Effects of HLEC on the secreted proteins of epithelial ovarian cancer cells prone to metastasize to lymph nodes

Objective： To study explores the effect of HLEC on the secreted proteins of epithelial ovarian cancer （EOC） cells （SKOV3-PM4） with directional highly lymphatic metastasis. Methods： Supernatants of four groups of cultured cells, namely, SKOV3 （A）, SKOV3＋HLEC （B）, SKOV3-PM4 （C）, SKOV3-PM4＋HLEC （D）, were collected, and their proteins were detected by antibody arrays and iTRAOcZD-LC-MALDI- TOF/TOF/MS. Significantly differential proteins were further analyzed via bioinformatics and validated in human serums and cell media via ELISA. Results： Results of antibody arrays and mass spectrometry demonstrated that GRN and VEGFA were upregulated in group C （compared with group A）, whereas IGFBP7 and SPARC were downregulated in group D （compared with group C）. Comprehensive bioinformatics analysis results showed that IGFBP7 and VEGFA were closely linked to each other. Further validation with serums showed statistical significance in VEGFA and IGFBP7 levels among groups of patients with ovarian cancers, benign tumors, and control groups. Two proteins were upegulated in the first group. VEGFA in the control group was downregulated. For IGFBP, upregulation in the control group and down-regulation in the first group were also observed. Conclusion： The HLEC microenvironment is closely associated with directional metastasis to lymph nodes and with differential proteins including cell stromal proteins and adhesion factors. The upregulation of VEGFA and GRN and the downregulation of SPARC and IGFBP7 are closely associated with directional metastasis to lymph nodes in EOC cells.

Low molecular weight heparin suppresses lymphatic endothelial cell proliferation induced by vascular endothelial growth factor C in vitro

Background Pancreatic cancer is one of the most aggressive human malignancies. Lymphangiogenesis plays an important role in lymph node metastasis of many solid tumors. It is well known that low molecular weight heparins （LMWHs） can inhibit cell growth, cell invasion and angiogenesis, which are key processes in tumor progression. Methods We measured the expression of vascular endothelial growth factor C （VEGF-C） in pancreatic cancer cells （PANC-1） using reverse transcription-polymerase chain reaction （RT-PCR） and Western blotting. We used an in vitro assay to evaluate the anti-lymphangiogenic effect of an LMWH, Fragmin, on human lymphatic endothelial cell （HLEC） proliferation. Results Fragmin at a low concentration can effectively inhibits HLEC proliferation induced by VEGF-C. VEGF-C secreted by PANC-1 cells stimulated HLEC proliferation. Low concentration LMWH suppressed HLEC proliferation induced by VEGF-C but did not affect proliferation or VEGF-C expression of PANC-1 cells, whereas high concentrations of LMWH inhibited PANC-1 cell proliferation. Conclusions These results suggest that VEGF-C released by cancer cells plays an important role in promoting HLEC proliferation. The LMWH Fragmin has anti-lymphangiogenic effects and may inhibit lymphatic metastasis in pancreatic cancer.