Fig. 1: The level of phosho-CHK2 at T68 is upregulated in OR CRCs.

a Viability of CRC oxaliplatin-resistant (OR) cell lines and their parental oxaliplatin-sensitive (P) counterparts after treatment with varying concentrations of oxaliplatin for 3 d. Data are mean ± SEM. The P values were determined by unpaired two-tailed Student’s t test, **P < 0.01, ***P < 0.001. n = 3. b The relative expression level of phosphorylated protein kinases as indicated. Data are mean ± SEM. The P values were determined by unpaired two-tailed Student’s t test, *P < 0.05. n = 3. c Representative western blots of a panel of CRC cell lines (left) and quantification analysis (right). Data are presented as the mean ± SEM. The P values were determined by unpaired two-tailed Student’s t test, *P < 0.05. n = 3. β-Actin served as a loading control. d Representative images of IHC analysis of phosphorylation of CHK2 at Thr68 (pCHK2T68) in sixteen pairs of pretreatment and post-relapse CRC samples from patients treated with the oxaliplatin-based regiment. Magnified images of the boxed areas are shown (left). Scale bar: 100 µm. The H-score of pCHK2T68 in sixteen pairs of pretreatment and postrelapse CRC samples from patients treated with an oxaliplatin-based regiment (right).