PVT1 and lung cancer: Recent clinical studies have demonstrated that increased PVT1 expression is correlated with poor survival in different types of cancers, including gastric cancer [24–29], colorectal cancer [30], lung cancer [20, 21, 31, 32], hepatocellular carcinoma [22, 33], bladder cancer [34], pancreatic cancer [35], cervical cancer [36, 37], ovarian cancer [38], esophageal cancer [39] and osteosarcoma [40].