by Chi-Kwok CHAN

The global immune checkpoint inhibitors market was valued at US$ 10,566 million in 2017, and is projected to reach US$ 56,530 million by 2025, registering a compound annual growth rate (CAGR) of 20.1% from 2018 to 2025 (the accumulative gross total is more than enough to build as many as three 1700-hectare reclamation artificial islands next to Lantau island – promulgated by Ms Carrie LAM in her “Lantau Tomorrow Vision 明⽇⼤嶼願景” project.) Since the first approval by FDA in May 2016 to treating urological malignancy, immunotherapy has transformed the prognostic landscape in a subset of urothelial carcinoma and renal cell carcinoma patients with metastatic diseases notoriously associated with very poor prognosis. In parallel with the success in treating other metastatic cancers like melanoma, lung cancer and lymphoma, Nobel Assembly at the Karolinska Institute in Sweden decided to award the Nobel prize in Physiology and Medicine 2018 to Prof. James Allison of MD Anderson Cancer Center and Prof. Tasuku Honjo of Kyoto University. Prof. Allison worked on CTLA-4 (N.B. he is not the first one discovering CTLA-4, which was actually first identified and cloned by Dariavach in 1987), whereas Prof. Honjo was the first one to clone PD-1 in 1992. However, Prof Honjo knew neither of the exact function of PD-1 nor its link to cancer growth / T cell death at that time.

In 1999, a young researcher from mainland China, working as pre-clinical grantee at the Mayo clinic, called Lieping CHEN (陳列平), at the age of 39, was the first one to discover a surface
molecule he called B7-H1 expressed by several types of tumours in mice and that its activity can cause the death of T cells, thus preventing them from eliminating cancer cells. He also showed the
interaction between PD-1 and B7-H1, cloned immunoglobulins against B7-H1, paving a new way to immunotherapy against cancer. Other researchers, including Prof. Honjo, followed this new idea
and continued the enormous amount of studies on it subsequently. Prof. Honjo, later changed the name of B7-H1 to now what we call PD-L1 in 2000 together with Prof. Gordon Freeman of Harvard
Medical School.

CHEN was born in a farming village in Fujian in 1960. He was among the first batch of high school students sitting for National Higher Education Entrance Examination (⾼考) right after the end of
Cultural Revolution. He graduated from the medical college of Fujian University and was later trained in Peking Union Medical College (北京協和醫學院) , before moving to the USA in 1986 for his
PhD degree. He is now the Co-Director of Cancer Immunology Program at Yale University.