In PDAC and CRC, a study found that resistance to anti-KRAS therapy may be driven by deubiquitinase USP21, which promotes KRAS-independent tumor growth by regulating MARK3-induced macrophagocytosis, and thus, USP21 may serve as a new target for the treatment of pancreatic cancer [105]. The gene discussed is KRAS; the disease is colorectal carcinoma.