A new molecule extracted from frogs could be a potential remedy for brain cancer.
Frogsâ€™ eggs contain molecules with special cancer curing properties.
Some of the best drugs that we have were found in nature. Conventional wisdom suggests that nature is still the best place to look for drugs to fight even serious diseases. The only problem is we do not know quite where to look. Large forests have been a natural choice, but the living world extends beyond plants. How many will look in frogsâ€™ eggs?
Twenty years ago, Alfacell Corporation, a small drug discovery company in New Jersey, extracted a type of molecule called ribonuclease from frogsâ€™ eggs. This is now in clinical trials as a treatment for cancer. Recently, another form of the molecule â€” called Amphiminase â€” has been found to be even better in treating cancer, particularly difficult forms of it like brain cancer. It has a special property of recognising and attacking only cancer cells, suggesting that it could be non-toxic. â€œThis is a very exciting molecule,â€ says Ravi Acharya, professor of biochemistry at the University of Bath in the UK.
Acharya, along with scientists at the Alfacell Corporation, recently synthesised this molecule in the laboratory and studied its structure and chemical properties in detail. It belongs to a class of molecules called ribonucleases, so called because they chop up another class of molecules called ribonucleic acid (RNA). RNA is vital to protein synthesis, and hence to the survival of any cell. When RNA needs to be used, the cell smothers the ribonucleases with other molecules and stops them from functioning, thus leaving the RNA free to do its job.
When Amphiminase enters a cancer cell, or any cell, it wrecks the protein synthesis machinery by inactivating the RNA. However, it enters only the cancer cells because they are coated with sugar molecules that Amphiminase recognises. The interesting and useful fact is that it crosses the blood-brain barrier and goes inside the brain. Cancer of the brain has been particularly resistant to treatment with drugs because most molecules do not cross the blood-brain barrier.
The drug has been found very promising in pre-clinical trials. Yet, from pre-clinical trials to the market is a long way. The first compound that Alfacell isolated is now in different stages of clinical trials for treating different kinds of cancer. Ribonucleases are a good candidate for drug companies. Alok Srivastava, president of Nidaan, an anti-cancer start-up at the University of California, San Francisco, says, â€œSince it destroys the RNA, it can be effective in many kinds of cancers.â€
Sources:The Telegraph (Kolkata,India)