Scientists at Brigham and Women’s Hospital (BWH) have found a way to fight cancer with cancer. The team genetically engineered cancer cells to release anti-cancer drugs at the site of established tumors, as well as stimulating the immune system against the disease. Tests in mice proved promising as both a therapy and a preventative vaccine.
Cancer vaccines are an emerging area of research, where patients are often administered inactive tumor cells or proteins expressed at high levels by cancer cells. This trains the immune system to recognize existing tumors and mount an assault on them, and can prevent the spread or appearance of new tumors.
For the new study, the BWH team took a new approach, using living tumor cells instead. While it sounds like a bad idea to give cancer patients more cancer, these cells were engineered using CRISPR to become double agents. Cancer cells can travel long distances to return to the site of established tumors, and once there the engineered cells will unleash a payload of anti-cancer drugs and factors that alert the immune system to clear them out.
“Our team has pursued a simple idea: to take cancer cells and transform them into cancer killers and vaccines,” said Khalid Shah, corresponding author of the study. “Using gene engineering, we are repurposing cancer cells to develop a therapeutic that kills tumor cells and stimulates the immune system to both destroy primary tumors and prevent cancer.”
These therapeutic tumor cells (ThTCs) were tested in mice with advanced glioblastoma, and were found to eliminate the tumors in many of the animals, significantly increasing survival rates and providing long-term immunity against recurrent and metastatic cancer. The technique also appeared to be safe, thanks to a kill-switch that can be activated if needed to eradicate the ThTCs.
As promising as the results may be, the usual caveats apply – especially that animal studies don’t always translate to humans. The team plans to continue investigating ThTCs, including how they might be used in humans and how well they might work against other cancer types.
The research was published in the journal Science Translational Medicine.
Source; Brigham and Women’s Hospital