25/09/2000 09:44:38
Según un estudio del Imperial College and Hammersmith Hospital de Londres
Un equipo de científicos del Imperial College and Hammersmith Hospital de Londres ha demostrado un mecanismo de acción por el que Aspirina podría detener el avance del cáncer de próstata, el tipo de cáncer más común en los hombres y el segundo más mortal del mundo.
Según han observado, el fármaco actúa deteniendo la función de una enzima que estimula el crecimiento del tumor y frenando así su avance.
Los científicos del Imperial College and Hammersmith Hospital han estudiado un centenar de muestras de tejido canceroso prostático.
Ello les ha permitido descubrir una presencia de niveles inusualmente altos de una sustancia química, cox-II, en una proporción cuatro veces superior a lo normal, en las células cancerosas.
Esta sustancia actúa estimulando la proliferación de las células cancerígenas. Aspirina, al inhibir la acción de la cox-II, podría frenar el desarrollo del cáncer de próstata.
Debido a que la enfermedad suele afectar a personas de avanzada edad, un control efectivo a largo plazo del crecimiento del tumor podría ser un tratamiento más adecuado, según los científicos, que la cirugía o la radioterapia, más agresivas.
Cada año son diagnosticados más de 16.000 casos de cáncer de próstata, y de ellos sólo 4 de cada 10 sobreviven al cabo de cinco años.
04:59 PM ET 03/16/00 Committee Recommends Cancer Drug WASHINGTON (AP) _ A Food and Drug Administration advisory panel is recommending approval of a drug to be added to first-line treatment for widespread colorectal cancer.
The Oncologic Drug Advisory Committee on Thursday recommended approval for Camptosar injection, made by Pharmacia & Upjohn, in combination with other drugs as a first treatment for patients with colon and rectal cancer.
The FDA is not bound by advisory committee recommendations but usually follows them. Camptosar won FDA approval as a follow-up cancer treatment in 1996.
The committee unanimously recommended the earlier use following reports from clinical trials in which patients who received the drug showed delayed tumor progression and lived longer than those without it.
The drug would be used in combination with two other drugs, fluorouracil and leucovorin. Side effects associated with the drug in clinical trials included diarrhea, nausea and vomiting.
Researchers Say Herbal Formula Offers Relief From Chemotherapy Ills June 16, 2000
COLUMBUS, Ohio (AP) - Cancer patients can significantly and safely reduce the side effects of chemotherapy by taking an herbal formula called Amrit, according to research conducted on the ancient Indian medicine.
"It makes chemotherapy more bearable for patients without interfering in the cancer treatment," said Dr. Hari Sharma, a professor emeritus and former director of cancer prevention and natural products research at Ohio State University.
He and researchers at the All India Institute of Medical Sciences in New Delhi recently completed a study on Amrit and plan to present their findings at the St. Joseph Hospital's Center for Healthy Aging in Chicago on Saturday.
Patients reported Amrit improved their overall well-being during chemotherapy by reducing instances of nausea, vomiting, diarrhea, insomnia, anorexia, and boosting their energy levels.
Several similar drugs are available that - unlike Amrit - have gone through controlled clinical trials and have been approved by the U.S. Food and Drug Administration, said American Cancer Society spokeswoman Joann Schellenbach.
However, she said, any research that can further the understanding of using herbs to treat ailments is encouraged.
"This may be something that proves to be helpful, but with any new substance, we just don't know this early on," she said.
While Amrit has been used for many generations in India as an antidote for healthy aging, little research exists on its medicinal qualities. Sharma acknowledged that the formula has undergone only a few controlled studies and those have been performed over the last 10 years.
Amrit is an antioxidant that contains 44 herbs and minerals, including large amounts of vitamins C and E, as well as beta carotene. Sold by Maharishi Aayurveda Products International, in Colorado Springs, Co., it comes in tablet and paste forms.
Taken together, the herbs increase a chemical in the liver that is responsible for cleansing from the body toxins that cause the side effects, Sharma said.
Dr. Christine Horner-Taylor, a plastic surgeon specializing in breast reconstruction for cancer patients, routinely recommends Amrit to her patients after one had "miraculous" results.
During one round of chemotherapy, Horner-Taylor's patient became incredibly ill, was unable to eat and had no energy. She took Amrit during subsequent rounds and had no side effects.
"She looked just radiant. Most of the time, they look ashen and meek after chemotherapy, but she just was glowing. I had never seen anything like that before," said Horner-Taylor, whose practice is in Edgewood, Ky., across the Ohio River from Cincinnati.
Unfortunately, Horner-Taylor said, many cancer patients don't use Amrit and they remain uncomfortable throughout chemotherapy because most doctors are leery about alternative medicine.
But she said she hopes research like Sharma's will give doctors the proof they need that herbs can work to treat ailm
Researchers Find Cancer-Fighting Chemical In Hazelnuts March 29, 2000
SAN FRANCISCO (AP) - Researchers say they've found the active ingredient of Taxol in hazelnuts, a discovery that could lead to new ways to make the cancer-fighting drug.
"This is potentially good news for cancer patients," said Angela Hoffman, a member of the research team at the University of Portland in Oregon, who was to present the study Wednesday at the national meeting of the American Chemical Society.
The finding may be of interest to competitors of Bristol-Myers Squibb, which holds the exclusive license to make Taxol. Worldwide sales of Taxol brought the company $ 1.5 billion last year, 7.3 percent of its total sales. The drug is now made using chemicals from yew tree needles.
One thing is clear: Eating hazelnuts has no cancer-prevention or cancer-fighting benefits.
"Won't do any good at all, because Taxol is not active orally," said Robert Holton, a Florida State University chemist who gets royalties from Bristol-Myers for the method he developed of synthesizing the drug.
However, having a new source of the active ingredient, paclitaxel, is compelling, said Steve Tighe, senior pharmaceutical analyst at Merrill Lynch. He said much more information is needed before anyone can say if it can be used against cancer.
It took nearly 30 years after paclitaxel was found in yew trees to get Taxol on the market. The latest discovery is still in the lab.
Many questions remain unanswered. Is it economical or even possible to extract paclitaxel from hazelnuts commercially? Will regulators approve it? How many companies would get the license to do it?
Gram for gram, hazelnuts carry just one-tenth of the chemical that yew trees do, researchers said.
"I'm not sure I see what the advantage of the hazelnut over the yew tree would be," said oncologist Clifford Hudis, chief of the Breast Cancer Medicine Service at Memorial Sloan-Kettering Cancer Center.
Taxol and the yew needles used to make it are not in short supply.
Controversy surrounded the drug when the Food and Drug Administration first approved it in late 1992 because Pacific yew trees, its only known source, were being cut down to make it.
But Bristol-Myers quickly found a synthetic production method that starts with the needles of European and Asian yews. No trees die and the needles are plentiful. "By the gazillions, and they grow back," said Holton.
The Oregon researchers found paclitaxel in hazelnut trees while looking for a compound that makes some trees resistant to a fatal plant disease called Eastern Filbert Blight. They isolated the chemical from nuts, branches and shells.
Bristol-Myers goes to trial in May in New Jersey to defend its patent against nine pharmaceutical companies seeking to market generic versions of Taxol. The company did not return calls requesting comment Tuesday.
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