James P. Allison and Tasuku Honjo are the winners of the 2018 Nobel Prize in Medicine. The Swedish Academy announced this Monday (01) that the American and Japanese will share the prize of 9 million Swedish crowns, equivalent to R$4.098.402.
The two developed research into two proteins produced by tumors — CTLA-4 and PD-1 — that paralyze the patient's immune system during cancer treatment.
"Tumors produce proteins, called checkpoints, that block the T lymphocyte, which is the most important cell of the immune system that attacks the tumor. These drugs [researched] remove this blockade and recover the attacking power of the lymphocytes that were paralyzed by these proteins", explains oncologist Fernando Maluf, associate director of the Beneficência Portuguesa Oncology Center in São Paulo.
Immunologist James P. Allison at the University of Texas studied the CTLA-4 protein. He discovered that blocking the protein could remove the brake on T lymphocytes, causing the cells to attack the tumor again. In 1994, Allison carried out the first experiment on rats, which were cured after treatment.
In 2010, a clinical study showed "impressive" effects, according to the Swedish Academy, in patients with advanced melanoma (a type of skin cancer), which had not been observed before.
Immunologist Tasuku Honjo, from Kyoto University, in Japan, studied another protein, PD-1, which also acted on T lymphocytes, but in a different way. After laboratory experiments, a study carried out in 2012 also demonstrated its effectiveness in treating patients with different types of cancer.
"The results have been dramatic, with long-term remission and possible cure in some patients with metastatic cancer, a condition previously considered largely untreatable," the Academy said.
Maluf explains that this type of treatment has already been used in patients with advanced cancer, in Brazil and around the world, for around four years. In the country, there is one drug that blocks CTLA-4 and five others that act on PD-1. He explains that they are normally used in people who have not responded to other treatments.
"These drugs have been associated with gains in overall survival in serious tumors such as melanoma, lung, bladder, kidney, head and neck cancer, lymphoma, intestinal, liver and gastric tumors as well. These are drugs that are now part of the everyday daily in several important situations with serious and very advanced tumors", he states. The oncologist explains that they also have fewer side effects than traditional chemotherapy.
The Swedish Academy considered that the clinical development of immunotherapy strategies had been modest until the discoveries of James P. Allison and Tasuku Honjo. Scientists have been trying to activate the immune system to fight cancer for more than 100 years.
The Nobel Foundation will announce the winners in Physics this Tuesday (2) and in Chemistry this Wednesday (3). The winners in the Peace and Economy category will be announced on Friday (5) and Monday (11), respectively. The Literature prize has been postponed until 2019.
(Lara Pinheiro, G1)
