Oral squamous cell carcinoma (OSCC) is a multifactorial malignancy, and its high incidence and mortality rate remain a global public health burden. Polymorphisms in the long intergenic noncoding RNA 673 (LINC00673) have been currently connected to the predisposition to various cancer types. The present study attempted to explore the impact of LINC00673 gene polymorphisms on the risk and progression of OSCC. Three LINC00673 single-nucleotide polymorphisms (SNPs), including rs11655237, rs9914618, and rs6501551, were evaluated in 1231 OSCCC cases and 1194 cancer-free controls. We did not observe any significant association of three individual SNPs with the risk of OSCC between the case and control group. However, while assessing the clinicopathological parameters, patients carrying at least one minor allele of rs9914618 (GA and AA; OR, 1.286; 95% CI, 1.008-1.642; p = 0.043) were found to develop lymph node metastasis more often compared to those who are homozygous for the major allele. Further stratification analyses revealed that this genetic correlation with increased risk of lymphatic spread was further fortified in habitual betel quid chewers (OR, 1.534; 95% CI, 1.160-2.028; p = 0.003) or smokers (OR, 1.320; 95% CI, 1.013-1.721; p = 0.040). Moreover, through analyzing the dataset from The Cancer Genome Atlas (TCGA), we found that elevated LINC00673 levels were associated with the development of large tumors in patients with head and neck squamous cell carcinoma and the risk of lymphatic spread in smokers. These data demonstrate a joint effect of LINC00673 rs9914618 with betel nut chewing or smoking on the progression of oral cancer.
Keywords: long noncoding RNA; lymph node metastasis; oral squamous cell carcinoma; single-nucleotide polymorphism.