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Associations between UGT1A1*6 or UGT1A1*6/*28 polymorphisms and irinotecan-induced neutropenia in Asian cancer
Fei-fei Han1, Chang-long Guo, Dan Yu
1Pharmacy Department of Beijing Chao-Yang Hospital, Capital Medical University, 100020, Beijing, China, hanfeifei@163.com.
Purpose:
Neutropenia is a life-threatening side effect of irinotecan, and uridine diphosphate glucuronosyltransferases (UGTs) gene polymorphisms are considered to be one of the predictive markers of irinotecan-related toxicities. Many studies have demonstrated that patients bearing UGT1A1*28 have a higher risk of severe neutropenia on toxicity of irinotecan. However, UGT1A1 (TA7/TA7) was very rare in Asian populations. Some researches reported that UGT1A1*28 and/or UGT1A1*6 could predict irinotecan-induced toxicities in Asian populations, but controversial conclusions still remained. This study aims to investigate the association between UGT1A1 gene polymorphisms *6, *6/*28 and irinotecan-related neutropenia in Asian cancer patients receiving irinotecan regimen chemotherapy.
Experimental Design:
Meta-analyses were done to assess the relationship between UGT1A1*6 or UGT1A1*6/*28 and irinotecan-induced neutropenia.
Results:
The risk of neutropenia was significantly higher among patients with a UGT1A1*6 genotype than among those carrying the UGT1A1*1 allele(s) [odds ratio (OR) 3.276; 95 % confidence interval (CI) 1.887-5.688; P = 0.000 (*6/*6 vs. *1/*6 or *1/*1)], [OR 1.542; 95 % CI 1.180-2.041; P = 0.001 (*6/*6 or *1/*6 vs. *1/*1)]. Also, the risk was significantly higher among patients with a UGT1A1*6/*28 than among those carrying the UGT1A1*1 allele(s) [OR 3.275; 95 % CI 2.152-4.983; P = 0.000 (*6/*6 or *28/*28 or *6/*28 vs. *1/*6 or *1/*28 or *1/*1)].
Conclusions:
In conclusion, the UGT1A1*6 and UGT1A1*6/*28 genotypes were associated with an increased risk of irinotecan-induced neutropenia in Asian cancer patients.
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