New Scientist have done it again. The 13th October 2012 issue has a major article entitled “ENDING CANCER”. I couldn’t help but feel inspired by the article so here’s what I took from it.
The Old Vision of Cancer
No hair, skinny physique and pale skin is the lingering image that most people have in their mind when someone says “cancer”. It is an image we have learnt to associate with cancer patients ever since chemotherapy and radiotherapy became normal treatment for cancer.
The mechanism of action of these treatments isn’t specific and they are used as they focus mainly on rapidly dividing cells. Numbers of red and white blood cells drop and produce pallid skin and ease of contracting illness. Hair follicles die and the strands drop out, meaning a loss of hair. Stomach lining cells become irritated producing nausea and vomiting. These are just a few examples.
Yet, for a while now, this image has quickly become old-fashioned. These side effects are beginning to fade as our knowledge of new therapies is becoming clearer.
The New Wave
The current first line of treatments unfortunately produce some form of long-term side effect. This is due to their lack of specificity. The idea therefore is to produce a treatment that IS specific.
One approach involves nanotechnology – something that most people would link more to science-fiction that to medicinal practice. The idea is to use nanoparticles (incredibly small materials) to transport chemo drugs straight to their designated targets. Instead of running rampant in a patient’s bloodstream, the nanoparticles collect at the site of a tumour – due to the “leaky” nature of tumour blood vessels – and therefore deliver the chemo drug directly to the cells you want to attack, causing as little collateral damage to any surrounding healthy cells.
A further expansion on this idea is to connect the nanoparticle to an antibody that is specific to a cancer cell surface protein. Antibodies are part of the specific immune response to foreign material found in the body and have been manipulated and designed for many years now. In this way, a cancer cell displaying a protein that is targeted by an antibody then the connected nanoparticle/chemo drug hybrid can be delivered with true specificity to a persons tumour.
A further theory is to evoke a specific immune response by creating a “cancer vaccine”. By introducing a specific genetic sequence into a patient’s cell DNA, it is theoretically possible to induce the patients cells to begin constructing cancer surface proteins. The idea then is that the patient’s immune system will detect this and destroy the cell, creating antibodies specific to that cell protein. Then, if cells begin displaying that protein at a future date, then the antibodies will be on hand to destroy any cancerous cells quickly without the need for toxic drugs. This effect is much the same as what occurs with other vaccines; inject the body with a (often dead) foreign protein to produce an immune response. This is being hailed as possibly the most promising idea for advancing cancer drugs. Whether the idea of creating cancerous proteins inside a healthy human being is an idea that will catch on is a different question.
Other therapies are being proposed to harness the presence of bacteria that are already present in human beings. If we can manipulate bacterial cells to attack a known cancer protein then they can theoretically do all the work for us. Even better, some bacteria strains are known to gather at tumours, therefore there is no need to worry about where the bacteria will end up. Another mortal enemy of ours – viruses – can be manufactured to insert gene sequences into cancer cells, the desired effect being that they can force the cell to construct viruses until bursting point.
Not For a While Yet Though…
There are so many potential treatments against cancer on the horizon – these discussed are only a few. The unfortunate truth is that they will take AT LEAST another decade or so before they even hit the market, if their trials are successful that is. They are however causing much excitement as they truly can change the death rates associated with cancer.
Video courtesy of YouTube.