Prospective study of the UGT1A1*27 gene polymorphism during irinotecan therapy in patients with lung cancer: Results of Lung Oncology Group in Kyusyu (LOGIK1004B)

A comprehensive Thai pharmacogenomics database (TPGxD-1): Phenotype prediction and variants identification in 942 whole-genome sequencing data

Computational methods analyze genomic data to identify genetic variants linked to drug responses, thereby guiding personalized medicine. This study analyzed 942 whole-genome sequences from the Electricity Generating Authority of Thailand (EGAT) cohort to establish a population-specific pharmacogenomic database (TPGxD-1) in the Thai population. Sentieon (version 201808.08) implemented the GATK best workflow practice for variant calling. We then annotated variant call format (VCF) files using Golden Helix VarSeq 2.5.0 and employed Stargazer v2.0.2 for star allele analysis. The analysis of 63 very important pharmacogenes (VIPGx) reveals 85,566 variants, including 13,532 novel discoveries. Notably, we identified 464 known PGx variants and 275 clinically relevant novel variants. The phenotypic prediction of 15 VIPGx demonstrated a varied metabolic profile for the Thai population. Genes like CYP2C9 (9%), CYP3A5 (45.2%), CYP2B6 (9.4%), NUDT15 (15%), CYP2D6 (47%) and CYP2C19 (43%) showed a high number of intermediate metabolizers; CYP3A5 (41%), and CYP2C19 (9.9%) showed more poor metabolizers. CYP1A2 (52.7%) and CYP2B6 (7.6%) were found to have a higher number of ultra-metabolizers. The functional prediction of the remaining 10 VIPGx genes reveals a high frequency of decreased functional alleles in SULT1A1 (12%), NAT2 (84%), and G6PD (12%). SLCO1B1 reports 20% poor functional alleles, while PTGIS (42%), SLCO1B1 (4%), and TPMT (5.96%) showed increased functional alleles. This study discovered new variants and alleles in the 63 VIPGx genes among the Thai population, offering insights into advancing clinical pharmacogenomics (PGx). However, further validation is needed using other computational and genotyping methods.

Irinotecan monotherapy as third- or further-line treatment for patients with small cell lung cancer

BACKGROUND

Small cell lung cancer (SCLC) is a very aggressive cancer and recurrence is inevitable. Treatment of recurrent disease is important for improving the prognosis of patients with SCLC.

METHODS

We conducted a retrospective observational study to investigate the efficacy and safety of irinotecan monotherapy as third- or further-line treatment in patients with SCLC.

RESULTS

Data of 15 patients who had received irinotecan monotherapy as third- or further-line treatment between 2004 and 2019 were analyzed. The median progression-free survival duration (95% confidence interval) from the initiation of treatment with irinotecan was 2.7 (1.4-3.8) months, and the median overall survival duration (95% confidence interval) from the initiation of irinotecan treatment was 10.0 (3.9-12.9) months. Partial response, stable disease or non-complete response/non-progressive disease, and progressive disease were observed in 1, 6, and 8 patients, respectively. Adverse events ⩾ grade 3 in severity were observed in 2/2 (100%) patients who were homozygous for UGT1A1 mutation, 2/3 (66.7%) patients who were heterozygous for UGT1A1 mutation, 4/6 (66.7%) patients who had wild-type UGT1A1, and 2/4 (50.0%) patients in whom the UGT1A1 mutation status was unknown.

CONCLUSION

Our results suggest that irinotecan monotherapy can be a useful alternative treatment option in the third-line setting for patients with SCLC.

UGT1A1 regulatory variant with potential effect on efficacy of HIV and cancer drugs commonly prescribed in South Africa

Aim: Despite the high disease burden of human immunodeficiency virus (HIV) infection and colorectal cancer (CRC) in South Africa (SA), treatment-relevant pharmacogenetic variants are understudied. Materials & methods: Using publicly available genotype and gene expression data, a bioinformatic pipeline was developed to identify liver expression quantitative trait loci (eQTLs). Results: A novel cis-eQTL, rs28967009, was identified for UGT1A1, which is predicted to upregulate UGT1A1 expression thereby potentially affecting the metabolism of dolutegravir and irinotecan, which are extensively prescribed in SA for HIV and colorectal cancer treatment, respectively. Conclusion: As increased UGT1A1 expression could affect the clinical outcome of dolutegravir and irinotecan treatment by increasing drug clearance, patients with the rs28967009A variant may require increased drug doses to reach therapeutic levels or should be prescribed alternative drugs.

Molecular biomarkers and precision medicine in colorectal cancer: a systematic review of health economic analyses

An increased understanding of the biology of colorectal cancer (CRC) has fuelled identification of biomarkers with potential to drive a stratified precision medicine care approach in this common malignancy. We conducted a systematic review of health economic assessments of molecular biomarkers (MBMs) and their employment in patient stratification in CRC. Our analysis revealed scenarios where health economic analyses have been applied to evaluate the cost effectiveness of MBM-guided clinical interventions: (i) evaluation of Dihydropyrimidine dehydrogenase gene (DPYD) status to identify patients susceptible to 5-Fluouracil toxicity; (ii) determination of Uridine 5'-diphospho- glucuronosyltransferase family 1 member A1 gene (UGT1A1) polymorphism status to help guide irinotecan treatment; (iii) assessment of RAS/RAF mutational status to stratify patients for chemotherapy or Epidermal Growth Factor Receptor (EGFR) therapy and (iv) multigene expression analysis (Oncotype Dx) to identify and spare non-responders the debilitating effects of particular chemotherapy interventions. Our findings indicate that Oncotype Dx is cost-effective in high income settings within specific price points, by limiting treatment toxicity in CRC patients. DPYD status testing may also be cost effective in certain settings to avoid specific 5-FU toxicities post treatment. In contrast, current research does not support UGT1A1 polymorphism status as a cost-effective guide to irinotecan dosing, while the health economic evidence to support testing of KRAS/NRAS mutational status and chemo/EGFR therapy choice was inconclusive, despite its widespread adoption in CRC treatment management. However, we also show that there is a paucity of high-quality cost-effectiveness studies to support clinical application of precision medicine approaches in CRC.

Association of nephrotoxicity during platinum-etoposide doublet therapy with UGT1A1 polymorphisms in small cell lung cancer patients

OBJECTIVES

Etoposide is a key agent in the treatment of small cell lung cancer (SCLC). Uridine diphosphate (UDP)-glucuronosyltransferase 1A1 (UGT1A1) is thought to be largely responsible for the glucuronidation of etoposide as well as that of irinotecan, suggesting that polymorphisms of UGT1A1 might be predictive of etoposide toxicity. We therefore examined the relation between UGT1A1 polymorphisms and toxicity profile during platinum-etoposide doublet therapy in SCLC patients.

MATERIALS AND METHODS

SCLC patients who underwent platinum-etoposide doublet therapy and molecular testing for UGT1A1 genotype were reviewed for the occurrence of adverse events during treatment.

RESULTS

A total of 41 SCLC patients received platinum-etoposide doublet therapy and were genotyped for UGT1A1*6 and UGT1A1*28 alleles. These alleles were detected in 15 (36.6%) patients, with the genotypes of *6/-, *6/*6, *28/-, *28/*28, or *6/*28 being observed in 9 (22.0%), 2 (4.9%), 2 (4.9%), 1 (2.4%), and 1 (2.4%) patients, respectively. The presence of these alleles was significantly associated with an increase in serum creatinine concentration of grade ≥2 (incidence of 66.7% for patients with the alleles versus 11.5% for those without, P <  0.001). Multivariate analysis also showed that these UGT1A1 alleles were significantly associated with therapy-induced nephrotoxicity (odds ratio of 19.30, 95% confidence interval of 2.50-149.00, P <  0.005). Although the differences did not achieve statistical significance, the incidence of other severe toxicities including febrile neutropenia was also slightly higher in patients with the UGT1A1*6 or UGT1A1*28 alleles than in those without them.

CONCLUSION

Our results reveal an association between UGT1A1 polymorphisms and toxicity of platinum-etoposide doublet therapy in SCLC patients, suggesting that close monitoring for toxicity, especially nephrotoxicity, is warranted for patients with such variant alleles receiving this treatment.

[Detection of UGT1A1*28 Polymorphism Using Fragment Analysis]

背景与目的

尿苷二磷酸葡萄糖醛酸转移酶（uridine diphosphate glucuronosyl transferase 1A1, UGT1A1）是伊立替康代谢最主要的同工酶，UGT1A1基因的多态性影响UGT1A1的活性，本研究建立片段分析法检测UGT1A1^*28 TATA盒的多态性。

方法

调取2014年4月-2015年5月在广东省人民医院的住院肺癌患者库存血液标本286例，建立片段分析法检测UGT1A1^*28 TATA多态性，与Sanger测序方法比较其精确度和准确度。

结果

286例肿瘤血液中，UGT1A1^*28 TATA盒TA6/6型有236例（82.5%），TA6/7型有48例（16.8%），TA7/7型2例（0.7%）。片段分析法与Sanger测序法比较，精确度与准确度达100%。

结论

片段分析法适用于临床检测UGT1A1^*28多态性，成本低且方便快捷。

Relationship between UGT1A1*27 and UGT1A1*7 polymorphisms and irinotecan-related toxicities in patients with lung cancer

Background

The objective of this study was to evaluate the effects of gene polymorphisms, including UGT1A1*7, *27, and *29, on the safety of irinotecan therapy.

Methods

The eligibility criteria were: lung cancer patients scheduled to undergo irinotecan therapy, aged ≥ 20 years, with a performance status of 0–2. Thirty‐one patients were enrolled and their blood was collected and used to examine the frequency of UGT1A1*6, *7, *27, *28, and *29 polymorphisms and the concentrations of irinotecan, SN‐38, and SN‐38G after irinotecan therapy.

Results

The patients’ characteristics were as follows: male/female 25/6, median age 71 years (range 55–84), stage IIB/IIIA/IIIB/IV 2/6/11/12, and adenocarcinoma/squamous cell carcinoma/small cell carcinoma/other 14/10/3/4, respectively. The −/−, *6/−, *7/−, *27/−, *28/−, and *29/− UGT1A1 gene polymorphisms were observed in 10 (32%), 10 (32%), 2 (6%), 2 (6%), 7 (23%), and 0 (0%) cases, respectively. The UGT1A1*27 polymorphism occurred separately from the UGT1A1*28 polymorphism. The lowest leukocyte counts of the patients with the UGT1A1*27 and UGT1A1*6 gene polymorphisms were lower than those observed in the wild‐type patients. SN‐38 tended to remain in the blood for a prolonged period after the infusion of irinotecan in patients with UGT1A1*27 or UGT1A1*28 polymorphisms. No severe myelotoxicity was seen in the patients with UGT1A1*7.

Conclusion

UGT1A1*27 can occur separately from UGT1A1*28 and is related to leukopenia during irinotecan treatment. UGT1A1*7 is less relevant to irinotecan‐induced toxicities, and UGT1A1*29 seems to have little clinical impact.

UGT1A1 polymorphisms with irinotecan-induced toxicities and treatment outcome in Asians with Lung Cancer: a meta-analysis

Previous studies of irinotecan pharmacogenetics have shown that the UGT1A1*28 polymorphism has an effect on irinotecan (IRI)-induced toxicities in Caucasians. Yet compared with the UGT1A1*6 mutation, the UGT1A1*28 occurs at a much lower frequency in the Asians. Whether UGT1A1*6 and UGT1A1*28 are associated with IRI-induced neutropenia, diarrhea and IRI-based chemotherapy tumor response (TR) in Asians with lung cancer remains controversial. In this meta-analysis, we found a higher risk of neutropenia and diarrhea with IRI-based chemotherapy in Asians with lung cancer carrying the UGT1A1*6 polymorphism. However, UGT1A1*28 showed a weak correlation with diarrhea, but no significant correlation with neutropenia. Neither UGT1A1*6 nor UGT1A1*28 is associated with IRI-based chemotherapy TR. These data suggest that the UGT1A1*28 polymorphism may not be a suitable biomarker to predict IRI-induced toxicities and chemotherapy TR in Asians, while UGT1A*6 polymorphism is associated with a higher risk of IRI-induced neutropenia and diarrhea, but not IRI-based chemotherapy TR.

Phase I study of irinotecan for previously treated lung cancer patients with the UGT1A1*28 or *6 polymorphism: Results of the Lung Oncology Group in Kyushu (LOGIK1004A)

Background

Various polymorphisms have been detected in the UDP‐glucuronosyltransferase 1A (UGT1A) gene, and UGT1A1*28 and UGT1A1*6 have important effects on the pharmacokinetics of irinotecan and the risk of severe toxicities during irinotecan therapy. This study was conducted to determine the maximum tolerated dose (MTD) of irinotecan chemotherapy according to the UGT1A1 genotype in previously treated lung cancer patients with the UGT1A1*28 or UGT1A1*6 polymorphism.

Methods

The eligibility criteria were as follows: lung cancer patients that had previously been treated with anticancer agents other than irinotecan, possessed the UGT1A1*28 or UGT1A1*6 polymorphism (group A included *28/*28, *6/*6, and *28/*6, and group B included *28/− and *6/−), were aged ≤75 years old, had a performance score of 0–1, and exhibited adequate bone marrow function. The patients were scheduled to receive irinotecan on days 1, 8, 15, 22, 29, and 36.

Results

Four patients were enrolled in this trial. Two patients were determined to be ineligible. The remaining two patients, who belonged to group B, received an initial irinotecan dose of 60 mg/m², but did not complete the planned treatment because of diarrhea and leukopenia. Thus, in group B patients, 60 mg/m² was considered to be the MTD of irinotecan. The study was terminated in group A because of poor case recruitment.

Conclusions

The MTD of irinotecan for previously treated lung cancer patients that are heterozygous for the UGT1A1*28 or UGT1A1*6 gene polymorphism is 60 mg/m².