【摘要】 背景与目的肿瘤组织在快速生长过程中,必然会造成局部组织的缺氧,缺氧环境中,肿瘤细胞的侵袭能力大大增强,本研究通过模拟体内缺氧环境探讨与肿瘤侵袭相关的基质金属蛋白酶(matrix metalloproteinase,MMPs)的变化。方法采用明胶酶活性测定Zymography法、RT-PCR和Westernblot等分子生物学方法,探讨缺氧环境培养的胰腺癌SW1990细胞株明胶酶MMP-2和MMP-9在不同分子水平的改变以及其活性的变化。结果常氧培养条件下,SW1990细胞可产生相对较弱的明胶酶活性。当环境氧浓度低于2%时,MMP鄄9活性明显增强(约为常氧环境时的5.5倍)而MMP-2基本没有变化。Westernblot证实缺氧时SW1990细胞产生的MMP-9较常氧时明显增加,而MMP鄄2分泌水平无变化。SW1990细胞在缺氧条件下培养12h后,MMP-9mRNA的水平分别高于对照组和含有氯化钴培养的SW1990细胞46.1%和56.4%。而使用氯化钴刺激SW1990细胞缺氧诱导因子HIF鄄1琢产生并不能观察到MMP-9发生类似的变化。结论缺氧环境培养的SW1990细胞株的MMP鄄9水平明显升高,MMP鄄2则无明显变化;其活性也发生相应改变,这种改变与缺氧时的HIF鄄1琢水平升高无关。更多还原

【Abstract】 BACKGROUND & OBJECTIVE: The malignant tumor tissues usually suffer from hypoxia due to its fast growth, which increases its invasive ability. This study was to explore changes of matrix metalloprotei-nases (MMPs) in tumor cells under hypoxia in vitro. METHODS: Zymography was used to determine the changes of activities of MMP-2 and MMP-9 in pancreatic cancer cell line SW1990 cultured under hypoxia. Western blot, and reverse transcription-polymerase chain reaction (RT-PCR) were used to detect protein and mRNA levels of MMP-2 and MMP-9. RESULTS: Under normal circumstances, activities of MMPs in SW1990 cells were relatively low. When SW1990 cells were cultured under hypoxia, the activity of MMP-9 increased by about 5.5 times that in normal circumstances, while the activity of MMP-2 didn’t change. The same changes in protein level of MMP-9 had been confirmed by Western blot, while protein level of MMP-2 didn’t change. mRNA level of MMP-9 was higher in cells cultured under hypoxia for 12 h than in control cells and CoCl2-cultured tumor cells by 46.1% and 56.4%, but no change of MMP-9 was seen when hypoxia inducible factor-1α (HIF-1α) was produced in SW1990 cells stimulated by CoCl2. CONCLUSIONS: Production of MMP-9 in SW1990 cells is enhanced significantly under hypoxia, and its activity altered correspondingly; but those of MMP-2 had no change. This alteration has no relation with enhancement of HIF-1?琢 under hypoxia.更多还原