Mohammad R M, Diwakaran H, Maki A, Emara M A, Pettit G R, Redman B, al-Katib A
Department of Internal Medicine, Wayne State University, Detroit, MI 48201, USA.
Leuk Res. 1995 Sep;19(9):667-73. doi: 10.1016/0145-2126(95)00037-o.
Bryostatin 1 (Bryo1), a macrocyclic lactone and a protein kinase C activator, is isolated from the marine bryozoan Bugula neritina. In this study we describe its effect, alone or after sequential use with vincristine (VCR), on the human diffuse large cell lymphoma cell line WSU-DLCL2. Our results show that both Bryo1 and VCR induced apoptosis as demonstrated by morphological examination, DNA flow cytometry (FCM), and DNA fragmentation on agarose gel electrophoresis. Cells pretreated for 24 h with Bryo1 and then exposed to VCR showed an increase in apoptosis compared to cells that were exposed to Bryo1 or VCR alone. We also studied the effects of Bryo1, VCR and their combination on cell growth, bcl-2 and p53 expression, and inhibition of cell proliferation as measured by [3H]-thymidine incorporation. Cell analysis showed significant growth inhibition of WSU-DLCL2 cells by the Bryo1/VCR combination as compared to either agent alone. Immunocytochemistry (ICC) revealed that relative bcl-2 oncoprotein expression was decreased in cells treated with Bryo1, or VCR separately and was abolished by combining both drugs. When examined by ICC, WSU-DLCL2 cells were initially negative for the p53 protein. However, upon treatment with the above agents, the relative expression of p53 was moderate on Bryo1-or VCR-treated cells and strong on cells treated with the Bryo1/VCR combination. Cell proliferation as measured by [3H]-thymidine incorporation revealed significant inhibition of tumor growth by exposure to the agents when compared to the control. In contrast, Bryo1, VCR and their combination did not show any inhibition of normal bone marrow growth. These findings taken together, suggest that the exposure of WSU-DLCL2 cells to Bryo1 prior to treatment with VCR enhances apoptosis, a phenomenon which might be exploited for future therapies.
苔藓抑素1（Bryo1）是一种大环内酯类化合物，也是一种蛋白激酶C激活剂，它是从海洋苔藓虫类的美丽琥珀苔虫中分离出来的。在本研究中，我们描述了它单独使用或与长春新碱（VCR）序贯使用时，对人弥漫性大细胞淋巴瘤细胞系WSU-DLCL2的影响。我们的结果表明，Bryo1和VCR均可诱导细胞凋亡，这通过形态学检查、DNA流式细胞术（FCM）以及琼脂糖凝胶电泳上的DNA片段化得以证实。与单独暴露于Bryo1或VCR的细胞相比，先用Bryo1预处理24小时然后再暴露于VCR的细胞凋亡增加。我们还研究了Bryo1、VCR及其组合对细胞生长、bcl-2和p53表达的影响，以及通过[3H]-胸腺嘧啶核苷掺入法测定的细胞增殖抑制情况。细胞分析表明，与单独使用任何一种药物相比，Bryo1/VCR组合对WSU-DLCL2细胞具有显著的生长抑制作用。免疫细胞化学（ICC）显示，单独用Bryo1或VCR处理的细胞中，相对bcl-2癌蛋白表达降低，而两种药物联合使用则使其表达消失。通过ICC检测时，WSU-DLCL2细胞最初p53蛋白呈阴性。然而，在用上述药物处理后，Bryo1或VCR处理的细胞中p53的相对表达中等，而Bryo1/VCR组合处理的细胞中p53的相对表达较强。通过[3H]-胸腺嘧啶核苷掺入法测定的细胞增殖显示，与对照组相比，暴露于这些药物可显著抑制肿瘤生长。相反，Bryo1、VCR及其组合对正常骨髓生长没有任何抑制作用。综合这些发现表明，在使用VCR治疗之前，将WSU-DLCL2细胞暴露于Bryo1可增强细胞凋亡，这一现象可能在未来的治疗中得到利用。
