Null genotypes of GSTM1 and GSTT1 contribute to risk of cervical neoplasia: an evidence-based meta-analysis

• Published in: PloS one Vol. 6; no. 5; p. e20157
• Main Authors: Gao, Lin-Bo, Pan, Xin-Min, Li, Li-Juan, Liang, Wei-Bo, Bai, Peng, Rao, Li, Su, Xiao-Wei, Wang, Tao, Zhou, Bin, Wei, Yong-Gang, Zhang, Lin
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 23.05.2011; Public Library of Science (PLoS)
• Subjects: Biological products; Biology; Biomarkers; Blood cells; Carcinogens; Cervical cancer; Children & youth; Childrens health; Confidence intervals; Deoxyribonucleic acid; Detoxification; Developing countries; DNA; Female; Forensic pathology; Genetic aspects; Genetic Predisposition to Disease - genetics; Genotype; Genotypes; Genotyping; Glutathione; Glutathione transferase; Glutathione Transferase - genetics; Glutathione Transferase - metabolism; GSTM1 protein; GSTT1 protein; Head & neck cancer; Hospitals; Human papillomavirus; Humans; Identification methods; Laboratories; Laryngeal cancer; LDCs; Leukemia; Leukocytes; Medical prognosis; Medicine; Meta-analysis; Minority & ethnic groups; Odds Ratio; Oral cancer; Oxidative stress; Polymorphism, Genetic - genetics; Prostate cancer; Protein Binding - genetics; Protein Binding - physiology; Risk; Studies; Uterine Cervical Neoplasms - enzymology; Uterine Cervical Neoplasms - genetics; Womens health; China
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0020157

Glutathione S-transferases (GSTs) are multifunctional enzymes that play a key role in the detoxification of varieties of both endogenous products of oxidative stress and exogenous carcinogens. In this meta-analysis, twenty-five studies were identified by searching PubMed, EMBASE, ISI Web of Science and CBM databases: 23 evaluated GSTM1 and 19 evaluated GSTT1. Crude odds ratios with corresponding 95% confidence intervals were used to estimate the association between GSTM1 and GSTT1 polymorphisms and risk of cervical neoplasia. Subgroup analyses were conducted by pathological history, ethnicity, source of DNA for genotyping, quality score, and matching variable. The null genotypes of GSTM1 and GSTT1 polymorphisms were associated with a significantly increased risk of cervical neoplasia (for GSTM1: OR = 1.40; 95%CI, 1.19-1.65; for GSTT1: OR = 1.30; 95%CI, 1.05-1.62, respectively). Subgroup analyses showed that the null genotype of GSTM1 increased the risk of cervical neoplasia in Asians, studies with DNA isolation from white blood cells and tissue samples, both high and low quality studies, and matched studies. In GSTM1-GSTT1 interaction analysis, individuals with dual null genotype were associated with a significantly increased risk of cervical neoplasia (OR = 1.72; 95%CI, 1.18-2.51). These findings indicate that GSTM1 and GSTT1 polymorphisms, particularly GSTM1-GSTT1 interaction, may play critical roles in the development of cervical neoplasia. A conservative manner should be adopted to interpret these results because of obvious heterogeneity between-study, unadjusted data, and relatively small sample size in this meta-analysis. Well designed studies with larger sample size are of great value to confirm these results.