· Continue multiplying
§ Healthy cells stop multiplying in the presence of sufficient quantity of cells. Cancer cells, conversely, contain mutated genes. Changes in a cell’s genes causes miscomprehension of instructions, and therefore abnormal proliferation. On average, it takes about six mutations before a normal cell turns into a cancer cell.
o Normal cells ‘grow up’ and specialize into differentiated cells. Cancer cells, in contrast, remain undifferentiated because they reproduce rapidly before the cell has a chance to mature. The grade of cancer normally levels to the degree of cell maturity. With 1 being the least aggressive and 3 being the most aggressive.
o Cancer cells, contrasting with normal cells do not respond to chemical signals from other nearby cells. Hence, they are unable to know when they’ve reached their boundaries and should stop growing.
· Avoid apoptosis
o When cells get damaged or old, they either get repaired or undergo apoptosis (cell death). Cancer cells, however, are missing or having an inactive or abnormal P53 protein which advises them on which to do. They are, consequently, allowed to multiply and reproduce as per normal.
· Evade the immune system
o Cancer cells are able to elude death either by avoiding detection or through secretion of certain chemicals that deactivate immune cells that come on site. Normal cells, however, lack the protection cancer cells possess and can be removed.
o Normal cells create cell-cell contact through the secretion of a sticky substance, Claudin-5, made of proteins on the surface of their cells. These proteins make contact with proteins, akin to theirs, on other cells in order to stick together as a group. Cancer cells, however, can “float away” to locations nearby or (through the systemic or lymphatic system) to faraway regions in the body, due to their inability to make these sticky substances. There, they begin to grow and create new tumors afar from the original tumor.
· Influence normal cells
o Cancer cells are able to signal nearby normal cells through angiogenic factors to encourage formation of blood vessels thereby supplying tumors with oxygen and nutrients, needed for growth.