IL1A & IL1B genetic polymorphisms are risk factors for thyroid cancer in a Chinese Han population

Thyroid carcinoma accounts for a large proportion of endocrine neoplasia, and the relationship between inflammation and thyroid cancer has been previously validated. IL-1α (Interleukin 1 alpha) and IL-1β (Interleukin 1 beta), encoded by IL1A and IL1B, respectively, are implicated in numerous inflammatory responses and in tumor progression. The objective of this research was to assess the association of genetic polymorphisms of IL1A and IL1B with the risk of thyroid cancer in a Chinese Han population.

Genotypes of the 12 candidate SNPs in IL1A and IL1B were identified among 208 thyroid cancer patients and 279 healthy controls using an Agena MassARRY method. Genetic model analysis was carried out to evaluate the significant links between the variants and thyroid cancer risk. HaploReg v4.1 and the GTEx database were used for SNP functional annotation and expression quantitative trait loci (eQTL) analysis, respectively.

Significant associations were detected between IL1A rs3783521 and an increased thyroid cancer risk in our study population (p < 0.05). IL1A rs3783546 and rs3783521 were associated with an increased cancer risk in men, and IL1B rs3136558 and rs1143623 were associated with an decreased cancer risk in women. Meanwhile, rs3783550, rs3783546, rs1609682, and rs3783521 in IL1A were identified as biomarkers of risk among individuals aged ≤48 years. Rs3136558 and rs1143623 in the IL1B gene showed strong correlations with a susceptibility to thyroid cancer among individuals aged >48 years. Additionally, bioinformatics and eQTLs analysis also provided supporting evidence for the effects of the SNPs on gene regulation.

Our study is the first to report that IL1A and IL1B polymorphisms are risk factors for thyroid carcinoma in a Chinese Han population.