Genetic Polymorphisms in Genes Involved in Oxidative Stress and Their Association with Radiotherapy Toxicity among...

Area of Science:

• Oncology
• Genetics
• Radiotherapy

Background:

• Radiotherapy for head and neck cancer (HNC) can cause adverse normal tissue effects.
• Genetic variations in antioxidant enzymes like superoxide dismutase (SOD) and catalase (CAT) may influence individual susceptibility to these toxicities.

Purpose of the Study:

• To investigate the association between polymorphisms in SOD and CAT genes and the risk of acute radiation-induced toxicity in HNC patients.
• To determine if specific gene variants correlate with adverse effects such as skin toxicity and oral mucositis.

Main Methods:

• Genotyping of single nucleotide polymorphisms (SNPs) in SOD1, SOD2, SOD3, and CAT genes using PCR-RFLP in 250 HNC patients.
• Systematic documentation of acute radiation-induced toxicity and treatment response during radiotherapy.

Main Results:

• The SOD3 G172A variant and combined variant genotypes showed a protective effect against acute radiation-induced skin toxicity.
• The SOD3 172A/A genotype was strongly associated with an increased risk of oral mucositis (OR = 10.47).
• The CAT A21T heterozygous genotype was linked to a higher risk of oral mucositis (OR = 1.79).

Conclusions:

• Genetic polymorphisms in SOD3 are significantly associated with radiation-induced skin toxicity and mucositis in HNC patients.
• These findings highlight the potential role of SOD3 variants in predicting patient response to radiotherapy and managing side effects.