Project Summary/Abstract: The primary goal of the Biospecimen/Pathology Core B is to facilitate translational research related to prostate tissue-based studies. The major functions of the core are to collect, annotate, provide quality control/quality assurance measures, develop standard operating procedures, catalog specimens within databases, improve operations, and test and implement new technologies for interrogating biomarkers in tissue-based studies. Core B has appropriate informatics capabilities for tracking biospecimens, as well as linkage to clinical follow-up data sets. For the majority of our specimens in the repository, the essential pathological, clinical and family history information is available. In addition, we utilize FFPE cell line tissue blocks from cells with known genetic features as well as cell line tissue microarray’s (TMAs); these serve as standardized reference specimens for biomarker validation studies. Core B has a well-established history of supplying tissues and their derivatives to multiple investigators, performing immunohistochemical workups and staining protocols, testing and implementing new immunohistochemical and in situ hybridization technologies, performing research on biospecimens to determine optimal methods for preparations of DNA, RNA and protein. New functions have been and are being further developed for laser capture microdissection of frozen metastatic prostate cancer biopsies for genomic studies, and of FFPE tissues for immune-oncology studies relevant to the Research Projects in the current SPORE application. These include implementation of HALO™ algorithms for quantifying AR and MYC as well as specific inflammatory cell types in tumors using singleplex and multiplex IHC and Digital Spatial Profiling for protein and high content RNA studies. The core has also collaborated with and shared tools and biospecimens with many other investigators both within and outside the SPORE program, both within our institution as well as a number of others throughout the country.