NTHU Researchers Unveil the Mystery of Cancer Cells' Sugar Addiction
In this groundbreaking interdisciplinary research, Lin worked on the cell biology of cancer cells and Cheng provided the protein structure analysis. They had been classmates in the Department of Life Sciences, NTHU, and after returning to their alma mater to teach, they began to regularly discuss their research. By combining their areas of expertise, they succeeded in finding a way to inhibit the proliferation of cancer cells.
German scientist Otto H. Warburg discovered the unique respiration of cancer cells a hundred years ago. Normal cells generate energy by using oxygen for aerobic respiration; by contrast, even in an environment with sufficient oxygen, cancer cells tend to consume glucose mainly through a metabolic pathway called glycolysis, a process that provides precursors for the synthesis of DNA, RNA, and protein---the nutrients required for rapid tumor growth. This discovery was named the Warburg effect and earned him the Nobel Prize.
But why are cancer cells so fond of consuming glucose? For a century, this question lacked a complete explanation-until the recent work by Lin and Cheng added a crucial piece to the puzzle.
Lin said that in a hypoxic tumor microenvironment, cancer cells secrete hydrogen sulfide and send a signal to the tetrameric protein pyruvate kinase (PKM2), causing it to break down into smaller dimers or monomers. In this modified mode of activity, cancer cells begin to absorb more glucose and to synthesize DNA, resulting in rapid proliferation.
Cheng added that just as a logistics system requires a barcode to deliver a package to its destination, hydrogen sulfide also puts a mark at specific positions on PKM2 protein, changing its structure and activity. "As soon as the logistics barcode is changed, the pathway used by cancer cells to metabolize glucose is also changed,” Cheng explained.
The research team used gene editing technology to prevent hydrogen sulfide from marking specific positions on pyruvate kinase, which allows it to maintain its original tetramer structure consisting of larger molecules, and causes cancer cells to resume aerobic respiration. When the cells no longer utilize nutrients by consuming glucose, the tumor can't grow.
The research team also conducted experiments on mice to confirm that their findings can effectively suppress the growth of breast cancer tumors "We are hoping to use this new strategy to develop a new drug for treating cancer,” Lin pointed out.
In addition to Lin and Cheng, the team included two other female scientists at NTHU: Distinguished Professor Wen-Ching Wang of the Department of Life Sciences, who provided key protein materials; and Professor Lily Wang of the Institute of Molecular and Cellular Biology, who assisted in microscopic analysis.
The research team is particularly grateful to Lu-Hai Wang, vice president of the University of Chinese Medicine, and Hsing-Jien Kung, chair professor at Taipei Medical University, for their valuable expertise and for providing an opportunity to translate the findings to clinical applications.
Contact:
Holly Hsueh
NTHU
(886)3-5162006
A photo accompanying this announcement is available at https://www.globenewswire.com/NewsRoom/AttachmentNg/44de3624-34f6-46d1-b11a-4e1c662ddeeb
