GENE - The biologic unit of heredity. A gene is composed of DNA. Genes make up chromosomes.
GENE THERAPY - A treatment in which genetic information is either introduced, amplified, or deleted from cells.
GLEASON SCORE - A numerical value given to prostate cancers that quantitates tumor grade. Scores are assigned to the most common pattern of cancer as well as the second most common. Scores for each pattern range from 1 to 5. A score of 1 denotes a cancer that closely resembles benign or normal tissue. A score of 5 is assigned to cancers that appear aggressive and differ significantly from benign tissue.
GLEASON SYSTEM (GRADE AND SCORE) - This system is used to determine how aggressive a prostate cancer is. Samples of prostate cancer cells are examined under a microscope and graded by number according to how much they differ from normal prostate cells. These grades are then added for an overall score.
GROWTH FACTORS - Protein signaling molecules, similar in structure and activity to the protein hormones, which usually act in a paracrine or autocrine fashion to regulate cell growth and differentiation.