According to a report on the Houston Chronicle website, cancer researchers are trying to exploit this capability of cells in treating various cancers that otherwise survives the harsh chemotherapy treatments.
The experiments are based on the fact that starving cells start eating their less-used components in order to survive the scarce food conditions and continue doing so until they found another reliable source of energy.
In their experiments, scientists have already succeeded in eliminating tumors by inducing the cancerous cells to undergo continual cannibalism. However, some experiments show that cancer cells actually use the process to survive the deprivation of nutrients.
"There are still more questions than answers," said Dr. Seiji Kondo, associate professor in the Department of Neurosurgery at the University of Texas M.D. Anderson Cancer Center, who, until recently was one of a handful of academics studying the link between autophagy and cancer.
The research in the area has been triggered by understanding the fact that certain types of cancers use autophagy to survive the harsh conditions of chemotherapy. This made researchers to look for the drugs that could inhibit autophagy, and use such drugs along with the chemotherapy ones.
Kondo said his group has had some success inhibiting autophagy in brain cancer patients being treated with the chemotherapy drug Temodar. However, Kondo also wants to exploit this self-killing potential of cells.
Until recently, cancer scientists believed that most therapies killed cancer by inducing apoptosis, or programmed cell death. But now, Kondo said, researchers have started realizing that some of these drugs, such as Tamoxifen and rapamycin, may trigger autophagy. In such cases, scientists might seek to supplement chemical treatments for cancer by removing limits on autophagy within the body.
"If we understand the mechanisms by which radiation and chemotherapy fail to induce apoptosis or autophagy in some tumor cells, we could design drugs that would work in combination with radiation therapy or chemotherapy to cause the tumor cells to die by apoptosis or autophagy," said Dr. Gordon Mills, chairman of M.D. Anderson's Department of Molecular Therapeutics.
The recipe behind the augmented treatment is to identify when to stimulate autophagy and when to inhibit it, thus, depriving cancer cells of the ability to survive the harsh conditions imposed by chemotherapy.
Increasing efforts to answer these difficult questions, Kondo said, explains the rapid growth in the field of autophagy.
"We still have a lot of work to do," he said.
