Fig. 1

CDKL1 is lowly expressed and inhibits the growth and proliferation of lung cancer cells. (A) The TCGA database was utilized to predict the mRNA levels of CDKL1 in both LUAD (N = 59, T = 483) and LUSC patients (N = 50, T = 486). * P < 0.05. (B) The expression of CDKL1 in various lung cancer cell lines was assessed by western blot analysis. The grey values of the bands were quantitatively analyzed, and the expression level of CDKL1 was normalized to that of GAPDH (* P < 0.05, ** P < 0.01, *** P < 0.001). (C) Western blot analysis was used to assess CDKL1 protein expression in A549 and H1299 cells with CDKL1 overexpression or knockdown. In lung cancer cell lines with CDKL1 overexpression, CDKL1 protein levels were assessed using CDKL1 or Flag antibodies. (D) Cell growth ability was examined by cell growth curves every other day in A549 and H1299 cells with either CDKL1 overexpression or knockdown (** P < 0.01, *** P < 0.001). (E) A549 and H1299 cells with CDKL1 overexpression or knockdown were seeded into 6-well plates at a density of 500 cells per well. After two weeks, the number of clones (> 50 cells) was determined (** P < 0.01, *** P < 0.001). (F) The proliferation ability of the A549 and H1299 cells was evaluated using the EdU assay. The percentage of EdU-positive cells was calculated (** P < 0.01, *** P < 0.001). Scale bar, 100 μm