It's in this rough-and-tumble environment, controlled by a dizzying array of molecular signals, that researchers at the James P. Wilmot Cancer Center are grappling with a conundrum: Starve a tumor of oxygen, and the tumor should die but without oxygen, pretty much all of today's anti-cancer weapons are useless. Feeding the tumor may actually be better for the patient.
"It's like a two-headed beast," says Edith Lord, Ph.D., professor of Oncology in Microbiology & Immunology at the University of Rochester's cancer center. "If you cut off the blood vessels, the tumor doesn't grow, but it's also harder to treat with current therapies."
Five years ago the dawn of a new era in cancer research the pursuit of anti-angiogenesis, or the cutting off or prevention of blood vessel growth was hailed as a new way to knock out tumors by starving them of oxygen. But progress has been slow and spotty, and scientific results inconsistent. There have been a few clinical trials of the new medicines, but none is yet approved for widespread use.
Now doctors are coming more to terms with the negative complications of starving tumors of oxygen.
"The crucial role that oxygen plays in killing tumors has been under appreciated," says Bruce Fenton, Ph.D., associate professor of radiation oncology at the Wilmot Cancer Center.
Radiation and other current therapies rely on the formation of harmful molecules known as free radicals to damage cells, but without oxygen their efforts fall short as cells can often repair themselves. Cancer cells that contain oxygen are about two to three times more vulnerable to radiation than cells without, says Fenton.