Anti-leukemic properties of aplysinopsin derivative EE-84 alone and in combination with BH3 mimetic A-1210477

Abstract

Aplysinopsins are a class of marine indole alkaloids that exhibit a wide range of biological activities such as prevention of neoplastic growth on an array of different cancer cell lines. Although both the indole and N-benzyl moieties of aplysinopsins are known to possess anti-proliferative activity against cancer cells, their mechanism of action remains unclear. Through in vitro and in vivo proliferation and viability screening of newly synthesized aplysinopsin analogs on myelogenous leukemia cell lines and zebrafish toxicity tests as well as analysis of differential toxicity in non-cancerous RPMI 1788 cells, EE-84 was identified as a promising novel drug candidate against myeloid leukemia. This indole derivative demonstrated drug-likeness in agreement with Lipinskis rule of five and was responsible for cell cycle dysregulation in K562 cells in line with its cytostatic effect. EE-84-treated K562 cells likewise underwent morphological changes suggesting mitochondrial dysfunction. Finally, the synergistic cytotoxic effect of EE-84 with a BH3 mimetic, the Mcl-1 inhibitor, A-1210477, against K562 cells was demonstrated, highlighting the inhibition of anti-apoptotic Bcl-2 proteins as a promising therapeutic approach against myeloid leukemia in combination with EE-84.

Aplysinopsin은 항암 효과와 같은 다양한 생물학적 활성을 나타내는 해양 인돌 알카로이드 계열의 천연화합물이다. Indole 및 N-benzyl moiety를 가진 aplysinopsin과 그의 유사체들은 암 세포에 대한 항 증식 활성을 갖는 것으로 알려졌지만, 이들의 작용 메커니즘은 아직 불명확하다. In vitro 독성 시험 - cell proliferation과 cell viability 분석 및 colony formation assay – 그리고 in vivo zebrafish toxicity test를 통해 백혈병 세포주에서의 aplysinopsin 화합물 치료 가능성을 확인한 결과, EE-84는 잠재적인 drug lead인 것을 나타냈다. EE-84은 Lipinski의 rule of five에 따라 약물 유사성을 보여주었고 이 인돌 유사체는 K562 세포에서 cell cycle dysfunction을 유도하였다. EE-84가 처리된 K562 세포들도 마찬가지로 형태변화를 겪는데 이는 시간 경과에 따른 cellular 스트레스를 암시한다. 결과적으로 본 연구에서 BH3 모방체와 함께 EE-84의 세포사멸 동반상승효과를 보였으며, K562 성장에 반하는 Mcl-1 억제제는 백혈병에 관해 유망한 치료적 접근으로서 anti-apoptotic machinery의 억제를 강조하였다.