Scientists Genetically Engineer Human Cells to Fight Cancer

Aug. 31, 2006 — -- Seven years ago, Mark Origer was diagnosed with a malignant melanoma, a sometimes curable skin cancer that can be deadly if it spreads to other parts of the body.

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By 2004, his cancer had spread to his liver, lung and lymph nodes.

Origer, 53, was optimistic about a cure, but conventional treatments failed him.

"I was hopeful every time I tried a new treatment. I hoped it would be the end of my disease," Origer said.

But nothing worked.

"It felt defeating," he said.

Desperate for a cure, Origer enrolled in a clinical trial at the National Cancer Institute in Bethesda, Md. The trial tested a very experimental therapy that had never before been used in people.

What attracted Origer, of Waterville, Wis., to the cancer institute was a unique process where genetic engineering is applied to humans.

The process is usually associated with hybrid animals and super foods, but is being tested to fight diseases in people.

The cancer institute's researchers are using genetically engineered immune cells to shrink tumors in cancer patients like Origer.

"This is the first gene therapy for cancer. … That is why it is so important," said Dr. Steven A. Rosenberg, who headed the trial as chief of surgery at the National Cancer Institute.

Researchers took immune system cells from the blood of 17 advanced melanoma patients who, like Origer, had not been helped by conventional treatments. Origer had only three months to four months left to live when the experimental treatment began.

These ordinary blood cells, called T cells, were genetically engineered to become cancer-fighting cells that could recognize and attack the life-threatening melanoma.

The cancer-fighting cells were then injected back into each patient. Researchers hoped that the new T cells would multiply and fight off the cancers.

The experimental therapy could be a major medical and scientific advance.