Naphtho[1,2-b]furan-4,5-dione誘導人類口腔癌細胞株Ca9-22凋亡機制之研究

Apoptotic mechanism of Naphtho[1,2-b]furan-4,5-dione in human oral carcinoma Ca9-22 cells.

莊珮彣(Pei-Wen Chuang)

指導教授 ： 林信仁

高雄醫學大學/生命科學院/醫藥暨應用化學研究所/碩士(2010年)

摘要

Naphtho[1,2- b]furan-4,5-dione (NFD)可經由chloroacetaldehyde與2-hydroxy-1,4-naphthoquinone 一鍋合成反應而成，先前的研究發現具備些許的抗癌活性。然而，抑制癌細胞增生的分子機制尚未被探討。本研究以流式細胞儀分析經NFD處理之人類口腔癌細胞株(Ca9-22 cells)，結果顯示細胞週期停滯在G2/M期，進一部探討細胞週期蛋白質的變化，發現cyclin A、CDK1 以及CDK2都有減少的趨勢，及扮演細胞週期抑制者的p27增加。本研究亦發現NFD誘導凋亡使得促進細胞凋亡蛋白Bax、Bad增加，抗細胞凋亡蛋白Bcl-XL、Bcl-2、Mcl-1、XIAP降低，造成cytochrome c的釋出以及capsase-9、capsase-3的活化。

進一步的探討其訊息傳遞，發現NFD會抑制Src的磷酸化及其下游的PI3K和Akt的活化，Ca9-22細胞同時處理NFD與PP2(Src專一性抑制劑)會發現更明顯的細胞週期停滯現象與細胞凋亡的產生。綜合以上實驗結果顯示NFD會抑制人類口腔癌細胞株(Ca9-22)細胞週期停滯於G2/M期，並有誘導細胞凋亡的現象；NFD會抑制細胞增生是經由抑制Src的磷酸化及其下游的PI3K和Akt路徑。所以NFD是一具有潛力抑制人類口腔癌細胞株(Ca9-22)的化合物。

關鍵字

細胞週期 ； 細胞凋亡 ； 訊息傳遞

並列摘要

Naphtho[1,2-b]furan-4,5-dione(NFD),prepared from 2-hydroxy-1,4
-naphthoquinone and chloroacetaldehyde in an efficient one-pot reaction, exhibits anti-carcinogenic effects. However, the molecular mechanisms on the anti-proliferative activity in cancer cells have been poorly elucidated. NFD exerted anti-proliferative activity with the G2/M cell cycle arrest and apoptosis in Ca9-22 cells. The NFD-induced cell cycle arrest was correlated with a marked decrease in the expression levels of cyclin A, and their activating partner cyclin-dependent kinases (CDK) 1and 2 with concomitant induction of p27. NFD-induced apoptosis was accompanied with up-regulation of Bax and Bad, and down-regulation of Bcl-2, Bcl-XL, Mcl-1, and X-linked inhibitor of apoptosis (XIAP), resulting in cytochrome c release and sequential activation of caspase-9 and caspase-3.

In the analysis of signal transduction pathway, NFD substantially reduced the phosphorylation of Src and activation of phosphatidylinositol 3-kinase (PI3K) and Akt. The combined treatment of NFD with PP2 (a specific Src inhibitor) significantly enhanced the cell cycle arrest and apoptosis in Ca9-22 cells. These findings suggest that NFD-mediated cytotoxicity of Ca9-22 cells related with the G2/M cell cycle arrest and apoptosis via inactivation of Src and PI3K/Akt-mediated signaling pathways. Thus, NFD appears to be a potential therapeutic agent for killing Ca9-22 cells.

並列關鍵字

cell cycle ； apoptosis ； singal transduction ； Naphtho[1,2-b]furan-4,5-dione

參考文獻

行政院衛生署死因統計統計表：http://www.doh.gov.tw.

Adams, J.M., Cory S., 1998. The Bcl-2 protein family: arbiters of cell survival. Science 281, 1322-1326.

Agami, R., Bernards, R., 2000. Distinct initiation and maintenance mechanisms cooperate to induce G1 cell cycle arrest in response to DNA damage. Cell 102, 55-66.

Alnemri, E.S., Lvingston, D.J., Nicholson, D.W., Salvesen, G., Thornberry, N.A., Wong, W.W., Yuan, J., 1996. Human ICE/CED-3 protease nomenclature. Cell 87, 171.

Antonsson, B., Martinou, J.C., 2000. The Bcl-2 protein family. Exp Cell Res 256, 50-57.