Human-derived colorectal cancer organoids in microphysiological system to study radiotherapy

The second biggest cause of cancer-related fatalities globally is colorectal cancer (CRC). Currently external radiation, chemotherapy and surgery are the principal standard therapies for CRC. Due to the lack of distinctive symptoms in the early stages, most CRC patients are found at an advanced stage with a poor prognosis, necessitating the search for novel diagnostic and therapeutic approaches. 

At SCK CEN, the Institute for Nuclear Medical Applications is using so-called NAMs (New Approach Methodologies) to more accurately reproduce human physiology and thereby enhance the human relevance of the models tested for preclinical evaluation. Patient-derived tumor organoids (PDTOs) are self-organizing three-dimensional structures that can be readily derived from fresh patient tumor specimens and therefore, closely resemble their corresponding tumor type at a multi-omics level. To more closely replicate the in vivo conditions of the disease, specifically the tumor microenvironment (TME), PDTOs are cultured using microphysiological systems (MPS) also kown as organ-on-a-chip technology. Using MPS, human cancer cells can be cultured in the chip microchannels and dynamic flow conditions can be incorporated, to produce a biomimetic cancer-on-a-chip model. 

Previous work at SCK CEN successfully implemented the cultivation and external irradiation of a commercially available PDTO, in both static and dynamic setups. The purpose of this project is to start from another PDTO and follow the same procedure as previously established, to assess the diversity and the reproducibility of the PDTO models. After achieving successful cell production, the new PDTO will differentiate in monolayers that will be further cultivated in both static and dynamic conditions using the PhysioMimix MPS from CN Bio. PDTO monolayers will be exposed to radiation using a radiotherapy setup at doses relevant to cancer treatment. The impact of ionizing radiation on barrier integrity, cellular toxicity and global protein expression will be assessed using transepithelial electrical resistance (TEER), lactate dehydrogenase (LDH) cytotoxicity assay and high-throughput proteomics respectively. PDTO will also be daily monitored using microscopy techniques. This work will path the way for future applications of PDTOs in MPS for new cancer therapies evaluation.