fenretinide and Lung-Neoplasms

Topics: Biomarkers, Tumor; Cell Division; DNA Replication; Drug Design; Fenretinide; Humans; Lung Neoplasms; Telomerase; Telomere

There is a clear change in the treatment strategies for solid tumours towards the treatment of early rather than advanced disease. Retinoids represent a potentially useful class of drugs in chemoprevention. Preclinical data and clinical experience suggests that different retinoids may have different spectra of antitumour activity and synergistic interactions between retinoids and cytokines have also been reported. 13-cis retinoic acid has shown some promising activity in preventing the onset of second primary tumours in head and neck cancer and fenretinide is being tested in the prevention of second primary breast cancers. An understanding fo the role of the different retinoid receptors could lead to the design of compounds with a better therapeutic index. Despite these early indications that retinoids could be useful in this area, the development of such drugs is far from easy. Appropriate study designs for screening differentiating agents in the clinic, and the relevance of preclinical models of chemoprevention are challenges to be addressed. Unresolved issues include optimal patient selection, long clinical trial times, optimal dose, schedule and treatment duration. The use of biological surrogate markers for longer time-dependent trial endpoints could significantly contribute to more rapid development. Ongoing clinical studies, particularly in tobacco-related diseases, will better define the role of retinoids in this clinical setting. Clinicians should be encouraged to enter patients into large well organized clinical studies.

Topics: Breast Neoplasms; Female; Fenretinide; Head and Neck Neoplasms; Humans; Isotretinoin; Lung Neoplasms; Male; Neoplasms; Retinoids; Risk Factors

Alterations in retinoid signaling appear to be involved in the pathogenesis of small cell lung cancer (SCLC). Fenretinide [N-(4-hydroxyphenyl)retinamide], a synthetic retinoid, inhibits the growth of SCLC cells in vitro via the induction of apoptosis. Since these data suggested that SCLC is the adult solid tumor that is most susceptible to fenretinide, a trial to evaluate the clinical activity of fenretinide in patients with SCLC was considered the definitive test of its clinical potential in adult oncology.. Patients with progressive SCLC after one or two prior chemotherapy regimens and a performance status of 0-2 were eligible for the study. Patients with stable, treated brain metastases were eligible. Fenretinide 900 mg/m(2) twice daily was administered orally on days 1-7 of each 21-day cycle. Blood and saliva were collected pre-treatment and on day 7 of cycle 1 to measure fenretinide and retinol levels by high-pressure liquid chromatography (HPLC).. Nineteen patients were enrolled. Fifteen patients had one prior chemotherapy regimen and four patients had two prior regimens. The median time from diagnosis to enrollment was 10 months. A median of two cycles of fenretinide was administered. There were no objective responses, but four of 17 evaluable patients (24%) had stable disease after 2-17 cycles. The median time to treatment failure was 5.7 weeks overall, while the four patients with stable disease demonstrated treatment failure at 11, 13, 19, and 52 weeks. Median survival was 25 weeks, with one patient alive 22 months after the start of treatment. The 1-year survival rate was 29%. Toxicity included mild, reversible visual changes (haziness, altered night vision), grade 1-3 nausea/vomiting, and grade 1-2 diarrhea. The mean day 7 plasma fenretinide level was 2.90 +/- 1.66 μg/ml (7.40 +/- 4.25 muM; n = 14). The mean pre-treatment and day 7 plasma retinol levels were 0.47 +/- 0.16 μg/ml and 0.05 +/- 0.07 μg/ml (n = 8), respectively. The mean day 7 salivary fenretinide level was 0.08 +/- 0.18 μg/ml, with no correlation between salivary and plasma drug levels.. Fenretinide is well tolerated in patients with SCLC and stabilization of disease was noted in 24% of patients with this aggressive disease. However, after the first stage of enrollment, the response rate did not meet criteria to proceed with full trial accrual. Plasma concentrations of fenretinide that induce cytotoxicity in vitro in SCLC cell lines are clinically achievable, but there were no objective responses. Non-invasive drug monitoring using saliva underestimates systemic exposure.

Topics: Antineoplastic Agents; Dose-Response Relationship, Drug; Female; Fenretinide; Humans; Lung Neoplasms; Male; Middle Aged; Neoplasm Recurrence, Local; Small Cell Lung Carcinoma; Survival Analysis; Time Factors; Treatment Outcome; Vitamin A

Telomerase activation plays a critical role in tumorigenesis. To determine the role of telomerase in early lung carcinogenesis and as a potential biomarker in chemoprevention trials, we analyzed the expression of the human telomerase reverse transcriptase catalytic subunit (hTERT) in bronchial biopsy specimens from cigarette smokers who were enrolled in a randomized, double-blinded, placebo-controlled chemoprevention trial of N-(4-hydroxyphenyl)retinamide (4-HPR).. We obtained biopsy specimens from six predetermined sites in the bronchial tree from the 57 participants, before treatment and 6 months after treatment with 4-HPR or placebo. We used in situ hybridization to examine hTERT messenger RNA (mRNA) expression in 266 pretreatment (baseline) and post-treatment site-paired biopsy specimens from 27 patients in the 4-HPR-treated group and from 30 patients in the placebo-treated group. All statistical tests were two-sided.. At baseline, 62.4% (95% confidence interval [CI] = 53.9% to 71%) of the biopsy specimens obtained from the group treated with 4-HPR and 65.2% (95% CI = 57.4% to 73.1%) of the biopsy specimens obtained from the placebo-treated group expressed hTERT mRNA. After 6 months, 45.6% (95% CI = 36.9% to 54.3%) of the biopsy specimens obtained from the 4-HPR-treated group and 68.1% (95% CI = 60.4% to 75.8%) of the biopsy specimens obtained from the placebo-treated group expressed hTERT mRNA. The reduction in hTERT expression observed between the two treatment groups over time was statistically significant (P =.01) when we used the biopsy site as the unit of analysis, but not when we used the individual as the unit of analysis (P =.37).. Telomerase is frequently reactivated in the lungs of cigarette smokers. The modulation of hTERT expression in 4-HPR-treated smokers suggests that a novel molecular mechanism underlies the potential chemopreventive properties of 4-HPR. hTERT expression is a promising potential biomarker for risk assessment and for the evaluation of the efficacy of chemopreventive agents in lung carcinogenesis.

Topics: Adult; Aged; Anticarcinogenic Agents; Biomarkers, Tumor; Bronchi; Catalytic Domain; DNA-Binding Proteins; Double-Blind Method; Female; Fenretinide; Gene Expression Regulation, Enzymologic; Gene Expression Regulation, Neoplastic; Humans; Immunohistochemistry; In Situ Hybridization; Lung Neoplasms; Male; Middle Aged; Risk Assessment; RNA, Messenger; RNA, Neoplasm; Smoking; Telomerase; Treatment Outcome

Lung cancer remains the number one cause of cancer-related deaths in the United States. To reduce the mortality associated with this disease, individuals at risk must be identified prior to the development of lung cancer, and effective prevention strategies must be developed. One such strategy is to use retinoids like N-(4-hydroxyphenyl)retinamide (4-HPR), which has been found to possess chemopreventive activities in preclinical studies. In this study, 139 smokers were registered and 82 were randomized onto a double-blinded, placebo-controlled chemoprevention trial of 4-HPR administered p.o. (200 mg once daily). Of these, 70 participants were eligible for response evaluation. Biopsies were obtained at six predetermined sites in the bronchial tree from participants before and at the completion of 6 months of treatment. 4-HPR treatment had no measurable effect on histopathology (squamous metaplasia and dysplasia) in the bronchial epithelium of current smokers. 4-HPR was detected (104.5+/-64.0 ng/ml, mean +/- SD) in the serum of participants, supporting its potential bioavailability. Serum retinol levels decreased markedly (44% of placebo-treated patients) as a consequence of 4-HPR treatment. Notably, the mRNA level of retinoic acid receptor beta, which is typically increased by retinoid treatment, did not change in the bronchial epithelium of 4-HPR-treated participants. Clonal populations of bronchial epithelial cells were detected by analysis of loss of heterozygosity at putative tumor suppressor loci on chromosomes 3p, 9p, and 17p, and these changes were not altered by 4-HPR treatment. In conclusion, at this dose and schedule, 4-HPR was not effective in reversing squamous metaplasia, dysplasia, or genetic and phenotypic abnormalities in the bronchial epithelium of smokers.

Topics: Adult; Aged; Anticarcinogenic Agents; Biopsy; Bronchi; Bronchoscopy; Epithelium; Female; Fenretinide; Gene Expression; Humans; Lung Neoplasms; Male; Metaplasia; Middle Aged; Precancerous Conditions; Receptors, Retinoic Acid; Signal Transduction; Smoking

An increasing number of anticancer agents has been proposed in recent years with the attempt to overcome treatment-resistant cancer cells and particularly cancer stem cells (CSC), the major culprits for tumour resistance and recurrence. However, a huge obstacle to treatment success is the ineffective delivery of drugs within the tumour environment due to limited solubility, short circulation time or inconsistent stability of compounds that, together with concomitant dose-limiting systemic toxicity, contribute to hamper the achievement of therapeutic drug concentrations. The synthetic retinoid Fenretinide (4-hydroxy (phenyl)retinamide; 4-HPR) formerly emerged as a promising anticancer agent based on pre-clinical and clinical studies. However, a major limitation of fenretinide is traditionally represented by its poor aqueous solubility/bioavailability due to its hydrophobic nature, that undermined the clinical success of previous clinical trials.. Here, we developed a novel nano-micellar fenretinide formulation called bionanofenretinide (Bio-nFeR), based on drug encapsulation in an ion-pair stabilized lipid matrix, with the aim to raise fenretinide bioavailability and antitumour efficacy.. Bio-nFeR displayed marked antitumour activity against lung, colon and melanoma CSC both in vitro and in tumour xenografts, in absence of mice toxicity. Bio-nFeR is suitable for oral administration, reaching therapeutic concentrations within tumours and an unprecedented therapeutic activity in vivo as single agent.. Altogether, our results indicate Bio-nFeR as a novel anticancer agent with low toxicity and high activity against tumourigenic cells, potentially useful for the treatment of solid tumours of multiple origin.

Topics: Administration, Oral; Animals; Antineoplastic Agents; Apoptosis; Biological Availability; Cell Proliferation; Colonic Neoplasms; Female; Fenretinide; Humans; Lung Neoplasms; Melanoma; Mice; Mice, Inbred NOD; Mice, SCID; Micelles; Neoplastic Stem Cells; Tissue Distribution; Tumor Cells, Cultured; Xenograft Model Antitumor Assays

Fenretinide is a synthetic retinoid characterized by anticancer activity in preclinical models and favorable toxicological profile, but also by a low bioavailability that hindered its clinical efficacy in former clinical trials. We developed a new formulation of fenretinide complexed with 2-hydroxypropyl-beta-cyclodextrin (nanofenretinide) characterized by an increased bioavailability and therapeutic efficacy. Nanofenretinide was active in cell lines derived from multiple solid tumors, in primary spheroid cultures and in xenografts of lung and colorectal cancer, where it inhibited tumor growth independently from the mutational status of tumor cells. A global profiling of pathways activated by nanofenretinide was performed by reverse-phase proteomic arrays and lipid analysis, revealing widespread repression of the mTOR pathway, activation of apoptotic, autophagic and DNA damage signals and massive production of dihydroceramide, a bioactive lipid with pleiotropic effects on several biological processes. In cells that survived nanofenretinide treatment there was a decrease of factors involved in cell cycle progression and an increase in the levels of p16 and phosphorylated p38 MAPK with consequent block in G0 and early G1. The capacity of nanofenretinide to induce cancer cell death and quiescence, together with its elevated bioavailability and broad antitumor activity indicate its potential use in cancer treatment and chemoprevention.

Topics: Animals; Antineoplastic Agents; Apoptosis; Cell Cycle; Cell Line, Tumor; Cell Proliferation; Colonic Neoplasms; DNA Damage; Female; Fenretinide; Humans; Lung Neoplasms; Mice; p38 Mitogen-Activated Protein Kinases; Tumor Cells, Cultured; Xenograft Model Antitumor Assays

Sufficient knowledge regarding cellular and molecular basis of lung cancer progression and metastasis would help in the development of novel and effective strategies for the treatment of lung cancer. 4HPR is a synthetic retinoid with potential anti-tumor activity but is still limited because of its poor bioavailability. The use of albumin as a complexing agent for a hydrophobic drug is expected to improve the water solubility and consequently their bioavailability.This study investigated the antitumor activity of a novel complex between albumin and 4-HPR in a mouse model of human lung cancer and focuses on role and mechanism of Cav-1 mainly involved in regulating cancer and ACSVL3 mainly connected with tumor growth. Their expressions were assayed by immunohistochemistry and qRT-PCR, to demonstrate the reduction of the tumor growth following the drug treatment. Our results showed a high antitumor activity of 4HPR-HSA by reduction of the volume of tumor mass and the presence of a high level of apoptotic cell by TUNEL assay. The downregulation of Cav-1 and ACSVL3 suggested a reduction of tumor growth. In conclusion, we demonstrated the great potential of 4HPR-HSA in the treatment of lung cancer. More data about the mechanism of drug delivery the 4HPR-HSA are necessary.

Topics: Animals; Antineoplastic Agents; Apoptosis; Caveolin 1; Cell Line, Tumor; Coenzyme A Ligases; Female; Fenretinide; Gene Expression Regulation, Neoplastic; Humans; Immunohistochemistry; In Situ Nick-End Labeling; Lung Neoplasms; Mice, Nude; Reverse Transcriptase Polymerase Chain Reaction; Serum Albumin; Tumor Burden; Xenograft Model Antitumor Assays

To determine whether a polymer-drug conjugate might improve tumor cell kill compared to the corresponding unconjugated agent when used in combination with radiation, we examined the antitumor activity of a water-soluble conjugate of N-(4-hydroxyphenyl) retinamide (4HPR) and poly(L-glutamic acid), PG-4HPR, in lung cancer cells and xenografts. The antiproliferative activity of 4HPR and PG-4HPR in human lung cancer A549 cells was evaluated and the response of the cells to radiation measured by clonogenic assay. Response to irradiation was evaluated by measuring tumor growth delay in nude mice bearing intramuscularly inoculated A549 tumors. Histologic responses were assessed by examination of apoptosis (TUNEL assay) and cell proliferation (Ki67 staining). In vitro, 4HPR and PG-4HPR inhibited the proliferation of A549 cells, with IC50 values of 25.8 microM and >50 microM, respectively, after 24 h of continuous exposure and 6.25 microM and 9.75 microM, respectively, after 120 h. Both agents increased radiosensitivity at an equivalent 4HPR concentration of 10 microM after 5 days of exposure, with enhancement factors of 1.40 and 1.43. In tumor xenografts, intravenous injection of 4HPR or PG-4HPR (30 mg eq. 4HPR/kg) enhanced radiosensitivity by 1.3 and 1.6, respectively, without apparent systemic toxicity. PG-4HPR augmented radiation-induced apoptosis and decreased cellular proliferation in vivo. The radiation response of A549 tumors was greater with PG-4HPR than with 4HPR, which may be attributed to increased delivery of 4HPR to the tumors and enhanced apoptotic response. These results suggest that a polymeric delivery system may be useful for modulating radiosensitivity.

Topics: Anticarcinogenic Agents; Apoptosis; Cell Line, Tumor; Fenretinide; Humans; In Situ Nick-End Labeling; Lung Neoplasms; Polyglutamic Acid; Prodrugs

The growth inhibitory effects of four retinoic acid (RA) derivatives, 9-cis RA, 13-cis RA, N-(4-hydroxyphenyl) retinamide (4-HPR), and all-trans retinoic acid (ATRA) were compared. In addition, the effects of various combinations of these four agents were examined on non-small cell lung carcinoma (NSCLC) cell-lines, and on the expressions of retinoic acid receptors (RARs) and retinoid X receptors (RXRs) on these cells. At the clinically achievable concentration of 1 microM, only 4-HPR inhibited the growths of H1299 and H460 cells-lines. However, retinoic acid receptor beta(RAR beta) expression was up-regulated on H460 and H1299 cells treated with 1 microM of ATRA, 13-cis RA, or 9-cis RA. All NSCLC cell lines showed growth inhibition when exposed sequentially to 1 microM ATRA and 0.1 microM 4-HPR. In particular, sequential treatment with 1 microM ATRA or 13-cis RA and 4-HPR markedly inhibited H1703 cell growth; these cells exhibited no basal RAR beta expression and were refractory to 4-HPR. However, in NSCLC cell lines that expressed RAR beta, the expressional levels of RAR beta were up-regulated by ATRA alone and by sequential treatment with ATRA and 4-HPR. 4-HPR was found to be the most active of the four agents in terms of NSCLC growth-inhibition. Moreover, sequential treatments with ATRA or 13-cis RA followed by 4-HPR were found to have synergistic growth-inhibitory effects and to regulate RAR expression.

Topics: Alitretinoin; Base Sequence; Carcinoma, Non-Small-Cell Lung; Cell Line, Tumor; DNA Primers; Drug Therapy, Combination; Fenretinide; Gene Expression; Humans; Isotretinoin; Lung Neoplasms; Receptors, Retinoic Acid; Retinoid X Receptors; Tretinoin

Celecoxib is being evaluated as a chemopreventive agent. However, its mechanism of action is not clear because high doses were used for in vitro studies to obtain antitumor effects. We found that celecoxib inhibited the growth of premalignant and malignant human bronchial epithelial cells with IC(50) values between 8.9 and 32.7 micromol/L, irrespective of cyclooxygenase-2 (COX-2) expression. Normal human bronchial epithelial cells were less sensitive to celecoxib. Because these concentrations were higher than those attainable in vivo (

Topics: Anticarcinogenic Agents; Apoptosis; Bronchi; Bronchial Diseases; Celecoxib; Cell Line, Tumor; Cells, Cultured; Cyclooxygenase 2 Inhibitors; Drug Screening Assays, Antitumor; Drug Synergism; Epithelial Cells; Fenretinide; Humans; Lung Neoplasms; Mitochondria; Phosphorylation; Precancerous Conditions; Protein Processing, Post-Translational; Proto-Oncogene Proteins c-akt; Pyrazoles; Recombinant Fusion Proteins; Sulfonamides

Celecoxib exhibits cancer preventive and therapeutic effects in animal models and clinical trials. It presumably acts through selective inhibition of cyclooxygenase-2 (COX-2) and subsequent reduction of prostaglandin (PG) synthesis. However, the concentrations of celecoxib required for growth inhibition and apoptosis induction in vitro are higher than those needed for suppression of PGs. Moreover, those concentrations are not achievable in humans raising a controversy regarding the clinical relevance of in vitro data. We investigated the activity of celecoxib alone and in combination with the pro-apoptotic retinoid N-(4-hydroxyphenyl)retinamide (4HPR) on growth and apoptosis of human nonsmall cell lung cancer (NSCLC) cell lines. Celecoxib inhibited growth of thirteen NSCLC cell lines with IC50 values ranging from 19 to 33 microM regardless of their COX-2 expression. Apoptosis was induced in cells with high (A549) as well as low (H1792) COX-2 levels but only at a concentration of 75 microM celecoxib. However, treatment with pharmacologically feasible concentrations of celecoxib (< or = 10 microM) in combination with 4HPR (< or = 2 microM) resulted in a marked suppression of NSCLC cell growth and colony formation. Apoptosis mediated by activation of caspase-3, cleavage of PARP and lamin A was suppressed by addition of antioxidants, suggesting that the generation of reactive oxygen species was partially involved. This study indicates, that celecoxib combined with 4HPR is more effective than treatment with either agent alone in inhibition of growth and induction of apoptosis in NSCLC cells. It suggests further investigations of this combination for lung cancer treatment.

Topics: Antineoplastic Agents; Apoptosis; Carcinoma, Non-Small-Cell Lung; Caspase 3; Caspases; Celecoxib; Cell Line, Tumor; Cell Proliferation; Cyclooxygenase Inhibitors; Drug Synergism; Enzyme Activation; Fenretinide; Humans; Inhibitory Concentration 50; Lung Neoplasms; Pyrazoles; Sulfonamides

Topics: Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Celecoxib; Cyclooxygenase 2 Inhibitors; Fenretinide; Humans; Lung Neoplasms; Pyrazoles; Sulfonamides

N-(4-hydroxyphenyl) retinamide [4-HPR], a synthetic retinoid, has been shown to inhibit tumor cell growth, invasion, and metastasis by a mechanism that is not fully understood. Because the nuclear factor-kappaB (NF-kappaB) has also been shown to regulate proliferation, invasion, and metastasis of tumor cells, we postulated that 4-HPR modulates the activity of NF-kappaB. To test this postulate, we examined the effect of this retinoid on NF-kappaB and NF-kappaB-regulated gene products. We found that 4-HPR potentiated the apoptosis induced by tumor necrosis factor (TNF) and chemotherapeutic agents, suppressed TNF-induced invasion, and inhibited RANKL-induced osteoclastogenesis, all of which are known to require NF-kappaB activation. We found that 4-HPR suppressed both inducible and constitutive NF-kappaB activation without interfering with the direct DNA binding of NF-kappaB. 4-HPR was found to be synergistic with Velcade, a proteasome inhibitor. Further studies showed that 4-HPR blocked the phosphorylation and degradation of IkappaBalpha through the inhibition of activation of IkappaBalpha kinase (IKK), and this led to suppression of the phosphorylation and nuclear translocation of p65. 4-HPR also inhibited TNF-induced Akt activation linked with IKK activation. NF-kappaB-dependent reporter gene expression was also suppressed by 4-HPR, as was NF-kappaB reporter activity induced by TNFR1, TRADD, TRAF2, NIK, and IKK but not that induced by p65 transfection. The expression of NF-kappaB-regulated gene products involved in antiapoptosis (IAP1, Bfl-1/A1, Bcl-2, cFLIP, and TRAF1), proliferation (cyclin D1 and c-Myc), and angiogenesis (vascular endothelial growth factor, cyclooxygenase-2, and matrix metalloproteinase-9) were also down-regulated by 4-HPR. This correlated with potentiation of apoptosis induced by TNF and chemotherapeutic agents.

Topics: Antineoplastic Agents; Apoptosis; Boronic Acids; Bortezomib; Carcinoma, Small Cell; Carrier Proteins; Cell Growth Processes; Cyclin D1; Cyclooxygenase 2; Down-Regulation; Drug Synergism; Enzyme Activation; Fenretinide; Genes, myc; Humans; I-kappa B Kinase; I-kappa B Proteins; Lung Neoplasms; Membrane Glycoproteins; NF-kappa B; NF-KappaB Inhibitor alpha; Oncogene Protein v-akt; Osteoclasts; Phosphorylation; Promoter Regions, Genetic; Proto-Oncogene Proteins c-myc; Pyrazines; RANK Ligand; Receptor Activator of Nuclear Factor-kappa B; Transcription Factor RelA; Tumor Necrosis Factor-alpha; Vascular Endothelial Growth Factor A

Expression of retinoic acid receptor beta (RAR beta) and telomerase catalytic subunit (human telomerase reverse transcriptase [hTERT]) was analyzed in 285 bronchial biopsy specimens from 53 heavy cigarette smokers and four former smokers by using in situ hybridization. Of the 191 biopsy specimens that were positive for RAR beta, 69% expressed hTERT, whereas only 54% of the 94 RAR beta negative biopsy specimens expressed hTERT (P =.014). Because hTERT expression in bronchial tissue has been previously associated with increased risk of lung cancer, the association between RAR beta and hTERT expression suggests that RAR beta expression may be an indicator of increased risk of lung cancer in heavy smokers.

Topics: Adult; Aged; Anticarcinogenic Agents; Biomarkers, Tumor; Biopsy; Bronchi; Catalytic Domain; DNA-Binding Proteins; Female; Fenretinide; Gene Expression Regulation, Neoplastic; Humans; In Situ Hybridization; Lung Neoplasms; Male; Middle Aged; Randomized Controlled Trials as Topic; Receptors, Retinoic Acid; Respiratory Mucosa; Risk Factors; Smoking; Telomerase; Time Factors; Up-Regulation

The synthetic retinoid fenretinide [N-(4-hydroxyphenyl)retinamide, 4-HPR] has demonstrated growth inhibition and induction of apoptosis of various malignant cells, including lung cancer cell lines. 4-HPR is now being investigated in several clinical trials. In our study, we show that 4-HPR inhibits growth on a broad panel of lung cancer cell lines (12/12 small cell lung cancer and 9/12 nonsmall cell lung cancer cell lines), including cell lines unresponsive to all-trans-retinoic acid (ATRA). 4-HPR revealed a higher potency than ATRA in inhibiting cell growth with IC(50) values ranging from 3.3-8.5 microM. Furthermore, 4-HPR induces apoptosis in lung cancer cell lines as proven by TUNEL and annexin V assay. Despite this, we observed stimulation of growth in 2 SCLC cell lines at 1 microM 4-HPR. In advance to the clinical application of 4-HPR, we demonstrate that growth inhibition is reversible after removal of 4-HPR and that long-term application is necessary. Through long-term stimulation with 4-HPR, we cultivated 3 resistant cell lines that were still inhibited by 4-HPR after several weeks, however, exhibited almost no apoptosis. These cell lines exhibited morphologic changes, which in the case of the SCLC cell lines suggested differentiation. Our data show that 4-HPR inhibits growth in lung cancer cell lines by varying mechanisms including (i) cytostasis, (ii) apoptosis and (iii) presumably, differentiation. In contrast, the observed growth stimulation, reversibility of growth inhibition and development of resistance to apoptosis make successful cancer therapy uncertain and may limit clinical application of 4-HPR in lung cancer patients, although its inhibitory effects last over several weeks.

Topics: Antineoplastic Agents; Apoptosis; Carcinoma, Non-Small-Cell Lung; Carcinoma, Small Cell; Cell Differentiation; Cell Division; Cell Size; Dose-Response Relationship, Drug; Fenretinide; Flow Cytometry; Humans; In Situ Nick-End Labeling; Lung Neoplasms; Time Factors; Tretinoin; Tumor Cells, Cultured

Retinoids, the natural and synthetic derivatives of vitamin A, have been shown to regulate the growth and differentiation of a wide variety of cell types and consequently have enormous potential as chemotherapeutic agents. We have previously identified 2 genes, termed OVCA1 and OVCA2, which are located in a small region showing a high frequency of allelic loss in breast and ovarian tumors and share a common exon. Recent studies have suggested that expression of OVCA1 may be influenced by retinoids. Therefore, we analyzed the expression of OVCA1 and OVCA2 in cells in response to treatment with all-trans retinoic acid (RA) and N-(4-hydroxyphenyl)retinamide (4HPR), or under conditions of low serum and confluence, to determine further the roles of OVCA1 and OVCA2 in cell growth, apoptosis and differentiation. We show that OVCA2 mRNA and protein are ubiquitously expressed and that they are downregulated in the lung cancer cell line Calu-6 after treatment with RA and 4HPR. In addition, we observed that OVCA2 protein is proteolytically degraded in response to RA and 4HPR treatment in a time- and dose-dependent manner in the promyelocytic leukemia cell line HL60. In contrast, expression of the candidate tumor suppressor OVCA1 was not downregulated by these treatments. Furthermore, we demonstrate that OVCA2 is evolutionarily conserved and shows regional homology with dihydrofolate reductases (DHFRs), specifically with hydrolase folds found in alpha-beta hydrolases. Our results are in contrast to a previous report and show that OVCA2, not OVCA1 mRNA and protein, is downregulated in response to RA and 4HPR.

Topics: Amino Acid Sequence; Animals; Apoptosis; Cell Division; COS Cells; Down-Regulation; Evolution, Molecular; Fenretinide; Genes, Tumor Suppressor; HeLa Cells; Humans; Leukemia, Promyelocytic, Acute; Lung Neoplasms; Minor Histocompatibility Antigens; Models, Molecular; Molecular Sequence Data; Proteins; Retinoids; RNA, Messenger; Sequence Homology; Tissue Distribution; Tretinoin; Tumor Cells, Cultured; Tumor Suppressor Proteins

Topics: Carcinoma, Non-Small-Cell Lung; DNA-Binding Proteins; Fenretinide; Gene Expression Regulation, Enzymologic; Gene Expression Regulation, Neoplastic; Humans; Lung Neoplasms; Polymerase Chain Reaction; Respiratory Mucosa; Smoking; Telomerase

The synthetic retinoid, N-(4-hydroxyphenyl)retinamide (4HPR), which is currently being evaluated in clinical trials for cancer prevention and therapy, inhibits the growth of a variety of malignant cells through induction of apoptosis. However, in the majority of tumor cells, this inhibitory effect of 4HPR requires high concentrations (>1 microM), which exceed the peak plasma level measured in humans. In the present study, we compared and contrasted the effects of several synthetic retinamides on the growth of human lung and head and neck cancer cells in vitro. We found that some retinamides, especially N-(2-carboxyphenyl)retinamide (2CPR), exhibited better growth inhibitory effects than 4HPR in some of the cell lines. 2CPR exerted potent growth inhibitory effects in 5 of 10 head and neck cancer cell lines and in 1 of 10 lung cancer cell lines (IC(50), <0.8 microM). 2CPR (1 microM) induced apoptosis ranging from 10 to 60% in four of five cell lines, whereas 4HPR was ineffective at the same concentration. Unlike 4HPR, 2CPR (up to 10 microM) failed to induce reactive oxygen species production in these sensitive cell lines but could activate caspases 3 and 7 as well as increase poly(ADP-ribose)polymerase cleavage. Interestingly, the effect of 2CPR on cell growth could be suppressed by the specific retinoic acid receptor pan antagonist AGN193109. Our results suggest that 2CPR acts via retinoic acid receptors and may be a good candidate for prevention and treatment of some head and neck and lung cancers.

Topics: Anticarcinogenic Agents; Apoptosis; Carcinoma, Non-Small-Cell Lung; Fenretinide; Head and Neck Neoplasms; Humans; Lung Neoplasms; Reactive Oxygen Species; Receptors, Retinoic Acid; Retinoids; Tretinoin; Tumor Cells, Cultured

Fenretinide [N-(4-hydroxyphenyl)retinamide, 4HPR], a synthetic retinoid, is a potent inducer of apoptosis in small-cell lung cancer (SCLC) cell lines that may act through the generation of reactive oxygen species, suggesting that it may enhance the activity of other cytotoxic agents. In light of 4HPR's clinical potential and potent activity against SCLC cells, we evaluated the in vitro activity of 4HPR in combination with cisplatin, etoposide or paclitaxel.. The growth-inhibitory activities of single-agent 4HPR, cisplatin, etoposide or paclitaxel, and combinations of 4HPR and individual chemotherapeutic agents, were evaluated using an MTT assay in two SCLC cell lines. Each two-drug combination was studied over a range of concentrations at a fixed ratio corresponding to the ratio of the IC5 values of the individual agents. Data were analyzed by median-effect analysis as previously applied to drug combination studies.. All four agents inhibited growth in a dose-dependent manner in the NCI-H82 and NCI-H446 SCLC cell lines. At clinically reported drug concentrations that resulted in over 50% growth inhibition, the activities of the combinations 4HPR and cisplatin and 4HPR and etoposide were more than additive in both cell lines, and the activity of 4HPR plus paclitaxel was more than additive in NCI-H446 cells.. 4HPR's potent single-agent activity, minimal toxicity, and potential synergy with standard cytotoxic drugs will allow for the development of promising investigational regimens for the treatment of patients with SCLC.

Topics: Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Carcinoma, Small Cell; Cell Division; Cisplatin; Dose-Response Relationship, Drug; Drug Interactions; Etoposide; Fenretinide; Humans; Lung Neoplasms; Paclitaxel; Tumor Cells, Cultured

The induction of apoptosis by the synthetic retinoid N-(4-hydroxyphenyl)retinamide (4HPR) has been documented in vitro in various cancer types. A role for reactive oxygen species (ROS) in apoptosis induced by 4HPR in some cancer cells has been demonstrated recently. We studied five different human head and neck and five lung cancer cell lines to determine whether the ROS play a general role in 4HPR-induced apoptosis. We found that 4HPR induced apoptosis in all of the cell lines; however, this effect was blocked by antioxidants in only 2 of the 10 cell lines. 4HPR induced a greater than 4-fold increase in the generation of intracellular ROS in these two cell lines compared with a much lower effect in other cell lines. Furthermore, these two cell lines were most sensitive to the induction of apoptosis by 4HPR. The level of the cellular antioxidant thiol and superoxide dismutase activity were relatively lower in cells, which responded to 4HPR with a high level of ROS generation. These results indicate that although ROS can mediate 4HPR-induced apoptosis in some cells, which may have a low endogenous cellular antioxidant levels, other mechanisms exist for 4HPR-induced apoptosis. One such mechanism may involve retinoic acid receptors (RARs) because an RAR antagonist was able to block partially 4HPR-induced apoptosis. In conclusion, 4HPR-induced apoptosis involves at least three different mechanisms, which are complex and can overlap in the same cell line: (a) one mechanism involving 4HPR-induced ROS; (b) one involving RARs; and (c) at least one that does not involve ROS or RARs and remains unclear.

Topics: Antineoplastic Agents; Antioxidants; Apoptosis; Ascorbic Acid; Carcinoma, Non-Small-Cell Lung; Carcinoma, Squamous Cell; Fenretinide; Head and Neck Neoplasms; Humans; Lung Neoplasms; Naphthalenes; Neoplasm Proteins; Oxidation-Reduction; Oxidative Stress; Reactive Oxygen Species; Receptors, Retinoic Acid; Sulfhydryl Compounds; Superoxide Dismutase; Tumor Cells, Cultured

Four agents, fumaric acid (FA), N-acetylcysteine (NAC), N-(4-hydroxyphenyl) retinamide (4-HPR) and beta-carotene (beta-CT), were evaluated for potential chemopreventive activity using the tobacco-specific carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)-induced lung tumor model in female A/J mice. The agents were evaluated in both 16-week and 52-week bioassays at two dose levels corresponding to 0.8 maximum tolerated dose (MTD) and 0.4 MTD administered throughout the bioassay either in the diet (FA, 160 and 80 mmol/kg diet; NAC, 160 and 80 mmol/kg diet; 4-HPR, 4 and 2 mmol/kg diet) or by subcutaneous injection twice a week (beta-CT, 32 and 16 mg/kg b.w.). Mice were treated with a single i.p. dose of 10 micromol NNK in saline 1 week after administration of test agent. Lung adenomas were evaluated in the 16-week bioassay, whereas both adenomas and adenocarcinomas of the lung were determined in the 52-week bioassay. Both bioassays showed that all four agents did not significantly inhibit the total tumor incidence and multiplicity of the lung. However, the incidence of adenocarcinomas was reduced (P < 0.01) at 52 weeks in NNK groups given either 0.8 MTD NAC or 0.8 MTD beta-CT compared with the NNK control group. The decreases in adenocarcinomas were accompanied by corresponding increases in adenomas in these treatment groups. Thus, this study showed that FA, NAC, 4-HPR and beta-CT did not inhibit the total tumor formation, however, at the higher doses both NAC and beta-CT significantly retarded the malignant progression in the lung of NNK-treated A/J mice.

Topics: Acetylcysteine; Animals; Anticarcinogenic Agents; beta Carotene; Carcinogens; Dose-Response Relationship, Drug; Female; Fenretinide; Fumarates; Lung Neoplasms; Mice; Mice, Inbred A; Nicotiana; Nitrosamines; Plants, Toxic

Most human non-small cell lung cancer (NSCLC) cell lines are refractory to all-trans-retinoic acid (ATRA). Recently, N-(4-hydroxyphenyl)retinamide (4HPR) was found to induce apoptosis in various tumor cells. In this study, we compared and contrasted the effects of 4HPR and ATRA on the growth and apoptosis of 10 NSCLC cell lines and normal human bronchial epithelial (NHBE) cells. All of the cancer cell lines and the NHBE cells were sensitive to 10 microM 4HPR, and their numbers decreased to <20% of the controls after a 5-day treatment, whereas ATRA decreased cell numbers to about 50% of the controls in three cell lines and was less effective in the rest of the tumor cell lines. ATRA inhibited the growth of the NHBE cells by 70-80%. 4HPR induced apoptosis in most of the cells, including the ATRA-resistant ones, as evidenced by a DNA fragmentation assay. No correlation was found between growth inhibition by 4HPR and the expression of retinoic acid receptor beta (determined by Northern blotting and PCR), p53, or Bcl-2 proteins (analyzed by Western blotting). These results demonstrate that 4HPR is more potent than ATRA in inducing apoptosis in NSCLC cells and suggest that further clinical trials for prevention and therapy of NSCLC using 4HPR are warranted.

Topics: Antineoplastic Agents; Apoptosis; Carcinoma, Non-Small-Cell Lung; Carcinoma, Small Cell; Cell Cycle; Cell Division; Drug Screening Assays, Antitumor; Fenretinide; Genes, bcl-2; Humans; Lung Neoplasms; Receptors, Retinoic Acid; Tretinoin; Tumor Cells, Cultured; Tumor Suppressor Protein p53

In order to better understand the mechanisms that underlie the antiproliferative effect of retinoids, we have examined the response of human carcinoma cell lines to all-trans retinoic acid (RA) and N-(4-hydroxyphenyl) retinamide (4HPR) in terms of cell growth, apoptosis and regulation of retinoic acid receptors (RARs) and retinoid X receptors (RXRs) mRNA. GLC82 (lung adenocarcinoma), BGC823 (stomach adenocarcinoma) and EC109 (esophageal squamous carcinoma) cells were treated with 10 microM of RA or 4HPR for various length of time and analyzed. The results show that growth inhibition by RA and 4HPR in GLC82 and BGC823 cells correlates with the induction of RARbeta2 gene, whereas RA resistance in EC109 cells parallels loss of RARbeta2 induction. Exogenous RARbeta2 expression did not restore RA responsiveness in EC109 cells, but potentiated 4HPR-induced growth inhibition, suggesting that 4HPR acts at least in part via the RARbeta receptor. We speculate that the loss of RARbeta2 inducibility in EC109 cells may be due to an unknown repressor.

Topics: Adenocarcinoma; Antineoplastic Agents; Cell Division; Drug Resistance, Neoplasm; Esophageal Neoplasms; Fenretinide; Humans; Lung Neoplasms; Neoplasms; Receptors, Retinoic Acid; Retinoid X Receptors; Stomach Neoplasms; Transcription Factors; Transfection; Tretinoin; Tumor Cells, Cultured

Topics: Anticarcinogenic Agents; Antineoplastic Agents; Apoptosis; Carcinoma, Small Cell; Fenretinide; Humans; Lung Neoplasms; Neoplasms; Retinoids; Tumor Cells, Cultured

Lung cancer is the major cause of cancer-related death in the United States, with small-cell lung cancer (SCLC) constituting approximately 20% of all cases of lung cancer. Numerous epidemiologic and molecular studies have suggested that alterations in retinoid-signaling pathways play a role in the pathogenesis of lung cancer. Fenretinide [N-(4-hydroxyphenyl)retinamide; HPR] is a synthetic retinoid with minimal toxicity and favorable pharmacokinetics during long-term administration to patients in clinical trials.. The aim of this investigation was to study the effect of HPR on the growth of SCLC cells in vitro.. Seven SCLC cell lines (NCI-H69, NCI-H82, NCI-H146, NCI-H209, NCI-H345, NCI-H446, and NCI-H510A) were exposed continuously to a broad range of concentrations of HPR or all-trans-retinoic acid (RA), and cell viability was determined on day 3 and day 7 by the trypan blue dye exclusion assay. The growth of these cells was compared with that of control vehicle-treated cells to determine survival fraction and the dose resulting in a 50% inhibition of growth when compared with growth of control cells (IC50). The induction of apoptosis was evaluated by fluorescent microscopy, DNA content analysis, and a terminal deoxyribonucleotidyl transferase-based assay that labels 3'-hydroxyl ends of DNA fragments (TUNEL assay) combined with flow cytometric analysis.. HPR inhibited growth of a panel of SCLC cell lines at IC50 values that ranged from 0.1 to 3.0 microM (concentrations that are clinically achievable). In all cell lines tested, HPR was a more potent growth inhibitor than RA. By use of fluorescent microscopy, HPR was found to induce morphologic changes consistent with apoptosis in NCI-H82 SCLC cells, including cellular shrinkage, chromatin condensation, and nuclear fragmentation. Flow cytometric analysis revealed decreased DNA content, and TUNEL assay showed increased digoxigenin-uridine triphosphate incorporation in HPR-treated NCI-H82 SCLC cells; these findings are consistent with the induction of apoptosis.. HPR inhibited the in vitro growth of SCLC cells. In NCI-H82 cells, HPR inhibited growth via the induction of apoptosis.

Topics: Anticarcinogenic Agents; Antineoplastic Agents; Apoptosis; Carcinoma, Small Cell; Cell Survival; DNA, Neoplasm; Fenretinide; Flow Cytometry; Humans; Lung Neoplasms; Microscopy, Fluorescence; Tumor Cells, Cultured