Research Group Episomal-Persistent DNA in Cancer- and Chronic Diseases
Dr. Timo Bund
Despite significant progress in cancer therapy, the lack of etiologic understanding in cancer causation and immunology, including synergistic (infectious) risk factors expected for >50% of cancers, limits current transfer from basic research to real-world application. As a continuation of the division of Harald zur Hausen, our group focuses on the interplay between Bovine Meat and Milk Factors (BMMF, more than 200 of such single-stranded, plasmid-like DNA elements are currently known) taken up by consumption of bovine nutrition products and the contribution to indirect induction of different types of cancer (pathologic model of ‘BMMF-induced zoonotic-linked, infectious, indirect carcinogenesis’) based on chronic inflammation (CI), induction of radicals and random DNA mutations. We also focus on BMMF in the context of chronic diseases of the human brain CNS. We apply both BMMF type-specific, ultrasensitive wet-lab as well as large-scale multi-omics in silico BMMF screening of publicly available DNA/RNA libraries to investigate the presence of BMMF as pathogenic risk factor in human cancer and in natural bio-reservoirs. In preclinical BMMF in vitro models, we test replication, transcription and expression of BMMF targets with the aim to generate and validate tools for BMMF detection and modulation of BMMF positivity.
More than 14 intensively-tested, DKFZ-built antibodies directed against a conserved BMMF protein (Rep) are used in streamlined, histochemical lab-based analysis pipelines in colorectal cancer (CRC), but also in lung, liver, pancreas and prostate cancer, amongst others, to assess diagnostic use and cancer-specific BMMF expression levels in CI-linked cancers and their (possible) inflammatory pre-cancer stages (e.g. diverticulitis, pancreatitis, non-alcoholic steatohepatitis (NASH), chronic obstructive pulmonary disease (COPD)). Causative contribution of BMMF to cancer, in particular to CRC, is assessed in histochemistry in a case vs. control and metric setup including pre-cancerous stages accessible via our broad clinical cooperation network. We combine it with additional protein-specific (immunoblotting and mass spectroscopy) and DNA/RNA-based readouts (qPCR/PCR, NGS, laser microdissection). In addition, we focus on the prognostic relevance of BMMF expression based on an immunoreactive BMMF score to evaluate BMMF expression in tumour and peritumour tissues and the associated outcome. We complement that with bulk as well as single-cell RNAseq large data analyses to test the effect of BMMF expression on the regulation of BMMF-positive macrophages to unravel the molecular and mechanistical background of BMMF-driven indirect carcinogenesis. This also includes the pro-tumourigenic modulation of the tumor microenvironment (TME) and therapy resistance, which might be supported by BMMF. We analyze the ultrastructure of BMMF targets (by immuno electron microscopy), which suggests a pleomorphic, vesicular presence of BMMF and accessibility for intervention - e.g. based on antibodies.
Our multi-omics read outs are steadily revised and expanded for new targets to unravel the role of BMMF in indirect carcinogenesis, which most likely represent one of the most common zoonotic-linked infections in humans. We expect a penetration of BMMF into 30-50% of current cancer cases and 40-60% of cancer deaths.
To foster cancer prevention based on BMMF technology, we analyze the effects of BMMF exposure in pre-clinical models (BMMF mouse model, cell (co-)culture models). Our vision is to establish early cancer diagnosis and systemic and/or BMMF antibody and immune cell therapy to reduce the burden of BMMF and to prevent/therapize BMMF-linked cancer.