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The XIII Banff meeting, held in conjunction the Canadian Society of Transplantation in Vancouver, Canada, reviewed the clinical impact of updates of C4d‐negative antibody‐mediated rejection (ABMR) from the 2013 meeting, reports from active Banff Working Groups, the relationships of donor‐specific antibody tests (anti‐HLA and non‐HLA) with transplant histopathology, and questions of molecular transplant diagnostics. The use of transcriptome gene sets, their resultant diagnostic classifiers, or common key genes to supplement the diagnosis and classification of rejection requires further consensus agreement and validation in biopsies. Newly introduced concepts include the i‐IFTA score, comprising inflammation within areas of fibrosis and atrophy and acceptance of transplant arteriolopathy within the descriptions of chronic active T cell–mediated rejection (TCMR) or chronic ABMR. The pattern of mixed TCMR and ABMR was increasingly recognized. This report also includes improved definitions of TCMR and ABMR in pancreas transplants with specification of vascular lesions and prospects for defining a vascularized composite allograft rejection classification. The goal of the Banff process is ongoing integration of advances in histologic, serologic, and molecular diagnostic techniques to produce a consensus‐based reporting system that offers precise composite scores, accurate routine diagnostics, and applicability to next‐generation clinical trials., In this article, the Banff consortium presents the most updated version of the kidney, pancreas, and VCA transplant rejection classification and prospects for implementing intragraft molecular assessment. See the companion report on page 42.

Matrix metalloproteinases (MMPs) are proteolytic enzymes important at several points during multistep neoplastic progression. Although MMP-1 and MMP-3 have been implicated in the progression of various human cancers, their expression in bladder cancer has not been addressed. Immunohistochemistry (Strept-ABC-HRP method) and in situ hybridization were performed to detect MMP-1 protein, MMP-3 protein, and MMP-3 mRNA, respectively, in 59 transitional cell bladder carcinomas. To assess the role of these MMPs in bladder cancer, their expression was evaluated in relation to known clinicopathologic parameters and patients’ disease-free and overall survival. Immunoreactivity for MMP-1 and MMP-3 proteins was observed in the cytoplasm of cancer cells in 30.5% and 24% of samples, respectively. Transcripts for MMP-3 mRNA were localized in stromal cells in 71.2% of cases and in cancer cells in 49% of cases. MMP-1 immunoreactivity demonstrated a statistically significant association with deeply invasive and grade III tumors versus superficial and lower grade tumors. MMP-3 protein immunoreactivity and MMP-3 mRNA immunolocalization did not associate with the parameters studied. However, MMP-3 mRNA localization in stromal cells demonstrated a borderline association with poor patients’ disease-free and overall survival. In conclusion, the authors’ results demonstrate a differential expression between MMP-1 and MMP-3 in bladder cancer; MMP-1 appears to participate in invasiveness and possibly in loss of differentiation in urothelial carcinomas in contrast to MMP-3.