No abstract

Hepatocellular carcinoma (HCC) is a prevalent primary neoplasm of the liver, whose heterogeneous global incidence suggests the likely impact of genetic variations among individuals on the susceptibility to this disease. Increasing evidence indicates that melatonin exhibits oncostatic properties in many cancer types at least in part mediated by its membrane-bound receptors, melatonin receptor 1A (encoded by MTNR1A) and 1B (MTNR1B). In this study, the effect of melatonin receptor gene polymorphisms on the risk and progression of hepatic tumors was evaluated between 335 HCC patients and 1196 cancer-free subjects. We detected a significant association of MTNR1A single nucleotide polymorphism (SNP), rs6553010, with the elevated risk of HCC (AOR, 1.587; 95% CI, 1.053–2.389; p = 0.027) after being adjusted for two potential confounders, age and alcohol use. In addition, patients who carry at least one polymorphic allele (heterozygote or homozygote) of MTNR1A rs2119882 or rs2375801 were more prone to develop distant metastasis (OR, 5.202; 95% CI, 1.163–23.270; p = 0.031, and OR, 7.782; 95% CI, 1.015–59.663; p = 0.048, for rs2119882 and rs2375801, respectively). Further analyses revealed that rs2119882 is located on the consensus binding site of GATA2 transcription factor within the promoter region of MTNR1A gene, and that a correlation between the levels of GATA2 and melatonin receptor 1A was observed in the TCGA (The Cancer Genome Atlas) dataset. Moreover, individuals bearing a specific haplotype of four MTNR1B SNPs were more prone to develop HCC. In conclusion, our data suggest an association of melatonin receptor gene polymorphisms with the risk of HCC and hepatic cancer metastasis.

Hepatocellular carcinoma (HCC) is one of the most common malignancies in the world, especially, in eastern Asia, and its prognosis is poor once metastasis occurs. Niclosamide, a US Food and Drug Administration-approved antihelmintic drug, was shown to inhibit the growth of various cancers including HCC, but the effect of niclosamide on cell motility and the underlying mechanism have not yet been completely defined. The present study demonstrated that niclosamide, at 0-40 nM, concentration-dependently inhibited wound closure and the migratory/invasive capacities of human Huh7 and SK-Hep-1 HCC cells without exhibiting cytotoxicity. A protease array analysis showed that CD10 was dramatically downregulated in Huh7 cells after niclosamide treatment. Western blot and flow cytometric assays further demonstrated that CD10 expression was concentration-dependently downregulated in Huh7 and SK-Hep-1 cells after niclosamide treatment. Mechanistic investigations found that niclosamide suppressed Twist-mediated CD10 transactivation. Moreover, knockdown of CD10 expression by CD10 small interfering RNA in HCC cells suppressed cell migratory/invasive abilities and overexpression of CD10 relieved the migration inhibition induced by niclosamide. Taken together, our results indicated that niclosamide could be a potential agent for inhibiting metastasis of HCC, and CD10 is an important target of niclosamide for suppressing the motility of HCC cells.