University of Waterloo Team Develops Novel Bacterial Cancer Treatment

A research team led by the University of Waterloo is developing a novel method for cancer treatment. This approach involves engineering bacteria to specifically target and consume tumour cells internally.

This method involves engineering bacteria to specifically target and consume tumour cells internally.

The Treatment Mechanism: Harnessing Nature's Clean-Up Crew

The approach utilizes Clostridium sporogenes, a bacterium naturally found in soil. This organism thrives in environments completely devoid of oxygen. The core of solid cancerous tumours, which consists of dead cells and lacks oxygen, provides an ideal environment for this bacterium to multiply and consume nutrients, thereby contributing to the reduction of the tumour.

Overcoming Limitations: Engineering for Enhanced Survival

A key challenge identified is that as the bacteria reach the outer edges of tumours, they are exposed to low levels of oxygen and subsequently die, preventing complete tumour destruction.

A key challenge identified is that as the bacteria reach the outer edges of tumours, they are exposed to low levels of oxygen and subsequently die, preventing complete tumour destruction.

To overcome this, researchers introduced a gene from a related bacterium into Clostridium sporogenes to enhance its oxygen tolerance.

Precision Control: The Quorum-Sensing Switch

To prevent the engineered bacteria from inadvertently growing in oxygen-rich areas, such as the bloodstream, a quorum-sensing mechanism was developed. This system ensures that the oxygen-resistant gene is activated only when a sufficient concentration of bacteria is present, typically indicating their presence within a tumour.

This system ensures that the oxygen-resistant gene is activated only when a sufficient concentration of bacteria is present, typically indicating their presence within a tumour.

This activation occurs via chemical signals released by the bacteria themselves, ensuring the gene is not turned on prematurely.

Research Milestones and Future Outlook

Researchers successfully demonstrated that Clostridium sporogenes can be modified to tolerate oxygen.
A subsequent study confirmed the functionality of their quorum-sensing system through the production of a green fluorescent protein.

The next step for the research team is to integrate both the oxygen-resistant gene and the quorum-sensing timing mechanism into a single bacterium for testing in pre-clinical trials.

The Team Behind the Innovation

The project originated from the work of PhD student Bahram Zargar and involved faculty members Dr. Marc Aucoin, Dr. Brian Ingalls, and Dr. Pu Chen from the University of Waterloo. The research team partnered with CREM Co Labs, a Toronto-based company, on this initiative.