MYC and colorectal carcinoma: Recently, it was shown that exosomes with increased levels of miR-200b-3p—derived from hypoxic cancer-associated fibroblasts from the tumor environment, which inhibit the HMGB3/b-catenin/c-Myc axis—can sensitize CRC cells to the chemotherapy drug 5-fluorouracil (thymidylate synthase inhibitor) [227].