USP2 and malignant colon neoplasm: An dose of 10 or 20 mg kg−1 salvianolic acid B in mice transplanted with MC38 colon cancer cells showed a tumour suppression rate of 43.4% and 63.2%, respectively, by inhibiting the ubiquitin carboxy‐terminal hydrolase 2 (USP2) and, ultimately, downregulation of programmed death‐ligand 1 (PD‐L1), thus enhancing the killing activity of T cells (Kuang et al. 2023).