The epigenetic reader protein SPIN1 controls proliferation and survival of liposarcoma by modulating the RET signaling pathway [RNA-Seq]

The aim of this study is to identify the SPIN1 target genes in liposarcoma cells Overall design: Liposarcoma is one of the most common histological subtypes of soft tissue sarcoma and causes high incidence of morbidity and mortality. Since therapeutic options for liposarcoma treatment are insufficient, there is an urgent need to identify novel therapeutic targets. Here, we show that knockdown of SPIN1, a reader of H3K4me3 and H3R8me2a chromatin marks, strongly reduces proliferation and survival of liposarcoma cells in vitro and in xenograft mouse models. Combining genome-wide chromatin binding and transcriptome analyses, we found that SPIN1 in cooperation with the transcription factor MAZ directly enhances expression of GDNF, an activator of the RET signaling pathway. Accordingly, knockdown of SPIN1 results in reduced levels of GDNF and activated RET explaining diminished liposarcoma cell proliferation and survival. In line with these observations, levels of SPIN1, GDNF, and activated RET are highly increased in human liposarcoma compared to lipoma or normal adipose tissue. Importantly, SPIN1-mediated transcriptional control depends on binding to H3K4me3 suggesting that targeting of this interaction with small molecule inhibitors is a novel strategy to treat liposarcoma.

5

Franz H, Greschik H, Willmann D, Ozretić L, Jilg CA, Wardelmann E, Jung M, Buettner R, Schüle R