PIK3C3 reversed the promotive effects of miR-340-5p on esophageal squamous cell carcinoma (ESCC) cell proliferation. (A, B) MTT assay was adopted to analyze the cell viability in control, anti-340-5p and anti-340-5p+PIK3C3 treated KYSE-150 and TE-12 cells, * P<0.05. (C, D) Colony formation assay was utilized to estimate the cell proliferation in control, anti-340-5p, and anti-340-5p+PIK3C3 transfected KYSE-150 and TE-12 cells, * P<0.05. (E) Relative expression of miR-340-5p was estimated by qRT-PCR in ESCC and normal tissue samples, * P<0.05. (F) Correlation between miR-340-5p and PIK3C3 in ESCC samples was assessed.