Farmakogenetika 6-merkaptopurina i metotreksata u dečjoj akutnoj limfoblastnoj leukemiji

Abstract

Farmakogenomika proučava odnos između genetičkog sklopa individue i njegovog odgovora na lekove i jedan je od stubova personalizovane medicine. Dosadašnji princip lečenja da se standardna doza leka daje svim pacijentima sa istom dijagnozom po unapred utvrđenom protokolu se napušta. Za veliki broj pacijenta ta doza leka često nije efikasna i/ili sigurna za upotrebu. Cilj farmakogenomičkih studija je da identifikuju farmakogenomičke markere, varijacije u genomu koje mogu pouzdano da predvide odgovor na terapiju, što je osnov za individualizaciju terapije. Model sistemi bolesti za analizu farmakogenomičkih markera korišćeni u ovom radu su dečja akutna limfoblastna leukemija (ALL) i reumatoidni artritis (RA). Lečenje ovih bolesti uključuje imunosupresivne i citotoksične lekove 6-merkaptopurin (6-MP), metotreksat (MTX), antibiotik baktrim, antimikotik nistatin, kao i anti-TNF lekove. Genetičke varijacije koje modulišu metaboličke puteve povezane sa ovim lekovima su kandidati za farmakogenomičke markere. Cilj ove studije je da ispita učestalosti genetičkih varijanti u genima TPMT, ITPA, ABCB1, ABCC4, TYMS, MTHFR, SLC19A1, DHFR, TNF i IL-6, kao i da oceni farmakogenomički potencijal ovih varijanti u srpskoj populaciji. Biće ispitana i uloga ovih farmakogenomičkih markera kao faktora rizika za razvoj dečje ALL. Ispitaće se i uticaj terapije održavanja, gde okosnicu terapije čine lekovi 6-MP i MTX, kao i pola i uzrasta dece sa ALL na ekspresiju gena TPMT. Biće funkcionalno okarakterisane varijante u genu TPMT, potencijalni modulatori ekspresije gena TPMT, sa posebnom pažnjom na ulogu VNTR regiona u promotoru gena TPMT. U studiju je bilo uključeno 174 pedijatrijskih ALL pacijenata, 73 RA pacijenata i 104 kontrolnih zdravih ispitanika. Genetičke varijacije u svim gorepomenutim genima su određene metodama baziranim na PCR-u...

Pharmacogenomics is focused on exploring the relation between the genomic signature of an individual and their drug response. It is the basis for implementation of personalized medicine. The old-fashioned therapeutic paradigm of »one protocol dose fits all patients with the same diagnosis« is getting abandoned. The standard drug dose is often not efficient and/or safe for many of patients. Pharmacogenomic studies identify pharmacogenomic markers, genomic variations that could reliably predict the drug response, which is the basis for therapy individualization. In order to analyze pharmacogenomic markers, childhood acute lymphoblastic leukemia (ALL) and rheumatoid arthritis (RA) are used as disease model systems. ALL and RA therapy protocols include cytotoxic and immunosuppressive drugs 6-mercaptopurine (6-MP) and methotrexate (MTX), antibiotic bactrim and antimycotic nystatin, as well as anti-TNF drugs. Genetic variations that modulate metabolic pathways related to these drugs are candidate pharmacogenomic markers. The aim of this study is to analyze frequencies of genetic variants in TPMT, ITPA, ABCB1, ABCC4, TYMS, MTHFR, SLC19A1, DHFR, TNF and IL-6 genes in Serbian population and to evaluate the pharmacogenomic potential of these variants. Also, the role of these pharmacogenomic markers as risk factors for development of childhood ALL will be assessed. Influence of the maintenance therapy, which includes 6-MP and MTX as most important drugs, as well as the age and gender of patients will be analyzed in regard to TPMT gene expression. Functional assays will be carried out in order to identify potential modifiers of TPMT expression with a special focus on VNTR region in promoter of TPMT gene. In this study, 174 pediatric ALL patients, 73 RA patients and 104 healthy subjects were enrolled. Genetic variants in above-mentioned genes were detected using PCR-based methodology...