Cancer is caused when there is a breakdown in the normal processes that regulate cell numbers in some part of the body. Everything about our physiology is tightly controlled from the moment of conception but as we get older, or take risks with our life-style, or suffer from a genetic mutation, the machinery can stop working perfectly. There is also a strong connection between infectious diseases and cancer. The parasite I work on most – schistosoma – can cause bladder cancer because its eggs pass through the bladder wall and create problems for the tissues that comprise the bladder. Many viruses are also associated with different types of cancer as they disrupt cellular machinery.
In terms of cures there is no one rule for everything. If caught early then different interventions such as chemotherapy or radiotherapy can help. These days there are sophisticated laboratory experiments underway to design ‘smarter’ medicines that target cancer cells more directly without causing damage to other cells.
Cancer is a disease defined by uncontrolled proliferation of abnormal cells and these cells then disrupt the normal function of the body. Normal cells have mechanisms to control what the cells do or how the cells grow and proliferate and this is usually imprinted in our genetic code – although recently it appears to be beyond the genetic code as well. In cancer, these mechanisms kind of break down (e.g. by mutation in the genetic code which control the mechanisms) and hence the cells lose their control.
Each type of cancers are different and there is unlikely to be one cure fit all for them. There are some existing therapy includes using drug that target rapidly dividing cells (a hallmark of cancer cells) but this can also damage normal non-cancer cells too. THen there are also more specific treatment being developed e.g. using immune cells to recognise specifically cancer cells.
Some current research now try to find out the “signature” of each cancer type so that they can come up with specific treatment for each type, which would help patients to not need to go through treatment that might not work for their disease 🙂