Fig. 6: PRR14 inhibits CHEK2.

CHEK2 mRNA expression (a), CHEK2 protein expression (b) and p-CHEK2 (T68) protein expression (c) in PRR14 genetically unaltered and altered (amplified and mutated) breast cancer cases in TCGA database are statistically analyzed by two-tailed Student’s t-test. CHEK2 protein expression is detected by immunostaining in xenografts in nude mice from established MCF7 cell lines and MDA-MB-231 cell lines (d), as well as human breast cancer (e). CHEK2 transcription in human breast cancer is also detected by qRT-PCR (f). The data are quantified and two-tailed Student’s t-test is employed to determine the significance of the difference. Established MCF7 and MDA-MB-231 (g) PRR14-overexpressing and control cell lines are treated with various of genotoxic chemicals including Bleo, Eto, 5-FU, H2O2 and HU at indicated concentrations for indicated time. Key components of the ATM/CHEK2/P53 signaling pathway are detected by immunostaining. And CHEK2 protein expression (h) and mRNA expression (i) are detected by immunostaining and qRT-PCR, respectively. The data are analyzed by two-tailed Student’s t-test. Established MCF7 and MDA-MB-231 (j) PRR14-overexpressing and control cell lines are treated with Eto at indicated concentration for indicated time to induce p-CHEK2 (T68), which is detected by immunostaining and quantified and normalized by CHEK2 total protein (k). The data are analyzed by two-tailed Student’s t-test.