ABSTRACT
Neuroendocrine (NE) prostate cancer (NEPC) is a lethal subtype of castration-resistant prostate cancer (PCa) arising either de novo or from transdifferentiated prostate adenocarcinoma following androgen deprivation therapy (ADT). Extensive computational analysis has identified a high degree of association between the long noncoding RNA (lncRNA) H19 and NEPC, with the longest isoform highly expressed in NEPC. H19 regulates PCa lineage plasticity by driving a bidirectional cell identity of NE phenotype (H19 overexpression) or luminal phenotype (H19 knockdown). It contributes to treatment resistance, with the knockdown of H19 re-sensitizing PCa to ADT. It is also essential for the proliferation and invasion of NEPC. H19 levels are negatively regulated by androgen signaling via androgen receptor (AR). When androgen is absent SOX2 levels increase, driving H19 transcription and facilitating transdifferentiation. H19 facilitates the PRC2 complex in regulating methylation changes at H3K27me3/H3K4me3 histone sites of AR-driven and NEPC-related genes. Additionally, this lncRNA induces alterations in genome-wide DNA methylation on CpG sites, further regulating genes associated with the NEPC phenotype. Our clinical data identify H19 as a candidate diagnostic marker and predictive marker of NEPC with elevated H19 levels associated with an increased probability of biochemical recurrence and metastatic disease in patients receiving ADT. Here we report H19 as an early upstream regulator of cell fate, plasticity, and treatment resistance in NEPC that can reverse/transform cells to a treatable form of PCa once therapeutically deactivated.
Subject(s)
Carcinoma, Neuroendocrine/genetics , Carcinoma, Neuroendocrine/pathology , Cell Plasticity/genetics , Gene Expression Regulation, Neoplastic , Prostatic Neoplasms/genetics , Prostatic Neoplasms/pathology , RNA, Long Noncoding/metabolism , Androgen Antagonists/therapeutic use , Animals , Benzamides/pharmacology , Benzamides/therapeutic use , Biomarkers, Tumor/metabolism , Carcinoma, Neuroendocrine/diagnosis , Carcinoma, Neuroendocrine/drug therapy , Cell Line, Tumor , Cell Lineage/genetics , Cell Nucleus/metabolism , Cell Proliferation/genetics , Cohort Studies , DNA Methylation/genetics , Disease Models, Animal , Drug Resistance, Neoplasm/genetics , Epigenesis, Genetic/drug effects , Genome, Human , Histones/metabolism , Humans , Male , Neoplasm Grading , Neoplasm Invasiveness , Neoplastic Stem Cells/metabolism , Nitriles/pharmacology , Nitriles/therapeutic use , Organoids/metabolism , Organoids/pathology , Phenylthiohydantoin/pharmacology , Phenylthiohydantoin/therapeutic use , Phylogeny , Polycomb Repressive Complex 2/metabolism , Promoter Regions, Genetic/genetics , Prostatic Neoplasms/diagnosis , Prostatic Neoplasms/drug therapy , Protein Isoforms/genetics , Protein Isoforms/metabolism , RNA, Long Noncoding/genetics , Receptors, Androgen/metabolism , SOXB1 Transcription Factors/metabolism , Transcription, Genetic/drug effectsABSTRACT
AIM: Development of a sensitive method for DNA methylation profiling and associated mutation detection in clinical samples. MATERIALS & METHODS: Formalin-fixed and paraffin-embedded tumors received by clinical laboratories often contain insufficient DNA for analysis with bisulfite or methylation sensitive restriction enzymes-based methods. To increase sensitivity, methyl-CpG DNA capture and Coupled Abscription PCR Signaling detection were combined in a new assay, MethylMeter(®). Gliomas were analyzed for MGMT methylation, glioma CpG island methylator phenotype and IDH1 R132H. RESULTS: MethylMeter had 100% assay success rate measuring all five biomarkers in formalin-fixed and paraffin-embedded tissue. MGMT methylation results were supported by survival and mRNA expression data. CONCLUSION: MethylMeter is a sensitive and quantitative method for multitarget DNA methylation profiling and associated mutation detection. The MethylMeter-based GliomaSTRAT assay measures methylation of four targets and one mutation to simultaneously grade gliomas and predict their response to temozolomide. This information is clinically valuable in management of gliomas.
