sirolimus and Bone-Neoplasms

One of the great challenges of cancer medicine is to develop effective treatments for bone metastatic cancer. Most patients with advanced solid tumors will develop bone metastasis and will suffer from skeletal related events associated with this disease. Although some therapies are available to manage symptoms derived from bone metastases, an effective treatment has not been developed yet. The mammalian target of rapamycin (mTOR) pathway regulates cell growth and survival. Alterations in mTOR signaling have been associated with pathological malignancies, including bone metastatic cancer. Inhibition of mTOR signaling might therefore be a promising alternative for bone metastatic cancer management. This review summarizes the current knowledge on mTOR pathway signaling in bone tissue and provides an overview on the known effects of mTOR inhibition in bone cancer, both in in vitro and in vivo models.

Topics: Animals; Bone and Bones; Bone Neoplasms; Cell Proliferation; Humans; Mice; Molecular Targeted Therapy; Signal Transduction; Sirolimus; TOR Serine-Threonine Kinases

Skeletal metastases are an incurable complication afflicting the majority of patients who die from advanced breast cancer. They are most often osteolytic, characterized by net bone destruction and suppressed new bone formation. Life expectancy from first diagnosis of breast cancer bone metastases is several years, during which time skeletal-related events - including pain, fracture, hypercalcemia, and spinal cord compression - significantly degrade quality of life. The bone marrow niche can also confer hormonal and chemo-resistance. Most treatments for skeletal metastases target bone-destroying osteoclasts and are palliative. Recent results from the Breast cancer trials of Oral Everolimus-2 trial suggest that agents such as the mammalian target of rapamycin inhibitor everolimus may have efficacy against breast cancer bone metastases in part via stimulating osteoblasts as well as by inhibiting tumor growth. Selective estrogen receptor modulators similarly inhibit growth of estrogen receptor-positive breast cancers while having positive effects on the skeleton. This review discusses the future role of bone-anabolic agents for the specific treatment of osteolytic breast cancer metastases. Agents with both anti-tumor and bone-anabolic actions have been tested in the setting of multiple myeloma, a hematological malignancy that causes severe osteolytic bone loss and suppression of osteoblastic new bone formation. Stimulation of osteoblast activity inhibits multiple myeloma growth - a strategy that might decrease breast cancer burden in osteolytic bone metastases. Proteasome inhibitors (bortezomib and carfilzomib) inhibit the growth of myeloma directly and are anabolic for bone. Drugs with limited anti-tumor activity but which are anabolic for bone include intermittent parathyroid hormone and antibodies that neutralize the WNT inhibitors DKK1 and sclerostin, as well as the activin A blocker sotatercept and the osteoporosis drug strontium ranelate. Transforming growth factor-beta inhibitors have little tumor antiproliferative activity but block breast cancer production of osteolytic factors and are also anabolic for bone. Some of these treatments are already in clinical trials. This review provides an overview of agents with bone-anabolic properties, which may have utility in the treatment of breast cancer metastatic to the skeleton.

Topics: Antineoplastic Agents; Bone Density Conservation Agents; Bone Neoplasms; Boronic Acids; Bortezomib; Breast Neoplasms; Everolimus; Female; Humans; Oligopeptides; Osteoblasts; Parathyroid Hormone; Proteasome Inhibitors; Pyrazines; Recombinant Fusion Proteins; Sirolimus; Thiophenes; Transforming Growth Factor beta

Patients with breast cancer face substantial challenges to bone health from bone metastases, as well as from chemotherapy and endocrine therapies that generally elicit disease control at the cost of increased bone turnover. Consequently, maintaining bone health is of critical importance for these patients. Recently reported results from BOLERO-2 showed significant clinical benefits with adding everolimus to exemestane therapy in postmenopausal women with estrogen-receptor-positive breast cancer recurring or progressing despite nonsteroidal aromatase inhibitor therapy. Moreover, exploratory analyses from BOLERO-2 showed that adding everolimus may have beneficial effects on bone turnover and progressive disease in bone in this patient population. These results are supported by preclinical studies in which mTOR inhibition was associated with decreased osteoclast survival and activity. Thus, everolimus therapy may be able to ameliorate the negative effects of estrogen suppression on bone health. This review discusses the effects of mTOR inhibition on bone health during endocrine therapy.

Topics: Animals; Antineoplastic Agents; Bone and Bones; Bone Neoplasms; Breast Neoplasms; Everolimus; Female; Humans; Sirolimus; TOR Serine-Threonine Kinases

Patient outcomes remain poor for advanced or metastatic soft tissue sarcomas (STS) and bone sarcomas despite a growing number of clinical trials involving single- and multi-agent chemotherapy. mTOR is an intracellular kinase that plays a central role in regulating cell growth, metabolism, survival and proliferation. mTOR inhibitors including temsirolimus, everolimus and ridaforolimus have demonstrated broad anticancer activity. Ridaforolimus is a non-prodrug analog of rapamycin (sirolimus) with conserved affinity for mTOR but improved solubility, stability and bioavailability when compared with sirolimus. Early clinical trials reveal a reproducible and predictable pharmacokinetic profile, a potent, rapid and prolonged target inhibition and an acceptable safety and tolerability profile. Phase II and III trials of ridaforolimus have produced promising clinical activity against advanced sarcomas and will be presented.

Topics: Antineoplastic Agents; Bone Neoplasms; Clinical Trials as Topic; Humans; Neoplasm Invasiveness; Neoplasm Metastasis; Sarcoma; Sirolimus; Soft Tissue Neoplasms; TOR Serine-Threonine Kinases; Treatment Outcome

Despite the use of recommended chemotherapy regimens, patients with metastatic sarcomas have a poor prognosis. To date, the median overall survival for metastatic disease remains less than 18 months. First-line treatment of most metastatic sarcomas consists of chemotherapy with or without surgical excision of residual disease, followed by "watchful waiting" until disease progression or recurrence. According to the current treatment paradigm, recommended by United States and European clinical guidelines, chemotherapy is administered for a fixed number of cycles, and then a watchful waiting approach is taken once a best response is achieved. Single-agent doxorubicin remains the standard for treatment of most soft-tissue sarcomas (STS), as combination and dose-intense regimens have largely failed to improve survival. Combination chemotherapy is the standard treatment approach for osteosarcoma and Ewing's sarcoma, but outcomes are poor for patients with recurrent disease. In order to improve outcomes (in particular, progression-free survival [PFS] and overall survival [OS]), strategies shown to be effective in other solid malignancies, such as maintenance therapy and long-term treatment with targeted therapy, are being investigated in patients with advanced sarcomas. One potential promising approach is the use of mammalian target of rapamycin (mTOR) inhibitors for maintenance therapy. One such mTOR inhibitor, ridaforolimus (AP23573, MK-8669), is currently being evaluated in patients with advanced bone and STS in the ongoing Sarcoma mUlti-Center Clinical Evaluation of the Efficacy of riDaforolimus (SUCCEED) trial.

Topics: Antineoplastic Combined Chemotherapy Protocols; Bone Neoplasms; Carcinoma, Non-Small-Cell Lung; Disease-Free Survival; Doxorubicin; Female; Humans; Lung Neoplasms; Osteosarcoma; Ovarian Neoplasms; Sarcoma; Sarcoma, Ewing; Sirolimus; Soft Tissue Neoplasms; TOR Serine-Threonine Kinases

N-BP, rapamycin and its derivatives have been originally developed respectively as anti-resorptive and anti-fungal agents. In fact, in vitro and in vivo experiments demonstrated that these compounds are multi-functional molecules exerting their effects on tumour cell growth and bone remodelling. The major challenge in treating cancer relates to mutations in key genes such as p53, Rb or proteins affecting caspase signalling carried by many tumour cells. Whether nitrogen containing bisphosphonates (N-BP) are potent bone inhibitors, they also inhibit tumour cell proliferation and increase atypical apoptosis of bone tumour cells regardless of the p53 and Rb status. N-BP may be then considered as effective therapeutic agents in clinical trials of bone tumours. Rapamycin and its derivatives inhibit mTOR dependent mRNA translation both in osteoclasts and tumour cells. Cellular physiological mechanisms regulated by mTOR integrate many environmental parameters including growth factors, hormones, cytokines, amino acids, energy availability and cellular stresses that are coupled with cell cycle progression and cell growth. Rapamycin and its derivatives as well as N-BP must be considered as bi-(multi) functional molecules affecting simultaneously bone and tumour metabolisms. The present survey describes these two molecular families and discusses their therapeutic interests for primary bone tumours and bone metastases.

Topics: Bone Neoplasms; Cell Division; Diphosphates; Diphosphonates; Humans; Osteosarcoma; Protein Kinases; Sirolimus; Structure-Activity Relationship; TOR Serine-Threonine Kinases

Bone and soft tissue sarcomas represent rare tumors that can be cured by local treatment at early stages of disease. However, advanced or metastatic disease is rarely cured, and very few drugs have shown efficacy in this setting. Early studies with mTOR inhibitors have demonstrated antitumor activity in patients with metastatic sarcoma who failed previous chemotherapies. The response rate and durable stable disease in early studies, as well as the tolerability profile, recommend these drugs as promising candidates for further clinical studies. This article discusses preliminary results from clinical trials in patients with advanced or metastatic sarcoma as well as future perspectives.

Topics: Antineoplastic Agents; Bone Neoplasms; Drug Therapy, Combination; Everolimus; Gastrointestinal Stromal Tumors; Humans; Protein Kinase Inhibitors; Protein Kinases; Sarcoma; Sirolimus; Soft Tissue Neoplasms; TOR Serine-Threonine Kinases

The introduction of bisphosphonates represents an important advance in the care of patients with metastatic bone disease. Nonetheless, we remain unable to prevent metastatic bone destruction. This review will discuss several novel therapies, including inhibitors of receptor activator of nuclear factor-kappabeta, c-Src, mammalian target of rapamycin, cathepsin K, and alpha(5)beta(3) integrins, which could improve our control over this devastating complication.

Topics: Antineoplastic Agents; Bone Density Conservation Agents; Bone Neoplasms; Bone Remodeling; Breast Neoplasms; Cathepsin K; Cathepsins; Diphosphonates; Drugs, Investigational; Female; Humans; Integrin alpha Chains; Integrin beta Chains; Sirolimus

Primary osteosarcoma of the breast is a very rare malignancy that shares histological features with osteosarcoma. It is also highly sensitive to methionine restriction due to methionine addiction. We previously established a patient-derived orthotopic xenograft (PDOX) nude-mouse model derived from tumor tissue of a patient with primary mammary osteosarcoma. In the present study, we investigated the efficacy of oral-recombinant methioninase (o-rMETase), combined with rapamycin, an inhibitor of mammalian target of rapamycin (mTOR) kinase, on a mammary osteosarcoma PDOX nude-mouse model.. The PDOX mouse model was established by surgically transplanting a specimen of primary osteosarcoma of the breast into the mammary gland of nude mice. Mice implanted with tumors were randomly divided into four groups: Control group, N=5; rapamycin-treated group, N=5; o-rMETase-treated group, N=5; and a group treated with the combination of o-rMETase and rapamycin, N=5. Mice were treated for 2 weeks after transplantation, and tumor volume was measured during the treatment period.. Treatment with the combination of rapamycin and o-rMETase eradicated the osteosarcoma of the breast compared to the untreated control (p=0.000008). o-rMETase alone did not significantly inhibit tumor growth, and rapamycin alone only partially inhibited the tumor (p=0.78 and p=0.018, respectively) compared to the untreated control. There was not a significant difference in mouse weight between the groups.. The combination of rapamycin and o-rMETase was highly effective against primary osteosarcoma of the breast in a PDOX model, suggesting a future clinical strategy for this rare cancer type that currently has no first-line treatment.

Topics: Animals; Bone Neoplasms; Carbon-Sulfur Lyases; Disease Models, Animal; Heterografts; Methionine; Mice; Mice, Nude; Osteosarcoma; Recombinant Proteins; Sirolimus; TOR Serine-Threonine Kinases; Xenograft Model Antitumor Assays

The mTOR pathway has been identified as a key nutrient signaling hub that participates in metastatic progression of high-grade osteosarcoma. Inhibition of mTOR signaling is biologically achievable with sirolimus, and might slow the outgrowth of distant metastases. In this study, pet dogs with appendicular osteosarcoma were leveraged as high-value biologic models for pediatric osteosarcoma, to assess mTOR inhibition as a therapeutic strategy for attenuating metastatic disease progression.. A total of 324 pet dogs diagnosed with treatment-naïve appendicular osteosarcoma were randomized into a two-arm, multicenter, parallel superiority trial whereby dogs received amputation of the affected limb, followed by adjuvant carboplatin chemotherapy ± oral sirolimus therapy. The primary outcome measure was disease-free interval (DFI), as assessed by serial physical and radiologic detection of emergent macroscopic metastases; secondary outcomes included overall 1- and 2-year survival rates, and sirolimus pharmacokinetic variables and their correlative relationship to adverse events and clinical outcomes.. There was no significant difference in the median DFI or overall survival between the two arms of this trial; the median DFI and survival for standard-of-care (SOC; defined as amputation and carboplatin therapy) dogs was 180 days [95% confidence interval (CI), 144-237] and 282 days (95% CI, 224-383) and for SOC + sirolimus dogs, it was 204 days (95% CI, 157-217) and 280 days (95% CI, 252-332), respectively.. In a population of pet dogs nongenomically segmented for predicted mTOR inhibition response, sequentially administered adjuvant sirolimus, although well tolerated when added to a backbone of therapy, did not extend DFI or survival in dogs with appendicular osteosarcoma.

Topics: Amputation, Surgical; Animals; Bone Neoplasms; Carboplatin; Chemotherapy, Adjuvant; Combined Modality Therapy; Dog Diseases; Dogs; Osteosarcoma; Pets; Prospective Studies; Signal Transduction; Sirolimus; Survival Rate; TOR Serine-Threonine Kinases; Treatment Outcome

Patients with relapsed unresectable osteosarcoma represents an unmet need, so active and safe systemic treatments are required. Fas cell surface death receptor and mammalian target of rapamycin pathways are implicated in progressing osteosarcoma, and we had preclinical and clinical experience with a scheme that targets both pathways. Therefore, we designed a phase II trial with gemcitabine plus rapamycin, to determine the efficacy and safety, in this subset of patients.. A multicenter, single-arm phase II trial was sponsored by the Spanish Group for Research on Sarcoma. Osteosarcoma patients, relapsed or progressing after standard chemotherapy and unsuitable for metastasectomy received gemcitabine and rapamycin p.o. 5 mg/day except for the same day of gemcitabine administration, and the day before. The main end point was 4-month progression-free survival rate (PFSR), with the assumption that rates higher than 40% would be considered as an active regimen. Translational research aimed to correlate biomarkers with the clinical outcome.. Thirty-five patients were enrolled and received at least one cycle. PFSR at 4 months was 44%, and after central radiologic assessment, 2 partial responses and 14 stabilizations (48.5%) were reported from 33 assessable patients. The most frequent grade 3-4 adverse events were: neutropenia (37%), thrombocytopenia (20%), anemia (23%), and fatigue (15%); however, only three patients had febrile neutropenia. Positive protein expression of RRM1 significantly correlated with worse PFS and overall survival, while positivity of P-ERK1/2 was correlated with significant better overall survival.. Gemcitabine plus sirolimus exhibits satisfactory antitumor activity and safety in this osteosarcoma population, exceeding the prespecified 40% of 4-month PFSR. The significant correlation of biomarkers with clinical outcome encourages further prospective investigation.

Topics: Adolescent; Adult; Antineoplastic Combined Chemotherapy Protocols; Bone Neoplasms; Child; Child, Preschool; Deoxycytidine; Disease Progression; Disease-Free Survival; Female; Gemcitabine; Humans; Male; Middle Aged; Osteosarcoma; Recurrence; Sirolimus; Young Adult

Bone metastases from renal cell carcinoma (RCC) are a major cause of morbidity. Post hoc analysis has suggested that bone turnover markers can identify patients at risk of skeletal-related events (SREs) among those receiving zoledronic acid. This study sought to evaluate the effect on bone metastases of everolimus alone compared with everolimus plus zoledronic acid.. Thirty treatment-naive patients with RCC and ≥ 1 bone metastases were randomized 1:1 to everolimus (10 mg daily) versus everolimus plus zoledronic acid (4 mg intravenously 4-weekly). Bone-specific assessments were performed at baseline and at weeks 1, 4, 8, and 12. Treatment was continued on allocated arm until progression per RECIST 1.1 (Response Evaluation Criteria in Solid Tumors, version 1.1). The primary outcome measure was urine N-telopeptide (uNTX) level, with secondary measures of plasma C-telopeptide (CTX), quality of life (Functional Assessment of Cancer Therapy-Bone Pain [FACT-BP], Brief Pain Inventory [BPI]), progression-free survival (PFS), SREs, and safety.. After 12 weeks, reduction in mean uNTX and CTX on everolimus plus zoledronic acid relative to everolimus was 68.4% (95% CI, 60.1%-74.9%; P < .0001) and 76.2% (95% CI, 67.3%-82.7%; P < .0001), respectively. There was no evidence of a difference for FACT-BP (P = .5), but evidence was favorable for BPI Severity (P = .05) and BPI Interference (P = .06). Median PFS was 7.5 months (95% CI, 3.4-11.2) on everolimus plus zoledronic acid and 5.4 months (95% CI, 3.2-6.3) on everolimus (P = .009). Median time to first SRE was 9.6 months (95% CI, 4.3-15.5) on everolimus plus zoledronic acid and 5.2 months (95% CI, 1.6-8.2) on everolimus (P = .03).. In this RCC population, the addition of zoledronic acid to everolimus significantly reduced bone resorption markers and may prolong tumor control.

Topics: Aged; Antineoplastic Agents; Bone Density Conservation Agents; Bone Neoplasms; Carcinoma, Renal Cell; Collagen Type I; Diphosphonates; Everolimus; Female; Humans; Imidazoles; Kidney Neoplasms; Male; Middle Aged; Peptides; Prospective Studies; Sirolimus; Treatment Outcome; Zoledronic Acid

Results of previous study showed promising but short-lived activity of sorafenib in the treatment of patients with unresectable advanced and metastatic osteosarcoma. This treatment failure has been attributed to the mTOR pathway and might therefore be overcome with the addition of mTOR inhibitors. We aimed to investigate the activity of sorafenib in combination with everolimus in patients with inoperable high-grade osteosarcoma progressing after standard treatment.. We did this non-randomised phase 2 trial in three Italian Sarcoma Group centres. We enrolled adults (≥18 years) with relapsed or unresectable osteosarcoma progressing after standard treatment (methotrexate, cisplatin, and doxorubicin, with or without ifosfamide). Patients received 800 mg sorafenib plus 5 mg everolimus once a day until disease progression or unacceptable toxic effects. The primary endpoint was 6 month progression-free survival (PFS). All analyses were intention-to-treat. This trial is registered with ClinicalTrials.gov, number NCT01804374.. We enrolled 38 patients between June 16, 2011, and June 4, 2013. 17 (45%; 95% CI 28-61) of 38 patients were progression free at 6 months. Toxic effects led to dose reductions, or short interruptions, or both in 25 (66%) of 38 patients and permanent discontinuation for two (5%) patients. The most common grade 3-4 adverse events were lymphopenia and hypophosphataemia each in six (16%) patients, hand and foot syndrome in five (13%), thrombocytopenia in four (11%), and fatigue, oral mucositis, diarrhoea, and anaemia each in two (5%). One patient (3%) had a grade 3 pneumothorax that required trans-thoracic drainage, and that recurred at the time of disease progression. This was reported as a serious adverse event related to the study drugs in both instances. No other serious adverse events were reported during the trial. There were no treatment-related deaths.. Although the combination of sorafenib and everolimus showed activity as a further-line treatment for patients with advanced or unresectable osteosarcoma, it did not attain the prespecified target of 6 month PFS of 50% or greater.. Italian Sarcoma Group.

Topics: Adolescent; Adult; Antineoplastic Combined Chemotherapy Protocols; Bone Neoplasms; Disease Progression; Disease-Free Survival; Everolimus; Female; Humans; Intention to Treat Analysis; Italy; Kaplan-Meier Estimate; Male; Middle Aged; Neoplasm Grading; Niacinamide; Osteosarcoma; Phenylurea Compounds; Sirolimus; Sorafenib; Time Factors; TOR Serine-Threonine Kinases; Treatment Outcome; Young Adult

Breast Cancer Trials of Oral Everolimus 2 (BOLERO-2), a phase III study in postmenopausal women with estrogen receptor-positive breast cancer progressing despite nonsteroidal aromatase inhibitor therapy, showed statistically significant benefits with adding everolimus to exemestane. Moreover, in preclinical studies, mammalian target of rapamycin inhibition was associated with decreased osteoclast survival and activity. Exploratory analyses in BOLERO-2 evaluated the effect of everolimus on bone marker levels and progressive disease in bone.. Patients were treated with exemestane (25mg/day) and randomized (2:1) to everolimus (10mg/day; combination) or placebo (exemestane only). Exploratory endpoints included changes in bone turnover marker levels vs baseline and progressive disease in bone, defined as unequivocal progression of a preexisting bone lesion or the appearance of a new bone lesion.. Baseline disease characteristics were well balanced between arms (N = 724); baseline bisphosphonate use was not (43.9% combination vs 54.0% exemestane only). At a median of 18 months of follow-up, median progression-free survival (primary endpoint) was statistically significantly longer with the combination vs exemestane only (Cox proportional hazard ratio = 0.45, 95% confidence interval = 0.38 to 0.54; log-rank, 1-sided P < .0001). Bone marker levels at 6 and 12 weeks increased with exemestane only, as expected, but decreased with the combination. The cumulative incidence rate of progressive disease in bone was lower in the combination arm. Bone-related adverse events occurred with similar frequency in both arms (3.3% combination vs 4.2% exemestane only).. These exploratory analyses suggest that everolimus has beneficial effects on bone turnover and progressive disease in bone in patients receiving exemestane for hormone receptor-positive breast cancer progressing during/after nonsteroidal aromatase inhibitor therapy.

Topics: Aged; Alkaline Phosphatase; Androstadienes; Antineoplastic Agents; Aromatase Inhibitors; Bone Density; Bone Density Conservation Agents; Bone Neoplasms; Bone Remodeling; Bone Resorption; Breast Neoplasms; Collagen Type I; Confounding Factors, Epidemiologic; Disease Progression; Disease-Free Survival; Drug Administration Schedule; Everolimus; Female; Follow-Up Studies; Fractures, Spontaneous; Humans; Middle Aged; Odds Ratio; Osteogenesis; Postmenopause; Procollagen; Proportional Hazards Models; Receptors, Estrogen; Sirolimus; TOR Serine-Threonine Kinases; Treatment Failure; Treatment Outcome

Preclinical studies have shown synergistic antitumour activity by inhibition of insulin-like growth factor-1 receptor (IGF-1R) and mTOR. The expression of IGF-1R seems to be crucial for this effect. We investigated the safety and efficacy of the combination of the IGF-1R antibody cixutumumab and the mTOR inhibitor temsirolimus in patients with chemotherapy-refractory bone and soft-tissue sarcomas according to IGF-1R expression by immunohistochemistry.. We undertook a multicentre, open-label, phase 2 study in 19 cancer centres in the USA. Patients aged at least 16 years with a histologically confirmed diagnosis of bone or soft-tissue sarcoma were allocated on the basis of IGF-1R expression by immunohistochemistry to one of three treatment groups: IGF-1R-positive soft-tissue sarcoma (group A), IGF-1R-positive bone sarcomas (group B), or IGF-1R-negative bone and soft-tissue sarcoma (group C). Patients received weekly treatment with cixutumumab (6 mg/kg, intravenous) and temsirolimus (25 mg, intravenous flat dose) in 6-week cycles. A Simon optimal two-stage design was used for every arm. The primary endpoint was progression-free survival (PFS) at 12 weeks by intention-to-treat analysis in the first 54 patients assigned to every treatment arm. Although patients still remain on treatment, this trial has completed enrolment and this represents the final analysis. This study is registered with ClinicalTrials.gov, number NCT01016015.. Between Nov 18, 2009, and April 11, 2012, 388 patients were screened for IGF-1R expression and 54 were assigned to each arm. 17 of 54 patients in the IGF-1R-positive soft-tissue sarcoma group (31%; one-sided 95% CI lower bound 21%; two-sided 90% CI 21-43), 19 of 54 in IGF-1R-positive bone sarcoma group (35%; one-sided 95% CI lower bound 24%; two-sided 90% CI 24-47), and 21 of 54 in the IGF-1R-negative group (39%, one-sided 95% CI lower bound 28%; two-sided 90% CI 28-51) were progression free at 12 weeks. On April 6, 2011, the protocol was amended to include three additional patients in the IGF-1R-positive soft-tissue sarcoma group (total of 57 patients) and nine more in the IGF-1R-negative group (total of 63 patients). There were 2546 adverse events reported during the study, 214 (8%) of which were grade 3-4. The most common grade 3-4 toxicities in the 174 treated patients were anaemia in 16 (9%) patients, hyperglycaemia in 18 (10%), hypophosphataemia in 16 (9%), lymphopenia in 25 (14%), oral mucositis in 19 (11%), and thrombocytopenia in 19 (11%).. The combination of cixutumumab and temsirolimus shows clinical activity in patients with sarcoma and forms a basis for future trials. However, IGF-1R expression by immunohistochemistry is not predictive of clinical outcome after treatment with this combination.. National Cancer Institute and CycleforSurvival Fund, Memorial Sloan-Kettering Cancer Center.

Topics: Adult; Aged; Aged, 80 and over; Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Antineoplastic Combined Chemotherapy Protocols; Bone Neoplasms; Disease-Free Survival; Drug-Related Side Effects and Adverse Reactions; Female; Humans; Male; Middle Aged; Neoplasm Grading; Protein Kinase Inhibitors; Receptor, IGF Type 1; Sarcoma; Sirolimus; TOR Serine-Threonine Kinases

Phosphatase and tensin homologue (PTEN) loss is common in advanced prostate cancer, leading to constitutive activation of the PI3 kinase pathway. Temsirolimus blocks mammalian target of rapamycin (mTOR)/target of rapamycin complex 1 (TORC1), a key signaling node in this pathway; its activity in men with advanced castration-resistant metastatic prostate cancer (mCRPC) is unknown.. We conducted a single-arm trial of weekly intravenous temsirolimus administration in men with chemorefractory mCRPC who had ≥ 5 circulating tumor cells (CTCs) at baseline. The primary end point was the change in CTCs at 8 weeks; secondary end points were composite progression-free survival (PFS) (excluding prostate-specific antigen [PSA]), PSA and radiographic response rates, safety, and survival. At PSA/CTC progression, an anti-androgen could be added while continuing temsirolimus.. Eleven patients were accrued out of a planned 20; the trial was stopped prematurely because of lack of efficacy/feasibility. Median age was 61 years, with 55% African-Americans and 36% Caucasian patients. Median baseline PSA level was 390 ng/dL, median baseline number of CTCs was 14 cells; 50% of patients had pain, and 63% had undergone ≥ 2 previous chemotherapy regimens. Median CTC decline was 48% and 3 patients experienced decline in CTCs to < 5. However, 73% of men had a persistently unfavorable number of CTCs (≥ 5) and only 1 patient had a ≥ 30% PSA decline. Median PFS was 1.9 months (95% confidence interval [CI], 0.9-3.1) and median overall survival (OS) was 8.8 months (95% CI, 3.1-15.6). Toxicities included grade 4 hypophosphatemia and central nervous system (CNS) hemorrhage, and frequent grade 3 fatigue, anemia, stomatitis, hypokalemia, weakness, and hyperglycemia.. Temsirolimus lacked sufficient clinical activity in men with mCRPC, despite transient CTC improvements in some men. Future studies should focus on combination approaches or novel PI3K pathway inhibitors.

Topics: Adult; Aged; Bone Neoplasms; Disease Progression; Disease-Free Survival; Humans; Male; Mechanistic Target of Rapamycin Complex 1; Middle Aged; Multiprotein Complexes; Neoplastic Cells, Circulating; Phosphoinositide-3 Kinase Inhibitors; Prostate-Specific Antigen; Prostatic Neoplasms, Castration-Resistant; Protein Kinase Inhibitors; Sirolimus; Survival; TOR Serine-Threonine Kinases; Treatment Failure

This multicenter, phase II trial evaluated the efficacy and safety of everolimus, an mTOR inhibitor, in patients with metastatic or recurrent bone and soft-tissue sarcoma after the failure of anthracycline- and ifosfamide-containing regimens. Everolimus was administered orally as 10 mg once daily. The primary endpoint was the progression-free rate (PFR) at 16 weeks, assessed by computed tomography scan according to RECIST v1.0. Between July 2010 and May 2011, 41 patients were enrolled in this study. Among them, 83% received two or more regimens of chemotherapy prior to study entry. In 38 patients who the primary endpoint was evaluable, 11 patients reached 16 weeks progression-free (one with partial response and 10 with stable disease), indicating a PFR at 16 weeks of 27% (95% confidence interval [CI], 16-42%). The PFR at 16 weeks was highest in patients with angiosarcoma (2 of 3, 67%). With a median follow-up of 10.9 months (range, 2.3-23.9 months) in living patients, the median progression-free survival was 1.9 months (95% CI, 1.3-2.4 months) and the median overall survival was 5.8 months (95% CI, 3.6-8.0 months). Most adverse events were generally mild and tolerable. Grade 3/4 toxicities included hyperglycemia (15%), stomatitis (7%), pain (5%), and asthenia (5%). Everolimus shows modest antitumor activity with manageable toxicities in heavily pretreated patients with bone and soft-tissue sarcoma.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Anthracyclines; Antineoplastic Agents; Bone Neoplasms; Everolimus; Female; Humans; Ifosfamide; Male; Middle Aged; Sarcoma; Sirolimus; Soft Tissue Neoplasms; Tomography, X-Ray Computed; Treatment Outcome; Young Adult

Everolimus has shown to stop formation and activity of osteoclasts. Breast cancer patients with bone metastases only are candidates for effective but low toxic treatment.. We evaluated everolimus in a double-blind, placebo-controlled, phase II, randomized discontinuation study in breast cancer patients with HER2 negative breast cancer patients with bone metastases only. After being stable on 8 weeks of everolimus 10 mg/day, patients were randomized to everolimus-continuation or placebo. Primary outcome was time (from randomization) to progression (TTP). Seventy-six patients would have had to be randomized to show a hazard ration (HR) of 0.5 for everolimus-continuation.. Eighty-nine patients were enrolled in 4 years. Thirty-nine patients with SD after 8 weeks on everolimus were randomized to everolimus-continuation or placebo. TTP in patients with everolimus-continuation was 37.0 (95 % CI 16.7-40.3) versus 12.6 weeks (95 % CI 7.1-17.9) with placebo [HR 0.554 (95 % CI 0.282-1.09) p = 0.0818], adjusted for endocrine therapy [HR 0.464 (95 % CI 0.226-0.954) p = 0.037]. TTP in everolimus responders (n = 6) was 86 weeks.. The RADAR study is mainly hypothesis generating. It suggests that everolimus has single-agent activity, and patients with bone metastases only may retrieve long-term benefit from everolimus if they do not progress within 8 weeks of treatment.

Topics: Adult; Aged; Antineoplastic Agents; Bone Neoplasms; Breast Neoplasms; Disease Progression; Double-Blind Method; Drug-Related Side Effects and Adverse Reactions; Everolimus; Female; Humans; Middle Aged; Placebos; Sirolimus

Effective treatments for hormone-receptor-positive (HR(+)) breast cancer (BC) following relapse/progression on nonsteroidal aromatase inhibitor (NSAI) therapy are needed. Initial Breast Cancer Trials of OraL EveROlimus-2 (BOLERO-2) trial data demonstrated that everolimus and exemestane significantly prolonged progression-free survival (PFS) versus placebo plus exemestane alone in this patient population.. BOLERO-2 is a phase 3, double-blind, randomized, international trial comparing everolimus (10 mg/day) plus exemestane (25 mg/day) versus placebo plus exemestane in postmenopausal women with HR(+) advanced BC with recurrence/progression during or after NSAIs. The primary endpoint was PFS by local investigator review, and was confirmed by independent central radiology review. Overall survival, response rate, and clinical benefit rate were secondary endpoints.. Final study results with median 18-month follow-up show that median PFS remained significantly longer with everolimus plus exemestane versus placebo plus exemestane [investigator review: 7.8 versus 3.2 months, respectively; hazard ratio = 0.45 (95% confidence interval 0.38-0.54); log-rank P < 0.0001; central review: 11.0 versus 4.1 months, respectively; hazard ratio = 0.38 (95% confidence interval 0.31-0.48); log-rank P < 0.0001] in the overall population and in all prospectively defined subgroups, including patients with visceral metastases, [corrected] and irrespective of age. The incidence and severity of adverse events were consistent with those reported at the interim analysis and in other everolimus trials.. The addition of everolimus to exemestane markedly prolonged PFS in patients with HR(+) advanced BC with disease recurrence/progression following prior NSAIs. These results further support the use of everolimus plus exemestane in this patient population. ClinicalTrials.gov #NCT00863655.

Topics: Adult; Aged; Aged, 80 and over; Androstadienes; Antineoplastic Combined Chemotherapy Protocols; Bone Neoplasms; Breast Neoplasms; Disease-Free Survival; Double-Blind Method; Everolimus; Female; Humans; Liver Neoplasms; Lung Neoplasms; Middle Aged; Postmenopause; Receptors, Estrogen; Receptors, Progesterone; Sirolimus; Treatment Outcome

There are few effective therapies for high-risk sarcomas. Initial chemosensitivity is often followed by relapse. In vitro, mammalian target of rapamycin (mTOR) inhibition potentiates the efficacy of chemotherapy on resistant sarcoma cells. Although sarcoma trials using mTOR inhibitors have been disappointing, these drugs were used as maintenance. We conducted a Phase I/II clinical trial to test the ability of temsirolimus to potentiate the cytotoxic effect of liposomal doxorubicin and present here the dose-finding portion of this study. Adult and pediatric patients with recurrent or refractory sarcomas were treated with increasing doses of liposomal doxorubicin and temsirolimus using a continual reassessment method for escalation, targeting a dose-limiting toxicity rate of 20%. Blood samples were drawn before and after the first dose of temsirolimus in Cycles 1 and 2 for pharmacokinetic analysis. The maximally tolerated dose combination was liposomal doxorubicin 30 mg/m(2) monthly with temsirolimus 20 mg/m(2) weekly. Hematologic toxicity was common but manageable. Dose-limiting toxicities were primarily renal. Concurrent administration of liposomal doxorubicin resulted in increased exposure to sirolimus, the active metabolite of temsirolimus. Thus, the combination of liposomal doxorubicin and temsirolimus is safe for heavily pretreated sarcoma patients. Co-administration with liposomal doxorubicin did not alter temsirolimus pharmacokinetics, but increased exposure to its active metabolite.

Topics: Adolescent; Adult; Aged; Antineoplastic Agents; Bone Neoplasms; Child; Dose-Response Relationship, Drug; Doxorubicin; Female; Humans; Male; Middle Aged; Recurrence; Sarcoma; Sirolimus; Young Adult

Ridaforolimus is an inhibitor of mammalian target of rapamycin, an integral component of the phosphatidyl 3-kinase/AKT signaling pathway, with early evidence of activity in sarcomas. This multicenter, open-label, single-arm, phase II trial was conducted to assess the antitumor activity of ridaforolimus in patients with distinct subtypes of advanced sarcomas.. Patients with metastatic or unresectable soft tissue or bone sarcomas received ridaforolimus 12.5 mg administered as a 30-minute intravenous infusion once daily for 5 days every 2 weeks. The primary end point was clinical benefit response (CBR) rate (complete response or partial response [PR] or stable disease ≥ 16 weeks). Safety, progression-free survival (PFS), overall survival (OS), time to progression, and duration of response were also evaluated.. A total of 212 patients were treated in four separate histologic cohorts. In this heavily pretreated population, 61 patients (28.8%) achieved CBR. Median PFS was 15.3 weeks; median OS was 40 weeks. Response Evaluation Criteria in Solid Tumors (RECIST) confirmed response rate was 1.9%, with four patients achieving confirmed PR (two with osteosarcoma, one with spindle cell sarcoma, and one with malignant fibrous histiocytoma). Archival tumor protein markers analyzed were not correlated with CBR. Related adverse events were generally mild or moderate and consisted primarily of stomatitis, mucosal inflammation, mouth ulceration, rash, and fatigue.. Single-agent ridaforolimus in patients with advanced and pretreated sarcomas led to PFS results that compare favorably with historical metrics. A phase III trial based on these data will further define ridaforolimus activity in sarcomas.

Topics: Adult; Aged; Antineoplastic Agents; Biomarkers, Tumor; Bone Neoplasms; Disease-Free Survival; Drug Administration Schedule; Female; Humans; Infusions, Intravenous; Kaplan-Meier Estimate; Male; Middle Aged; Sarcoma; Sex Factors; Sirolimus; TOR Serine-Threonine Kinases; Treatment Outcome; Vascular Endothelial Growth Factor A

Resistance to endocrine therapy in breast cancer is associated with activation of the mammalian target of rapamycin (mTOR) intracellular signaling pathway. In early studies, the mTOR inhibitor everolimus added to endocrine therapy showed antitumor activity.. In this phase 3, randomized trial, we compared everolimus and exemestane versus exemestane and placebo (randomly assigned in a 2:1 ratio) in 724 patients with hormone-receptor-positive advanced breast cancer who had recurrence or progression while receiving previous therapy with a nonsteroidal aromatase inhibitor in the adjuvant setting or to treat advanced disease (or both). The primary end point was progression-free survival. Secondary end points included survival, response rate, and safety. A preplanned interim analysis was performed by an independent data and safety monitoring committee after 359 progression-free survival events were observed.. Baseline characteristics were well balanced between the two study groups. The median age was 62 years, 56% had visceral involvement, and 84% had hormone-sensitive disease. Previous therapy included letrozole or anastrozole (100%), tamoxifen (48%), fulvestrant (16%), and chemotherapy (68%). The most common grade 3 or 4 adverse events were stomatitis (8% in the everolimus-plus-exemestane group vs. 1% in the placebo-plus-exemestane group), anemia (6% vs. <1%), dyspnea (4% vs. 1%), hyperglycemia (4% vs. <1%), fatigue (4% vs. 1%), and pneumonitis (3% vs. 0%). At the interim analysis, median progression-free survival was 6.9 months with everolimus plus exemestane and 2.8 months with placebo plus exemestane, according to assessments by local investigators (hazard ratio for progression or death, 0.43; 95% confidence interval [CI], 0.35 to 0.54; P<0.001). Median progression-free survival was 10.6 months and 4.1 months, respectively, according to central assessment (hazard ratio, 0.36; 95% CI, 0.27 to 0.47; P<0.001).. Everolimus combined with an aromatase inhibitor improved progression-free survival in patients with hormone-receptor-positive advanced breast cancer previously treated with nonsteroidal aromatase inhibitors. (Funded by Novartis; BOLERO-2 ClinicalTrials.gov number, NCT00863655.).

Topics: Adult; Aged; Aged, 80 and over; Androstadienes; Antineoplastic Combined Chemotherapy Protocols; Aromatase Inhibitors; Bone Neoplasms; Breast Neoplasms; Disease-Free Survival; ErbB Receptors; Everolimus; Female; Humans; Kaplan-Meier Estimate; Middle Aged; Postmenopause; Recurrence; Sirolimus; Stomatitis; TOR Serine-Threonine Kinases

Temsirolimus was combined with cixutumumab, a fully human IgG1 monoclonal antibody directed at the insulin growth factor-1 receptor (IGF-1R).. Patients received cixutumumab, 6 mg/kg i.v. weekly, and temsirolimus, 25 to 37.5 mg i.v. weekly (4-week cycles), with restaging after 8 weeks. Median follow-up was 8.9 months.. Twenty patients [17 with Ewing's sarcoma (EWS), 3 with desmoplastic small-round cell tumor (DSRCT)] were enrolled. Twelve patients (60%) were men with a median age of 24 years and six median prior systemic therapies in a metastatic setting. The most frequent toxicities were thrombocytopenia (85%), mucositis (80%), hypercholesterolemia (75%), hypertriglyceridemia (70%), and hyperglycemia (65%; mostly grade I-II). Seven of 20 patients (35%) achieved stable disease (SD) for more than 5 months or complete/partial (CR/PR) responses. Tumor regression of more than 20% (23%, 23%, 27%, 100%, 100%) occurred in five of 17 (29%) patients with EWS, and they remained on study for 8 to 27 months. One of six patients with EWS who previously developed resistance to a different IGF-1R inhibitor antibody achieved a CR. Four of the seven best responders developed grade III mucositis, myelosuppression, or hyperglycemia, which were controlled while maintaining drug dose.. Cixutumumab combined with temsirolimus was well-tolerated and showed preliminary evidence of durable antitumor activity in heavily pretreated EWS family tumors.

Topics: Adolescent; Adult; Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Antineoplastic Combined Chemotherapy Protocols; Bone Neoplasms; Cohort Studies; Desmoplastic Small Round Cell Tumor; Female; Humans; Male; Neoplasm Grading; Prognosis; Receptor, IGF Type 1; Remission Induction; Sarcoma, Ewing; Sirolimus; TOR Serine-Threonine Kinases; Young Adult

In this study, two doses of temsirolimus (CCI-779), a novel inhibitor of the mammalian target of rapamycin, were evaluated for efficacy, safety, and pharmacokinetics in patients with locally advanced or metastatic breast cancer who had been heavily pretreated.. Patients (n = 109) were randomly assigned to receive 75 or 250 mg of temsirolimus weekly as a 30-minute intravenous infusion. Patients were evaluated for tumor response, time to tumor progression, adverse events, and pharmacokinetics of temsirolimus.. Temsirolimus produced an objective response rate of 9.2% (10 partial responses) in the intent-to-treat population. Median time to tumor progression was 12.0 weeks. Efficacy was similar for both dose levels but toxicity was more common with the higher dose level, especially grade 3 or 4 depression (10% of patients at the 250-mg dose level, 0% at the 75-mg dose level). The most common temsirolimus-related adverse events of all grades were mucositis (70%), maculopapular rash (51%), and nausea (43%). The most common, clinically important grade 3 or 4 adverse events were mucositis (9%), leukopenia (7%), hyperglycemia (7%), somnolence (6%), thrombocytopenia (5%), and depression (5%).. In heavily pretreated patients with locally advanced or metastatic breast cancer, 75 and 250 mg temsirolimus showed antitumor activity and 75 mg temsirolimus showed a generally tolerable safety profile.

Topics: Adult; Aged; Antineoplastic Agents; Area Under Curve; Bone Neoplasms; Breast Neoplasms; Female; Humans; Male; Middle Aged; Protein Kinase Inhibitors; Protein Kinases; Safety; Salvage Therapy; Sirolimus; Soft Tissue Neoplasms; TOR Serine-Threonine Kinases; Treatment Outcome

Osteosarcoma, derived from primitive mesenchymal cells, is the most common primary solid malignant tumor of bone. The cause of osteosarcoma remains unclear. In recent years, the role of non-coding sequences in regulating protein expression in tumors has been paid more and more attention, especially long non-coding RNA (lncRNA). We speculate that SRY-box transcription factor 21 antisense divergent transcript 1 (SOX21-AS1) can regulate the expression of the mechanistic target of rapamycin kinase (mTOR) and Kruppel-like factor 4 (KLF4) through sponging hsa-mir-7-5p and hsa-mir-145-5p. We knocked lncRNA SOX21-AS1 into the genome of 143B cells through CRISPR/Cas9, then screened out a monoclonal cell line. Detect the transcription level and protein expression level of the above-mentioned related genes, and cell proliferation. Then, ginsenoside Rg3 was added to culture the cell line knocked into lncRNA SOX21-AS1, and the expression levels of lncRNA SOX21-AS1, hsa-mir-7-5p, hsa-mir-145-5p, mTOR, and KLF4 were detected by RT-qPCR and Western blot. Cell proliferation method detects cell viability, explores the molecular mechanism of lncRNA SOX21-AS1 in osteosarcoma, and checks whether it can be used as a potential drug target for the treatment of osteosarcoma. Our results demonstrate that the overexpression of lncRNA SOX21-AS1 up-regulates mTOR and KLF4 by sponging hsa-mir-7-5p and hsa-mir-145-5p, and ultimately regulates the proliferation of osteosarcoma. It is proved that ginsenoside Rg3 can inhibit the cell proliferation of osteosarcoma by reducing the expression level of lncRNA SOX21-AS1. It provides an alternative for the treatment of osteosarcoma in the future.

Topics: Bone Neoplasms; Cell Line, Tumor; Cell Proliferation; CRISPR-Cas Systems; Humans; Kruppel-Like Factor 4; MicroRNAs; Osteosarcoma; RNA, Long Noncoding; Sirolimus; TOR Serine-Threonine Kinases

Activation of the mTOR pathway has been observed in osteosarcoma, however the inhibition of mammalian target of rapamycin (mTOR) complex 1 has had limited results in osteosarcoma treatment. Certain metabolic pathways can be altered by mTOR activation, which can affect survival. Our aim was to characterize the mTOR profile and certain metabolic alterations in pediatric osteosarcoma to determine the interactions between the mTOR pathway and metabolic pathways. We performed immunohistochemistry on 28 samples to analyze the expression of mTOR complexes such as phospho-mTOR (pmTOR), phosphorylated ribosomal S6 (pS6), and rapamycin-insensitive companion of mTOR (rictor). To characterize metabolic pathway markers, we investigated the expression of phosphofructokinase (PFK), lactate dehydrogenase-A (LDHA), β-F1-ATPase (ATPB), glucose-6-phosphate dehydrogenase (G6PDH), glutaminase (GLS), fatty acid synthetase (FASN), and carnitin-O-palmitoyltransferase-1 (CPT1A). In total, 61% of the cases showed low mTOR activity, but higher pmTOR expression was associated with poor histological response to chemotherapy and osteoblastic subtype. Rictor expression was higher in metastatic disease and older age at the time of diagnosis. Our findings suggest the importance of the Warburg-effect, pentose-phosphate pathway, glutamine demand, and fatty-acid beta oxidation in osteosarcoma cells. mTOR activation is linked to several metabolic pathways. We suggest performing a detailed investigation of the mTOR profile before considering mTORC1 inhibitor therapy. Our findings highlight that targeting certain metabolic pathways could be an alternative therapeutic approach.

Topics: Bone Neoplasms; Child; Humans; Mechanistic Target of Rapamycin Complex 1; Mechanistic Target of Rapamycin Complex 2; Osteosarcoma; Sirolimus; TOR Serine-Threonine Kinases

Licochalcone B (LicB) is a flavonoid derived from the Chinese medicinal herb Glycyrrhiza uralensis Fisch. Several previous studies have demonstrated the wide range of pharmacological activities shown by LicB. In this study, we investigated the anticancer effects of LicB in osteosarcoma (OS) tumor cells and its underlying mechanisms. According to the Cell Counting Kit-8 (CCK8) analysis and 5-ethynil-2'-deoxyuridine (EdU) staining results, we found that LicB suppresses OS cells (MG-63 and U2OS) growth depending on its concentration. Furthermore, flow cytometry and Western blot revealed that LicB promoted autophagy and apoptosis in OS cells in a dose-dependent manner. LicB treatment not only decreased the levels of Bcl-2, p62, Caspase-3, and Ki67 protein in MG-63 and U2OS cell lines but also increased the levels of Cleaved Caspase-3, Beclin1, Bax, Atg7, and LC3B. Mechanistically, LicB induced cell apoptosis by promoting the apoptosis-related cleavage of Caspase-3, while suppressing the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway to induce autophagy. The present work is the first to illustrate that LicB can serve as a potential drug candidate for tumor treatment owing to its ability to enhance autophagy and apoptosis, and suppress OS proliferation by inactivating the PI3K/AKT/mTOR pathway.

Topics: Apoptosis; Autophagy; Bone Neoplasms; Caspase 3; Cell Line, Tumor; Cell Proliferation; Chalcones; Humans; Osteosarcoma; Phosphatidylinositol 3-Kinase; Phosphatidylinositol 3-Kinases; Proto-Oncogene Proteins c-akt; Signal Transduction; Sirolimus; TOR Serine-Threonine Kinases

Biglycan is a class I secreted small leucine-rich proteoglycan (SLRP), which regulates signaling pathways connected to bone pathologies. Autophagy is a vital catabolic process with a dual role in cancer progression. Here, we show that biglycan inhibits autophagy in two osteosarcoma cell lines (

Topics: Autophagy; beta Catenin; Bone Neoplasms; Cell Line, Tumor; Cell Proliferation; Doxorubicin; Humans; Osteosarcoma; Sirolimus; Wnt Signaling Pathway

Osteosarcoma (OS) is a malignant bone neoplasm, mostly occurring in pediatric patients. OS is characterized by a highly aggressive and metastatically active tumor. Chemotherapy followed by surgical excision is the treatment of choice but is often associated with both chemoresistance and relapse. Hence, it is important to develop further understanding of OS pathogenesis and identify potential therapeutic targets. Both the signal transducer and activator of transcription 3 (STAT3) and mammalian target of rapamycin (mTOR) have been implicated in OS pathogenesis. Crosstalk between mTOR and STAT3 signaling has been shown to regulate hypoxia-induced angiogenesis in other diseases. In this study, we determined using OS cell lines if there is a crosstalk between these two pathways and how that impacts sensitivity to treatment with Rapamycin. OS cell lines exhibited differential sensitivity to mTOR inhibitor Rapamycin. Evaluation of phosphorylated STAT3 showed that in Rapamycin-sensitive 143B cells, the inhibitor decreased phosphorylation of STAT3 at Y705, but not at S727 whereas, in Rapamycin-resistant U2OS cells, the inhibitor decreased S727 phosphorylation but not Y705. However, knockdown of STAT3 in U2OS cells made them sensitive to Rapamycin. Immunofluorescence (IF) analysis showed that mTOR is constitutively activated in the 143B cells but is suppressed in the U2OS cells, indicating that this might be their reason for being resistant to Rapamycin. Both cell lines were sensitive to treatment with the STAT3 inhibitor Napabucasin (NP). Treatment with NP inhibited STAT3 activation at Y705 and additionally inhibited mTOR activation, indicating crosstalk between STAT3 and mTOR signaling pathways. Rapamycin could effectively prevent lung metastasis in an orthotropic OS mice model using 143B cells. However, Rapamycin could not inhibit lung metastasis in mice injected with U2OS cells. The STAT3 inhibitor NP attenuated lung metastasis with the U2OS cells. Our results thus established yet undefined crosstalk of STAT3 and mTOR signaling pathways in OS and highlight the possibility of using mTOR inhibitors for treatment in patients with OS.

Topics: Animals; Antibiotics, Antineoplastic; Benzofurans; Bone Neoplasms; Cell Line, Tumor; Drug Resistance, Neoplasm; Female; Humans; Mice, Inbred BALB C; Naphthoquinones; Osteosarcoma; Phosphorylation; Signal Transduction; Sirolimus; STAT3 Transcription Factor; TOR Serine-Threonine Kinases; Xenograft Model Antitumor Assays

We previously showed that the use of autophagy inhibitors in combination with chemotherapy can enhance anticancer effects in sarcoma cell lines. In this study, we investigated the combined effect of the autophagy inhibitor chloroquine and the mTOR inhibitor rapamycin on MG63 osteosarcoma cells.. Effects of chloroquine and/or rapamycin on cell proliferation were assessed by WST-1 assays. Effects of chloroquine and/or rapamycin on the mTOR pathway components, autophagy, and apoptosis were investigated by western blot, flow cytometry, and fluorescence microscopy using immunocytochemical staining of LC3 and Annexin V-FITC/propidium iodide.. Rapamycin suppressed cell growth and inhibited the mTOR pathway. Rapamycin promoted autophagy by blocking the mTOR pathway, and chloroquine enhanced apoptosis by blocking autophagy.. Chloroquine enhances the effects of rapamycin in inducing apoptosis via autophagy inhibition in MG63 cells. Thus, the combined therapy of chloroquine and rapamycin may be a potent treatment for osteosarcoma.

Topics: Antibiotics, Antineoplastic; Apoptosis; Autophagy; Bone Neoplasms; Cell Line, Tumor; Cell Proliferation; Chloroquine; Dose-Response Relationship, Drug; Drug Synergism; Humans; Microscopy, Fluorescence; Osteosarcoma; Sirolimus; TOR Serine-Threonine Kinases

Pseudomyogenic hemangioendothelioma (PMH) is a rare neoplasm with vascular and sarcomatous elements, unpredictable course, and uncommon metastatic or fatal potential. Although systemic chemotherapy has been reported with variable success, generally accepted treatment is aggressive surgery with wide margins. Evidence-based treatment options are lacking, and lack of clear prognostic features poses a risk of undertreatment or overtreatment with associated morbidity and mortality. We report the use of initial systemic therapy with oral sirolimus (SIR) and IV zoledronic acid (ZA) to induce a sustained clinical response and avoidance of amputation in a 6-year-old boy. At 37 months after diagnosis, our patient remains in sustained clinical remission as documented by x-ray, MRI, and PET-CT with return of normal mobility/activity and resolution of swelling and pain. Literature review identified 20 cases of pediatric and young adult patients with PMH, of which 7 received some form of systemic therapy. To the best of our knowledge, our patient represents the youngest reported case of PMH and the first successful and limb-sparing utilization of systemic chemotherapy as primary treatment for PMH.

Topics: Bone Neoplasms; Child; Hemangioendothelioma; Humans; Male; Multimodal Imaging; Sirolimus; Zoledronic Acid

The mammalian target of rapamycin inhibitor everolimus is approved as an antitumor agent in advanced estrogen receptor-positive breast cancer. Surrogate bone marker data from clinical trials suggest effects on bone metabolism, but the mode of action of everolimus in bone biology remains unclear. In this study, we assessed potential bone-protective effects of everolimus in the context of osteotropic tumors.. The effects of everolimus on cancer cell viability in vitro and on tumor growth in vivo were assessed. Everolimus-regulated osteoclastogenesis and osteoblastogenesis were also assessed in vitro before we assessed the bone-protective effect of everolimus in a model where bone loss was induced in ovariectomized (OVX) mice. Finally, the role of everolimus in the progression of osteolytic bone disease was assessed in an intracardiac model of breast cancer bone metastases.. At low concentrations (1 nM) in vitro, everolimus reduced the viability of human and murine cancer cell lines and impaired the osteoclastogenesis of osteoclast progenitors as assessed by quantitative real-time polymerase chain reaction and counting tartrate-resistant acid phosphatase-positive, multinucleated osteoclasts (p < 0.001). Everolimus had little or no deleterious effect on osteoblastogenesis in vitro, with concentrations of 1 and 10 nM increasing the messenger RNA expression of osteoblast marker genes (p ≤ 0.05) and leaving mineralization in differentiated human mesenchymal stem cells unchanged. Everolimus treatment (1 mg/kg body weight/day) prevented the bone loss observed in OVX mice and concurrently inhibited the metastatic growth of MDA-MB-231 cells by 70% (p < 0.002) while preserving bone mass in an intracardiac model of bone metastasis.. These results underline the antitumor effects of everolimus and highlight its bone-protective efficacy, warranting further research on the potential implications on bone health in populations prone to osteoporosis and bone metastases, such as postmenopausal women with breast cancer.

Topics: Animals; Bone Neoplasms; Breast Neoplasms; Cell Differentiation; Cell Line, Tumor; Cell Survival; Everolimus; Female; Humans; Mice; Osteoblasts; Osteoporosis; RAW 264.7 Cells; Sirolimus

mTOR pathway inhibitors are important drugs for the treatment of advanced renal cell carcinoma (RCC). However, no valid predictive markers have been identified to guide treatment selection and identify patients who are sensitive to these drugs. Mutations activating the mTOR pathway have been suggested to predict response; however, their predictive value is still unclear. Here, we present the genomic and functional characterization of a patient with metastatic clear cell RCC (ccRCC) who experienced a partial response to temsirolimus after a poor response to 2 previous lines of treatment. At the time of publication, the patient was disease-free 8 years after temsirolimus treatment. Multiregion whole-exome sequencing (WES) on 3 regions of the primary tumor, 1 metastasis, and blood revealed tumor mutations in driver genes in ccRCC: a missense mutation in

Topics: Antineoplastic Combined Chemotherapy Protocols; Biomarkers, Tumor; Bone Neoplasms; Carcinoma, Renal Cell; Denosumab; Exome Sequencing; Female; Gain of Function Mutation; Humans; Kidney Neoplasms; Liver Neoplasms; Magnetic Resonance Imaging; Mechanistic Target of Rapamycin Complex 1; Metastasectomy; Middle Aged; Mutation, Missense; Positron Emission Tomography Computed Tomography; Protein Kinase Inhibitors; Response Evaluation Criteria in Solid Tumors; Signal Transduction; Sirolimus; TOR Serine-Threonine Kinases; Treatment Outcome; Tumor Suppressor Proteins; Ubiquitin Thiolesterase

The current study was to examine the underlying mechanisms responsible for the role of mammalian target of rapamycin (mTOR) in regulating bone cancer-evoked pain and the tolerance of systemic morphine. Breast sarcocarcinoma Walker 256 cells were implanted into the tibia bone cavity of rats and this evoked significant mechanical and thermal hyperalgesia. Our results showed that the protein expression of p-mTOR, mTOR-mediated phosphorylation of 4E-binding protein 4 (4E-BP1), p70 ribosomal S6 protein kinase 1 (S6K1) as well as phosphatidylinositide 3-kinase (p-PI3K) pathways were amplified in the superficial dorsal horn of the spinal cord of bone cancer rats compared with control rats. Blocking spinal mTOR by using rapamycin significantly attenuated activities of PI3K signaling pathways as well as mechanical and thermal hyperalgesia. Additionally, rapamycin enhanced attenuations of protein kinase Cɛ (PKCɛ)/protein kinase A (PKA) induced by morphine and further extended analgesia of morphine via µ-opioid receptor (MOR). Our data for the first time revealed specific signaling pathways leading to bone cancer pain, including the activation of mTOR and PI3K and downstream PKCɛ/PKA, and resultant sensitization of MOR. Targeting one or more of these signaling molecules may present new opportunities for treatment and management of bone cancer pain often observed in clinics.

Topics: Analgesics, Opioid; Animals; Blotting, Western; Bone Neoplasms; Disease Models, Animal; Drug Tolerance; Morphine; Pain; Rats; Rats, Wistar; Receptors, Opioid, mu; Signal Transduction; Sirolimus; TOR Serine-Threonine Kinases

Multi-drug resistance poses a critical bottleneck in chemotherapy. Given the up-regulation of mTOR pathway in many chemoresistant cancers, we examined whether sirolimus (rapamycin), a first generation mTOR inhibitor, might induce human osteosarcoma (OS) cell apoptosis and increase the sensitivity of OS cells to anticancer drugs in vitro.. Human OS cell line MG63/ADM was treated with sirolimus alone or in combination with doxorubicin (ADM), gemcitabine (GEM) or methotrexate (MTX). Cell proliferation and apoptosis were detected using CCK-8 assay and flow cytometry, respectively. MiRNAs in the cells were analyzed with miRNA microarray. The targets of miR-34b were determined based on TargetScan analysis and luciferase reporter assays. The expression of relevant mRNA and proteins was measured using qRT-PCR and Western blotting. MiR-34, PAK1 and ABCB1 levels in 40 tissue samples of OS patients were analyzed using qRT-PCR and in situ hybridization assays.. Sirolimus (1-100 nmol/L) dose-dependently suppressed the cell proliferation (IC50=23.97 nmol/L) and induced apoptosis. Sirolimus (10 nmol/L) significantly sensitized the cells to anticancer drugs, leading to decreased IC50 values of ADM, GEM and MTX (from 25.48, 621.41 and 21.72 μmol/L to 4.93, 73.92 and 6.77 μmol/L, respectively). Treatment of with sirolimus increased miR-34b levels by a factor of 7.5 in the cells. Upregulation of miR-34b also induced apoptosis and increased the sensitivity of the cells to the anticancer drugs, whereas transfection with miR-34b-AMO, an inhibitor of miR-34b, reversed the anti-proliferation effect of sirolimus. Two key regulators of cell cycle, apoptosis and multiple drug resistance, PAK1 and ABCB1, were demonstrated to be the direct targets of miR-34b. In 40 tissue samples of OS patients, significantly higher miR-34 ISH score and lower PAK5 and ABCB1 scores were detected in the chemo-sensitive group.. Sirolimus increases the sensitivity of human OS cells to anticancer drugs in vitro by up-regulating miR-34b interacting with PAK1 and ABCB1. A low miR-34 level is an indicator of poor prognosis in OS patients.

Topics: Antineoplastic Agents; Apoptosis; Bone Neoplasms; Deoxycytidine; Doxorubicin; Drug Resistance, Multiple; Drug Resistance, Neoplasm; Drug Synergism; Gemcitabine; HEK293 Cells; Humans; Methotrexate; MicroRNAs; Osteosarcoma; Sirolimus

The predictive role of objective remission remains undefined for targeted agents in metastatic renal cell carcinoma (mRCC); however, early tumour shrinkage (eTS) was shown to be predictive and/or prognostic for overall survival (OS) and progression-free survival (PFS) in mRCC in several small studies.. To evaluate the degree of eTS following systemic therapy that may predict survival in mRCC.. Data from 4334 patients with mRCC in phase 2 and 3 clinical trials between 2003 and 2013 were pooled for analyses. Early tumour shrinkage was assessed based on percentage change in sum of the longest diameters of target lesions at first postbaseline scan. Patients were categorised by a more or equal versus less optimal threshold of eTS, assessed using receiver operating characteristic (ROC) analysis. OS and PFS in patients with eTS were summarised using the Kaplan-Meier method.. Axitinib, bevacizumab, interferon α, sorafenib, sunitinib, or temsirolimus.. We measured optimal thresholds of eTS and eTS as a predictor of OS or PFS.. Optimal threshold of eTS for the prediction of OS and PFS was determined to be approximately 10%. In Cox proportional hazards models, compared with patients without eTS, those with eTS had significantly longer OS (hazard ratio [HR]: 0.615; p<0.0001; median: 28.5 vs 16.0 mo) and PFS (HR: 0.628; p<0.0001; median: 10.5 vs 5.3 mo). The major limitation was the retrospective nature of our analysis, including different lines and types of therapy, although subset analyses detected a similar predictive pattern for eTS across all lines and types of therapy.. Early tumour shrinkage ≥10% at first postbaseline assessment could serve as a putative early end point in patients with mRCC. A prospective evaluation of eTS in clinical trials is warranted.. Early tumour shrinkage may be used to identify patients with metastatic renal cell carcinoma who would benefit from treatment with antitumour agents.. The clinical trials are registered on ClinicalTrials.gov (NCT00267748, NCT00338884, NCT00835978, NCT00065468, NCT00083889, NCT00631371, NCT00920816, NCT00077974, NCT00137423, NCT00054886, NCT00678392, and NCT00474786).

Topics: Aged; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Axitinib; Bevacizumab; Bone Neoplasms; Carcinoma, Renal Cell; Clinical Trials, Phase II as Topic; Clinical Trials, Phase III as Topic; Disease-Free Survival; Humans; Imidazoles; Indazoles; Indoles; Interferon-alpha; Kidney Neoplasms; Liver Neoplasms; Lung Neoplasms; Male; Middle Aged; Neoplasm Metastasis; Niacinamide; Phenylurea Compounds; Prognosis; Proportional Hazards Models; Pyrroles; Remission Induction; Retrospective Studies; Sirolimus; Sorafenib; Sunitinib; Survival Rate; Treatment Outcome; Tumor Burden

To evaluated patterns and outcomes of hepatocellular carcinoma (HCC) recurrence after living donor liver transplantation (LDLT).. From 2001 to 2014, 293 patients underwent LDLT for HCC at our transplant center. We retrospectively reviewed 54 (18.4%) patients with HCC recurrence after LDLT. We evaluated patterns and outcomes of HCC recurrence after LDLT, with particular attention to the Milan criteria at transplantation, treatments for HCC-recurrent patients, and factors related to survival after HCC recurrence. Furthermore, we evaluated the efficacy of combination treatment of sorafenib and an mTOR inhibitor.. The 1-, 2-, and 3-year overall survival rates after HCC recurrence were 41.1%, 20.5%, and 15.4%, respectively. The median time interval between LDLT and HCC recurrence was 6.5 mo. Although recurrence rates according to the Milan criteria at LDLT were significantly different, HCC recurrence patterns and survival rates after HCC recurrence were not significantly different between the two groups. Time to recurrence < 12 mo (P = 0.048), multiple recurrences at HCC recurrence (P = 0.038), and palliative treatment for recurrent tumors (P = 0.003) were significant independent prognostic factors for poor survival after HCC recurrence in a multivariate analysis. The combination treatment of sorafenib and sirolimus showed survival benefits in the palliative treatment group (P = 0.005).. Curative treatment for recurrent HCC after LDLT is the most important factor in survival rates after HCC recurrence and combination treatments of sorafenib and an mTOR inhibitor could have survival benefits in patients with HCC recurrence after LT in the palliative treatment group.

Topics: Adult; Antineoplastic Agents; Bone Neoplasms; Carcinoma, Hepatocellular; Female; Humans; Liver Neoplasms; Liver Transplantation; Living Donors; Lung Neoplasms; Male; Middle Aged; Multivariate Analysis; Neoplasm Recurrence, Local; Niacinamide; Phenylurea Compounds; Retrospective Studies; Sirolimus; Sorafenib

Therapies cotargeting insulin-like growth factor receptor 1 (IGF-1R) and mammalian target of rapamycin (mTOR) have demonstrated remarkable, albeit short-lived, clinical responses in a subset of Ewing sarcoma (ES) patients. However, the mechanisms of resistance and applicable strategies for overcoming drug resistance to the IGF-1R/mTOR blockade are still undefined.. To elucidate predominant mechanism(s) of acquired drug resistance while identifying synergistic drug combinations that improve clinical efficacy, we generated more than 18 ES cell lines resistant to IGF-1R- or mTOR-targeted therapy. Two small-molecule inhibitors of IGF-1R were chosen, NVP-ADW-742 (IGF-1R-selective) and OSI-906 (a dual IGF-1R/insulin receptor alpha [IR-α] inhibitor). Reverse-phase protein lysate arrays (RPPAs) revealed proteomic changes linked to IGF-1R/mTOR resistance, and selected proteins were validated in cell-based assays, xenografts, and within human clinical samples. All statistical tests were two-sided.. Novel mechanisms of resistance (MOR) emerged after dalotuzumab-, NVP-ADW-742-, and OSI-906-based targeting of IGF-1R. MOR to dalotuzumab included upregulation of IRS1, PI3K, and STAT3, as well as p38 MAPK, which was also induced by OSI-906. pEIF4E(Ser209), a key regulator of Cap-dependent translation, was induced in ridaforolimus-resistant ES cell lines. Unique drug combinations targeting IGF-1R and PI3K-alpha or Mnk and mTOR were synergistic in vivo and vitro (P < .001) as assessed respectively by Mantel-Cox and isobologram testing.. We discovered new druggable targets expressed by chemoresistant ES cells, xenografts, and relapsed human tumors. Joint suppression of these newfound targets, in concert with IGF-1R or mTOR blockade, should improve clinical outcomes.

Topics: Adenosine Triphosphatases; Animals; Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Antineoplastic Combined Chemotherapy Protocols; Bone Neoplasms; Cation Transport Proteins; Cell Line, Tumor; Copper-Transporting ATPases; Drug Resistance, Neoplasm; Drug Synergism; Humans; Imidazoles; Insulin Receptor Substrate Proteins; Male; Mice; Mice, SCID; Neoplasm Transplantation; Nucleocytoplasmic Transport Proteins; p38 Mitogen-Activated Protein Kinases; Phosphatidylinositol 3-Kinase; Phosphoinositide-3 Kinase Inhibitors; Protein Array Analysis; Pyrazines; Pyrimidines; Pyrroles; Receptor, IGF Type 1; Receptors, Somatomedin; Sarcoma, Ewing; Sirolimus; STAT3 Transcription Factor; TOR Serine-Threonine Kinases; Up-Regulation

Topics: Aged; Bone Neoplasms; Carcinoma, Renal Cell; Disease Progression; Humans; Kidney Neoplasms; Male; Mechanistic Target of Rapamycin Complex 1; Multiprotein Complexes; Protein Kinase Inhibitors; Sirolimus; TOR Serine-Threonine Kinases; Treatment Outcome

In advanced breast cancer, bone metastases occur in 70 % of patients. Managing the devastating pain associated with the disease is difficult. Rapamycin is an immunomodulatory drug that targets the mammalian target of rapamycin pathway. Rapamycin has been shown to decrease osteolysis associated with metastatic breast cancer in pre-clinical models and to reduce pain in inflammatory and neuropathic models. The aim of this study was to evaluate the effectiveness of rapamycin in reducing pain associated with experimental osteolytic metastases. Bone cancer was induced by intra-tibial injections of murine mammary carcinoma cells (4T1) in immunocompetent BALB/c mice and treated intraperitoneally for up to 5 weeks with vehicle, rapamycin or pamidronate (a bisphosphonate currently used to reduce bone loss in bone cancer patients). The control group received intra-tibial injection with saline (sham) and was treated with vehicle intraperitoneally. Cancer-induced osteolysis was observed histologically and radiographically 2-3 weeks following cancer inoculation and gradually increased with time. Measures of evoked nociceptive behaviors including sensitivity to mechanical, thermal, and cold stimuli and spontaneous nociceptive behaviors (limping, guarding) were evaluated. Significant hypersensitivity to sensory stimuli developed in cancer-bearing mice compared to sham 3 weeks following inoculation. Rapamycin decreased or delayed the development of cancer-induced mechanical, heat, and cold hypersensitivity, while pamidronate reduced heat and cold hypersensitivity. Both rapamycin and pamidronate had a partial protective effect on the spontaneous nociceptive behaviors, limping and guarding. Our data suggest that rapamycin may have efficacy in the management of pain associated with metastatic breast cancer.

Topics: Animals; Antibiotics, Antineoplastic; Bone Density Conservation Agents; Bone Neoplasms; Cell Line, Tumor; Diphosphonates; Disease Models, Animal; Female; Mammary Neoplasms, Experimental; Mice; Mice, Inbred BALB C; Osteolysis; Pain; Pain Measurement; Pamidronate; Sirolimus; TOR Serine-Threonine Kinases

Bone metastases (BMs) are frequently present in patients with metastatic renal cell carcinoma (mRCC) and cause significant morbidity.. The purpose of this analysis was to assess the impact of BMs and bisphosphonate therapy (BT) on outcomes in mRCC.. We conducted a pooled analysis of patients with mRCC treated from 2003 to 2011 in phase 2 and 3 trials.. Statistical analyses were performed using Cox regression and the Kaplan-Meier method.. We identified 2749 patients treated with sunitinib (n=1059), sorafenib (n=355), axitinib (n=359), temsirolimus (n=208), temsirolimus plus interferon-α (IFN-α) (n=208), or IFN-α (n=560), with 28% (n=781) having BMs. A total of 285 patients (10.4%) received BT. The presence of BMs in patients was associated with shorter overall survival (OS) when compared with patients without BMs (13.2 vs 20.2 mo, respectively; p<0.0001) and shorter progression-free survival (PFS) (5.1 vs 6.7 mo, respectively; p<0.0008). When stratified by risk groups, the presence of BMs was associated with shorter OS in all risk groups. The use of BT in patients with BMs was not associated with improved OS compared with patients who did not receive BT (13.3 vs 13.1 mo, respectively; p=0.3801) or improved PFS (5.1 vs 4.9 mo, respectively; p=0.1785). Bisphosphonate users with BMs did not have a decreased rate of skeletal-related events (SREs) compared with nonusers (8.6% vs 5.8%, respectively; p=0.191). In addition, BT was associated with increased rates of hypocalcemia, renal insufficiency, and osteonecrosis of the jaw (p<0.0001). Data were analyzed retrospectively.. We confirm that the presence of BMs is associated with shorter survival in mRCC. BT did not affect survival or SRE prevention and was associated with increased toxicity.. In this analysis, we demonstrate that bone metastases are associated with shorter survival in patients with metastatic renal cell carcinoma. In addition, we call into question the utility of bisphosphonate therapy in this population.

Topics: Aged; Antineoplastic Agents; Axitinib; Bisphosphonate-Associated Osteonecrosis of the Jaw; Bone Density Conservation Agents; Bone Neoplasms; Carcinoma, Renal Cell; Diphosphonates; Disease-Free Survival; Female; Humans; Hypocalcemia; Imidazoles; Indazoles; Indoles; Interferon-alpha; Kidney Neoplasms; Male; Middle Aged; Niacinamide; Pamidronate; Phenylurea Compounds; Prognosis; Pyrroles; Renal Insufficiency; Retrospective Studies; Sirolimus; Sorafenib; Sunitinib; Survival Rate; TOR Serine-Threonine Kinases; Vascular Endothelial Growth Factor A; Zoledronic Acid

Mammalian target of rapamycin (mTOR) is a new promising oncological target. However, most clinical studies reported only modest antitumor activity during mTOR-targeted monotherapies, including studies in osteosarcomas, emphasizing a need for improvement. We hypothesized that the combination with rationally selected other therapeutic agents may improve response. In this study, we examined the efficacy of the mTOR inhibitor temsirolimus combined with cisplatin or bevacizumab on the growth of human osteosarcoma xenografts (OS-33 and OS-1) in vivo, incorporating functional imaging techniques and microscopic analyses to unravel mechanisms of response. In both OS-33 and OS-1 models, the activity of temsirolimus was significantly enhanced by the addition of cisplatin (TC) or bevacizumab (TB). Extensive immunohistochemical analysis demonstrated apparent effects on tumor architecture, vasculature, apoptosis and the mTOR-pathway with combined treatments. 3'-Deoxy-3'-(18) F-fluorothymidine ((18) F-FLT) positron emission tomography (PET) scans showed a remarkable decrease in (18) F-FLT signal in TC- and TB-treated OS-1 tumors, which was already noticeable after 1 week of treatment. No baseline uptake was observed in the OS-33 model. Both immunohistochemistry and (18) F-FLT-PET demonstrated that responses as determined by caliper measurements underestimated the actual tumor response. Although (18) F-FLT-PET could be used for accurate and early response monitoring for temsirolimus-based therapies in the OS-1 model, we could not evaluate OS-33 tumors with this molecular imaging technique. Further research on the value of the use of (18) F-FLT-PET in this setting in osteosarcomas is warranted. Overall, these findings urge the further exploration of TC and TB treatment for osteosarcoma (and other cancer) patients.

Topics: Angiogenesis Inhibitors; Animals; Antibodies, Monoclonal, Humanized; Antineoplastic Combined Chemotherapy Protocols; Bevacizumab; Bone Neoplasms; Cell Line, Tumor; Cisplatin; Dideoxynucleosides; Female; Fluorodeoxyglucose F18; Humans; Mice; Mice, Inbred BALB C; Mice, Nude; Osteosarcoma; Positron-Emission Tomography; Protein Kinase Inhibitors; Sirolimus; Tomography, X-Ray Computed; TOR Serine-Threonine Kinases; Xenograft Model Antitumor Assays

Non-small-cell lung cancer (NSCLC) frequently metastasizes to bone. It is known that zoledronic acid is cytostatic to tumors, and everolimus, the inhibitor for mammalian target of the rapamycin, could inhibit many types of cancer. Herein, we evaluated the effect of zoledronic acid alone and in combination with everolimus on treating lung adenocarcinoma bone metastasis in vitro and in vivo. Mice treated with zoledronic acid in combination with everolimus had more apoptotic lung cancer cells and more cells were arrested in the G1/G0 phase. The phosphorylation of p70S6K was inhibited in the combination treatment group. Lung cancer cell invasion was also significantly inhibited in the group with combination treatment in vitro. Bone nuclear scans revealed more metastatic lesions in controls compared with those in the combination treatment group. Bone scans and radiographic images indicated that combination therapy significantly reduced bone metastasis. The moderate survival rate suggested that the drug combination was synergistic, which can delay NSCLC bone metastasis and prolong survival in vivo.

Topics: Animals; Apoptosis; Bone Neoplasms; Cell Line, Tumor; Diphosphonates; Drug Synergism; Drug Therapy, Combination; Everolimus; Humans; Imidazoles; Lung Neoplasms; Mice; Neoplasm Invasiveness; Phosphorylation; Ribosomal Protein S6 Kinases, 70-kDa; Sirolimus; Zoledronic Acid

Topics: Androstadienes; Antineoplastic Agents; Bone Neoplasms; Breast Neoplasms; Drug Therapy, Combination; Everolimus; Female; Humans; Liver Neoplasms; Middle Aged; Neoplasms, Second Primary; Radiodermatitis; Radiotherapy, Adjuvant; Sirolimus

Topics: Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Antineoplastic Combined Chemotherapy Protocols; Bone Neoplasms; Female; Humans; Male; Sarcoma; Sirolimus

To investigate the efficacy and safety of zoledronic acid (ZA) combined with targeted therapy (TT).. A retrospective study was performed in patients with metastatic renal cell carcinoma treated with ZA and TT.. Twenty-one patients received ZA and TT to prevent skeletal-related events and no pretherapy oral and maxillofacial (OM) examination (cohort A). Six patients (29%) developed osteonecrosis of the jaw (ONJ), which was observed only in patients receiving sunitinib and ZA. Sixteen patients received TT and ZA for hypercalcemia and no pretherapy OM examination (cohort B). In these patients, no ONJ was observed. Nine patients received ZA and TT and pretherapy OM examination (cohort C). One patient (11%) developed ONJ during sunitinib and ZA treatment. Mean skeletal morbidity rates were 0.8 for cohort A and 1.2 for cohort C. In the combined cohort (A plus C; n = 30), 47% developed skeletal-related events, 7% pathologic fracture, 7% medullary compression, and 37% progression of bone metastases. Patients who developed ONJ had a significantly improved median survival of 31.6 months compared with 14.5 months in patients without ONJ (P = .039).. The combination of ZA and TT resulted in high, clinically meaningful activity. ONJ may be exacerbated by concomitant ZA and sunitinib. Regular OM examinations before and during treatment are recommended.

Topics: Adult; Aged; Angiogenesis Inhibitors; Antibodies, Monoclonal, Humanized; Antineoplastic Agents; Bevacizumab; Bisphosphonate-Associated Osteonecrosis of the Jaw; Bone Density Conservation Agents; Bone Neoplasms; Carcinoma, Renal Cell; Cohort Studies; Diphosphonates; Everolimus; Female; Follow-Up Studies; Fractures, Spontaneous; Humans; Imidazoles; Indazoles; Indoles; Interleukin-2; Kidney Neoplasms; Male; Middle Aged; Molecular Targeted Therapy; Niacinamide; Phenylurea Compounds; Pyrimidines; Pyrroles; Radiography, Panoramic; Retrospective Studies; Sirolimus; Sorafenib; Spinal Cord Compression; Sulfonamides; Sunitinib; Survival Rate; Zoledronic Acid

Renal cell carcinoma (RCC) is a histopathologically and molecularly heterogeneous disease with the chromophobe subtype (chRCC) accounting for approximately 5% of all cases. The median overall survival of advanced RCC has improved significantly since the advent of tyrosine kinase inhibitors and mammalian target of rapamycin (mTOR) inhibitors. However, high-quality evidence for the use of new generation tyrosine kinase inhibitors in patients with advanced chRCC is lacking. Few published case reports have highlighted the use of temsirolimus in chRCC.. Here, we report the case of a 36-year-old Caucasian woman with metastatic chRCC with predominantly skeletal metastases who was refractory to sunitinib who demonstrated a durable clinical response to temsirolimus lasting 20 months. We review the available evidence pertaining to the use of new generation molecularly targeted agents, in particular mTOR inhibitors in chRCC and discuss their emerging role in the management of this disease which would aid the oncologists faced with the challenge of treating this rare type of RCC.. Conducting randomised clinical trials in this rarer sub-group of patients would be challenging and our case report and the evidence reviewed would guide the physicians to make informed decision regarding the management of these patients.

Topics: Adult; Antineoplastic Agents; Bone Neoplasms; Carcinoma, Renal Cell; Female; Humans; Kidney Neoplasms; Sirolimus; Treatment Outcome

The mTOR pathway is a central control of cell growth, proliferation, metabolism, and survival, and is deregulated in most cancers. Cancer cells are addicted to increased activity of mTOR kinase-mediated signaling pathways, leading to numerous inhibitors of mTOR signaling in preclinic and clinical trials for cancer therapy. Phosphorus-containing sirolimus (FIM-A), which targets mTOR signaling, inhibits cancer cell growth in vitro. Here we report that FIM-A reduces the angiogenesis and proliferation of osteosarcoma both in vitro and in vivo. In cultured osteosarcoma cell lines, FIM-A inhibited cell proliferation and arrested cells in the G1 phase of the cell cycle, accompanied with reduction of VEGF and HIF-1alpha. With in vivo mouse osteosarcoma xenografts, FIM-A treatment resulted in the inhibition of mTORC1 signaling as demonstrated by the decreased phosphorylation of p70S6K1 and 4E-BP1. Consistent with this finding, FIM-A significantly decreased the average tumor volume, nuclei staining of PCNA, and the number of intratumoral microvessels. Our data demonstrated that targeting mTORC1 by FIM-A inhibited the growth of osteosarcoma in vitro and in vivo, providing the basis for further development of FIM-A as a therapy for osteosarcoma patients.

Topics: Angiogenesis Inhibitors; Animals; Antineoplastic Agents; Bone Neoplasms; Cell Line, Tumor; Cell Proliferation; Female; Humans; Mechanistic Target of Rapamycin Complex 1; Mice; Mice, Inbred BALB C; Multiprotein Complexes; Neovascularization, Pathologic; Osteosarcoma; Phosphorus; Sirolimus; TOR Serine-Threonine Kinases; Xenograft Model Antitumor Assays

To observe the effect of rapamycin on the MG-63 osteosarcoma cells (OC), osteosarcoma stem cells (OSC) and on mTOR signaling pathway, and explore the feasibility of rapamycin as a novel therapeutic measure in osteosarcoma chemotherapy regimens.. OC and OSC were cultured in vitro. Immunofluorescence assay was used to detect the expression of Nanog and Oct4 in OC and OSC. OC and OSC were treated with rapamycin in concentrations of 0, 20, 50 and 100 nmol/L. Semi-quantitative PCR and RT-PCR were used to detect the mTOR mRNA and CCK-8 assay was used to detect cell proliferation, and the cell morphology was observed under an inverted microscope.. The cores of MG-63 cellular spheres exhibited embryonic stem cell characteristics such as Nanog and Oct4 expession. The mTOR pathway was activated in the OSC and the expression of mTOR mRNA was higher in OSC (0.761 ± 0.080) than that in OS (0.406 ± 0.090, P < 0.05) by semi-quantitative PCR. RT-PCR showed that the expression of mTOR mRNA was lower in OSCs treated with 100 nmol/L rapamycin (0.961 ± 0.060) than that with 0 nmol/L rapamycin (1.654 ± 0.246, P < 0.05). Cell counting kit-8 (CCK-8) assay showed that the proliferation of OC treated with 20, 50 and 100 nmol/L rapamycin was significantly inhibited, compared with that with 0 nmol/L rapamycin (P < 0.05). Compared with 0 nmol/L rapamycin, the proliferation of OSC treated with 20 and 50 nmol/L rapamycin was not significantly inhibited (P > 0.05), but that with 100 nmol/L rapamycin was significantly inhibited (P < 0.05). The invert microscopic observation revealed that rapamycin inhibited the formation of OSC spheres.. Rapamycin can effectively inhibit cell proliferation and the ability of sphere formation of OSCs. It will provide a basis for a novel therapeutic approach in osteosarcoma chemotherapy regimens.

Topics: Antibiotics, Antineoplastic; Bone Neoplasms; Cell Line, Tumor; Cell Proliferation; Cells, Cultured; Dose-Response Relationship, Drug; Homeodomain Proteins; Humans; Nanog Homeobox Protein; Neoplastic Stem Cells; Octamer Transcription Factor-3; Osteosarcoma; RNA, Messenger; Signal Transduction; Sirolimus; TOR Serine-Threonine Kinases

Topics: Antineoplastic Agents; Bone Neoplasms; Carcinoma, Renal Cell; Female; Humans; Kidney Neoplasms; Liver Neoplasms; Male; Niacinamide; Phenylurea Compounds; Sirolimus

Although (177)Lu-octreotate is an effective treatment for patients with gastroenteropancreatic neuroendocrine tumors (GEP-NETs), some patients will fail or develop disease progression necessitating further treatment. We examined whether the safety and efficacy of everolimus after prior treatment with (177)Lu-octreotate is different from the published safety profile of everolimus in GEP-NETs. In this multicenter study, 24 GEP-NET patients were included. Adverse events were assessed according to the National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE), version 3.0. Tumor response was measured according to the Response Evaluation Criteria in Solid Tumors (RECIST), version 1.0. Major clinical adverse events (grade 3 or 4) during treatment with everolimus were hyperglycemia (20.8%), fatigue (8.3%), thrombocytopenia (8.3%), and elevated alanine transaminase levels (8.3%). By radiological review, there were four partial responses (16.7%), five patients (62.5%) with stable disease, and three patients (12.5%) with progressive disease. For two patients (8.3%), no data on tumor response were available. Median progression-free survival (PFS) was 13.1 months (95% CI, 11.5-21.2). Median PFS of the current study was longer when compared with the RADIANT-3 trial (13.1 vs 11.4 months) and shorter when compared with the RADIANT-1 trial (13.1 vs 16.7 months). In conclusion, the safety profile of everolimus is not influenced by previous treatment with peptide receptor radiotherapy.

Topics: Adult; Aged; Bone Neoplasms; Everolimus; Female; Follow-Up Studies; Humans; Immunosuppressive Agents; Intestinal Neoplasms; Liver Neoplasms; Lutetium; Lymphatic Metastasis; Male; Middle Aged; Neoplasm Staging; Neuroendocrine Tumors; Octreotide; Pancreatic Neoplasms; Prognosis; Retrospective Studies; Safety; Sirolimus; Stomach Neoplasms; Survival Rate

Antiresorptive agent-related osteonecrosis of the jaw results in appreciable morbidity in affected patients. Nowadays many physicians prescribe an antiangiogenic agent for the management of malignant metastases. Everolimus is a serine-threonine kinase that acts as an inhibitor of mammalian target of rapamycin, which results in reduced growth of cells, angiogenesis, and survival of cells. We report the first case to our knowledge of osteonecrosis of the jaw that seemed to result from the additive effect of everolimus.

Topics: Angiogenesis Inhibitors; Bone Density Conservation Agents; Bone Neoplasms; Diphosphonates; Everolimus; Follow-Up Studies; Humans; Imidazoles; Male; Mandibular Diseases; Middle Aged; Osteonecrosis; Sirolimus; Thyroid Neoplasms; Thyroidectomy; Zoledronic Acid

Osteoprotegerin (OPG) is a decoy receptor for the Receptor of NF-κB (RANK) ligand that can inhibit osteoclastogenesis. Previous studies have suggested that Mammalian Target of Rapamycin (mTOR) inhibition upregulates OPG production. We tested the hypothesis that the mTOR inhibitor rapamycin could inhibit neuroblastoma bone metastases through its action on OPG.. An orthotopic model of bone metastasis was established. Mice with established disease were subsequently treated with rapamycin (5mg/kg IP daily) or vehicle control (DMSO 1:1000). X-rays were obtained twice a week to detect pathologic fractures. Serum OPG levels were measured by ELISA after two weeks of treatment.. Mice with bone disease receiving rapamycin had increased serum levels of OPG in the CHLA-20 mice compared to controls (36.89 pg/mL ± 3.90 vs 18.4 pg/mL ± 1.67, p=0.004) and NB1691 tumor-bearing groups (46.03 ± 2.67 pg/mL vs 17.96 ± 1.84pg/mL, p=0.001), and a significantly longer median time to pathologic fractures with CHLA-20 (103 days vs 74.5 days, p=0.014) and NB1691 xenografts.. In a xenograft model, increased OPG expression correlated with a delay to pathologic fracture suggesting a potential role for mTOR inhibitors in the treatment of neuroblastoma bone metastases.

Topics: Animals; Antibiotics, Antineoplastic; Antineoplastic Combined Chemotherapy Protocols; Biomarkers; Bone Neoplasms; Cell Line, Tumor; Dose-Response Relationship, Drug; Drug Administration Schedule; Enzyme-Linked Immunosorbent Assay; Fractures, Spontaneous; Humans; Injections, Intraperitoneal; Mice; Mice, SCID; Neuroblastoma; Osteoprotegerin; Reverse Transcriptase Polymerase Chain Reaction; Sirolimus; Treatment Outcome

Breast cancer metastasis to bone results in pain, pathological fractures and hypercalcemia. Activation of osteoclasts is critical for the formation of osteolytic lesions by metastasizing tumors. Although the potent drugs, zoledronic acid and Denosumab were introduced, the presence of resistant or intolerant cases necessitated the continued search of osteoclast-targeting treatments. Rapamycin acts through the mTOR pathway, which is important for osteoclast formation. Mouse mammary carcinoma 4T1 cells were injected into the tibia of balb/c mice. Rapamycin treatment significantly decreased the osteoclast population and osteolysis associated with experimental metastases. Our data indicate the benefit of rapamycin in treating metastases-associated osteolytic disease.

Topics: Animals; Bone Neoplasms; Cells, Cultured; Female; Mammary Neoplasms, Experimental; Mice; Mice, Inbred BALB C; Osteoblasts; Osteoclasts; Osteolysis; Sirolimus

Giant cell tumor (GCT) of bone is a benign type of tumor, but the presence of hyperactive multinucleated giant osteoclasts cause local osteolytic lesions, increasing morbidity in patients. To specifically target hyperactive multinucleated giant osteoclasts in GCTs, one would envisage the usage of osteoclast inhibitors or genetic modulation of osteoclastogenesis. Recently, we have found that the translationally regulated balance between the transcription factor C/EBPβ long (LAP) and short (LIP) protein isoforms regulates osteoclast differentiation. Here, we report that GCTs express high levels of the LIP C/EBPβ isoform, which in mice cause giant osteoclast formation. In mice, inhibition of mTOR activity by rapamycin decreased osteoclast differentiation by shifting the alternative translation initiation of C/EBPβ isoforms towards LAP. Similarly, rapamycin treatment of GCT cell cultures derived from seven different patients strongly reduced formation of giant osteoclasts and bone resorption. This was accompanied by an increase in MafB, previously shown to be the mediator of the effect of rapamycin on osteoclast differentiation in mice. These data suggest that C/EBPβ is a determinant of giant osteoclast formation in GCT and that pharmacological adjustment of the C/EBPβ isoform ratio could serve as a potential novel therapeutic approach.

Topics: Antibiotics, Antineoplastic; Bone Neoplasms; Bone Resorption; CCAAT-Enhancer-Binding Protein-beta; Cells, Cultured; Giant Cell Tumor of Bone; Humans; MafB Transcription Factor; Osteoclasts; Protein Transport; Sirolimus

Topics: Antineoplastic Agents; Bone Neoplasms; Female; Humans; Male; Sarcoma; Sirolimus; TOR Serine-Threonine Kinases

Chondrosarcomas are the second most frequent primary malignant type of bone tumor. No effective systemic treatment has been identified in advanced or adjuvant phases for chondrosarcoma. The aim of the present study was to determine the antitumor effects of doxorubicin and everolimus, an mTOR inhibitor on chondrosarcoma progression.. Doxorubin and/or everolimus were tested in vivo as single agent or in combination in the rat orthotopic Schwarm chondrosarcoma model, in macroscopic phase, as well as with microscopic residual disease. Response to everolimus and/or doxorubicin was evaluated using chondrosarcoma volume evolution (MRI). Histological response was evaluated with % of tumor necrosis, tumor proliferation index, metabolism quantification analysis between the treated and control groups. Statistical analyses were performed using chi square, Fishers exact test. Doxorubicin single agent has no effect of tumor growth as compared to no treatment; conversely, everolimus single agent significantly inhibited tumor progression in macroscopic tumors with no synergistic additive effect with doxorubicin. Everolimus inhibited chondrosarcoma proliferation as evaluated by Ki67 expression did not induce the apoptosis of tumor cells; everolimus reduced Glut1 and 4EBP1 expression. Importantly when given in rats with microscopic residual diseases, in a pseudo neoadjuvant setting, following R1 resection of the implanted tumor, everolimus significantly delayed or prevented tumor recurrence.. MTOR inhibitor everolimus blocks cell proliferation, Glut1 expression and HIF1a expression, and prevents in vivo chondrosarcoma tumor progression in both macroscopic and in adjuvant phase post R1 resection. Taken together, our preclinical data indicate that mTOR inhibitor may be effective as a single agent in treating chondrosarcoma patients. A clinical trial evaluating mTOr inhibitor as neo-adjuvant and adjuvant therapy in chondrosarcoma patients is being constructed.

Topics: Animals; Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Blotting, Western; Bone Neoplasms; Cell Proliferation; Chondrosarcoma; Disease Models, Animal; Doxorubicin; Everolimus; Humans; Male; Neoplasm Recurrence, Local; Rats; Real-Time Polymerase Chain Reaction; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Sirolimus; TOR Serine-Threonine Kinases

We previously reported that caffeine-assisted chemotherapy improved the treatment of malignant bone and soft tissue tumours such as osteosarcoma. Caffeine affects tumour cells through various pathways, including phosphatase and tensin homolog deleted on chromosome 10 (PTEN), AKT, Bcl-2-associated X protein (BAX), caspase-3 and p53, and has therefore been indicated as being useful for the treatment of malignant tumours. Here, the effects of caffeine on the proliferation of HOS osteosarcoma cells were assessed by WST-8 assay, and the effects on the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), mammalian target of rapamycin (mTOR) and mitogen-activated protein kinase (MAPK) pathways were assessed by western blot analyses. Caffeine inhibited proliferation of HOS cells and suppressed NF-κB, AKT, mTOR/S6K and ERK activities. Our results support those from previous studies relating to the use of caffeine in the treatment of osteosarcoma.

Topics: Apoptosis; Bone Neoplasms; Caffeine; Cell Line, Tumor; Dose-Response Relationship, Drug; Humans; MAP Kinase Signaling System; NF-kappa B; Osteosarcoma; Phosphorylation; Proto-Oncogene Proteins c-akt; Sirolimus; TOR Serine-Threonine Kinases

Chondrosarcomas (CS) represent a heterogeneous group of rare sarcomas, poorly responsive to chemotherapy or radiotherapy. When local therapies in recurrent or metastatic disease are exhausted, chemotherapy plays a marginal role. Different molecular pathways have been shown to be activated in CS. In this retrospective study, we summarize our experience in treating a cohort of patients with recurrent unresectable CS with a combination of sirolimus (SIR) and cyclophosphamide (CTX).. Ten consecutive patients with unresectable CS were offered off-label treatment with SIR and CTX between 2007 and 2012. Tumor response, progression-free survival (PFS), adverse events, and other relevant clinical data were analyzed.. The median patients' age was 49 (range 28-68). Median disease-free interval since the primary diagnosis was 22.5 months. Median time from the disease recurrence to initiation of SIR and CTX treatment was 21.7 months due to additional local surgical treatments, excision of metastases, or slow asymptomatic progression. One (10 %) objective response was observed, and six (60 %) patients had stabilization of disease for at least 6 months. Three patients had progressive disease. Median PFS was 13.4 months (range 3-30.3). No significant adverse events were observed.. Although advanced CS remains an incurable disease, our experience suggests that a combination of SIR and CTX is well tolerated and may have meaningful clinical activity with disease control rate of 70 %. Further prospective studies are warranted.

Topics: Adult; Aged; Antibiotics, Antineoplastic; Antineoplastic Agents, Alkylating; Antineoplastic Combined Chemotherapy Protocols; Bone Neoplasms; Chondrosarcoma; Cyclophosphamide; Disease-Free Survival; Female; Humans; Male; Middle Aged; Retrospective Studies; Sirolimus; TOR Serine-Threonine Kinases; Treatment Outcome

Ewing's and osteogenic sarcoma are two of the leading causes of cancer deaths in children and adolescents. Recent data suggest that sarcomas may depend on the insulin-like growth factor type 1 (IGF-1) receptor (IGF1R) and/or the insulin receptor (INSR) to drive tumor growth, survival, and resistance to mammalian target of rapamycin complex 1 (mTORC1) inhibitors. We evaluated the therapeutic value of ganitumab (AMG 479; C(6472)H(10028)N(1728)O(2020)S(42)), an anti-IGF1R, fully human monoclonal antibody, alone and in combination with rapamycin (mTORC1 inhibitor) in Ewing's (SK-ES-1 and A673) and osteogenic (SJSA-1) sarcoma models. IGF1R was activated by IGF-1 but not by insulin in each sarcoma model. INSR was also activated by IGF-1 in the SJSA-1 and SK-ES-1 models, but not in the A673 model where insulin was the preferred INSR ligand. Ganitumab significantly inhibited the growth of SJSA-1 and SK-ES-1 xenografts; inhibition was associated with decreased IGF1R and Akt phosphorylation, reduced total IGF1R and bromodeoxyuridine detection, and increased caspase-3 expression. Ganitumab inhibited rapamycin-induced IGF1R, Akt, and glycogen synthase kinase-3β hyperphosphorylation in each sarcoma model. However, ganitumab in combination with rapamycin also resulted in a marked increase in INSR expression and activity in the SJSA-1 and A673 models. The in vivo efficacy of ganitumab in the two ganitumab-sensitive models (SJSA-1 and SK-ES-1) was significantly enhanced in combination with rapamycin. Our results support studying ganitumab in combination with mTORC1 inhibitors for the treatment of sarcomas and suggest that INSR signaling is an important mechanism of resistance to IGF1R blockade.

Topics: Animals; Antibiotics, Antineoplastic; Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Antineoplastic Combined Chemotherapy Protocols; Bone Neoplasms; Caspase 3; Cell Line, Tumor; Cell Proliferation; Female; Humans; Insulin-Like Growth Factor I; Mice; Mice, Nude; Osteosarcoma; Phosphorylation; Receptor, IGF Type 1; Receptor, Insulin; Sarcoma, Ewing; Signal Transduction; Sirolimus; Xenograft Model Antitumor Assays

A 53-year-old female patient presented with cough and hoarseness for 3 years. Based on a biopsy of a bronchial tumor, a small cell neuroendocrine tumor of the lung was diagnosed and chemotherapy with etoposide and cisplatin was initiated. As the tumor progressed under chemotherapy, the bronchial biopsy was reevaluated and further biopsies of liver and adrenal metastases were obtained. The diagnosis was corrected, and an atypical neuroendocrine bronchial carcinoma was diagnosed. Under octreotide therapy, the patient remained stable for 1 year, when a discrete progress of the primary tumor in the lung was observed. Treatment with the mTOR (mammalian target of rapamycin) inhibitor everolimus was then initiated. Based on this case, the diagnostic criteria, prognostic factors and therapeutic options of neuroendocrine bronchial carcinomas are discussed.

Topics: Adrenal Gland Neoplasms; Adrenal Glands; Antineoplastic Combined Chemotherapy Protocols; Biomarkers, Tumor; Bone Neoplasms; Calcitonin; Carcinoma, Bronchogenic; Carcinoma, Medullary; Carcinoma, Neuroendocrine; Cell Division; Female; Humans; Ki-67 Antigen; Liver; Liver Neoplasms; Lung; Lung Neoplasms; Middle Aged; Neoplasm Staging; Neoplasms, Multiple Primary; Octreotide; Paraneoplastic Syndromes; Sirolimus; Thyroid Gland; Thyroid Neoplasms

The mammalian target of rapamycin (mTOR) is engaged in the molecular pathogenesis of oral squamous cell carcinoma, which frequently invades the maxilla or the mandible. However, the effects of a mTOR inhibitor on bone destruction associated with oral squamous cell carcinoma are still unclear. In this study, we investigated the antitumor effect of temsirolimus-mediated mTOR inhibition against advanced oral squamous cell carcinoma. Temsirolimus inhibited the proliferation and migration of HSC-2 oral squamous cell carcinoma cells in vitro and suppressed the growth of oral squamous cell carcinoma xenografts in vivo. Significantly, we clearly show that temsirolimus inhibited osteoclast formation both in vitro and in vivo. Reverse transcriptase-PCR analysis showed that temsirolimus decreased the mRNA expression of receptor activator for nuclear factor-κB ligand, known as an osteoclast differentiation factor in bone stromal ST2 cells. Moreover, temsirolimus normalized blood-free calcium concentration in mouse models for humoral hypercalcemia. These findings suggest that mTOR signaling is a potential target of oral squamous cell carcinoma associated with bone destruction, and hence we describe the efficacy of temsirolimus for the treatment of advanced oral squamous carcinoma.

Topics: Animals; Antineoplastic Agents; Bone Neoplasms; Bone Resorption; Carcinoma, Squamous Cell; Cell Movement; Cells, Cultured; Female; Humans; Mice; Mice, Inbred BALB C; Mice, Nude; Mouth Neoplasms; Osteoclasts; Sirolimus; Xenograft Model Antitumor Assays

Despite recent improvements in therapeutic management of osteosarcoma, ongoing challenges in improving the response to chemotherapy warrants new strategies still needed to improve overall patient survival. In this study, we investigated in vivo the effects of RAD001 (Everolimus), a new orally available mTOR inhibitor, on the growth of human and mouse osteosarcoma cells either alone or in combination with zoledronate (ZOL), an anti-osteoporotic drug used to treat bone metastases. RAD001 inhibited osteosarcoma cell proliferation in a dose- and time-dependent manner with no modification of cell-cycle distribution. Combination with ZOL augmented this inhibition of cell proliferation, decreasing PI3K/mTOR signaling compared with single treatments. Notably, in contrast to RAD001, ZOL downregulated isoprenylated membrane-bound Ras concomitantly with an increase of nonisoprenylated cytosolic Ras in sensitive and resistant osteosarcoma cell lines to both drugs. Moreover, ZOL and RAD001 synergized to decrease Ras isoprenylation and GTP-bound Ras levels. Further, the drug combination reduced tumor development in two murine models of osteoblastic or osteolytic osteosarcoma. We found that ZOL could reverse RAD001 resistance in osteosarcoma, limiting osteosarcoma cell growth in combination with RAD001. Our findings rationalize further study of the applications of mTOR and mevalonate pathway inhibitors that can limit protein prenylation pathways.

Topics: Animals; Bone Density Conservation Agents; Bone Neoplasms; Cell Growth Processes; Cell Line, Tumor; Diphosphonates; Drug Resistance, Neoplasm; Drug Synergism; Everolimus; Humans; Imidazoles; Male; Mice; Mice, Inbred C3H; Mice, Inbred C57BL; Osteosarcoma; Protein Prenylation; ras Proteins; Rats; Sirolimus; TOR Serine-Threonine Kinases; Zoledronic Acid

Osteosarcoma is highly resistant to current chemotherapy regimens. Novel therapeutic approaches, potentially involving targeting of specific survival pathways, are needed. We used 17-AAG to inhibit Hsp90 and rapamycin to inhibit mTOR, in the osteosarcoma cell lines, HOS and KHOS/NP. HOS and KHOS cells were treated for 24 and 48 h with 17-AAG or rapamycin and studied drug-induced apoptosis, cell cycle, mitochondrial membrane potential and levels of reduced glutathione (GSH), dephosphorylation of signal transduction proteins in the Akt/MAP kinase pathway and mTOR signaling. 17-AAG was a potent inducer of apoptosis, involving effective depletion of GSH and mitochondrial membrane (MM) depolarization, strong activation of caspase-8 and -9 and release of AIF from mitochondria to the cytosol. Furthermore, 17-AAG down-regulated pAkt, p44Erk, p-mTOR, p70S6, TSC1/2 and pGSK-3beta. Treatment with 17-AAG also caused down-regulation of cyclin D1, GADD45a, GADD34 and pCdc2 and upregulation of cyclin B1 and mitotic block. A decrease in Hsp90 and increase in Hsp70 and Hsp70 C-terminal fragments were also observed. Rapamycin was a less potent inducer of apoptosis, involving a small decrease in GSH and MM potential with no activation of caspases or release of AIF. Rapamycin strongly inhibited cell growth with an increase in G1 and a decrease in S-phase of the cell cycle concomitant with down-regulation of cyclin D1. Rapamycin also down-regulated the activity of p70S6, pAkt and p-mTOR, but had no effect on pGSK-3beta, p44Erk, pCdc2, TSC1/2 or Hsp70 or Hsp90. We conclude that Hsp90 inhibition merits further study in the therapy of osteosarcoma.

Topics: Antibiotics, Antineoplastic; Apoptosis; Benzoquinones; Bone Neoplasms; Cell Cycle; Cell Line, Tumor; Cell Survival; Humans; Lactams, Macrocyclic; Mitochondrial Membranes; Osteosarcoma; Protein Kinases; Protein Serine-Threonine Kinases; Proto-Oncogene Proteins c-akt; Sirolimus; TOR Serine-Threonine Kinases

Signaling through the type 1 insulin-like growth factor receptor (IGF-1R) occurs in many human cancers, including childhood sarcomas. As a consequence, targeting the IGF-1R has become a focus for cancer drug development. We examined the antitumor activity of CP-751,871, a human antibody that blocks IGF-1R ligand binding, alone and in combination with rapamycin against sarcoma cell lines in vitro and xenograft models in vivo. In Ewing sarcoma (EWS) cell lines, CP751,871 inhibited growth poorly (<50%), but prevented rapamycin-induced hyperphosphorylation of AKT(Ser473) and induced greater than additive apoptosis. Rapamycin treatment also increased secretion of IGF-1 resulting in phosphorylation of IGF-1R (Tyr1131) that was blocked by CP751,871. In vivo CP-751,871, rapamycin, or the combination were evaluated against EWS, osteosarcoma, and rhabdomyosarcoma xenografts. CP751871 induced significant growth inhibition [EFS(T/C) >2] in four models. Rapamycin induced significant growth inhibition [EFS(T/C) >2] in nine models. Although neither agent given alone caused tumor regressions, in combination, these agents had greater than additive activity against 5 of 13 xenografts and induced complete remissions in one model each of rhabdomyosarcoma and EWS, and in three of four osteosarcoma models. CP751,871 caused complete IGF-1R down-regulation, suppression of AKT phosphorylation, and dramatically suppressed tumor-derived vascular endothelial growth factor (VEGF) in some sarcoma xenografts. Rapamycin treatment did not markedly suppress VEGF in tumors and synergized only in tumor lines where VEGF was dramatically inhibited by CP751,871. These data suggest a model in which blockade of IGF-1R suppresses tumor-derived VEGF to a level where rapamycin can effectively suppress the response in vascular endothelial cells.

Topics: Animals; Antibodies, Monoclonal; Antineoplastic Combined Chemotherapy Protocols; Bone Neoplasms; Child; Drug Synergism; Female; Humans; Immunoglobulins, Intravenous; Mechanistic Target of Rapamycin Complex 1; Mice; Mice, SCID; Multiprotein Complexes; Osteosarcoma; Proteins; Receptor, IGF Type 1; Rhabdomyosarcoma; Sarcoma; Sarcoma, Ewing; Sirolimus; TOR Serine-Threonine Kinases; Transcription Factors; Vascular Endothelial Growth Factor A

Myxoid chondrosarcoma is a slow-growing sarcoma poorly responsive to chemotherapy and radiation therapy. Translational research has validated several proteins as optional therapeutic targets. Significant responses are, however, rare. In this paper we report an extraordinary response of myxoid chondrosarcoma to targeted therapy by rapamycin in combination with cyclophosphamide. Our case points to a possible novel therapeutic approach towards myxoid chondrosarcoma, by targeting the mammalian target of rapamycin protein, and probably protein kinase C-alpha, mitogen-activated protein kinase, and Jun N-terminal kinase too, by rapamycin.

Topics: Antineoplastic Combined Chemotherapy Protocols; Bone Neoplasms; Chondrosarcoma; Cyclophosphamide; Female; Humans; Middle Aged; Protein Kinases; Sirolimus; TOR Serine-Threonine Kinases

mTOR activity is increased in advanced prostate cancer (CaP) as a result of a high rate of PTEN mutations. RAD001 (Everolimus) is a new orally available mTOR inhibitor. The objective of our study was to evaluate the effects of RAD001 on the growth of CaP in the bone, both alone and in combination with docetaxel and zoledronic acid.. C4-2 CaP cells were injected into tibiae of mice and the animals were treated with RAD001, docetaxel, and zoledronic acid alone or in combination. Histomorphometrical analysis, serum PSA measurements, bone mineral density (BMD), and microCT were used to determine the effects of treatment on tumor and bone.. All three agents alone decreased tumor volume, and RAD001 and docetaxel also decreased levels of serum PSA by 68% and 65%, respectively (both P < 0.01). Combinations of the agents were more effective in decreasing tumor volume than single agents. Three-drug treatment showed the greatest effect: 64% inhibition versus control (P < 0.01). Treatment with RAD001 interfered with the weight loss associated with growth of this tumor in the bone (non-RAD001 groups: 4.0% decrease in body weight, P = 0.0014; RAD001 groups: increase of 3.6% in body weight, P = 0.0037).. RAD001 inhibited growth of C4-2 cells in bone, an effect augmented by addition of docetaxel and zoledronic acid. Moreover RAD001 had a significant impact on maintenance of body weight. RAD001 may hold promise for its effects on both metastatic CaP and the important syndrome of tumor cachexia.

Topics: Animals; Antineoplastic Combined Chemotherapy Protocols; Body Weight; Bone Neoplasms; Cell Line, Tumor; Cell Proliferation; Diphosphonates; Docetaxel; Everolimus; Humans; Imidazoles; Male; Mice; Prostatic Neoplasms; Protein Kinase Inhibitors; Protein Kinases; Sirolimus; Taxoids; Tomography, X-Ray Computed; TOR Serine-Threonine Kinases; Zoledronic Acid

To show the efficacy of targeting EWS/FLI-1 expression with a combination of specific antisense oligonucleotides and rapamycin for the control of Ewing's sarcoma (EWS) cell proliferation in vitro and the treatment of mouse tumor xenografts in vivo.. EWS cells were simultaneously exposed to EWS/FLI-1-specific antisense oligonucleotides and rapamycin for various time periods. After treatment, the following end points were monitored and evaluated: expression levels of the EWS/FLI-1 protein, cell proliferation, cell cycle distribution, apoptotic cell death, caspase activation, and tumor growth in EWS xenografts implanted in nude mice.. Simultaneous exposure of EWS cells in culture to an EWS/FLI-1-targeted suppression therapy using specific antisense oligonucleotides and rapamycin resulted in the activation of a caspase-dependent apoptotic process that involved the restoration of the transforming growth factor-beta-induced proapoptotic pathway. In vivo, individual administration of either antisense oligonucleotides or rapamycin significantly delayed tumor development, and the combined treatment with antisense oligonucleotides and rapamycin caused a considerably stronger inhibition of tumor growth.. Concurrent administration of EWS/FLI-1 antisense oligonucleotides and rapamycin efficiently induced the apoptotic death of EWS cells in culture through a process involving transforming growth factor-beta. In vivo experiments conclusively showed that the combined treatment with antisense oligonucleotides and rapamycin caused a significant inhibition of tumor growth in mice. These results provide proof of principle for further exploration of the potential of this combined therapeutic modality as a novel strategy for the treatment of tumors of the Ewing's sarcoma family.

Topics: Animals; Antibiotics, Antineoplastic; Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Bone Neoplasms; Caspase 3; Caspase 7; Cell Proliferation; Combined Modality Therapy; Dose-Response Relationship, Drug; Gene Targeting; Genetic Therapy; Humans; Male; Mice; Mice, Nude; Oligonucleotides, Antisense; Oncogene Proteins, Fusion; Proto-Oncogene Protein c-fli-1; RNA-Binding Protein EWS; Sarcoma, Ewing; Sirolimus; Transcription Factors; Transforming Growth Factor beta1; Tumor Cells, Cultured; Xenograft Model Antitumor Assays

Osteosarcoma is the most frequent primary malignant tumor of bone with a high propensity for metastasis. We have previously showed that ezrin expression is necessary for metastatic behavior in a murine model of osteosarcoma (K7M2). In this study, we found that a mechanism of ezrin-related metastatic behavior is linked to an Akt-dependent mammalian target of rapamycin (mTOR)/p70 ribosomal protein S6 kinase (S6K1)/eukaryotic initiation factor 4E-binding protein 1 (4E-BP1) pathway. Suppression of ezrin expression either by antisense transfection or by small interfering RNAs or disruption of ezrin function by transfection of a dominant-negative ezrin-T567A mutant led to decreased expression and decreased phosphorylation of both S6K1 and 4E-BP1. Proteosomal inhibition by MG132 reversed antisense-mediated decrease of S6K1 and 4E-BP1 protein expression, but failed to affect the effect of ezrin on phosphorylation of S6K1 and 4E-BP1. Blockade of the mTOR pathway with rapamycin or its analog, cell cycle inhibitor-779 led to significant inhibition of experimental lung metastasis in vivo. These results suggest that blocking the mTOR/S6K1/4E-BP1 pathway may be an appropriate target for strategies to reduce tumor cell metastasis.

Topics: Adaptor Proteins, Signal Transducing; Animals; Bone Neoplasms; Carrier Proteins; Cell Cycle Proteins; Cytoskeletal Proteins; Eukaryotic Initiation Factors; Female; Mice; Mice, SCID; Osteosarcoma; Phosphoproteins; Phosphorylation; Protein Serine-Threonine Kinases; Proto-Oncogene Proteins; Proto-Oncogene Proteins c-akt; Ribosomal Protein S6 Kinases, 70-kDa; RNA, Antisense; RNA, Small Interfering; Sirolimus; Transfection