurring and receptor-selective retinoids, the most potent combination being with a retinoic acid receptor (RAR)betagamma-selective retinoid (SR11262). The effect was not found with either PC-3 (intermediate transformation) or DU-145 (most transformed). We also undertook RT-PCR to examine the subtypes of RARs present, and we found that PC-3 and DU-145 did not express RARbeta. Stable expression of RARbeta into the RARbeta-negative PC-3 cells resulted in increased sensitivity to SR11262 and LH proportional to the amount of RARbeta expressed. This study indicates that RARbeta may play an important role in synergistically controlling cell proliferation, and expression is lost with increased prostate cancer cell transformation. Simultaneous administration of a potent vitamin D3 analog and receptor-selective retinoids may have therapeutic potential for the treatment of androgen-dependent and -independent prostate cancer.

Topics: Apoptosis; Cell Division; Cholecalciferol; Culture Media; Gene Expression; Humans; Male; Polymerase Chain Reaction; Prostatic Neoplasms; Receptors, Retinoic Acid; Retinoids; RNA-Directed DNA Polymerase; Tumor Cells, Cultured

Management of prostate cancer that has spread outside of the prostate capsule is a difficult problem. Innovative, non-toxic approaches to the disease are required. New, relatively non-toxic vitamin D3 analogs have recently been synthesized. We report that several of these compounds have marked antiproliferative effects on prostate cells.. The clonal antiproliferative activity of five novel analogs of 1,25 dihydroxyvitamin D3 [1,25(OH)2D3, (cmpd C)] as well as 1,25(OH)2D3 itself was tested on three human prostate cancer cell lines (PC-3, LNCaP, and DU-145). The analogs were 20-epi-22oxa-24a,26a,27a-tri-homo-1 alpha,25(OH)2D3 (code name: KH 1060); 24a26a27a-tri-homo-22,24-diene-1 alpha,25(OH)2D3 (code name: EB 1089); 1,25(OH)2-16ene-D3 (code name: HM); 1,25(OH)2-16ene-23yne-D3 (code name: V); 1,25(OH)2-20-epi-D3 (code name: MC 1288)].. With the parent compound [1,25(OH)2D3], the effective dose that inhibited 50% clonogenic growth of PC-3 and LNCaP was 10(-8)M and 7 x 10(-9)M, respectively. For these prostate cancer cell lines, KH 1060 was the most potent analog by an order of 25- to 35-fold as compared to cmpd C. The second and third most potent analogs were HM and MC 1288. DU-145 was resistant to all the vitamin D3 analogs. The major side-effect of 1,25(OH)2D3 is the production of hypercalcemia. The relative inhibitory index (RII) was determined by comparing the antiproliferative activity of the analog to its ability to produce hypercalcemia in mice injected intraperitoneally every other day. The KH 1060 had the best RTI: 50- to 70-fold greater than 1,25(OH)2D3 for PC-3 and LNCaP, respectively.. A trial of one or more of these innovative compounds should be considered for treatment of minimal residual disease of prostate cancer.

Topics: Animals; Antineoplastic Agents; Calcitriol; Calcium; Cell Division; Cholecalciferol; Humans; Male; Mice; Mice, Inbred BALB C; Prostatic Neoplasms; Tumor Cells, Cultured

The seco-steroid hormone, 1 alpha, 25 dihydroxyvitamin D3 (1 alpha,25(OH)2D3) binds to a specific nuclear receptor that acts as a ligand-inducible transcription factor. The resulting genomic effects include partial arrest in G0/G1 of the cell cycle and induction of differentiation; these effects have been observed in various types of cancer. Recently, we produced enzymatically the natural 24-oxo metabolites of 1 alpha,25(OH)2D3 and two of its potent synthetic analogs (1 alpha,25-(OH)2-16-ene-D3 and 1 alpha,25-(OH)2-20-epi-D3) using a rat kidney perfusion system. We have found that the 24-oxo metabolites of both 1 alpha,25(OH)2D3 and its analogs have either the same or greater antiproliferative activity against various cancer cells as their parental compounds. Notably, two cell lines (DU-145 (prostate cancer) and MDA-MB-436 [breast cancer]) that were extremely resistant to the antiproliferative effects of vitamin D3 analogs displayed greater sensitivity towards the 24-oxo metabolite of the vitamin D3 analog. Similarly, the 24-oxo metabolites had the capacity to induce differentiation and apoptosis and to diminish the proportion of cells in S phase. Most interestingly, while the analog 1 alpha,25(OH)2-20-epi-D3 induced expression of BRCA1 in MCF-7 breast cancer cells; its 24-oxo metabolite dramatically suppressed BRAC1 expression. Thus, we have shown for the first time that the various biological activities produced by the hormone 1 alpha,25(OH)2D3 and some of its analogs may represent a combination of actions by the hormone 1 alpha,25(OH)2D3 and its natural 24-oxo metabolites.

Topics: Apoptosis; bcl-2-Associated X Protein; BRCA1 Protein; Breast Neoplasms; Cadherins; Calcitriol; Cell Cycle; Cell Cycle Proteins; Cell Division; Cholecalciferol; Cyclin-Dependent Kinase Inhibitor p21; Cyclin-Dependent Kinase Inhibitor p27; Cyclins; HL-60 Cells; Humans; Male; Microtubule-Associated Proteins; Neoplasms; Prostatic Neoplasms; Proto-Oncogene Proteins; Proto-Oncogene Proteins c-bcl-2; Tumor Cells, Cultured; Tumor Suppressor Proteins

We have synthesized and studied the ability of a series of seven novel 1 alpha,25(OH)2 vitamin D3 analogues to inhibit clonal growth of prostate cancer cells (LNCaP, PC-3 and DU-145). Addition of double and triple bonds to the C/D ring (C-16) and side chain (C-22 and C-23) as well as lengthening of the side chain were important for enhanced activity against LNCaP and PC-3. Reorientation of the side chain in the 20-epi configuration resulted in analogues that were extremely potent only against LNCaP (ED50 approximately 5 x 10(-11) M). Compounds with six fluorines on the end of the side chain were very active against both PC-3 and LNCaP (ED50 approximately 2 x 10(-8) M). DU-145 cells were relatively resistant to compounds with all of these modifications, but removal of C-19 (e.g. 1,25(OH)2-16-ene-23-yne-26,27-F6-19-nor-D3) resulted in an analogue that was inhibitory against all three prostate cell lines. Further analysis showed that pulse exposure (3 days, 10(-7) M) to this analogue was enough to inhibit clonal growth of PC-3 cells by 50%. The same exposure also induced cell cycle arrest of all three cell lines, accompanied by upregulated protein expression of the cyclin-dependent kinase inhibitor (CDKI) known as p21waf1 in all three cell lines, and the CDKI known as p27kip1 in LNCaP cells. Associated with upregulation of these CDKIs, partial differentiation occurred as measured by increased expression of both prostate-specific antigen by LNCaP cells and E-cadherin, a cell adhesion protein that may act as a putative tumour suppressor (LNCaP and PC-3 cells). In summary, this is the first report of a potent series of 19-nor-vitamin D3 analogues with the ability to inhibit proliferation of LNCaP, PC-3 and DU-145 prostate cancer cell lines. These compounds may mediate their potent anti-proliferative activities through a cell cycle arrest pathway.

Topics: Antineoplastic Agents; Apoptosis; Cadherins; Cell Cycle; Cell Cycle Proteins; Cell Differentiation; Cell Division; Cholecalciferol; Cyclin-Dependent Kinase Inhibitor p21; Cyclin-Dependent Kinase Inhibitor p27; Cyclins; Humans; Male; Microtubule-Associated Proteins; Prostate-Specific Antigen; Prostatic Neoplasms; Structure-Activity Relationship; Tumor Cells, Cultured; Tumor Suppressor Proteins

The principal cause of death from most forms of cancer is metastatic disease. Cancer cells appear to grow quickly out of the control of the normal host regulatory mechanisms. Many factors contribute to this unrestrained proliferation, including increased metalloproteinase activity causing degradation of the extracellular matrix surrounding cancer cells, angiogenesis permitting easy access of the cells to the bloodstream and decrease or loss of programmed cell death, or apoptosis, an important mechanism for removal of abnormal or senescent cells. Treatment modalities targeted towards arresting cancer cell proliferation and spread are needed to improve the survival of patients with cancer. Vitamin D3, 1,25-dihydroxychole-calciferol D3, has been shown to induce apoptosis in the human breast cancer cell line, MCF-7. We have studied the effects of three concentrations of vitamin D3 on the human breast cancer cell line, MDA-MB-435, the human prostate cancer cell line, LNCaP, and a human osteosarcoma cell line, U20S. We report here that vitamin D3 strikingly inhibits cell proliferation and induces apoptosis in all three cell lines.

Topics: Adenocarcinoma; Apoptosis; Breast Neoplasms; Cell Division; Cholecalciferol; Dose-Response Relationship, Drug; Female; Humans; Male; Neoplasm Proteins; Osteosarcoma; Prostatic Neoplasms; Tumor Cells, Cultured

Data from epidemiological studies has suggested that vitamin D deficiency may promote prostate cancer, although the mechanism is not understood. We have previously demonstrated the presence of vitamin D receptors (VDR) in three human prostate carcinoma cell lines (LNCaP, PC-3, and DU-145) as well as in primary cultures of stromal and epithelial cells derived from normal and malignant prostate tissues. We have also shown that 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3] can elicit an antiproliferative action in these cells. In the present study we compared the biological actions of 1,25-(OH)2D3 to those of a series of natural vitamin D3 metabolites and several synthetic analogs of vitamin D3 known to exhibit less hypercalcemic activity in vivo. In ligand binding competition experiments, we demonstrated the following order of potency in displacing [3H]1,25-(OH)2D3 from VDR: EB-1089 > 1,25-(OH)2D3 > MC-903 > 1,24,25-(OH)3D3 > 22-oxacalcitriol (OCT) > 1 alpha,25-dihydroxy-16-enecholecalciferol (Ro24-2637) > 25-hydroxyvitamin D3, with EB-1089 being approximately 2-fold more potent than the native hormone. No competitive activity was found for 25-hydroxy-16,23-diene-cholecalciferol. When compared for ability to inhibit proliferation of LNCaP cells, MC-903, EB-1089, OCT, and Ro24-2637 exhibited 4-, 3-, and 2-fold greater inhibitory activity than 1,25-(OH)2D3. Interestingly, although OCT and Ro24-2637 exhibit, respectively, 10 and 14 times lower affinity for VDR than 1,25-(OH)2D3, both compounds inhibited the proliferation of LNCaP cells with a potency greater than that of the native hormone. The relative potency of vitamin D3 metabolites and analogs to inhibit cell proliferation correlated well with the ability of these compounds to stimulate prostate-specific antigen secretion by LNCaP cells as well as with their potency to induce the 25-hydroxyvitamin D3-24-hydroxylase messenger RNA transcript in PC-3 cells. In conclusion, these results demonstrate that synthetic analogs of vitamin D3, known to exhibit reduced calcemic activity, can elicit antiproliferative effects and other biological actions in LNCaP and PC-3 cell lines. It is noteworthy that although binding to VDR is critical for 1,25-(OH)2D3 action, the analog data indicate that additional factors significantly contribute to the magnitude of the biological response. Finally, the strong antiproliferative effects of several synthetic analogs known to exhibit less calcemic activity than 1,25-(OH)2D3 suggest that

Topics: Binding Sites; Calcitriol; Carcinoma; Cell Division; Cholecalciferol; Cytochrome P-450 Enzyme System; Humans; Male; Prostate-Specific Antigen; Prostatic Neoplasms; Receptors, Calcitriol; RNA, Messenger; Steroid Hydroxylases; Tumor Cells, Cultured; Vitamin D3 24-Hydroxylase

Topics: Biopsy; Bone Neoplasms; Calcitonin; Calcium; Cholecalciferol; Humans; Hypocalcemia; Intestinal Absorption; Male; Middle Aged; Neoplasm Metastasis; Osteomalacia; Phosphorus; Prostatic Neoplasms