The binding of exogenous Hsp70 to PS at high concentrations (10–50 μg/mL) resulted in a concentration-dependent reduction in tumor cell viability (EC50 of Hsp70 = 55 μg/mL) and proliferation, which in turn enhanced the radiosensitization of hypoxic cells [57]. The gene discussed is HSPA1A; the disease is neoplasm.