2221 KB54 KB199220251998Osmak, Majaštevilka:1letnik:32str. 19-33ISSN:1318-2099COBISSID:7823065URN:URN:NBN:SI:doc-CKOCW4R2enCroatian Medical Association - Croatian Society of RadiologySlovenian Medical Society - Section of RadiologyRadiology and oncology (Ljubljana)Antineoplastic agentscitostatikiDna repairDna topoisomeraseDrug resistanceDrug resistance, neoplasmGene amplificationGlutathioneGlutathione peroxidaseGlutathione transferasesMetallothioneinmolekularna biologijaodpornostrak (medicina)tumorske celicezdravljenjeMolecular alterations induced in drug-resistant cells|The major obstacle to the ultimate success in cancer therapy is the ability oftumor cells to develop resistance to anticancer drugs. Several molecular mechanisms have been suggested to be involved in drugresistance: a) decrease in the intracellular drug accumulation (increased activity of membrane transporters such as P-glycoprotein or multidrug-resistance-associated protein), b) changes in intracellular detoxification system (increased concentrations of glutathione or metallothioneins, or increased activity of related enzymed), c) alteration in nuclear enzymes (enhanced DNA repair and/orbetter tolerance of DNA damage, decreased acitivty of topoisomerases), d) altered expression of oncogenes (inducing increased level of protective molecules in cells or the inhibition of apoptosis). Drug resistance is a multifactorial phenomenon. The complexity of molecular alterations in drug-resistant cells is and will stay the main problem for the successful treatment of cancerTEXTznanstveno časopisjejournalsSlovenian National E-content AggregatorNational and University Library of SloveniaOnkološki inštitut Ljubljana