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Assay Development - Assay Development refers to the process of building a test (or assay) that measures the levels of a specific biomarker. This process typically involves the following 3 main stages: i) biomarker (protein) production ii) antibody development and iii) assay optimization.

Biomarker - Biomarker is a molecular, biological, or physical characteristic that is objectively measured and evaluated as an indicator of normal biologic processes, disease state, or response to therapeutic intervention. Biomarkers can be used to identify risk for a disease, to make a diagnosis, to assess disease severity, and to guide treatment. Examples of biomarkers include CA 125 (ovarian cancer), CA 15-3 (breast cancer), CEA (ovarian, lung, breast, pancreas, and gastrointestinal tract cancers), and PSA (prostate cancer). Biomarkers are also called tumor markers and for early cancer detection, no single biomarker test is likely to be a 'silver bullet' but rather a definitive diagnosis will be based on measurements of several biomarkers at once.

The ideal blood biomarker for early cancer detection is a protein or other biomolecule whose abundance in the blood (or other fluid) is consistently higher (or lower) in people with very early stage cancer relative to those without cancer. Such a biomarker would typically be a protein that is secreted by cancerous cells into the blood, but not by other cells in the body.

The ideal molecular imaging biomarker for early cancer detection is a protein (or other biomolecule) that is highly abundant on the surface of tumor cells (or associated cells) but absent from the surface of all other cells in the body. A specific labeled probe binding to this biomarker would allow the doctor to visualize the tumor directly inside the person being screened.

Biomarker Discovery - Biomarker discovery is the process of predicting which biological molecules might serve as indicators of a specific type of cancer because they are only found at certain levels within individuals with that disease. Canary Foundation employs cutting edge genomic, epigenomic and proteomic tools for biomarker discovery.

Biomarker Performance - Biomarker performance is typically measured in terms of sensitivity and specificity. The ideal cancer biomarker is 100% sensitive and 100% specific: it is always found in the blood (or other fluid) of patients with very early stage cancer, but never found in the blood of anyone that does not have the disease ("control subjects"). It may that a combination of several biomarkers is needed to achieve adequate sensitivity and specificity.

Biomarker Prioritization - Biomarker discovery projects often generate a longer list of candidates than is practical to test with current methods. Since the process of testing biomarkers is extremely time and cost intensive, it is important to prioritize which biomarkers are evaluated in this next stage. Canary Foundation Science Team employs a variety of theoretical and experimental approaches to prioritize biomarkers.

Biomarker Qualification - Biomarker qualification is the process of testing whether or not a candidate biomarker is found at different levels in cancer patients versus non-diseased people (see "control subjects").

Control Subjects - Control subjects are individuals who do not have the cancer we are studying. These subjects are needed in order to compare biomarker levels with those individuals who do have the cancer of interest. For a test for ovarian cancer, the control cases would include not only healthy individuals but also individuals with other cancers or other non-cancer diseases.

Diagnostic Test - A diagnostic test is any test that is used to detect the presence of a disease or other health perturbation. There are many types of diagnostic tests from blood tests (like a PSA test for prostate cancer) to imaging tests (like mammography for breast cancer) to urine tests for pregnancy.

Epigenomics - Epigenomics is global analysis of epigenetic changes across the entire genome. Epigenetic changes (such as DNA methylation) affect gene expression without altering the DNA sequence.

Genomics - The study of the complete genetic material, including genes and their functions, of an organism. [definition from NCI]

Prospective Study - A research study that follows individuals over time, and compares samples from, groups of individuals who are alike in many ways but differ by a certain characteristic and compares them for a particular outcome. An example of a prospective study is one that follows a set of female nurses who smoke and another set that does not smoke and compares rates of development of lethal lung cancer between those two groups. [definition from NCI]

Proteomics - Proteomics is the study of the structure and function of proteins in the body, including the way they work and interact with each other inside cells. [definition from NCI] Proteins are encoded by genes.

Retrospective Study - A study that compares samples collected in the past from two groups of people: those with the disease or condition under study (cases) and a very similar group of people who do not have the disease or condition (controls). For example, one group may have cancer and one group may be healthy, or one group may have lethal cancer and another group may have non-lethal cancer. Also called a case-control study. [definition from NCI]

Sensitivity - When referring to a medical test, sensitivity refers to the percentage of people who test positive for a specific disease among a group of people who have the disease. No test has 100% sensitivity because some people who have the disease will test negative for it (false negatives).

Specificity - When referring to a medical test, specificity refers to the percentage of people who test negative for a specific disease among a group of people who do not have the disease. No test is 100% specific because some people who do not have the disease will test positive for it (false positive).

Translation - Translation (or translational research) is the process of taking discoveries made by researchers and applying them to clinical practice in order to benefit patients.

Validation - The process of verifying that a biomarker (or biomarker panel) reproducibly distinguishes cancer from non-cancer (or non-lethal cancer). In order to be validated, biomarkers must pass through multiple phases of testing. Biomarkers undergo initial qualification through a retrospective study, whereby patients with disease are compared to patients without disease and relevant non-disease conditions. Biomarkers that pass those tests are then evaluated for their ability to detect disease before it becomes clinically apparent through testing on samples collected in prospective studies. Final validation phases involve testing the biomarker(s) in prospective screening studies and in randomized clinical trials.