MYC and breast cancer: As MYC family members are frequently amplified or overexpressed in cancer, the regulation of polyamine biosynthesis by MYC family genes emerges as a significant contributory factor in various cancer types, such as myeloproliferative neoplasms (MPNs) [221, 222], neuroblastoma [93, 223], CRC [224] and breast cancers [225, 226].