Damascus Steel in the Battle against Cancer
In 1187, a vast Arabian army lead by the legendary Kurdish general Saladin annihilated a large Crusader army, including a battalion of well-armoured knights, at an infamous battle known as the “Horns of Hattin”. When battle ceased, over 15,000 Crusaders lay dead with only a handful of casualties on Saladin’s side. The secret to Saladin’s stunning victory? Nanotechnology. Saladin’s army was equipped with blades forged from ‘Damascus Steel’. These blades were renowned across the world for their mythical strength and sharpness, and were stronger than even the toughest of European armour.
Only in the last few years have the secrets of the famed ‘Damascus Steel’ been revealed. Crystallography studies have shown that nanowires and carbon nanotubes were incorporated into the structure of the metal during the forging process, giving it its strength. It seems that 800 years ago, albeit unwittingly, Arabian swordsmiths had taken the first steps into the world of nanotechnology.
Sadly, much of the knowledge and expertise of the forging process disappeared in the 17th century and it wasn’t until the latter part of the 20th century that interest in nanotechnology was rekindled - this time not purely for the purposes of war and conquest, but for medicine and science.
Nanotechnology must be one of these words in our modern lexicon that has been bandied around so much, its true meaning is somewhat hazy. So let’s begin with a definition: nanotechnology, strictly speaking, refers to the study and science of any device or object that is between 1 and 100 nanometers (nm) in size. To put things into perspective, a human hair is 60,000 nm in width.
Nanotechnology in the 21st century has shown promise in various fields of human endeavour, ranging from electronic and mechanical engineering to chemistry. However, one of the most promising avenues of research thus far has been in medicine and in particular in the detection and treatment of cancer.
The shadow cancer casts on humanity needs no introduction. It is THE leading cause of death worldwide, accounting for almost 15% of deaths every year and causing untold misery and suffering to many more millions. What makes this plight even more tragic is that better detection and more efficient treatment could prevent a third of these deaths. This is where many scientists and doctors believe nanotechnology will play an important, if not vital part.
The key to successfully treating cancer is to detect it as early as possible. Nipping the bud before it has time to grow means that the disease can be treated before it has had time to spread to other organs. This would not only reduce the dose of harmful chemotherapy, but lead to a better chance of survival.
If you, the reader, have the misfortune of being diagnosed with a “suspected neoplasm” (medicspeak for cancer), one of the most common methods of confirming the diagnosis would be by a CT scan. Although an excellent diagnostic test, the cancerous mass has to reach a certain size before it is visible on a CT scanner and can be confirmed by the radiologist. In some cases, this may already be too late as the cancer may have reached a stage where treatment will not be beneficial. In other cases treatment would have been much more effective had the cancer been caught earlier. To combat this problem, scientists do not need to think bigger, but smaller – much much smaller.
Cancer cells, by their very nature, produce proteins and other cellular components that normal healthy cells do not, thus giving a unique signal that betrays their deadly secret. Scientists can utilise this signal by constructing a very thin wire – usually around 1-2 nanometres in diameter – that is coated in antibodies against specific proteins that are only expressed by cancerous cells. When these proteins bind to the antibodies, it causes a very subtle change in the nanowires structure. This change in turn generates a tiny impulse of electricity, that although harmless to the cancer cells themselves, allow scientists to detect the tiniest amounts of abnormal proteins, giving a 100-fold increase in detection accuracy over current conventional methods.
Another method, again using antibodies, is called the nano-cantilever. These are long, thin strips of nano-material, coated with highly specific antibodies against cancer proteins. Here, proteins released exclusively from cancer cells again bind to these strips causing the entire molecule to bend around 10-20 nanometres. This minute change is detected by powerful lasers meaning that scientists can detect cancer markers 20 times below the level at which they affect the function of the body or cause symptoms.
Such diagnostic tests would be revolutionary in detecting many types of cancers. For example, some lung cancers may grow in the body for up to 15 years before they cause any symptoms. Clearly, early detection using nano-cantilevers, could help save countless lives in the future.
However, detecting cancer in its earliest stage is only half the story as far as the successful management of cancer is concerned. Unless the treatment of cancer improves dramatically, the efforts made in early detection will be futile.
Although often effective, current treatments against cancers such as chemotherapy are fundamentally flawed. They destroy the body’s healthy tissues as well as the intended cancerous target, causing the notorious side-effects of chemotherapy - like deploying the Fat Man to target a solitary renegade. In fact, the side-effects can be so severe that some patients refuse any more treatment.
What is needed then is a method of treatment that targets ONLY the cancerous cells, leaving the body’s healthy cells unharmed, in the same way a laser guided missile can annihilate an individual enemy redoubt, while leaving the surrounding buildings unscathed. This is where nanotechnology can yet again step up to the mark.
A human cell is around 15,000 nanometres in diameter, and thus much larger than a nano-device. This means, if designed appropriately, the nano-devices can enter and leave a cell, cancerous or not, without causing too many problems. We have already learned that cancerous cells express proteins on their outer surfaces that are not found in normal cells. A new breed of nano-devices does not merely utilise this information to detect cancers, but to target and destroy them.
Although the research is still in its infancy, this novel idea is simple but elegant. The nano-devices are spherical structures that have a hollow core filled with deadly chemicals and drugs. Similar to the nano-cantilevers, the devices have proteins that can only bind to the complementary proteins on the surface of the cancer cells. These nano-devices can then be injected into the patients’ blood, just like any conventional drug. Once inside the bloodstream, they can make their way towards the cancerous mass and, by interacting with the surface proteins of the cell, enter the cell’s core.
Now the drug is primed and ready to do its work. The spheres will release their load when low doses of radiation, which act as a trigger, are passed through the patient, killing only the cancerous cells that incorporated the nano-devices, while leaving the surrounding tissue completely unharmed.
The advantages here are two-fold. Firstly, it leaves the healthy tissues unharmed, so the side-effects are markedly reduced. Secondly, since the drugs are released in a contained environment, in the cytoplasm of the cancerous cell, a higher equivalent dose of medication can be given. This means a greater chance of complete eradication and reduces the risk of the cancer reappearing, which is always a concern with conventional regimens.
It is clear that nanotechnology is progressing and developing at break-neck speeds and holds great promises for the future not only in medicine, but in many other disciplines as well. However, there is definitely a case for vigilance and patience. On the whole, the steps taken have been promising and many may wonder why these treatments are not already being offered to the masses. The answer is simple. A success in a small scale study does not guarantee similar results in worldwide initiatives. Moreover, these inventions are so groundbreaking, it simply would not be ethical to mass produce them without stringent checks to ensure it is safe in the long term. Furthermore, scientists also have to proceed with caution as one tiny mishap will cause reverberations throughout the world and could set the field back many years while casting long shadow on the public’s trust of new technology.
There is no doubt however, that within the next 50 years, nanotechnology will revolutionise how medicine is practised in the same way ‘Damascus Steel’ transformed the medieval battlefields and will undoubtedly challenge our long-held stances and beliefs on so-called incurable diseases.