GSE158593
RNA splicing factors SRRM3 and SRRM4 distinguish molecular phenotypes of castration-resistant neuroendocrine prostate cancer [RNA-seq]
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. Overall design: Transcriptome profiling of human prostate tumor cell lines using Illumina TruSeq Library prep sequenced on Illumina NovaSeq and methylation profiling using Illumina Infinium MethylationEPIC BeadChip arrays.