Yang Lily, Kang Won-Kyung
Department of Surgery, Winship Cancer Institute, Emory University, Atlanta, GA, USA.
Yonsei Med J. 2008 Apr 30;49(2):295-300. doi: 10.3349/ymj.2008.49.2.295.
Hypoxia-inducible factor-1alpha (HIF-1alpha) primarily mediates the hypoxic response. HIF-1alpha induction by various stimuli contributes to cell proliferation and survival. To investigate the effect of HIF-1alpha, we used small interfering RNA (siRNA), and expected that cell apoptosis and sensitivity to chemotherapeutic drug increase, when we blocked the HIF-1alpha gene. Thus we performed in vitro and in vivo experiment to clarify the effect of hypoxia-inducible factor-1alpha on tumor growth.
We made control and HIF-1alpha siRNA using vector plasmid and then transfected Mia-paca cell lines with these RNAs. After selection with geneticin, two new cell lines were made, confirmed via immunoblotting. After treating with gemcitabine, each cell line was assayed to confirm the effect of HIF-1alpha siRNA using the cell proliferation assay and capase-3 assay. And then in vivo study was performed using female athymic nude mice. After subcutaneously injecting each new cell lines, intraperitoneal gemicitabine chemotherapy was performed for 3 weeks. During that period, we analyzed the difference of tumor growth rate.
The tumor growth of HIF-1alpha siRNA-transfected group was slower than that of the control group both in vitro and in vivo experiment.
The suppression of HIF-1alpha results in decrease of cell proliferation and increase of chemosensitivity of pancreatic cancer cell line. Therefore, targeting the HIF-1alpha may be useful treatment modality for some pancreatic cancers.
缺氧诱导因子-1α（HIF-1α）主要介导缺氧反应。各种刺激诱导HIF-1α有助于细胞增殖和存活。为了研究HIF-1α的作用，我们使用了小干扰RNA（siRNA），并期望当我们阻断HIF-1α基因时，细胞凋亡和对化疗药物的敏感性会增加。因此，我们进行了体外和体内实验，以阐明缺氧诱导因子-1α对肿瘤生长的影响。
我们使用载体质粒制备了对照和HIF-1α siRNA，然后用这些RNA转染Mia-paca细胞系。用遗传霉素筛选后，建立了两个新的细胞系，并通过免疫印迹进行了确认。用吉西他滨处理后，使用细胞增殖测定法和半胱天冬酶-3测定法对每个细胞系进行检测，以确认HIF-1α siRNA的作用。然后使用雌性无胸腺裸鼠进行体内研究。皮下注射每种新细胞系后，进行为期3周的腹腔内吉西他滨化疗。在此期间，我们分析了肿瘤生长速率的差异。
在体外和体内实验中，转染HIF-1α siRNA的组的肿瘤生长均比对照组慢。
抑制HIF-1α导致胰腺癌细胞系的细胞增殖减少和化学敏感性增加。因此，靶向HIF-1α可能是某些胰腺癌的有用治疗方式。
