HSPA5 and neoplasm: Moreover, while tumors express many antigens, cs78 can serve as an autoantigen that triggers the production of anti-GRP78 autoantibodies, which upon binding to cs78 induces inositol triphosphate-mediated ER Ca2+ release, leading to promotion of tissue factor (TF) procoagulant activity, which in turn promotes tumor growth and metastasis (74).