The immune system plays a crucial role in identifying and eliminating abnormal cells, including cancer cells. However, cancer cells can develop mechanisms to evade the immune system’s surveillance and attack, allowing them to proliferate and form tumors.
Following are some key points describing the relationship between cancer and the immune system:
- Immune Surveillance: There is constant patrolling inside the body by immune system for any cells that display abnormal characteristics, such as those found in cancer. Immune cells like T cells and natural killer (NK) cells can recognize and eliminate these abnormal cells.
- Tumor Antigens: Unique molecules / antigens that are not present on normal cell are often produced by cancer cells. These antigens can be recognized by immune cells, particularly T cells, as signals of potential threats.
- Immune Response: When immune cells recognize these cancer cells as foreign or abnormal, they initiate an immune response. T cells can directly attack on these cancer cells, while other immune cells start releasing signaling molecules (cytokines) that attract more immune cells to the site of the tumor.
- Immune Evasion: Cancer cells can develop various strategies to overcome immune detection and destruction. For example, they might downregulate the expression of certain antigens, inhibit immune cell activity, or even express molecules that induce immune tolerance.
- Cancer and Inflammation: Chronic inflammation can also increase the risk of cancer development. Certain immune responses, especially chronic in nature can lead to tissue damage and mutations which may lead to cancer initiation and This is why conditions associated with chronic inflammation, such as inflammatory bowel disease, are linked to an increased cancer risk.