tailieunhanh - báo cáo khoa học: " Cyclooxygenase-2 up-regulates vascular endothelial growth factor via a protein kinase C pathway in non-small cell lung cancer"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: Cyclooxygenase-2 up-regulates vascular endothelial growth factor via a protein kinase C pathway in non-small cell lung cancer | Luo et al. Journal of Experimental Clinical Cancer Research 2011 30 6 http content 30 1 6 Journal of Experimental Clinical Cancer Research RESEARCH Open Access Cyclooxygenase-2 up-regulates vascular endothelial growth factor via a protein kinase C pathway in non-small cell lung cancer 1 f 1 f 1 2 3 1 1 Honghe Luo Zhenguang Chen Hui Jin Mei Zhuang Tao Wang Chunhua Su Yiyan Lei Jianyong Zou1 Beilong Zhong4 Abstract Background Vascular endothelial growth factor VEGF expression is up-regulated via a cyclooxygenase-2 COX-2 -dependent mechanism in non-small cell lung cancer NSCLC but the specific signaling pathway involved is unclear. Our aim was to investigate the signaling pathway that links COX-2 with VEGF up-regulation in NSCLC. Material and methods COX-2 expression in NSCLC samples was detected immunohistochemically and its association with VEGF microvessel density MVD and other clinicopathological characteristics was determined. The effect of COX-2 treatment on the proliferation of NSCLC cells A549 H460 and A431 cell lines was assessed using the tetrazolium-based MTT method and VEGF expression in tumor cells was evaluated by flow cytometry. COX-2-induced VEGF expression in tumor cells was monitored after treatment with inhibitors of protein kinase C PKC PKA prostaglandin E2 PGE2 and an activator of PKC. Results COX-2 over-expression correlated with MVD P and VEGF expression P in NSCLC samples and multivariate analysis demonstrated an association of VEGF with COX-2 expression P . Exogenously applied COX-2 stimulated the growth of NSCLCs exhibiting EC50 values of X 10-3 X 10-3 and X 10-3 gM in A549 H460 and A431 cells respectively COX-2 treatment also enhanced tumor-associated VEGF expression with similar potency. Inhibitors of PKC and PGE2 attenuated COX-2-induced VEGF expression in NLCSCs whereas a PKC activator exerted a potentiating effect. Conclusion COX-2 may contribute to VEGF expression in NSCLC. PKC and .