This study was to investigate the cytotoxic effects on pituitary adenoma cell lines GH3/MMQ/AtT20 induced by RGD-FasL and the underlying mechanism. Fas/DcR3 mRNAs were detected by RT-PCR and their surface expressions ...This study was to investigate the cytotoxic effects on pituitary adenoma cell lines GH3/MMQ/AtT20 induced by RGD-FasL and the underlying mechanism. Fas/DcR3 mRNAs were detected by RT-PCR and their surface expressions were measured by flow cytometry. Cytotoxicity exerted by RGD-FasL on tumor cells was measured with MTT assay and the induced apoptosis was determined by agarose gel electrophoresis. The cell cycle and apoptosis was assessed by flow cytometry with PI staining. The expressions of caspase8/9/3, Bcl-2, RANKL and JNK2 were detected by Western blotting. Approximately 13.7% of GH3 cells, 25.5% of MMQ cells, 22.2% of AtT20 cells express Fas, while 23.9% of GH3 cells, 24.1% of MMQ cells, 4.6% of AtT20 cells express DcR3. The cytotoxic effects of FasL/RGD-FasL on tumor cells were all taken in a dose-dependent manner. Cell lines MMQ/AtT20 showed the same sensitivity to RGD-FasL as to FasL, while cell line GH3 was less sensitive to RGD-FasL. The cell cycle analysis indicated that RGD-FasL could inhibit cells in G0/G1 phase and G2/M phase. In MMQ and AtT20 cells treated with RGD-FasL, the AI was not significantly different from that treated with FasL, while in GH3 cells treated with RGD-FasL, the AI was lower than that treated with FasL. The expressions of caspase-8/9/3, RANKL and JNK2 were increased while that of Bcl-2 was decreased after treatment with RGD-FasL, suggesting that RGD-FasL induces apoptosis through caspase activation. We concluded that RGD-FasL could possibly be considered as a novel therapeutical candidate for the treatment of pituitary adenomas. Cellular ＆ Molecular Immunology.展开更多
Despite impressive results obtained in animal models, the clinical use of Fas ligand （FasL） as an anticancer drug is limited by severe toxicity. Systemic toxicity of death ligands may be prevented by using genes enc...Despite impressive results obtained in animal models, the clinical use of Fas ligand （FasL） as an anticancer drug is limited by severe toxicity. Systemic toxicity of death ligands may be prevented by using genes encoding membrane-bound death ligands and by targeted transgene expression through either targeted transduction or targeted transcription. Selective induction of tumor cell death is a promising anticancer strategy. A fusion protein is created by fusing the extracellular domain of Fas ligand （FasL） to the peptide arginine-glycine-aspartic acid （RGD） that selectively targets avβ-integrins on tumor endothelial cells. The purpose of this study is to evaluate the effects of RGD-FasL on tumor growth and survival in a murine hepatocellular carcinoma （HCC） tumor model. Treatment with RGD-FasL displaying an obvious suppressive effect on the HCC tumor model as compared to that with FasL （p 〈 0.05） and resulted in a more additive effect on tumor growth delay in this model. RGD-FasL treatment significantly enhanced mouse survival and caused no toxic effect, such as weight loss, organ failure, or other treatment-related toxicities. Apoptosis was detected by flow cytometric analysis and TUNEL assays; those results also showed that RGD-FasL is a more potent inducer of cell apoptosis for H22 and H9101 cell lines than FasL （p 〈 0.05）. In conclusion, RGD-FasL appears to be a low-toxicity selective inducer of tumor cell death, which merits further investigation in preclinical and clinical studies. Furthermore, this approach offers a versatile technology for complexing target ligands with therapeutic recombinant proteins. To distinguish the anti-tumor effects of FasL in vivo, tumor and liver tissues were harvested to examine for evidence of necrotic cells, tumor cells, or apoptotic cells by Hematoxylin and eosin （H＆E） staining.展开更多
文摘This study was to investigate the cytotoxic effects on pituitary adenoma cell lines GH3/MMQ/AtT20 induced by RGD-FasL and the underlying mechanism. Fas/DcR3 mRNAs were detected by RT-PCR and their surface expressions were measured by flow cytometry. Cytotoxicity exerted by RGD-FasL on tumor cells was measured with MTT assay and the induced apoptosis was determined by agarose gel electrophoresis. The cell cycle and apoptosis was assessed by flow cytometry with PI staining. The expressions of caspase8/9/3, Bcl-2, RANKL and JNK2 were detected by Western blotting. Approximately 13.7% of GH3 cells, 25.5% of MMQ cells, 22.2% of AtT20 cells express Fas, while 23.9% of GH3 cells, 24.1% of MMQ cells, 4.6% of AtT20 cells express DcR3. The cytotoxic effects of FasL/RGD-FasL on tumor cells were all taken in a dose-dependent manner. Cell lines MMQ/AtT20 showed the same sensitivity to RGD-FasL as to FasL, while cell line GH3 was less sensitive to RGD-FasL. The cell cycle analysis indicated that RGD-FasL could inhibit cells in G0/G1 phase and G2/M phase. In MMQ and AtT20 cells treated with RGD-FasL, the AI was not significantly different from that treated with FasL, while in GH3 cells treated with RGD-FasL, the AI was lower than that treated with FasL. The expressions of caspase-8/9/3, RANKL and JNK2 were increased while that of Bcl-2 was decreased after treatment with RGD-FasL, suggesting that RGD-FasL induces apoptosis through caspase activation. We concluded that RGD-FasL could possibly be considered as a novel therapeutical candidate for the treatment of pituitary adenomas. Cellular ＆ Molecular Immunology.
基金Acknowledgement This work was supported by a grant from the Natural Science Foundation of Fujian Province （No.C0710046）.
文摘Despite impressive results obtained in animal models, the clinical use of Fas ligand （FasL） as an anticancer drug is limited by severe toxicity. Systemic toxicity of death ligands may be prevented by using genes encoding membrane-bound death ligands and by targeted transgene expression through either targeted transduction or targeted transcription. Selective induction of tumor cell death is a promising anticancer strategy. A fusion protein is created by fusing the extracellular domain of Fas ligand （FasL） to the peptide arginine-glycine-aspartic acid （RGD） that selectively targets avβ-integrins on tumor endothelial cells. The purpose of this study is to evaluate the effects of RGD-FasL on tumor growth and survival in a murine hepatocellular carcinoma （HCC） tumor model. Treatment with RGD-FasL displaying an obvious suppressive effect on the HCC tumor model as compared to that with FasL （p 〈 0.05） and resulted in a more additive effect on tumor growth delay in this model. RGD-FasL treatment significantly enhanced mouse survival and caused no toxic effect, such as weight loss, organ failure, or other treatment-related toxicities. Apoptosis was detected by flow cytometric analysis and TUNEL assays; those results also showed that RGD-FasL is a more potent inducer of cell apoptosis for H22 and H9101 cell lines than FasL （p 〈 0.05）. In conclusion, RGD-FasL appears to be a low-toxicity selective inducer of tumor cell death, which merits further investigation in preclinical and clinical studies. Furthermore, this approach offers a versatile technology for complexing target ligands with therapeutic recombinant proteins. To distinguish the anti-tumor effects of FasL in vivo, tumor and liver tissues were harvested to examine for evidence of necrotic cells, tumor cells, or apoptotic cells by Hematoxylin and eosin （H＆E） staining.
