New Pancreatic Cancer Treatments

When TV actor Michael Landon died in 1991 of pancreatic cancer, the world became aware of this devastating disease, which strikes quickly and kills 95 percent of its victims, often within a few months after diagnosis. Pancreatic cancer has one of cancer's poorest survival rates because the pancreas itself traditionally has been a difficult organ for surgeons to reach, hidden as it is behind the stomach and liver.

Once there, surgeons must cope with the labyrinth of nerves and vessels that make up this vital organ of digestion. The pancreas secretes the hormone insulin, which enables the body to process carbohydrates.

Researchers at Roswell Park Cancer Institute in Buffalo, New York, are testing a promising new vaccine against pancreatic cancer, which is expected to strike 26,300 Americans this year. About 90 percent of pancreatic cancers have an abnormal variant of a gene called RAS, which results in an abnormal RAS protein.

The Roswell Park researchers worked with investigators from the National Cancer institute to design the study, basing their assumptions on preclinical evidence that a special vaccine against this mutant RAS protein could effectively "jump-start" a weakened immune system to fight the disease.

Applying techniques of molecular biology, the researchers sequence each patient's abnormal RAS gene to identify the specific mutation. A vaccine is then prepared that mimics a section of the individual's specific mutated RAS protein.

Professionals can then administer monthly boosters of the vaccine to generate an immune response against mutant RAS protein. An immune response is the ability of certain blood cells (lymphocytes) and their products (antibodies) to attack tumor cells. Because only the cancer cells have mutant RAS, a therapy tailor-made against the target will, in theory, selectively spare normal tissue from the assault.

"Gene-directed therapy represents an important new avenue in pancreatic cancer research," said Dr. Neal J. Meropol, a clinician in Roswell Park's division of medicine and the study's principal investigator.

"If successful, this study and others like it may lead to a time when physicians can confidently inform their patients that a pancreatic cancer diagnosis is not a death sentence and that more effective treatments are available."

Recently, researchers at the Stehlin Foundation for Cancer Research in Houston announced impressive results treating pancreatic cancer with 9-Nitro Camptothecin (9NC), made from the Chinese Camptotheca acuminata tree.

In Japan several years ago, scientists discovered that compounds from this tree were effective against a number of cancer tumors. Preliminary results indicated that 9NC, when taken in capsule form, improved survival rates with fewer debilitating side effects than many traditional treatments.

"We look to camptothecin derivatives to one day become 'the poor man's cancer treatment,'" said foundation founder Dr. John S. Stehlin, Jr. "The patient can take this medication at home and avoid the inconvenience of having to receive drugs intravenously at the hospital."

Last updated Jan 2/07