The AACR Meeting

From March 24 to 28, 2001, I attended the 92nd annual meeting of the American Association for Cancer Research (AACR) in New Orleans, Louisiana. Over 14,000 scientists from every part of the world gathered to review the past year's progress in fighting cancer. There were over 5,000 abstracts including 4,000 poster sessions, at which scientists displayed, discussed and debated their most recent findings. There were also innumerable scientific lectures, panels, receptions and parties.

Scientists poured into the city's gigantic convention center on the Mississippi River and took over dozens of hotels. Everywhere you went---in airports, restaurants, bars, lobbies-you heard snatches of conversation about reagents, enzymes and phenotypes. But if your idea of a scientist is of a middle-aged guy with a crew cut and nerd pack, think again. Today's crop is younger, hipper, and culturally diverse. Blue jeans, tattoos and pierced body parts are not uncommon.

The official leitmotif of the meeting was the genetic revolution and everyone was lauding the success of the Human DNA Project. However, the unanswered question was exactly how this "revolution" will benefit cancer patients? To find out, I attended a forum on "Genetic Therapy: Where Do We Go From Here?" Dr. Savio Woo, immediate past president of the American Society of Gene Therapy (ASGT), revealed how he had attended a government symposium last August on financial conflicts of interest in his field. His bleak conclusion: "Everyone is conflicted."

Researchers, he said, should "avoid financial conflicts of interest at all costs" and ASGT is now trying to implement a "just say no" policy. But he acknowledged that there has been a serious erosion of public trust in gene therapy and a 50 percent reduction in Investigational New Drug (IND) applications.

Call me contrary, but I think the significance of gene therapy has been oversold for today's cancer patients. Since most cancer is environmental in origin, I don't see how tinkering with the genes is going to cure the disease. Are there alternative visions for the future of cancer research? Yes! There is a significant minority at AACR working for the prevention of cancer through nutrition. Some of these scientists even held a news briefing on "Pre-Cancer Prevention, Treatment and Food Substances." They believe that cancer can and should be prevented using nutritional substances and their synthetic analogs.

While they agreed that this "genome business," as they called it, provides them with tools, their main thrust is clearly towards prevention. It is a good omen that the incoming president of AACR is Dr. Waun Ki Hong, a chemoprevention researcher at M.D. Anderson Cancer Center in Houston, Texas, who has most recently worked on green tea.

Quercetin Vs. Prostate Cancer

There was an exciting presentation by Nianzeng Xing, MD, PhD, a research fellow in the Urology Department of the Mayo Clinic, Rochester, MN. He has been studying quercetin, a safe and abundant natural bioflavonoid. Since prostate cancer growth is fueled by androgens, researchers are interested in finding substances that can disarm these male sex hormones.

Dr. Xing's work is the first to demonstrate that quercetin has significant activity against androgen receptors. It caused dramatic reduction in the levels of two androgen-regulated tumor markers, including prostate-specific antigen (PSA). Dr. Xing suggested that quercetin could become a "chemopreventive and/or chemotherapeutic agent for prostate cancer." I thought his use of the term "chemotherapeutic agent" was daring, for it is rare for cancer researchers to suggest that nutritional agents could actually be used to treat existing disease.

A reporter immediately called out in alarm, "What's going to stop people from running out, buying quercetin and preventing all kinds of cancer?" What, indeed! In fact, prostate cancer patients needn't wait for official approval. It would be a good idea to step up one's consumption of foods that contain this nutrient, including apples, onions, green and black tea, leafy vegetables, beans, and red wine (presuming that alcohol does not aggravate one's prostate). Quercetin supplements are also available. It is uncertain what dose would be optimal for cancer patients. Some practitioners already recommend a preventative dose of 400 milligrams three times per day.

Inhibiting Telomerase

At the M.D. Anderson Cancer Center in Houston, Texas, Li Mao, MD is studying telomerase activity in the lung tissues of heavy smokers. Telomerase is an enzyme that conveys Methuselah-like longevity to cells that would otherwise have normal lifespans. It makes these cells virtually immortal and is an important part of the cancer process.

So how can one suppress telomerase? Retinoids, vitamin A-like compounds, significantly decreases the activity of telomerase. In a placebo-controlled trial, heavy smokers with no evidence of cancer were given a synthetic retinoid (called 4-HPR) to see if this would decrease telomerase activity. Such treatment significantly reduced expression of a biomarker for telomerase by more than 20 percent, indicating a reduced risk of lung cancer.

"This is the first data to provide promising evidence that a molecular biomarker may sensitively measure the efficacy of a chemopreventive agent in the lung," said the Houston scientist. It also inadvertently strengthens the rationale for using carrot juice as part of a holistic approach to cancer, an approach pioneered in the 1930s by the controversial Dr. Max Gerson. What goes around, comes around….

Novel Antitumor Agents

The poster sessions are to me the most fascinating part of AACR. They are a huge and changing bazaar of findings, where you also get to see the faces behind the research. The most interesting ones this year were devoted to novel antitumor agents, including:

1.  MGN-3, an anticancer agent made from rice bran and mushrooms
   
   
2.  SPES and PC SPES, two Chinese herbal mixtures used for pancreatic cancer
   
   
3.  EGCG, from green tea, used to treat pancreatic cancer cells
   
   
4.  Curcumin, derived from the spice turmeric, and resveratrol, derived from red wine
   
   
5.  Japanese butterfly alkaloids as a cytotoxic agent
   
   
6.  Butyric acid, derived from butter, used against leukemia cells
   
   
7.  Squalene, from shark liver oil, to protect bone marrow during chemotherapy
   
   
8.  Ascorbic acid and copper as a treatment for advanced breast cancer
   
   
9.  Anvirzel, extract of the oleander bush (Nerium oleander), as anticancer agent
   
   
10.  Morinda citrifolia (noni) against breast and colon cancer cells
    

Researchers also gathered four and five deep around posters devoted to dendritic cell vaccines…43 posters on a topic that is creating excitement in all parts of the cancer world. Yet none of the researchers I spoke to was familiar with the way that dendritic cell vaccines are currently being used at various unconventional clinics.

The fields of conventional research and CAM practice are groping towards each other but only connect at rare moments. Some conventional researchers scour the health food stores for new treatment ideas, but seem in the dark about how their research relates to the current practice of non-conventional medicine. As one example, the AACR researcher working on SPES and PC SPES had no idea what was in those two Chinese herbal mixtures! Conversely, alternative practitioners may consult the orthodox literature, but few of them thought it important to attend this meeting.

The challenge of the years ahead will be to knit together the best of conventional and alternative approaches into a new field, which has been called integrative oncology.

British Hospital Patients Also Suffer "Adverse Events"

It has previously been shown that a large number of American patients suffer "adverse events" when they enter conventional clinics and hospitals. But there was some doubt whether this was true in other countries as well. Now, a study of over 1,000 medical records from British hospitals shows that 11 percent of patients experienced an adverse event in British hospitals, over half of which were preventable. A third of these events led to disability or death.

The extrapolation of these data suggests that in England and Wales adverse events lead to an extra 3 million bed days in the hospital at a cost of at least one billion pounds per year, according to an article in the British Medical Journal {2001;322:517-9}.

"These results suggest that adverse events are a serious source of harm to patients and a large drain on NHS [National Health Service, ed.] resources," the authors wrote. Some are major events; others are frequent, minor events that go unnoticed in routine clinical care but together have massive economic consequences."

We frequently hear charges that alternative medicine is "dangerous" for patients. The claims are exaggerated, but should always be put into the context of what actually happens to patients when they take treatment in conventional hospitals, here and abroad.

More Praise for Vitamin C

Boosting your daily intake of fruit and vegetables could help protect you against cancer and heart disease, according to a new study from Cambridge University, England. Scientists there found that boosting vitamin C food intake cuts the risk of death from heart disease. Professor Kay-Tee Khaw studied 20,000 people aged between 45 and 79, and found that those with the highest vitamin C intakes had the lowest heart death rate. He concluded that an increase in the dietary intake of foods rich in ascorbic acid might have benefits in preventing both cancer and cardiovascular disease. Eating just 50 grams more fruits and vegetables per day (about two ounces) cuts the death rate by 20 percent, regardless of the person's age, blood pressure status or whether or not they smoked.

"Small and feasible changes within the normal population range of intake could have a large effect," Dr. Khaw said. A spokeswoman for the British Heart Foundation said the study confirmed the benefits of fruit and vegetables. She said: "This study contributes to a large body of research suggesting that vitamin C is cardioprotective." Even the National Cancer Institute suggests that people eat five portions of fruits and vegetables per day. I would add that these should be mainly fresh, organic and colorful produce. But also taking food supplements makes perfect sense as backup insurance.

Medicines from a Vacant Lot

While exotic plants from the Amazon are beautiful to look at, some of the most promising herbs for treating cancer have always been derived from common weeds. Weeds are defined as fast-growing plant species that thrive in areas that have been disturbed by human activities such as land clearing and trail making. Both the legendary Essiac and the Hoxsey formulas, as well as many other folk remedies, have relied on such common "nuisance plants" such as sheep sorrel, burdock, evening primrose, and red clover. If you look closely this summer, you'll probably find an alternative cornucopia growing on your lawn!

Now we are learning why weeds shine as medicines. John Stepp of the University of Georgia (Athens) and Daniel Moerman of the University of Michigan-Dearborn have studied medicinal plant use among residents in the Mexican highlands. These Highland Mayan Indians have lived in that same region in Chiapas, Mexico for millennia. Earlier research showed that they utilized about 600 plant species in their medicine. But the Mayan people don't cultivate medicinal plants, but gather them fresh when needed. The doctors worked for months in the rugged mountains of Chiapas to find where the plants they used were located.

In half a year, they observed these villagers collecting over 100 different plants for medicinal purposes. Fully a third of these turned out to be weeds. In fact, while weeds make up only 9.6 percent of North American plant species they constitute 25.8 percent of all Native American herbs.

Two obvious reasons for this are that weeds are abundant and are readily gathered in the fresh state. But Drs. Stepp and Moerman postulate that more subtle reasons are at work: weeds generally lack the physical protection provided to more settled plants by thick bark, woody stems, or thick leaves. They therefore have to rely on chemicals to poison or otherwise discourage predators {J Ethnopharmacol 2001;75:19-23}. These chemicals are what we humans then find useful in fighting infection, inflammation and even cancer. So weeds have real biological effects. "The reason for their use is that they are often efficacious," Stepp told the Lancet {2001;357:938}.

Overall, little research has been done on the potential medicinal value of common weeds. One reason is economic: weeds are readily available and their ingredients are well known chemicals in the public domain. On the other hand, chemicals from hitherto unknown Amazon plants could be patented and could make a fortune for its discoverers.

--Ralph W. Moss, Ph.D.