ABSTRACT
Chromodomain-helicase-DNA-binding protein 1 (CHD1) deletion is among the most common mutations in prostate cancer (PCa), but its role remains unclear. In this study, RNA sequencing was conducted in PCa cells after clustered regularly interspaced palindromic repeat (CRISPR)/CRISPR-associated protein 9 (Cas9)-based CHD1 knockout. Gene set enrichment analysis (GSEA) indicated upregulation of hypoxia-related pathways. A subsequent study confirmed that CHD1 deletion significantly upregulated hypoxia-inducible factor 1α (HIF1α) expression. Mechanistic investigation revealed that CHD1 deletion upregulated HIF1α by transcriptionally downregulating prolyl hydroxylase domain protein 2 (PHD2), a prolyl hydroxylase catalyzing the hydroxylation of HIF1α and thus promoting its degradation by the E3 ligase von Hippel-Lindau tumor suppressor (VHL). Functional analysis showed that CHD1 deletion promoted angiogenesis and glycolysis, possibly through HIF1α target genes. Taken together, these findings indicate that CHD1 deletion enhances HIF1α expression through PHD2 downregulation and therefore promotes angiogenesis and metabolic reprogramming in PCa.
Subject(s)
Male , Humans , Von Hippel-Lindau Tumor Suppressor Protein/metabolism , DNA-Binding Proteins/metabolism , Prolyl Hydroxylases/metabolism , Hypoxia , Prostatic Neoplasms/pathology , Glycolysis , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Cell Line, Tumor , DNA Helicases/metabolismABSTRACT
<p><b>OBJECTIVE</b>To investigate the role and significance of epithelial-mesenchymal transition (EMT) and its transcriptional regulator Twist1 in the development of the human fetal prostate.</p><p><b>METHODS</b>Twenty-five human fetal prostate specimens at various developmental stages (16-39 weeks) were included in this study. EMT markers, such as E-Cadherin, N-Cadherin and Vimentin, and EMT transcriptional regulator Twist1 were determined by immunohistochemistry, and their relationship with the development of the human fetal prostate was analyzed.</p><p><b>RESULTS</b>E-Cadherin was expressed in the fetal prostate epithelium only, while Vimentin, N-Cadherin and Twist1 in both the epithelium and the stroma. The expression of E-Cadherin gradually increased, but those of Vimentin, N-Cadherin and Twist1 gradually decreased with the gestation stages. No significant changes were observed in the staining patterns of Vimentin, N-Cadherin and Twist1 in the stroma during the whole developmental process.</p><p><b>CONCLUSION</b>EMT is involved in the development of the human fetal prostate, which may promote epithelial cell motility to form prostatic bud tubules in early gestation stages and boost the differentiation of prostate epithelia in later stages.</p>
Subject(s)
Humans , Male , Cadherins , Metabolism , Cell Dedifferentiation , Epithelial Cells , Metabolism , Epithelial-Mesenchymal Transition , Fetal Development , Mesoderm , Metabolism , Nuclear Proteins , Metabolism , Prostate , Embryology , Metabolism , Twist-Related Protein 1 , Metabolism , Vimentin , MetabolismABSTRACT
<p><b>OBJECTIVE</b>To screen and compare the specific transcription factors that repress the epithelial phenotype in epithelial-mesenchymal transition (EMT) in two different human prostate cancer models LNCaP/HIF1alpha and ARCaP.</p><p><b>METHODS</b>We established two different prostate cancer EMT models, LNCaP/HIF1alpha and ARCaP, cultured LNCaP, LNCaP/HIF1alpha, IF11 and IA8 cells in vitro, and detected the five transcription factors Snail, Slug, ZEB1, SIP1 and Twist1 in these cells by RT-PCR.</p><p><b>RESULTS</b>Different levels of Snail, Slug, ZEB1, SIP1 and Twist1 were detected in both LNCaP and LNCaP/HIF1alpha cells, with significant differences only in the expressions of Slug and Twist1 between the two cells. The expression of Slug was increased, but that of Twist1 decreased in the LNCaP/HIF1alpha cells. All the five transcription factors but Twist1 were expressed in both the IF11 and IA8 cells, but only the express- sions of ZEB1 and Slug were increased significantly in the IA8 cells.</p><p><b>CONCLUSION</b>There are different mechanisms underlying transcriptional regulation in different prostate cancer EMT models. Slug may be one of the key transcription factors involved in the HIF1alpha-induced EMT of LNCaP cells, while ZEB1 and Slug may play an important role in repressing the epithelial phenotype of the ARCaP model.</p>