Project description:Castration resistant prostate cancer (CRPC) develops resistance to antiandrogens affecting Androgen Receptor (AR) signaling through a variety of mechanism. Because of this, the efficacy of androgen receptor targeted therapy remains limited for many patients with CRPC. We developed C42B-Abiraterone (Abi) and resistance cells to study changes in transcriptomic profile compared to parental cells.
Project description:To identify the molecular signature associated with abiraterone acetate (AA) response and mechanisms underlying AA resistance in castration-resistant prostate cancer patient-derived xenografts (PDXs).
Project description:Here, we analyze gene expression of prostate cancer cell line VCaP (VCaP WT) and VCaP after long time treatment with abiraterone (VCaP AA) in order to investigate possible resistance mechanisms to second-generation antiandrogens.
Project description:Purpose: Primary resistance to abiraterone acetate (AA), a key medication for the treatment of metastatic castration-resistant prostate cancer, occurs in 20-40% of the patients. We aim to identify predictive biomarkers for AA-treatment response and understand the mechanisms related to treatment resistance. Experimental Design: We used the Infinium Human Methylation 450K BeadChip to monitor modification profiles of cell-free circulating DNA (cfDNA) in 108 plasma samples collected from 33 AA-treated patients. Results: Thirty cytosines showed significant modification differences (FDR q < 0.05) between the AA-sensitive and AA-resistant patients during the treatment, of which 21 cytosines were differentially modified prior to treatment. In addition, the AA-sensitive patients, but not AA-resistant patients, lost interindividual variation of cfDNA modification shortly after starting AA-treatment, but such variation returned to initial levels in the later phases of treatment. Conclusions: Our findings provide a list of potential biomarkers for prediction of AA-treatment response, highlight the prognostic value of using cytosine modification variance as biomarkers, and shed new insights into the mechanisms of prostate cancer relapse in AA-sensitive patients.
Project description:We report RNA sequencing data on serial biopsies of prostate cancer VCaP xenografts as the tumors pass from androgen-sensitivity (Pre-Cx), to castration resistance (CRPC, castration resistant prostate cancer), onto resistance to dual therapy with abiraterone plus enzalutamide (AER). From comparison of these RNAseq data sets, we were able to determine differentially expressed genes between the AER/CRPC and Pre-Cx states that could mediate resistance to androgen deprivation therapies.
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:Background: Abiraterone (Abi) is an androgen receptor signaling inhibitor that significantly improves patients' life expectancy in metastatic prostate cancer (PCa). Despite its beneficial effects, many patients have baseline or acquired resistance against Abi. Objective: To identify predictive serum biomarkers for Abi treatment. Design, setting, and participants: We performed a comparative proteome analysis on three Abi sensitive (LNCaPabl, LAPC4, DuCaP) and resistant (LNCaPabl-Abi, LAPC4-Abi, DuCaP-Abi) PCa cell lines using liquid chromatography tandem mass spectrometry (LC-MS/MS) technique. Two bioinformatic selection methods were applied to select the most promising candidate serum markers. Serum levels of selected proteins were assessed in samples of 100 Abi-treated patients with metastatic castration-resistant disease using ELISA. Moreover, FSCN1 serum concentrations were measured in samples of 69 Docetaxel (Doc) treated mCRPC patients. Outcome measurements and statistical analysis: Serum levels were correlated with patients‘ clinicopathological parameters and survival. Results and limitations: Our proteome analysis identified 68 significantly, at least two-fold upregulated proteins in Abi resistant cells. Using two filtering methods four proteins (AMACR, KLK2, FSCN1 and CTAG1A) were selected for ELISA analyses. We found high baseline FSCN1 serum levels to be significantly associated with poor survival in Abi-treated mCRPC patients. Moreover, the multivariable analysis revealed that higher ECOG status (>1) and high baseline FSCN1 serum levels (>10.22 ng/ml by ROC cut-off) were independently associated with worse survival in Abi-treated patients (p<0.001 and p=0.021, respectively). In contrast, no association was found between serum FSCN1 concentrations and overall survival in Doc-treated patients. Conclusions: Our analysis identified baseline FSCN1 serum levels to be independently associated with poor survival of Abi-treated, but not Doc-treated mCRPC patients, suggesting a therapy specific prognostic value for FSCN1. Patient summary: In this study, we identified serum FSCN1 as a marker that may help to predict PCa patients who derive less benefit from Abi but not Doc treatment.