Background and Aim: Mast cell tumors (MCTs) are malignant neoplasms that are common in dogs. Their biological behavior is variable and unpredictable. The aim of the present study was to analyze the histological classification and expression of markers of canine MCTs. Materials and Methods: Thirty samples of canine MCTs were graded according to the histological classification methods of Patnaik and those of Kiupel. The expression of phosphoprotein 53 (p53) and c-kit proteins was quantified by immunohistochemistry using image processing software, ImageJ - a public domain computer program, developed at the National Institutes of Health. Results: It was possible to determine the grade of 100% of the samples. According to Patnaik's classification, 20.00% of the samples were Grade 1, 43.30% were Grade 2, and 36.70% were Grade 3. According to Kiupel's classification, 56.67% of the samples were of high intensity and 43.33% were of low intensity. Grade 1 tumors had the highest expression of p53 and c-kit, and Grade 2 had the lowest expression. The results showed that it is necessary to perform both histological grading methods. The classification into high and low intensity may provide more consistent results than the three-level grading system. However, a smaller number of categories, although it facilitates the classification, may not be sufficient for the prognosis. Conclusion: Quantitative evaluation of p-53 and c-kit expression is a useful tool to increase the accuracy of the analysis and to aid in choosing the treatment method for canine MCTs. Histological grading should be combined with other diagnostic methods.

The dairy industry diversifies products with organoleptic, dietary, functional, and nutritional properties according to consumer demands and welfare. This study aimed to examine the profile of consumers, data on milk consumption, knowledge, and familiarity with A2A2 milk in the Tocantins State, Brazil. A qualitative survey was carried out through a questionnaire applied to 389 people, distributed in 34 municipalities. Regarding the consumption of dairy products, 21.31% of participants described having some type of discomfort when consuming them. Among participants, 46.27% consumed one to two liters, 28.28% two to four liters, and 25.45% more than four liters per week. Milk was the main dairy product consumed, according to 59.13% of participants. Of all respondents, 76.10% pay little or no attention to the information on the label, versus 23.90% who did not. Regarding A2A2 milk, 40.36% possessed some knowledge about it, while 59.64% did not. 42.93% and 30.59% of participants stated they would be willing to pay over 10% or 50% more, respectively, whereas 24.94% would not pay any additional amount on the price of A2A2 milk. Willingness to pay a low additional amount was related to consumers who heard of, but knew little about this product, whereas the likelihood of paying higher additional amounts was associated with respondents who heard and know about the product.

Background and Aim: New substances for neoplasm treatment have to be carefully studied to minimize adverse effects and prevent disease progression stimulation. Jatobá is a typical tree of the Cerrado and Caatinga biome, with antifungal, antimicrobial, larvicide, antioxidant, and antiproliferative properties. This study aimed to investigate the action of the crude extract of Jatobá leaves (EBFJ) on canine osteosarcoma (CO) cells and analyze the expression of biomarkers in neoplasm progression. Materials and Methods: D17 cells were cultured and subjected to treatment with EBFJ at different concentrations (10 μg/ mL; 100 μg/mL; 1000 μg/mL; 2000 μg/mL; and 5000 μg/mL) and exposure times (24 h, 48 h, and 72 h). The tetrazolium reduction assay and the immunocytochemistry technique, with anti-Bcl2, anti-p53, and anti-Ki-67 antibodies, were used to observe the effect of the extract on cell proliferation. Results: Doses of 2000 μg and 5000 μg had cell viability of 300.80% and 361.84%, respectively. The extract did not show significant cytotoxicity of samples with the control group. The confluence of cells, the number of labeled cells, and the expression of Bcl2, Ki-67, and p53 were higher in the groups treated with EBFJ, with a statistical difference from the group without treatment. Conclusion: EBFJ was not cytotoxic and had a proliferative effect on CO D17 cells. The confluence of cells, the number of labeled cells, and the expression of Bcl2, Ki-67, and p53 were higher in the groups treated with the extract.

Canine osteosarcoma is the most common bone tumor in dogs. It has an intense metastatic capacity, and the patient survival rate is low in this disease. Curcumin, the most important compound derived from the plant Curcuma longa L., has been widely studied and has shown considerable antineoplastic effects against many tumors. This study aims to identify the activation of specific proteins of apoptosis pathways, tumor survival, and poor prognosis of this disease in D-17 osteosarcoma cells. For this, the cells were cultured and treated with curcumin at concentrations of 20μM, 50 μM, and 100 μM in prepared and fixed slides. Subsequently, we performed the immunocytochemical analysis with anti-caspase3, anti-JNK, anti-AMPK, anti-p53, anti-AKT, and anti-mTOR antibodies. Curcumin activated the cell-death proteins caspase-3, JNK, and AMPK, reduced the expression of the mutated p53 protein, and did not alter the AKT and mTOR proteins in canine osteosarcoma cells in vitro. Thus, curcumin induces extrinsic apoptosis mediated by caspase, JNK, and cAMP/AMPK in canine osteosarcoma cells. Besides, it has the potential to improve the tumor prognosis of this disease by inactivating the mutated p53. However, it does not interfere with AKT/mTOR expression, related to tumor proliferation and survival. Such results will serve as a basis for future studies that analyze the effect of curcumin in vivo on this disease.

The Cerrado biome is a source of chemical molecules with great medicinal potential. The substances extracted from pequi, the fruit of Caryocar brasiliense, have antiparasitic, antioxidant, and antineoplastic properties. Canine osteosarcoma is a highly aggressive and metastatic bone tumor, not very responsive to current chemotherapy modalities. This study aimed to show the effects of the ethanol extract of pequi peel (EEPP) on canine osteosarcoma cells, in addition to suggesting a metabolic route that explains the action of the extract. D-17 cells were seeded and exposed to EEPP at concentrations of 0, 10, and 100 µg/mL. After treatment, the cell nuclei were marked with DAPI and quantified using fluorescence microscopy. The expression of proteins p53, Ki-67, Bcl-2, Akt, AMPK, and mTOR was analyzed using immunocytochemistry. By using DAPI, we found a reduction in the number of quantified nuclei, time, and dose-dependent. The labeling of p53, Ki-67, and Bcl-2, antibodies decreased in groups exposed to EEPP. The opposite was observed with Akt, AMPK, and mTOR antibodies, where the protein was not found in the control group but was expressed in groups exposed to EEPP. We suggest a possible metabolic route where EEPP promotes cell death and cell cycle control in D-17 cells.

The development of new chemotherapy drugs is a premise for the scientific community in recent years, mainly through the use of plants and other natural sources. In this context, analyses of cytotoxicity and residual effect have become essential for the establishment of new therapies. Therefore, this study aims to evaluate the cytotoxic and residual effects of ethanol extract of pequi peel (EEPP) on canine osteosarcoma cells. For this, we used analyses of cell viability, cytotoxicity, IC₅₀, and cell survival after therapy in treatments of 24, 48, and 72 hours. We used the design of the randomized block, using an Analysis of Variance with Tukey’s posthoc test to compare the treatments, considering a 5% significance. The extract showed no cytotoxic effect within 24 hours of treatment, but a protective effect, or possibly a mitotic-inducing effect on osteosarcoma cells. However, at 48 and 72 hours, we found gradual cytotoxicity favoring the effective control of neoplastic cells, obtaining, on average, 55% of cytotoxicities at concentrations of 10 to 100 µg/mL. IC₅₀ values were 4.05 µg/mL for the 48-hour group and 4.53 µg/mL for the 72-hour group. The treatment residual effect reduced cell growth after the exposure to the extract. The survival factor was lower (18.81%) in the 72-hour group, with a concentration of 10 µg/mL and higher (81.33%) in the 48-hour group, with a concentration of 100 µg/mL. These results suggest that the ethanol extract of pequi peel promotes the increase in cell viability within 24 hours, cytotoxic action in exposures over 48 hours, and time-dependent residual effect on canine osteosarcoma cells.