NRG2 and gastric cancer: Because various tumor growth and angiogenic factors have been determined to be downstream genes regulated by HOXB9 [16], we examined the mRNA level of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), transforming growth factor-β (TGF-β), and neuregulin-2 (NRG2) in GC cells expressing vector only or WT HOXB9 or ΔH9 mutant (Figure 7).