黑將菌素 (Destruxin B) 對人類急性和慢性淋巴癌之抗癌機制探討
黑殭菌素 (Destruxin) 是由昆蟲寄生性真菌 (entomogenous fungi) 之一 (Matarhi
zium anisopliae) 所分泌出的毒素，在已分離出的三十餘種中，本研究中採用
的是由此一菌種分泌的二次代謝物 Destruxin B (DB) 作為抗腫瘤製劑。 DB 對
昆蟲具有毒性且運用在生物農藥已有數年之久。在之前的研究中發現到在體
外試驗或是活體試驗 DB 對於 DBA/2 老鼠 L5178Y 淋巴癌細胞有抑制的效果。
本論文將探討由黑殭菌素 B (Destruxin B) 對人類急性淋巴性白血病 Molt-4 和
人類非霍金氏淋巴癌 Toledo 細胞造成生長抑制或毒殺作用。由初期的實驗結
果得知 Molt-4 細胞在高於 5.05 uM DB 作用下可以有效的抑制癌細胞生長；
而 Toledo 細胞則在 1.26 uM DB 作用下明顯的抑制癌細胞生長。利用 Annexin
V 染色及 JC-1 染色的方式更進一步地證實出 Destruxin B 會引起 Molt-4 、 Tol
edo 細胞死亡是經由粒線體膜電位改變引起細胞凋亡，而非壞死。 Destruxin
B 作用在 Molt-4 和 Toledo 細胞 48 小時後，以西方點墨法的結果證實， AIF
和 Bax 蛋白表現有增加的情形， Bid 和 Bcl-2 蛋白表現量遞減，更能證實細
胞是經由粒線體膜電位改變引起細胞凋亡而死；並且也觀察到 FADD 、 caspa
se 8 、 caspase 3 的活化，發現 Destruxin B 可導致細胞經由死亡接受器途徑而
凋亡。綜合以上初步結果得知， Destruxin B 可以抑制人類急性淋巴性白血病
Molt-4 和人類非霍金氏淋巴癌 Toledo 細胞的生長，其機制是經由死亡接受器
途徑和粒線體途徑而使細胞走向凋亡。
Study the Mechanisms of Apoptosis of Destruxin B Anti-tumor Effect on
Human Acute and Chronic Lymphoma
Destruxins are second metabolic products form an entomogenous fungus, Mararhuzuim aniso
pliae. These substances are toxic to insect and have been used as an insecticide for decades. O
ver thirty analogues of destruxins have been isolated by different laboratories, the one used in
this study is Destruxin B (DB). The previous study in our laboratory revealed that DB has pote
nt anti-tumor activity in mouse L5178Y lymphoma cells in DBA/2 mice both in vitro and in vi
vo experiments. In this report, the Molt-4 human acute lymphoblastic leukemia cell line and th
e Toledo human non Hodgkin’s lymphoma cell lines was used as a subject to evaluate its anti-
tumor activity and study the mechanism of the effect. The initial experimental results showed t
hat DB possesses a potent growth suppression effect on Molt-4 when the doses of DB higher t
han 5.05 uM and Toledo obviously had suppression cell growth at 1.26 uM DB. Further Anne
xin V and JC-1 staining experimental results showed that Destruxin B caused Molt-4, Toledo
cell death by mitochondrial membrane potential changed to induce apoptosis. From the Weste
rn blot experimental results found that the expression of AIF and Bax was increased and that d
ecreased in Bid and Bcl-2 expression in Molt-4 and Toledo cells at 48 hours after DB treatmen
t, thus confirming cell death via mitochondrial membrane potential changed to induce apoptos
is. We also found the activation of FADD, caspase 8, caspase 3, thus confirming cell death ma
y via death receptor pathway to induce apoptosis also. In conclusion, the mechanisms of cell a
poptosis by DB treatment may be due to change mitochondrial membrane potential and the de
ath receptor pathway.
