The organotypic multicellular spheroid is a relevant three-dimensional model to study adenovirus replication and penetration in human tumors in vitro.

The use of adenoviruses for gene transfer and as oncolytic agents is currently receiving widespread attention. As specific constraints to adenovirus distribution and spread cannot be studied in cell cultures, there is a need for an in vitro three-dimensional (3D) model mimicking the in vivo biology of tumors. We studied the interactions between tumor and adenoviruses using multicellular spheroids grown from primary brain tumor material. Using beta-galactosidase and luciferase reporter genes expressed by replication-defective adenoviruses, we showed that infection was restricted to the first layer of cells. Using a replication-competent adenovirus expressing the luciferase gene, we showed that transgene expression in the spheroid was considerably enhanced and that viral spreading deep into the 3D structure took place. In addition, a tetrazolium salt-based metabolic assay could be used to compare the oncolytic activity of different concentrations of replication-competent adenoviruses. We can conclude that organotypic spheroids offer a versatile in vitro system for studying distribution, spread, and oncolysis by adenoviruses in a clinically relevant model.

[1]  C. Avezaat,et al.  Treatment of malignant gliomas with a replicating adenoviral vector expressing herpes simplex virus-thymidine kinase. , 2001, Cancer research.

[2]  J. Grill,et al.  Combined targeting of adenoviruses to integrins and epidermal growth factor receptors increases gene transfer into primary glioma cells and spheroids. , 2001, Clinical cancer research : an official journal of the American Association for Cancer Research.

[3]  M. Israel,et al.  Pretreatment with protease is a useful experimental strategy for enhancing adenovirus-mediated cancer gene therapy. , 2000, Human gene therapy.

[4]  J. Bergelson,et al.  The dual impact of coxsackie and adenovirus receptor expression on human prostate cancer gene therapy. , 2000, Cancer research.

[5]  S. Kyo,et al.  Effect of extra cellular matrix in adenovirus-mediated gene transfer into endothelial cells. , 2000, Transplantation proceedings.

[6]  C. Balagué,et al.  Replicative adenoviruses for cancer therapy , 2000, Nature Biotechnology.

[7]  R. Kuwano,et al.  The coxsackievirus-adenovirus receptor protein as a cell adhesion molecule in the developing mouse brain. , 2000, Brain research. Molecular brain research.

[8]  L. Nielsen,et al.  The use of laser scanning cytometry to assess depth of penetration of adenovirus p53 gene therapy in human xenograft biopsies. , 1999, The American journal of pathology.

[9]  R. Bjerkvig,et al.  Extracellular matrix-induced cell migration from glioblastoma biopsy specimens in vitro , 1999, Acta Neuropathologica.

[10]  U. Fischer,et al.  Comparative amplification analysis of human glioma tissue and glioma derived fragment spheroids using reverse chromosome painting (RCP). , 1996, Anticancer research.

[11]  J. Murray,et al.  A mathematical model of glioma growth: the effect of extent of surgical resection , 1996, Cell proliferation.

[12]  S. Leenstra,et al.  Long‐term culture of organotypic multicellular glioma spheroids: a good culture model for studying gliomas , 1995, Neuropathology and applied neurobiology.

[13]  J. Tonn,et al.  Collagens, integrins and the mesenchymal drift in glioblastomas: A comparison of biopsy specimens, spheroid and early monolayer cultures , 1994, International journal of cancer.

[14]  P. Olive,et al.  Drug and radiation resistance in spheroids: cell contact and kinetics , 1994, Cancer and Metastasis Reviews.

[15]  J. Roth,et al.  Induction of chemosensitivity in human lung cancer cells in vivo by adenovirus-mediated transfer of the wild-type p53 gene. , 1994, Cancer research.

[16]  R. Bjerkvig,et al.  Multicellular tumor spheroids from human gliomas maintained in organ culture. , 1990, Journal of neurosurgery.

[17]  R. Sutherland.  Cell and environment interactions in tumor microregions: the multicell spheroid model. , 1988, Science.

[18]  A. Moscona.  THE DEVELOPMENT IN VITRO OF CHIMERIC AGGREGATES OF DISSOCIATED EMBRYONIC CHICK AND MOUSE CELLS. , 1957, Proceedings of the National Academy of Sciences of the United States of America.

[19]  G. Fleuren,et al.  Tumor structure and extracellular matrix as a possible barrier for therapeutic approaches using immune cells or adenoviruses in colorectal cancer , 2001, Histochemistry and Cell Biology.

[20]  P. Indovina,et al.  Multicellular tumour spheroids in radiation biology. , 1999, International journal of radiation biology.

[21]  V. Budach,et al.  Radioresponsiveness, sublethal damage repair and stem cell rate in spheroids from three human tumor lines: comparison with xenograft data. , 1992, International journal of radiation oncology, biology, physics.