Associations between UGT1A1*6 or UGT1A1*6/*28 polymorphisms and irinotecan-induced neutropenia in Asian cancer patients

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.     

UGT1A1*28 genotype and irinotecan-induced neutropenia: dose matters

The Food and Drug Administration and Pfizer changed the package insert for irinotecan to include a patient's UGT1A1*28 genotype as a risk factor for severe neutropenia on the basis of the findings of four pharmacogenetic studies, which found that irinotecan-treated patients who were homozygous for the UGT1A1*28 allele had a greater risk of hematologic toxic effects than patients who had one or two copies of the wild-type allele (UGT1A1*1). Findings of subsequent irinotecan pharmacogenetic studies have been inconsistent. In a meta-analysis, we reviewed data presented in nine studies that included a total of 10 sets of patients (for a total of 821 patients) and assessed the association of irinotecan dose with the risk of irinotecan-related hematologic toxicities (grade III-IV) for patients with a UGT1A1*28/*28 genotype. The risk of toxicity was higher among patients with a UGT1A1*28/*28 genotype than among those with a UGT1A1*1/*1 or UGT1A1*1/*28 genotype at both medium (odds ratio [OR] = 3.22, 95% confidence interval [CI] = 1.52 to 6.81; P = .008) and high (OR = 27.8, 95% CI = 4.0 to 195; P = .005) doses of irinotecan. However, risk was similar at lower doses (OR = 1.80, 95% CI = 0.37 to 8.84; P = .41). Low doses of irinotecan (100-125 mg/m2) are in the commonly used therapeutic range. The risk of experiencing irinotecan-induced hematologic toxicity for patients with a UGT1A1*28/*28 genotype thus appears to be a function of the dose of irinotecan administered.     

Genotype-directed, dose-finding study of irinotecan in cancer patients with UGT1A1*28 and/or UGT1A1*6 polymorphisms

Irinotecan-induced severe neutropenia is associated with homozygosity for the UGT1A1*28 or UGT1A1*6 alleles. In this study, we determined the maximum-tolerated dose (MTD) of irinotecan in patients with UGT1A1 polymorphisms. Patients who had received chemotherapy other than irinotecan for metastatic gastrointestinal cancer were enrolled. Patients were divided into three groups according to UGT1A1 genotypes: wild-type (*1/*1); heterozygous (*28/*1, *6/*1); or homozygous (*28/*28, *6/*6, *28/*6). Irinotecan was given every 2 weeks for two cycles. The wild-type group received a fixed dose of irinotecan (150 mg/m(2)) to serve as a reference. The MTD was guided from 75 to 150 mg/m(2) by the continual reassessment method in the heterozygous and homozygous groups. Dose-limiting toxicity (DLT) and pharmacokinetics were evaluated during cycle 1. Of 82 patients enrolled, DLT was assessable in 79 patients (wild-type, 40; heterozygous, 20; and homozygous, 19). Dose-limiting toxicity occurred in one patient in the wild-type group, none in the heterozygous group, and six patients (grade 4 neutropenia) in the homozygous group. In the homozygous group, the MTD was 150 mg/m(2) and the probability of DLT was 37.4%. The second cycle was delayed because of neutropenia in 56.3% of the patients given the MTD. The AUC(0-24 h) of SN-38 was significantly greater (P < 0.001) and more widely distributed in the homozygous group. Patients homozygous for the UGT1A1*28 or UGT1A1*6 allele can receive irinotecan in a starting dose of 150 mg/m(2), but many required dose reductions or delayed treatment in subsequent cycles. UMIN Clinical Trial Registration number: UMIN000000618.     

UGT1A1*28 polymorphism predicts irinotecan-induced severe toxicities without affecting treatment outcome and survival in patients with metastatic colorectal carcinoma

BACKGROUND: It is known that the uridine-diphosphoglucuronosyl transferase 1A1 (UGT1A1)*28 polymorphism reduces UGT1A1 enzyme activity, which may lead to severe toxicities in patients who receive irinotecan. This study was conducted to assess the influence of this polymorphism on the efficacy and toxicity of irinotecan treatment in Chinese patients with metastatic colorectal carcinoma (CRC). METHODS: In total, 128 patients with metastatic CRC who had received previous treatment with irinotecan plus 5-fluorouracil/leucovorin were analyzed retrospectively. Genomic DNA samples were obtained from patients' leukocytes, and genotypes were determined by analyzing the sequence of TATA boxes in the UGT1A1 gene. The influence of the UGT1A1*28 polymorphism on toxicity and treatment outcome was analyzed. RESULTS: Approximately 20% of patients were identified with the UGT1A1*28 polymorphism, including 15.6% (n = 20 patients) with the thymine-adenine (TA)6/TA7 genotype and 4.7% (n = 6 patients) with the TA7/TA7 genotype. The remaining 79.7% of patients (n = 102) had wild type TA6/TA6. Marked increases in grade 3 or 4 neutropenia (53.8% vs 4.9%; P < .01), neutropenic fever (38.5% vs 3.9%; P < .01), diarrhea (26.9% vs 5.9%; P < .01), and pretreatment bilirubin level (23.1% vs 8.8%; P = .04) were observed in patients who had the TA6/TA7 or TA7/TA7 genotypes. Patients' pretreatment bilirubin levels correlated well with irinotecan-induced neutropenia (P < .01). It was noted that, although the requirement for irinotecan dose reduction was significantly greater in patients who had this genetic variant (42.3% vs 12.7%; P < .01), it did not affect the response rate to irinotecan-based chemotherapy (42.3% vs 45.1%; P = .80), and it did not significantly affect progression-free survival (10 months vs 11 months; P = .94) or overall survival (19 months vs 18 months; P = .84). CONCLUSIONS: The current data suggested that the UGT1A1*28 polymorphism may be a key determinant for predicting irinotecan-induced severe toxicities without affecting treatment outcome for patients with metastatic CRC. Further prospective studies are warranted for using this polymorphism to optimize irinotecan-based chemotherapy.     

UGT1A and TYMS genetic variants predict toxicity and response of colorectal cancer patients treated with first-line irinotecan and fluorouracil combination therapy

Background:

The impact of thymidylate synthase (TYMS) and UDP-glucoronosyltransferase 1A (UGT1A) germline polymorphisms on the outcome of colorectal cancer (CRC) patients treated with irinotecan plus 5-fluorouracil (irinotecan/5FU) is still controversial. Our objective was to define a genetic-based algorithm to select patients to be treated with irinotecan/5FU.

Methods:

Genotyping of TYMS (5′TRP and 3′UTR), UGT1A1^*28, UGT1A9^*22 and UGT1A7^*3 was performed in 149 metastatic CRC patients treated with irinotecan/5FU as first-line chemotherapy enrolled in a randomised phase 3 study. Their association with response, toxicity and survival was investigated by univariate and multivariate statistical analysis.

Results:

TYMS 3TRP/3TRP genotype was the only independent predictor of tumour response (OR=5.87, 95% confidence interval (CI)=1.68–20.45; P=0.005). UGT1A1^*28/^*28 was predictive for haematologic toxicity (OR=6.27, 95% CI=1.09–36.12; P=0.04), specifically for neutropenia alone (OR=6.40, 95% CI=1.11–37.03; P=0.038) or together with diarrhoea (OR=18.87, 95% CI=2.14–166.67; P=0.008). UGT1A9^*1/^*1 was associated with non-haematologic toxicity (OR=2.70, 95% CI=1.07–6.82; P=0.035). Haplotype VII (all non-favourable alleles) was associated with non-haematologic toxicity (OR=2.11, 95% CI=1.12–3.98; P=0.02).

Conclusion:

TYMS and UGT1A polymorphisms influence on tumour response and toxicities derived from irinotecan/5FU treatment in CRC patients. A genetic-based algorithm to optimise treatment individualisation is proposed.     

UGT1A1 gene variations and irinotecan treatment in patients with metastatic colorectal cancer

SN-38 is the active metabolite of irinotecan and it is metabolised through conjugation by uridine diphosphate glucuronosyl transferase (UGT1A1). The major toxicity of irinotecan therapy is diarrhoea, which has been related to the enzymatic activity of UGT1A1. We examined the influence of the UGT1A1 gene promoter polymorphism in the toxicity profile, in the response rate and in the overall survival (OS) in 95 patients with metastatic colorectal cancer treated with an irinotecan-containing chemotherapy. Genotypes were determined by analysing the sequence of TATA box of UGT1A1 of genomic DNA from the patients. Clinical parameters and genotypes were compared by univariate and multivariate statistical methods. The more frequent adverse effects were asthenia (34 patients), diarrhoea (29 patients) and neutropenia (20 patients). Severe diarrhoea was observed in 7/10 homozygous (70%) and 15/45 heterozygous (33%) in comparison to 7/40 (17%) wild-type patients (P=0.005). These results maintained the statistical significance in logistic regression analysis (P=0.01) after adjustment for other clinical relevant variables. The presence of severe haematological toxicity increased from wild-type patients to UGT1A1(*)28 homozygotes, but without achieving statistical significance. No relationship was found between the UGT1A1(*)28 genotypes and infection, nausea or mucositis. In univariate studies, patients with the UGT1A1(*)28 polymorphism showed a trend to a poorer OS (P=0.09). In the multivariate analysis, the genotype was not related to clinical response or to OS. The role of the UGT1A1 genotype as a predictor of toxicity in cancer patients receiving irinotecan demands the performance of a randomized trial to ascertain whether genotype-adjusted dosages of the drug can help to establish safe and effective doses not only for patients with the UGT1A1(*)28 homozygous genotype but also for those with the most common UGT1A1 6/6 or 6/7 genotype.     

Integrated pharmacogenetic prediction of irinotecan pharmacokinetics and toxicity in patients with advanced non-small cell lung cancer

To define an integrated pharmacogenetic model for predicting irinotecan pharmacokinetic (PK) and severe toxicity, we evaluated multivariate analysis using 15 polymorphisms within seven genes with putative influence on metabolism and transport of irinotecan. A total of 107 NSCLC patients treated with irinotecan were evaluated for PK and genotyped for the UGT1A1*6, UGT1A1*28, UGT1A9*22, ABCB11236C>T, 2677G>T/A, 3435C>T, ABCC2-24C>T, 1249G>A, 3972C>T, ABCG234G>A, 421C>A, and SLCO1B1 -11187G>A, 388A>G, and 521T>C, and CYP3A5*3 polymorphisms. Multivariate linear and logistic regression analyses including genotypes and clinicopathologic factors were performed. SN-38 AUC was significantly correlated with ANCs (r=-0.3, p=0.009) and grade 4 neutropenia (p=0.01). The UGT1A1*6/*6, UGT1A9*1/*1 or *1/*22, and SLCO1B1 521TC or CC genotypes, and female-gender were predictive for higher AUC(SN-38) in multivariate analysis. Among them, SLCO1B1 521TC or CC and UGT1A1*6/*6 genotypes were independently predictive for grade 4 neutropenia in multivariate analysis (OR=3.8 and 7.4, respectively). Although no significant association was observed between PK parameters and grade 3 diarrhea, UGT1A9*1/*1, ABCC23972CC, and ABCG234GA or AA genotypes were independently predictive for grade 3 diarrhea in multivariate analysis (OR=6.3, 5.6, and 5.1, respectively). Patient selection based on integrated pharmacogenetic model would be helpful for predicting irinotecan-PK and severe toxicities in NSCLC patients.     

UGT1A1*28 genotype and irinotecan dosage in patients with metastatic colorectal cancer: a Dutch Colorectal Cancer Group study

The aim of the study was to investigate the associations between UGT1A1(*)28 genotype and (1) response rates, (2) febrile neutropenia and (3) dose intensity in patients with metastatic colorectal cancer treated with irinotecan. UGT1A1(*)28 genotype was determined in 218 patients receiving irinotecan (either first-line therapy with capecitabine or second-line as monotherapy) for metastatic colorectal cancer. TA(7) homozygotes receiving irinotecan combination therapy had a higher incidence of febrile neutropenia (18.2%) compared to the other genotypes (TA(6)/TA(6) : 1.5%; TA(6)/TA(7) : 6.5%, P=0.031). TA(7) heterozygotes receiving irinotecan monotherapy also suffered more febrile neutropenia (19.4%) compared to TA(6)/TA(6) genotype (2.2%; P=0.015). Response rates among genotypes were not different for both regimens: combination regimen, P=0.537; single-agent, P=0.595. TA(7) homozygotes did not receive a lower median irinotecan dose, number of cycles (P-values >or=0.25) or more frequent dose reductions compared to the other genotypes (P-values for trend; combination therapy: 0.62 and single-agent: 0.45). Reductions were mainly (>80%) owing to grade >or=3 diarrhoea, not (febrile) neutropenia. TA(7)/TA(7) patients have a higher incidence of febrile neutropenia upon irinotecan treatment, but were able to receive similar dose and number of cycles compared to other genotypes. Response rates were not significantly different.     

中国人尿苷二磷酸葡糖苷酸转移酶1A基因多态性与伊立替康毒性的相关性

目的评价伊立替康(CVT-11)联合5-氟尿嘧啶(5-Fu)和亚叶酸钙(LV)治疗晚期大肠癌的毒性与尿苷二磷酸葡糖苷酸转移酶1A(UGT1A)基因多态性的相关性。方法收集70例晚期大肠癌患者及健康志愿者的外周血,提取基因组DNA,PCR法扩增目的基因片段,直接测序法分析UGT1A基因多态性,并与毒性进行相关性分析。结果70例晚期大肠癌患者的3～4度中性粒细胞减少发生率为20.O%(14/70);2～4度迟发性腹泻发生率为22.9%(16/70),其中3-4度迟发性腹泻率仅为5.7%(4/70)。UGT1A1*28的野生基因型TA6/6患者的2-4度迟发性腹泻发生率为15.7%,低于TA6/7和TA7/7基因型的患者(P=0.027)。健康人群和大肠癌患者UGT1A基因家族中各个基因多态性的分布无差别。结论UGT1A1*28的野生基因型TA6/6在中国人中分布频率较高,这也是CPT-11为主方案治疗晚期大肠癌发生严重迟发性腹泻较少的原因。     

UGT1A1*1/*28 and *1/*6 genotypes have no effects on the efficacy and toxicity of FOLFIRI in Japanese patients with advanced colorectal cancer

Purpose

Differences in efficacy and toxicity between UDP-glucuronosyltransferase (UGT) 1A1*1/*1 and *1/*6 or *1/*28 genotypes remain unclear in Japanese patients.

Methods

Patients with advanced colorectal cancer who received irinotecan combined with 5-fluorouracil plus l-leucovorin (FOLFIRI) as first-line therapy were divided into two groups: those with UGT1A1*1/*1 genotype and those with UGT1A1*1/*6 or *1/*28 genotype. Efficacy and toxicity were compared between these groups retrospectively.

Results

Forty-two patients (24 *1/*1 and 18 *1/*6 or *1/*28) were evaluated. The response rate was 48% in *1/*1 group and 56% in *1/*6 or *1/*28 group (P?=?0.847). Median progression-free survival was 8.6?months in *1/*1 group and 8.5?months in *1/*6 or *1/*28 group (P?=?0.888). No hematologic or non-hematologic toxic effects were clearly related to UGT1A1*1/*6 or *1/*28 during the first cycle or throughout the entire course of chemotherapy.

Conclusions

There were no significant differences in the efficacy or toxicity of FOLFIRI between patients with UGT1A1*1/*1 genotype and those with UGT1A1*1/*6 or *1/*28 genotype. Our results suggest that patients with the latter genotypes can receive FOLFIRI at the same dose of irinotecan as those with the UGT1A1*1/*1 genotype receive.     

UGT1A1基因多态性与伊立替康治疗结直肠癌不良反应的关系

背景与目的：尿苷二磷酸葡萄糖醛酸转移酶1A1(uridine diphosphoglucu-ronosyltransferase 1A1,UGTlA1)是伊立替康代谢关键酶,其活性受基因多态性影响显著。本研究探讨结直肠癌患者中,UGT1A1*28和UGT1A1*6基因多态性与伊立替康治疗相关不良反应之间的关系。方法：入组2013年4月—2013年12月于复旦大学附属中山医院肿瘤内科接受治疗的消化道恶性肿瘤患者160例。抽提外周血中基因组DNA,分别采用STR方法和Sanger测序法,检测UGT1A1*28和UGT1A1*6基因型,分析UGT1A1基因多态性分布情况。对其中82例化疗方案中含伊立替康的结直肠癌患者进行随访,记录不良反应发生情况和严重程度,比较不同基因型患者之间的差异。结果：160例消化道肿瘤患者中,UTG1A1*28(启动子TATA盒区域TA重复次数)野生型TA6/6124例(77.5%);杂合子TA6/7 33例(20.5%);纯合子TA7/7 3例(2.0%)。UGT1A1*6位点(211G>A)野生型GG 105例(65.6%),杂合子GA 48例(30.0%);纯合子AA 7例(4.4%)。82例化疗方案中含伊立替康的结直肠癌患者中,*28基因型(TA6/7和TA7/7)显著增加发生3级以上中性粒细胞减少的风险(58.3% vs 0.0%,P<0.001),并增加整体不良反应发生率(76.0% vs 45.6%,P<0.001);*6基因型(GA和AA)、年龄、性别、化疗方案和伊立替康相关不良反应发生无显著相关性。结论：接受伊立替康化疗的结直肠癌患者,UGT1A1*28位点多态性显著增加中性粒细胞减少发生的风险,可预测伊立替康引起的骨髓抑制性不良反应,辅助临床选择合适的化疗方案。     

Impact of UGT1A1 genotype on the efficacy and safety of irinotecan-based chemotherapy in metastatic colorectal cancer

The phase III AXEPT study showed the noninferiority of modified capecitabine plus irinotecan (mXELIRI) with or without bevacizumab relative to fluorouracil, leucovorin, and irinotecan (FOLFIRI) with or without bevacizumab as a second-line treatment for metastatic colorectal cancer. We evaluated the associations between the UGT1A1 genotype linked to adverse events—caused by irinotecan—and the efficacy and safety of mXELIRI and FOLFIRI. The UGT1A1 genotype was prospectively determined and patients were categorized into three groups according to WT (*1/*1), single heterozygous (SH; *28/*1 or *6/*1), and double heterozygous or homozygous (DHH; *28/*28, *6/*6, or *28/*6). Overall survival (OS), progression-free survival, response rate, and safety were assessed. The UGT1A1 genotype was available in all 650 randomized patients (WT, 309 [47.5%]; SH, 291 [44.8%]; DHH, 50 [7.7%]). The median OS was 15.9, 17.7, and 10.6 months in the WT, SH, and DHH groups, respectively, with an adjusted hazard ratio (HR) of 1.53 (95% confidence interval [CI], 1.12-2.09; P = .008) for DHH vs WT or SH. The median OS in the mXELIRI and FOLFIRI arms was 18.1 vs 14.3 months (HR 0.80; 95% CI, 0.62-1.03) in the WT group, 16.3 vs 18.3 months (HR 1.04; 95% CI, 0.79-1.36) in the SH group, and 13.0 vs 9.1 months (HR 0.71; 95% CI, 0.39-1.31) in the DHH group, respectively. Modified capecitabine plus irinotecan with or without bevacizumab could be a standard second-line chemotherapy in terms of efficacy and safety regardless of the UGT1A1 genotype.     

UGT1A1基因多态性与伊立替康临床用药安全性及疗效的关系

目的：研究 UGT1A1基因多态性与伊立替康治疗结直肠癌患者的不良反应及疗效之间的关系。方法：自外周血中抽提基因组 DNA,进行 PCR 扩增,应用直接测序法分析2012年3月至2013年3月,于我院行基因检测的65例结直肠癌患者 UGT1A1*28和 UGT1A1*6基因多态性的分布情况。并对这65例应用含伊立替康方案化疗的患者出现的不良反应及化疗疗效,进行观察记录,比较不同基因型间的差异。结果：65例患者中,UGT1A1*28野生型 TA6／6有49例（75．4％）,杂合突变型 TA6／7有14例（21．5％）,纯合突变型TA7／7有2例（3．1％）。UGT1A1*6野生型 G／G 有47例（72．3％）,杂合突变型 G／A 有15例（23．1％）,纯合突变型 A ／A 有3例（4．6％）。在以上65例结直肠癌患者中,UGT1A1基因启动子区28位点,TA6／6、TA6／7和TA7／7型,发生3级以上腹泻者分别为8．2％、37．5％;发生3级以上中性粒细胞减少者分别为28．6％、62．5％。UGT1A1基因启动子区6位点,G／G、G／A 和 A ／A 型,发生3级以上腹泻者分别为12．8％、44．4％;发生3级以上中性粒细胞减少者分别为14．9％、22．2％。各组之间疗效无统计学差异。结论：患者 UGT1A1*28和UGT1A1*6多态性分布基本一致,UGT1A1*28突变型可以使应用含伊立替康化疗患者发生3级以上腹泻和中性粒细胞减少的风险增加。UGT1A1*6突变型可增加3级以上腹泻的发生风险。因此,UGT1A1基因型的检测对伊立替康相关的不良反应有一定的预测作用,可提高用药安全性,在临床用药中起到了指导作用。     

UGT1A1基因不同表型与FOLFIRI方案治疗晚期结直肠癌疗效及毒副反应的相关性

目的:回顾性分析UGT1A1基因不同表型与FOLFIRI方案治疗晚期结直肠癌疗效及毒副反应的相关性。方法:收集贵州医科大学附属肿瘤医院腹部肿瘤科2014年1月至2018年12月收治的临床分期为Ⅳ期结直肠癌或根治性手术后复发转移的晚期结直肠癌患者240例的临床病理资料,所有患者初次行FOLFIRI方案化疗前抽血,提取全血中的DNA,采用PCR技术行UGT1A1基因型检测;接受FOLFIRI化疗方案治疗直至疾病进展或者发生不可耐受的毒性反应。分别采用Binary Logistic Regression模型分析UGT1A1基因不同表型与FOLFIRI化疗疗效的相关性,分解模型及广义估计方程多应变量回归分析UGT1A1基因不同表型与FOLFIRI化疗毒副反应的相关性。结果:本组患者共发现3种UGT1A1基因表型,分别为UGT1A1*1/*1(纯合野生型TA6/6型 188/240 78.3%)、UGT1A1*28/*1(杂合突变型TA6/7型 47/240 19.6%)和UGT1A1*28/*28(纯合突变型TA7/7型 5/240 2.1%)。UGT1A1基因型中TA6/7型TA6/6型相比,FOLFIRI化疗无应答风险增加16%,但无统计学差异;本组转移器官＞2个的患者中TA6/7型和TA6/6型相比,血液学及非血液学毒副反应发生的风险均增加了9.377 3倍（P=0.007 9）,其中消化道毒副反应发生风险增加了42.806 6倍（P=0.025 9）;本组行FOLFIRI化疗≥4周期的患者中,TA6/7型比TA6/6型的患者发生血液学毒性的风险增加了22.324 6倍（P=0.003 5）。结论:TA6/6型为我省结直肠癌患者最为常见的UGT1A1基因表型,而TA7/7型罕见;晚期结直肠癌转移器官数超过2个行FOLFIRI化疗的患者中UGT1A1基因TA6/7型较TA6/6型患者血液学及非血液学毒副反应发生的风险均明显增加,其中消化道毒副反应发生的风险更胜。     

A UGT1A1*28 and *6 genotype-directed phase I dose-escalation trial of irinotecan with fixed-dose capecitabine in Korean patients with metastatic colorectal cancer

Purpose

UGT1A1 genotypes are important when considering treatment with irinotecan-containing regimens. In this study, we determined the dose, efficacy, and tolerability of irinotecan according to UGT1A1 genotypes when combined with capecitabine in patients with metastatic colorectal cancer.

Methods

Patients with histologically confirmed metastatic adenocarcinoma of the colon or rectum were enrolled into a UGT1A1 genotype-directed dose-escalation trial of irinotecan plus fixed-dose capecitabine (2,000 mg/m²/day). The starting dose of irinotecan was different for each genotype group and ranged from 200 to 280 mg/m². Pharmacokinetic concentrations of irinotecan and metabolites were determined by LC/MS/MS.

Results

Fifty patients were genotyped for UGT1A1 *28 and *6, and grouped according to the numbers of defective alleles (DA): 0, 1, and 2. Plasma concentrations of irinotecan, SN-38, and SN-38G were measured. The maximum tolerated dose of irinotecan was 350 mg/m² for the 0 and 1 DA groups, and 200 mg/m² for the 2 DA group. For the 0, 1, and 2 DA groups, mean AUC_last ratios of SN-38G to SN-38 were 7.72, 5.71, and 2.72 (P = 0.0023) and relative dose intensities at recommended dose were 85, 83, and 97 %.

Conclusion

Irinotecan dosing based on UGT1A1*28 and *6 is feasible, and higher doses of irinotecan can be safely administered in patients with 0 or 1 DA, compared to those with 2 DA.     

UGT1A1基因多态性与伊立替康为主方案治疗晚期结直肠癌的毒性和疗效的相关性分析

目的 探讨中国汉族人结直肠癌患者尿苷二磷酸葡糖苷酸转移酶1A1（UGT1A1）基因多态性分布,评价UGT1A1基因多态性与伊立替康（CPT-11）为主方案治疗晚期结直肠癌的毒性和疗效的关系。方法 以CPT-11为主的FOLFIRI方案（CPT-11 180mg／m²）和IFL方案（CPT-11 125mg／m²）治疗晚期结直肠癌,检测患者的UGT1A1*28和UGT1A1*6基因型,分析UGT1A1基因多态性及其与化疗毒性、疗效和预后的相关性。结果 共纳入192例患者,189例行UGT1A1*28和UGT1A1*6基因型检测,野生型占37.6％,1个位点变异型占43.9％,2个位点突变异型占18.5％。183例可评价毒副反应,3～4级中性粒细胞减少的发生率为26.6％（51／183）;3～4级迟发性腹泻的发生率为15.1％（29／183）。2个位点变异的患者3～4级迟发性腹泻发生率显著高于野生型患者（26.5％vs.9.0％,P=0.021）。UGT1A1*28野生型、杂合突变型、纯合突变型的2～4级迟发性腹泻的发生率分别为29.6％、37.5％和88.9％,差异具有统计学意义（P=0.02）。UGT1A1*28纯合突变者4级中性粒细胞减少的发生率为33.3％,高于UGT1A1*28野生型的9.6％,但差异无统计学意义（P=0.07）。Logistic多因素分析显示UGT1A1*28和UGT1A1*6基因型是2～4级迟发性腹泻的影响因素。CPT-11剂量高者的3～4级中性粒细胞减少（OR=5.666,95%CI：2.088～15.377,P=0.001）和2～4级迟发性腹泻（OR=4.481,95%CI：1.568～12.807,P=0.005）发生率也显著升高。158例可评价疗效,获CR 3例、PR 30例、SD 91例、PD 34例,总有效率为20.9％。2个位点变异患者的有效率为33.3％,高于野生型的15.3％,但差异无统计学意义（P=0.063）。治疗时间在6周以下者疾病进展的风险显著增加（OR=6.106,95％CI：1.680～22.197,P=0.006）。Cox多因素分析显示,ECOG评分、治疗时间及治疗方案是影响患者预后的独立因素,而UGT1A1基因多态性与预后无关。结论 UGT1A1*28和UGT1A1*6基因型2个位点变异的患者应用CPT.11为主方案化疗的不良反应发生率较高,但疗效较好,由不良反应导致的治疗时间缩短可能会影响其获得更好的疗效。     

Genetic Polymorphisms of the UDP-Glucuronosyltransferase 1A7 Gene and Irinotecan Toxicity in Japanese Cancer Patients

Irinotecan often causes unpredictably severe, occasionally fatal, toxicity involving leukopenia or diarrhea. It is converted by carboxyesterase to an active metabolite, SN–38, which is further conjugated and detoxified to SN–38–glucuronide by UDP-glucuronosyltransferase (UGT). We genotyped the UGT1A7 gene by direct sequencing analysis and polymerase chain reaction-restriction fragment length polymorphism in 118 cancer patients and 108 healthy subjects. All the patients had received irinotecan-containing chemotherapy and were evaluated to see whether the variant UGT1A7 genotype would increase the likelihood of severe toxicity of irinotecan consisting of grade 4 leukopenia and/or grade 3 or more diarrhea. Among the 26 patients with severe toxicity, the allele frequencies were 61.5% for UGT1A7*1 , 15.4% for UGT1A7*2 , and 23.1% for UGT1A7*3. On the other hand, the frequencies were 63.6% for UGT1A7*1 , 15.8% for UGT1A7*2 , and 20.7% for UGT1A7*3 among the 92 patients without severe toxicity. None of the 118 patients had UGT1A7*4. Neither univariate analysis (odds ratio, 1.13; 95% confidential interval, 0.46–2.75) nor multivariate logistic regression analysis (odds ratio, 0.74; 95% confidential interval, 0.26–2.07) found any significant association between carrying at least one of the variant alleles and the occurrence of severe toxicity. The distribution of UGT1A7 genotypes in 108 healthy subjects was not significantly different from that in the patients ( P =0.99 and 0.86 for those with and without severe toxicity, respectively), but significantly less than that in Caucasians reported previously ( P <0.001). The results suggested that determination of UGT1A7 genotypes would not be useful for predicting severe toxicity of irinotecan.     

Genetic polymorphisms of the UDP-glucuronosyltransferase 1A7 gene and irinotecan toxicity in Japanese cancer patients.

Irinotecan often causes unpredictably severe, occasionally fatal, toxicity involving leukopenia or diarrhea. It is converted by carboxyesterase to an active metabolite, SN-38, which is further conjugated and detoxified to SN-38-glucuronide by UDP-glucuronosyltransferase (UGT). We genotyped the UGT1A7 gene by direct sequencing analysis and polymerase chain reaction-restriction fragment length polymorphism in 118 cancer patients and 108 healthy subjects. All the patients had received irinotecan-containing chemotherapy and were evaluated to see whether the variant UGT1A7 genotype would increase the likelihood of severe toxicity of irinotecan consisting of grade 4 leukopenia and/or grade 3 or more diarrhea. Among the 26 patients with severe toxicity, the allele frequencies were 61.5% for UGT1A7 (*)1, 15.4% for UGT1A7 (*)2, and 23.1% for UGT1A7 (*)3. On the other hand, the frequencies were 63.6% for UGT1A7 (*)1, 15.8% for UGT1A7 (*)2, and 20.7% for UGT1A7 (*)3 among the 92 patients without severe toxicity. None of the 118 patients had UGT1A7 (*)4. Neither univariate analysis (odds ratio, 1.13; 95% confidential interval, 0.46 - 2.75) nor multivariate logistic regression analysis (odds ratio, 0.74; 95% confidential interval, 0.26 - 2.07) found any significant association between carrying at least one of the variant alleles and the occurrence of severe toxicity. The distribution of UGT1A7 genotypes in 108 healthy subjects was not significantly different from that in the patients (P = 0.99 and 0.86 for those with and without severe toxicity, respectively), but significantly less than that in Caucasians reported previously (P < 0.001). The results suggested that determination of UGT1A7 genotypes would not be useful for predicting severe toxicity of irinotecan.     

Genetic polymorphisms in human SULT1A1 and UGT1A1 genes associate with breast tumor characteristics: a case-series study

Introduction

Estrogens are important in breast cancer development. SULT1A1 and UGT1A1 catalyze estrogen metabolism and are polymorphic. The SULT1A1*2 protein exhibits low activity, and a TA repeat within the UGT1A1 promoter alters the level of expression of the protein. We hypothesized that the SULT1A1*2 allozyme has decreased capacity to sulfate estrogens, that the SULT1A1*2 allele conferred increased capacity of cells to proliferate in response to estrogens, and that individuals with the variant SULT1A1 and UGT1A1 genotypes exhibited different breast tumor characteristics.

Methods

The capacity for SULT1A1*2 to sulfate 17β-estradiol and the capacity for cells expressing SULT1A1*1 or SULT1A1*2 to proliferate in response to 17β-estradiol was evaluated. A case-series study was performed in a total of 210 women with incident breast cancer, including 177 Caucasians, 25 African-Americans and eight women of other ethnic background. The SULT1A1 and UGT1A1 genotypes were determined and a logistic regression model was used to analyze genotype–phenotype associations.

Results

We determined that the SULT1A1*1/*1 high-activity genotype was associated with tumor size ≤2 cm (odds ratio = 2.63, 95% confidence interval = 1.25–5.56, P = 0.02). Individuals with low-activity UGT1A1 genotypes (UGT1A1*28/*28 or UGT1A1*28/*34) were more likely to have an age at diagnosis ≥60 years (odds ratio = 3.70, 95% confidence interval = 1.33–10.00, P = 0.01). Individuals with both SULT1A1 and UGT1A1 high-activity genotypes had low tumor grade (odds ratio = 2.56, 95% confidence interval = 1.04–6.25, P = 0.05). Upon stratification by estrogen receptor status, significant associations were observed predominantly in estrogen receptor-negative tumors.

Conclusion

The data suggest that genetic variation in SULT1A1 and UGT1A1 may influence breast cancer characteristics and might be important for breast cancer prognosis.