For instance, MMP1, 3, 9 and 10-14 were highly expressed in breast cancer, colon adenocarcinoma, esophageal cancer, head and neck cancer, etc. However, some MMPs are downregulated in some cancers, such as MMP2 and 23B in breast cancer, bladder cancer, lung squamous cancer and uterine corpus endometrial carcinoma 17. The gene discussed is MMP2; the disease is breast cancer.