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Bacteria In Tumors Can Inactivate Common Chemotherapy Drugs, Study Suggests (arstechnica.com)
Researchers caught the bacteria Mycoplasma hyorhinis hiding out among cancer cells, thwarting chemotherapy drugs intended to treat the tumors they reside in. The findings have been published this week in Science. Ars Technica reports: Drug resistance among cancers is a "foremost challenge," according to the study's authors, led by Ravid Straussman at the Weizmann Institute of Science. Yet the new data suggest that certain types of drug-resistant cancers could be defeated with a simple dollop of antibiotics alongside a chemotherapy regimen. Dr. Straussman and his colleagues got a hunch to look for the bacteria after noticing that, when they grew certain types of human cancer cells together in lab, the cells all became more resistant to a chemotherapy drug called gemcitabine. This is a drug used to treat pancreatic, lung, breast, and bladder cancers and is often sold under the brand name Gemzar. The researchers suspected that some of the cells may secrete a drug-busting molecule. So they tried filtering the cell cultures to see if they could catch it. Instead, they found that the cell cultures lost their resistance after their liquid broth passed through a pretty large filter -- 0.45 micrometers. This would catch large particles -- like bacteria -- but not small molecules, as the researchers were expecting.
Looking closer, the researchers noticed that some of their cancer cells were contaminated with M. hyorhinis. And these bacteria could metabolize gemcitabine, rendering the drug useless. When the researchers transplanted treatable cancer cells into the flanks of mice -- some with and some without M. hyorhinis -- the bacteria-toting tumors were resistant to gemcitabine treatment.
Looking closer, the researchers noticed that some of their cancer cells were contaminated with M. hyorhinis. And these bacteria could metabolize gemcitabine, rendering the drug useless. When the researchers transplanted treatable cancer cells into the flanks of mice -- some with and some without M. hyorhinis -- the bacteria-toting tumors were resistant to gemcitabine treatment.
Really get someone with proper English language skills to proof read these crap headlines at least. I know the text beneath it is obviously too much, but at least fix the titles.
The wiki page on how gemcitabine works is pretty fascinating. The drug as administered doesn't kill cells. It gets modified by enzymes in the cell into a form which interferes with DNA replication and blocks DNA repair. That's what kills the cell.
Presumably the bacteria are just metabolizing it before these enzymes can convert it into its toxic form (or lack one of the needed enzymes). So no, not a superbug which digests a toxic material.