根據(jù)威克森林大學(xué)醫(yī)學(xué)院 (Wake Forest University School of Medicine)的一項研究結(jié)果發(fā)現(xiàn),，原本用來調(diào)控血壓的一個荷爾蒙分子,，居然可以在小鼠肺癌的實驗動物模型中，發(fā)現(xiàn)抑制腫瘤生長的效果,。
據(jù)該研究團隊發(fā)表在最新一期癌癥研究 (Cancer Research)的論文顯示,，這次研究人員發(fā)現(xiàn)具有抑癌效果的分子，就是稱為 angiotensin-(1-7)血壓調(diào)控荷爾蒙,，就過去的數(shù)據(jù)顯示 angiotensin-(1-7)這個荷爾蒙發(fā)現(xiàn)于 1988年,，它是身體里控制血壓的關(guān)鍵分子，血管壁會因為此一荷爾蒙的作用,，因而放松進而擴大管徑,，血管中的壓力自然會因此而舒緩下來。
這次研究人員確定 angiotensin-(1-7)血壓調(diào)控荷爾蒙的施用,，可以使小鼠肺部的腫瘤體積,，至少縮小 30%以上，而沒有施用血壓調(diào)控荷爾蒙的小鼠,，肺部的腫瘤尺寸，足足放大了一倍,。
雖然研究人員至今還不能完全掌握這個抑癌作用的機制,，但這個新發(fā)現(xiàn)的線索，很可能在未來,，成為每年全美地區(qū)十七萬新增肺癌病患的希望,。
(資料來源 : Bio.com)
部分英文原文：
Experimental Therapeutics, Molecular Targets, and Chemical Biology
Angiotensin-(1-7) Inhibits Growth of Human Lung Adenocarcinoma Xenografts in Nude Mice through a Reduction in Cyclooxygenase-2
Jyotsana Menon1,2, David R. Soto-Pantoja1, Michael F. Callahan2, J. Mark Cline3, Carlos M. Ferrario1,2, E. Ann Tallant1,2 and Patricia E. Gallagher1,2
1 Hypertension and Vascular Research Center and Departments of 2 Physiology and Pharmacology and 3 Pathology, Wake Forest University School of Medicine, Winston-Salem, North Carolina
Requests for reprints: Patricia E. Gallagher, The Hypertension and Vascular Research Center, Wake Forest University School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157-1032. Phone: 336-716-4455; Fax: 336-716-2456; E-mail: [email protected] .
Angiotensin-(1-7) [Ang-(1-7)] is an endogenous peptide of the renin-angiotensin system with vasodilator and antiproliferative properties. Our previous studies showed that Ang-(1-7) reduced serum-stimulated growth of human lung cancer cells in vitro through activation of a unique AT(1-7) receptor. The current study investigates the effect of Ang-(1-7) on lung tumor growth in vivo, using a human lung tumor xenograft model. Athymic mice with tumors resulting from injection of A549 human lung cancer cells were treated for 28 days with either i.v. saline or Ang-(1-7), delivered by implanted osmotic mini-pumps. Treatment with Ang-(1-7) reduced tumor volume by 30% compared with the size before treatment; in contrast, tumor size in the saline-treated animals increased 2.5-fold. These results correlate with a reduction in the proliferation marker Ki67 in the Ang-(1-7)–infused tumors when compared with the saline-infused tumor tissues. Treatment with Ang-(1-7) significantly reduced cyclooxygenase-2 (COX-2) mRNA and protein in tumors of Ang-(1-7)–infused mice when compared with mice treated with saline as well as in the parent A549 human lung cancer cells in tissue culture. These results suggest that Ang-(1-7) may decrease COX-2 activity and proinflammatory prostaglandins to inhibit lung tumor growth. In contrast, the heptapeptide had no effect on COX-1 mRNA in xenograft tumors or A549 cells. Because Ang-(1-7), a peptide with antithrombotic properties, reduces growth through activation of a selective AT(1-7) receptor, our results suggest that the heptapeptide represents a novel treatment for lung cancer by reducing COX-2. [Cancer Res 2007; 67(6):2809–15]
