Project description:Introduction: Neuroendocrine prostate cancer (NEPC) is an aggressive subtype of prostate cancer, exhibiting rapid progression and is unresponsive to hormone therapy. Reliable prognostic assays and more effective treatments are critically required. However, the research of NEPC has been hampered by a lack of clinically relevant in vivo models. Recently, we successfully developed a first-in-field patient tissue-derived xenograft model of complete neuroendocrine transdifferentiation from prostate adenocarcinoma. By comparing gene expression profiles of the parental adenocarcinoma line (LTL331) and the NEPC subline (LTL331R), we identified DEK, a gene not previously reported in prostate cancer, as a potential biomarker and target for NEPC. Methods: DEK protein expression in patient tissue-derived xenograft models and clinical samples was assessed by immunohistochemistry. The function of DEK was determined by siRNA-induced reduction of DEK expression in PC-3 cells, a cell line with NEPC characteristics, followed by functional assays and gene expression profiling analysis. Results: Elevated DEK protein expression was observed in all clinical NEPC cases, which is distinct from their benign counterparts (0%), hormonal naïve prostate cancer (2.45%) and castration resistant prostate cancer (29.55%). Increased DEK expression is an independent clinical risk factor and is associated with shorter disease free survival in hormonal naïve prostate cancer patients. Reduction of DEK expression in PC-3 cells led to a marked reduction in cell proliferation, cell migration and invasion. Conclusions: The results suggest that DEK may play an important role in the progression of prostate cancer, especially NEPC and provide a potential biomarker to aid risk stratification of prostate cancer and a novel therapeutic target for treating NEPC. The function of DEK was determined by siRNA-induced reduction of DEK expression in PC-3 cells, a cell line with NEPC characteristics, followed by functional assays and gene expression profiling analysis.
Project description:Introduction: Neuroendocrine prostate cancer (NEPC) is an aggressive subtype of prostate cancer, exhibiting rapid progression and is unresponsive to hormone therapy. Reliable prognostic assays and more effective treatments are critically required. However, the research of NEPC has been hampered by a lack of clinically relevant in vivo models. Recently, we successfully developed a first-in-field patient tissue-derived xenograft model of complete neuroendocrine transdifferentiation from prostate adenocarcinoma. By comparing gene expression profiles of the parental adenocarcinoma line (LTL331) and the NEPC subline (LTL331R), we identified DEK, a gene not previously reported in prostate cancer, as a potential biomarker and target for NEPC. Methods: DEK protein expression in patient tissue-derived xenograft models and clinical samples was assessed by immunohistochemistry. The function of DEK was determined by siRNA-induced reduction of DEK expression in PC-3 cells, a cell line with NEPC characteristics, followed by functional assays and gene expression profiling analysis. Results: Elevated DEK protein expression was observed in all clinical NEPC cases, which is distinct from their benign counterparts (0%), hormonal naïve prostate cancer (2.45%) and castration resistant prostate cancer (29.55%). Increased DEK expression is an independent clinical risk factor and is associated with shorter disease free survival in hormonal naïve prostate cancer patients. Reduction of DEK expression in PC-3 cells led to a marked reduction in cell proliferation, cell migration and invasion. Conclusions: The results suggest that DEK may play an important role in the progression of prostate cancer, especially NEPC and provide a potential biomarker to aid risk stratification of prostate cancer and a novel therapeutic target for treating NEPC.
Project description:<p>BRCA1 mutations are a hallmark of hereditary ovarian cancer, strongly linked to deficiencies in homologous recombination (HR) DNA repair and impaired DNA replication fork protection. However, its roles in cancer progression beyond maintaining genomic integrity remain poorly understood. Through metabolomics approaches, we found BRCA1-deficiency strikingly increased choline metabolism. Loss of BRCA1 promotes choline uptake through upregulating choline transporter-like protein 4 (CTL4). BRCA1 directly binds and recruits EZH2-mediated H3K27Me3 deposition to CTL4 promoter. CTL4 was therefore overexpressed in ovarian cancer tissues with BRCA1 mutations. Furthermore, BRCA1-deficiency significantly promotes ovarian cancer invasion, while inhibition of CTL4 reverses the high metastatic potential of BRCA1-deficient ovarian cancer cells, suggesting the functionality and specificity of CTL4 as a therapeutic target. Additionally, we discovered that phosphocholine, the choline metabolite increased by CTL4 overexpression, interacted with and stabilized the epithelial-to-mesenchymal transition inducer FAM3C in BRCA1-deficient ovarian cancer cells. Importantly, we identified a potent CTL4 inhibitor, DT-13, which significantly reduces choline metabolism and effectively suppresses metastasis in BRCA1-deficient ovarian cancers. Therefore, our study uncovers a mechanism underlying metastasis in BRCA1-deficient cancers and identifies CTL4 as a therapeutic target for metastatic ovarian cancer patients with BRCA1 mutations.</p>
Project description:Potent therapeutic inhibition of the androgen receptor (AR) in prostate adenocarcinoma can lead to the emergence of neuroendocrine prostate cancer (NEPC), a phenomenon associated with enhanced cell plasticity. Here, we show that microRNA-194 (miR-194) is a regulator of epithelial-neuroendocrine transdifferentiation. In clinical prostate cancer samples, miR-194 expression and activity were elevated in NEPC and inversely correlated with AR signalling. Over-expression of miR-194 facilitated the emergence of neuroendocrine features in prostate cancer cells, a process mediated by its ability to directly target a suite of genes involved in cell plasticity. One such target gene was FOXA1, which encodes a transcription factor with a vital role in maintaining the prostate epithelial lineage. Importantly, a miR-194 inhibitor blocked epithelial-neuroendocrine transdifferentiation and inhibited the growth of cell lines and patient-derived organoids possessing neuroendocrine features. Overall, our study reveals a post-transcriptional mechanism regulating the plasticity of prostate cancer cells and provides a rationale for targeting miR-194 in NEPC.
Project description:Potent therapeutic inhibition of the androgen receptor (AR) in prostate adenocarcinoma can lead to the emergence of neuroendocrine prostate cancer (NEPC), a phenomenon associated with enhanced cell plasticity. Here, we show that microRNA-194 (miR-194) is a regulator of epithelial-neuroendocrine transdifferentiation. In clinical prostate cancer samples, miR-194 expression and activity were elevated in NEPC and inversely correlated with AR signalling. Over-expression of miR-194 facilitated the emergence of neuroendocrine features in prostate cancer cells, a process mediated by its ability to directly target a suite of genes involved in cell plasticity. One such target gene was FOXA1, which encodes a transcription factor with a vital role in maintaining the prostate epithelial lineage. Importantly, a miR-194 inhibitor blocked epithelial-neuroendocrine transdifferentiation and inhibited the growth of cell lines and patient-derived organoids possessing neuroendocrine features. Overall, our study reveals a post-transcriptional mechanism regulating the plasticity of prostate cancer cells and provides a rationale for targeting miR-194 in NEPC.
Project description:Potent therapeutic inhibition of the androgen receptor (AR) in prostate adenocarcinoma can lead to the emergence of neuroendocrine prostate cancer (NEPC), a phenomenon associated with enhanced cell plasticity. Here, we show that microRNA-194 (miR-194) is a regulator of epithelial-neuroendocrine transdifferentiation. In clinical prostate cancer samples, miR-194 expression and activity were elevated in NEPC and inversely correlated with AR signalling. Over-expression of miR-194 facilitated the emergence of neuroendocrine features in prostate cancer cells, a process mediated by its ability to directly target a suite of genes involved in cell plasticity. One such target gene was FOXA1, which encodes a transcription factor with a vital role in maintaining the prostate epithelial lineage. Importantly, a miR-194 inhibitor blocked epithelial-neuroendocrine transdifferentiation and inhibited the growth of cell lines and patient-derived organoids possessing neuroendocrine features. Overall, our study reveals a post-transcriptional mechanism regulating the plasticity of prostate cancer cells and provides a rationale for targeting miR-194 in NEPC.
Project description:The high heterogeneity and low percentage of neuroendocrine cells in prostate cancer limit the utility of traditional bulk RNA sequencing and even single-cell RNA sequencing to find better biomarkers for early diagnosis and stratification. Re-clustering of specific cell-type holds great promise for identification of intra-cell-type heterogeneity. However, this has not yet been used in studying neuroendocrine prostate cancer heterogeneity. Neuroendocrine cluster(s) were individually identified in each castration-resistant prostate cancer specimen and combined for trajectory analysis. Three neuroendocrine states were identified. Neuroendocrine state 2 with the highest AR score was considered the initial starting state of neuroendocrine transdifferentiation. State 1 and state 3 with distinct high neuroendocrine scores and marker genes enriched in N-Myc and REST target genes, respectively, were considered as two different types of neuroendocrine differentiated cancer cells. These two states contained distinct groups of prostate cancer biomarkers and a strong distinguishing ability of normal versus cancerous prostate across different pathological grading was found in the N-Myc-associated state. Our data highlight the central role of N-Myc and REST in mediating lineage plasticity and classifying neuroendocrine phenotypes.