新黃酮類化合物Protoapigenone對卵巢癌及前列腺癌的毒殺效果與機轉探討

The cytotoxic effect and molecular mechanism of new flavonoid compound, protoapigenone, against ovarian and prostate cancer cells.

張雪玲(Hsueh-Ling Chang)

指導教授 ： 吳永昌

共同指導教授 ： 袁行修(Shyng-Shiou F. Yuan)

高雄醫學大學/藥學院/天然藥物研究所/博士(2008年)

摘要

為了開發天然藥物於癌症治療上的應用，本實驗室由粗毛金星蕨的甲醇萃取物中，分離出新的黃酮類化合物protoapigenone。在細胞毒殺活性篩選結果中顯示出protoapigenone對人類卵巢癌細胞 (MDAH-2774, SKOV3)、子宮頸癌細胞株 (HeLa, C33A) 、乳癌細胞株 (T47D, MCF-7)及前列腺癌細胞株 (LNCap) 具有明顯的細胞毒殺效果。特別的是，protoapigenone對於正常人類乳腺細胞 (MCF-10A) 以及卵巢上皮細胞 (HOSE6-3, HOSE11-12) 的毒殺效果很低，這結果顯示protoapigenone可能對於抑制人類癌細胞具有選擇性。因此，我們進而探討protoapigenone對女性特有癌症“卵巢癌”及男性特有癌症“前列腺癌”的毒殺作用與機轉。
以protoapigenone對癌細胞的細胞週期以及細胞凋亡的影響為研究方向，由實驗結果得知protoapigenone對卵巢癌細胞以及前列腺癌細胞在作用的前期 (PS外翻的細胞/ Annexin-V/FITC positive cells) 或後期 (造成DNA斷裂的細胞/ TUNEL positive cells) 皆能顯著的引起癌細胞走向細胞凋亡之自殺死亡機制。所引起細胞凋亡的機制乃藉由調控BcL-2蛋白家族，進而活化caspase-3的活性，促使DNA修復蛋白Poly (ADP-ribose) polymerase (PARP) 切裂而無法進行DNA修復作用。另一方面，protoapigenone也藉由影響CDK2、Cyclin B1、Cdc25C蛋白活性表現，而將卵巢癌細胞以及前列腺癌細胞的細胞週期停滯於S及G2/M，因而抑制了癌細胞的不正常增生。在前列腺癌細胞中，研究成果證實p38 MAPK及JNK1/2的活性在protoapigenone對於前列腺癌細胞所引起的毒殺機制中佔著舉足輕重的角色。
進而於活體動物實驗結果中， 顯示protoapigenone在裸鼠動物實驗上確實能有效地抑制卵巢癌腫瘤以及前列腺癌腫瘤的生長。此有效的抑制腫瘤生長作用乃與protoapigenone能引起的細胞凋亡有關。分析裸鼠動物之血液生化值，得知protoapigenone對於治療後的活體動物之肝、腎及造血功能並沒有產生顯著性的不良副作用。
由研究的初步成果證實protoapigenone在in vitro及in vivo的實驗皆具有顯著且低毒性的抑制癌細胞生長效果，開啟了protoapigenone具有潛力成為一個抗卵巢癌及前列腺癌的化合物之發展性。目前的研究成果，已經申請台灣、美國以及歐、日等國之專利，以朝植物藥新藥開發為目標。

關鍵字

新黃酮類化合物 ； 卵巢癌 ； 前列腺癌

並列摘要

In order to develop the application of nature products on cancer therapy, we isolated a novel flavonoid, protoapigenone, from the methanol extract of Thelypteris torresiana (Gaud.) Alston (Thelypteridaceae). The cytotoxic results indicated that protoapigenone showed the significantly cytotoxic activities toward human ovarian cancer cell lines (MDAH-2774, SKOV3), human cervical cancer cell lines (HeLa, C33A), human breast cancer cell lines (T47D, MCF-7) and human prostate cancer cell line (LNCap). Compared the data with immortalized human breast cancer cell line (MCF-10A) and ovarian epithelial cell lines (HOSE6-3, HOSE11-12), it had less cytotoxic activity. These results suggested that protoapigenone has the selective cytotoxicity against human cancer cells. This drawn our interests to investigate the anti-cancer effect and molecular mechanism of protoapigenone on ovarian cancer cells and prostate cancer cells.
The aim of this study is detecting the effect of protoapigenone on cell cycle progression and apoptotic induction in cancer cells. The results showed that protoapigenone significantly induced cancer cells go through apoptosis in early (Annexin-V/FITC positive cells) and late period (TUNEL positive cells). Protoapigenone regulated the BcL-2 family, and then induced caspase-3 activity which cleaved the DAN repair protein Poly (ADP-ribose) polymerase (PARP). On the other hand, protoapigenone also arrested cancer cells at S and G2/M phases by regulating the activation and expression of CDK2, Cyclin B1 and Cdc25C on ovarian and prostate cancer cells. In prostate cancer, the activity of p38 MAPK and JNK1/2 play the critical roles in protoapigenone-induced cell death.
In vivo study, the results showed that protoapigenone suppressed the growth of ovarian and prostate cancer cells without significant hepatotoxicity, nephrotoxicity and hematological toxicity. Protoapigenone actually induced cancer cells go through apoptosis in protoapigenone-treated tumors.
Our results first indicated that protoapigenone may be developed a promising chemotherapeutic agent for ovarian or prostate cancer in the future. The results of our research have filed Taiwan、US、Japan and Europe patent to develop as new botanical drugs.

並列關鍵字

Protoapigenone ； ovarian cancer ； prostate cancer

參考文獻

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