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Stem cells are undifferentiated cells that can differentiate into specialized cells when certain genes become activated later in development. There are two types of stem cells: embryonic and adult stem cells. Embryonic stems cells are classified as totipotent, meaning they can give rise to all parts of both an embryo and an adult. These cells are like their name, derived from four to five day old human embryos; they come from the blastocyst phase of development. On the other hand, adult stem cells, also known as somatic stem cells are classified as pluripotent, meaning they can give rise to many but not all parts of an organism, such as certain cells in the brain. These cells are present and exist in the body after embryonic development. They are found in certain tissues since they are very specialized cells. Some example of adult stem cells location in tissues include the brain, blood skeletal muscles, the liver, bone marrow, blood vessels, and skin.
Can stem cells help with certain cancer treatments? The answer is yes. Stem cells do play a major role in the aftermath of some late stage cancer treatments. With certain cancers, including leukemias, multiple myeloma, and some lymphomas, late stage cancer treatments such as radiation and chemo, can damage the body to a great degree. Many cells in the body are destroyed by these treatments or simply by cancer itself, and stem cells are used to replace the bone marrow. Depending on the origin of the stem cells the procedure may be called a Bone Marrow Transplant (BMT), a Peripheral Blood Stem Cell Transplant, or a Cord Blood Transplant, and all can simply be called Hematopoietic Stem Cell Transplants.
Stem cells and Hematopoietic Stem Cell Transplants are vital for humans to survive because we need all three blood cell types to be able to live. These three blood cells include red blood cells, white blood cells, and platelets. These cells are used in the transplants given to cancer patients. Red blood cells (erythrocytes) carry oxygen from the lungs to other parts of the body and bring carbon dioxide back to the lungs to be exhaled out of the body. If one does not have enough red blood cells they are said to have anemia, making them look pale and feel short of breath, weak, and tired. White blood cells (leucocytes) fight against infections caused by viruses, fungi, and bacteria. The different types of white blood cells include Neutrophils, which are most important in fighting bacterial infections, and Lymphocytes which include different types of cells of its own (T cells, B cells, and NK cells); lymphocytes make antibodies to fight infections. Finally, Platelets help blood to clot and seal damaged blood vessels, both of which help to stop bleeding. If the human body is low on any of these cells counts, especially with cancer, then the chance of surviving is very slim; therefore, stem cell transplants after rough rounds of radiation and chemo are so important—they give higher chance of survival by replacing these cells that are destroyed.
Stem cells can either be derived from the cancer patient or donated. Although, if using donor stem cells, the cells need to closely match the cancer patient’s stem cells. Usually having a sibling donor would be the closest and easiest match, but if the patient does not have a sibling donor, then they can get matched to an unrelated donor, receiving a treatment called a matched unrelated donor transplant (MUD Transplant). These transplants can either be matching donor stem cells or a mismatched transplant, meaning one can have a transplant without being a perfect match. To learn more about donor cells and transplants click here, and if interested in helping a cancer patient, call a local hospital to make an appointment at their lab.