Cancer cells become deadly when they proliferate uncontrollably and overwhelm their healthy neighbors. Last July, biologists at University College London and Florida State University collaborated to tease out a crucial detail of how the process unfolds. The researchers identified a new gene, dubbed “Mahjong,” that determines whether the cancerous cells gain the upper hand.
The researchers began by investigating a gene called Lgl, which normally suppresses tumor growth. Mutant forms of Lgl allow cancerous cells to reproduce unchecked. To understand that process, the Florida State group engineered a fruit fly to produce a mix of cells, some with normal Lgl and some with the altered version. But the mutants actually lost out to the normal cells every time.
Evidently, mutant Lgl is dangerous only when it receives some kind of boost, and the British team isolated that boost: the Mahjong gene. This gene makes a protein that interacts with Lgl protein in a way that is not yet understood, according to Yoichiro Tamori, a postdoc at Florida State. When the Florida researchers raised the concentration of the Mahjong protein, the mutant cells began winning.
The scientists in London got the same result in a similar experiment using mammalian kidney cells, showing that healthy and mutant cells compete directly against each other in mammals. “Especially in early stages, normal cells can kill cancer cells,” says biologist Yasuyuki Fujita, who led the British team. Understanding the lethal alliance between Lgl and Mahjong genes could open the door to new early-stage cancer therapies.