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Cancer and the Immune System

Elements of lifestyle, in particular the type of diet that people eat, can contribute to the cause of many cancers; your genes do play a part in whether you get
cancer, or what type of cancer you get, however, the things that cause cancer the most are not related to your genetics [1].

Cancer is not a single disease. The word ‘cancer’ describes a family of diseases that are related by features. For example a breast cell is different to a liver cell;
likewise, a breast cancer cell is different to a liver cancer cell. However, different cancers are related by mechanisms and features that make them cancerous [2].

There are hallmarks of cancer cells, which are features that tumour cells have:

‐ Evading apoptosis; (apoptosis is programmed cell death ‐ how the body normally removes ‘bad’ cells)
‐ Self‐sufficiency in growth signals; (usually cells rely on growth signals from other cells; cancer cells can produce their own for themselves)
‐ Insensitivity to anti‐growth signals; (cancer cells can ‘ignore’ or ‘avoid’ signals to stop growing)
‐ Tissue invasion and metastasis; (this is the cancer cells ability to move to other parts of the body and start growing there)
‐ Limitless replicative potential
‐ Sustained angiogenesis; [3] (angiogenesis is the process of growing new capillaries, veins and arteries; tumours need a blood supply to grow over a certain size)
‐ Avoidance of the immune system
‐ Advanced anabolic metabolism
‐ Disabled autophagy [4] (autophagy is similar to apoptosis, another form of programmed cell death)

The inflammatory process is one that is integral in the maintenance of health, and can arise as a result of trauma, infection, autoimmune interactions or
environmental toxicity [5]. Usually, when inflammation occurs, the immune cells involved do their job and then disperse. If they don’t disperse, they can continue
their activity when it is not wanted, and if this happens over a long period of time, these immune cells can damage the body [6, 7]. This damage can ultimately turn
into cancer [8].