CSF2 and cancer: It prolonged the survival of patients in a few clinical trials.153 A STING agonist formulated with GM-CSF showed remarkable antitumor efficacy in multiple established tumors.154 Some tumor cells used as whole-cell vaccines can secrete GM-CSF.155,156 In addition, oncolytic virotherapy, which increases the targeting of cancer cells through virus infection, could induce antitumor immune responses, especially in cells that had been engineered to express GM-CSF.157,158 GM-CSF is combined for the purpose of enhancing DC functions and limiting Treg regulation.