ATYPICAL RESPONDERS LANDSCAPE REVIEW ∙ OCTOBER, 2017 40 Overexpression: levels, often of a protein or mRNA, that are higher than normal Partial response (PR): in cancer, a reduction in a tumor following a treatment, but not a complete disappearance Pharmacogenomics: the study of how genes affect a person’s response to drugs Pharmacokinetics: the body’s processing of drugs Phenotype: the characteristics of a protein, cell, organ, or organism as determined by its genes Polymorphisms: different forms of a gene, which are called “variant alleles”. Precision medicine /personalized medicine: using an individual’s particular genes and other characteristics to select treatments for a disease Pro-drug: A pro-drug is an inactive drug that you take that the body “activates”, usually by the liver. Tamoxifen is one example of a pro-drug that the liver converts to its active form. Promoter methylation: the promoter is a section of a gene that regulates expression of the gene (i.e., if the gene is switched “on” or “off”). Methylation is addition of a chemical group called a methyl group. Addition or removal of a methyl group from a promoter is a common way for cells to temporarily turn genes on or off. Prospective: when used to describe a trial or data, prospective means that the information will be collected in the future according to a specified plan. Quality of life (QOL): a person’s well-being and satisfaction with life that includes the person’s ability or desire to participate in social, physical, employment, education, religious, etc. activities Retrospective: when used to describe a trial or data, retrospective means that the information already exists, such as in electronic medical records or banked tumor samples, and will be collected and analyzed as is Surveillance, Epidemiology, and End Results (SEER): A program of the National Cancer Institute that acts as a repository for cancer statistics concerning incidence and survival in the US Single nucleotide polymorphism (SNP): a small, single change in the DNA sequence Somatic mutations: changes in DNA that originate in the tumor and are thus not inheritable (not passed down to offspring because they are not present in eggs and sperm). Such changes may impact cancer progression and acquired resistance to therapy. Stroma: connective tissue