A Promising Strategy to Boost the Effectiveness of Cancer Immunotherapy

MIT Engineers have come up with a promising strategy that can boost cancer immunotherapy. They have designed nanoparticles that can be used with checkpoint inhibitors to help stimulate the body’s immune system to attack tumors.

This type of approach is more powerful than using checkpoint inhibitors alone, and many patients are going to benefit from it.

The team created a way to package and deliver small DNA pieces that stimulate the immune response to tumors and produce a synergistic effect that causes checkpoint inhibitors to be more effective. During the research, it was discovered that the dual treatment stopped tumor growth.

The immune system is designed to identify and kill any abnormal cells in the body, including cancer cells. However, most tumors secrete molecules that suppress the immune system in areas surrounding the tumor, making T cell attack useless.

Checkpoint inhibitors can trigger the immune system and restore the ability of T cells to attack the tumors. Some inhibitors target checkpoint proteins such as PD-1, CTLA-4, and PD-L1 can treat several cancers. The drugs can turn off checkpoint proteins that prevent the activation of T cells.

Although the drugs work well for some patients with specific cancers, more studies and trials are needed to make them work for many more patients.

Other studies observed that using checkpoint inhibitors in combination with radiation therapy can make them work effectively. In another unsuccessful approach, researchers tried to combine them with immunostimulatory drugs such as oligonucleotides, which are specific sequences of RNA and DNA recognized by the immune system as foreign. But the problem was that the drugs do not reach the intended targets, so they had to devise another way.

The MIT team sought to find a better way to target the delivery of the immunostimulatory drugs to allow them to accumulate at the tumor locations. They did this by packaging oligonucleotides into tumor-penetrating peptides to deliver RNA to suppress cancerous genes. The peptides will interact with proteins in cancer cells and specifically target the tumors.

The team is now planning to carry out safety testing of the nanoparticles to develop them further so they can treat patients with tumors that don’t respond to checkpoint inhibitor drugs. They’re optimistic that they’ll be able to scale up, manufacture, and advance them for the benefit of the patients.