PROJECT SUMMARY: CORE B The goal of this Program is to advance knowledge of pancreatic ductal adenocarcinoma (PDAC), a recalcitrant cancer with one of the highest rates of cachexia. Project 1 focuses on PDAC-induced circulating factors, including IL-6 and its soluble receptor (sIL6R), leading to wasting of the target tissues via activation of STAT3 and NF-kB in adipocytes and myofibers. Project 2 investigates IL-6 and NF-kB in the skeletal muscle microenvironment in PDAC cachexia, as well as NF-kB in the tumor microenvironment and its effects on macrophages. Project 3’s studies probe interactions of IL-6, STAT3, and NF-kB among tumor cells, fibroblasts, and macrophages in the tumor microenvironment. Together these studies will tackle both PDAC tumor biology and the metabolic havoc it creates for the patient. Core B will provide the Projects with unprecedented potential to interrogate the PDAC macroenvironment by providing 1) human clinical specimens to evaluate the translational potential of their findings, and 2) the capacity to carry out transcriptome profiling at the single cell level using single cell and single nucleus RNAseq in matched samples from patients with PDAC, and 3) dedicated support for advanced sequence analysis. In doing so, this Core addresses barriers that have historically limited research in PDAC and cancer cachexia. Very few studies have reported gene expression or histological endpoints in peripheral tissues in human cancer cachexia and even fewer in PDAC cachexia, and none have attempted to match analyses across tissues. As well, these pioneering studies at single cell resolution in the PDAC macroenvironment of mouse models and humans, carried out by investigators at the forefront of these technologies and analytical capabilities will enable the Projects to make groundbreaking discoveries while contributing novel, high resolution data to the field. The specific aims are to 1) Collect, store and distribute clinically annotated PDAC cachexia biospecimens. Clinical data and biospecimens will be collected from PDAC surgical patients at Indiana University Simon Comprehensive Cancer Center (IUSCCC) and from patients from the Danish PACTO Trial for centralized compliance, processing, and distribution. 2) Carry out a single nucleus (sn) RNAseq study of the human PDAC cachexia macroenvironment for all Projects. Muscle and adipose samples from IUSM general surgery patients with benign conditions and muscle, adipose and tumor samples from IUSCCC PDAC surgery patients with and without moderate cachexia will be processed to make single nuclei preparations. Batched samples will be subjected to snRNAseq to test specific hypotheses for each of Projects 1-3 and the overall program. 3) Provide advanced analysis of single cell (sc) and snRNAseq studies for all Projects. Core B will provide dedicated advanced analysis of the snRNAseq data from human specimens in Aim 2 for Projects 1- 3, and of sn or scRNAseq data from mice emanating from eac...