CD117 immunoexpression in canine mast cell tumours: correlations with pathological variables and proliferation markers

<p>Abstract</p> <p>Background</p> <p>Cutaneous mast cell tumours are one of the most common neoplasms in dogs and show a highly variable biologic behaviour. Several prognosis tools have been proposed for canine mast cell tumours, including histological grading and cell proliferation markers. CD117 is a receptor tyrosine kinase thought to play a key role in human and canine mast cell neoplasms. Normal (membrane-associated) and aberrant (cytoplasmic, focal or diffuse) CD117 immunoexpression patterns have been identified in canine mast cell tumours. Cytoplasmic CD117 expression has been found to correlate with higher histological grade and with a worsened post-surgical prognosis. This study addresses the role of CD117 in canine mast cell tumours by studying the correlations between CD117 immunoexpression patterns, two proliferation markers (Ki67 and AgNORs) histological grade, and several other pathological variables.</p> <p>Results</p> <p>Highly significant (p < 0,001) correlations were found between CD117 immunostaining patterns and histological grade, cell proliferation markers (Ki67, AgNORs) and tumoral necrosis. Highly significant (p < 0,001) correlations were also established between the two cellular proliferation markers and histological grade, tumour necrosis and epidermal ulceration. A significant correlation (p = 0.035) was observed between CD117 expression patterns and epidermal ulceration. No differences were observed between focal and diffuse cytoplasmic CD117 staining patterns concerning any of the variables studied.</p> <p>Conclusion</p> <p>These findings highlight the key role of CD117 in the biopathology of canine MCTs and confirm the relationship between aberrant CD117 expression and increased cell proliferation and higher histological grade. Further studies are needed to unravel the cellular mechanisms underlying focal and diffuse cytoplasmic CD117 staining patterns, and their respective biopathologic relevance.</p

GASTRIC CARCINOMA WITH OSSEOUS METAPLASIA IN A DOG

This report describes an unprecedented case of a gastric carcinoma with osseous metaplasia in a 8-year-old male standard poodle. An exploratory laparotomy revealed a firm yellowish nodular mass in the pyloric region. The lesion was surgically removed and submitted for current histological examination. Immunohistochemistry was performed employing monoclonal antibodies for pan-cytokeratin, vimentin, smooth muscular a-actin and BMP-2/4. The mass consisted in neoplastic proliferation of epithelial cells, arranged in a tubular or acinar pattern and supported by scirrhous stroma, with mucin production and multiple foci of heterotopic ossification. Neoplastic epithelial cells showed strong positive immunostaining for AE1/AE3 and BMP-2/4, although they were negative for both vimentin and a-actin. Histopathological findings suggested that the bone tissue may be primarily originated from neoplastic epithelial cells which directly circumscribe the osseous metaplasia foci

MicroRNA-21 expression and susceptibility to HPV-induced carcinogenesis - role of microenvironment in K14-HPV16 mice model

Aims: Human papillomaviruses (HPVs) are responsible for several types of cancer. K14-HPV16 transgenic mice express the HPV16 early genes, developing multi-step carcinogenesis associated with marked inflammation, as observed in human patients. MicroRNAs (MiRNA) constitute a class of non-coding RNAs that regulate gene expression. In particular, miR-21 has been associated with carcinogenesis. However, little is known about this microRNA in the normal tissue microenvironment and its possible relationship with cancer predisposition. We hypothesized that miR-21 expression influences each tissue's susceptibility to HPV-induced carcinogenesis. Main methods: In order to test this hypothesis, we evaluated miR-21 expression by RT-qPCR in ear and chest skin samples from 24-28 weeks old, female K14-HPV16 transgenic and wild-type mice. Key findings: In wild-type mice (HPV-/-) miR-21 expression was lower in ear skin compared with that of chest skin (p = 0.036). Under the influence of HPV16 oncogenes, transgenic animals (HPV16+/-), developed in situ carcinoma in all ear samples and epidermal hyperplasia in chest samples. These results are consistent with the hypothesis that microRNA expression in the microenvironment of normal tissues may influence HPV-associated carcinogenesis. Furthermore, among transgenic animals, miR-21 expression was lower in in situ carcinoma samples compared with hyperplasia (p = 0043). Significance: This suggests that, despite the well-known role of miR-21 as an oncogene, its anti-inflammatory and immunomodulatory properties may modulate HPV-induced carcinogenesis in a tissue-dependent manner. Further studies are warranted in order to explore the role of microRNAs in tissue susceptibility to carcinogenesis

In vivo biocompatibility and biodegradability of dextrin-based hydrogels

The in vivo biocompatibility of dextrin hydrogels obtained by polymerization of dextrin-hydroxyethylmethacrylate (dextrin-HEMA) and dextrin-vinyl acrylate (dextrin-VA) are reported in this work. The histological analysis of subcutaneous implants of these hydrogels, featuring inflammatory and reabsorption events, were carried out over a 16-week period in mice. The dextrin-HEMA hydrogel was quickly and completely degraded and reabsorbed, whereas the dextrin-VA degradation occurred slowly and a thin fibrous capsule surrounded the nondegradable hydrogel. The dextrin-HEMA was degraded after 16 weeks with only mild inflammation and a few detectable foamy macrophages around the implant. These events were followed by complete resorption and no sign of capsule formation or fibrosis associated to the implants. The results indicate that the dextrin hydrogels are biocompatible because no toxicity on the tissues surrounding the implants was found. It may be speculated that a controlled degradation rate of the hydrogels may be obtained by grafting dextrin to HEMA and VA in different proportions.Funding from FCT through POCTI program is acknowledged. The authors Susana Moreira and Rui M. Gil da Costa are recipients of a PhD fellowship from Fundacao para a Ciencia e a Tecnologia (FCT, Portugal)

In situ synthesis of magnetite nanoparticles in carrageenan gels

Magnetite nanoparticles have been successfully synthesized in the presence of carrageenan polysaccharides using an in situ coprecipitation method. Iron coordination to the sulfate groups of the polysaccharide was confirmed by FTIR. The polysaccharide type ( , é, or ì) and concentration have been varied and their effects on particle morphology and chemical stability of the resultant nanocomposite investigated. The presence of carrageenan induces the formation of smaller particles, compared to those formed in the absence of polymer, and their average size depends on the nature and concentration of the polysaccharide used. The chemical stability of magnetite nanoparticles toward oxidation was also seen to depend on biopolymer type with magnetite formed in é-carrageenan showing the highest chemical stability. A general tendency toward lower stability is observed as the polysaccharide concentration is increased. It is suggested that magnetite chemical stability in the carrageenan composites is determined by a fine balance between particle size and gel strength, the latter determining oxygen diffusion rates through the medium

Cytokeratin 7/19 expression inN-diethylnitrosamine-induced mouse hepatocellular lesions: implications for histogenesis International

Hepatocellular carcinoma (HCC) is a common malignancy with poor clinical outcome, whose histogenesis is the subject of intense debate. Specifically, expression ofcytokeratins (CKs) 7 and 19, associated with aggressive biological behaviour, is proposed to reflect a possible progenitor cell origin or tumour dedifferentiation towardsa primitive phenotype. This work addresses that problem by studying CKs 7 and 19expression in N-diethylnitrosamine (DEN)-induced mouse HCCs. ICR mice weredivided into six DEN-exposed and six matched control groups. Samples were takenfrom each group at consecutive time points. Hyperplastic foci (13 lesions) occurredat 29-40 weeks (groups 8, 10 and 12) with diffuse dysplastic areas (19 lesions) andwith one hepatocellular adenoma (HCA) (at 29 weeks). HCCs (4 lesions) wereobserved 40 weeks after the first DEN administration (group 12). CKs 7 and 19showed identical expression patterns and located to large, mature hepatocytes, isolated or in small clusters. Hyperplastic foci and the single HCA were consistentlynegative for both markers, while dysplastic areas and HCCs were positive. Theseresults support the hypothesis that CKs 7 and 19 expression in hepatocellular malignancies results from a dedifferentiation process rather than from a possible progenitor cell origin

Systematic Review and Correlations with HPV Status and Patient Survival

Funding: This study was financially supported by the Virology Laboratory from the Pathology Department of the Portuguese Oncology Institute of Lisboa IUIC/1168, with contributions by the Research Center of the Portuguese Oncology Institute of Porto (project no. PI86-CI-IPOP-66-2017), by Base Funding-UIDB/00511/2020 of the Laboratory for Process Engineering, Environment, Biotechnology, and Energy—LEPABE—funded by national funds through the FCT/MCTES (PIDDAC), and Project 2SMART-engineered Smart materials for Smart citizens, with reference NORTE-01- 0145-FEDER-000054, supported by Norte Portugal Regional Operational Programme (NORTE 2020) under the PORTUGAL 2020 Partnership Agreement through the European Regional Development Fund (ERDF).PIK3CA mutations are believed to contribute to the pathogenesis of human papillomavirus (HPV)-associated head and neck squamous cell carcinomas (HNSCC). This study aims to establish the frequency of PIK3CA mutations in a Portuguese HNSCC cohort and to determine their association with the HPV status and patient survival. A meta-analysis of scientific literature also revealed widely different mutation rates in cohorts from different world regions and a trend towards improved prognosis among patients with PIK3CA mutations. DNA samples were available from 95 patients diagnosed with HNSCC at the Portuguese Institute of Oncology in Lisbon between 2010 and 2019. HPV status was established based on viral DNA detected using real-time PCR. The evaluation of PIK3CA gene mutations was performed by real-time PCR for four mutations (H1047L; E542K, E545K, and E545D). Thirty-seven cases were found to harbour PIK3CA mutations (39%), with the E545D mutation (73%) more frequently detected. There were no significant associations between the mutational status and HPV status (74% WT and 68% MUT were HPV (+); p = 0.489) or overall survival (OS) (3-year OS: WT 54% and MUT 65%; p = 0.090). HPV status was the only factor significantly associated with both OS and disease-free survival (DFS), with HPV (+) patients having consistently better outcomes (3-year OS: HPV (+) 65% and HPV (-) 36%; p = 0.007; DFS HPV (+) 83% and HPV (-) 43%; p = 0.001). There was a statistically significant interaction effect between HPV status and PIK3CA mutation regarding DFS (Interaction test: p = 0.026). In HPV (+) patients, PIK3CA wild-type is associated with a significant 4.64 times increase in the hazard of recurrence or death (HR = 4.64; 95% CI 1.02-20.99; p = 0.047). Overall, PIK3CA gene mutations are present in a large number of patients and may help define patient subsets who can benefit from therapies targeting the PI3K pathway. The systematic assessment of PIK3CA gene mutations in HNSCC patients will require further methodological standardisation.publishersversionpublishe

Sublineage A1 Drives Multi-Organ Carcinogenesis

by Fundação para a Ciência e Tecnologia/Ministério da Ciência, Tecnologia e Ensino Superior (FCT/MCTES, Portugal) through national funds to iNOVA4Health (UIDB/04462/2020 and UIDP/ 04462/2020); from the GenomePT project (POCI-01-0145-FEDER-022184), supported by COMPETE 2020—Operational Programme for Competitiveness and Internationalisation (POCI), Lisboa Portugal Regional Operational Programme (Lisboa2020), Algarve Portugal Regional Operational Pro- Int. J. Mol. Sci. 2022, 23, 12371 8 of 10 gramme (CRESC Algarve2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF), and by Fundação para a Ciência e a Tecnologia (FCT). This work was also supported by Fundos FEDER through the Programa Operacional Factores de Competitividade—COMPETE and by Fundos Nacionais through the Fundação para a Ciência e a Tecnologia within the scope of the project UID/BIM/00009/2019 (Centre for Toxicogenomics and Human Health-ToxOmics); and from LA/P/0045/2020 (ALiCE), UIDB/00511/2020 and UIDP/00511/2020 (LEPABE), funded by national funds through FCT/MCTES (PIDDAC); 2SMART (NORTE-01-0145- FEDER-000054), supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF).The study of human papillomavirus (HPV)-induced carcinogenesis uses multiple in vivo mouse models, one of which relies on the cytokeratin 14 gene promoter to drive the expression of all HPV early oncogenes. This study aimed to determine the HPV16 variant and sublineage present in the K14HPV16 mouse model. This information can be considered of great importance to further enhance this K14HPV16 model as an essential research tool and optimize its use for basic and translational studies. Our study evaluated HPV DNA from 17 samples isolated from 4 animals, both wild-type (n = 2) and HPV16-transgenic mice (n = 2). Total DNA was extracted from tissues and the detection of HPV16 was performed using a qPCR multiplex. HPV16-positive samples were subsequently whole-genome sequenced by next-generation sequencing techniques. The phylogenetic positioning clearly shows K14HPV16 samples clustering together in the sub-lineage A1 (NC001526.4). A comparative genome analysis of K14HPV16 samples revealed three mutations to the human papillomaviruses type 16 sublineage A1 representative strain. Knowledge of the HPV 16 variant is fundamental, and these findings will allow the rational use of this animal model to explore the role of the A1 sublineage in HPV-driven cancer.publishersversionpublishe

Inhalation of bacterial cellulose nanofibrils triggers an inflammatory response and changes lung tissue morphology of mice

In view of the growing industrial use of Bacterial cellulose (BC), and taking into account that it might become airborne and be inhaled after industrial processing, assessing its potential pulmonary toxic effects assumes high relevance. In this work, the murine model was used to assess the effects of exposure to respirable BC nanofibrils (nBC), obtained by disintegration of BC produced by Komagataeibacter hansenii. Murine bone marrow-derived macrophages (BMM) were treated with different doses of nBC (0.02 and 0.2 mg/mL, respectively 1 and 10 g of fibrils) in absence or presence of 0.2% Carboxymethyl Cellulose (nBCMC). Furthermore, mice were instilled intratracheally with nBC or nBCMC at different concentrations and at different time-points and analyzed up to 6 months after treatments. Microcrystaline Avicel-plus® CM 2159, a plant-derived cellulose, was used for comparison. Markers of cellular damage (lactate dehydrogenase release and total protein) and oxidative stress (hydrogen peroxidase, reduced glutathione, lipid peroxidation and glutathione peroxidase activity) as well presence of inflammatory cells were evaluated in brochoalveolar lavage (BAL) fluids. Histological analysis of lungs, heart and liver tissues was also performed. BAL analysis showed that exposure to nBCMC or CMC did not induce major alterations in the assessed markers of cell damage, oxidative stress or inflammatory cell numbers in BAL fluid over time, even following cumulative treatments. Avicel-plus® CM 2159 significantly increased LDH release, detected 3 months after 4 weekly administrations. However, histological results revealed a chronic inflammatory response and tissue alterations, being hypertrophy of pulmonary arteries (observed 3 months after nBCMC treatment) of particular concern. These histological alterations remained after 6 months in animals treated with nBC, possibly due to foreign body reaction and the organisms inability to remove the fibers. Overall, despite being a safe and biocompatible biomaterial, BC-derived nanofibrils inhalation may lead to lung pathology and pose significant health risks.The authors acknowledge Embrapa Tropical Agroindustry and Coordination for the Improvement of Higher Education Personnel (CAPES) and the project under the bilateral program FCT/CAPES: Bacterial Cellulose: a platform for the development of bionanoproducts for funding this research. This work was also financially supported by: European Investment Funds by FEDER/COMPETE/POCI - Operational Competitiveness and Internationalization Program, under Project POCI-01-0145-FEDER-006958, National Funds by FCT - Portuguese Foundation for Science and Technology, Project POCI-01-0145-FEDER-006939 (Laboratory for Process Engineering, Environment, Biotechnology and Energy - LEPABE funded by FEDER, funds through COMPETE2020 - Programa Operacional Competitividade e Internacionalização (POCI) - and by national funds through FCT. Rui Gil da Costa is supported by grant nº SFRH/BPD/85462/2012 from FCT, financed by the Portuguese Government and the Social European Fund. This study was supported by the Portuguese Foundation for Science and Technology (FCT) also under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684) and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte.info:eu-repo/semantics/publishedVersio