The Oncogene: A Key Factor in the Development of Cancer
Under normal conditions, the DNA in a gene instructs the cell in which the gene resides to produce certain proteins in certain amounts.
If the cell is exposed to radiation or to certain drugs or chemicals, the DNA can break apart.
The separated DNA is then likely to recombine incorrectly, which may result in the formation of an oncogene.
Once the oncogene has been created, the cell may produce unusually large amounts of one of its normal proteins (or an aberrant protein). This causes the cell to transform into a cancer cell that looks very different from its former self .
When the cancer cell replicates its DNA and divides, each daughter cell
possesses an identical oncogene. As this process of replication and division
continues, cancer spreads. |