CD274 and gastric cancer: Several miRNAs have been shown to directly regulate the expression of PD-L1, including miR-142-5p, miR-93, and miR106b in pancreatic cancer [156, 157]; miR-138-5p in colorectal cancer [158]; miR-217 in laryngeal cancer [159]; miR-17-5p in melanoma [160]; miR-200b, miR-152, and miR-570 in gastric cancer [161, 162]; miR-15a, miR-193a, and miR-16 in malignant pleural mesothelioma [163]; miR-497-5p in clear cell renal cell carcinoma [164]; and miR-140, miR-142, miR-340, and miR-383 in cervical cancer [165].