Dr. Sabrina Marcazzan

My program "Experimental Imaging and Translational Microbiome Research" focuses on the development of microbiome-targeted imaging and theranostics wit the final goal to improve cancer diagnosis and therapy. In collaboration with researchers from the Medical School OWL, the Center of Biotechnology, the Faculties of Physics and Chemistry of Bielefeld University as well as national and international collaborators, we are identifying and studying potential imaging targets of tumor-microbiota and bacteria-bacteria interaction.

In recent times, the intratumoral microbiome has been emerged as the next pillar in cancer research, playing an increasingly relevant role in cancer development, progression and response to chemo- and immunotherapy. While targeted imaging has been developed to image several hallmarks of cancer, the intratumoral microbiota is poorly investigated. The use of bacteria specific-imaging has been limited to track tumor-targeting bacteria-based treatments or for imaging gut microbiota as a whole and an in vivo non-invasive monitoring of the intratumoral microbiota has not yet been developed. By combining experimental molecular imaging, translational oncology and microbiology, my long-term goal is to establish microbiome-targeted imaging as a new paradigm for precision cancer medicine.

Microbiome-derived markers in breast and colon cancer
Bacteria-derived products including metabolites, outer membrane vesicles (OMVs) and membrane vesicles (MVs) and other small molecules are involved in bacteria-bacteria communication, bacterial competition and colonization and could provide a readout for tumor-microbiome interaction in addition to gold standard 16S rRNA microbiome sequencing. In the ColoBIOTA project, we aim to characterize OMVs and MVs and the spatial organization of bacteria in colorectal cancer using new methods such as MALDI mass spectrometry, metaFISH, super-resolution microscopy methods, cryo-TEM in collaboraton with researchers from the Medical School OWL, Faculty of Physics , and Faculty of Chemistry, Bielefeld University. Such characterization of OMVs and MVs will provide insights into the role of the intratumoral microbiome on the development of colorectal cancer and in the future enable the development of novel therapeutic strategies.

Experimental imaging of tumor microbiome
Proof-of concept imaging studies in relevant in vitro models (e.g, patient-derived organoid cultures) and preclinical mouse models of cancer are pivotal to validate novel imaging methods and identify ones with high potential for clinical translation. Building on previous work performed at the Institute of Biological and Medical Imaging, Helmholtz Zentrum München on mouse- and patient-derived organoids and imaging in clinically relevant mouse models, I combine the evaluation of potential microbiome-specific imaging targets in patients with preclinical validation of target-specific molecular probes in vitro and in vivo. After identification of interested OMVs and MVs or small molecules, those will be labelled with different fluorescent dyes and their specificity for the bacteria of interests will be validated in spheroid and organoid cocultures models. In Bielefeld we are building a new core facility for small animal imaging and I am involved in its scientific development by organizing scientific workshops and establishing networks with national and international small animal imaging centers.

Microbiome-Micronanoplastic Interaction
Nano/micro/plastic particles (NMPs) are massively present in the environment, in foods, drinks, and cosmetics. The increasing and reported exposure to NMPs in humans poses questions about possible threats to human health. Presence of NMPs in human tissues and organs has been reported as well as possible negative effects on healthy gut microbiota and the host following NMPs ingestion. However, the extent to which NMPs may affect the gut microbiota and potential development of colon cancer is largely unknown. In the PlastBAC project, we are studying the effect of environmentally relevant Polymethylmethacrylat (PMMA) nanoparticles (Faculty of Chemistry and Medical School OWL) in relevant intestinal bacteria and spheroid coculture models with intestinal bacteria, including probiotic strains such as "Escherichia coli Nissle" and "Lactobacillus spp.". In cooperation with other researchers at the Medical School OWL, we will additionally analyze the effect of PMMA nanoparticles in the intestine of the invertebrate model "Caenorhabditis elegans". Our goal is to use these methods to unravel the potential impact of NMPs on tumor microbiome of the intestine as well as other cancer sites (e.g., the lung).

Prospective Master students and Dr. med. candidates interested in experimental imaging, cancer biology and tumor microbiome research are welcome to contact me.