RESUMO
Androgen receptor (AR) signaling is the central driver of prostate cancer across disease states. While androgen deprivation therapy (ADT) is effective in the initial treatment of prostate cancer, resistance to ADT or to next-generation androgen pathway inhibitors invariably arises, most commonly through the re-activation of the AR axis. Thus, orthogonal approaches to inhibit AR signaling in advanced prostate cancer are essential. Here, via genome-scale CRISPR-Cas9 screening, we identify protein arginine methyltransferase 1 (PRMT1) as a critical mediator of AR expression and signaling. PRMT1 regulates the recruitment of AR to genomic target sites and the inhibition of PRMT1 impairs AR binding at lineage-specific enhancers, leading to decreased expression of key oncogenes, including AR itself. In addition, AR-driven prostate cancer cells are uniquely susceptible to combined AR and PRMT1 inhibition. Our findings implicate PRMT1 as a key regulator of AR output and provide a preclinical framework for co-targeting of AR and PRMT1 in advanced prostate cancer.
Assuntos
Neoplasias de Próstata Resistentes à Castração , Neoplasias da Próstata , Antagonistas de Androgênios/farmacologia , Antagonistas de Androgênios/uso terapêutico , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Próstata/metabolismo , Neoplasias da Próstata/metabolismo , Neoplasias de Próstata Resistentes à Castração/genética , Proteína-Arginina N-Metiltransferases/genética , Proteína-Arginina N-Metiltransferases/metabolismo , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Proteínas Repressoras/metabolismo , Transdução de SinaisRESUMO
Translocation renal cell carcinoma (tRCC) is a poorly characterized subtype of kidney cancer driven by MiT/TFE gene fusions. Here, we define the landmarks of tRCC through an integrative analysis of 152 patients with tRCC identified across genomic, clinical trial, and retrospective cohorts. Most tRCCs harbor few somatic alterations apart from MiT/TFE fusions and homozygous deletions at chromosome 9p21.3 (19.2% of cases). Transcriptionally, tRCCs display a heightened NRF2-driven antioxidant response that is associated with resistance to targeted therapies. Consistently, we find that outcomes for patients with tRCC treated with vascular endothelial growth factor receptor inhibitors (VEGFR-TKIs) are worse than those treated with immune checkpoint inhibitors (ICI). Using multiparametric immunofluorescence, we find that the tumors are infiltrated with CD8+ T cells, though the T cells harbor an exhaustion immunophenotype distinct from that of clear cell RCC. Our findings comprehensively define the clinical and molecular features of tRCC and may inspire new therapeutic hypotheses.
Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Carcinoma de Células Renais/genética , Neoplasias Renais/genética , Fator de Transcrição Associado à Microftalmia/genética , Proteínas de Fusão Oncogênica/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Linfócitos T CD8-Positivos/imunologia , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/patologia , Regulação Neoplásica da Expressão Gênica , Fusão Gênica/genética , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/patologia , Proteínas de Fusão Oncogênica/metabolismo , Inibidores de Proteínas Quinases/uso terapêutico , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidoresRESUMO
Tuberous Sclerosis Complex (TSC) is caused by TSC1 or TSC2 mutations, resulting in hyperactivation of the mechanistic target of rapamycin complex 1 (mTORC1). Transcription factor EB (TFEB), a master regulator of lysosome biogenesis, is negatively regulated by mTORC1 through a RAG GTPase-dependent phosphorylation. Here we show that lysosomal biogenesis is increased in TSC-associated renal tumors, pulmonary lymphangioleiomyomatosis, kidneys from Tsc2+/- mice, and TSC1/2-deficient cells via a TFEB-dependent mechanism. Interestingly, in TSC1/2-deficient cells, TFEB is hypo-phosphorylated at mTORC1-dependent sites, indicating that mTORC1 is unable to phosphorylate TFEB in the absence of the TSC1/2 complex. Importantly, overexpression of folliculin (FLCN), a GTPase activating protein for RAGC, increases TFEB phosphorylation at the mTORC1 sites in TSC2-deficient cells. Overexpression of constitutively active RAGC is sufficient to relocalize TFEB to the cytoplasm. These findings establish the TSC proteins as critical regulators of lysosomal biogenesis via TFEB and RAGC and identify TFEB as a driver of the proliferation of TSC2-deficient cells.
