KLF2 increased the sensitivity of tumor-bearing mice to cisplatin by inhibiting WEE1 in vivo. Mice were injected with cisplatin-treated MDA-MB-231 cells that had been transfected with oe-KLF2 or in combination with oe-WEE1. A, The mRNA expression of KLF2 and WEE1 detected in tumor tissues of nude mice by RT-qPCR. B, The protein expression of KLF2 and WEE1 in tumor tissues of nude mice by Western blot. C, Tumor weight in nude mice. D, H&E staining of lung tissues of nude mice. E, The protein expression of MMP-2, MMP-9, Bax, and Bcl-2 in tumor tissues of nude mice detected by Western blot. * p < .05, indicates the comparison between two groups. n = 6