Wang et al. (2021) discovered that the immune checkpoint CD276 was highly expressed in cancer stem cells (CSCs), enabling CSCs to evade immune surveillance. TNFRSF4 (CD134/OX40), one of the representative targets of the second-generation immune checkpoints, is considered a promising therapeutic target for antitumor therapy (Bell et al., 2016; Suzuki et al., 2020). Here, TNFRSF4 is linked to cancer.