HK2 and colorectal carcinoma: MEG3 activated by vitamin D can inhibit aerobic glycolysis and lactic acid production in CRC cells by inducing ubiquitin-dependent c-Myc degradation, thereby inhibiting c-Myc target genes expression involved in the glycolysis pathway, such as lactate dehydrogenase A (LDHA), pyruvate kinase muscle 2 (PKM2) and hexokinase 2 (HK2) [72].