Tuberculosis Vaccine Shrinks Liver Tumors, Improves Survival Time in Mouse Study
Michelle Milliken
The Bacillus Calmette-Guérin vaccine (BCG), derived from the live bacteria Mycobacterium bovis, is used for protection against tuberculosis. However, it’s also known to have immune-boosting properties and has been approved for use against bladder cancer. New research has found that it may also be helpful for another type of cancer.
Researchers at University of California Davis recently investigated how well BCG works against the most common form of liver cancer, hepatocellular carcinoma. The team gave a single dose to mice with these tumors, and afterward, the tumors shrank and survival times were found to increase in both male and female mice. The researchers believe this may be a promising treatment for the disease, which they say is the third leading cause of cancer-related deaths globally.
Yu-Jui Yvonne Wan, senior author and vice chair for research in the UC Davis Department of Pathology and Laboratory Medicine, says, “HCC is very difficult to treat. This cancer is considered a cold tumor, which does not respond well to immunotherapy. We had a good reason to believe that the BCG vaccine could stimulate an immune response…
"Our study showed that BCG immunotherapy for HCC is different from and superior to other immunotherapies. It requires only a single injection. In animal models, BCG generated better anti-liver cancer treatment outcomes than other standard immunotherapies, such as anti-PD-1. This means a potentially more simplified treatment plan.”
In their study, published in Advanced Science, the team also found that mice treated with BCG had reduced lipid levels, improved liver metabolism, reduced scarring, and more T cell and white blood cell infiltration into the tumor. However, blocking T cells was found to reverse these effects.
With BCG’s safety and apparent impacts on scarring, metabolism, and the immune system, the team says it could be beneficial for a disease whose other treatments include surgery, radiation, chemo, immunotherapy, and liver transplant.
Going forward, the researchers hope to investigate whether more doses or differently timed doses could be more effective, as well as whether it could work for other forms of cancer.
Wan says, “If BCG treated a tough tumor like liver cancer, I'm optimistic it can work well on other hard-to-treat cancers. We would need more research to move to the next step. For example, we don't know how long this immune memory lasts, so efficacy of this vaccine over time is still a mystery. The mechanism can be complicated, and further research is needed.”
You can read the whole study here.
