Refers to tumors, cancer, and other neoplasms.
The origin and development of a tumour.
Part of the DNA that contains genes responsible for cell division and tissue growth. When their expression is uncontrolled, cancer develops. When a normal cell escapes its usual constraint in terms of growth and function, it does so through the action of oncogenes that encode altered forms of hormones or receptors or transcription factors that in turn distort the cell and its function. More than 50 oncogenes have been identified. The effect of oncogene products arises through their differences from their corresponding normal cellular proteins. They may have different rates of synthesis and/or degradation, altered cellular functions, or be resistant to the normal control mechanisms in place that regulate cell function. In order for the cell to become a cancer cell, it must have at least five independent oncogenic events. This is due to the broad spectrum of control mechanisms and the complex cellular processes and signaling mechanisms within the cell. It also explains why the risk of cancer increases with age since time and oncogenic events are needed for the full expression of the cancerous state.
The process to converting a normal cell to a cancer cell.
The production of cancer through the action of biological, chemical, or physical agents.