Study of MDR1 C3435T Polymorphism in patients with Breast Cancer in Women

Background: One of the limitations in the treatment of cancer patients with chemotherapy is the development of multidrug resistance (MDR). The multidrug resistance (MDR) 1 gene encodes a 170-kDa membrane transporter called P-glycoprotein, which P-gp is a member of the ABC family of transporters that extrudes various hydrophobic drugs and peptides from the inside to the outside of the plasma membrane by the way of an ATP-dependent cellular efflux mechanism. MDR1 gene polymorphisms could alter the expression level of P-gp and consequently result in drug resistance. The aim of this study was to investigate MDR1 gene C3435T polymorphism. 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 C3435T 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 CC, CT and TT genotype frequencies in breast cancer patients as 14%, 56% and 30%, respectively. In the control group, genotype frequencies were found as 22% for CC, 52% for CT and 26% for TT. The C allele frequency was found in 42% and the T allele frequency was found in 58% patients. In control group the C allele frequency was found in 48% and the T allele frequency was found in 52%.Conclusion: There was no significant difference in genotype frequencies of C3435T polymorphism between patients and control group (p = 0/373). Also there was no significant difference in allele frequencies of C3435T polymorphism between patients and control group (p = 0/420).

Keywords:

Breast Cancer , Polymorphism , Multi Drug Resistance , PCR-RFLP , C3435T