Department of Urology, Peking University First Hospital and Institute of Urology, Peking University, Beijing, China.
Prostate. 2010 May 15;70(7):797-805. doi: 10.1002/pros.21113.
Eleven-nineteen lysine-rich leukemia (ELL) plays an important role in tumorigenesis and animal development. HIF-1 is a transcriptional factor that functions as a master regulator of O(2) homeostasis. Our previous studies showed that a binding partner of ELL, U19/Eaf2, can modulate HIF-1alpha activity and hypoxia response, suggesting that ELL may also influence HIF-1alpha pathway and hypoxia response.
Co-localization and co-immunoprecipitation were performed to test the interaction between ELL and HIF-1alpha. PC3 cells with stable ELL knockdown and PC3 cells with stable ELL overexpression, along with their controls, were established using lentiviral expression system. Western blot and real-time PCR were performed to test the effect of ELL on HIF-1alpha protein and its down-stream gene transcription. To elucidate potential effect of hypoxia on ELL, cell growth and colony formation assays were performed using PC3 subline with stable ELL overexpression.
ELL is associated with HIF-1alpha in transfected cells. In PC3 prostate cancer cells, ELL inhibited HIF-1alpha protein level and down-stream gene expression. As expected, ELL inhibited cell growth and colony formation under normoxia. Interestingly, the inhibition was alleviated under hypoxia.
Our findings suggest that ELL and HIF-1alpha are binding partners and can modulate the functions of each other in hypoxia.
十一号十九赖氨酸丰富白血病（ELL）在肿瘤发生和动物发育中起着重要作用。HIF-1 是一种转录因子，作为 O（2）稳态的主调控因子。我们之前的研究表明，ELL 的结合伙伴 U19/Eaf2 可以调节 HIF-1alpha 活性和低氧反应，这表明 ELL 也可能影响 HIF-1alpha 途径和低氧反应。
共定位和共免疫沉淀用于测试 ELL 和 HIF-1alpha 之间的相互作用。使用慢病毒表达系统建立了具有稳定 ELL 敲低的 PC3 细胞和具有稳定 ELL 过表达的 PC3 细胞及其对照细胞。Western blot 和实时 PCR 用于测试 ELL 对 HIF-1alpha 蛋白及其下游基因转录的影响。为了阐明缺氧对 ELL 的潜在影响，使用具有稳定 ELL 过表达的 PC3 亚系进行了细胞生长和集落形成测定。
ELL 与转染细胞中的 HIF-1alpha 相关。在前列腺癌细胞 PC3 中，ELL 抑制了 HIF-1alpha 蛋白水平及其下游基因表达。正如预期的那样，ELL 在常氧下抑制了细胞生长和集落形成。有趣的是，在缺氧下，抑制作用得到缓解。
我们的研究结果表明，ELL 和 HIF-1alpha 是结合伙伴，可以在低氧条件下相互调节彼此的功能。
