Detection of SF3B3 gene mutations in oral cancer by high resolution melting analysis

There is a high prevalence of oral cancer in Taiwan, which is associated with betel quid chewing. Gene encoding splicing factors, especially splicing factor 3b subunit 1 (SF3B1), have been shown to be the most highly mutated in various hematological malignancies and have a great influence on clinical outcomes. However, few splicing targets have been identified for oral cancer. The aim of this study was to explore splicing factor 3b subunit 3 (SF3B3) gene mutations in oral cancer.

High resolution melting (HRM) analysis was used to characterize SF3B3 polymorphisms. Genomic DNA was extracted from 78 oral cancer tissues, and every exon from exon 2 to exon 26 of the SF3B3 gene was screened by HRM analysis. All results were confirmed by direct DNA sequencing over the range of codons of interest.

Only one single nucleotide polymorphism with amino acid substitution was found to change from serine to asparagine at codon 811 (S811N) in exon 18 with an allele frequency of 1.3%.

The molecular effects of drugs targeting the splicing factors in various cancers may offer a new perspective for the role in cancer progression and the development of novel antitumor therapy. HRM analysis with direct sequencing over the range of codons of interest is a fast, reliable, accurate, and cost-effective screening method to detect unknown gene mutations.