Byetta Lawsuit: At any moment, the great majority of cells in our body are in a quiescent state. Only in tissues that renew themselves constantly, such as the colonic epithelium, the bone marrow (which generates new blood cells), and the skin, does one find large numbers of cells actively growing and dividing. The cancer cell is a renegade. Unlike their normal counterparts, cancer cells disregard the needs of the community of cells around them. Cancer cells are only interested in their own proliferative advantage. They are selfish and very unsociable. Most important, unlike normal cells, they have learned to grow without any prompting from the community of cells around them.
In principle, information regulating growth might be passed from one cell to another by electrical signals or small organic molecules. For various reasons, however, evolution has solved this problem in another way. In all complex, multicellular organisms, this information is conveyed by small, soluble protein molecules termed growth factors. A growth factor protein is released by one cell, moves through intercellular space, and ultimately impinges on its target—another cell. The target cell then responds by initiating a program of growth and division.
Several types of cancer cells seem to have shed their normal complement of TGF-B receptors. It is unclear how retinoblastoma cells, for example, lose these receptors, but this loss provides clear growth advantage to these cells. Normal retinal cells experience substantial levels of TGF-B in the back of the eye. Lacking appropriate receptors, the retinoblastoma tumor cells are oblivious to TGF-B and therefore ignore its orders to stop.
Byetta Lawsuit