Background MicroRNAs (miRNAs) have been regarded as a critical factor in targeting oncogenes or tumor suppressor genes in tumorigenesis. The genetic predisposition of miRNAs-signaling pathways related to the development of oral squamous cell carcinoma (OSCC) remains unresolved. This study examined the associations of polymorphisms with four miRNAs with the susceptibility and clinicopathological characteristics of OSCC. Methodology/Principal Findings A total of 895 male subjects, including 425 controls and 470 male oral cancer patients, were selected. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and real-time PCR were used to analyze miRNA146a, miRNA196, miRNA499 and miRNA149 genetic polymorphisms between the control group and the case group. This study determined that a significant association of miRNA499 with CC genotype, as compared to the subjects with TT genotype, had a higher risk (AOR = 4.52, 95% CI = 1.24–16.48) of OSCC. Moreover, an impact of those four miRNAs gene polymorphism on the susceptibility of betel nut and tobacco consumption leading to oral cancer was also revealed. We found a protective effect between clinical stage development (AOR = 0.58, 95% CI = 0.36–0.94) and the tumor size growth (AOR = 0.47, 95% CI = 0.28–0.79) in younger patients (age<60). Conclusions Our results suggest that genetic polymorphism of miRNA499 is associated with oral carcinogenesis, and the interaction of the miRNAs genetic polymorphism and environmental carcinogens is also related to an increased risk of oral cancer in Taiwanese.

BackgroundMicro RNAs (miRNAs) are small RNA fragments that naturally exist in the human body. Through various physiological mechanisms, miRNAs can generate different functions for regulating RNA protein levels and balancing abnormalities. Abnormal miRNA expression has been reported to be highly related to several diseases and cancers. Single-nucleotide polymorphisms (SNPs) in miRNAs have been reported to increase patient susceptibility and affect patient prognosis and survival. We adopted a case-control research design to verify the relationship between miRNAs and hepatocellular carcinoma.Methodology/Principal FindingsA total of 525 subjects, including 377 controls and 188 hepatocellular carcinoma patients, were selected. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and real-time PCR were used to analyze miRNA146a (rs2910164), miRNA149 (rs2292832), miRNA196 (rs11614913), and miRNA499 (rs3746444) genetic polymorphisms between the control group and the case group. The results indicate that people who carry the rs3746444 CT or CC genotypes may have a significantly increased susceptibility to hepatocellular carcinoma (adjusted odds ratio [AOR] = 2.84, 95% confidence interval [CI] = 1.88–4.30). In addition, when combined with environmental risk factors, such as smoking and alcohol consumption, interaction effects were observed between gene polymorphisms and environmental factors (odds ratio [OR] = 4.69, 95% CI = 2.52–8.70; AOR = 3.38, 95% CI = 1.68–6.80).ConclusionsThese results suggest that a significant association exists between miRNA499 SNPs and hepatocellular carcinoma. Gene-environment interactions of miRNA499 polymorphisms, smoking, and alcohol consumption might alter hepatocellular carcinoma susceptibility.

SDF-1-3'A gene polymorphism could be considered as a factor related to an increased susceptibility to the risk and pathological development of HCC.

BackgroundIn Taiwan, oral cancer has causally been associated with environmental carcinogens. Carbonic anhydrase 9 (CA9) is reportedly overexpressed in several types of carcinomas and is generally considered a marker of malignancy. The current study explored the combined effect of CA9 gene polymorphisms and exposure to environmental carcinogens on the susceptibility of developing oral squamous cell carcinoma (OSCC) and the clinicopathological characteristics of the tumors.Methodology and Principal FindingsFour single-nucleotide polymorphisms (SNPs) of the CA9 gene from 462 patients with oral cancer and 519 non-cancer controls were analyzed by a real-time polymerase chain reaction (PCR). While the studied SNPs (CA9 rs2071676, rs3829078, rs1048638 and +376 Del) were not associated with susceptibility to oral cancer, the GAA haplotype of 3 CA9 SNPs (rs2071676, rs3829078, and rs1048638) was related to a higher risk of oral cancer. Moreover, the four CA9 SNPs combined with betel quid chewing and/or tobacco consumption could robustly elevate susceptibility to oral cancer. Finally, patients with oral cancer who had at least one G allele of CA9 rs2071676 were at higher risk for developing lymph-node metastasis (p = 0.022), compared to those patients homozygous for AA.ConclusionsOur results suggest that the haplotype of rs2071676, rs3829078, and rs1048638 combined has potential predictive significance in oral carcinogenesis. Gene-environment interactions of CA9 polymorphisms, smoking, and betel-quid chewing might alter oral cancer susceptibility and metastasis.