Cellular atypia is negatively correlated with immunohistochemical reactivity of CD31 and vWF expression levels in canine hemangiosarcoma

Hepatic vascular hamartoma in a cat: a case report with literature review

Vascular hamartomas represent a focal proliferation of disorganized vascular tissue, which is usually present at birth. An 8-month-old Scottish fold female cat presented with abdominal distention, mild dyspnea, pale mucous membranes, and lethargy. Ultrasound examination revealed a hepatic mass resembling multiple cysts affecting the right medial lobe. Surgical excision was performed, and tissue samples were sent for histopathological evaluation. The mass was composed of multiple, dilated, variably-sized well-differentiated arterioles and venules, consistent with vascular hamartoma. Immunohistochemical investigation of the cells lining the cystic structures showed positive immunolabeling for vimentin and negative immunolabeling for PanCK, supporting the histological diagnosis. Based on existing literature, this represents the first case of hepatic localization of vascular hamartoma in a cat. In addition, a comparative histological study between vascular hamartoma and biliary duct hamartoma and a review on hepatic vascular hamartomas in animals and hepatic cystic masses in cats was made.

Current understanding of comparative pathology and prospective research approaches for canine hemangiosarcoma

Hemangiosarcoma (HSA) is a malignant tumor originating from endothelial cells. HSA typically develops in dogs, but is rare in other animals, including humans. Although surgery and chemotherapy are conventional treatments for HSA, neither treatment can significantly improve patient prognosis. To develop novel and effective therapeutics, a deeper understanding of HSA pathogenesis must be acquired. However, the limited research tools for HSA have been unable to make a breakthrough; therefore, it is crucial to widely utilize or establish novel research tools such as patient-derived xenograft models, organoids, and chicken embryo xenograft models. The pathogenesis of the human counterpart of HSA, angiosarcoma (AS), also remains incompletely understood, preventing the extrapolation of findings from humans to dogs, unlike other diseases. In this review, we summarize the clinicopathological and morphological features of HSA, and then we discuss the current understanding of the molecular pathology of HSA. Finally, we highlight promising research tools that may accelerate HSA basic research toward developing novel therapeutics. We also briefly summarize AS to help researchers comprehend HSA from the perspective of comparative pathology.

Diverse genome-wide DNA methylation alterations in canine hepatocellular tumours

BACKGROUND

Canine hepatocellular tumours (HCTs) are common primary liver tumours. However, the exact mechanisms of tumourigenesis remain unclear. Although some genetic mutations have been reported, DNA methylation alterations in canine HCT have not been well studied.

OBJECTIVES

In this study, we aimed to analyse the DNA methylation status of canine HCT.

METHODS

Tissues from 33 hepatocellular carcinomas, 3 hepatocellular adenomas, 1 nodular hyperplasia, 21 non-tumour livers from the patients and normal livers from 5 healthy dogs were used. We analysed the DNA methylation levels of 72,367 cytosine-guanine dinucleotides (CpG sites) in all 63 samples.

RESULTS AND CONCLUSIONS

Although a large fraction of CpG sites that were highly methylated in the normal liver became hypomethylated in tumours from most patients, we also found some patients with less remarkable change or no change in DNA methylation. Hierarchical clustering analysis revealed that 32 of 37 tumour samples differed from normal livers, although the remaining 5 tumour livers fell into the same cluster as normal livers. In addition, the number of hypermethylated genes in tumour livers varied among tumour cases, suggesting various DNA methylation patterns in different tumour groups. However, patient and clinical parameters, such as age, were not associated with DNA methylation status. In conclusion, we found that HCTs undergo aberrant and diverse patterns of genome-wide DNA methylation compared with normal liver tissue, suggesting a complex epigenetic mechanism in canine HCT.

Analysis of the Prevalence of Canine Splenic Mass Lesions in Republic of Korea via Histopathological Diagnosis with Immunohistochemistry

The histopathological diagnosis of canine splenic mass lesions is crucial for prognostication. However, thus far, no study has been conducted on the histopathology of canine splenic mass lesions in Republic of Korea. Herein, the prevalence of splenic diseases was analyzed in 137 canine splenic mass lesions via histopathological diagnosis, and the microscopic pattern associated with each disorder was described. Immunohistochemistry was performed for CD31, CD3, PAX5, Iba1, and C-kit for a more accurate diagnosis of splenic tumors. The proportion of non-neoplastic disorders, including nodular hyperplasia (48.2%, n = 66) and hematoma (24.1%, n = 33), was 72.3%. Splenic tumors, including splenic hemangiosarcoma (10.2%, n = 14), splenic lymphoma (nodular and diffuse types, 8.0%, n = 11), splenic stromal sarcoma (7.3%, n = 10), myelolipoma (1.5%, n = 2), and mast cell tumors (0.7%, n = 1), accounted for 27.7% of cases. The results of this study will aid veterinary clinicians in communication with pet owners about prognoses, recommendations for splenectomy, and subsequent histopathological diagnoses. This study will facilitate further investigations with more detailed comparisons of splenic mass lesions between small- and large-breed dogs.

Histopathological Grading, Clinical Staging and CD 31 Expression of Canine Splenic Hemangiosarcoma

Canine hemangiosarcoma is a common, highly fatal tumor of older dogs, and predictors of survivability may provide clinically useful information. The objectives of this case series were to determine if a previously published tumor histological grading scheme, the level of tumor cellular atypia, clinical staging, or the level of CD 31 expression were useful for predicting the survival time in dogs with splenic hemangiosarcoma. Canine splenic hemangiosarcomas from 16 dogs were histologically graded, clinically staged, and assessed for CD 31 expression. Medical records were reviewed, the date of death was obtained, and survival data were analyzed statistically. Histopathological grading and clinical staging of canine splenic hemangiosarcomas, and the expression of CD 31 by the tumor cells were not significantly associated with the median survival time of the dogs in this study. However, strong expression of CD 31 by canine splenic hemangiosarcoma tumor cells was observed in dogs with short survival times, which warrants further studies to evaluate the potential prognostic value of CD 31 expression for the survival of dogs with splenic hemangiosarcoma.

Hemorrhage and Sudden Death in a Cat with Pancreatic Hemangiosarcoma

A 15-year-old female, indoor, spayed, domestic shorthair cat was presented for post-mortem evaluation with a history of sudden death. A red-brown 3 cm x 4 cm neoplastic mass was identified within the body of the pancreas, along with multiple similar nodular structures within the omentum and liver. Associated lesions included hemoperitoneum, yellow discoloration of the peritoneal wall, and severe anemia. Spindle-shaped neoplastic cells exhibiting malignancy features, which occasionally contained within the cytoplasm haematoidin crystals and/or red blood cells, were observed during cytological examination. Histologically, the neoplastic cells were organized in short streams forming vascular spaces filled with erythrocytes. Immunohistochemically, the neoplastic cells were immunolabeled for vimentin and CD31, supporting the diagnosis of hemangiosarcoma. This report offers a complete post-mortem and histological evaluation of a rare tumor in cats with an unusual location and a comparative assessment of 3 anti-CD31 antibodies.

Safety Assessment of Ultrasound-Assisted Intravesical Chemotherapy in Normal Dogs: A Pilot Study

Intravesical chemotherapy after transurethral resection is a treatment option in patients with non-muscle invasive bladder cancer. The efficacy of intravesical chemotherapy is determined by the cellular uptake of intravesical drugs. Therefore, drug delivery technologies in the urinary bladder are promising tools for enhancing the efficacy of intravesical chemotherapy. Ultrasound-triggered microbubble cavitation may enhance the permeability of the urothelium, and thus may have potential as a drug delivery technology in the urinary bladder. Meanwhile, the enhanced permeability may increase systemic absorption of intravesical drugs, which may increase the adverse effects of the drug. The aim of this preliminary safety study was to assess the systemic absorption of an intravesical drug that was delivered by ultrasound-triggered microbubble cavitation in the urinary bladder of normal dogs. Pirarubicin, a derivative of doxorubicin, and an ultrasound contrast agent (Sonazoid) microbubbles were administered in the urinary bladder. Ultrasound (transmitting frequency 5 MHz; pulse duration 0.44 μsec; pulse repetition frequency 7.7 kHz; peak negative pressure −1.2 MPa) was exposed to the bladder using a diagnostic ultrasound probe (PLT-704SBT). The combination of ultrasound and microbubbles did not increase the plasma concentration of intravesical pirarubicin. In addition, hematoxylin and eosin staining showed that the combination of ultrasound and microbubble did not cause observable damages to the urothelium. Tissue pirarubicin concentration in the sonicated region was higher than that of the non-sonicated region in two of three dogs. The results of this pilot study demonstrate the safety of the combination of intravesical pirarubicin and ultrasound-triggered microbubble cavitation, that is, ultrasound-assisted intravesical chemotherapy.

KDM2B promotes cell viability by enhancing DNA damage response in canine hemangiosarcoma

Epigenetic regulators have been implicated in tumorigenesis of many types of cancer; however, their roles in endothelial cell cancers such as canine hemangiosarcoma (HSA) have not been studied. In this study, we find that lysine-specific demethylase 2b (KDM2B) is highly expressed in HSA cell lines compared with normal canine endothelial cells. Silencing of KDM2B in HSA cells results in increased cell death in vitro compared with the scramble control by inducing apoptosis through the inactivation of the DNA repair pathways and accumulation of DNA damage. Similarly, doxycycline-induced KDM2B silencing in tumor xenografts results in decreased tumor sizes compared with the control. Furthermore, KDM2B is also highly expressed in clinical cases of HSA. We hypothesize that pharmacological KDM2B inhibition can also induce HSA cell death and can be used as an alternative treatment for HSA. We treat HSA cells with GSK-J4, a histone demethylase inhibitor, and find that GSK-J4 treatment also induces apoptosis and cell death. In addition, GSK-J4 treatment decreases tumor size. Therefore, we demonstrate that KDM2B acts as an oncogene in HSA by enhancing the DNA damage response. Moreover, we show that histone demethylase inhibitor GSK-J4 can be used as a therapeutic alternative to doxorubicin for HSA treatment.

Candidate Glycoprotein Biomarkers for Canine Visceral Hemangiosarcoma and Validation Using Semi-Quantitative Lectin/Immunohistochemical Assays

Visceral hemangiosarcoma (HSA) is one of the more frequent cancers in dogs and has a high metastatic rate and poor prognosis, as clinical signs only become apparent in advanced stages of tumor development. In order to improve early and differential diagnostic capabilities and hence, prognosis for dogs with HSA, two types of biomarker are needed: a point-of-care diagnostic biomarker and a prognostic biomarker—preferentially based on samples obtained with minimally invasive methods. In this study, we applied a lectin magnetic bead array-coupled tandem mass spectrometry (LeMBA-MS/MS) workflow through discovery and validation phases to discover serum glycoprotein biomarker candidates for canine HSA. By this approach, we found that Datura stramonium (DSA), wheat germ agglutinin (WGA), Sambucus nigra (SNA), and Pisum sativum (PSA) lectins captured the highest number of validated candidate glycoproteins. Secondly, we independently validated serum LeMBA-MS/MS results by demonstrating the in situ relationship of lectin-binding with tumor cells. Using lectin-histochemistry and immunohistochemistry (IHC) for key proteins on tissues with HSA and semi-quantitation of the signals, we demonstrate that a combination of DSA histochemistry and IHC for complement C7 greatly increases the prospect of a more specific diagnosis of canine HSA.

Intracerebral Hemorrhage Induced Brain Injury Is Mediated by the Interleukin-12 Receptor in Rats

BACKGROUND

IL-12 inhibition of the endothelial cell functions and angiogenesis is mediated by the cross-talk between the lymphocyte and the endothelial cells, which plays a key role in inhibiting the process of angiogenesis in the eyeballs and in malignant tumors.

METHODS

We established the intracerebral hemorrhage (ICH) rat model, and IL-12 receptor beta monoclonal antibody was injected into the ICH rats. Western blot, immunofluorescence and RT-qPCR were used to detect the gene expression. Brain water content, EB staining, Garcia test, Beam walking test and wire hanging test were used to assess the injury of brain in ICH rats.

RESULTS

IL-12 gene was significantly increase in hematoma border tissue of ICH rats, and IL-12 protein mainly localized in monocytes. Anti-IL-12 treatment with IL-12 monoclonal antibodies could not only significantly decrease the brain water content and EB content in brain tissues of ICH rats, but also significantly increase the score of the Garcia, Beam balance and the Wire hanging test in ICH rats. Moreover, anti-IL-12 treatment significantly decrease the expression of pro-inflammatory gene, inflammatory gene, p-JAK2/JAK2 and p-STAT4/STAT4 protein, but significantly increase the expression anti-inflammatory gene and CD31 protein, and M2 macrophage ratio in hematoma border tissues of ICH rats. In vitro, rmIL-12 inhibited the tube formation of brain microvascular endothelial cells (BMVES) in BMVES and bone marrow-derived monocytes (BMDM) co-culture systems, but not work in a separately cultured BMVES system. In addition, Fedratinib not only reduced p-JAK2/JAK2 and p-STAT4/STAT4 protein expression in BMDM after treating with b-FGF and rmIL-12, but also significantly increased the tube formation of BMVES in BMVES and BMDM co-culture systems after treating with b-FGF and rmIL-12.

CONCLUSION

Blockade of IL-12 receptor attenuated brain injury after ICH in rat by promoting angiogenesis, and the mechanism might be related to blocking IL-12 could inhibit M2 cell activation via the JAK2/STAT4 pathway.

Expression of Hematopoietic Stem and Endothelial Cell Markers in Canine Hemangiosarcoma

Several chemicals and pharmaceuticals increase the incidence of hemangiosarcomas (HSAs) in mice, but the relevance to humans is uncertain. Recently, canine HSAs were identified as a powerful tool for investigating the pathogenesis of human HSAs. To characterize the cellular phenotype of canine HSAs, we evaluated immunoreactivity and/or messenger RNA (mRNA) expression of markers for hematopoietic stem cells (HSCs), endothelial cells (ECs), a tumor suppressor protein, and a myeloid marker in canine HSAs. Neoplastic canine cells expressed EC markers and a myeloid marker, but expressed HSC markers less consistently. The canine tumor expression results were then compared to previously published immunoreactivity results for these markers in human and mouse HSAs. There are 2 noteworthy differences across species: (1) most human HSAs had HSC marker expression, indicating that they were comprised of tumor cells that were less differentiated than those in canine and mouse tumors; and (2) human and canine HSAs expressed a late-stage EC maturation marker, whereas mouse HSAs were negative, suggesting that human and canine tumors may retain greater differentiation potential than mouse tumors. These results indicate that HSA development is variable across species and that caution is necessary when discussing translation of carcinogenic risk from animal models to humans.

Spontaneous abdominal hemangiosarcoma in a ferret

Herein, we describe the case of a 6-year-old female ferret that died within a few days of the onset of anorexia and reduced spontaneous locomotor activity. Necropsy revealed a dark red abdominal mass of unknown origin between the right lobes of the pancreas and the proximal jejunum, with massive blood retention in the peritoneal cavity. Histopathologically, spindle-shaped or sometimes polygonal tumor cells were proliferating with irregularly shaped vascular spaces containing blood components and surrounding-tissue infiltration. In some areas, tumor cells formed distinctly dilated blood vessel-like structures. Immunohistochemically, most of the tumor cells were strongly positive for CD31, but factor VIII-related antigen immunoreactivity was confined to the area with dilated blood vessel-like structures. Based on these findings, the tumor was diagnosed as an abdominal hemangiosarcoma. Abdominal hemangiosarcoma excluding cases of the liver and spleen are rare in ferrets.

Notch2 signal is required for the maintenance of canine hemangiosarcoma cancer stem cell-like cells

Background

Hemangiosarcoma (HSA) is a malignant tumor derived from endothelial cells which usually shows poor prognosis due to its high invasiveness, metastatic rate and severe hemorrhage from tumor ruptures. Since the pathogenesis of HSA is not yet complete, further understanding of its molecular basis is required.

Results

Here, we identified Notch2 signal as a key factor in maintaining canine HSA cancer stem cell (CSC)-like cells. We first cultured HSA cell lines in adherent serum-free condition and confirmed their CSC-like characteristics. Notch signal was upregulated in the CSC-like cells and Notch signal inhibition by a γ-secretase inhibitor significantly repressed their growth. Notch2, a Notch receptor, was highly expressed in the CSC-like cells. Constitutive activation of Notch2 increased clonogenicity and number of cells which were able to survive in serum-free condition. In contrast, inhibition of Notch2 activity showed opposite effects. These results suggest that Notch2 is an important factor for maintaining HSA CSC-like cells. Neoplastic cells in clinical cases also express Notch2 higher than endothelial cells in the normal blood vessels in the same slides.

Conclusion

This study provides foundation for further stem cell research in HSA and can provide a way to develop effective treatments to CSCs of endothelial tumors.

Electronic supplementary material

The online version of this article (10.1186/s12917-018-1624-8) contains supplementary material, which is available to authorized users.