Journal: International Journal of Biological Sciences
Article Title: The castration-resistant prostate cancer-associated SNP rs11067228 facilitates neuroendocrine differentiation through an enhancer-mediated chromatin interaction with SRRM4
doi: 10.7150/ijbs.124731
Figure Lengend Snippet: SNP rs11067228 is a functional SNP in 22Rv1 cells. (A) Transwell assays in 22Rv1 cells homozygous for the non-risk (G/G, WT) versus risk (A/A, MUT) alleles of rs11067228. Scale bar =100 μm. Cells that had migrated to lower chambers were stained with 0.1% crystal violet. Quantification is at right. Data represent means ± SEM of three independent experiments. **P < 0.01. (B) Soft agar colony formation analysis of WT (G/G) versus MUT (A/A) 22Rv1 cells. Scale bar =100 μm. Quantification is at right. Data represent means ± SEM of three independent experiments. **P < 0.01. (C, D) LDH assays comparing WT (G/G) and MUT (A/A) cells treated with enzalutamide. LDH release was assayed at 24 (C) and 48 (D) hours after treatment. Data represent means ± S.E.M. of three independent experiments. ***P < 0.001, **P < 0.01. (E) MTS assays comparing WT (G/G) and MUT (A/A) cells treated with enzalutamide. Data represent means ± S.E.M. of three independent experiments. **P < 0.01. (F) Real-time qPCR validation of transcript levels of indicated NE-related genes in WT (G/G) versus MUT (A/A) cells. Data represent means ± SEM of three independent experiments. ***P < 0.001, **P < 0.01. (G) Heatmap of differentially-expressed genes in two samples of 22Rv1 cells harboring the non-risk (G) allele (WT) and two groups of MUT cells harboring the risk (A) allele, based on RNA-seq (|log2fold change| >1 and p-adjusted value <0.05). (H) KEGG pathway showing biological processes of genes upregulated in MUT relative to WT cells (Top 10). (I) Overlap of genes down-regulated in enhancer KO versus WT lines (p-adjusted value <0.05) (green), with the number of genes up-regulated in lines harboring MUT (A/A) versus WT (G/G) cells (log2fold-change >1; p-adjusted value <0.05) (blue). (J, K) Real-time qPCR and western blot analysis validation of transcript levels of indicated target genes of the risk enhancer in MUT and WT cells. Data represents means ± S.E.M. of three independent experiments. ***P < 0.001, **P < 0.01. (L) Real-time qPCR validation of transcript levels of EMT-related genes in WT (G/G), enhancer KO, and MUT (A/A) cells. Data represent means ± SEM of three independent experiments. ***P < 0.001, **P < 0.01, *P < 0.05. (M-O) Photograph showing 22Rv1 xenografts in nude mice with WT (G/G), enhancer KO, enhancer KO cells subjected to CRISPRa to re-express SRRM4 and MUT (A/A). Tumor volume was measured once a week at indicated time points. Tumor weight was measured when sacrificed (n = 6 per group). Data represent means ± SEM of three independent experiments. ***P < 0.001, **P < 0.01, n.s., not significant. (P) Representative immunohistochemistry staining of indicated 22Rv1 xenografts in (M). Scale bar =100 μm.
Article Snippet: The human PCa cell lines 22Rv1, LNCaP and C4-2B were obtained from the American Type Culture Collection (ATCC).
Techniques: Functional Assay, Staining, Biomarker Discovery, RNA Sequencing, Western Blot, Immunohistochemistry