A Rice University chemist’s research conduct years ago to protect people from radiation poisoning due to nuclear fallout may now offer a glimmer of hope to patients with pancreatic cancer. Researchers at the University of Texas MD Anderson Cancer Center and Rice University have published a study on the novel use of amifostine; so an approve intravenous drug used to protect healthy tissue in patients undergoing radiation therapy.
The results of new research led by MD Anderson radiation oncologist Dr. Cullen Taniguchi appear in an open-access paper in Nature’s Scientific Reports and are detail in a report on MD Anderson’s Cancer Frontline blog. Until now, if doctors use levels of radiation sufficient to destroy most tumors in the head of the pancreas; so the radiation would also destroy the duodenum, which is the first stage of the small intestines.
But data from decade-old research by Rice University chemist James Tour suggest there might be another way. Tour, working at the time on a federal Defense Advance Research Projects Agency grant; so was looking for a nanoparticle enable method to curtail radiation poisoning in people expose to nuclear fallout. Tests on an animal control group given amifostine orally proved far more interesting.
Amifostine develop at Walter Reed Medical Center in the 1970s and was identified as a radio protectant,” Tour said. “It is use intravenously to this day to protect patients. Working with Kathryn Mason, a now retired faculty member at MD Anderson, Tour and his Rice group were testing antioxidant nanoparticles; which is know as PEG-HCCs for their ability to quench the effects of radiation. Federal funding stop at the end of the George W. Bush administration in 2008, they said.
But Mason remembered. A few years later, they recommend that Taniguchi; hence a new recruit to MD Anderson; so view the old data and visit Tour. Taniguchi, a radiation oncologist at MD Anderson and leader of the new study; so immediately saw the potential for treating pancreatic cancer. Intravenous amifostine can cause severe nausea and hypotension; so greatly limiting its use for patients, Taniguchi said.
Protection to more patients
An effective oral version with less harmful side effects would allow us to extend this protection to more patients. When you get a tumor in the head of the pancreas, you can’t do surgery; so because the pancreas wraps around a huge artery, Tour said. You can’t do radiation because if you blast the tumor with the levels you’d need to kill it; so you’d destroy the duodenum that connects the stomach to the small intestine. The duodenum contains groups of stem cells in a structure called a crypt.
The crypts produce epithelial cells to replace those worn away by food that passes through the intestine. These crypts are the first thing to go when they’re expose to radiation,” Tour said. “When they’re gone, bacteria on the food causes gastrointestinal syndrome. As it happens, amifostine taken orally is broken down by the enzymes in the duodenum.
When the drug passes through the duodenum and jejunum; so the alkaline environment there translates it into another drug, radio-protective WR-1065; hence precisely where it need most. Ideally, a patient who takes amifostine a short time before radiation could better withstand a high-enough dose need to eradicate the tumor, Tour said. Even though amifostine is approve by the Food and Drug Administration; so Tour warn that using it as part of a new strategy to treat pancreatic cancer is likely years away.