ginsenoside-rg3 and Carcinoma--Lewis-Lung

Elevated production of reactive oxygen species (ROS) is observed in various cancer types and pathophysiological conditions. In cancer cells, ROS induce cell proliferation, genetic instability, and a malignant phenotype. Ginsenoside Rg3 is the main pharmacologically active component in ginseng and has been reported to have an antioxidant effect. To overcome lung cancer by regulating the ROS level, we investigated the antitumor effect and mechanism of Rg3 and its antioxidative property on Lewis lung carcinoma (LLC) cells.. Inhibition of ROS was suppressed in LLC cells by Rg3 treatment, and these cells were used to investigate the antioxidant, antiproliferative, and antitumor effects in LLC cells.. ROS production was increased in cells grown in serum-containing media (conditioned media) compared to those grown in serum-free media. The high level of ROS induced LLC cell proliferation, but treatment with Rg3 (200 ng/ml) resulted in reduction of ROS, leading to inhibition of cell proliferation. Treatment with Rg3 significantly reduced cyclin and cyclin-dependent kinase expression in LLC cells. Additionally, Rg3 treatment significantly suppressed activation of mitogen-activated protein kinases and induced LLC cell apoptosis through activation of pro-apoptotic proteins and suppression of anti-apoptotic proteins.. Taken together, these findings demonstrate the role of Rg3 in reduction of the intracellular ROS level, attenuation of proliferation via augmentation of cell cycle- and cell proliferation-associated proteins, and activation of apoptosis through regulation of apoptosis-associated proteins in LLC. These findings suggest that Rg3 could be used as a therapeutic agent in lung cancer.

Topics: Animals; Antioxidants; Apoptosis; Apoptosis Regulatory Proteins; Carcinoma, Lewis Lung; Cell Cycle; Cell Line, Tumor; Cell Proliferation; Cell Survival; Culture Media, Conditioned; Culture Media, Serum-Free; Flow Cytometry; Ginsenosides; Mice; Neoplasms; Reactive Oxygen Species

At present, it is elusive how non-small cell lung cancer (NSCLC) develops resistance to γ-radiation; however, the transcription factor nuclear factor-κB (NF-κB) and NF-κB-regulated gene products have been proposed as mediators. Ginsenoside Rg3 is a steroidal saponin, which was isolated from Panax ginseng. Ginsenoside Rg3 possesses high pharmacological activity and has previously been shown to suppress NF-κB activation in various types of tumor cell. Therefore, the present study aimed to determine whether Rg3 could suppress NF-κB activation in NSCLC cells and sensitize NSCLC to γ-radiation, using an NSCLC cell line and NSCLC xenograft. A clone formation assay and lung tumor xenograft experiment were used to assess the radiosensitizing effects of ginsenoside Rg3. NF-κB/inhibitor of NF-κB (IκB) modulation was ascertained using an electrophoretic mobility shift assay and western blot analysis. NF-κB-regulated gene products were monitored by western blot analysis. The present study demonstrated that ginsenoside Rg3 was able to sensitize A549 and H1299 lung carcinoma cells to γ-radiation and significantly enhance the efficacy of radiation therapy in C57BL/6 mice bearing a Lewis lung carcinoma cell xenograft tumor. Furthermore, ginsenoside Rg3 suppressed NF-κB activation, phosphorylation of IκB protein and expression of NF-κB-regulated gene products (cyclin D1, c-myc, B-cell lymphoma 2, cyclooxygenase-2, matrix metalloproteinase-9 and vascular endothelial growth factor), a number of which were induced by radiation therapy and mediate radioresistance. In conclusion, the results of the present study suggested that ginsenoside Rg3 may potentiate the antitumor effects of radiation therapy in NSCLC by suppressing NF-κB activity and NF-κB-regulated gene products, leading to the inhibition of tumor progression.

Topics: Animals; Apoptosis; Carcinoma, Lewis Lung; Carcinoma, Non-Small-Cell Lung; Cell Proliferation; Gamma Rays; Gene Expression Regulation, Neoplastic; Ginsenosides; Humans; Mice; NF-kappa B; Radiation-Sensitizing Agents; Xenograft Model Antitumor Assays

Accumulating evidence suggests that Ginsenoside Rg3 appears to inhibit tumor growth including Lewis lung carcinoma, intestinal adenocarcinomas or B16 melanoma by inhibiting cell proliferation, tumor cell invasion and metastasis. Endothelial progenitor cells (EPCs) appear to play a key role in the growth of early tumors by intervening with the angiogenic switch promoting tumor neovessel formation by producing angiogenic cytokines during tumor progression. This paper reports a novel mechanism of Ginsenoside Rg3, a candidate anticancer bio-molecule, on tumor angiogenesis by inhibiting the multiple bioactivities of EPCs. When Ginsenoside Rg3 was applied to the ex vivo cultured outgrowth ECs, a type of EPCs, it inhibited the cell proliferation, cell migration and tubular formation of EPCs. Importantly, Ginsenoside Rg3 attenuated the phosphorylation cascade of the VEGF dependent p38/ERK signaling in vitro. The xenograft tumor model clearly showed that Ginsenoside Rg3 suppresses tumor growth and tumor angiogenesis by inhibiting the mobilization of EPCs from the bone marrow microenvironment to the peripheral circulation and modulates VEGF-dependent tumor angiogenesis. In conclusion, this study provides a potential therapeutic molecule, Ginsenoside Rg3, as an anticancer drug by inhibiting the EPC bioactivities.

Topics: Angiogenesis Inhibitors; Animals; Apoptosis; Carcinoma, Lewis Lung; Cell Cycle; Cell Line, Tumor; Cell Movement; Cell Proliferation; Cell Survival; Cells, Cultured; Endothelial Cells; Gene Expression; Ginsenosides; Humans; Male; Mice; Mice, Inbred C57BL; Neovascularization, Pathologic; Stem Cells; Tumor Burden; Vascular Endothelial Growth Factor A; Vascular Endothelial Growth Factor Receptor-2; Xenograft Model Antitumor Assays

Ginsenoside Rg3, a saponin extracted from ginseng, inhibits angiogenesis. The combination of low-dose chemotherapy and anti-angiogenic inhibitors suppresses growth of experimental tumors more effectively than conventional therapy or anti-angiogenic agent alone. The present study was designed to evaluate the efficacy of low-dose gemcitabine combined with ginsenoside Rg3 on angiogenesis and growth of established Lewis lung carcinoma in mice.. C57L/6 mice implanted with Lewis lung carcinoma were randomized into the control, ginsenoside Rg3, gemcitabine and combination group. The quality of life and survival of mice were recorded. Tumor volume, inhibitive rate and necrosis rate were estimated. Necrosis of tumor and signals of blood flow as well as dynamic parameters of arterial blood flow in tumors such as peak systolic velocity (PSV) and resistive index (RI) were detected by color Doppler ultrasound. In addition, expression of vascular endothelial cell growth factor (VEGF) and CD31 were observed by immunohistochemstry, and microvessel density (MVD) of the tumor tissues was assessed by CD31 immunohistochemical analysis.. Quality of life of mice in the ginsenoside Rg3 and combination group were better than in the control and gemcitabine group. Combined therapy with ginsenoside Rg3 and gemcitabine not only enhanced efficacy on suppression of tumor growth and prolongation of the survival, but also increased necrosis rate of tumor significantly. In addition, the combination treatment could obviously decrease VEGF expression and MVD as well as signals of blood flow and PSV in tumors.. Ginsenoside Rg3 combined with gemcitabine may significantly inhibit angiogenesis and growth of lung cancer and improve survival and quality of life of tumor-bearing mice. The combination of chemotherapy and anti-angiogenic drugs may be an innovative and promising therapeutic strategy in the experimental treatment of human lung cancer.

Topics: Animals; Antineoplastic Combined Chemotherapy Protocols; Carcinoma, Lewis Lung; Cell Growth Processes; Deoxycytidine; Female; Gemcitabine; Ginsenosides; Humans; Lung Neoplasms; Mice; Mice, Inbred BALB C; Neovascularization, Pathologic; Random Allocation; Tumor Cells, Cultured; Vascular Endothelial Growth Factor A

Angiogenesis is now known to play an important role in both growth and metastasis of lung cancer. The intense interest in angiogenesis has led to a re-examination of the activity of many established cytotoxic agents. Some results of recent experimental studies have suggested that frequent administration of certain cytotoxic agents at low doses increases the antiangiogenic activity of the drugs. In the present study, we investigated the efficacy of the combination of low-dose cyclophosphamide and ginsenoside Rg3 for the antiangiogenic effect on Lewis lung carcinoma. Our findings suggest that continuous low-dose regimen of CTX increases the efficacy of targeting the tumor microvasculature, which produces therapeutic activity with decreased toxicity. The effects of the low-dose schedule of CTX may be further enhanced by concurrent administration of angiogenic inhibitor ginsenoside Rg3. As an antiangiogenic method, this regimen has the advantage of a reduced susceptibility to drug resistance mechanisms and improved animal survival.

Topics: Animals; Antineoplastic Agents, Phytogenic; Antineoplastic Combined Chemotherapy Protocols; Carcinoma, Lewis Lung; Cyclophosphamide; Ginsenosides; Mice; Mice, Inbred C57BL; Neovascularization, Pathologic; Survival Rate

To evaluate the anti-angiogenetic effect of the combination of low-dose cyclophosphamide(CTX) and ginsenoside Rg3 in mice with Lewis lung carcinoma, and to observe the anti-tumor effect, toxicity, adverse reaction of the treatment and survival time of the tumor bearing mice.. Holland C57/ BL6 Lewis lung carcinoma mice were taken as the model and randomly divided into 5 groups, i.e. the low-dose CTX (LDCTX) group, the maximum tolerable dose CTX (MTDCTX) group, the ginsenoside Rg3 (Rg3) group, the low-dose CTX combined with ginsenoside Rg3 group (LDCTX + Rg3), and the model group. Tumor volume, weight of mice, peripheral white blood cell counts and survival time of mice were observed, tumor microvascular density (MVD) and vascular endothelial growth factor (VEGF) gene expression were determined during the therapeutic course.. In the LDCTX group, tumor grew comparatively slow, no significant decrease in body weight or peripheral white blood cells, and survival time was prolonged. In the LDCTX + Rg3 group, the tumor inhibitory effect was more persistent and steady without any increase of toxicity or adverse reaction. Besides, the survival time of mice was prolonged (P < 0.01). MVD was lower in the LDCTX group than that in the MTDCTX group (P< 0. 05). Compared with the model group, MVD and VEGF expression were lower in the LDCTX and the Rg3 group, and the lowering action was more significant when the two drugs were used in combination (P < 0.05).. The combination of low-dose CTX and Rg3 has obvious synergetic action of anti-angiogenesis, it shows significant and persistent tumor inhibitory effect, with less toxic and adverse reaction, and could induce longer survival time than treatment of CTX or Rg3 alone.

Topics: Angiogenesis Inhibitors; Animals; Antineoplastic Agents, Phytogenic; Carcinoma, Lewis Lung; Cyclophosphamide; Drug Therapy, Combination; Female; Ginsenosides; Mice; Mice, Inbred C57BL; Neovascularization, Pathologic; Random Allocation