CXCL12/CXCR4 Gene Polymorphism as a Putative Prognostic Factor for Metastasizing Breast Cancer Under Chemotherapy

 C-X-C motif chemokine ligand 12 (CXCL12; known as stromal cell-derived factor 1 [SDF-1]) and its receptor C-X-C chemokine receptor 4 (CXCR4) are 2 pairs studied in breast cancer metastasis. This study aimed to investigate the relationship between the occurrence of CXCL4 and CXCL12 gene polymorphisms and the clinical and pathological characteristics of patients with metastatic breast cancer under chemotherapy.

 Genomic DNA was extracted from the blood samples of 30 patients with metastatic breast cancer and 30 control samples. The polymorphisms of CXCL12 and CXCR4 were detected using the tetra-primer amplification refractory mutation system–polymerase chain reaction (T-ARMS–PCR) method. The results were analyzed using SPSS version 20 with a 95% CI.

 The mean age of the patients was 50 years, and the average age of the healthy subjects was 41.23 years. The disease was diagnosed in 63.33% of the cases before menopause and in 36.66% after menopause. Also, 73.32% of patients showed metastatic signs 3-6 years after primary chemotherapy, and 63.33% of all patients had a grade III tumor. There was a significant relationship between the time of relapse after chemotherapy and the occurrence of polymorphisms (P = 0.001), between age and incidence (P = 0.02), and between menopausal age and incidence (P = 0.07).

 No significant correlation was found between the occurrence of mutant alleles of CXCL12 and CXCR4 polymorphisms and breast cancer. The relapse of the disease after chemotherapy and the age of menopause are associated with the occurrence of polymorphisms. However, further studies are needed to confirm the results.