Recently, researchers have discovered beta-cateninA multi-functional protein that helps cells react to signals. The protein also turns on genes that make cells divide. as a new target for Mixed Lineage LeukemiaA cancer affecting the cells that develop into white or red blood cells. Both of these cell types originate from stem cells in bone marrow. Red blood cells function to carry oxygen to our tissues and the white cells (leukocytes) are part of our immune system. The cancerous cells often accumulate in the blood. (MLL) treatment. This form of leukemia is caused by mutations in the MLL geneA stretch of DNA that leads to the production of an RNA. The RNA is produced during the process of transcription. This RNA can be used to guide the formation of a protein via translation or can be used directly in the cell. and causes approximately 70% of infant leukaemias and 10% of adult acute leukemias. With currently available therapies, only 50% of children with this leukemia survive for longer than two years. Studies at King’s College London revealed the role of one oncogeneA defective gene that is involved in triggering cancer cell growth. Oncogenes are altered forms of genes that normally are involved stimulating cell division. These normal genes are mutated and function in an inappropriate manner in cancer cells. An analogy would be that a mutated oncogene is like a car's gas pedal stuck in the on position. All forms of cancer have one or more mutant oncogenes. Examples of oncogenes that are altered in many cancers are myc, ras and Her-2/neu. Contrast with 'tumor suppressor'., beta-catenin, in promoting the development of leukemic stem cells. When beta-catenin was suppressed, there was reduced leukemic stem cellCells capable of developing into more than one cell type. All of the cells in a human body come from the division and subsequent differentiation of a single cell, formed from the fusion of an egg and sperm. This original cell has the capability to form any cell type and is called totipotent. As tissues develop the cells lose the ability to form all other tissues, and become 'committed' to forming only one or a few cell types. These stem cells are called pluripotent. An example are bone marrow cells that form many different kinds of blood cells. Stem cell replacement allows for the pluripotent stem cells in bone marrow to be replaced after high doses of chemotherapy. Many fully differentiated cells are not capable of cell division and are replaced when they die by the division of stem cells in that tissue. Many forms of cancer are thought to be the result of abnormal division of stem cells. growth, delayed onset of leukemia, and even reversion of stem cells to a pre-leukemic state. The studies showed that suppressing beta-catenin in human MLL leukemic stem cells made drug resistant cells sensitive to treatment. Normal blood cells do not require beta-catenin so it could be an excellent target for selectively attacking cancer cells.
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