Silencing HN1L caused cell cycle arrest by interfering MAPK pathway. (a) Cell cycle distributions were analyzed by flow cytometry. *P < 0.05 (Chi-squared test). (b) Western blot analyzed the protein levels of several cell cycle regulators in sh-HN1L, sh-control and parental cells. β-Tubulin was used as a loading control. (c) Representative IHC images of p21 and p53 expressions in xenograft tumors. Scale bar, 150 μm. (d) Western blot analysis was applied to detect the phosphorylation levels of the key mediators in MAPK pathway (phospho-c-Raf(Ser259), phospho-MEK1/2(Ser217/221), phospho-Erk1/2(Thr202/204), phospho-p90RSK(Ser380) and phospho-Elk-1(Ser383)). β-Tubulin was used as a loading control. (e) The phosphorylation levels of Akt(Thr308/Ser473) was tested by western blotting. β-Actin was used as a loading control.