MMP3 -1171 5A/6A Promoter Polymorphism Affects Level of Serum Major Histocompatibility Complex Class Chain Related B in Breast Cancer Patients

Background and Aims: Involvement of matrix metalloproteinases 3 (MMP3) in breast cancer tumor progression and metastasis has been revealed. MMP3 -1171 5A/6A and 5A/5A polymorphisms in the gene  promoter increase expression of the enzyme. The possible relationship of these polymorphisms and serum levels of major histocompatibility complex class I chain-related protein A and B (MICA/B) in breast cancer patients was goal of the study. Materials and Methods: In this case-control study, 105 breast cancer patients and 100 age-matched healthy women were selected. The MMP3-1171 5A/6A polymorphism was determined by nested and restriction fragment length polymorphism polymerase chain reaction. Concentration of MICB and MICA in serum of breast cancer patients has measured using enzyme-linked immunosorbent assay method. Results: Our results showed that 5A/5A + 6A/5A genotypes in the breast cancer group (77.18%) were more frequent compared to healthy participants (64%). However, the frequency of MMP3 -1171 5A/6A genotypes in the breast cancer patients and healthy donors was similar. Additionally, in the patients with 5A/6A genotypes, the mean of MICB concentration was 51.3±16 pg/ml whereas; in the homozygote 6A/6A genotype, it was 4.7±2.6 pg/ml. Statistical analysis confirmed a significant difference between MMP3 -1171 5A/6A and serum MICB levels in the patients (p=0.02). Based on our results MMP3-1171 5A/6A polymorphism did not alter MICA concentration in the patients (p=0.15) Conclusions: The MMP3 -1171 5A/6A genotype might be associated with shedding of MICB in breast cancer patients.