Abstract
Advanced head and neck squamous cell carcinoma (HNSCC) is treated with radiotherapy, chemotherapy, targeted therapy or a combination of these treatments. Variations in toxicity and response to therapy are observed among patients despite similar clinicopathologic characteristics which are attributed to single nucleotide polymorphisms (SNPs). The aim of this review was to evaluate the impact of SNPs on toxicity and response to therapy in HNSCCs. A web-based search of all original articles about the impact of gene polymorphisms on toxicity and response to therapy in HNSCCs was done until September 2021 using international English language databases including Google Scholar, Scopus, PubMed and Web of science. Findings were categorized by type of treatment (radiotherapy, chemotherapy, targeted therapy, or combination therapy). In each category, studies related to growth control genes, cell proliferation, apoptosis, DNA repair genes, antioxidant and drug detoxification genes, genes of drug metabolizing enzymes, tissue remodeling genes and genes of antibody-dependent cellular cytotoxicity were discussed separately. Among studied SNPs with probable impact on toxicity and response to therapy are XRCC1, XRCC3, RAD51, Ku70, NBN, CAT, GSTP1, GSTT1, GSTM1, XPD, XPC, ERCC1, MMP3, ACSL6, EXO1, CXP2D6, FcγRIIIa, AurkA, and EGFR. Understanding gene polymorphisms will help us move toward personalized medicine and determine which patients will actually benefit from therapies for HNSCCs. By examining the SNPs, it is possible to make predictions about the patient's response to treatment or development of toxicity after treatment, and if necessary, make changes in the patient's treatment regimen.