The role of annexin A4 in cancer.

Annexin A4 (ANXA4) is a member of the annexin family that binds to both calcium ions and phospholipids. Studies indicate that ANXA4 modulates membrane permeability and membrane trafficking, participates in cellular growth and apoptosis, enhances tumor invasion and promotes anti-tumor drug resistance. The overexpression of ANXA4 has been identified in various clinical epithelial tumors including: lung, gastric, colorectal, pancreatic, gallbladder, breast, renal, ovarian, laryngeal, and prostate cancers. In addition, upregulation and nuclear translocation of ANXA4 have been observed in the progression of colorectal cancer and ovarian serous carcinoma. Knockdown of ANXA4 attenuated migration in ovarian cancer and breast cancer cells. In contrast, knockdown of ANXA4 increased susceptibility to platinum in ovarian cancer and malignant mesothelioma cells. It is conceivable that ANXA4 is an indicator for tumor development, invasion, chemo-resistance, poor outcomes of cancer patients, and may be a potential target for therapeutic intervention.