The two Nobel Laureates in Physiology or Medicine 2018, James Allison and Tasuku Honjo, independently discovered that the reactivation of the immune system by blocking two major negative regulators, CTLA4 and PD-1, can cure a significant portion of cancer patients.
“As a result, Jim and I have experienced many occasions that have made us feel well rewarded, such as meeting cancer patients who say their lives were saved by our therapies,” stated Honjo in his Nobel banquet speech on December 10th 2018.
Never forget what you really want to do
But Tasuku Honjo did not set out to discover a cure, or a therapy. “I never expected my research working on the immune system would lead to the cancer therapy,” he said in an interview with Nobel Media right after the Nobel announcements.
When he and his colleagues first isolated PD-1 they did not know what the function of this molecule would be and it took them almost ten years to realize its important function in regulating the immune system.
Honjo has in previous interviews both emphasized the importance of persistence and of performing basic science. And he advises young scientists to follow their curiosity.
”Sometimes, a direct attack may be difficult. You can take a round route or a side tour but never forget what you really want to do,” he says.
What Honjo and his colleagues were able to show, through persistence and performing basic research, was a checkpoint protein (PD-1) in T cells that acts as a type of “off switch” to help the T cells from attacking other cells. Later, drug developers came up with medicines to target those brakes. Those drugs, such as Keytruda and Opdivo, are now widely used drugs to treat many different types of cancer.