title: Effect of MDR1 polymorphism on multidrug resistance expression in breast cancer patients.
abstract: One of the limitations in the treatment of cancer patients with chemotherapy is the development of multidrug resistance (MDR). A well-known mechanism responsible for drug resistance is over-expression of ABC-transporter genes such as MDR1. This gene encodes p-glycoprotein (P-gp), a transmembrane glycoprotein that transports many hydrophobic substrates and anti-cancer drugs out of the cell. MDR1 gene polymorphisms could alter the expression level of P-gp and consequently result in drug resistance. We investigated a possible association between MDR1 gene C3435T polymorphism and its expression in Iranian breast cancer patients. PCR-RFLP was used for the detection of C3435T single nucleotide polymorphism in 54 breast cancer patients and 50 healthy individuals. The expression level of MDR1 was determined by real-time quantitative PCR. We observed no difference in the frequency of C3435T polymorphism between breast cancer patients and healthy controls. However, there was a significant association between MDR1 expression levels and C3435T polymorphism in the patients. C3435T polymorphism may play a role in inducing drug resistance by altering the expression level of the MDR1 gene.
authors.affiliation: Departament of Clinical Genetics, National Institute of Genetic Engineering and Biotechnology, Tehran, Iran.
authors.forename: M
authors.initials: M
authors.lastname: Taheri
authors.forename: F
authors.initials: F
authors.lastname: Mahjoubi
authors.forename: R
authors.initials: R
authors.lastname: Omranipour
mesh_terms: D018435:ATP Binding Cassette Transporter, Subfamily B; D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000235:genetics*; D000328:Adult; D001943:Breast Neoplasms / Q000235:genetics*; D018432:Drug Resistance, Multiple / Q000235:genetics*; D019008:Drug Resistance, Neoplasm / Q000235:genetics*; D005260:Female; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D007492:Iran; D008875:Middle Aged; D011110:Polymorphism, Genetic
chemical_list: C513055:ABCB1 protein, human; D018435:ATP Binding Cassette Transporter, Subfamily B; D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1