ganetespib

Therapeutic effects of photodynamic therapy (PDT) are limited by the selectivity of photosensitizer (PS). Herein, a novel tumor-targeted drug-PS conjugate (Gan-ZnPc) which integrated with zinc phthalocyanine (ZnPc) and Ganetespib has been developed. ZnPc is a promising PS with remarkable photosensitization ability. Ganetespib is a heat shock protein 90 (Hsp90) inhibitor with preferential tumor selectivity and conjugated to ZnPc as a tumor-targeted ligand. The multifunctional small molecule conjugate, Gan-ZnPc, could be bound to extracellular Hsp90 and then selectively internalized into the tumor cells, followed by the generation of abundant intracellular reactive oxygen species (ROS) upon irradiation...

Introduction: Small cell lung cancer (SCLC) accounts for 15% of all lung cancers and is characterized by high response rates to cytotoxic chemotherapy and equally high rates of relapse. Many resistance mechanisms have been proposed including resistance to doxorubicin via induction of a heat shock response. Ganetespib is a novel and potent non-geldanamycin heat shock protein 90 (Hsp90) inhibitor. In preclinical studies, synergy between ganetespib and doxorubicin was shown. We conducted a phase Ib/II study of the safety, tolerability, and preliminary efficacy of the combination of ganetespib and doxorubicin...

Tanshinone IIA (Tan IIA), the primary bioactive compound derived from the traditional Chinese medicine (TCM) Salvia miltiorrhiza Bunge, has been reported to possess antitumor activity. However, its antitumor mechanisms are not fully understood. To resolve the potential antitumor mechanism(s) of Tan IIA, its gene expression profiles from our database was analyzed by connectivity map (CMAP) and the CMAP-based mechanistic predictions were confirmed/validated in further studies. Specifically, Tan IIA inhibited total protein kinase C (PKC) activity and selectively suppressed the expression of cytosolic and plasma membrane PKC isoforms ζ and ε...

Autosomal-dominant polycystic kidney disease (ADPKD) is associated with progressive formation of renal cysts, kidney enlargement, hypertension, and typically end-stage renal disease. In ADPKD, inherited mutations disrupt function of the polycystins (encoded by PKD1 and PKD2), thus causing loss of a cyst-repressive signal emanating from the renal cilium. Genetic studies have suggested ciliary maintenance is essential for ADPKD pathogenesis. Heat shock protein 90 (HSP90) clients include multiple proteins linked to ciliary maintenance...

Hyperthermia - application of supra-physiological temperatures to cells, tissues or organs - is a pleiotropic treatment that affects most aspects of cellular metabolism, but its effects on DNA are of special interest in the context of cancer research and treatment. Hyperthermia inhibits repair of various DNA lesions, including double-strand breaks (DSBs), making it a powerful radio- and chemosensitizer, with proven clinical efficacy in therapy of various types of cancer, including tumors of head and neck, bladder, breast and cervix...

Prostate cancer (PCa) cells expressing full-length androgen receptor (AR-FL) are susceptible to androgen deprivation therapy (ADT). However, outgrowth of castration-resistant prostate cancer (CRPC) can occur due to the expression of constitutively active (ligand-independent) AR splice variants, particularly AR-V7. We previously demonstrated that sulforaphane (SFN), an isothiocyanate phytochemical, can decrease AR-FL levels in the PCa cell lines, LNCaP and C4-2B. Here, we examined the efficacy of SFN in targeting both AR-FL and AR-V7 in the CRPC cell line, CWR22Rv1 (22Rv1)...

T-cell-based immunotherapies are promising treatments for cancer patients. Although durable responses can be achieved in some patients, many patients fail to respond to these therapies, underscoring the need for improvement with combination therapies. From a screen of 850 bioactive compounds, we identify HSP90 inhibitors as candidates for combination with immunotherapy. We show that inhibition of HSP90 with ganetespib enhances T-cell-mediated killing of patient-derived human melanoma cells by their autologous T cells in vitro and potentiates responses to anti-CTLA4 and anti-PD1 therapy in vivo...

BACKGROUND: Heat shock protein 90 (HSP90) and the ubiquitin-proteasome pathway play crucial roles in the homeostasis of pancreatic cancer cells. This study combined for the first time the HSP90 inhibitor ganetespib (Gan) and the proteasome inhibitor carfilzomib (Carf) to target key mechanisms of homeostasis in pancreatic cancer. It was hypothesized that Gan plus Carf would elicit potent antitumor activity by modulating complementary homeostatic processes. METHODS: In vitro and in vivo effects of this combination on mechanisms of cell growth and viability were evaluated with human pancreatic cancer cell lines (MIA PaCa-2 and HPAC)...

Gastric cancer exhibits a poor prognosis and is the third most common cause of cancer death worldwide. Chemotherapy of metastatic gastric cancer is based on combinations of platinum drugs and fluoropyrimidines, with added agents. Oxoplatin is a stable oral platinum(IV) prodrug which is converted to a highly active tetrachlorido(IV) complex under acidic conditions. In the present work, we studied the cytotoxic effects of oxoplatin against a panel of four gastric cancer cell lines in vitro. Furthermore, the role of HSP90 in chemoresistance of these lines was investigated using the specific inhibitor ganetespib...

BACKGROUND: Targeted therapies in HER2-positive metastatic breast cancer significantly improve outcomes but efficacy is limited by therapeutic resistance. HER2 is an acutely sensitive Heat Shock Protein 90 (HSP90) client and HSP90 inhibition can overcome trastuzumab resistance. Preclinical data suggest that HSP90 inhibition is synergistic with taxanes with the potential for significant clinical activity. We therefore tested ganetespib, a HSP90 inhibitor, in combination with paclitaxel and trastuzumab in patients with trastuzumab-refractory HER2-positive metastatic breast cancer...

Two missense mutations of the DYRK1B gene have recently been found to co-segregate with a rare autosomal-dominant form of metabolic syndrome. This gene encodes a member of the DYRK family of protein kinases, which depend on tyrosine autophosphorylation to acquire the catalytically active conformation. The mutations (H90P and R102C) affect a structural element named DYRK homology (DH) box and did not directly interfere with the conformation of the catalytic domain in a structural model of DYRK1B. Cellular assays showed that the mutations did not alter the specific activity of mature kinase molecules...

Heat shock protein 90 (HSP90) regulates several important cellular processes via its repertoire of 'client proteins'. These client proteins have been found to play fundamental roles in signal transduction, cell proliferation, cell cycle progression and survival, as well as other features of malignant cells, such as invasion, tumor angiogenesis and metastasis. Thus, HSP90 is an emerging target for cancer therapy. To this end, we evaluated ganetespib (STA-9090), a novel and potent HSP90 inhibitor, for its activity in gastric cancer cell lines...

Sunitinib malate (sunitinib) is an orally available, multitargeted tyrosine kinase inhibitor with antitumor and antiangiogenic activities. Although sunitinib is effective for the treatment of patients with gastrointestinal stromal tumor, advanced renal cell carcinoma, or pancreatic neuroendocrine tumor, adverse cardiac events associated with sunitinib administration have been reported. Here, we examined the effect of geldanamycin, an inhibitor of heat shock protein (Hsp) 90, on sunitinib-induced cytotoxicity in cardiomyocytes...

Silencing of tumor suppressor and DNA repair genes through methylation plays a role in cancer development, growth and response to therapy in colorectal and pancreatic cancers. Heat shock protein 90 (HSP90) regulates transcription of DNA methyltransferase enzymes (DNMT). In addition, DNMTs are client proteins of HSP90. The aim of this study is to evaluate the effects of HSP90 inhibition on DNA methylation in colorectal and pancreatic cancer cell lines. Our data shows that inhibition of HSP90 using ganetespib resulted in downregulation of mRNA and protein expression of DNMT1, DNMT3A, and DNMT3B in HT-29 and MIA PaCa-2 cell lines...

A subset of non-small cell lung cancers (NSCLC) are dependent upon oncogenic driver mutations, including the most frequently observed driver mutant KRAS, which is associated with a poor prognosis. As direct RAS targeting in the clinic has been unsuccessful to date, use of Hsp90 inhibitors appeared to be a promising therapy for KRAS-mutant NSCLC; however, limited clinical efficacy was observed due to rapid resistance. Furthermore, the combination of the Hsp90 inhibitor (Hsp90i), ganetespib, and docetaxel was tested in a phase III clinical trial and failed to demonstrate benefit...

Heat shock protein 90 is a molecular chaperon that maintains the correct folding and function of multiple client proteins. The inhibition of heat shock protein 90, which leads to the simultaneous degradation of multiple proteins involved in oncogenic signaling pathways, has revealed an innovative strategy to treat a variety of cancer types. We evaluated the therapeutic effects of ganetespib, a heat shock protein 90 inhibitor, in treating thyroid cancer. Ganetespib effectively inhibited cell proliferation in a dose-dependent manner in eight cell lines originating from four major histologic types of thyroid cancer (papillary, follicular, anaplastic and medullary)...

OBJECTIVES: Heat shock protein 90 regulates multiple signaling proteins involved in key pathways of pancreatic cancer pathogenesis. Ganetespib binds to heat shock protein 90 and interferes with its binding to client proteins thus leading to inactivation and degradation of the signaling proteins that promote cancer progression. This phase II study was designed to evaluate the efficacy of ganetespib in patients with refractory metastatic pancreatic cancer (rMPC). METHODS: Patients with rMPC received 175 mg/m ganetespib intravenously once weekly for 3 weeks in 4-week cycles...

The DNA-alkylating cytotoxic agent cyclophosphamide (CTX) is commonly used in the clinic to treat hematological malignancies like lymphomas and leukemias as well as solid tumors, but shows dose-dependent potentially life-threatening toxicities and can induce secondary malignancies. Thus, the clinical utility of CTX would be improved if a companion drug could be identified that allows lowering the CTX dose, while maintaining or even increasing its antineoplastic therapeutic efficacy. In mouse models, high-dose CTX (300 mg/kg) is effective in treating T-lymphomas, while low dose (defined here as 100 mg/kg) is ineffective...

Heat shock protein 90 (HSP90) inhibition is an attractive strategy for cancer treatment. Several HSP90 inhibitors have shown promising effects in clinical oncology trials. However, little is known about HSP90 inhibition-mediated bladder cancer therapy. Here, we report a quantitative proteomic study that evaluates alterations in protein expression and histone post-translational modifications (PTMs) in bladder carcinoma in response to HSP90 inhibition. We show that 5 HSP90 inhibitors (AUY922, ganetespib, SNX2112, AT13387, and CUDC305) potently inhibited the proliferation of bladder cancer 5637 cells in a dose- and time-dependent manner...

Cancer cells have a higher need of chaperones than normal cells to prevent the toxic effects of intracellular protein misfolding and aggregation. Heat shock proteins (Hsps) belong to these chaperones; they are classified into families according to molecular size. Hsps are upregulated in many cancers and inhibition can inhibit tumor growth by destabilizing proteins necessary for tumor survival. In non-small cell lung cancer (NSCLC), there are three different Hsp antagonist classes that are in (early) clinical trials: Hsp90, Hsp70 and Hsp27 inhibitors...