'U' Researchers Use Modified Salmonella To Combat Cancer
MINNEAPOLIS (WCCO) -- In the kitchen, Salmonella can cause food poisoning. However, in the fight against cancer, it may become a powerful weapon.
Over the past five years, University of Minnesota cancer researcher Dr. Edward Greeno has treated thousands of cancerous mice with salmonella.
Greeno, who is the Medical Director at the University's Masonic Cancer Clinic, said the response depended on the type of cancer and the specific experiment.
"But, in general terms, we've reduced the volume of tumor in the liver by about s half to three quarters with a single treatment of the Salmonella," said Greeno.
Fred Oakden of Otsego is one of the first humans to receive the special Salmonella therapy. He remembers the day six years ago when his continual fatigue was diagnosed as colon cancer.
"I had a 2-inch tumor on my colon," said Oakden. "I had several large spots and a tumor on my liver."
He and his wife of 48 years, Margaret, agree it has been a valiant battle through surgery and multiple rounds of chemotherapy. But, but the standard treatment options have been exhausted. The clinical trial offered some hope. Oakden described the therapy as drinking a single plastic shot glass of liquid. There were none of the harsh side effects associated with the chemotherapy he had endured.
The salmonella bacteria are not the basic strain associated with food poisoning. Greeno's Medical School colleague, Dan Saltzman, M.D., Ph.D., genetically modified the salmonella in two ways; to weaken it and to carry Interlueken 2.
"Interlueken 2 is one of the master regulators for the immune system. It's one of the things your body normally makes when you have a bad infection," Greeno said. "It stimulates T-cells, parts of the immune system that are good for attacking other cells, one of the cell types that we think are important for killing cancer cells."
Greeno added that Salmonella behaves ideally for the fight against certain cancers.
"Salmonella likes to get inside of cells," said Greeno. "It's nice for targeting something like colon cancer because it naturally goes to the gut, to lymph cells, to liver cells, all the places colon cancer would normally (spread)."
Dr. Greeno said it took five years to get FDA approval to conduct this first round of clinical trials on humans. The Phase I stage of testing should conclude in three to six months and involve 18 to 24 patients. Wider, Phase II clinical trials should begin later this year. Greeno cannot help being hopeful, but cautions against drawing premature conclusions.
"Certainly (it has been) a great treatment for mice with cancer," he said. "Hopefully, it will turn out to be a great treatment for humans with cancer."
