HISTOPATHOLOGY & TISSUE SHARED RESOURCE: PROJECT SUMMARY The Histopathology & Tissue Shared Resource (HTSR) is the Georgetown Lombardi Comprehensive Cancer Center (LCCC) resource for accessing human tissue for translational research and provides comprehensive, high-quality laboratory and interpretive pathology services. The HTSR collects and distributes fresh, frozen, and formalin-fixed, paraffin-embedded tissues and select biofluids from 15,440 patients; provides technical and pathology support for investigator-driven collection protocols; and offers complementary services to LCCC Members in DC and NJ. The facility is Co-Directed by Brent Harris, MD, PhD, who oversees services and provides comprehensive pathology services in DC, and David Kar-Fai Chow, MD, who oversees Hackensack Meridian Health’s (HMH) Biorepository (BioR) and provides comprehensive pathology services in NJ. The HTSR facilitates discovery and innovative cancer research by collecting and distributing high-quality, clinically annotated human tissue and liquid biospecimens for translational research projects across the Consortium. The DC facility also provides comprehensive histology services including tissue processing, paraffin and frozen section microtomy, staining, immunohistochemistry (including quantitative multiplex), immunofluorescence, as well as tissue microarray (TMA) construction, staining and interpretative analysis. Research consenting and specimen collection processes were revamped in NJ which has helped expand and diversify the biospecimen resources available to LCCC Members. The DC and NJ facilities provide clinicopathologic expertise that complements LCCC biomedical informatics services, clinical and pathology database search capabilities, consultation services, and educational support and training for users. In response to user surveys, investigator feedback, guidance from the HTSR Advisory Committee , and External Advisory Committee recommendations since the last CCSG review, the HTSR expanded services to include quantitative automated brightfield and immunofluorescence image analysis, immunophenotyping, miRNA in situ staining, enhanced tissue microarray (TMA) construction, and newly acquired molecular platforms to support spatial biology applications (RNAscope, Nanostring GeoMx, Akoya Phenocycler, and Standard Biotools IMC). The HTSR works cooperatively with the Genomics & Epigenomics SR, Tissue Culture & Biobanking SR, Survey Recruitment & Biospecimen Collection SR, and the Mass Spectrometry & Analytical Pharmacology SR to prepare human and animal model tissues and cultures for downstream molecular analyses. In FY2022 the HTSR provided services to 37 LCCC Members across all three Research Programs (15 Cancer Cell Biology Members, 20 Cancer Host Interactions Members, and 2 Cancer Prevention and Control Members). In the current project period, HTSR’s impact is demonstrated through support of 54 peer-reviewed publications, including 14 papers published in high-i...