CDKN1A and lung cancer: Commonly, LRF/ZBTB7A has been shown to promote progression through the S phase of the cell cycle in colorectal, osteosarcoma, and cervical cancer cells by transcriptionally repressing p21 [59, 68], whereas its depletion induces G1 cell cycle arrest through increased expression of p53 and p21 in chondrosarcoma and lung cancer cells [57, 59, 69].