Hepatocellular Carcinoma Up-regulated Long Non-coding RNA (HULC) and Clock circadian regulator (CLOCK) mRNA 5′-UTR have a complementary base paring region, and the results of luciferase reporter gene assays suggest that HULC can improve the stability of CLOCK mRNA (Fig. 4b). The gene discussed is HULC; the disease is hepatocellular carcinoma.