MMP1 and oral cavity squamous cell carcinoma: ACOX1 can be combined with MMP1, suppressor of cytokine signaling 3 (SOCS3) to diagnose oral squamous cell carcinoma (OSCC), and downregulation in bladder cancer might be due to PDK1 down-regulation, suggesting that it might serve as a potential biomarker and therapeutic target for bladder [37,38].