A new hopeful treatment with nanoparticles MIT researchers developed for them cancers of the ovaries.
Cancer immunotherapy, an approach that uses drugs that stimulate the body’s immune cells to attack tumors, is a promising strategy for treating many types of cancer. However, it is not effective for some tumors, such as ovarian cancer, where the tumors have many mechanisms of immune suppression.
To achieve a better response, MIT researchers designed new nanoparticles that can deliver an immune-stimulating molecule known as IL-12 directly to ovarian tumors. When given together with immunotherapy drugs called checkpoint inhibitors, IL-12 helps the immune system launch an attack on cancer cells.
In 2022 the same researchers had developed nanoparticles that could deliver IL-12 directly to cancer cells, allowing higher doses to be administered without the side effects that accompany the infusion of the drug. However, those particles tended to release their drug too quickly, reducing the effectiveness of the immune response.
In the new study, the researchers modified the nanoparticles so that IL-12 was released more gradually, over about a week, by using a different chemical binding agent to link IL-12 to the particles.
By studying mouse models of ovarian cancer, the researchers found that initially the nanoparticles with IL-12 alone eliminated tumors in 30% of mice. When combined with checkpoint inhibitors, more than 80% of mice were completely cured, even in models highly resistant to the immunotherapy or chemotherapy drugs commonly used in ovarian cancer.
Furthermore, when the mice were re-exposed to tumor cells five months after the initial treatment, to simulate tumor recurrence, their immune cells remembered the tumor proteins and neutralized them again.
The cancer models used were metastatic, so the tumors grew not only in the ovaries but also in the peritoneal cavity, which includes the intestines, liver, pancreas and other instruments. Even the lungs were showing cancer foci.
The researchers are now working with MIT’s Deshpande Center for Technological Innovation to create a start-up company that will further develop the nanoparticle technology.
The research was published in the journal Nature Materials.