ABSTRACT
Cellular adaptation to a hypoxic microenvironment is essential for tumour progression and is largely mediated by HIF-1α and hypoxia-regulated factors, including CXCR4, VEGF-A and GLUT-1. In human osteosarcoma, hypoxia is associated with resistance to chemotherapy as well as with metastasis and poor survival, whereas little is known about its role in canine osteosarcoma (cOSA). This study aimed primarily to evaluate the prognostic value of several known hypoxic markers in cOSA. Immunohistochemical analysis for HIF-1α, CXCR4, VEGF-A and GLUT-1 was performed on 56 appendicular OSA samples; correlations with clinicopathological features and outcome was investigated. The second aim was to investigate the in vitro regulation of markers under chemically induced hypoxia (CoCl2). Two primary canine osteosarcoma cell lines were selected, and Western blotting, immunofluorescence and qRT-PCR were used to study protein and gene expression. Dogs with high-grade OSA (35.7%) were more susceptible to the development of metastases (P = 0.047) and showed high HIF-1α protein expression (P = 0.007). Moreover, HIF-1α overexpression (56%) was correlated with a shorter disease-free interval (DFI; P = 0.01), indicating that it is a reliable negative prognostic marker. The in vitro experiments identified an accumulation of HIF-1α in cOSA cells after chemically induced hypoxia, leading to a significant increase in GLUT-1 transcript (P = 0.02). HIF-1α might be a promising prognostic marker, highlighting opportunities for the use of therapeutic strategies targeting the hypoxic microenvironment in cOSA. These results reinforce the role of the dog as a comparative animal model since similar hypoxic mechanisms are reported in human osteosarcoma.
Subject(s)
Bone Neoplasms/veterinary , Cell Hypoxia/physiology , Dog Diseases/physiopathology , Hypoxia-Inducible Factor 1, alpha Subunit/genetics , Hypoxia-Inducible Factor 1, alpha Subunit/physiology , Osteosarcoma/veterinary , Animals , Biomarkers, Tumor/analysis , Bone Neoplasms/chemistry , Bone Neoplasms/physiopathology , Cell Line, Tumor , Dog Diseases/pathology , Dogs , Female , Gene Expression Regulation, Neoplastic , Glucose Transporter Type 1/analysis , Hypoxia-Inducible Factor 1, alpha Subunit/analysis , Immunohistochemistry/veterinary , Male , Neoplasm Metastasis/physiopathology , Osteosarcoma/chemistry , Osteosarcoma/physiopathology , Prognosis , Receptors, CXCR4/analysis , Vascular Endothelial Growth Factor A/analysisABSTRACT
Ki67 can discriminate between high- and low-grade canine lymphomas, but its prognostic role in specific subtypes of the neoplasm is unknown. We assessed the prognostic significance of Ki67% (percentage of Ki67-positive cells), evaluated by flow cytometry, in 40 dogs with high-grade B-cell lymphoma, treated with a modified Wisconsin-Madison protocol (UW-25). The following variables were investigated for association with lymphoma specific survival (LSS) and relapse free interval (RFI): Ki67%, breed, sex, age, stage, substage, complete remission (CR). By multivariate analysis, Ki67% (P = 0.009) and achievement of CR (P = 0.001) were independent prognostic factors for LSS. Dogs with intermediate Ki67% (20.1-40%) presented longer LSS and RFI (median = 866 and 428 days, respectively) than dogs with low (median = 42 days, P < 0.001; median = 159 days, P = 0.014) or high (median = 173 days, P = 0.038; median = 100 days, P = 0.126) values. Determination of Ki67 is a prognostic tool that improves the clinical usefulness of flow cytometric analysis in canine high-grade B-cell lymphoma.
Subject(s)
Dog Diseases/diagnosis , Flow Cytometry/veterinary , Ki-67 Antigen/blood , Lymphoma, B-Cell/veterinary , Animals , Dog Diseases/blood , Dog Diseases/drug therapy , Dog Diseases/mortality , Dogs , Female , Flow Cytometry/methods , Lymphoma, B-Cell/blood , Lymphoma, B-Cell/diagnosis , Lymphoma, B-Cell/drug therapy , Male , Prognosis , Survival AnalysisABSTRACT
Canine malignant melanoma (CMM) is the most common canine oral tumour, and up to 70-75% of dogs in stage II-III die within 1 year after surgery. The purpose of this study was to evaluate the expression of platelet-derived growth factors receptors (PDGFR)-α and -ß in stage II and III CMMs and to correlate it with prognosis. PDGFRs expression was evaluated by immunohistochemistry on 48 cases of formalin-fixed CMM samples and correlated with clinical-pathological findings and outcome after surgery. PDGFRs co-expression was observed in 37.5% of cases. Positivity for PDGFR-α and -ß receptor was present in 54.2 and 47.9% of cases, respectively. Ki67 values >19.5% were ascertained in 66.7% of cases. Statistical analysis showed that PDGFRs co-expression and Ki67 values > 19.5% were both associated with worse prognosis. PDGFRs expression suggests a role in the pathogenesis and progression of CMM, and α and ß co-expression appears to be associated to worse prognosis.
Subject(s)
Dog Diseases/metabolism , Melanoma/veterinary , Mouth Neoplasms/veterinary , Receptors, Platelet-Derived Growth Factor/metabolism , Animals , Dog Diseases/diagnosis , Dog Diseases/mortality , Dogs , Female , Gene Expression Regulation, Neoplastic , Male , Melanoma/diagnosis , Melanoma/metabolism , Melanoma/mortality , Mouth Neoplasms/diagnosis , Mouth Neoplasms/metabolism , Mouth Neoplasms/mortality , Prognosis , Receptor, Platelet-Derived Growth Factor alpha/metabolism , Receptor, Platelet-Derived Growth Factor beta/metabolism , Survival AnalysisABSTRACT
Reported post-surgery 1-year survival rate for oral canine malignant melanoma (cMM) is around 30%; novel treatments are needed as the role of adjuvant chemotherapy is unclear. This prospective study regards adjuvant electrovaccination with human chondroitin sulfate proteoglycan-4 (hCSPG4)-encoded plasmid in 23 dogs with resected II/III-staged CSPG4-positive oral cMM compared with 19 dogs with resected only II/III-staged CSPG4-positive oral cMM. Vaccination resulted in 6-, 12-, 18- and 24-month survival rate of 95.6, 73.9, 47.8 and 30.4%, respectively [median survival time (MST) 684 days, range 78-1694, 8 of 23 dogs alive] and 6-, 12-, 18- and 24-month disease-free interval (DFI) rate of 82.6, 47.8, 26.1 and 17.4%, respectively (DFI 477 days, range 50-1694). Non-vaccinated dogs showed 6-, 12-, 18- and 24-month survival rate of 63.2, 26.3, 15.8 and 5.3%, respectively (MST 200 days, range 75-1507, 1 of 19 dogs alive) and 6-, 12-, 18- and 24-month DFI rate of 52.6, 26.3, 10.5 and 5.3%, respectively (DFI 180 days, range 38-1250). Overall survival and DFI of vaccinated dogs was longer in those <20 kg. In vaccinated and non-vaccinated dogs local recurrence rate was 34.8 and 42%, respectively while lung metastatic rate was 39 and 79%, respectively.
Subject(s)
Chondroitin Sulfate Proteoglycans/immunology , Dog Diseases/therapy , Melanoma/veterinary , Mouth Neoplasms/veterinary , Adjuvants, Immunologic/therapeutic use , Animals , Cancer Vaccines/therapeutic use , Combined Modality Therapy , Dog Diseases/mortality , Dogs , Female , Male , Melanoma/mortality , Melanoma/therapy , Mouth Neoplasms/mortality , Mouth Neoplasms/therapyABSTRACT
The aim of this retrospective study was to describe clinical features, treatment and outcome of 21 dogs with metastatic cancer of unknown primary (MCUP), a biopsy-proven malignancy being diagnosed at a metastatic stage, in which the anatomical origin of the primary tumour cannot be detected. All dogs underwent total-body computed tomography. Signalment, type and duration of clinical signs, metastasis site, pathology results, treatment and outcome were recorded. Carcinoma was the most common diagnosis (57.1%), followed by sarcoma, melanoma and mast cell tumour. The median number of disease sites per dog was 2, with bones, lymph nodes, lungs and spleen being the most frequent metastatic locations. The median survival for all dogs was 30 days. Overall, a primary site was not identified in 20 (95.2%) dogs. MCUP encompasses a variety of different pathologic entities and harbours a poor prognosis.
