by Fu Yiming, He Miao, Zhang Jiawei

STOCKHOLM, Oct. 1 (Xinhua) -- Two scientists shared the 2018 Nobel Prize in Physiology or Medicine, the Nobel Committee announced here on Monday.

The Nobel Assembly at the Karolinska Institutet has decided to award the 2018 physiology or medicine prize jointly to James P. Allison and Tasuku Honjo "for their discovery of cancer therapy by inhibition of negative immune regulation."

This year's laureates showed how different strategies for inhibiting the brakes on the immune system can be used in the treatment of cancer. Their discoveries are a landmark in the fight against cancer, the committee said.

Edward Smith, member of the Nobel Committee, told Xinhua that the significance of this year's award pointed to a "new fashion" in cancer treatment. All previous treatments focused on tumor cells, this one on the immune system.

Cancer kills millions of people every year and is one of humanity's greatest health challenges. The Nobel Assembly said in a statement that by stimulating the inherent ability of our immune system to attack tumor cells, this year's Nobel Laureates have established an entirely new principle for cancer therapy.

Allison studied a known protein that functions as a brake on the immune system. He realized the potential of releasing the brake and thereby unleashing our immune cells to attack tumors. He then developed this concept into a brand new approach for treating patients.

In parallel, Honjo discovered a protein on immune cells and, after careful exploration of its function, eventually revealed that it also operates as a brake, but with a different mechanism of action. Therapies based on his discovery proved to be strikingly effective in the fight against cancer, according to the statement.

"Cancer as a disease is a worldwide problem of major significance," Thomas Perlmann, secretary-general of the Nobel Committee and Nobel Assembly, told Xinhua in an interview after the press conference. "There have been previous awards to cancer researches, and this is what we have found, among all the proposals, of the most significance for this year in particular."

"It's a very exciting development in both basic research and in clinical research. This is so novel. And I think what has been alluded to today is that there is great promise with combination therapies," he said.

"We are all in the beginning both to see how this will work in combination with more conventional therapies, but also with novel ideas, like combining with vaccination against cancer, that have been many attempts in that direction that's mostly have been unsuccessful, but now people are thinking in a more new way to combine other ideas that might affect immune system," Perlmann told Xinhua.

"We should also remember that there are additional 'checkpoint' proteins in addition to those that were mentioned here today -- CTLA-4, PD-1 that have been discovered. We are in a very exciting phase now to see where this will lead us," he added.

James P. Allison, born 1948 in the United States, is a professor at University of Texas MD Anderson Cancer Center, Houston, Texas and is affiliated with the Parker Institute for Cancer Immunotherapy.

Tasuku Honjo, born 1942 in Japan, is a professor at Kyoto University.

This year's prize is 9 million Swedish krona (about 1 million U.S. dollars).