MMP9 and neoplasm: In oesophageal squamous cell carcinoma (ESCC) and glioblastoma (GBM), SRGN can indirectly upregulate the expression of MMP2/MMP9 by activating the ERK pathway, TGF‐β signalling, or the CXCLs/CXCR2 axis, thereby enhancing tumour invasion and metastasis.57, 58