In vitro photoradiation therapy of the rat 9L gliosarcoma

1986 ◽  
Vol 64 (5) ◽  
pp. 775-779 ◽  
Author(s):  
Douglas Hamilton ◽  
John D. S. McKean ◽  
John Tulip ◽  
Donald Boisvert ◽  
Judy Cummins

✓ The authors have investigated various factors involved in the photoradiation treatment of 9L glioma cells. The cells were grown in tissue culture and exposed to light from a laser source that allowed accurate quantitation of the light energy. Cell death was determined following treatment using the trypan blue exclusion test. It was shown that the treatment is very wavelength-dependent following the absorption spectrum of hematoporphyrin derivative (HPD). The absorption peaks in the lower part of the spectrum are more efficient than those of higher wavelengths. Photoradiation therapy is more effective the higher the concentration of HPD. Intensity of light is a very important factor in calculating the total dose of light necessary for this treatment.

1983 ◽  
Vol 59 (3) ◽  
pp. 424-430 ◽  
Author(s):  
Junkoh Yamashita ◽  
Hajime Handa ◽  
Yasuhiko Tokuriki ◽  
Young Soo Ha ◽  
Shin-Ichi Otsuka ◽  
...  

✓ The authors examined the growth rate of mouse 203 glioma cells in vitro and found it to be markedly inhibited after exposure to ACNU for 5 minutes at a drug concentration of 100 µg/ml. Rats that had undergone intracranial implantation of T1 neurogenic tumor were treated by 5 mg/kg of ACNU administered either intravenously or intra-arterially. The median survival times for the control animals and the animals undergoing intravenous or intracarotid administration of ACNU were 23, 29, and 46 days, respectively. The difference in survival time between the intravenous and intracarotid administration groups was statistically significant (p < 0.01) when examined by the Cox-Mantel test. In a clinical trial, 17 patients with glioblastoma were treated by ACNU, eight intravenously and nine by the intra-arterial route. The drug was given in doses of 2 to 3 mg/kg at least twice before and twice after a course of postoperative radiotherapy. Intra-arterial administration was performed over a period of 5 minutes under local anesthesia. The median postoperative survival time for the patients in the intra-arterial group was 12.5 months, compared with 9.0 months for those in the intravenous group. The survival rate for the intra-arterial group was slightly higher, although statistically not significant, probably because the number of cases was small. The degree of thrombocytopenia due to ACNU tended to be less marked in the intra-arterially treated patients. The theoretical advantages of the intra-arterial administration of ACNU are discussed.


1991 ◽  
Vol 74 (6) ◽  
pp. 956-961 ◽  
Author(s):  
Rafael J. Tamargo ◽  
Allen K. Sills ◽  
Carla S. Reinhard ◽  
Michael L. Pinn ◽  
Donlin M. Long ◽  
...  

✓ Controlled-release polymers have facilitated the interstitial delivery of drugs within the central nervous system. In the present study, dexamethasone was incorporated into ethylene-vinyl acetate polymers, which were then implanted adjacent to a 9L gliosarcoma in the brain of Fischer 344 rats. The effect of interstitial delivery of dexamethasone on peritumoral edema was assessed and compared to the effect of dexamethasone delivered systemically. Eighty-five rats underwent intracranial implantation of the 9L gliosarcoma. Five days later, the animals were randomly assigned to one of four treatment groups: Group 1 received intracranial implantation of controlled-release polymers containing dexamethasone; Group 2 received intraperitoneal implantation of controlled-release polymers containing dexamethasone; Group 3 received serial intraperitoneal injections of dexamethasone; and Group 4 received sham treatment. The animals were sacrificed 3 days after initiation of therapy and their brains were removed for measurement of the water content (edema) in the tumor-bearing and contralateral hemispheres. Brain and plasma samples were analyzed by reverse-phase high-performance liquid chromatography to determine the tissue and plasma concentrations of dexamethasone. Measurement of the release kinetics of dexamethasone from the ethylene-vinyl acetate polymers in an in vitro system showed that the drug was released in a controlled, tapering fashion. During the first 3 days of controlled release in vitro, 330 µg of a total content of 7.5 mg of dexamethasone was released into the medium. Analysis of tissue for drug levels demonstrated, however, that the interstitial delivery of this fractional amount of dexamethasone within the brain resulted in levels 19 times higher than those achieved by administering the full dose of 7.5 mg systemically over a 3-day period. Conversely, the systemic administration of dexamethasone resulted in plasma levels 16 times higher than those measured in the interstitial delivery of dexamethasone in the brain. Brain-water content determinations showed that the interstitial controlled release of the fractional amount of dexamethasone within the brain was as effective in controlling peritumoral edema as systemic administration of the full dose by serial intraperitoneal injections. The study demonstrates the following: 1) controlled-release polymeric carriers deliver biologically active dexamethasone in a sustained fashion; 2) very high concentrations of dexamethasone in brain tissue can be achieved using interstitial polymer-mediated drug delivery while minimizing plasma concentrations of this drug which are sometimes associated with serious systemic side effects; and 3) peritumoral brain edema can be effectively treated by the interstitial delivery of dexamethasone directly within the tumor bed.


1990 ◽  
Vol 73 (3) ◽  
pp. 436-440 ◽  
Author(s):  
Jun-ichi Kuratsu ◽  
Yukitaka Ushio

✓ Platelet-derived growth factor (PDGF) is produced by glioma cells. However, there is heterogeneity among glioma cell lines in the production of PDGF. It has been demonstrated that U251MG cells produce a PDGF-like molecule while U105MG cells do not. Trapidil, a specific antagonist of PDGF, competes for receptor binding with PDGF. Therefore, the inhibitory effect of trapidil on the proliferation of glioma cells was investigated in vitro using two glioma cell lines. At 100 µg/ml, trapidil significantly inhibited the proliferation of U251MG cells (which produce the PDGF-like molecule). At the same trapidil concentration, the proliferation of U105MG cells (which do not produce the PDGF-like molecule) was not inhibited. The inhibitory effect of trapidil was remarkable on Days 3 and 4 of culture. After 4 days of incubation, the proliferation of U251MG cells was 46% of the control preparation. Trapidil enhanced the antitumor effect of 3-((4-amino-2-methyl-5-pyrimidinyl)ethyl)-1-(2-chloroethyl)-1-nitro-sourea (ACNU) against U251MG cells. The enhancing effect was highest on Days 4 and 6 of culture. After 6 days of incubation in the presence of 100 µg/ml trapidil and 1 µg/ml ACNU, the proliferation of U251MG cells was 18% of the control preparation. These findings suggest that trapidil interrupts the autocrine loop at the PDGF and PDGF-receptor level and that combination therapy with trapidil and ACNU may be useful in the treatment of glioma.


2002 ◽  
Vol 97 (1) ◽  
pp. 112-118 ◽  
Author(s):  
Myung-Jin Park ◽  
In-Chul Park ◽  
Jin-Heang Hur ◽  
Mi-Suk Kim ◽  
Hyung-Chan Lee ◽  
...  

Object. Expression of matrix metalloproteinases (MMPs) has been postulated to play a central role in brain tumor invasion; however, its underlying mechanism is not yet fully understood. In the present study, by assessing the effect of a specific p38 mitogen-activated protein kinase (MAPK) inhibitor, SB203580, on the secretion of MMPs and in vitro invasion of various glioma cells, the authors attempt to define the role of the p38 MAPK pathway in the regulation of MMPs and tissue inhibitors of metalloproteinases (TIMPs) activated by phorbol ester (phorbol-12-myristate-13-acetate [PMA]) in the D54 human glioblastoma cell line. Methods. The activation of MAPKs was determined using Western blot analysis after addition of phospho-specific antibodies against these kinases, the status of MMPs and TIMPs was analyzed using gelatin zymography and Western blot analysis, and the invasion rate of D54 cells and other glioma cells was analyzed using a modified Boyden chamber assay. Treatment of D54 cells with PMA activated two distinct MAPKs, extracellular signal-regulated kinase (ERK) 1/2 and p38 MAPK, but not c-Jun N-terminal kinase/stress-activated protein kinase. Induction of MMP-9 production and MMP-2 activation by PMA were blocked by SB203580, a specific inhibitor of p38 MAPK, but not by PD98059, a specific inhibitor of ERK 1/2. In addition, PMA-induced downregulation of TIMP-1 and TIMP-2 secretion and upregulation of the membrane type 1 MMP, a major activator of MMP-2 on the cell surface, were reversed by SB203580 in these cells; the PMA-induced increase of invasion in vitro decreased when SB203580 was added to the top compartment of a modified Boyden chamber; and the inhibitor also reduced the MMP secretion and PMA-induced in vitro invasion in various glioma cell lines. Conclusions. These results indicate that activation of p38 MAPK by PMA plays a central role in the regulation of MMPs and TIMPs in D54 cells, which has a major influence in tumor invasion and metastasis. Furthermore, inhibition of p38 MAPK by SB203580 blocked the secretion of MMPs and in vitro invasion of various glioma cells, underscoring a possible role of p38 MAPK inhibitors as antiinvasive and/or antimetastatic agents of malignant gliomas.


2000 ◽  
Vol 92 (1) ◽  
pp. 132-139 ◽  
Author(s):  
Peiyu Pu ◽  
Xuwen Liu ◽  
Aixue Liu ◽  
Jianling Cui ◽  
Yunting Zhang

Object. The goal of this study was to evaluate the effect of antisense epidermal growth factor receptor (EGFR) RNA on the growth of rat glioma cells in vitro and in vivo and to determine the feasibility of targeting the EGFR gene for gene therapy in gliomas.Methods. Antisense EGFR complementary (c)DNA was transfected into C6 glioma cells by using lipofectamine. In vitro studies, Southern and Northern blot analyses, in situ hybridization, and immunohistochemical staining were designed to examine the integration and expression of antisense EGFR constructs. The 3′(4,5-dimethylthiazol-2-yl)2,5-diphenyl tetrazolium bromide (MTT) assay and the average number of argyrophilic nuclear organizer regions (Ag-NORs) were used to evaluate cell proliferation, whereas the terminal deoxynucleotidyl transferase—mediated deoxyuridine triphosphate nick-end labeling (TUNEL) method and microscopy were used to observe cell apoptosis. As part of the in vivo studies, parental C6 cells and C6 cells transfected with EGFR antisense cDNA were implanted stereotactically into the right caudate nucleus of Wistar rats (C6-injected animals and transfected C6-injected animals). Rats with well-established cerebral C6 glioma foci were treated intratumorally with either antisense EGFR cDNA or empty-vector DNA by using lipofectamine (treated-C6 and control treated group). The general behavior and survival of the rats, findings on magnetic resonance images of their brains, histopathological changes, proliferation activity, and apoptosis of the cerebral gliomas in each group of rats were examined.Exogenous antisense EGFR cDNA was integrated into the genome of C6 cells and expressed. In clones with a high expression of the antisense construct, there was a dramatic decrease in endogenous EGFR messenger RNA and protein levels, reduced proliferation activity, and induction of apoptosis in vitro. The mean survival time of rats injected with C6 cells was 17.3 days. The mean survival time of rats injected with C6 cells followed by treatment with empty vector in lipofectamine was 15.4 days. Survival time was significantly prolonged in 100% of the rats injected with antisense-transfected C6 cells and in two thirds of the rats injected with C6 cells followed by antisense EGFR cDNA. Magnetic resonance imaging revealed distinct cerebral tumor foci in C6-injected rats and in control rats of the treated group, but none were found in the rats injected with transfected C6 cells. Furthermore, tumor foci disappeared completely in C6-injected rats treated with antisense EGFR cDNA. The cerebral gliomas of the rats treated by injection of antisense EGFR RNA were characterized by reduced proliferation activity and the induction of apoptosis.Conclusions. The results of this study indicate that EGFR plays an important role in the genesis of malignant gliomas. It may, therefore, be an effective target of antisense gene therapy in patients with gliomas.


1971 ◽  
Vol 34 (3) ◽  
pp. 324-334 ◽  
Author(s):  
John Mealey ◽  
Tsu T. Chen ◽  
George P. Schanz

✓ Eight biopsied glioblastomas were propagated in vitro through multiple, serial cell cultures which were exposed to dexamethasone and methylprednisolone in concentrations ranging from 0.25 to 400 µg/ml. The higher concentrations of both steroids produced inhibition of culture growth and cytotoxic damage which appeared relatively nonspecific. Although the responses observed were dose-dependent, the sensitivity among glioma cultures of different origins varied. Of the two steroids, Methylprednisolone was more injurious to glioma cells in vitro and was cytolytic in doses of 400 µg/ml. Growth inhibition was demonstrated after a 1-day exposure to this corticoid, but this effect was usually transient at lower doses. Thereafter, surviving resistant cells resumed their natural rate of growth in the continued presence of the steroid as well as under standard conditions of culture. Potential clinical applications of the antineoplastic properties of corticosteroids against the gliomas are discussed, emphasizing the need to investigate additional, possibly more efficacious compounds.


2002 ◽  
Vol 97 (3) ◽  
pp. 619-626 ◽  
Author(s):  
Tomohiro Kito ◽  
Etsushi Kuroda ◽  
Akira Yokota ◽  
Uki Yamashita

Object. In previous studies interferon-β (IFNβ) has been shown to suppress tumor growth. In this report, the antitumor effect of macrophages stimulated with IFNβ is investigated in murine gliomas in vitro. Methods. The authors examined the cytotoxic activity of IFNβ-stimulated peritoneal macrophages in glioma cells labeled with [3H]thymidine. The addition of IFNβ enhanced cytotoxic activity in gliomas as well as the nitric oxide (NO) production of macrophages in cocultures. Addition of NG-monomethyl-l-arginine (l-NMMA) and l-N6-(1-iminoethyl)-lysine, but not d-NMMA (an inactive analog of l-NMMA), blocked this cytotoxic activity. The addition of IFNβ had no direct effect on the growth of glioma cells. Because NO was not produced from macrophages treated with IFNβ alone and IFNβ-induced cytotoxic activity did not need cell-to-cell contact, the authors suspected that gliomas produce some soluble factors that act as cofactors for IFNβ-induced cytotoxic activity. Macrophages stimulated with IFNβ in the presence of glioma culture supernatants showed higher cytotoxicity against glioma cells than macrophages stimulated with IFNβ alone. Furthermore, NO was markedly produced by IFNβ-stimulated macrophages in the presence of glial culture supernatants. Conclusions. These data indicate that the antiglioma activity of IFNβ through macrophages is due to NO produced by macrophages and that glioma-derived soluble factors play a role as an essential cofactor in this activity.


1990 ◽  
Vol 73 (4) ◽  
pp. 594-600 ◽  
Author(s):  
William T. Couldwell ◽  
Jack P. Antel ◽  
Michael L. J. Apuzzo ◽  
Voon Wee Yong

✓ The protein kinase-C (PKC) second messenger system contributes to regulation of cell growth and differentiation. This study was undertaken to examine the effects of modulators of the PKC enzyme system on the state of differentiation and proliferation rates of human gliomas in vitro. The administration of the PKC-activating phorbol esters 4-beta-phorbol-12,13-dibutyrate (PDB) and phorbol-12-myristate-13-acetate (PMA) resulted in a dose-related inhibition of growth of human glioma cell lines in vitro as measured by 3H-thymidine uptake. The synthetic nonphorbol PKC activator (SC-9) produced an even more pronounced decrease of 3H-thymidine uptake. Diacylglycerol, an endogenous activator of the system, applied externally, transiently decreased the proliferation, in concordance with its short-lived existence in vivo. Conversely, the administration of 4-alpha-phorbol-12,13-didecanoate (α-PDD), a phorbol ester that binds but does not activate the enzyme, had no effect on the proliferation rate. At the dosages that maximally decreased proliferation, there was no evidence of direct glioma cell lysis induced by these agents as measured by a chromium-release assay. Immunocytochemical analysis and cytofluorometric measurement of glial fibrillary acidic protein (GFAP) staining in the treated cultures revealed an increase in GFAP staining over control cultures. In contrast to the response of glioma cells, nonmalignant human adult astrocytes treated with the PKC activators responded by increasing their proliferation rate. The authors postulate that the diametrically opposed effects of PKC activators on nonmalignant astrocytes versus glioma growth may be due to a high intrinsic PKC activity in glioma cells, with resultant down-regulation of enzyme activity following the administration of the pharmacological activators.


2005 ◽  
Vol 19 (3) ◽  
pp. 183-187 ◽  
Author(s):  
Daniel Araki Ribeiro ◽  
Mariza Akemi Matsumoto ◽  
Marco Antonio Húngaro Duarte ◽  
Mariangela Esther Alencar Marques ◽  
Daisy Maria Favero Salvadori

Recently, regular and white mineral trioxide aggregate (MTA) are being used in Dentistry as retrofilling materials. Genotoxicity and cytotoxicity tests form an important part of cancer research and risk assessment of potential carcinogens. Thus, the goal of this study was to examine the genotoxicity and cytotoxicity of regular and white MTA in vitro by the single cell gel (comet) assay and trypan blue exclusion test, respectively. Mouse lymphoma cells were exposed to two presentation forms of MTA at final concentrations ranging from 1 to 1,000 µg/mL for 3 h at 37°C. The results showed that both compounds tested did not produce genotoxic effects at all concentrations evaluated. Likewise, no statistically significant differences (p > 0.05) were observed in cytotoxicity. Taken together, our results suggest that regular and white MTA are not genotoxins and are not able to interfere in cellular viability as assessed by single cell gel (comet) assay and trypan blue assay, respectively.


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