Non-invasive detection of orthotopic human lung tumors by microRNA expression profiling of mouse exhaled breath condensates and exhaled extracellular vesicles.

Aim: The lung is the second most frequent site of metastatic dissemination. Early detection is key to improving survival. Given that the lung interfaces with the external environment, the collection of exhaled breath condensate (EBC) provides the opportunity to obtain biological material including exhaled miRNAs that originate from the lung. Methods: In this proof-of-principal study, we used the highly metastatic MDA-MB-231 subline 3475 breast cancer cell line (LM-3475) to establish an orthotopic lung tumor-bearing mouse model and investigate non-invasive detection of lung tumors by analysis of exhaled miRNAs. We initially conducted miRNA NGS and qPCR validation analyses on condensates collected from unrestrained animals and identified significant miRNA expression differences between the condensates of lung tumor-bearing and control mice. To focus our purification of EBC and evaluate the origin of these differentially expressed miRNAs, we developed a system to collect EBC directly from the nose and mouth of our mice. Results: Using nanoparticle distribution analyses, TEM, and ONi super-resolution nanoimaging, we determined that human tumor EVs could be increasingly detected in mouse EBC during the progression of secondary lung tumors. Using our customizable EV-CATCHER assay, we purified human tumor EVs from mouse EBC and demonstrated that the bulk of differentially expressed exhaled miRNAs originate from lung tumors, which could be detected by qPCR within 1 to 2 weeks after tail vein injection of the metastatic cells. Conclusion: This study is the first of its kind and demonstrates that lung tumor EVs are exhaled in mice and provide non-invasive biomarkers for detection of lung tumors.

The importance of transformations for traceability - A case study of lamb and lamb products.

Vertical product information flow is important with regard to consumers' perceptions of the meat which they buy. When research and analysis of traceability is carried out it is often found that critical points where information is systematically lost are encountered in the transformations of the resources. This study describes how lamb meat can be both tracked and traced through a lamb meat producer (company A). At company A 60% of the resource transformations were shown to be additions, mixing and splitting, these are considered to be those which produce the most critical traceability points. After an analysis of the current traceability system at company A suggested improvements were made. With regard to granularity of traceability they cannot trace individual animals during production, but rather a set of animals. The smallest traceable resource unit (TRU) company A can trace back to be a set of (identifiable) animals from one specific farm.