The project’s premise is the development of novel genetics-based therapeutics, which are able to overcome tumor-associated escape mechanisms, particularly immune suppression in the tumor microenvironment. In a first step potential immune checkpoint candidates on the surface of selected tumor cells and various immune cell populations were characterized by gene expression studies and protein-targeted flow cytometry. Suitable in vitro test models could be established in order to evaluate the functionality of the novel gene therapeutics and several candidates could be examined for their effects by qPCR and flow cytometry. Identification of suitable target molecules on the surface of tumor cells is often restricted to specific tumor types. Thus, special focus was put on a particularly relevant solid tumor disease: malignant glioblastoma (GBM). GBM is a highly malignant brain tumor that is currently subject to a particularly high unmet need. GBM tops the list of cancer-related causes of death in children and the general public is aware of the suffering of numerous affected patients and their relatives in the recent past, e.g. Beau Biden, son of the current democratic US president, Joe Biden. Two strategies to identify suitable target molecules were applied. On one hand, the analysis of various relevant, publicly available data sets for protein and RNA information (TCGA database, Ivy Atlas, etc.) was carried out using a novel datamining strategy developed by the project researcher. By means of biostatistical software, an informed evaluation of harmonized data sets with regard to defined, therapeutically relevant criteria was possible (see figure: datamining strategy). The comprehensive evaluation of the available data sets initially led to the identification of two new candidate target molecules. The relevance of the two candidates was subsequently validated in further data sets and subsequently through laboratory tests. Based on an invention of the researcher, a process for production of off-the-shelf cellular anti-cancer therapeutics could be developed and proof of principle could be achieved (see figure: NK irradiation). A patent application was filed accordingly in cooperation with Fraunhofer FEP in Germany. Overall, two highly efficient genetically engineered cell therapies for treatment of malignant glioblastoma were developed during the project. Preclinical testing was initiated and showed promising results but remains to be validated in GMP/GLP compliant settings. Furthermore, a number of additional ligands potentially suitable as a basis for drug development schemes was also identified by varies approaches. Especially concerning target 1, a so far unknown GBM associated protein, mechanisms underlying this association are of interest and should also be elucidated in the future.
