Cancer cells have learned and evolved to display a protein on their surface that sends a negative stopping signal to our immune system, halting our immune system from activating and recognizing the cancer cells.
Immunotherapy tries to induce our immune system to recognize and kill the cancer by blocking cancer cells from highjacking that checkpoint mechanism. These drugs are known as checkpoint inhibitors. They act by interfering with the cascade of signals sent by the cancer cell and liberate the immune cells for a successful anti-cancer attack.
Our immune system, especially when faced with cancer cells, can experience what is called immune cell exhaustion. Immune cells become so tired of seeing cancer cells around that they essentially get used to them and give up. This is why introducing only a checkpoint inhibitor will not work. The immune system is still too weak to activate.
What happens when immunotherapy does not work because our immune system is too weak to activate?
Mayo Clinic researchers are combining a checkpoint inhibitor to bypass the negative signal from the cancer cell and another drug to give the immune system a boost to strengthen our response.
“What we are trying to do is to block the signal from the cancer cell, and at the same time give a second positive signal that pushes our immune cells to activate,” says hematologist J. C. Villasboas, M.D.
“Because we are now trying to modulate two different signals, both the negative (inhibitor) and positive signals, we are calling this therapy a dual-immunomodulatorytherapy.”
According to Dr. Villasboas, this is the first big study where these two drugs are being combined to fight aggressive lymphomas that otherwise have not responded to conventional treatments.
Although the current study is looking specifically at the effectiveness in patients with aggressive B cell non-Hodgkin’s lymphoma, the implications could be vast.
“This study on dual-immunomodulation, if effective, could be a launching point for treating many different types of cancers,” says Dr. Villasboas. “It could be revolutionary in cancer treatment and it is very exciting.”