Pharmacogenetics in oncology: Where we stand today?

Abstract

<p>In a given population, there is considerable variation between individuals with regard to response to as well as toxicity of different drugs. The term “Pharmacogenetics” has largely been used in relation to genes determining drug metabolism, while “Pharmacogenomics” is a broader based term that encompasses all genes in a genome that may determine drug response. In oncology, efficacy and safety of many chemotherapeutic drugs show substantial individual and/or population variability. It can be explained, to a great extent, by gene polymorphism encoding drug-metabolizing enzymes, drug transporters, and drug targets which influence the pharmacokinetics and pharmacodynamics and affect clinical outcomes. Single nucleotide polymorphisms (SNPs) are the most studied genetic variants at present due to ease, accuracy, and reduced the cost of processing as well as due to public availability of online resources for SNPs. Candidate genes for a therapeutic and adverse response can be divided into three categories: Pharmacokinetic, receptor/target, and disease-modifying. Many anticancer drugs are evaluated for their variation in response according to germline variations. This information can be easily incorporated in day-to-day practice to improve efficacy and/or safety of these drugs. In the future, advances gained from pharmacogenetics research will provide information to guide doctors in advising just enough of the right medicine to a person – The practice of “personalized medicine.”</p>