Schwartz B M, Hong G, Morrison B H, Wu W, Baudhuin L M, Xiao Y J, Mok S C, Xu Y
Department of Cancer Biology, Department of Gynecology and Obstetrics, Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, OH 44195, USA.
Gynecol Oncol. 2001 May;81(2):291-300. doi: 10.1006/gyno.2001.6124.
We have previously described that bioactive lysophospholipids-lysophosphatidic acid (LPA), sphingosine 1-phosphate (S1P), and sphingosylphosphorylcholine (SPC)-are present in ascitic fluids from patients with ovarian cancer. To understand the role of these lipids in ovarian cancer, we investigated the effects of these lipids on interleukin-8 (IL-8) production in ovarian cancer cells. IL-8 is a proinflammatory and proangiogenic factor, which is potentially involved in ovarian cancer development.
The Clontech PCR-Select cDNA subtraction method (Clontech Laboratories, Inc., Palo Alto, CA) was used to identify genes potentially regulated by LPA in HEY and OCC1 ovarian cancer cell lines. Northern blot analysis was used to confirm and examine IL-8 mRNA regulation by lysolipids. Enzyme-linked immunosorbent assay (ELISA) was used for detecting secreted IL-8.
We describe here that LPA, S1P, and SPC increased mRNA levels (2- to 7-fold) and protein secretion (2- to 12-fold) of IL-8 from ovarian cancer cells (HEY, OCC1, and SKOV3) in vitro. These regulations were both dose- and time-dependent. All three lipids increased the stability IL-8 mRNA in HEY cells. In contrast to malignant ovarian cancer cells, immortalized human ovarian epithelial cells did not respond to any of these lipids to increase the secretion of IL-8, although these cells secreted similar basal levels of IL-8 (310 pg/ml/10,000 cells). Two breast cancer cell lines (MCF7 and T47D) secreted lower basal levels of IL-8 (48-80 pg/ml/10,000 cells), compared with ovarian cancer cells (200-500 pg/ml/10,000 cells). MCF7 cells responded to LPA, but not S1P and SPC, by increasing the secretion of IL-8. T47D and MCF10A, an immortalized breast cell line, did not respond to LPA, S1P, or SPC to increase IL-8 secretion.
LPA, S1P, and SPC regulate the mRNA and protein levels of the proinflammatory and proangiogenic factor IL-8 in ovarian cancer cells. The pathological significance of these regulations in ovarian cancer remains to be further investigated.
我们之前曾描述过，生物活性溶血磷脂——溶血磷脂酸（LPA）、1-磷酸鞘氨醇（S1P）和鞘氨醇磷酰胆碱（SPC）——存在于卵巢癌患者的腹水中。为了解这些脂质在卵巢癌中的作用，我们研究了这些脂质对卵巢癌细胞中白细胞介素-8（IL-8）产生的影响。IL-8是一种促炎和促血管生成因子，可能参与卵巢癌的发展。
采用Clontech PCR-Select cDNA扣除法（Clontech Laboratories公司，加利福尼亚州帕洛阿尔托）来鉴定在HEY和OCC1卵巢癌细胞系中可能受LPA调控的基因。Northern印迹分析用于确认和检测溶血磷脂对IL-8 mRNA的调控。酶联免疫吸附测定（ELISA）用于检测分泌的IL-8。
我们在此描述，LPA、S1P和SPC在体外可使卵巢癌细胞（HEY、OCC1和SKOV3）中IL-8的mRNA水平升高（2至7倍）以及蛋白质分泌增加（2至12倍）。这些调控具有剂量和时间依赖性。所有这三种脂质均增加了HEY细胞中IL-8 mRNA的稳定性。与恶性卵巢癌细胞不同，永生化人卵巢上皮细胞对这些脂质均无反应，不会增加IL-8的分泌，尽管这些细胞分泌的基础水平的IL-8相似（310 pg/ml/10,000个细胞）。与卵巢癌细胞（200 - 500 pg/ml/10,000个细胞）相比，两种乳腺癌细胞系（MCF7和T47D）分泌的基础水平的IL-8较低（48 - 80 pg/ml/10,000个细胞）。MCF7细胞对LPA有反应，可增加IL-8的分泌，但对S1P和SPC无反应。T47D和永生化乳腺细胞系MCF10A对LPA、S1P或SPC均无反应，不会增加IL-8的分泌。
LPA、S1P和SPC可调节卵巢癌细胞中促炎和促血管生成因子IL-8的mRNA和蛋白质水平。这些调控在卵巢癌中的病理意义仍有待进一步研究。
