CD274 and neoplasm: The authors claimed that a potential upregulation of PD-L1 in vivo by RSV would render tumor cells more sensitive to immune checkpoints targeting PD-L1 [91], a counterintuitive hypothesis in terms of the potential chemopreventive value of RSV when considering that a putative upregulation of PD-L1 by RSV could enable pre-cancerous lesions to avoid antitumor immunity.