Study of MDR1 C1236T Polymorphism in patients with Breast Cancer and Relationship with Response to Treatment in Women

Background: Multidrug resistance is the main cause of unsuccessful chemotherapy. The most important reason of drug resistance is ATP dependent pumps such as MDR1 gene that extrude drugs from the cell. MDR1 gene encodes p-glycoprotein (P-gp), a transmembrane glycoprotein that transports many hydrophobic substrates and anti-cancer drugs out of the cell. This geneis highly polymorphic and it seems that these polymorphisms influence the gene expression and response to treatment. The aim of this study was to investigate MDR1 gene C1236T polymorphism and its association with response to treatment in patients with breast cancer.Materials & Methods: A number of 50 patients and 50 control persons were selected in city of Kerman. 5 ml of blood was sampled from everybody and immediately kept in -80° C until use. DNA samples were extracted by standard salting out extraction method. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used for the detection of 1236T single nucleotide polymorphism. Results were analyzed by SPSS software using Chi-square test and P value < 0/05 was considered statistically significant.Results: The results showed that CC, CT and TT genotype frequencies in breast cancer patients as 16%, 32%and 52%, respectively. In the control group, frequencies of genotypes were found as 10% for CC, 36% for CT and 48% for TT. Also the results showed that CC, CT and TT genotype frequencies in responder to treatment as 10/81%, 24/32% and 64/86% , respectively. In the non-responder patients to treatment, these values were found as 30/76% for CC, 53/84% for CT and 15/38% for TT.Conclusion: There was no significant difference in frequencies of C1236T polymorphism between patients and control group (p = 0/317). Also this results showed that there was significant difference frequencies of C1236T polymorphism between responders and non- responders (p = 0/004).

کلیدواژه ها:

Breast Cancer ، Polymorphism ، Multi Drug Resistance ، PCR-RFLP