Project description:Cdk4/6 inhibitors have shown to increase overall survival in hormone-positive breast tumors, but whether other solid tumors could respond to these inhibitors has not yet defined. Here we show that Palbociclib (a Cdk4/6 specific inhibitor in clinic use) treatment exerts antiproliferative effects in vivo using a bladder cancer cell lines.
Project description:Cdk4/6 inhibitors have shown to increase overall survival in hormone-positive breast tumors, but whether other solid tumors could respond to these inhibitors has not yet defined. Here we show that Palbociclib (a Cdk4/6 specific inhibitor in clinic use) + cisplatin (CDDP, a chemotherapeutic agent most active in locally or advanced bladder cancer patients) treatment exerts antiproliferative effects in vivo using a bladder cancer mouse model.
Project description:We prepared five RASF samples from each donor under four conditions: in the presence or absence of CDK4/6 inhibitor, palbociclib, and with or without cytokine stimulations. In total, 20 samples were analyzed. RASFs were treated with CDK4/6 inhibitor for 24 hours in advance to the stimulation. RNA was collected after 24 hours of the stimulation(TNF+IL-1b, 0.2ng/ml each)
Project description:CDK4/6 kinase inhibitors have shown great promise in clinical trials in various cancer types and have recently entered clinical trial for advanced prostate cancer. Although patients are expected to respond well to this class of drugs, development of resistance in some patients is anticipated. To pre-empt this and study how prostate cancer may evade CDK4/6 inhibition, new resistance models were generated from LNCaP and LAPC4 prostate cancer cells cells by prolonged culturing in presence of 0.5uM palbociclib. A shotgun phosphoproteomics approach was utilized and integrated with RNA sequencing data to unravel the molecular underpinnings of acquired resistance to palbociclib and resultant broad CDK4/6 inhibitor resistance.
Project description:We evaluated the tumor efficacy of the CDK4/6 inhibitor palbociclib in two chordoma Patient’s Derived Xenograft (PDX) models to validate and identify novel therapeutic approaches.
Project description:PURPOSE: Despite over 70,000 new cases of bladder cancer in the United States annually, patients with advanced disease have a poor prognosis due to limited treatment modalities. We evaluate the role of Aurora A, identified as an upregulated candidate molecule in bladder cancer, in regulating bladder tumor growth. EXPERIMENTAL DESIGN: Gene expression in human bladder cancer samples was evaluated using RNA microarray and reverse-transcriptase PCR. The specific Aurora kinase A inhibitor MLN8237 (Millennium) was used to determine effects on bladder cancer cell growth using in vitro and in vivo models using malignant T24 and UM-UC-3 and papilloma-derived RT4 bladder cells. RESULTS: Urothelial carcinoma upregulates a set of 13 mitotic spindle associated transcripts, as compared to normal urothelium, including MAD2L1 (7.6-fold), BUB1B (8.8-fold), Aurora kinases A (5.6-fold) and Aurora kinase B (6.2-fold). Application of MLN8237 (10nM-1µM) to the human bladder tumor cell lines T24 and UM-UC-3 induced dose-dependent G2 cell cycle arrest, aneuploidy, mitotic spindle abnormalities, and apoptosis. MLN8237 arrested tumor growth when administered orally over 4 weeks in a mouse bladder cancer xenograft model (p<0.05). Finally, in vitro combination of MLN8237 with either paclitaxel or gemcitabine produced schedule-dependent synergistic antiproliferative effects in T24 cells when administered sequentially. CONCLUSIONS: Mitotic spindle checkpoint dysfunction is a common characteristic of human urothelial carcinoma, and can be exploited with pharmacologic Aurora A inhibition. Future studies that explore the mechanisms of spindle checkpoint failure in bladder cancer and evaluate the therapeutic role of Aurora kinases for bladder cancer patients would be of value. Tissue samples with urothelial cell carcinoma from bladder as well as normal references were collected and the gene expression profiles were compared. No technical replicates.
Project description:CDK4/6 kinase inhibitors have shown great promise in clinical trials in various cancer types and have recently entered clinical trial for advanced prostate cancer. Although patients are expected to respond well to this class of drugs, development of resistance in some patients is anticipated. To pre-empt this and study how prostate cancer may evade CDK4/6 inhibition, new resistance models were generated from LNCaP and LAPC4 prostate cancer cells cells by prolonged culturing in presence of 0.5uM palbociclib. RNA sequencing data was integrated with phospho-proteomics to unravel the molecular underpinnings of acquired resistance to palbociclib and resultant broad CDK4/6 inhibitor resistance.
Project description:In this study, we found that combination treatment of breast cells with CK1 inihbitor (D 4476) and CDK4/6 inhibitor (Ribociclib) exhibited greatly enhanced therapeutic efficacy than CDK4/6 inhiitor single treatment
Project description:Continuous MEK and CDK4/6 inhibition is effective in pre-clinical models, nevertheless, some tumors acquire resistance that was associated with enhanced phospho S6. To characterize the mechanism mediating the upregulation of mTOR-S6 pathway in these tumors, we performed RNA sequencing and targeted panel sequencing on xenograft tumors that progressed on either MEK plus CDK4/6 inhibitors (ComboR) or control diet. Gene set variance analysis (GSVA) revealed distinct gene expression signatures between the two ComboR tumors indicating heterogeneity. However, one of the 44 shared pathways between ComboR1 and ComboR2 included upregulation of an AKT pathway gene signature. By targeted sequencing and RNA sequencing, we observed high copy number change of NRAS in ComboR1 and a third tumor sample isolated from a continuous MEK inhibitor-intermittent CDK4/6 inhibitor schedule. NRAS was confirmed to mediate increased mTOR-S6 pathway activation suggesting that while distinct mechanisms are employed by melanoma tumors to circumvent MEK plus CDK4/6 inhibition, those resistance pathways eventually converge upon phosphorylation of S6 protein.
Project description:CDK4/6 inhibitor (CDK4/6i) resistance is a pressing clinical problem for patients with ER+ breast cancer. Previous work identified CDK6 overexpression as one critical determinant of acquired resistance to CDK4/6 inhibition. This dataset interrogates CDK6 interactors/recruiters to determine their role in transcriptional regulation of CDK4/6i resistance mechanisms and will provide novel therapeutic strategies to overcome resistance.