Important Background Information

We have provided a brief overview of the terms and science surrounding those terms for those people who want more depth.

Tumor markers:

Tumor markers (also called biomarkers) are substances found in the blood, urine, stool, or tissue that are produced by cancer cells. Tumor markers may indicate or suggest the presence of cancer. Different tumor markers may be present for different types of cancer.

The ideal marker would be a blood test for cancer in which a positive result would only occur only if there were a cancer present. This ideal marker would also indicate the stage of the cancer and possible response to treatment. In addition, it, would be easy to measure.

Tumor markers can be used for several purposes:
	Screening a health population or a high-risk population for the presence of cancer Making an early diagnosis of a specific type of cancer Determining the probable outcome of a patient’s disease Monitoring a patient during the course of surgery, radiation therapy, or chemotherapy Monitoring a patient in remission
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No current test meets all these requirements. Most tests today have problems with false positive and false negative results. For more information about this click here:

Pharmacogenetics is a specialty field within the study of genomics. It is generally regarded as the study of genetic variation that can affect an individual’s responses to certain drugs. Pharmacogenetics uses information about a person's genetic makeup, or genome, to help determine the drugs that are likely to work best for that particular person and/or that may be likely to lead to certain adverse effects.

For certain drugs, pharmacogenetics may help to determine whether patients are rapid or slow metabolizers (referring to how long the drug stays in your body) as well as whether they are responders or non-responders (meaning whether the drug works for you).

Having the ability to predict a person’s individual response to a drug, both in terms of therapy benefit and the likelihood for adverse events, will play a crucial role in:

• Preventing the use of a drug that is likely to cause serious effects for a particular patient without benefit
• Guiding the selection of optimal therapies that are most likely to benefit a specific patient

Deaths from drug side effects are one of the top ten leading causes of death, so this field is very important.

For decades, scientists and doctors assumed that cancer was caused by irreversible damage to some critical stretch of DNA within one's genome. But in the last few years, a much more complex picture has emerged, one that shows that some cancers are caused by epigenetic changes-tiny chemical tags that accumulate over time and can turn genes on or off rather than mutate them.

The word "epigenetic" literally means "in addition to changes in genetic sequence." It is used to refer to any process that alters gene activity without changing mutating the DNA sequence. Experiments show that epigenetic changes, unlike mutations, can be reversed.

Proteomics is the study of the structure, functions, and interactions of proteins. While genes are the “recipe” of the cell, containing all the instructions for assembly, proteins are the products of these recipes, functioning as the cellular engines that drive both normal and disease physiology.

A breakthrough in cancer treatment was the discovery that tumors “leak” proteins and other molecules into blood, urine, and other accessible body fluids. The greatest promise for the early detection and treatment of cancer is to collect such fluids from patients and test them for the presence of cancer-related molecules, called cancer biomarkers or tumor markers.

• The vast number of proteins that exist in the body can make it difficult to identify and describe them.
• Proteins are continually moving and undergoing changes.
• Proteins exist in a wide range of concentration in the body.
• Lack of standardization – Laboratories across the county collect, store, and study proteins in different ways. This lack of standardization makes it difficult to accurately compare results from one laboratory to another.

Metabolomics is the systematic study of the unique chemical fingerprints that cells leave behind. More specifically, it is the study of how your body responds to drugs, environmental changes and diseases. Metabolomics is an extension of genomics (study of genes) and proteomics (study of proteins).

If metabolomic information could be translated into better diagnostic tests, it might have the potential to impact clinical practice, and it might lead to more targeted biomarkers that improves care.