Association of SNP-SNP Interactions Between RANKL, OPG, CHI3L1, and VDR Genes With Breast Cancer Risk in Egyptian Women

Clin Breast Cancer. 2019 Feb;19(1):e220-e238. doi: 10.1016/j.clbc.2018.09.004. Epub 2018 Sep 19.

Abstract

Background: Genetic susceptibility for breast cancer (BC) is still poorly understood. A combination of multiple low-penetrant alleles of cancer-related genes and gene-gene interactions (epistasis) contributes to BC risk. Genetic variants in receptor activator of nuclear factor κB ligand (RANKL), osteoprotegerin (OPG), chitinase-3-like protein 1 (CHI3L1), and vitamin D receptor (VDR) genes are implicated in breast carcinogenesis; however, the influence of their epistatic effects on BC susceptibility has not yet been studied. We investigated the association of single nucleotide polymorphism (SNP)-SNP interactions and haplotypes of 6 SNPs in these 4 genes with the genetic predisposition of BC in Egyptian women.

Patients and methods: Data of 115 BC patients and 120 cancer-free controls were studied. Association tests were conducted using logistic regression models.

Results: Individual SNPs showed weak statistical significance with BC susceptibility. The interactions between RANKL-rs9533156 and OPG-rs2073618; OPG-rs2073618 with CHI3L1-rs4950928, VDR-rs2228570 and VDR-rs1544410; OPG-rs2073617 and VDR-rs1544410; VDR-rs2228570 and VDR-rs1544410 were strongly associated with increased BC risk after adjustment for multiple comparisons. No SNPs were in strong linkage disequilibrium. The TCTCTG-rs9533156-rs2073618-rs2073617-rs4950928-rs2228570-rs1544410 haplotype was significantly associated with increased BC risk (adjusted odds ratio = 8.33; 95% confidence interval, 1.32-52.46; P = .025) compared with controls. TCCCTG haplotype stratified BC patients according to estrogen receptor/progesterone receptor status. TCTCTA was positively associated, and TCTCTG and TGTCTG haplotypes inversely correlated with bone metastasis. Bioinformatic analysis revealed 13 proteins commonly interacting with our 4 genes; the most significant was signal transducer and activator of transcription 5B.

Conclusion: Our results suggested that a stronger combined effect of SNPs in RANKL, OPG, CHI3L1, and VDR genes via gene-gene interaction may help predict BC risk and prognosis.

Keywords: Epistasis; Gene–gene interaction; Haplotype; Metastasis; Polymorphism.

MeSH terms

  • Adult
  • Aged
  • Breast Neoplasms / epidemiology
  • Breast Neoplasms / genetics*
  • Breast Neoplasms / pathology
  • Carcinoma, Ductal, Breast / epidemiology
  • Carcinoma, Ductal, Breast / genetics
  • Carcinoma, Ductal, Breast / secondary
  • Carcinoma, Lobular / epidemiology
  • Carcinoma, Lobular / genetics
  • Carcinoma, Lobular / secondary
  • Case-Control Studies
  • Chitinase-3-Like Protein 1 / genetics*
  • Egypt / epidemiology
  • Female
  • Follow-Up Studies
  • Genetic Predisposition to Disease
  • Humans
  • Lymphatic Metastasis
  • Middle Aged
  • Osteoprotegerin / genetics*
  • Polymorphism, Single Nucleotide*
  • Prognosis
  • RANK Ligand / genetics*
  • Receptors, Calcitriol / genetics*
  • Retrospective Studies
  • Risk Factors

Substances

  • CHI3L1 protein, human
  • Chitinase-3-Like Protein 1
  • Osteoprotegerin
  • RANK Ligand
  • Receptors, Calcitriol
  • TNFRSF11B protein, human
  • TNFSF11 protein, human
  • VDR protein, human