CD95/CD95 ligand-independent potentiation of treosulfan cytotoxicity by BSO in malignant glioma cells in vitro and in vivo

Background/Aims: Cyclin D1 (CCND1) is frequently overexpressed in malignant gliomas. We have previously shown ectopic overexpression of CCND1 in human malignant gliomas cell lines. Methods: Quantitative reverse transcriptase PCR (qRT-PCR) and Western Blot (WB) was performed to investigate the expression of CCND1 in glioma tissues and cell lines. The biological function of CCND1 was also investigated through knockdown and overexpression of BCYRN1 in vitro. Results: Here we reported that CCND1 expression was positively associated with the pathological grade and proliferative activity of astrocytomas, as the lowest expression was found in normal brain tissue (N = 3) whereas the highest expression was in high-grade glioma tissue (N = 25). Additionally, we found that the expression level of CCND1 was associated with IC50 values in malignant glioma cell lines. Forced inhibition of CCND1 increased temozolomide efficacy in U251 and SHG-44 cells. After CCND1 overexpression, the temozolomide efficacy decreased in U251 and SHG-44 cells. Colony survival assay and apoptosis analysis confirmed that CCND1 inhibition renders cells more sensitive to temozolomide treatment and temozolomide-induced apoptosis in U251 and SHG-44 cells. Inhibition of P-gp (MDR1) by Tariquidar overcomes the effects of CCND1 overexpression on inhibiting temozolomide-induced apoptosis. Inhibition of CCND1 inhibited cell growth in vitro and in vivo significantly more effectively after temozolomide treatments than single temozolomide treatments. Finally, inhibition of CCND1 in glioma cells reduced tumor volume in a murine model. Conclusion: Taken together, these data indicate that CCND1 overexpression upregulate P-gp and induces chemoresistance in human malignant gliomas cells and that inhibition of CCND1 may be an effective means of overcoming CCND1 associated chemoresistance in human malignant glioma cells.

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Vimentin and glial fibrillary acidic protein are codistributed in the same intermediate filament system of malignant glioma cells in vivo

Virchows Archiv B Cell Pathology Including Molecular Pathology ◽

10.1007/bf02890003 ◽

1988 ◽

Vol 56 (1) ◽

pp. 67-70 ◽

Cited By ~ 11

Author(s):

Werner Paulus ◽

Wolfgang Roggendorf

Keyword(s):

Glial Fibrillary Acidic Protein ◽

Malignant Glioma ◽

Intermediate Filament ◽

Glioma Cells ◽

Acidic Protein ◽

Filament System ◽

Malignant Glioma Cells

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Targeting adenovirus to CD80 and CD86 receptors increases gene transfer efficiency to malignant glioma cells

Journal of Neurosurgery ◽

10.3171/jns-07/09/0617 ◽

2007 ◽

Vol 107 (3) ◽

pp. 617-627 ◽

Cited By ~ 28

Author(s):

Ilya V. Ulasov ◽

Angel A. Rivera ◽

Yu Han ◽

David T. Curiel ◽

Zeng B. Zhu ◽

...

Keyword(s):

Gene Therapy ◽

Brain Tumors ◽

Malignant Glioma ◽

Malignant Gliomas ◽

Glioma Cells ◽

Luciferase Reporter ◽

Transduction Efficiency ◽

Wild Type ◽

Malignant Glioma Cells

Object Gene therapy protocols for malignant gliomas utilize adenoviral vectors that rely almost exclusively on the adenovirus serotype 5 (Ad5) backbone. The authors have previously shown that chimeric vectors that bind to the Ad3 receptor, or CD46, increase the transduction efficiency of malignant brain tumors. In light of the debate regarding the efficacy of CD46 compared with CD80/CD86 in binding Ad3 virions, the authors now examine the expression and transduction efficiency of Ad5/3 chimeras that bind via CD80/CD86. Methods The authors first analyzed CD80/CD86 expression in glioma cell lines. They then used three replication-defective vectors containing a luciferase reporter gene: Ad5/3 (containing the tail and shaft domain of Ad5 and the knob domain of Ad3); Ad3/5 (containing the tail of Ad5, shaft of Ad3, and knob of Ad5); and Ad3/3 (containing the tail of Ad5, shaft of Ad3, and knob of Ad3). These vectors were analyzed both in vitro and in vivo against malignant glioma cells. To examine further the effect of Ad5/3 fiber modification, the authors created an oncolytic vector, conditionally replicative Ad5/3 (CRAd5/3). Results The Ad5/3 vector showed a 10- to 100-fold enhanced transduction efficiency of malignant glioma compared with replication-defective wild-type adenovirus (reAd5) (p < 0.05). Moreover the use of Ad5/3 reduced transgene expression by more than 90% in normal human brain cells compared with reAd5. Finally, the use of CRAd5/3 inhibited tumor cell proliferation by 43% more than replication-competent wild-type virus in vitro (p < 0.05). Conclusions The results of this study demonstrate that the Ad5/3 vector offers superior transduction efficiency and low toxicity in the setting of brain tumors, and therefore represents a potential new approach to gene therapy for malignant gliomas.

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