IDENTIFYING ROLE OF YB1 AND NPM1 AS PART OF HISTONE 3 MUTANT PROTEIN INTERACTOME, IN H3 MUTATED PHGG

Abstract

Abstract AIMS Paediatric high-grade gliomas (pHGG) are the leading cause of childhood cancer deaths, accounting for over 40% of deaths in the UK. pHGG tumours harbour histone H3 mutations, defining 50% of pHGG cases. Studies show prominent mutations as being H3.3K27M and H3.3G34R/V. Our previous research has identified unique and common interacting binding partners of H3-G34R and H3-G34V mutant proteins. Among these we have focused on YB-1 and Nucleophosmin (NPM1). YB-1 is multifunctional transcription factor and a well-known oncogenic protein. NPM1 is a molecular chaperone and frequently over- expressed in cancer as well. Our aim is to analyse the role of YB-1 and NPM1 in H3 mutated pHGG, in order to identify targeted therapeutic option for these diffcult to treat tumours. METHOD Further data analyses of mass spectrometric proteomic data were performed. Subsequently, H3 mutated glioma cell lines, and control H3 wild type pHGG cells were cultured and then subjected to proteomic analyses. A comparative immunofluorescence and microscopy, and western blot analyses were performed to investigate the role of YB-1 and NPM-1. RESULTS Results verified the proteomic data and further showed altered protein expression of YB-1 and altered localization of protein NPM1 in H3 mutated pHGG. CONCLUSIONS Results of the study support that YB-1 and NPM1 are important interacting proteins in H3G34-mutated pHGGs and can be explored as therapeutic targets in H3 mutated pHGG.