Project description:Achieved biospecimens annotated with patient clinical characteristics are unique resources for translational research. However, RNA extracted from the achieved tissues is often degraded. RNA degradation can have a significant impact on the measure of transcript abundance that can lead to an increase rate of erroneous differentially expressed genes. Here, we are presenting the transcript integrity number (TIN) algorithm to measure the RNA degradation at transcript level. When applied to RNA-seq datasets generated from human brain Glioblastome cell line, human peripheral blood mononuclear cells, and metastatic castration resistant prostate cancer (mCRPC) clinical tissues, TIN provided a more reliable and more sensitive measure of RNA degradation than RIN, as demonstrated by much higher concordance with the RNA fragment size estimated from read pairs. More importantly, when comparing 10 mCRPC samples with lower RNA quality to another 10 samples with higher RNA quality, we demonstrated that calibrating gene quantification with TIN scores could mitigate RNA degradation effects and greatly improve gene expression analysis. The detected differentially expressed genes before TIN correction were predominantly ribosomal genes. However, when we adjusted gene quantifications with the corresponding TIN scores, we found differentially expressed genes were highly enriched in prostate cancer specific pathways. When further evaluating the performance of TIN correction using synthetic spike-in transcripts with predetermined abundance in RNA-seq data generated from Sequencing Control Consortium (SEQC), we found TIN adjustment had a better control of false positives and false negatives (sensitivity = 0.89, specificity = 0.91), as compared to gene expression analysis results without TIN correction (sensitivity =0.98, specificity = 0.50). RNA sequencing of 20 bone-metastatic castration resistant prostate cancer (mCRPC) using Illumina HiSeq 2500. Out of 20 mCRPC samples, 10 samples have relative low RNA integrity and another 10 samples have relative higher RNA integrity as measured by Agilent RIN score.
Project description:There are many treatment options available for men with metastatic castration-resistant prostate cancer (mCRPC). Yet, biomarkers predictive of differential response to treatment are currently available. A recent translational study suggested that SLCO2B1 genotype could predict response to abiraterone acetate (AA) for men with advanced prostate cancer. Here, we investigate whether germline variants in SLCO2B1 are predictive of response to first-line AA in men with new mCRPC. Clinical data and samples were analyzed from a prospective prostate cancer registry at the University of Utah. Genotyping was performed using the Illumina OmniExpress genotyping platform. Primary endpoint was progression-free survival (PFS) on first-line AA in men with mCRPC. We performed a pre-specified multivariate Cox regression analysis to assess the independent predictive value of rs12422149 and rs1789693 on PFS on AA. Of 401 men with advanced prostate cancer genotyped, 323 were homozygous wild type for rs12422149 (80.5%), 74 were heterozygous (18.5%), and 4 were homozygous variant (1.0%). In a multivariate analysis of 79 men treated with first-line AA for mCRPC, men heterozygous for rs12422149 had significantly improved median PFS compared to the homozygous wild-type group (8.9 months vs. 6.3 months, HR 0.46, 95% CI 0.23-0.94, p=0.03). No significant difference in median PFS was seen by rs1789693 genotype. In this first clinical validation of translational data reported by Mostaghel and colleagues, germline variant alleles in rs12422149 of SLCO2B1 are common and predict improved response to first-line AA In men with mCRPC.
Project description:The widespread and long-term use of potent therapies designed to repress androgen receptor (AR) signaling is changing the molecular and phenotypic landscapes of prostate cancer. We conducted molecular profiling of metastatic castration-resistant prostate cancer (mCRPC) patient specimens and patient-derived xenograft models and identified five distinct mCRPC phenotypes. Herein, we characterize an AR-low phenotype that has low AR expression with concomitant decreases in a subset of AR regulated genes, and an amphicrine phenotype that has both AR and neuroendocrine activity in the same cell. Furthermore, our data highlight an emerging squamous cell mCRPC phenotype.
Project description:Neuroendocrine (NE) differentiation in metastatic castration-resistant prostate cancer (mCRPC) usually develops through cellular plasticity. We recently characterized two mCRPC phenotypes with NE features; Androgen receptor (AR)-positive, NE-positive amphicrine prostate cancer (AMPC) and AR-negative small cell or neuroendocrine prostate cancer (SCNPC). Here, we interrogate the RE-1 silencing transcription factor (REST) pathway in mCRPC and demonstrate that SRRM3 has analogous functions to SRRM4 and mediates NE differentiation through alternative splicing of REST. We scrutinize transcriptome datasets across species and tumor types and discover that SRRM3 and SRRM4 expression define molecular phenotypes in AMPC and SCNPC. Notably, we characterize two AMPC phenotypes driven by either REST attenuation or ASCL1 activity and three SCNPC phenotypes with progressive activation of neuronal transcription factor programs. Together, our data provides a biological framework for classifying NE phenotypes in mCRPC that could be useful for future therapeutic development and precision medicine applications.
Project description:Neuroendocrine (NE) differentiation in metastatic castration-resistant prostate cancer (mCRPC) usually develops through cellular plasticity. We recently characterized two mCRPC phenotypes with NE features; Androgen receptor (AR)-positive, NE-positive amphicrine prostate cancer (AMPC) and AR-negative small cell or neuroendocrine prostate cancer (SCNPC). Here, we interrogate the RE-1 silencing transcription factor (REST) pathway in mCRPC and demonstrate that SRRM3 has analogous functions to SRRM4 and mediates NE differentiation through alternative splicing of REST. We scrutinize transcriptome datasets across species and tumor types and discover that SRRM3 and SRRM4 expression define molecular phenotypes in AMPC and SCNPC. Notably, we characterize two AMPC phenotypes driven by either REST attenuation or ASCL1 activity and three SCNPC phenotypes with progressive activation of neuronal transcription factor programs. Together, our data provides a biological framework for classifying NE phenotypes in mCRPC that could be useful for future therapeutic development and precision medicine applications.
Project description:Metastatic castrate-resistant prostate cancer (mCRPC) is a genetically and phenotypically heterogeneous cancer where advancements are needed in biomarker discovery and targeted therapy. A critical and often effective component of treatment includes taxanes. We performed one of the first high throughput screens across a cohort of 30 diverse patient-derived CRPC organoids to a library of 78 drugs. Combining quantitative response measures with transcriptomic analyses demonstrated that HNF1 Homeobox A (HNF1A) drives a transcriptional program of taxane resistance, dependent upon cellular inhibitor of apoptosis protein 2 (cIAP2). Monotherapy with cIAP2 inhibitor LCL161 was sufficient to treat HNF1A+ models of mCRPC previously resistant to docetaxel.
Project description:Aim: We examined methylation changes in cell-free DNA (cfDNA) in metastatic castration resistant prostate cancer (mCRPC) during treatment. Patients and Methods: Genome-wide methylation analysis of sequentially collected cfDNA samples derived from mCRPC patients undergoing androgen-targeting therapy was performed. Results: Alterations in methylation states of genes previously implicated in prostate cancer progression were observed, and patients that maintained methylation changes throughout therapy tended to have a longer time to clinical progression (TTP). Importantly, we also report that markers associated with a highly aggressive form of the disease, Neuroendocrine-CRPC, were associated with a faster TTP. Conclusion: Our findings highlight the potential of monitoring the cfDNA methylome during therapy in mCRPC, which may serve as predictive markers of response to androgen-targeting agents.