Fig. 4

Direct binding of HIF-2α to the LncRNA LINC02609 promoter. (A) The heat-map of cluster analysis of lncRNA based on sequencing results of VHL^(−/−) cells 786-O with HIF2α knockdown. 184 lncRNA transcripts were down-regulated in HIF2α knockdown cell lines. Match to the TANRIC, 47 lncRNA transcripts were found in the database, among which 14 lncRNA transcripts existed higher expression in cancer than in normal. (B) Quantitative real-time PCR detected the 14 lncRNA transcripts in renal cancer cell 786-O and A498 (sh- HIF2α vs. sh-Lacz). (C) The expression of LINC02609 in ccRCC (n = 448) and adjacent normal kidney (n = 67). The data were downloaded from the TCGA-KIRC dataset from TANRIC. (D) Relative expression of LINC02609 in 55 pairs of ccRCC tumor tissues and their corresponding adjacent non-cancerous tissues. The data were downloaded from the TCGA-KIRC. (E) Kaplan-Meier curve showing overall survival of kidney cancer patients with high or low LINC02609 expression (p < 0.0001 by log-rank test). (F) ChIP-real-time PCR were conducted using chromatins isolated from 786-O cells. A specific HIF2α antibody was used, and normal IgG was used as a control. 2% of the total cell lysates was subjected to PCR before immunoprecipitation (input control). The experiments were performed three times independently. (G) APOL1 promoter reporters (pGL4.10-924 wide-type and 924 mutant) and pGL4.73 were co-transfected into 239T cells for 24 h. The APOL1 promoter activity was then examined using a dual luciferase assay kit