Exploring pharmacogenetics in osteosarcoma

Contains fulltext : 252878.pdf (Publisher’s version ) (Open Access)Radboud University, 06 september 2022Promotor : Brunner, H.G. Co-promotores : Coenen, M.J.H., Loo, D.M.W.M. te221 p

Analysis of drug metabolizing gene panel in osteosarcoma patients identifies association between variants inSULT1E1, CYP2B6 and CYP4F8 and methotrexate levels and toxicities

High-dose methotrexate is a cornerstone agent in the chemotherapeutic treatment of patients with osteosarcoma. However, patients often develop methotrexate-induced toxicities. We aim to identify determinants of methotrexate-induced toxicities in osteosarcoma patients by investigating the relation between drug plasma levels, methotrexate-induced toxicities, and germline variants in genes related to drug absorption, distribution, metabolism, and elimination. A cohort of 114 osteosarcoma patients was genotyped for 1,931 variants in 231 genes using the Drug Metabolism Enzymes and Transporters Plus array. Methotrexate plasma levels and laboratory measurements during and after high-dose methotrexate treatment concerning renal function, liver damage, and myelopoiesis to reflect toxicity outcomes were obtained. One hundred and thirteen patients and a subset of 545 variants in 176 genes passed quality control checks. Methotrexate plasma levels showed associations with creatinine, alanine aminotransferase, and hemoglobin. Genetic variant rs3736599 in the 5'-untranslated region ofSULT1E1 was associated with lower 48 hour methotrexate plasma levels [coef -0.313 (95% CI -0.459 - -0.167); p = 2.60 x 10(-5)]. Association with methotrexate-induced decreased thrombocyte counts was found for two intronic variants in CYP2B6{rs4803418 [coef -0.187 (95% CI -0.275 - -0.099); p = 3.04 x 10(-5)] and rs4803419 [coef -0.186 (95% CI -0.278 - -0.093); p = 8.80 x 10(-5)]}. An association with increased thrombocyte counts was identified for the intronic variant rs4808326 in CYP4F8 [coef 0.193 (95% CI 0.099 - 0.287); p = 6.02 x 10(-5)]. Moreover, a secondary analysis with a binary approach using CTCAE toxicity criteria resulted in a nominal significant associations (p < 0.05) for two out of three variants (rs4803418 and rs4808326). This is the first study to identify genetic variants inSULT1E1, CYP2B6, andCYP4F8to be associated with methotrexate pharmacokinetics and toxicities. Validation of these variants in an independent cohort and further functional investigation of variants in the identified genes is needed to determine if and how they affect methotrexate plasma levels and the development of methotrexate-induced toxicities

Genome-wide analyses of platinum-induced ototoxicity in childhood cancer patients: Results of GO-CAT and United Kingdom MAGIC consortia

Hearing loss (ototoxicity) is a major adverse effect of cisplatin and carboplatin chemotherapy. The aim of this study is to identify novel genetic variants that play a role in platinum-induced ototoxicity. Therefore, a genome-wide association study was performed in the Genetics of Childhood Cancer Treatment (GO-CAT) cohort (n = 261) and the United Kingdom Molecular Genetics of Adverse Drug Reactions in Children Study (United Kingdom MAGIC) cohort (n = 248). Results of both cohorts were combined in a meta-analysis. In primary analysis, patients with SIOP Boston Ototoxicity Scale grade & GE;1 were considered cases, and patients with grade 0 were controls. Variants with a p-value < 10(-5) were replicated in previously published data by the PanCareLIFE cohort (n = 390). No genome-wide significant associations were found, but variants in TSPAN5, RBBP4P5, AC010090.1 and RNU6-38P were suggestively associated with platinum-induced ototoxicity. The lowest p-value was found for rs7671702 in TSPAN5 (odds ratio 2.0 (95% confidence interval 1.5-2.7), p-value 5.0 x 10(-7)). None of the associations were significant in the replication cohort, although the effect directions were consistent among all cohorts. Validation and functional understanding of these genetic variants could lead to more insights in the development of platinum-induced ototoxicity

SLC7A8 coding for LAT2 is associated with early disease progression in osteosarcoma and transports doxorubicin

Background: Despite (neo)adjuvant chemotherapy with cisplatin, doxorubicin and methotrexate, some patients with primary osteosarcoma progress during first-line systemic treatment and have a poor prognosis. In this study, we investigated whether patients with early disease progression (EDP), are characterized by a distinctive pharmacogenetic profile. Methods and Findings: Germline DNA from 287 Dutch high-grade osteosarcoma patients was genotyped using the DMET Plus array (containing 1,936 genetic markers in 231 drug metabolism and transporter genes). Associations between genetic variants and EPD were assessed using logistic regression models. The datafile (Hurkmans_SumStat_LogReg_DMET_EarlyProgressiveDisaese_CovarMetasSexAge_GRCh37.txt) contains the results of this anaylsis. Conclusions: This study identified a novel locus in SLC7A8 to be associated with EPD in osteosarcoma

SLC7A8 coding for LAT2 is associated with early disease progression in osteosarcoma and transports doxorubicin

Background: Despite (neo) adjuvant chemotherapy with cisplatin, doxorubicin and methotrexate, some patients with primary osteosarcoma progress during first-line systemic treatment and have a poor prognosis. In this study, we investigated whether patients with early disease progression (EDP), are characterized by a distinctive pharmacogenetic profile. Methods and Findings: Germline DNA from 287 Dutch high-grade osteosarcoma patients was genotyped using the DMET Plus array (containing 1,936 genetic markers in 231 drug metabolism and transporter genes). Associations between genetic variants and EDP were assessed using logistic regression models and associated variants (p < 0.05) were validated in independent cohorts of 146 (Spain and United Kingdom) and 28 patients (Australia). In the association analyses, EDP was significantly associated with an SLC7A8 locus and was independently validated (meta-analysis validation cohorts: OR 0.19 [0.06-0.55], p = 0.002). The functional relevance of the top hits was explored by immunohistochemistry staining and an in vitro transport models. SLC7A8 encodes for the L-type amino acid transporter 2 (LAT2). Transport assays in HEK293 cells overexpressing LAT2 showed that doxorubicin, but not cisplatin and methotrexate, is a substrate for LAT2 (p < 0.0001). Finally, SLC7A8 mRNA expression analysis and LAT2 immunohistochemistry of osteosarcoma tissue showed that the lack of LAT2 expression is a prognostic factor of poor prognosis and reduced overall survival in patients without metastases (p = 0.0099 and p = 0.14, resp.). Conclusion: This study identified a novel locus in SLC7A8 to be associated with EDP in osteosarcoma. Functional studies indicate LAT2-mediates uptake of doxorubicin, which could give new opportunities to personalize treatment of osteosarcoma patients.Personalised Therapeutic

SLC7A8 coding for LAT2 is associated with early disease progression in osteosarcoma and transports doxorubicin

Background: Despite (neo)adjuvant chemotherapy with cisplatin, doxorubicin and methotrexate, some patients with primary osteosarcoma progress during first-line systemic treatment and have a poor prognosis. In this study, we investigated whether patients with early disease progression (EDP), are characterized by a distinctive pharmacogenetic profile. Methods and Findings: Germline DNA from 287 Dutch high-grade osteosarcoma patients was genotyped using the DMET Plus array (containing 1,936 genetic markers in 231 drug metabolism and transporter genes). Associations between genetic variants and EPD were assessed using logistic regression models. The datafile (Hurkmans_SumStat_LogReg_DMET_EarlyProgressiveDisaese_CovarMetasSexAge_GRCh37.txt) contains the results of this anaylsis. Conclusions: This study identified a novel locus in SLC7A8 to be associated with EPD in osteosarcoma