Oncostatin M induces epigenetic reprogramming in renal cell carcinoma-associated endothelial cells.

The molecular and functional changes in endothelial cells during disease progression such as cancer have been noted but the mechanism of their activation is still under-studied. Previously we discovered that tumor-derived Oncostatin M induced tumor-associated vascular phenotypes, and the activated endothelial cells in turn promoted tumor progression and metastasis of clear-cell renal cell carcinoma (ccRCC). However, the mechanism of Oncostatin M action remains unknown. Here, we reveal that Oncostatin M signaling triggers specific epigenetic reprogramming of endothelial cells through upregulation of lysine acetyltransferase 6B, leading to increased histone 3 lysine 14 acetylation (H3K14ac) in vitro and in vivo. H3K14ac-modified chromatins upregulate specific gene sets associated with hypoxic response, hyper-angiogenesis, inflammation, and mesenchymal transition. Targeting H3K14ac in endothelial cells by interfering with acetyltransferase 6B function or neutralizing Oncostatin M ameliorates the premalignant hyperplastic phenotypes in the autochthonous ccRCC mouse model and diminishes tumor growth and metastasis in the ccRCC xenograft model.