The effects of rat C6 glioma cells and in vivo tumor by atmospheric pressure cold plasma jet

SummaryTreatment of rat C6 glioma with high doses of 13 cis-retinoic acid (cRA) was responsible for death related to haemorrhagic necrosis localized to the tumor. Our aim was to explore this adverse effect of retinoid treatment. We show that cRA-treated C6 glioma at 25 mg/kg/day for 18 days exhibits in vivo an increased t-PA activity, which is responsible for a localized tumor fibrinolytic activity. Production of t-PA is supported by specific enhancement of gene expression, as was shown by the increase in t-PA mRNA (X 2.3). This production is a direct effect of cRA when treating the tumor, since tumor cells themself do not produce enough t-PA and treatment of control rats does not increase the t-PA level. t-PA production by rat C6 glioma is in vivo related to the specific synthesis of t-PA by the C6 cell-line. The stimulation of C6 cell-line by cRA in vitro is dose-dependent and reached a maximum for 3 and 30 |iM at the 72nd h. So cRA-treated C6 glioma cells produce t-PA which appears to be the major species associated with the fibrinolytic activity-induced intra-tumoral haemorrhage after exposure to retinoid treatment.

Download Full-text

Gene Therapy with HSV1-sr39TK/GCV Exhibits a Stronger Therapeutic Efficacy Than HSV1-TK/GCV in Rat C6 Glioma Cells

The Scientific World JOURNAL ◽

10.1155/2013/951343 ◽

2013 ◽

Vol 2013 ◽

pp. 1-10 ◽

Cited By ~ 3

Author(s):

Lei-qing Li ◽

Fang Shen ◽

Xiao-yan Xu ◽

Hong Zhang ◽

Xiao-feng Yang ◽

...

Keyword(s):

Gene Therapy ◽

Therapeutic Efficacy ◽

Gene Transfection ◽

Glioma Cells ◽

C6 Glioma ◽

C6 Glioma Cells ◽

Transfection Efficacy ◽

Rat C6 Glioma

Although the combination of herpes simplex virus type 1 (HSV-1) thymidine kinase (TK) with ganciclovir (GCV) has been shown as a promising suicide gene treatment strategy for glioma, the almost immunodepressive dose of GCV required for its adequatein vivoefficacy has hampered its further clinical application. Therefore, In order to reduce the GCV dose required, we aim to compare the therapeutic efficacy of HSV1-sr39TK, an HSV1-TK mutant with increased GCV prodrug catalytic activity, with wildtype TK in C6 glioma cells. Accordingly, rat C6 glioma cells were first transfected with pCDNA-TK and pCDNA-sr39TK, respectively, and the gene transfection efficacy was verified by immunocytochemistry and western blot analysis. Then thein vivosensitivity of these transfected C6-TK and C6-sr39TK cells to GCV was determined by 3-(4,5)-dimethylthiahiazo-(-z-y1)-3,5-di-phenytetrazoliumromide (MTT) colorimetric assay and Hoechst-propidium iodide (PI) staining. Finally, a subcutaneously C6 xenograft tumor model was established in the nude mice to test thein vitroefficacy of TK/GCV gene therapy. Our results showed that, as compared with wildtype TK, HSV1-sr39TK/GCV demonstrated a stronger therapeutic efficacy against C6 glioma bothin vitroandin vivo, which, by reducing the required GCV dose, might warrant its future use in the treatment of glioma under clinical setting.

Download Full-text

Radiosensitivity of glioma to Gamma Knife treatment enhanced in vitro and in vivo by RNA interfering Ku70 that is mediated by a recombinant adenovirus

Journal of Neurosurgery ◽

10.3171/2010.7.gks10972 ◽

2010 ◽

Vol 113 (Special_Supplement) ◽

pp. 228-235 ◽

Cited By ~ 4

Author(s):

Qiang Jia ◽

Yanhe Li ◽

Desheng Xu ◽

Zhenjiang Li ◽

Zhiyuan Zhang ◽

...

Keyword(s):

Western Blot ◽

Gamma Knife ◽

Blot Analysis ◽

Western Blot Analysis ◽

Glioma Cells ◽

C6 Glioma ◽

C6 Glioma Cells ◽

C6 Cells

Object The authors sought to evaluate modification of the radiation response of C6 glioma cells in vitro and in vivo by inhibiting the expression of Ku70. To do so they investigated the effect of gene transfer involving a recombinant replication-defective adenovirus containing Ku70 short hairpin RNA (Ad-Ku70shRNA) combined with Gamma Knife treatment (GKT). Methods First, Ad-Ku70shRNA was transfected into C6 glioma cells and the expression of Ku70 was measured using Western blot analysis. In vitro, phenotypical changes in C6 cells, including proliferation, cell cycle modification, invasion ability, and apoptosis were evaluated using the MTT (3′(4,5-dimethylthiazol-2-yl)2,5-diphenyltetrazolium bromide) assay, Western blot analysis, and cell flow cytometry. In vivo, parental C6 cells transfected with Ad-Ku70shRNA were implanted stereotactically into the right caudate nucleus in Sprague-Dawley rats. After GKS, apoptosis was analyzed using the TUNEL (terminal deoxynucleotidyl transferase–mediated deoxyuridine triphosphate nick-end labeling) method. The inhibitory effects on growth and invasion that were induced by expression of proliferating cell nuclear antigen and matrix metalloproteinase–9 were determined using immunohistochemical analyses. Results The expression of Ku70 was clearly inhibited in C6 cells after transfection with Ad-Ku70shRNA. In vitro following transfection, the C6 cells showed improved responses to GKT, including suppression of proliferation and invasion as well as an increased apoptosis index. In vivo following transfection of Ad-Ku70shRNA, the therapeutic efficacy of GKT in rats with C6 gliomas was greatly enhanced and survival times in these animals were prolonged. Conclusions Our data support the potential for downregulation of Ku70 expression in enhancing the radiosensitivity of gliomas. The findings of our study indicate that targeted gene therapy–mediated inactivation of Ku70 may represent a promising strategy in improving the radioresponsiveness of gliomas to GKT.

Download Full-text