strychnine and Lung-Neoplasms

It has been proven that Cyclin D1 and Cyclin E are the important positive regulators of cell cycle, they are closely related to the tumor proliferation. The aim of this study is to explore the relationship between Brucine and the proliferation in human lung cancer cell line PC-9, and the effect of it on the expression of Cyclin D1 and Cyclin E.. PC-9 cells were divided to 4 groups: the normal control group, the DMSO control group (2‰), the 150 μM Brucine group, and the 300 μM Brucine group. The proliferation rate of PC-9 cells was determined by The CellTiter-Glo Luminescent Cell Viability Assay and Colony Formation assay. The change of cell cycle was detected by Flow cytome try. Expressions of cell cycle regulators Cyclin D1, Cyclin E mRNA were determined by qRT-PCR. Protein expression of cell cycle regulators Cyclin D1, Cyclin E were determined by Western blot.. Compared with the control, Brucine remarkably inhibited the proliferation of PC-9 cells in a dose- and time-dependent manner (P<0.01); Flow cytome try showed that Brucine blocked the cell cycle of PC-9 cells at G0/G1, and the differences were statistically significant (P<0.01); qRT-PCR showed that the expression of Cyclin D1, Cyclin E mRNA were down-regulated; Western blot showed that the protein expression of Cyclin D1, Cyclin E were down-regulated.. Brucine can inhibit the proliferation of human lung cancer cell line PC-9 mainly by blocking the cell cycle at G0/G1 via down-regulating the expression of Cyclin D1, Cyclin E.. 背景与目的 已有的研究表明：Cyclin D1和Cyclin E是细胞周期中重要的正性调控因子，其高表达与肿瘤的增殖密切相关。本研究旨在探讨马钱子碱（Brucine）对人肺癌细胞株PC-9增殖的影响，及其与Cyclin D1和Cyclin E表达的影响。方法 将PC-9细胞分为4组：空白对照组、DMSO对照组（2‰）、150 μM Brucine组、300 μM Brucine组。CellTiter-Glo发光法、平板克隆形成实验观察该药对PC-9细胞增殖的影响，流式细胞仪检测细胞周期，qRT-PCR检测细胞周期相关基因Cyclin D1、Cyclin E mRNA的表达，Western blot检测细胞周期相关基因Cyclin D1、Cyclin E蛋白的表达。结果 与对照组比较，CellTiter-Glo发光法、平板克隆形成实验结果显示：Brucine可以抑制人肺癌细胞株PC-9的增殖，并呈时间-剂量依赖性（P<0.01）；流式结果显示对细胞周期的影响主要是阻滞PC-9细胞于G0/G1期；qRT-PCR结果显示Cyclin D1、Cyclin E mRNA的表达下调；Western blot结果显示Brucine使Cyclin D1、Cyclin E的表达降低。结论 Brucine能明显抑制人肺癌细胞株PC-9的增殖，机制主要与其通过下调Cyclin D1、Cyclin E表达，进而阻滞细胞周期有关。

Topics: Cell Cycle Checkpoints; Cell Line, Tumor; Cell Proliferation; Cell Survival; Cyclin D1; Cyclin E; Down-Regulation; Drugs, Chinese Herbal; Gene Expression Regulation, Neoplastic; Growth Inhibitors; Humans; Lung Neoplasms; Strychnine

Brucine is an alkaloid derived from the seeds of Strychnos nux-vomica Linn. which have long been used as a traditional medicine for the treatment of hepatocellular carcinoma (HCC) in China. HCC prognosis can be greatly influenced by metastasis. There has thus far been little research into brucine as a source of anti-metastasis activity against HCC. In this study, we revealed that brucine dramatically repressed HepG2 and SMMC-7721 HCC cell migration with few cytotoxic effects. Hypoxia inducible factor 1 (HIF-1) is a key transcription factor mediating cell migration and invasion. Brucine suppressed HIF-1-dependent luciferase activity in HepG2 cells. The transcriptions of four known HIF-1 target genes involved in HCC metastasis, i.e., fibronectin, matrix metallopeptidase 2, lysyl oxidase, and cathepsin D, were also attenuated after brucine treatment. Experiments in vivo showed that an intraperitoneal injection of 5 and 15 mg/kg of brucine resulted in dose-dependent decreases in the lung metastasis of H22 ascitic hepatoma cells. Moreover, a dosage of brucine at 15 mg/kg exhibited very low toxic effects to tumor-bearing mice. Consistently, brucine downregulated expression levels of HIF-1 responsive genes in vivo. Our current study demonstrated the capacity of brucine in suppressing HCC cell migration in vitro and lung metastasis in vivo. The inhibition of the HIF-1 pathway is implicated in the anti-metastasis activity of brucine.

Topics: Animals; Animals, Outbred Strains; Antineoplastic Agents, Phytogenic; Carcinoma, Hepatocellular; Cell Line, Tumor; Cell Movement; China; Dose-Response Relationship, Drug; Ethnopharmacology; Gene Expression Regulation, Neoplastic; Humans; Hypoxia-Inducible Factor 1; Liver Neoplasms; Lung Neoplasms; Male; Mice; Neoplasm Proteins; Random Allocation; Seeds; Strychnine; Strychnos nux-vomica; Xenograft Model Antitumor Assays

Isostrychnopentamine (ISP) is an indolomonoter-penic alkaloid that is present in the leaves of Strychnos usambarensis, an East African small tree. We have reported previously pro-apoptotic effects induced in vitro by ISP in the human HCT-116 colon cancer cell line, a model that displays relative sensitivity to apoptosis. In the present study, we observed that the in vitro growth inhibitory activities of ISP are similar in cancer cells that display sensitivity versus resistance to apoptosis. We made use of the U373 glioblastoma and the A549 non-small cell lung cancer (NSCLC) cell lines as models relatively resistant to apoptosis, and the human PC-3 prostate cancer cell line as a model relatively sensitive to apoptosis. While ISP induced transient decreases in [ATP]i and apoptosis in human U373 GBM cells, it did not provoke such features in A549 NSCLC cells. It thus seems that ISP-induced anti-cancer activity can lead to pro-apoptotic effects as a consequence, while apoptosis seems not to be the main cause by which ISP induces cancer cell death. ISP is a compound that merits further investigations in order to: i) identify the mechanism(s) of action by which it kills cancer cells, and ii) hemisynthesize novel ISP derivatives aiming to overcome, at least partly, the resistance of metastatic cancers to apoptosis.

Topics: Adenosine Triphosphate; Antineoplastic Agents, Phytogenic; Apoptosis; Brain Neoplasms; Breast Neoplasms; Carbolines; Carcinoma, Non-Small-Cell Lung; Cell Line, Tumor; Cell Proliferation; Dose-Response Relationship, Drug; Drug Resistance, Neoplasm; Female; Glioblastoma; Humans; Inhibitory Concentration 50; Lung Neoplasms; Male; Neoplasms; Plant Leaves; Prostatic Neoplasms; Strychnos; Time Factors