A Common Bacteria Can Be Injected Directly Into Tumors to Fight Cancer
is at best benign (it lives in the soil) and at worst harmful (it can cause infections). But a slightly modified version of the bacterium could be a completely new treatment for
published this week in
The team, led by researchers at the Johns Hopkins Sidney Kimmel Comprehensive Cancer Center, first tested C. novyi in rats where they had induced tumors. The bacteria make enzymes that broke through cell wells, then gobble up the proteins spilled by the cancerous cells. The rat studies showed promise, so the researchers then injected the bacterium into the naturally occurring tumors of 16 dogs whose owners had given permission. After the injection, the tumors disappeared in three of the dogs and shrank by at least 30 percent in three others. The dogs showed signs of bacterial infection-fever, inflammation, abscesses-but the side effects were no worse than what we already tolerate in cancer treatments.
Then the researchers tested the treatment in a human patient. A 53-year-old woman whose retroperitoneal leiomyosarcoma-a rare smooth muscle tumor-had spread to her liver, lungs, abdomen, upper arm, and shoulder had 10,000 spores of C. novyi injected only into the tumor in her shoulder. That tumor shrank; the others did not. More human trials are currently underway.
It's just one study so far, but this study is promising evidence that bacteria therapy for cancer could work. There idea has been studied for decades now, but
other bacteria such as
used to treat cancer were too dangerous and inconsistent in their effectiveness.
seems to be an improvement. Doctors have also experimented with using viruses like
measles to attack tumors
Bacteria and viruses that make us sick, after all, are already exquisitely engineered to attack our cells-we just need to prompt them to attack the right ones. [ Science Translational Medicine ]
Top image: Rod-shaped C. novyi (dark purple) germinating in a dog tumor. David L. Huso and Baktiar Karim of the Johns Hopkins Department of Pathology .