Hematology, Department of Clinical and Experimental Medicine, University of Parma, Parma, Italy.
Leukemia. 2013 Aug;27(8):1697-706. doi: 10.1038/leu.2013.24. Epub 2013 Jan 24.
Hypoxia-inducible transcription factor-1 (HIF-1α) is overexpressed in multiple myeloma (MM) cells within the hypoxic microenvironment. Herein, we explored the effect of persistent HIF-1α inhibition by a lentivirus short hairpin RNA pool on MM cell growth either in vitro or in vivo and on the transcriptional and pro-angiogenic profiles of MM cells. HIF-1α suppression did not have a significant impact on MM cell proliferation and survival in vitro although, increased the antiproliferative effect of lenalidomide. On the other hand, we found that HIF-1α inhibition in MM cells downregulates the pro-angiogenic genes VEGF, IL8, IL10, CCL2, CCL5 and MMP9. Pro-osteoclastogenic cytokines were also inhibited, such as IL-7 and CCL3/MIP-1α. The effect of HIF-1α inhibition was assessed in vivo in nonobese diabetic/severe combined immunodeficiency mice both in a subcutaneous and an intratibial MM model. HIF-1α inhibition caused a dramatic reduction in the weight and volume of the tumor burden in both mouse models. Moreover, a significant reduction of the number of vessels and vascular endothelial growth factors (VEGFs) immunostaining was observed. Finally, in the intratibial experiments, HIF-1α inhibition significantly blocked bone destruction. Overall, our data indicate that HIF-1α suppression in MM cells significantly blocks MM-induced angiogenesis and reduces MM tumor burden and bone destruction in vivo, supporting HIF-1α as a potential therapeutic target in MM.
缺氧诱导因子-1(HIF-1α)在多发性骨髓瘤(MM)细胞的低氧微环境中过表达。在此,我们通过慢病毒短发夹 RNA 池探索了持续抑制 HIF-1α对 MM 细胞在体外或体内生长的影响,以及对 MM 细胞转录和促血管生成特征的影响。HIF-1α 抑制虽然增加了来那度胺的抗增殖作用,但对 MM 细胞在体外的增殖和存活没有显著影响。另一方面,我们发现 HIF-1α 抑制 MM 细胞下调促血管生成基因 VEGF、IL8、IL10、CCL2、CCL5 和 MMP9。还抑制了促破骨细胞生成细胞因子,如 IL-7 和 CCL3/MIP-1α。我们在非肥胖糖尿病/严重联合免疫缺陷小鼠的皮下和胫骨内 MM 模型中评估了 HIF-1α 抑制的体内作用。HIF-1α 抑制导致两种小鼠模型的肿瘤负担的重量和体积显著减少。此外,观察到血管和血管内皮生长因子(VEGFs)免疫染色的数量显著减少。最后,在胫骨内实验中,HIF-1α 抑制显著阻止了骨破坏。总的来说,我们的数据表明,MM 细胞中 HIF-1α 的抑制可显著阻断 MM 诱导的血管生成,并减少体内 MM 肿瘤负担和骨破坏,支持 HIF-1α 作为 MM 的潜在治疗靶点。