mRNA Vaccine to Prevent Colorectal Cancer Recurrence

The COVID-19 vaccines mark the first widespread use of mRNA technology. They work by using synthetic genetic code to instruct the patient’s cells to recognize the coronavirus and activate the immune system against the virus. But researchers began exploring how to use mRNA vaccines as a new way to treat cancer long before this technology was used against the coronavirus.

A B-cell displaying antibodies created in response to foreign protein fragments produced from a personalized mRNA vaccine recognizes a colorectal cancer cell and signals killer T-cells to destroy it

We’ve known about this technology for a long time, well before COVID-19,” says Van Morris, M.D. Here, he explains how mRNA vaccines work and how a team of MD Anderson colorectal cancer experts led by Scott Kopetz, M.D., Ph.D., are testing the technology in a Phase II clinical trial, following high-risk patients with stage II or stage III colorectal cancer who test positive for circulating tumor DNA after surgery.

The presence of circulating tumor DNA is checked with a blood test. “If there is ctDNA present, it can mean that a patient is at higher risk for the cancer coming back,” Morris says. The opposite can also be true: if there is not circulating tumor DNA present, the patient may have a lower risk of recurrence, he adds.

In the Phase II clinical trial, enrolled patients start chemotherapy after the tumor is surgically removed. Tissue from the tumor is sent off to a specialized lab, where it’s tested to look for genetic mutations that fuel the cancer’s growth. Morris explains anywhere from five to 20 mutations specific to that patient’s tumor can be identified during testing. The mutations are then prioritized by the most common to the least common, and an mRNA vaccine is created based on that ranking. “Each patient on the trial receives a personalized mRNA vaccine based on their individual mutation test results from their tumor.

As with the COVID-19 vaccines, the mRNA instructs the patient’s cells to produce protein fragments based off tumor’s genetic mutations identified during testing. The immune system then searches for other cells with the mutated proteins and clears out any remaining circulating tumor cells.We’re hopeful that with the personalized vaccine, we’re priming the immune system to go after the residual tumor cells, clear them out and cure the patient,” says Morris.

Source: https://www.mdanderson.org/