Role of polymorphisms of GSTM1, GSTT1 and GSTP1 Ile105Val in childhood acute lymphoblastic leukemia risk: an updated meta-analysis.
BACKGROUND
The association between glutathione-S-transferase polymorphisms (GSTM1, GSTT1 and GSTP1 Ile105Val) and risk of childhood acute lymphoblastic leukemia (ALL) remains controversial. Therefore, we performed a meta-analysis to derive a more precise estimation of the relationship.


METHODS
We searched Medline (Mainly Pubmed), Embase, Cochrane Library, CNKI (Chinese National Knowledge Infrastructure), Chinese Biomedical Literature (Chinese) and Wanfang (Chinese) Databases to collect articles that evaluated the polymorphism of GSTs gene in child patients with ALL. We also reviewed reference lists from retrieved articles. Two researchers evaluated study eligibility and extracted the data independently, and disagreements were resolved by discussion. Two reviewers independently assessed the methodological quality of each study. The principal outcome measure was the odds ratio (OR) with 95% conﬁdence interval (CI) for the risk of child ALL associated with GSTM1, GSTT1, GSTP1 Ile105Val. The data were analyzed using Stata (Version 12.0) software.


RESULTS
This meta-analysis included 30 studies for GSTM1 polymorphism, 27 studies for GSTM1 polymorphism and 10 studies for GSTP1 Ile105Val polymorphism. The combined results based on all studies showed that GSTM1 (OR= 1.297, 95% CI= 1.105-1.523, P=0.001) and GSTT1 polymorphism (OR=1.213, 95% CI=1.031-1.427, P= 020) contributes to the development of childhood ALL, while no association was found in all comparison models of GSTP1 Ile105Val variants (homozygote model: OR=1.234, 95% CI=0.966-1.578, P=0.093, heterozygote model: OR=1.072, 95% CI=0.931-1.235, P=0.331, dominant model: OR=1.104, 95% CI=0.965-1.262, P=0.149, recessive model: OR=1.184, 95% CI=0.934-1.499, P=0.162, and allele comparison model: OR=1.096, 95% CI=0.988-1.216, P=0.083).


CONCLUSIONS
The current analyses suggests significant association was found between GSTM1 variants and the risk of childhood ALL, while no association were found between GSTT1 and GSTP1 Ile105Val polymorphism and childhood ALL risk.
Department of Pediatric Surgery, Linyi Peoples' Hospital, Linyi, China.
Tao
T
Zhao
Department of Pediatric Surgery, Linyi Peoples' Hospital, Linyi, China.
Fenglian
F
Ma
Department of Pediatric Surgery, Linyi Peoples' Hospital, Linyi, China - fangqing_yin@sina.com.
Fangqing
F
Yin
D002648:Child; D020022:Genetic Predisposition to Disease; D051549:Glutathione S-Transferase pi / Q000235:genetics*; D005982:Glutathione Transferase / Q000235:genetics*; D006801:Humans; D011110:Polymorphism, Genetic; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000235:genetics* / Q000473:pathology; D012307:Risk Factors
D051549:Glutathione S-Transferase pi; D005982:Glutathione Transferase; C413545:glutathione S-transferase T1; C496556:GSTP1 protein, human