@article{GentschevAdelfingerJosupeitetal.2012, author = {Gentschev, Ivaylo and Adelfinger, Marion and Josupeit, Rafael and Rudolph, Stephan and Ehrig, Klaas and Donat, Ulrike and Weibel, Stephanie and Chen, Nanhai G. and Yu, Yong A. and Zhang, Qian and Heisig, Martin and Thamm, Douglas and Stritzker, Jochen and MacNeill, Amy and Szalay, Aladar A.}, title = {Preclinical Evaluation of Oncolytic Vaccinia Virus for Therapy of Canine Soft Tissue Sarcoma}, series = {PLoS One}, volume = {7}, journal = {PLoS One}, number = {5}, doi = {10.1371/journal.pone.0037239}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-129998}, year = {2012}, abstract = {Virotherapy using oncolytic vaccinia virus (VACV) strains is one promising new strategy for canine cancer therapy. In this study we describe the establishment of an in vivo model of canine soft tissue sarcoma (CSTS) using the new isolated cell line STSA-1 and the analysis of the virus-mediated oncolytic and immunological effects of two different Lister VACV LIVP1.1.1 and GLV-1h68 strains against CSTS. Cell culture data demonstrated that both tested VACV strains efficiently infected and destroyed cells of the canine soft tissue sarcoma line STSA-1. In addition, in our new canine sarcoma tumor xenograft mouse model, systemic administration of LIVP1.1.1 or GLV-1h68 viruses led to significant inhibition of tumor growth compared to control mice. Furthermore, LIVP1.1.1 mediated therapy resulted in almost complete tumor regression and resulted in long-term survival of sarcoma-bearing mice. The replication of the tested VACV strains in tumor tissues led to strong oncolytic effects accompanied by an intense intratumoral infiltration of host immune cells, mainly neutrophils. These findings suggest that the direct viral oncolysis of tumor cells and the virus-dependent activation of tumor-associated host immune cells could be crucial parts of anti-tumor mechanism in STSA-1 xenografts. In summary, the data showed that both tested vaccinia virus strains and especially LIVP1.1.1 have great potential for effective treatment of CSTS.}, language = {en} } @article{GentschevMuellerAdelfingeretal.2011, author = {Gentschev, Ivaylo and M{\"u}ller, Meike and Adelfinger, Marion and Weibel, Stephanie and Grummt, Friedrich and Zimmermann, Martina and Bitzer, Michael and Heisig, Martin and Zhang, Qian and Yu, Yong A. and Chen, Nanhai G. and Stritzker, Jochen and Lauer, Ulrich M. and Szalay, Aladar A.}, title = {Efficient Colonization and Therapy of Human Hepatocellular Carcinoma (HCC) Using the Oncolytic Vaccinia Virus Strain GLV-1h68}, series = {PLOS ONE}, volume = {6}, journal = {PLOS ONE}, number = {7}, doi = {10.1371/journal.pone.0022069}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-135319}, pages = {e22069}, year = {2011}, abstract = {Virotherapy using oncolytic vaccinia virus strains is one of the most promising new strategies for cancer therapy. In this study, we analyzed for the first time the therapeutic efficacy of the oncolytic vaccinia virus GLV-1h68 in two human hepatocellular carcinoma cell lines HuH7 and PLC/PRF/5 (PLC) in cell culture and in tumor xenograft models. By viral proliferation assays and cell survival tests, we demonstrated that GLV-1h68 efficiently colonized, replicated in, and did lyse these cancer cells in culture. Experiments with HuH7 and PLC xenografts have revealed that a single intravenous injection (i.v.) of mice with GLV-1h68 resulted in a significant reduction of primary tumor sizes compared to uninjected controls. In addition, replication of GLV-1h68 in tumor cells led to strong inflammatory and oncolytic effects resulting in intense infiltration of MHC class II-positive cells like neutrophils, macrophages, B cells and dendritic cells and in up-regulation of 13 pro-inflammatory cytokines. Furthermore, GLV-1h68 infection of PLC tumors inhibited the formation of hemorrhagic structures which occur naturally in PLC tumors. Interestingly, we found a strongly reduced vascular density in infected PLC tumors only, but not in the non-hemorrhagic HuH7 tumor model. These data demonstrate that the GLV-1h68 vaccinia virus may have an enormous potential for treatment of human hepatocellular carcinoma in man.}, language = {en} } @article{HeisigFrentzenBergmannetal.2011, author = {Heisig, Martin and Frentzen, Alexa and Bergmann, Birgit and Gentschev, Katharina Ivaylo and Hotz, Christian and Schoen, Christoph and Stritzker, Jochen and Fensterle, Joachim and Rapp, Ulf R. and Goebel, Werner}, title = {Specific antibody-receptor interactions trigger InlAB-independent uptake of Listeria monocytogenes into tumor cell lines}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-68705}, year = {2011}, abstract = {Background: Specific cell targeting is an important, yet unsolved problem in bacteria-based therapeutic applications, like tumor or gene therapy. Here, we describe the construction of a novel, internalin A and B (InlAB)-deficient Listeria monocytogenes strain (Lm-spa+), which expresses protein A of Staphylococcus aureus (SPA) and anchors SPA in the correct orientation on the bacterial cell surface. Results: This listerial strain efficiently binds antibodies allowing specific interaction of the bacterium with the target recognized by the antibody. Binding of Trastuzumab (Herceptin®) or Cetuximab (Erbitux®) to Lm-spa+, two clinically approved monoclonal antibodies directed against HER2/neu and EGFR/HER1, respectively, triggers InlABindependent internalization into non-phagocytic cancer cell lines overexpressing the respective receptors. Internalization, subsequent escape into the host cell cytosol and intracellular replication of these bacteria are as efficient as of the corresponding InlAB-positive, SPA-negative parental strain. This specific antibody/receptormediated internalization of Lm-spa+ is shown in the murine 4T1 tumor cell line, the isogenic 4T1-HER2 cell line as well as the human cancer cell lines SK-BR-3 and SK-OV-3. Importantly, this targeting approach is applicable in a xenograft mouse tumor model after crosslinking the antibody to SPA on the listerial cell surface. Conclusions: Binding of receptor-specific antibodies to SPA-expressing L. monocytogenes may represent a promising approach to target L. monocytogenes to host cells expressing specific receptors triggering internalization.}, subject = {Listeria monocytogenes}, language = {en} }