Search

Although chemotherapy using CHOP-based protocol induces remission in most cases of canine multicentric high-grade B-cell lymphoma (mhBCL), some cases develop early relapse during the first induction protocol. In this study, we examined the gene expression profiles of canine mhBCL before chemotherapy and investigated their associations with early relapse during the first whole CHOP-based protocol. Twenty-five cases of mhBCL treated with CHOP-based protocol as first induction chemotherapy were included in this study. Sixteen cases completed the first whole CHOPbased protocol without relapse (S-group), and nine developed relapse during the chemotherapy (R-group). RNA-seq was performed on samples from neoplastic lymph nodes. Differentially expressed genes (DEGs) were extracted by the comparison of gene expression profiles between S- and R-groups, and the differences in the expression levels of these genes were validated by RTqPCR. Extracted 179 DEGs included the genes related to chemokine CC motif ligand, T-cell receptor signaling pathway, and PD-L1 expression and PD-1 checkpoint pathway. We focused on chemokine CC motif ligand, and CCL4 was confirmed to be significantly downregulated in the R-group (P=0.039). We also focused on the genes related to T-cell signaling pathway, and CD3E (P=0.039), ITK (P=0.023), and LAT (P=0.023) genes were confirmed to be significantly upregulated in the R-group. The current results suggest that both changes in tumor cells and the interactions between tumor cells and immune cells are associated with the efficacy of the chemotherapy for first remission induction. [ABSTRACT FROM AUTHOR]

Nineteen cases of histiocytic sarcomas in Pembroke Welsh Corgi were examined histopathologically. Focal or multiple masses were detected in the lung or in regional lymph nodes, or in both lung and nodes. All neoplastic lesions had common histological features characterized by the proliferation of pleomorphic histiocytic cells combined with various inflammatory cells. Most of the pleomorphic neoplastic cells were immunopositive for human leukocyte antigen (HLA)-DR and Iba-1. The median survival time for all dogs was 133 days. In the present study, several prognostic factors, such as gender, age, single or multiple lesions, lymph node involvement at the time of diagnosis, surgical resection status and additional chemotherapy, were examined, although none of these factors approached statistical significance. Histiocytic sarcoma must be considered in the differential diagnosis of dogs with pulmonary masses, especially in the canine breed.