title: Genotype frequencies of selected drug metabolizing enzymes and ABC drug transporters among breast cancer patients on FAC chemotherapy.
abstract: Polymorphic genes of drug metabolizing enzymes and transporters may influence drug response. With some exemptions, single nucleotide polymorphisms in such genes, however, are not known to be susceptibility factors for breast cancer. This study explored genotype profiles for the breast cancer patients on fluorouracil, doxorubicin and cyclophosphamide (FAC) in a Pakistani set of population and their comparison with HapMap data. Sixty-eight female breast cancer patients were included. All received FAC chemotherapy. Relevant genotyping was done either through restriction fragment length polymorphism or pyrosequencing. The variant allele frequencies were: 5.1% for CYP2C9*2 (430C>T), 15.4% for CYP2C9*3 (1075A>C), 27.2% for CYP2C19*2 (681G>A), 33.1% for GSTA1*B (-69C>T, -52G>A), 62.5% for ALDH3A1*2 (985C>G), 58.8% and 4.4% for ABCB1 (2677 G>T/A), 64.7% for ABCB1 3435 C>T, and 15.4%, 33.1% and 39.7% for ABCC2 (-24 C>T, 1249 G>A and 3972 C>T). In comparison with HapMap, this first exploration in Pakistani samples shows higher frequency of (i) CYP2C9*3 carriers (p < 0.05) than in Hispanic, Chinese, Japanese and African samples, (ii) ALDH3A1*2 carriers (p < 0.01) than Caucasian, Hispanic, Chinese, Japanese and African samples. For ABC transporters, a higher frequency of variant allele was observed in (iii) ABCB1 2677 G>T/A (p < 0.01) than Caucasian, Hispanic and African, (iv) ABCB1 3435 C>T (p < 0.05) than Chinese, Japanese and African, (v) ABCC2 1249 G>A (p < 0.01) than Hispanic, Chinese and Japanese samples. In conclusion, cyclophosphamide activation and detoxification of reactive intermediates may be altered in the Pakistani. Though carriers of CYP2C19*2 were higher than in Caucasian and Hispanics, they did not reach statistical significance (p = 0.05).
authors.affiliation: Ziauddin University, Clifton Campus, Shahra-e-Ghalib, Karachi, Pakistan. drnasirpk@yahoo.com
authors.forename: Nasir Ali
authors.initials: NA
authors.lastname: Afsar
authors.forename: Sierk
authors.initials: S
authors.lastname: Haenisch
authors.forename: Ahmed
authors.initials: A
authors.lastname: Mateen
authors.forename: Ahmed
authors.initials: A
authors.lastname: Usman
authors.forename: Mike
authors.initials: M
authors.lastname: Ufer
authors.forename: Khwaja Zafar
authors.initials: KZ
authors.lastname: Ahmed
authors.forename: Hakimuddin Razi
authors.initials: HR
authors.lastname: Ahmad
authors.forename: Ingolf
authors.initials: I
authors.lastname: Cascorbi
mesh_terms: D018435:ATP Binding Cassette Transporter, Subfamily B; D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000235:genetics / Q000378:metabolism; D018528:ATP-Binding Cassette Transporters / Q000235:genetics* / Q000378:metabolism; D000444:Aldehyde Dehydrogenase / Q000235:genetics / Q000378:metabolism; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000493:pharmacokinetics* / Q000627:therapeutic use; D001189:Aryl Hydrocarbon Hydroxylases / Q000235:genetics / Q000378:metabolism; D001943:Breast Neoplasms / Q000188:drug therapy / Q000235:genetics* / Q000378:metabolism; D018270:Carcinoma, Ductal, Breast / Q000188:drug therapy / Q000235:genetics* / Q000378:metabolism; D003520:Cyclophosphamide / Q000493:pharmacokinetics / Q000627:therapeutic use; D065729:Cytochrome P-450 CYP2C9; D004252:DNA Mutational Analysis; D004317:Doxorubicin / Q000493:pharmacokinetics / Q000627:therapeutic use; D005260:Female; D005472:Fluorouracil / Q000493:pharmacokinetics / Q000627:therapeutic use; D005787:Gene Frequency; D005838:Genotype; D005982:Glutathione Transferase / Q000235:genetics / Q000378:metabolism; D006801:Humans; D008658:Inactivation, Metabolic; D000089762:Multidrug Resistance-Associated Protein 2; D010154:Pakistan; D011110:Polymorphism, Genetic; D012150:Polymorphism, Restriction Fragment Length; D044469:Racial Groups / Q000235:genetics
chemical_list: C513055:ABCB1 protein, human; C000715087:ABCC2 protein, human; D018435:ATP Binding Cassette Transporter, Subfamily B; D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D018528:ATP-Binding Cassette Transporters; D000089762:Multidrug Resistance-Associated Protein 2; D004317:Doxorubicin; D003520:Cyclophosphamide; C450260:CYP2C9 protein, human; D065729:Cytochrome P-450 CYP2C9; D001189:Aryl Hydrocarbon Hydroxylases; C480021:ALDH3A1 protein, human; D000444:Aldehyde Dehydrogenase; C484555:GSTA1 protein, human; D005982:Glutathione Transferase; D005472:Fluorouracil