Thymidine kinase-mediated killing of rat brain tumors

1993 ◽  
Vol 79 (5) ◽  
pp. 729-735 ◽  
Author(s):  
David Barba ◽  
Joseph Hardin ◽  
Jasodhara Ray ◽  
Fred H. Gage

✓ Gene therapy has many potential applications in central nervous system (CNS) disorders, including the selective killing of tumor cells in the brain. A rat brain tumor model was used to test the herpes simplex virus (HSV)-thymidine kinase (TK) gene for its ability to selectively kill C6 and 9L tumor cells in the brain following systemic administration of the nucleoside analog ganciclovir. The HSV-TK gene was introduced in vitro into tumor cells (C6-TK and 9L-TK), then these modified tumor cells were evaluated for their sensitivity to cell killing by ganciclovir. In a dose-response assay, both C6-TK and 9L-TK cells were 100 times more sensitive to killing by ganciclovir (median lethal dose: C6-TK, 0.1 µg ganciclovir/ml; C6, 5.0 µg ganciclovir/ml) than unmodified wild-type tumor cells or cultured fibroblasts. In vivo studies confirmed the ability of intraperitoneal ganciclovir administration to kill established brain tumors in rats as quantified by both stereological assessment of brain tumor volumes and studies of animal survival over 90 days. Rats with brain tumors established by intracerebral injection of wild-type or HSV-TK modified tumor cells or by a combination of wild-type and HSV-TK-modified cells were studied with and without ganciclovir treatments. Stereological methods determined that ganciclovir treatment eliminated tumors composed of HSV-TK-modified cells while control tumors grew as expected (p < 0.001). In survival studies, all 10 rats with 9L-TK tumors treated with ganciclovir survived 90 days while all untreated rats died within 25 days. Curiously, tumors composed of combinations of 9L and 9L-TK cells could be eliminated by ganciclovir treatments even when only one-half of the tumor cells carried the HSV-TK gene. While not completely understood, this additional tumor cell killing appears to be both tumor selective and local in nature. It is concluded that HSV-TK gene therapy with ganciclovir treatment does selectively kill tumor cells in the brain and has many potential applications in CNS disorders, including the treatment of cancer.

1971 ◽  
Vol 35 (3) ◽  
pp. 303-308 ◽  
Author(s):  
Tatsuya Kobayashi ◽  
Louis Bakay ◽  
Joseph C. Lee

✓ The deposition of Hg203-chlormerodrin was studied in intracranial tumors in mice induced by implantation of 20-methyl cholanthrene by tissue assay, as well as light microscopic and electron microscopic autoradiography. The investigations were carried out in astrocytomas, glioblastomas, and meningeal tumors. The chlormerodrin content of the tumors exceeded that of normal brain with a significant tumor/brain ratio ranging from 5.8 to 22.5. It was found that the chlormerodrin molecule becomes rapidly incorporated in the tumor cells, with a preference for that portion of the cytoplasm associated with the vacuolar system.


2001 ◽  
Vol 95 (6) ◽  
pp. 1012-1019 ◽  
Author(s):  
Martin A. Proescholdt ◽  
Marsha J. Merrill ◽  
Barbara Ikejiri ◽  
Stuart Walbridge ◽  
Aytac Akbasak ◽  
...  

Object. Immunotherapy for glioblastoma has been uniformly ineffective. The immunological environment of the brain, with its low expression of major histocompatibility complex (MHC) molecules and limited access for inflammatory cells and humoral immune effectors due to the blood—brain barrier (BBB), may contribute to the failure of immunotherapy. The authors hypothesize that brain tumors are protected from immune surveillance by an intact BBB at early stages of development. To investigate the immunological characteristics of early tumor growth, the authors compared the host response to a glioma implanted into the brain and into subcutaneous tissue. Methods. Samples of tumors growing in the brain or subcutaneously in rats were obtained for 7 consecutive days and were examined immunohistochemically for MHC Class I & II molecules, and for CD4 and CD8 lymphocyte markers. Additionally, B7-1 costimulatory molecule expression and lymphocyte-specific apoptosis were examined. Conclusions. On Days 3 and 4 after implantation, brain tumors displayed significantly lower MHC Class II expression and lymphocytic infiltration (p < 0.05). After Day 5, however, no differences were detected. The MHC Class II expressing cells within the brain tumors appeared to be infiltrating microglia. Minimal B7-1 expression combined with lymphocyte-specific apoptosis were detected in both brain and subcutaneous tumors. Low MHC Class II expression and low lymphocytic infiltration at early time points indicate the importance of the immunologically privileged status of the brain during early tumor growth. These characteristics disappeared at later time points, possibly because the increasing perturbation of the BBB alters the specific immunological environment of the brain. The lack of B7-1 expression combined with lymphocyte apoptosis indicates clonal anergy of glioma-infiltrating lymphocytes regardless of implantation site.


2000 ◽  
Vol 92 (2) ◽  
pp. 249-254 ◽  
Author(s):  
Roger J. Packer ◽  
Cory Raffel ◽  
Judith G. Villablanca ◽  
Jörg-Christian Tonn ◽  
Stefan E. Burdach ◽  
...  

Object. The outcome for children with recurrent malignant brain tumors is poor. The majority of patients die of progressive disease within months of relapse, and other therapeutic options are needed. The goal of this Phase I study was to evaluate the safety of in vivo suicide gene therapy in 12 children with recurrent, malignant, supratentorial brain tumors.Methods. After optimal repeated tumor resection, multiple injections of murine vector—producing cells shedding murine replication—defective retroviral vectors coding the herpes simplex virus thymidine kinase type 1 (HSV-Tk1) gene were made into the rim of the resection cavity. Fourteen days after the vector-producing cells were injected, ganciclovir was administered for 14 days. The retroviral vector that was used only integrated and expressed HSV-Tk1 in proliferating cells, which are killed after a series of metabolic events lead to cell death. The median age of the patients was 11 years (range 2–15 years). Treated brain tumors included seven malignant gliomas, two ependymomas, and three primitive neuroectodermal tumors. The patients were treated with one of three escalating dose concentrations of vector-producer cells. Four transient central nervous system adverse effects were considered possibly related to the vector-producing cells. In no child did permanent neurological worsening or ventricular irritation develop, and tests for replication-competent retroviruses yielded negative findings.Conclusions. This Phase I study demonstrates that in vivo gene therapy in which a replication-defective retroviral vector in murine vector—producing cells is delivered by brain injections can be performed with satisfactory safety in a select group of children with localized supratentorial brain tumors.


1992 ◽  
Vol 76 (3) ◽  
pp. 513-519 ◽  
Author(s):  
Stephen C. Saris ◽  
Paul Spiess ◽  
Daniel M. Lieberman ◽  
Shan Lin ◽  
Stuart Walbridge ◽  
...  

✓ Methods have recently been described for the isolation and expansion of lymphocytes that have trafficked into animal and human tumors. These CD8-positive tumor-infiltrating lymphocytes (TIL's) have exceptional trafficking ability to, and efficacy against, tumor targets in extracranial sites. Prior to Phase I clinical trials for patients with gliomas, adoptive immunotherapy with TIL's was studied in a mouse model of primary brain tumors to determine if intracerebral tumors have a similar response. Glioma 261 (GL261) tumors were grown in the subcutaneous space of C57BL/6 mice. After enzymatic digestion, the cells were incubated in vitro with interleukin-2 (IL-2) until a confluent population of T lymphocytes was present. The in vitro efficacy of these TIL's was tested against fresh GL261 targets with a chromium release assay; the in vivo efficacy was tested against GL261 tumors in the liver and against irradiated and nonirradiated GL261 tumors in the brain. Mice received one of the following: intraperitoneal saline; intraperitoneal IL-2 (7500 to 50,000 U three times daily for 5 days); IL-2 plus intravenous TIL's (1 to 3 × 107 cells); 10 Gy cranial irradiation; irradiation plus IL-2; or irradiation plus IL-2 plus TIL's. The TIL preparation killed 77% of tumor targets in 4 hours at an effector:target ratio of 100:1. In animals with GL261 tumors in the liver, at 2 weeks there were 93 ± 37, 128 ± 45, and 21 ± 14 liver metastases in the control, IL-2, and IL-2 plus TIL groups, respectively. However, in animals with GL261 tumors in the brain, no treatment group had an increased survival rate compared to the control group. It is concluded that, although TIL and IL-2 immunotherapy can be used effectively to treat brain tumors in vitro and at sites outside the central nervous system, it is ineffective against the same type of tumor in the brain. Different methods of delivery or different combinations of these immunomodulators may be more effective; however, based on these findings, treatment of patients with IL-2 and TIL cannot be recommended until efficacy has been demonstrated in an animal model.


1973 ◽  
Vol 39 (5) ◽  
pp. 636-641 ◽  
Author(s):  
Ivanka Lolova ◽  
Margarita Kamenova

✓ The authors report the histological and histochemical examination of four cases of hemangiopericytoma. The tumors showed mature, differentiated, and undifferentiated cells with frequent mitoses, and an abundance of anaplastic cells. The histochemical characteristics of the tumor cells are summarized and compared to those of pericytes under normal or pathological conditions.


1974 ◽  
Vol 40 (6) ◽  
pp. 706-716 ◽  
Author(s):  
Yukitaka Ushio ◽  
Toru Hayakawa ◽  
Heitaro Mogami

✓ Malignant gliomas were induced in strain ddN mice by intracerebral implantation of a 20-methylcholanthrene pellet. The uptake and distribution of tritiated methotrexate (MTX-3H) in the tumor were investigated by radioactive assay and radioautography after single intravenous or intrathecal injections. By either route, a large amount of MTX-3H was taken up by gliomas, and a significantly higher concentration was observed in tumor than in the brain tissue. At 24 hours after intrathecal administration, the uptake of MTX-3H by gliomas exceeded that achieved after intravenous injection, although the drug dosage in the latter was 10 times that in the former.


2000 ◽  
Vol 92 (6) ◽  
pp. 1002-1008 ◽  
Author(s):  
Katsuyuki Asaoka ◽  
Mitsuhiro Tada ◽  
Yutaka Sawamura ◽  
Jun Ikeda ◽  
Hiroshi Abe

Object. Recombinant adenovirus is used as a competent vector in a wide spectrum of cancer gene therapies because of its high efficiency in gene delivery. To study the feasibility of gene therapy in malignant gliomas, the authors examined the antiproliferative effect of the adenovirally transduced wild-type p53 tumor suppressor gene by using 15 different high-grade glioma cell lines.Methods. Although growth suppression in association with a high adenoviral p53 transduction efficiency was seen in five of 15 cell lines, it was not observed in the remaining 10 cell lines. To clarify the underlying mechanism, we examined the expression levels of the Coxsackievirus and adenovirus receptor (CAR), which is the primary receptor for adenovirus, and of the integrins αvβ3 and αvβ5, which promote adenoviral internalization. The expression level of the CAR gene showed a close correlation to adenoviral gene transduction efficiency in the tested cell lines, whereas the expression levels of the integrins did not. The CAR expression was decreased by wild-type p53 transduction in U251MG cells harboring mutant p53 and increased by antisense inhibition of p53 in LN443 cells with endogenous wild-type p53.Conclusions. The results of this study indicate that CAR expression is a critical determinant of transduction efficiencies in adenovirus-based gene therapy for human malignant gliomas.


1978 ◽  
Vol 49 (2) ◽  
pp. 303-307 ◽  
Author(s):  
Nobuyuki Kawano ◽  
Yoshio Miyasaka ◽  
Kenzoh Yada ◽  
Hideo Atari ◽  
Kenichi Sasaki

✓ A case of diffuse cerebrospinal gliomatosis is presented, with widespread involvement of the brain, cranial nerves, and spinal cord. This case showed a far more extensive distribution of tumor cells than previously reported cases of gliomatosis cerebri. The clinical picture and oncogenesis of gliomatosis cerebri is briefly discussed.


1983 ◽  
Vol 58 (5) ◽  
pp. 650-653 ◽  
Author(s):  
Nicholas J. Patronas ◽  
Javad Hekmatpanah ◽  
Kunio Doi

✓ Perfluorocarbon, a new tumor-seeking x-ray contrast agent, was injected into three rats with experimental brain tumors. After 1 to 3 days the rats were sacrificed, and the brains were removed and subjected to x-ray study. All showed dense radiopaque areas which correlated with the size and shape of the corresponding brain tumors. Conversely, none of the radiograms taken of the brain tumor in five rats receiving no perfluorocarbon (control animals) showed similar increased density. These findings suggest that perfluorocarbon may serve a useful role as a contrast medium for computerized tomography studies of brain tumors in man.


1987 ◽  
Vol 67 (2) ◽  
pp. 258-262 ◽  
Author(s):  
Raymond Sawaya ◽  
Mario Zuccarello ◽  
Robert Highsmith

✓ This study was undertaken to confirm the presence of alpha-1-antitrypsin (α1-AT) in human brain tumors and to attempt to elucidate its significance. Seventy-seven consecutive unselected patients with various brain tumors were entered in this study. The α1-AT and α2-macroglobulin contents of the tumor extracts were qualitatively assessed by Ouchterlony immunodiffusion techniques. Plasminogen activator (PA) activity was assayed electrophoretically on sodium dodecyl sulfate gels. The patients were divided into two groups according to the positivity of their tumors to α1-AT. Sixty-eight percent of the tumors were positive for α1-AT, and all specimens were negative for α2-macroglobulin. Clinical and biological parameters obtained in all study patients failed to show statistically significant differences between the two groups with the exception of PA activity (p = 0.001), the peritumoral edema as seen on computerized tomography, and the preoperative serum fibrinogen level. These three parameters were higher in the group with specimens positive to α1-AT. This study supports the hypothesis that α1-AT is produced primarily by tumor cells in proportion to the regional proteolytic and inflammatory activity, and may protect the tumor cells.


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