A recent report in the New York Times said a cure for cancer could be on the horizon.
In the days following the report, however, hopes were dashed by a host of cautionary stories aimed at reducing what many feared were unrealistically high expectations.
So what is the truth? As with most things, the answer is somewhat more complex. At issue is the potential of a new class of drugs which produce anti-angiogenesis. Angiogenesis is the formulation of new blood vessels. In a healthy adult, this normally only takes place at certain times, such as during pregnancy or when healing from some trauma. However, new blood vessels can also be formed as part of a disease, such as diabetic retinopathy and macular degeneration.
When cancer tumors form, they also spark angiogenesis to feed their voracious appetite for blood. Cancer researchers believe that inhibiting the formation of new blood vessels will cut off the flow of blood to the tumor and essentially starve it to death. This avenue of investigation is so promising that some 33 patents have been approved for drugs with anti-angiogenic properties. There are, however, a number of ways in which anti-angiogenesis can be accomplished.
One line of research is seeking ways to keep the cells which line capillaries from reproducing. Such reproduction is part of angiogenesis. Another approach is to block the action of enzymes called metalloproteases, which are essential to blood vessel formation. Both avenues of research have reached the stage of having human clinical trials.
The drugs, which were the subject of the New York Times article, are the result of still another line of research in inhibiting angiogenesis. Researchers have isolated two proteins (angiostatin and endostatin) produced in tumors that are angiogenic inhibitors. While it was known that these two proteins individually were of some value in suppressing tumors, Dr. Judah Follaran of Children's Hospital and Harvard Medical School in Boston decided to use them together. That research was conducted on mice and found that the combination appeared to eliminate all types of tumors without side effects. What makes these results so exciting is that the formulation appears to be effective against all types of cancers, something not usually seen with anticancer drugs.
As promising as it is, there is still a long road to travel before it is available to patients. There is a lengthy process a drug must undergo before it is even submitted to the FDA for approval.
Following the completion of the animal studies such as those conducted on the mice, the developer must apply to the FDA for what is called an investigational new drug application. This makes it possible to conduct human experiments, which take place in three phases.
- Tests are conducted on a small group (20-80) of healthy human volunteers. The purpose of this phase is to confirm the drug's safety.
- Tests on a larger number of volunteers (usually in the hundreds) are then undertaken to determine both the safety and effectiveness of the drug.
- Finally, large clinical trials (1,000-3,000 patients) are conducted to confirm that the drug is effective and to monitor its long-term effects. At least two trials must be conducted in this phase.
Once these processes have been completed, the company can submit the new drug application for marketing. Only about one out of a thousand compounds initially tested will ever make it to the point of submitting a new drug application. Further, only one in five new drug applications are approved.
In short, while the new research is promising, and indeed holds out the hope of providing a uniquely effective way of treating all forms of cancer, it is going to be years before the research produces a medicine that can be administered to human beings. This is not to say that the news doesn't warrant attention. It appears that a real breakthrough has been made. It is important though to temper our patients' enthusiasm with a dose of reality, and understand that much remains to be done.
The best approach is prevention. A healthy lifestyle, consisting of proper nutrition, correct exercise and healthy nervous and immune systems is our best bet. Chiropractors have always been at the forefront of natural health, and a healthy body is the best weapon.