TTN-AS1 and hepatocellular carcinoma: In recent years, an lncRNA called TTN antisense RNA 1 (TTN-AS1) was reported to be overexpressed and play oncogenic roles in cervical cancer [24], papillary thyroid cancer [25], gastric cancer [26], hepatocellular carcinoma [27], esophageal squamous cell carcinoma [28], and lung adenocarcinoma [29, 30].