HIF-1α regulates NB growth and the SHH pathway in vivo.

<p>(A) Representative xenografts dissected from different groups of nude mice are shown. (B) The volume of subcutaneous xenografts formed by SH-SY5Y cells stably infected with the indicated lentiviruses is illustrated by growth curves (n = 5). Compared with the control, cells overexpressing HIF-lα formed significantly larger tumors. By contrast, the tumor weight in the HIF-lα knockdown group was significantly reduced. GANT61 could reverse the pro-growth effect of HIF-lα. (C) Immunohistochemical staining of HIF-1α, SHH pathway components and CD31 in xenografts. The statistical results showed that the expression levels of SHH pathway components and angiogenesis in xenografts were correlated with HIF-lα (n = 5). In the bar graph, 4 bars were indicated for HIF-1α and PTCH1 as mean scores for both subgroups were 0. Magnification, ×400. Scale bars, 200 μm. Arrows, positive cells.