Genetic polymorphisms of superoxide dismutase-1 A251G and catalase C-262T with the risk of colorectal cancer.

Oxidative stress is significant in numerous types of disease including cancer. To protect cells and organs against reactive oxygen species (ROS), the body has evolved an antioxidant protection system that involved in the detoxification of ROS. Single nucleotide polymorphisms (SNP) of anti-oxidative enzymes may dramatically change the activity of the encoded proteins; therefore, certain alleles can be established as risk factors for some kind of multi-factorial diseases including cancer.

Susceptibility to Colorectal Cancer and Two Genetic Polymorphisms of XRCC4.

The X-ray complementing group 4 (XRCC4, OMIM: 194363) plays a key role in non-homologous end-joining DNA repair pathway in mammalian cells. This pathway is believed to help maintain genomic stability. In the present study, it is hypothesized that genetic polymorphisms in the NHEJ repair XRCC4 gene may be associated with an increased risk in developing colorectal cancer (CRC).

Association between polymorphisms at promoters of XRCC5 and XRCC6 genes and risk of breast cancer.

Variation in DNA repair genes is one of the mechanisms that may lead to variation in DNA repair capacity. Ku, a heterodimeric DNA-binding complex, is directly involved in repair of DNA double-strand breaks. Ku consists of two subunits, Ku70 and Ku80, which are encoded by the XRCC6 and XRCC5 genes, respectively.

Genetic variation in DNA repair gene XRCC7 (G6721T) and susceptibility to breast cancer.

The human XRCC7 is a DNA double-strand break (DSBs) repair gene, involved in non-homologous end joining (NHEJ). It is speculated that DNA DSBs repair have an important role during development of breast cancer. The human XRCC7 is a NHEJ DSBs repair gene.

Clinical response to chemotherapy in locally advanced breast cancer was not associated with several polymorphisms in detoxification enzymes and DNA repair genes.

The main aim of the present study was to investigate the association between several genetic polymorphisms (in glutathione S-transferase members and DNA repair genes) and clinical response to chemotherapy in locally advanced breast cancer. A sequential series of 101 patients were prospectively included in this study. Clinical assessment of treatment was accomplished by comparing initial tumor size with preoperative tumor size using revised RECIST guideline (version 1.

Susceptibility to breast cancer and three polymorphisms of GSTZ1.

Glutathione S-transferases class zeta (GSTζ) is involved in the detoxification of xenobiotic compounds and catalyzes the biotransformation of a variety of α-haloacids including dichloroacetic acid and chlorofluoroacetic acid. It has been reported that, in mice, deficiency of Gstz1 (a member of GSTζ) resulted in the generation of a constant level of oxidative stress. The present study was carried out to investigate the association between genetic polymorphisms of GSTZ1 (in promoter site G-1002A and in coding sites Glu32Lys and Gly42Arg) and risk of breast cancer.

Parental consanguineous marriages and clinical response to chemotherapy in locally advanced breast cancer patients.

The main aim of the present study was investigating the association between parental consanguinity and clinical response to chemotherapy in females affected with locally advanced breast cancer. A consecutive series of 92 patients were prospectively included in this study. Clinical assessment of treatment was accomplished by comparing initial tumor size with preoperative tumor size using revised RECIST guideline (version 1.

Association between N142D genetic polymorphism of GSTO2 and susceptibility to colorectal cancer.

Expression pattern analysis has been revealed that glutathione S-transferase omega 2 (GSTO2, a member of class omega) is ubiquitously expressed. Over expression of GSTO2 induced apoptosis. The gene encoding GSTO2 was localized to human chromosome 10q24.

Genetic polymorphisms of GSTO2, GSTM1, and GSTT1 and risk of gastric cancer.

Objective: The glutathione S-transferases (GSTs) are a superfamily of proteins that participates in detoxification. The GSTs were dividing into several classes including omega (GSTO), micro (GSTM) and theta (GSTT) classes. In human GSTO2, GSTM1, and GSTT1 are polymorphic.

Genetic polymorphisms of XRCC1 (codon 399) and susceptibility to breast cancer in Iranian women, a case-control study.

The X-ray repair cross-complementation group 1 (XRCC1) protein plays an important role in base excision repair. In the present study, we specifically investigated whether common genetic variant in XRCC1 (exon 10, codon Arg399Gln) was associated with an altered risk of breast cancer. The eligible cases were patients at chemotherapy unit of Nemazi hospital, Shiraz Iran, from October 1999 to August 2000 and from July 2004 to July 2005.