Fig. 5

CCDC109B expression is induced by hypoxia and regulated by HIF1α. a Representative IHC images of CCDC109B and HIF1α in primary human GBM tissues. Magnification ×100 and ×200. b Analysis of HIF1α and CCDC109B expression in human GBM tissues by IHC staining. Magnification ×200 and ×400. Representative images were labeled as case 1 and case 2. c Western blot analysis of HIF1α in U87MG, T98, U251 and NHA. d qRT-PCR were used to determine mRNA levels of CCDC109B in U87MG or U251 cells cultured under normoxic or hypoxic conditions. e Western blot analysis for HIF1α and CCDC109B protein levels in U87MG and U251 cells cultured under hypoxia for the indicated time. f Western blot analysis for HIF1α and CCDC109B in U87MG and U251 cells transfected with NC, si-HIF1α-1 or si-HIF1α-2 under normoxic or hypoxic conditions for 48 h. g Western blot analysis for HIF1α and CCDC109B in U87MG and U251 cells treated with PX478 (0, 50, 75, 100 μM) and cultured under normoxic or hypoxic conditions for 48 h. h Representative images of implanted nude mice injected intraperitoneally with saline or digoxin (2 mg/kg) every day for one month. Images for corresponding subcutaneous U87MG xenografts after surgical removal are also shown. i Western blot analysis to determine levels of HIF1α and CCDC109B in tumors from nude mice treated with saline or digoxin. Data are presented as the mean ± SEM (***P < 0.001)