2013-08-012024-05-13https://scholars.lib.ntu.edu.tw/handle/123456789/648627摘要：帶有 t(4;11) MLL-AF4 或 t(9;22)染色體轉位之急性淋巴性白血病(ALL) 為高危險群白血病(VHR-ALL)；病人即使接受密集高劑量化療仍難以控制惡化與死亡。在 t(9;22)費城染色體 Ph+ -ALL 以酪酸激酶抑制劑搭配化療雖可延長病人無病存活，但 ABL 激酶突變/擴增及繼發的細胞變異皆使 Ph+-ALL 對治療產生抗性，病程惡性發展並難以治療。發展新的治療標的尤有助於 VHR-ALL 的治療。 許多癌症細胞因細胞凋亡機制異常，可逃脫於以誘發凋亡為基礎設計的治療。近來研究顯示在癌症治療過程中發生若干不需 caspase 參與、不同於典型細胞凋亡的計劃性細胞死亡方式：包括節制(計劃)性細胞壞死，溶小體膜通透媒介性死亡，細胞自噬關聯性死亡，組成互相作用的抑癌網路。尤其，細胞壞死亦可在細胞中以特定訊息傳導路徑調控秩序性的發生，是為節制(計劃)性的細胞壞死。 HQ17(3)為萃取自天然漆液之對苯二酚衍生物，具有拓蹼酶毒素特性，可抑殺多種腫瘤細胞株。吾人於先驅實驗中發現低濃度的 HQ17(3)即可對多種 ALL 細胞株發揮毒殺作用，但對正常週邊血液白血球並無毒性。HQ17(3)在 RS4;11[t(4;11)]與 Sup-B15 [t(9;22), Ph+ ]ALL 細胞株皆可快速誘發細胞膜破壞、DNA 斷裂、粒線體膜電位喪失及不依賴 caspase 活性的細胞死亡，且各種破壞皆與 HQ17(3)誘發之氧化壓力相關。 有鑑於 HQ17(3)對 VHR-ALL 細胞的強力抑殺效果，並誘發具有非傳統細胞凋亡的細胞死亡模式；可以提供在 ALL 細胞誘發他類細胞死亡路徑的絶佳研究平台，並可用於探索新的VHR-ALL 治療標的，有助開發有效但較低毒性的 VHR-ALL 輔助治療方法。爰此，吾人提出二年期研究計劃，目標有四： 1.分析並了解HQ17(3)在VHR-ALL RS4;11及Sup-B15細胞中所誘發之各項細胞損害及死亡特徵。 2.探討執行 HQ17(3)引起 VHR-ALL 細胞毒殺的分子機轉，側重於 a.溶小體膜通透媒介性死亡。 b.與 RIP 激酶相關之節制性細胞壞死。 3.分析細胞自噬作用是否涉入 HQ17(3)誘發之 VHR-ALL 細胞死亡?是否影響 VHR-ALL 細胞長期群落形成能力? 4.在受 HQ17(3)改變的細胞傳訊途徑中探尋可能做為 VHR-ALL 治療的標的。<br> Abstract: Acute lymphoblastic leukemias (ALLs) harboring t(4;11) MLL-AF4 or t(9;22) BCR-ABL genetic abnormality are classified very high risk (VHR) ALLs. Patients suffered from VHR-ALLs display poor clinical outcome irrespective of intensive chemotherapies. Incorporation of tyrosine kinase inhibitor with chemotherapies has improved the survival of patients with t(9;22) Philadelphia(Ph+) chromosome -ALL. However, ABL kinase mutation/amplification and BCR-ABL-independent signaling after secondary transformation make a very aggressive course and challenge in treatment of Ph+-ALL. Development of new therapeutics will provide great value in treatment of VHR-ALLs. Many cancer cells bear defective apoptotic components and evade from pharmacological induction of apoptosis. Recently, several caspase-independent (non-classical) programmed cell death patterns, including controlled (programmed) necrosis, lysosomal membrane pearmeability (LMP)-mediated cell death, and death associated with autophagy are found to form an intricate effector network in therapy-induced cytotoxicity. Of note, controlled (programmed) necrosis emerged as a well controlled form of cell demise trigger by death receptor/Toll-like receptor signaling and genotoxic stress. HQ17(3)[10’(Z),13’(E), 5’(E)-heptadecatrienyl hydroquinone] isolated from sap has shown a topoisomerase II poison and anti-cancer activity. We found HQ17(3) exerts potent cytotoxicity to several ALL cell lines at micromolar concentration but is non-toxic to normal peripheral blood leukocytes. HQ17(3) induces rapid caspase-independent cell death in VH-ALL cell lines RS4;11[with t(4;11)] and Sup-B15 [with t(9;22), Ph+ ]. The cell death is characterized by loss of membrane integrity, DNA fragmentation, mitochondrial membrane potential disturbance, all of which are associated with oxidative stress induced by HQ17(3). The highly effective cytotoxicity and unique pattern of cell death induced by HQ17(3) provide an excellent platform for exploring alternative pathways to induce cell death in ALL cells, and searching for potential therapeutic candidate to design more effective but less toxic therapy for VHR-ALLs. Thus, we propose a two-year project with 4 specific aims. 1. To characterize the pattern of cytotoxicity induced by HQ17(3) in very VHR-ALL cells (RS4;11 and SUP-B15). 2. To investigate the molecular mechanism implicated in the execution of HQ17(3)-induced cytotoxicity in VHR ALL cells-focus on (a) LMP-mediated, and (b) RIP1 kinase-associated controlled cell death. 3. To access whether autophagy is involved in HQ17(3)-induced cytotoxic process and if it influence the long-term clonogenic activity in the VHR-ALL cells. 4. Exploring potential therapeutic targets among the elements of signaling pathways altered by HQ17(3) treatment.急性淋巴性白血病(ALL)節制(計劃)性細胞壞死溶小體膜通透(LMP)烷基對苯二酚衍生 物 HQ17(3)acute lymphoblast leukemia (ALL)controlled (programmed) necrosislysosomal membrane permeability (LMP)alkyl hydroquinone HQ17(3)