Correlation of WWOX, RUNX2 and VEGFA protein expression in human osteosarcoma

Abstract

BackgroundTo investigate associations between WW domain-containing oxidoreductase (WWOX), runt-related transcription factor 2 (RUNX2) and vascular endothelial growth factor alpha (VEGFA) in human osteosarcoma (OS).MethodsCopy number aberrations of WWOX, RUNX2and VEGFA genes were detected by microarray comparative genomic hybridization (aCGH) in 10 fresh OS tissue samples. VEGFA gene alterations were also investigated and validated by fluorescence in situ hybridization (FISH) in 54 formalin-fixed and paraffin-embedded (FFPE) OS samples. Protein expression of WWOX, RUNX2 and VEGFA were examined in 54 FFPE OS samples by immunohistochemistry (IHC).ResultsAnalysis of previously published OS aCGH data (GSE9654) and aCGH data from this study (GSE19180) identified significant deletion of WWOX in 30% (6/20) of OS samples, whilst significant increase in both RUNX2 and VEGFA gene copy numbers were detected in 55% (11/20) and 60% (12/20) of OS samples, respectively. FISH demonstrated increased VEGFA gene copy number in 65.9% (31/47) of evaluable samples, in either focal or large fragment forms. Compared with positive expression of WWOX in 38.9% of the OS samples, positive expression of RUNX2 and VEGFA protein was found in 48.1 and 75.9% of samples. Although there was no significant association between gene copy number aberration and protein expression for WWOX and RUNX2, significant positive correlation between increased VEGFA gene copy number and VEGFA protein expression was observed. Although there was no significant reverse association between WWOX and RUNX2 expression, a significantly positive relationship was observed between RUNX2 and VEGFA protein expression.ConclusionsOur data show increased RUNX2 and VEGFA gene copy numbers and elevation of their respective proteins in human OS. Positive correlation of RUNX2 and VEGFA suggests that both increased VEGFA gene copy number and RUNX2 overexpression facilitate increased expression of VEGFA.

Selective inhibition of BET bromodomain epigenetic signalling interferes with the bone-associated tumour vicious cycle

“…This observation led us to the finding that BET inhibition also resulted in the downregulation of RUNX2 gene expression in osteosarcoma cells. This finding is of clinical relevance, given the emerging role of RUNX2 as a potential oncogene in osteosarcoma [12][13][14][15][16] . In addition, we found that RUNX2 gene expression, as well as that of MYC and BRD4, was higher relative to MSCs in the majority of our human osteosarcoma patient samples suggesting an addiction or at least a dependence to those oncogenes.…”

“…Moreover, MYC overexpression in a Ink4/Arf( À / À ) context was not only sufficient to transform bone marrow stromal cells but also led to osteosarcoma development 11 . In addition, RUNX2, a key transcription factor in OB differentiation, appears to be a potential oncogenic driver in osteosarcoma, depending on its expression level and cellular context [12][13][14][15] . Indeed, short interfering RNA (siRNA) knockdown of RUNX2 in U2OS osteosarcoma cells was shown to inhibit cell growth, while overexpression of RUNX2 in T-cell lymphoma synergized with MYC to promote survival and proliferation of cancer cells 13,16 .…”

RYBP Expression Is Regulated by KLF4 and Sp1 and Is Related to Hepatocellular Carcinoma Prognosis

“…After the washing step, the sections were incubated with streptavidin-biotin complex and diaminobenzidine and finally counterstained with hematoxylin, dehydrated, and mounted. The expression levels of the three target proteins in each tissue specimen were evaluated as described previously with minor modifications (19).…”

Role of PACAP and VIP Signalling in Regulation of Chondrogenesis and Osteogenesis

“…The expression of these growth factors is also under the control of PKA-Runx2 axis [ 83 ]. Formation and invasion of the blood vessels into the calcifi ed cartilage matrix result in the appearance of osteoprogenitor cells and differentiation of osteoblasts producing the bone matrix.…”