Figure 3. RNAi-induced silencing of endogenous ALKBH5 promoted in vitro proliferation and in vivo tumorigenesis of ESCC cells. (A, B) qRT-PCR (A) and western blot (B) analysis of ALKBH5 expression in shSCR-expressing (LV-shSCR) and shALKBH5-expressing (LV-shALKBH5-1 and LV-shALKBH5-2) ESCC cells (TE-13 and Eca-109 cells). (C, D) A colony formation assay was performed to study the proliferation ability of shSCR- and shALKBH5-expressing ESCC cells. Left panels show representative images of colony formation assay (C) and right panels signify the total colony count (D). (E, F) Effects of RNAi-induced ALKBH5 silencing on cell cycle distribution in TE-13 and Eca-109 cells. (G–I) ALKBH5 knockdown enhanced tumor growth of TE-13 cells in nude mice. shSCR- or shALKBH5-expressing TE-13 cells were subcutaneously injected into the left and right dorsal thighs of mice, respectively. (G) Representative image of tumors formed. (H) Growth curve of tumor volumes. (I) Tumors were weighed.