GSE245495 A MYOD-SKP2 axis boosts tumorigenesis in fusion negative rhabdomyosarcoma by preventing differentiation through p57Kip2 targeting [Hi-ChIP]

Contributors : Silvia Pomella ; Matteo Cassandri ; Berkley E Gryder ; Rossella RotaSeries Type : Genome binding/occupancy profiling by high throughput sequencing ; OtherOrganism : Homo sapiensRhabdomyosarcoma (RMS) is a pediatric mesenchymal-derived malignancy encompassing Fusion Positive (FP)-RMS expressing PAX3/7-FOXO1 and Fusion Negative (FN)-RMS often mutated in the RAS pathway. RMS expresses the master myogenic transcription factor MYOD that, paradoxically, is unable to support differentiation while essential for tumor cell survival. We identify here SKP2, an oncogenic E3-ubiquitin ligase, as a critical driver of tumorigenesis in FN-RMS. SKP2 is overexpressed in RMS at the highest levels among several adult and pediatric cancers and its expression is maintained by MYOD through an intronic enhancer within the gene. In FN-RMS SKP2 promotes cell cycle progression and prevents differentiation directly targeting p27Kip1 and p57Kip2, respectively, unlocking a transcriptional myogenic program, partly MYOD-dependent, resulting in de novo expression of terminal muscle differentiation markers. SKP2 depletion strongly affects stemness and tumorigenic features in vitro and prevents in vivo tumor growth. The in vitro effects are mirrored by the SKP2 inhibitor SMIP004. Moreover, the investigational NEDDylation inhibitor MLN4924 hampers SKP2 functions restraining FN-RMS cell survival and tumor growth. Our results uncover a MYOD-SKP2 axis crucial for the crosstalk between transcripti...
Source: GEO: Gene Expression Omnibus - Category: Genetics & Stem Cells Tags: Genome binding/occupancy profiling by high throughput sequencing Other Homo sapiens Source Type: research