Antitumor Activities of Immune Costimulatory Molecules of TNF Superfamily in Colorectal and Lung Cancers

Cancer immunotherapy has emerged as a promising treatment that utilizes the innate or adaptive immunity to generate a robust killing of malignant cells. However, only a limited number of cancer patients showed responsiveness to immunotherapies such as checkpoint inhibitors, suggesting the need for potent alternative strategies. In the present study, we explored the therapeutic potentials of costimulatory molecules including TNF superfamily member 4 (TNFSF4), member 9 (TNFSF9), and member 18 (TNFSF18). In tumor samples from human colorectal and lung cancer patients, expression of these factors positively correlated with lymphocyte infiltration and expression of several immune effector genes. In syngeneic mouse tumor models, overexpression of the TNF superfamily costimulatory factors in murine colorectal or lung cancer cells significantly suppressed tumor progression. Especially, TNFSF9 and 18 showed stronger antitumor effects than TNFSF4. Together, our study demonstrated the great potential of cancer immunotherapy targeting these immune costimulatory molecules.