Spores of the Clostridium sporogenes bacterium have shown promise in delivering cancer drugs into tumors. By being able to grow in soil without oxygen, this bacterium can grow within tumors. Thus UK and Dutch scientists have genetically modified an enzyme into the bacterium to activate a cancer drug.
The researchers have proven that the spores can only grow inside solid tumors, including breast, brain, and prostate cancer tumors, but not in body tissues where oxygen is present.
Other researchers have investigated Clostridium vectors to potentially deliver cancer drugs, but these researchers have improved a version of the enzyme into the bacterium.
In animal models, the drug was injected into the bloodstream and became activated when it was triggered by the enzyme. When the enzyme is activated, it is in the vicinity of the solid tumor cells and destroys them.
This technique is a natural phenomenon and offers a specific target of killing tumor cells and leaving the healthy cells untouched. This observation represents overcoming a key obstacle in cancer therapy. It can be produced at greater quantities in the tumor than before and is more efficient at converting the dormant drug into its active form for destroying cancer cells.
Patient trials are planned to start in 2013.
The latest progress will be presented this Fall at the Society for General Microbiology conference at the University of York.
