CDKN1A and breast cancer: In breast cancer, PMEPA1 reduces PTEN and promotes non‐canonical PI3K/Akt signalling to promote cancer progression.33 In prostate cancer, PMEPA1 inhibits Smad3/4–cmyc–p21Cip1 signalling pathway to promote prostate cancer cell proliferation.10 In lung cancer, PMEPA1 regulates ROS and IRS‐1 signalling and induces EMT to promote metastasis.35 Together, PMEPA1 could be considered as a versatile molecule, which functions the complex roles in different types of cancer.