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Background: One bottleneck for adoptive T cell therapy (ACT) is recruitment of T cells into tumors. We hypothesized that combining tumor-specific T cells, modified with a marker antigen and a bispecific antibody (BiAb) that selectively recognizes transduced T cells and tumor cells would improve T cell recruitment to tumors and enhance therapeutic efficacy. Methods: SV40 T antigen-specific T cells from T cell receptor (TCR)-I-transgenic mice were transduced with a truncated human epidermal growth factor receptor (EGFR) as a marker protein. Targeting and killing by combined ACT and anti-EGFR-anti-EpCAM BiAb therapy was analyzed in C57Bl/6 mice (n = six to 12 per group) carrying subcutaneous tumors of the murine gastric cancer cell line GC8 (SV40+ and EpCAM+). Anti-EGFR x anti-c-Met BiAb was used for targeting of human tumor-specific T cells to c-Met+ human tumor cell lines. Differences between experimental conditions were analyzed using the Student's t test, and differences in tumor growth with two-way analysis of variance. Overall survival was analyzed by log-rank test. All statistical tests were two-sided. Results: The BiAb linked EGFR-transduced T cells to tumor cells and enhanced tumor cell lysis. In vivo, the combination of ACT and Biab produced increased T cell infiltration of tumors, retarded tumor growth, and prolonged survival compared with ACT with a control antibody (median survival 95 vs 75 days, P < .001). In human cells, this strategy enhanced recruitment of human EGFR-transduced T cells to immobilized c-Met and recognition of tyrosinase+ melanoma cells by TCR-, as well as of CEA+ colon cancer cells by chimeric antigen receptor (CAR)-modified T cells. Conclusions: BiAb recruitment of tumor-specific T cells transduced with a marker antigen to tumor cells may enhance efficacy of ACT

Scientific discoveries that provide strong evidence of antitumor effects in preclinical models often encounter significant delays before being tested in patients with cancer. While some of these delays have a scientific basis, others do not. We need to do better. Innovative strategies need to move into early stage clinical trials as quickly as it is safe, and if successful, these therapies should efficiently obtain regulatory approval and widespread clinical application. In late 2009 and 2010 the Society for Immunotherapy of Cancer (SITC), convened an "Immunotherapy Summit" with representatives from immunotherapy organizations representing Europe, Japan, China and North America to discuss collaborations to improve development and delivery of cancer immunotherapy. One of the concepts raised by SITC and defined as critical by all parties was the need to identify hurdles that impede effective translation of cancer immunotherapy. With consensus on these hurdles, international working groups could be developed to make recommendations vetted by the participating organizations. These recommendations could then be considered by regulatory bodies, governmental and private funding agencies, pharmaceutical companies and academic institutions to facilitate changes necessary to accelerate clinical translation of novel immune-based cancer therapies. The critical hurdles identified by representatives of the collaborating organizations, now organized as the World Immunotherapy Council, are presented and discussed in this report. Some of the identified hurdles impede all investigators; others hinder investigators only in certain regions or institutions or are more relevant to specific types of immunotherapy or first-in-humans studies. Each of these hurdles can significantly delay clinical translation of promising advances in immunotherapy yet if overcome, have the potential to improve outcomes of patients with cancer.

Die epitheliale-mesenchymale Transition (EMT) ist ein zentraler Mechanismus während der Embryogenese, der auch im Laufe der Tumorprogression in einigen Tumoren beobachtet werden kann. Diese Arbeit beschäftigt sich mit der Frage, ob eine EMT auch im Nierenzellkarzinom (RCC) nachweisbar ist und wenn ja, wie diese auf molekularer Ebene in vitro und in situ charakterisiert ist. Dazu wurde in situ die Expression von EMT-assoziierten Molekülen in unterschiedlichen RCC-Tumorsubtypen und Differenzierungsstufen auf Transkript- und Proteinebene untersucht. Des Weiteren wurde in vitro ein möglicher Einfluss auf den jeweiligen Phänotyp von RCC-Zelllinien durch potentielle EMT-Stimuli, RCC-Therapeutika, verschiedene Kulturbedingungen oder epigenetische Modulation beobachtet und inwieweit sich die immunologische Erkennung von mesenchymalen bzw. epithelialen RCC-Phänotypen durch nicht-MHC-restringierte Effektorzellen verändert., The epithelial-mesenchymal transition (EMT) is a central mechanism during embryogenesis which is also observed in several tumours in the course of tumour progression. This work deals with the question, if an EMT can also be observed in renal cell carcinoma (RCC) and if so, how it is characterised in vitro and in situ at the molecular level. For that purpose the expression of EMT associated molecules has been analysed in situ in different RCC tumour subtypes and gradings on transcript and protein level. Furthermore, the potential influence on the relative phenotype of RCC cell lines by EMT stimuli, RCC therapeutics, various culture conditions or epigenetic modulations has been evaluated as well as how genetic modulation of a rather mesenchymal to an epithelial phenotype impinges on immunorecognition by non MHC (major histocompatibility complex) restricted cytotoxic killer cells.