New approach to fight treatment-resistant colon cancer

Washington, Dec 9 (ANI): A research team led by an Indian-origin scientist has revealed that adding a small molecule to the cancer drug Temozolomide effectively treats colon cancer cells that are highly resistant to treatment.

Lead researcher Satya Narayan has found that addition of a small molecule to the cancer drug disrupts repair mechanisms in tumour cells.

"This is very important because aside from aggressive surgery with possibly chemotherapy, there are no specific treatments for colon cancer," said Narayan, a professor of anatomy and cell biology at the College of Medicine and a member of the UF Shands Cancer Centre.

"The recurrence rate for this type of cancer after surgery is very high, about 30 to 50 percent, and there is an urgent need to develop new approaches to manage this deadly disease," Narayan added.

The research team evaluated more than 140,000 small molecules, when they finally arrived at a tiny molecule that precisely blocks the ability of cancer cells to recognize and repair the DNA damage inflicted by Temozolomide, or TMZ.

"Our idea was if you induce DNA damage (with TMZ), and at the same time block cell repair, you can synergize toxic effects to the cancer cells," Narayan said.

"We hope that with this combination treatment we can reduce the tumours drastically and expand the lifetime of patients much longer than is currently possible," Narayan added.

By combining TMZ with the small molecule, researchers were able to disable the colon cancer's ability to manufacture repair enzymes.

The University of Florida researchers effectively used an amount of TMZ that is about 10 times lower than recommended in its studies of mice with human colon cancer tumours.

If only about one-tenth as much TMZ is needed to kill cancer cells, Narayan said, it will be possible to use lower doses of a drug that creates a great deal of adverse side effects, a partial listing of which includes anxiety, back pain, breast pain, constipation, cough, diarrhea, dizziness, drowsiness, dry skin, hair loss, headache, joint pain, loss of appetite, mouth sores, muscle aches and nausea.

The study appears in Molecular Cancer Research, a journal of the American Association for Cancer Research. (ANI)