TP53 and cancer: It is well known that CCNA2 is a downstream target of the tumor suppressive signaling p53/p21 pathway and participates in cell cycle transition.35, 36 Overexpression of CCNA2 in PDAC predicts a more infaust histological grade, worse OS, and more advanced tumor stage.37 CCNA2 was shown to act as a oncogene and played a crucial role in regulating cancer cell growth and apoptosis, serving as a new biomarker for the diagnosis and therapy of CRC.38, 39 These findings support the potential of URB1 and CCNA2 as a linkage of crosstalk between mTORC1 and p53/p21 signaling.