Screening of Promising Chemotherapeutic Candidates from Plants against Human Adult T-Cell Leukemia/Lymphoma (VII): Active Principles from Thuja occidentalis L.

During the screening of novel chemotherapeutic candidates from plants against adult T-cell leukemia/lymphoma, we identified that the extracts of Thuja occidentalis (Cupressaceae) showed potent anti-proliferative activity in MT-1 and MT-2 cells. Therefore, we attempted to isolate the active components from this plant. We isolated and identified 32 compounds (1–32; eight lignans, 18 terpenoids, and six flavonoids) from the extracts of the leaves and cones. Their structures were determined by spectroscopic analysis. Several of the isolated compounds inhibited the growth of both cell lines. Lignans showed more potent activity than other classes of compounds. A comparison of the activities of compounds 1–8 revealed that the presence of a trans-lactone (linkage of C-6 to C-7) correlated with increased activity. Diterpenes showed moderate activity, and the presence of a ketone moiety at the C-7 position correlated with increased activity in compounds 12–21. In addition, biflavones showed moderate activity, and the presence of methoxy functions appeared to influence the activity of these compounds. Several lignans were lead compound of anti-cancer reagent (etoposide). In conclusion, not only lignans, but also diterpenes and/or biflavones, may be promising candidates for the treatment of adult T-cell leukemia/lymphoma.     

白血病G6PD蛋白表达的研究

目的:观察白血病患者骨髓中白血病细胞葡萄糖-6磷酸脱氢酶(G6PD)蛋白的表达情况,探讨G6PD与白血病的关系。方法:应用免疫组化方法检测35例白血病患者和35例非恶性血液病患者骨髓组织标本中白血病细胞G6PD蛋白的表达,比较白血病患者和非恶性血液病患者G6PD蛋白表达率的差异。结果:G6PD蛋白在白血病骨髓组织白血病细胞中呈现弱阳性表达。35例白血病患者骨髓组织中G6PD蛋白阳性表达率为25.7%(9/35),而35例非恶性血液病患者骨髓组织中G6PD蛋白阳性表达率为2.9%(1/35),差异有统计学意义(P<0.05)。结论:白血病可能存在G6PD蛋白的表达上调,值得进一步研究。     

Investigation into omacetaxine solution stability for in vitro study

Omacetaxine is a natural product extract originating from Chinese medicine and finding therapeutic use as a potent myelosuppressive agent in leukemia. When planning in vitro cell biology experiments to assess omacetaxine activity against primary leukemic stem cells, it became apparent that the literature rarely describes the in vitro stability of the molecule, although accessible chromatographic methods have been published. Clearly whole organisms vs their component cells will differ in the way in which they handle xenobiotics, with the latter more dependent on physiochemical parameters such as pH and temperature in the absence of active metabolism or excretion. This could impact on the cells' experience of drug in culture. We therefore report here on examination of a modified, high‐performance liquid chromatography (HPLC) method with assessment of degradant production from a 72 h solution stability study, clearly demonstrating that omacetaxine is highly stable in representative cell culture conditions (37 °C, neutral pH) and persists for many days in marked contrast to its short‐half life in vivo. Copyright © 2011 John Wiley & Sons, Ltd.     

敏感和抗性的白血病HL60细胞对staurosporine诱导凋亡的不同反应(英)

用对蛋白激酶具有强烈抑制、作用广泛的抑制剂staurosporine（Sta）,研究敏感和抗三尖杉酯碱的人白血病HL60细胞中凋亡和多药抗药性的关系．Sta均能诱导2种细胞发生典型的凋亡,但抗性细胞发生凋亡需更长的时间,凋亡的细胞数减少．Sta增加柔红霉素在抗性细胞内的积聚,说明其能逆转多药抗药性．在抗性细胞凋亡过程中,mdrl基因表达没有变化,c-myc基因表达稍有增加．结果显示：Sta能诱导敏感和抗三尖杉酯碱的HL60细胞发生凋亡,mdrl基因表达与凋亡过程无关．     

Antitumor Activity and Mechanism of Action of the Antimicrobial Peptide AMP-17 on Human Leukemia K562 Cells

Cancer is one of the most common malignant diseases in the world. Hence, there is an urgent need to search for novel drugs with antitumor activity against cancer cells. AMP-17, a natural antimicrobial peptide derived from Musca domestica, has antimicrobial activity against Gram-positive bacteria, Gram-negative bacteria, and fungi. However, its antitumor activity and potential mechanism of action in cancer cells remain unclear. In this study, we focused on evaluating the in vitro antitumor activity and mechanism of AMP-17 on leukemic K562 cells. The results showed that AMP-17 exhibited anti-proliferative activity on K562 cells with an IC₅₀ value of 58.91 ± 3.57 μg/mL. The membrane integrity of K562 was disrupted and membrane permeability was increased after AMP-17 action. Further observation using SEM and TEM images showed that the cell structure of AMP-17-treated cells was disrupted, with depressions and pore-like breaks on the cell surface, and vacuolated vesicles in the cytoplasm. Furthermore, further mechanistic studies indicated that AMP-17 induced excessive production of reactive oxygen species and calcium ions release in K562 cells, which led to disturbance of mitochondrial membrane potential and blocked ATP synthesis, followed by activation of Caspase-3 to induce apoptosis. In conclusion, these results suggest that the antitumor activity of AMP-17 may be achieved by disrupting cell structure and inducing apoptosis. Therefore, AMP-17 is expected to be a novel potential agent candidate for leukemia treatment.     

Shikonin as a WT1 Inhibitor Promotes Promyeloid Leukemia Cell Differentiation

This study aims to observe the differentiating effect of shikonin on Wilms’ tumor 1 (WT1)-positive HL-60 cells and investigate the fate of the differentiated leukemia cells. WT1 overexpression unaffected cell viability but promoted resistance to H₂O₂-induced DNA injury and cell apoptosis. The binding of shikonin to the WT1 protein was confirmed by molecular docking and drug affinity reaction target stability (DARTS). Shikonin at the non-cytotoxic concentration could decrease the WT1 protein and simultaneously reduced the CD34 protein and increased the CD11b protein in a dose-dependent manner in normal HL-60 cells but not in WT1-overexpressed HL-60 cells. Shikonin unaffected HL-60 cell viability in 48 h. However, it lasted for 10 days; could attenuate cell proliferation, mitochondrial membrane potential (MMP), and self-renewal; prevent the cell cycle; promote cell apoptosis. In a mouse leukemia model, shikonin could decrease the WT1 protein to prevent leukemia development in a dose-dependent manner. In this study, we also confirmed preliminarily the protein–protein interactions between WT1 and CD34 in molecular docking and CO-IP assay. Our results suggest that: 1. shikonin can down-regulate the WT1 protein level for leukemia differentiation therapy, and 2. the interaction between WT1 and CD34 proteins may be responsible for granulocyte/monocyte immaturity in HL-60 cells.     

人体血液白细胞的显微光谱

采用显微光谱技术，得到了正常人及白血病患者的白细胞在可见光范围的光谱。结果显示，淋巴细胞和粒细胞的显微光谱各具特征，不同类型的白血病患者的淋巴细胞和粒细胞的显微光谱与正常人的相比也不同。结果不仅实现了白细胞的显微光谱学分类，而且可能为临床医学提供参考。     

新近发现的恶性肿瘤的染色体异常

作者报告一组新近发现的恶性肿瘤的染色体异常,均属少见的染色体变异.系采用淋巴结或骨髓直接法制备染色体标本.恶性淋巴瘤核型为14q~+t(2;14);慢性粒细胞白血病核型为pht(2;22).讨论了癌基因与染色体易位的关系.     

Pharmaceutical Drug Metformin and MCL1 Inhibitor S63845 Exhibit Anticancer Activity in Myeloid Leukemia Cells via Redox Remodeling

Metabolic landscape and sensitivity to apoptosis induction play a crucial role in acute myeloid leukemia (AML) resistance. Therefore, we investigated the effect of metformin, a medication that also acts as an inhibitor of oxidative phosphorylation (OXPHOS), and MCL-1 inhibitor {"type":"entrez-nucleotide","attrs":{"text":"S63845","term_id":"400540","term_text":"S63845"}}S63845 in AML cell lines NB4, KG1 and chemoresistant KG1A cells. The impact of compounds was evaluated using fluorescence-based metabolic flux analysis, assessment of mitochondrial Δψ and cellular ROS, trypan blue exclusion, Annexin V-PI and XTT tests for cell death and cytotoxicity estimations, also RT-qPCR and Western blot for gene and protein expression. Treatment with metformin resulted in significant downregulation of OXPHOS; however, increase in glycolysis was observed in NB4 and KG1A cells. In contrast, treatment with {"type":"entrez-nucleotide","attrs":{"text":"S63845","term_id":"400540","term_text":"S63845"}}S63845 slightly increased the rate of OXPHOS in KG1 and KG1A cells, although it profoundly diminished the rate of glycolysis. Generally, combined treatment had stronger inhibitory effects on cellular metabolism and ATP levels. Furthermore, results revealed that treatment with metformin, {"type":"entrez-nucleotide","attrs":{"text":"S63845","term_id":"400540","term_text":"S63845"}}S63845 and their combinations induced apoptosis in AML cells. In addition, level of apoptotic cell death correlated with cellular ROS induction, as well as with downregulation of tumor suppressor protein MYC. In summary, we show that modulation of redox-stress could have a potential anticancer activity in AML cells.     

Limitations of the Wittig-Horner-type annulation of fluorobutenolide moiety to 3-hydroxyquinoline-2,4(2H,3H)-diones. Novel modifications of the Perkow reaction including fluorinated acyloxy leaving groups

3-(Fluoroacyloxy)quinoline-2,4(1H,3H)-diones react with triethyl phosphite to afford either the product of the Perkow reaction or the corresponding 4-ethoxyquinolin-2(1H)-one. In both reactions, the fluorocarboxylate anion acts as the leaving group. For the corresponding 3-(fluoroiodoacetoxy) derivative this observation precludes the application of the intramolecular Wittig-Horner synthesis to modify quinoline-2,4(1H,3H)-diones by the annulation of a fluorinated but-2-enolide moiety.