Discovery with cancer research impact makes scientists dance in lab

For years, scientists in this field continued to be intrigued by the existence of two forms- PRC2.1 and PRC2.2- in the cell that were shown to target the same regions of DNA yet did the same job. Why was this so? Surely one version would suffice, right? 

This conundrum has finally been answered. The team found that PRC2.1 and PRC2.2 recruit different forms of the PRC1 complex, explaining the existence of the two versions. 

Dr. Eleanor Glancy, a Ph.D. graduate of the Bracken lab, describes the evening when the team finally made sense of the data in front of them. “We initially thought there must have been a technical issue with the experiment, but multiple replications confirmed that we had stumbled upon a fascinating new process that reshapes our understanding of the hierarchical workflow of Polycomb complexes. This took us by complete surprise. We were dancing around the lab,” she recalls. 

The team, spearheaded by Dr. Glancy and Postdoctoral researcher Dr. Cheng Wang in collaboration with scientists in Italy and Netherlands, published their work in the leading journal Molecular Cell.

Their findings are of great relevance to the field of chromatin and epigenetics research and can impact cancer biology research as genes encoding Polycomb proteins are frequently mutated in cancers. 

Professor Bracken and his team worked through the COVID-19 pandemic shutdown keeping up with their tight deadlines and undeterred by failed hypotheses and failed experiments while maintaining social distancing measures to attain this significant breakthrough.

The team currently studies the effects of these mutations in childhood brain cancers and adult lymphomas to gain a better understanding of the biological mechanisms gone rogue, and how they can be targeted to reach more effective treatments. “A firm and comprehensive understanding of the workings of these complexes is critical to figuring out new ways to target them in cancer settings,” added Professor Bracken.

Study Abstract

A team of scientists based in Trinity College Dublin talks about their discovery and reasons behind the existence of PRC2.1 and PRC2.2, two Polycomb protein complexes critical to maintaining cellular identity, and their potential impact on cancer treatment research.