RESUMEN
The evolutionarily conserved minor spliceosome (MiS) is required for protein expression of â¼714 minor intron-containing genes (MIGs) crucial for cell-cycle regulation, DNA repair, and MAP-kinase signaling. We explored the role of MIGs and MiS in cancer, taking prostate cancer (PCa) as an exemplar. Both androgen receptor signaling and elevated levels of U6atac, a MiS small nuclear RNA, regulate MiS activity, which is highest in advanced metastatic PCa. siU6atac-mediated MiS inhibition in PCa in vitro model systems resulted in aberrant minor intron splicing leading to cell-cycle G1 arrest. Small interfering RNA knocking down U6atac was â¼50% more efficient in lowering tumor burden in models of advanced therapy-resistant PCa compared with standard antiandrogen therapy. In lethal PCa, siU6atac disrupted the splicing of a crucial lineage dependency factor, the RE1-silencing factor (REST). Taken together, we have nominated MiS as a vulnerability for lethal PCa and potentially other cancers.
Asunto(s)
Neoplasias de la Próstata Resistentes a la Castración , Neoplasias de la Próstata , Masculino , Humanos , Intrones/genética , Neoplasias de la Próstata/metabolismo , Empalme del ARN/genética , Empalmosomas/metabolismo , Transducción de Señal , Receptores Androgénicos/genética , Receptores Androgénicos/metabolismo , Línea Celular Tumoral , Neoplasias de la Próstata Resistentes a la Castración/genéticaRESUMEN
Prostate cancer is one of the most prevalent and, upon metastasis, deadliest cancers in men. Timely identification is essential for effective treatment. Furthermore, accurate determination of prostatic origin is crucial for personalized therapy once the cancer has spread. However, current prostate cancer screening methods are lacking. A recent article in The Journal of Pathology addresses this issue by utilizing an improved antibody to reevaluate HOXB13 as a lineage marker for prostate cancer. The study's findings support the concept that, despite decreased expression in advanced prostate cancer, HOXB13 remains highly suitable for determining prostatic origin due to its androgen receptor independence, high specificity, and sensitivity. © 2024 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.
Asunto(s)
Neoplasias de la Próstata , Masculino , Humanos , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/metabolismo , Antígeno Prostático Específico/metabolismo , Detección Precoz del Cáncer , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Próstata/patología , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , InmunoglobulinasRESUMEN
Advanced prostate cancer initially responds to hormonal treatment, but ultimately becomes resistant and requires more potent therapies. One mechanism of resistance observed in around 10-20% of these patients is lineage plasticity, which manifests in a partial or complete small cell or neuroendocrine prostate cancer (NEPC) phenotype. Here, we investigate the role of the mammalian SWI/SNF (mSWI/SNF) chromatin remodeling complex in NEPC. Using large patient datasets, patient-derived organoids and cancer cell lines, we identify mSWI/SNF subunits that are deregulated in NEPC and demonstrate that SMARCA4 (BRG1) overexpression is associated with aggressive disease. We also show that SWI/SNF complexes interact with different lineage-specific factors in NEPC compared to prostate adenocarcinoma. These data point to a role for mSWI/SNF complexes in therapy-related lineage plasticity, which may also be relevant for other solid tumors.
Asunto(s)
Linaje de la Célula , Plasticidad de la Célula , Proteínas Cromosómicas no Histona/metabolismo , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Factores de Transcripción/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/patología , Línea Celular Tumoral , Estudios de Cohortes , ADN Helicasas/genética , ADN Helicasas/metabolismo , Regulación Neoplásica de la Expresión Génica , Humanos , Estimación de Kaplan-Meier , Masculino , Modelos Biológicos , Invasividad Neoplásica , Proteínas de Neoplasias/metabolismo , Tumores Neuroendocrinos/metabolismo , Tumores Neuroendocrinos/patología , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Neoplasias de la Próstata/genética , Subunidades de Proteína/metabolismo , Factores de Transcripción/genética , Transcriptoma/genéticaRESUMEN
Prostate cancer is the most common malignancy, accounting for about 25% of all incident cases among men in industrialized countries. The human androgen-dependent prostate cancer cell line LNCaP, which is derived from a metastatic lesion of human prostatic adenocarcinoma, is frequently used to study prostate cancer associated signaling pathways in vitro. Recently it was described that Rho GTPase activation in these cells leads to apoptotic responses. We used the bacterial toxins CNFy and CNF1, which specifically and directly activate Rho GTPases by deamidation of a single glutamine. We asked whether these Rho activators could induce apoptosis in LNCaP cells. Our results indicate that RhoA activation, induced by CNFy, does lead to intrinsic apoptosis of the cells. Analysis of the underlying signaling pathway reveals that apoptosis induction requires the activity of Rho kinase (ROCK) and myosin activation, an apoptotic pathway previously identified in cancer stem cells.