N. Eberle

Comparison of examination of thoracic radiographs and thoracic computed tomography in dogs with appendicular osteosarcoma.

Appendicular osteosarcoma (OSA) is a highly metastatic tumour in dogs. The aim of the study was to compare thoracic radiographs with thoracic computed tomography (CT) in the staging of canine appendicular OSA. In all, 39 canine patients histologically diagnosed with OSA were reviewed in the retrospective study. All dogs underwent radiographic examination as well as CT examination of the thoracic cavity. Pulmonary nodules were detected radiographically in two cases (5%), whereas the CT imaging showed that pulmonary nodules were evident in 11 cases (28%, P = 0.024). There was an improved detection of small pulmonary nodules in the lung parenchyma with CT (P = 0.021). The number of nodules in CT examination had a significant negative influence on survival time (P = 0.005). However, whether nodules were present in CT or not did not influence overall survival (P = 0.368). CT examination was superior to thoracic radiography in the screening and detection of pulmonary nodules in dogs with OSA.

Cloning, characterisation, and comparative quantitative expression analyses of receptor for advanced glycation end products (RAGE) transcript forms

RAGE is a member of the immunoglobulin superfamily of cell surface molecules playing key roles in pathophysiological processes, e.g. immune/inflammatory disorders, Alzheimers disease, diabetic arteriosclerosis and tumourigenesis. In humans 19 naturally occurring RAGE splicing variants resulting in either N-terminally or C-terminally truncated proteins were identified and are lately discussed as mechanisms for receptor regulation. Accordingly, deregulation of sRAGE levels has been associated with several diseases e.g. Alzheimers disease, Type 1 diabetes, and rheumatoid arthritis. Administration of recombinant sRAGE to animal models of cancer blocked tumour growth successfully. In spite of its obvious relationship to cancer and metastasis data focusing sRAGE deregulation and tumours is rare. In this study we screened a set of tumours, healthy tissues and various cancer cell lines for RAGE splicing variants and analysed their structure. Additionally, we analysed the ratio of the mainly found transcript variants using quantitative Real-Time PCR. In total we characterised 24 previously not described canine and 4 human RAGE splicing variants, analysed their structure, classified their characteristics, and derived their respective protein forms. Interestingly, the healthy and the neoplastic tissue samples showed in majority RAGE transcripts coding for the complete receptor and transcripts showing insertions of intron 1.

HMGA1 and HMGA2 expression and comparative analyses of HMGA2, Lin28 and let-7 miRNAs in oral squamous cell carcinoma

BackgroundHumans and dogs are affected by squamous cell carcinomas of the oral cavity (OSCC) in a considerably high frequency. The high mobility group A2 (HMGA2) protein was found to be highly expressed in human OSCC and its expression was suggested to act as a useful predictive and prognostic tool in clinical management of oral carcinomas. Herein the expression of HMGA2 and its sister gene HMGA1 were analysed within human and canine OSCC samples. Additionally, the HMGA negatively regulating miRNAs of the let-7 family as well as the let-7 regulating gene Lin28 were also comparatively analysed. Deregulations of either one of these members could affect the progression of human and canine OSCC.MethodsExpression levels of HMGA1, HMGA2, Lin28, let-7a and mir-98 were analysed via relative qPCR in primary human and canine OSCC, thereof derived cell lines and non-neoplastic samples. Additionally, comparative HMGA2 protein expression was analysed by immunohistochemistry.ResultsIn both species, a significant up-regulation of the HMGA2 gene was found within the neoplastic samples while HMGA1 expression did not show significant deregulations. Comparative analyses showed down-regulation of mir-98 in human samples and up-regulation of let-7a and mir-98 in canine neoplastic samples. HMGA2 immunostainings showed higher intensities within the invasive front of the tumours than in the centre of the tumour in both species.ConclusionsHMGA2 could potentially serve as tumour marker in both species while HMGA1 might play a minor role in OSCC progression. Comparative studies indicate an inverse correlation of HMGA2 and mir-98 expression in human samples whereas in dogs no such characteristic could be found.

Flow cytometric evaluation of peripheral blood and bone marrow and fine-needle aspirate samples from multiple sites in dogs with multicentric lymphoma

OBJECTIVE To determine whether the extent of disease in dogs with lymphoma can be assessed via flow cytometry and to evaluate the suitability of fine-needle aspirates from the liver and spleen of dogs for flow cytometric examination. ANIMALS 44 dogs with multicentric B-cell (n = 35) or T-cell lymphoma (9) and 5 healthy control dogs. Procedures-Peripheral blood and bone marrow samples and fine-needle aspirates of lymph node, liver, and spleen were examined via flow cytometry. Logarithmically transformed T-cell-to-B-cell percentage ratio (log[T:B]) values were calculated. Thresholds defined by use of log(T:B) values of samples from control dogs were used to determine extranodal lymphoma involvement in lymphoma-affected dogs; results were compared with cytologic findings. RESULTS 12 of 245 (5%) samples (9 liver, 1 spleen, and 2 bone marrow) had insufficient cellularity for flow cytometric evaluation. Mean log(T:B) values of samples from dogs with B-cell lymphoma were significantly lower than those of samples from the same site in dogs with T-cell lymphoma and in control dogs. In dogs with T-cell lymphoma, the log(T:B) of lymph node, bone marrow, and spleen samples was significantly higher than in control dogs. Of 165 samples assessed for extranodal lymphoma involvement, 116 (70%) tested positive via flow cytometric analysis; results agreed with cytologic findings in 133 of 161 (83%) samples evaluated via both methods. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that flow cytometry may aid in detection of extranodal lymphoma involvement in dogs, but further research is needed. Most fine-needle aspirates of liver and spleen were suitable for flow cytometric evaluation.

Two new cases of polysomy 13 in canine prostate cancer.

Besides man, the dog is the only known mammalian species that spontaneously develops carcinomas of the prostate with considerable frequency. For this reason, the dog is considered to be the only useful animal model for spontaneously occurring prostate malignancies in man. Cytogenetic investigations of human prostate cancers have revealed the frequent occurrence of trisomies 7, 8, and 17. Chromosome analyses of canine prostate carcinomas are rare. In this report we present 2 cases of canine prostate cancer showing a clonal polysomy 13 along with complex karyotype changes. Along with a previous report demonstrating polysomy 13 as the only karyotype deviation in a canine prostate cancer the present report supports the hypothesis that in canine prostate cancer, polysomy 13 is a recurrent cytogenetic aberration linked to the development of the disease. As human chromosomes (HSA) 8q and 4q and the canine chromosome (CFA) 13 share high homology, these results suggest that a conserved area on these chromosomes is involved in tumorigenesis in both species.

High-mobility group B1 proteins in canine lymphoma: prognostic value of initial and sequential serum levels in treatment outcome following combination chemotherapy

Elevated high-mobility group box 1 (HMGB1) levels have been demonstrated in different human neoplasias. Information on serum HMGB1 before and during chemotherapy is lacking, as is data pertaining to its prognostic significance. The aim of this study was to characterize serum HMGB1 level in dogs with lymphoma and to assess its influence on the outcome following chemotherapy. Serum HMGB1 concentrations were measured in 16 dogs with lymphoma before treatment (W1) and on weeks 2 (W2), 6 (W6) and 12 (W12) of treatment with chemotherapy. Initial serum HMGB1 levels were significantly higher than HMGB1concentrations in control dogs and the levels in W2, W6 and W12. HMGB1-W1 concentrations were lower in dogs achieving complete remission than that in the single dog with partial remission. The ratio W12/W6 exhibited significant influence on remission duration. In these dogs with lymphoma, serum HMGB1 was elevated in comparison with that in controls. Initial serum HMGB1 level and its modulation during treatment may possess prognostic value.

Treatment of feline lymphoma using a 12-week, maintenance-free combination chemotherapy protocol in 26 cats

The aim of this prospective clinical trial was to investigate the efficacy and toxicity of a short-term, maintenance-free chemotherapy protocol in feline lymphoma. Twenty-six cats with confirmed diagnosis of high-/intermediate-grade lymphoma were treated with a 12-week protocol consisting of cyclic administration of l-asparaginase, vincristine, cyclophosphamide, doxorubicin and prednisolone. Complete (CR) and partial remission (PR) rates were 46 and 27%, respectively. Median duration of first CR was 394 days compared with a median PR duration of 41 days. No factor was identified to significantly influence the likelihood to reach CR. Overall survival amounted to 78 days (range: 9-2230 days). Median survival in CR cats was 454 days and in PR cats was 82 days. Toxicosis was mainly low grade with anorexia seen most frequently. In cats achieving CR, maintenance-free chemotherapy may be sufficient to attain long-term remission and survival. Factors aiding in prognosticating the likelihood for CR, strategies enhancing response and targeting chemotherapy-induced anorexia need to be identified in future.

Expression of the high mobility group A1 (HMGA1) and A2 (HMGA2) genes in canine lymphoma: analysis of 23 cases and comparison to control cases.

Overexpression of high mobility group A (HMGA) genes was described as a prognostic marker in different human malignancies, but its role in canine haematopoietic malignancies was unknown so far. The objective of this study was to analyse HMGA1 and HMGA2 gene expression in lymph nodes of canine lymphoma patients. The expression of HMGA1 and HMGA2 was analysed in lymph node samples of 23 dogs with lymphoma and three control dogs using relative quantitative real-time RT-PCR. Relative quantity of HMGA1 was significantly higher in dogs with lymphoma compared with reference samples. HMGA2 expression did not differ between lymphoma and control dogs. With the exception of immunophenotype, comparison of disease parameters did not display any differences in HMGA1 and HMGA2 expression. The present findings indicate a role of HMGA genes in canine lymphoma. This study represents the basis for future veterinary and comparative studies dealing with their diagnostic, prognostic and therapeutic values.

Splenic and hepatic ultrasound and cytology in canine lymphoma: effects of findings on stage migration and assessment of prognosis.

Stage migration is described in humans and dogs as a sequel of using more sensitive diagnostic methods. One hundred eighty-six dogs with multicentric lymphoma were enrolled with results of conventional staging as well as ultrasonographic and cytological examination of liver and spleen being available. The addition of splenic respective hepatic ultrasound and cytology findings resulted in slightly lower number of dogs classified as having liver and spleen involvement. In dogs with multicentric lymphoma, addition of cytology led to a significant shift of individuals from stage IV to stage III. Findings of hepatic and splenic ultrasound and cytology exerted no significant influence on complete remission and survival durations in dogs with combination chemotherapy. Staging methodology in canine lymphoma should be redefined, considering that the prognostic significance of splenic and hepatic ultrasound and cytology warrants further investigation.

Cytogenetic Analysis of CpG-Oligonucleotide DSP30 plus Interleukin-2-Stimulated Canine B-Cell Lymphoma Cells Reveals the Loss of One X Chromosome as the Sole Abnormality

Human and canine lymphoid neoplasms are characterized by non-random cytogenetic abnormalities. However, due to the low mitotic activity of the B cells, cytogenetic analyses of B-cell lymphoid proliferations are difficult to perform. In the present study we stimulated canine B-cell lymphoma cells with the immunostimulatory CpG-oligonucleotide DSP30 in combination with interleukin-2 (IL-2) and obtained an adequate number of metaphases. Cytogenetic analyses revealed the loss of one X chromosome as the sole cytogenetic aberration. Chromosome analysis of the corresponding blood showed a normal female karyotype. Monosomy X as the sole clonal chromosomal abnormality is found in human hematopoietic malignancies as well, thus the dog may serve as a promising animal model.