PCDH9 and hepatocellular carcinoma: Among some recent studies, several lncRNAs have been detected stably in the body fluids of patients, such as lncRNA SNHG1 and RMRP in plasma and lnc-PCDH9–13:1 in saliva, which can be biomarkers for lung cancer patients15 and early hepatocellular carcinoma (HCC)16, respectively.