The pathophysiology of cancer involves uncontrolled cellular proliferation–that we know–but the process doesn’t go on forever. After reaching a certain size, tumors do stop growing. This phenomenon is probably driven by growth-inhibiting chemicals that are released by tumor cells themselves.

Scientists are now trying to harness this phenomenon using a decidedly counterintuitive strategy: introducing cancer cells into the bodies of mammals–including humans–that are already afflicted with cancer. The strategy amounts to fighting cancer with cancer. Remarkably, early results from studies of the technique have been positive.

The technique was developed by Barry Smith and colleagues at the Rogosin Institute, an independent treatment and research center in New York. Smith’s group creates pea-sized beads of mouse kidney cancer cells that are encapsulated in a growth-restricting shell.

Initially, the beads contain about 150,000 cancer cells. During an incubation period however, all but 1% of those cells die, according to Smith. The remaining ones secrete proteins or peptides that inhibit tumor growth. Some of the chemicals promote cell death directly; others impair a cell’s ability to stimulate new blood vessel formation which is  needed for cellular survival.

“They reach a stable state in which there is cell division and cell death,” Smith said in an interview. “They are producing inhibitory factors that regulate their growth.”

Once the encapsulated concoction is “mature” in this way, Smith’s group  implants the beads into the abdominal cavities of cancer patients.

In a pair of studies released last week in Cancer Research, Smith’s group reported that their treatment reduced tumor size in laboratory mice, dogs and cats. Many cancer-stricken animals survived longer than expected. (more…)

Scientists at the Medical College of Georgia have figured out why a high-fiber diet helps prevent and possibly treat colon cancer.

Apparently, the stuff activates a cellular receptor that triggers a biochemical cascade which leads to apoptosis, or cell death in malignant cells.

In a fiber-poor environment, colon cancer cells deactivate the receptor, which is called GPR109A, by methylating the gene responsible for its production.

DNA methylation inhibitors are being studied as treatments for several cancers right now.

“We know the receptor is silenced in cancer but it’s not like the gene goes away,” Vadivel Ganapathy explained to BurrillReport.  He’s the senior author on the paper, which appears in Cancer Research.

The beneficial events begin when gut bacteria metabolize fiber using a process that releases butyrate. This chemical binds to the receptor and the next thing you know, cancer cells vaporize. 

But that’s not all. Activation of this receptor may also reduce inflammation which can promote cancer formation.

And wait, there’s more. Butyrate seems able to inhibit an enzyme that promotes uncontrolled growth of malignant cells.

Straight butyrate might work even better than fiber, but the stuff has an ungodly taste. And since fiber tastes like, well, fiber, the MCG scientists wonder whether a related compound like niacin, also known as Vitamin B3 or nicotinic acid, could have similar benefits.

Many people take niacin to control hypercholesterolemia.

That’s a lot of biochemistry but in a nutshell, “colon cancer does not want to have anything to do with butyrate,” summarized Ganapathy.