Figure 2.

CCK-8 assay showed that let-7b and let-7c enhanced chemosensitivity of 786-O cells to 5-FU. (A) Relative cell survival of 786-O cells at certain time points (24, 48, 60, and 72 h) after transfected with let-7b or let-7c mimics and treated with 5-FU at progressive concentrations (1, 10, 10², 10³, and 10⁴ μmol/l). (B) Relative cell survival of different groups with previous treatment for 24, 48, 60, and 72 h, in which 5-FU is at concentrations of 10 and 10² μmol/l. Cell viability assay showed the inhibition of 786-O cells proliferation by transfection of let-7b and let-7c (*P < 0.05).