Doctors say herbal blend can help cancer patients

 

 

Abram Katz , Register Science Editor

 

Yale University, the Ivy League bastion of Western science, is turning to ancient Chinese formulas to develop new medicines for the 21st century.

Already physicians have demonstrated that an 1,800-year-old Chinese recipe of four plants can apparently ease the side effects of chemotherapy while boosting the healing power of the anti-cancer drug.

 

These intriguing preliminary results must be expanded and reconfirmed, doctors said, but a crucial principle is clear — combinations of compounds could be the key to treating a variety of intractable diseases.  Specifically, researchers believe that modernized "polychemical" Chinese remedies hold hope for diseases of aging like cancer, Alzheimer’s disease and other neurodegenerative diseases.

Yale is among a handful of American institutions exploring Chinese medicine and may be the closest to bringing an FDA-approved drug into clinical use.  Yale scientists have established PhytoCeutica Inc. in New Haven as a base of business operations and have already developed a unique method to ensure chemically consistent products.

The very antiquity of traditional Chinese medicine supports its effectiveness, said Dr. Edward Chu, chief of medical oncology at the Yale Cancer Center.

"Herbs have been used in the Orient for 2,000 years with clear efficacy. Experience was passed down from generation to generation to generation.   My great-grandfather was a Chinese herbalist," Chu said.  But Chu is hardly a supplement store flake.

Chu is internationally recognized for his research on why abnormal cells proliferate and sprout into cancer. He is currently studying novel treatments for colon cancer.  Chu hopes to apply the same rigorous research methodology on herbal medicines.

"The essence of Chinese medicine is multiple ingredients and all are key. You may need two ingredients for efficacy and two to prevent toxicity," he said.

This is more than mere theory.  Chu and colleagues are working on a traditional medicine that they call PHY906.

PHY906 interested Chu because the medicine is traditionally used to ease gastrointestinal problems — the same kinds that plague people receiving chemotherapy for colon cancer.

Yale pharmacology professor Yung-Chi Cheng said the research team did not want to reveal the mixture’s commercial name.

This is because identically named products from several sources may have completely different ingredients, or may vary significantly from batch to batch.  In fact, Chinese medicine can only be integrated into the modern system if the compounds are rigidly consistent, Chu and Cheng said.  And that is a whole challenge unto itself.

Cheng said there was every reason to believe PHY906 would work.

"Chinese medicine has been used for ages and keeps evolving. Many formulas are used today. If it were useless, people wouldn’t still use it," he said.

"Modern medicine is only 50 years old, so there’s a big gap. You either deny the history or you take advantage of its historical use," Cheng said.  Eventually, Chinese medicine will complement modern medicine, he said.  Western physicians are suspicious of Chinese medicine because it was developed empirically, rather than experimentally, Cheng said.

"Even if you have a medicine that is evidence based, if you can’t make it consistent, the material is not a medicine," Cheng said.

"If we can overcome those two issues, then Chinese medicine may be useful for unmet clinical needs," he said.

Yale conducted a clinical test of PHY906 on patients receiving chemotherapy. Out of 30 patients, 17 were evaluated, Cheng said.
The patients experienced less vomiting, nausea and diarrhea. And tumor progression was halted in all but two patients.

"This is very encouraging. It is a preliminary result," Cheng said.

Another study of PHY906 is under way on patients with liver cancer at Yale and the City of Hope National Medical Center in Los Angeles.  The mixture seems to aid chemotherapy by increasing absorption in cells. PHY906 also apparently affects a protein involved in regulating cell proliferation, transformation and tumor development.

"This may be a totally novel way of treating diseases," Cheng said.

Cheng, Chu and PhytoCeutica analyzed the components of PHY906 using mass spectrometry and liquid chromatography. Both methods basically separate chemicals by molecular weight.  PHY906 contains about 150 different chemicals, about 90 of which have been identified. Eight of the compounds seem essential to the mixture’s effectiveness. 

PhytoCeutica has developed a new way to test the consistency of the ingredients they will combine to produce PHY906.  A human cell culture is exposed to compounds.  The cells respond by producing proteins. During protein synthesis, messenger RNA is formed.

Robert Tilton, vice president of science and technology at PhytoCeutica, said the RNA is then traced back to the DNA from which is was encoded, using conventional DNA-chip technology.  About 200 to 300 genes out of 30,000 are either activated or inhibited by the mixture, Tilton said.

"We can quickly generate a unique gene pattern.  The novelty is to use this for quality control," he said.

Eventually, the technique will be useful in determining the mixture’s biological activity, but that work could take several years, Tilton said.  Meanwhile, the gene pattern can guarantee consistency to better than 90 percent.

"We have insight into how it’s working. There are multiple mechanisms," he said.

The FDA has provisions to approve botanicals as prescription drugs, and PHY906 is going through the conventional testing process, he said.

"We want to shift the focus from single molecules to collections of molecules to add a new level to Western medicine," Tilton said.

"In a way, we’re rediscovering the past, but with rigorous methodology," he said.      ©New Haven Register 2005

- Reprinted with the permission of the New Haven Register