In lung cancer, knockdown of UBE2M can promote the expression of cyclin-dependent kinase inhibitor 1 (CDKN1A and CDKN1B) and cyclin-associated proteins (such as G2/mitotic-specific cyclin-B1, Cyclin-A2, G1/S-specific cyclin-D3, and Cyclin-dependent kinase 4 homolog) in cell cycle progression. The gene discussed is CDKN1A; the disease is lung cancer.