| Glossary
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
A
Analytes
A substance that has been measured and/or analyzed in some fashion.
Apoptosis
Cell-induced suicide; cells use this mechanism under a number of different conditions, including when errors have been made in the DNA that have not been corrected.
B
Benign tumor
A tumor that has not gained the ability to invade into other host tissues and/or organs; usually non-life threatening.
Biospecimen
Materials taken from the human body, such as blood, tissue, plasma and urine, that can be used for cancer diagnosis and analysis.
Biorepository
A “Library” where biospecimens are stored and made available for scientists to study for clinical or research purposes; also known as biobank.
C
Cancer
A term for diseases in which abnormal cells divide without control and can invade nearby tissues. Cancer cells can also spread to other parts of the body through the blood and lymph systems. There are several main types of cancer. Carcinoma is a cancer that begins in the skin or in tissues that line or cover internal organs. Sarcoma is a cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue. Leukemia is a cancer that starts in blood-forming tissue such as the bone marrow, and causes large numbers of abnormal blood cells to be produced and enter the blood. Lymphoma and multiple myeloma are cancers that begin in the cells of the immune system. Central nervous system cancers are cancers that begin in the tissues of the brain and spinal cord. Also called malignancy.
Carcinogen
Any substance that causes cancer.
Cell
The individual unit that makes up the tissues of the body. All living things are made up of one or more cells.
Chemotherapy
A form of cancer therapy that uses drugs to kill cancer cells.
Chromosome
A structure within a cell that carries genes. A chromosome consists of a continuous molecule of DNA and the proteins wrapped around it.
Cryosurgery
A form of cancer therapy that uses extreme cold to kill and remove cancer cells.
D
DNA
Deoxyribonucleic acid. The molecules inside cells that carry genetic information and pass it from one generation to the next. Also called deoxyribonucleic acid.
G
Gene
The functional and physical unit of heredity passed from parent to offspring. Genes are pieces of DNA, and most genes contain the information for making a specific protein.
Gene Expression
The process by which proteins are made from the instructions encoded in DNA.
Genome
All of the DNA contained in the cell of an organism, which includes both the chromosomes within the nucleus and the DNA in mitochondria; the complete genetic material of an organism.
Genomic characterization
A profile of the entire genome or a segment of DNA with regard to changes in the genome and/or DNA. Characterization can include point mutation analysis, gene expression profiling and determination of chromosome gains and/or losses.
Genomics
The study of the complete genetic material, including genes and their functions, of an organism.
Genotype
The genetic identity of a specific location of DNA, a particular trait, a set of traits or an entire organism that does not necessarily show as outward characteristics.
Germline mutations
Mistakes in DNA that are inherited from parents to the child.
Glioblastoma multiforme
A fast-growing type of central nervous system tumor that forms from glial (supportive) tissue of the brain and spinal cord and has cells that look very different from normal cells. Glioblastoma multiforme usually occurs in adults and affects the brain more often than the spinal cord. Also called GBM, glioblastoma, and grade IV astrocytoma.
H
Health Insurance Portability and Accountability Act (HIPAA) of 1996
Act instituted to “establish national standards for electronic health care…” and to ensure “the security and privacy of health data”. For more information on HIPAA, see: http://www.cms.hhs.gov/HIPAAGenInfo/
I
Informed consent
A process in which a person is given important facts about a medical procedure or treatment, a clinical trial, or genetic testing before deciding whether or not to participate. It also includes informing the patient when there is new information that may affect his or her decision to continue. Informed consent includes information about the possible risks, benefits, and limits of the procedure, treatment, trial, or genetic testing.
M
Malignant
Cancerous. Malignant tumors can invade and destroy nearby tissue and spread to other parts of the body.
Metastasis
The spread of cancer from one part of the body to another. A tumor formed by cells that have spread is called a “metastatic tumor” or a “metastasis.” The metastatic tumor contains cells that are like those in the original (primary) tumor.
Mutations
Any change in the DNA of a cell. Mutations may be caused by mistakes during cell division, or they may be caused by exposure to DNA-damaging agents in the environment. Mutations can be harmful, beneficial, or have no effect. If they occur in cells that make eggs or sperm, they can be inherited; if mutations occur in other types of cells, they are not inherited. Certain mutations may lead to cancer or other diseases.
O
Organ
A part of the body that performs a specific function. For example, the heart is an organ.
Ovarian Cancer
Cancer that forms in tissues of the ovary (one of a pair of female reproductive glands in which the ova, or eggs, are formed). Most ovarian cancers are either ovarian epithelial carcinomas (cancer that begins in the cells on the surface of the ovary) or malignant germ cell tumors (cancer that begins in egg cells).
P
Polymorphism
A common variation or mutation in DNA.
Prospective collection
In TCGA, refers to the process of developing criteria for tissues for this project and then contacting clinicians who can identify patients with tumor/normal tissue samples for collection that meet these criteria over time.
R
Radiation therapy
The use of high-energy radiation from x-rays, gamma rays, neutrons, protons, and other sources to kill cancer cells and shrink tumors. Radiation may come from a machine outside the body (external-beam radiation therapy), or it may come from radioactive material placed in the body near cancer cells (internal radiation therapy).
Request for Applications (RFA)
Initiative sponsored by one or more NIH institutes or centers that stimulates targeted research by requesting grant proposals in a well-defined scientific area. RFAs have a single receipt date and identify funds set aside and the number of awards likely to be made. Institutes publish RFAs in the NIH Guide and in Grants.gov as funding opportunity announcements.
Retrospective collection
In TCGA, refers to the process of developing criteria for tissues for this project and then finding existing repositories of tissue samples for collection that meet those criteria.
S
DNA Sequencing
Determining the exact order of the base pairs in a segment of DNA
Somatic mutations
An alteration in DNA that occurs after conception. Somatic mutations can occur in any of the cells of the body except the germ cells (sperm and egg) and therefore are not passed on to children. These alterations can (but do not always) cause cancer or other diseases.
Squamous cell
Flat cell that looks like a fish scale under a microscope. These cells cover inside and outside surfaces of the body. They are found in the tissues that form the surface of the skin, the lining of the hollow organs of the body (such as the bladder, kidney, and uterus), and the passages of the respiratory and digestive tracts.
T
Targeted therapy
A type of treatment that uses drugs or other substances, to identify and attack specific cancer cells without harming normal cells.
Tissue
A group or layer of cells that work together to perform a specific function.
Tissue source site (TSS)
Any location that serves the function of supplying TCGA with normal and/or tumor samples, no matter the source (commercial, academic, etc.).
Transcription
In biology, the process by which a cell makes an RNA copy of a sequence of DNA that is a gene.
Transcriptome
A transcriptome is the collection of all the gene transcripts present in a cell.
Tumor
An abnormal mass of tissue that results when cells divide more than they should or do not die when they should. Tumors may be benign (not cancerous), or malignant (cancerous).
| 
