Glossary of Medical Terms

Failure of the lung to expand (inflate) completely. This may be caused by a blocked airway, a tumor, general anesthesia, pneumonia or other lung infections, lung disease, or long-term bedrest with shallow breathing. Sometimes called a collapsed lung.

A drug that binds to the protein PD-L1 to help immune cells kill cancer cells better and is used to treat many different types of cancer, including cancers that express PD-L1. Atezolizumab is used alone or with other drugs to treat certain types of melanoma, hepatocellular carcinoma (a type of liver cancer), non-small cell lung cancer, small cell lung cancer, breast cancer, and urothelial carcinoma (a type of bladder cancer). It is also being studied in the treatment of other types of cancer. Atezolizumab may block PD-L1 and help the immune system kill cancer cells. It is a type of monoclonal antibody and a type of immune checkpoint inhibitor. Also called Tecentriq.

A type of laboratory mouse that is hairless, lacks a normal thymus gland, and has a defective immune system because of a genetic mutation. Athymic nude mice are often used in cancer research because they do not reject tumor cells, from mice or other species.

A substance being studied in the treatment of certain multiple myelomas and other advanced cancers. Atiprimod may block the growth of tumors and may prevent the growth of new blood vessels that tumors need to grow. Atiprimod is a type of signal transduction inhibitor and a type of antiangiogenesis agent. Also called azaspirane and SK&F106615.

An aggressive (fast-growing) type of T-cell non-Hodgkin lymphoma caused by the human T-cell leukemia virus type 1 (HTLV-1). It is marked by bone and skin lesions, high calcium levels, and enlarged lymph nodes, spleen, and liver. Also called adult T-cell leukemia/lymphoma.

A substance being studied in the treatment of some types of cancer. ATN-161 may prevent the spread of tumor cells and may prevent the growth of new blood vessels that tumors need to grow. It is a type of antiangiogenesis agent.

A substance being studied in the treatment of cancer. It may prevent the growth of new blood vessels that tumors need to grow. ATN-224 also blocks enzymes that cells need to divide and grow, and it may kill cancer cells. It is a type of antiangiogenesis agent and a type of superoxide dismutase inhibitor. Also called SOD1 inhibitor ATN-224.

The smallest part of a substance that cannot be broken down chemically. Each atom has a nucleus (center) made up of protons (positive particles) and neutrons (particles with no charge). Electrons (negative particles) move around the nucleus. Atoms of different elements contain different numbers of protons, neutrons, and electrons.

A drug used to lower the amount of cholesterol in the blood and to prevent stroke, heart attack, and angina (chest pain). It is also being studied in the prevention and treatment of some types of cancer and other conditions. Atorvastatin calcium blocks an enzyme that helps make cholesterol in the body. It also causes an increase in the breakdown of cholesterol. It is a type of HMG-CoA reductase inhibitor and a type of statin. Also called Lipitor.

A substance present in all living cells that provides energy for many metabolic processes and is involved in making RNA. ATP made in the laboratory is being studied in patients with advanced solid tumors to see if it can decrease weight loss and improve muscle strength. Also called adenosine triphosphate.