Scientists Engineer Bacteria to ‘Eat’ Tumors From the Inside Out

In a groundbreaking development in cancer treatment, researchers are engineering bacteria to target and destroy tumors from within. This innovative approach, likened to the classic arcade game Pac-Man, utilizes genetically modified bacteria to infiltrate tumors and consume cancer cells, offering a potentially new way to combat the disease.

How It Works: Targeting Tumors with Clostridium sporogenes

The research centers around Clostridium sporogenes, a bacterium commonly found in soil that thrives in oxygen-free environments. The inner core of solid tumors, often lacking oxygen, provides an ideal breeding ground for this microbe. “Bacteria spores enter the tumor, finding an environment where there are lots of nutrients and no oxygen, which this organism prefers, and so it starts eating those nutrients and growing in size,” explained Dr. Marc Aucoin, a chemical engineering professor at the University of Waterloo . “So, we are now colonizing that central space, and the bacterium is essentially ridding the body of the tumor.”

Overcoming the Oxygen Barrier

A significant challenge in this approach is the bacteria’s inability to survive in oxygen-rich environments found at the tumor’s edges. To address this, researchers introduced a gene from C. Aminovalericum, a related bacteria known for its oxygen tolerance, into C. Sporogenes. This modification allows the bacteria to survive longer in the outer areas of the tumor .

Quorum Sensing: Ensuring Safety and Control

To ensure the treatment remains localized and safe, the team employed a technique called quorum sensing. This natural bacterial communication system allows bacteria to estimate their population size and regulate their activity accordingly. By integrating quorum sensing into C. Sporogenes, researchers can control when the bacteria become fully active, ensuring they stop growing once the tumor is eliminated and don’t spread to healthy tissues .

Future Directions and Preclinical Trials

The research, published in the journal ACS Synthetic Biology, represents a major step forward in cancer treatment. Researchers are now working to combine the quorum sensing system with the genetic modification for oxygen tolerance, aiming to create a self-regulating system that halts bacterial growth upon tumor elimination. This involves creating “biocircuits” using DNA to precisely guide the bacteria’s activity . The next step is to move into preclinical trials to assess the safety and efficacy of this innovative cancer therapy .

Key Takeaways

• Researchers are using genetically engineered Clostridium sporogenes bacteria to consume tumors from the inside out.
• A gene from C. Aminovalericum was added to enhance the bacteria’s oxygen tolerance.
• Quorum sensing is used to control bacterial growth and ensure treatment safety.
• The research is a promising step towards a new, targeted cancer therapy.