USP7 and neoplasm: Studies have found that USP7 inhibitors P5091 and Parthenolide inhibits Wnt signaling and colorectal tumor growth; specific inhibitor HBX 19818 can selectively reduce the activity of USP7; USP7 small-molecule inhibitors P5091 and P22077 can induce tumor cell apoptosis by enhancing intracellular oxidative stress response and endoplasmic reticulum stress response [40,188,189,190,191].