Role of Irisin/FNDC5 (rs3480) Single Nucleotide Polymorphism in Breast Cancer.

Background: Breast cancer is the most common malignancy among women
and remains a leading cause of cancer-related mortality. Previous studies
suggest that the FNDC5/irisin gene may exert a protective role against breast
cancer, as reduced expression levels have been linked to the presence of
metastasis. The present study aims to investigate the potential association
between single nucleotide polymorphisms (SNPs) in the irisin gene and the risk
of breast cancer. In addition, it will analyze the distribution of these genetic
alleles in relation to different clinical parameters of the disease
Patients & Methods: This cross-sectional study was conducted from July 2023
to May 2024 and included 50 pathologically confirmed breast cancer patients
recruited from the Clinical Oncology Department, Faculty of Medicine, Sohag
University. A control group of 50 healthy volunteers, with no clinical evidence
of any neoplastic disorder, was also enrolled. Patient characteristics were
retrieved from the local databases of the Clinical Oncology Department at
Sohag University.
Results: Our study revealed no significant differences between cases and
controls regarding age or family history. Circulating irisin levels showed a
highly significant reduction in breast cancer patients compared to controls (P <
0.001). In addition, a statistically significant association was identified between
genotypic distribution and tumor pathology (P < 0.005). The GG genotype was
predominantly linked to invasive lobular carcinoma (33.3%), whereas the AA
and AG genotypes were more frequently associated with invasive ductal
carcinoma
Conclusion: The study concluded that circulating irisin appears to play a
protective role against breast cancer, as its levels were markedly lower in
patients compared to controls. While irisin gene polymorphism may not
represent a direct risk factor for breast cancer, it could influence tumor behavior
of breast cancer and disease severity.