GATA-3 expression and its correlation with prognostic factors and survival in canine mammary tumors

Introduction

The transcription factor GATA-3 plays a significant role in mammary gland development and differentiation. Recent studies on human oncology have demonstrated its association with favorable pathologic factors in breast cancer. Canine mammary tumours, proposed as comparative and translational study models, have epidemiological, clinical, biological, and genetic characteristics similar to those of human breast cancers.

Methods

Here, we evaluated the frequency of GATA-3 expression in mammary tumors of dogs and its relationship with prognostic factors and survival. Tumor samples were obtained from 40 female dogs and grouped according to histological type into benign tumors (n = 10), carcinoma in mixed tumors (CMTs) (n = 20), and aggressive tumors (n = 10). CMTs were further separated according to histological grade, and data on clinical staging and diagnosis, histopathological grading, and survival rate were collected.

Results

GATA-3 and estrogen receptor (ER) expression were higher in benign and well-differentiated carcinomas than in aggressive tumors, which showed greater Ki-67 expression. The expression rate of ER in the studied groups was equivalent to that of GATA-3. We identified a strong positive correlation between GATA-3 and ER expression frequencies and a negative correlation between those of GATA-3 and Ki-67. There were associations between GATA-3 (p < 0.001), Ki-67 (p = 0.003), tumor size (p < 0.001), clinical stage (p = 0.002), lymph node metastasis (p < 0.001), and histological grade (p < 0.001) by univariate survival analysis. The parameters ER (p = 0.015) and GATA-3 (p = 0.005) also influenced survival in a multifactorial manner.

Discussion

Kaplan-Meier analysis of survival curves validated our previous findings that dogs with GATA-3 expression in ≥79.4% of cells had significantly higher survival rates (p < 0.001). The performance analysis showed that the expression of GATA-3 in ≥79.4% of cells effectively predicted survival or death in dogs with mammary tumors. Collectively, these results suggest that GATA-3 can be a relevant marker in the study of mammary tumor progression and has potential as a prognosis marker for predicting outcomes in canine mammary tumors.

Biofilm formation in vitro by Leptospira interrogans strains isolated from naturally infected dogs and their role in antimicrobial resistance

Leptospira interrogans is a biofilm-forming pathogen, however, there are few data involving Brazilian strains isolated from dogs and their antimicrobial sensitivity in planktonic and biofilm forms. The potential for biofilm formation and antimicrobial resistance in naturally infected dogs is a fundamental approach towards disease epidemiology and the establishment of consistent prophylaxis and control measures. The objective of this study was to evaluate in vitro biofilm formation of a reference strain (L. interrogans, sv. Copenhageni L1 130 - L20) and of L. interrogans isolated from dogs (C20, C29, C51, C82), with subsequent evaluation of antimicrobial susceptibility in planktonic and biofilm forms. The semi quantification of biofilm production revealed a dynamic process of development over time, with mature biofilm formation early on the seventh day of incubation. All strains were efficient for in vitro biofilm formation and, in this form, they were considerably more resistant compared to their planktonic form, with MIC₉₀ of 1600 μg/mL for amoxicillin, 800 μg/mL for ampicillin, and >1600 μg/mL for doxycycline and ciprofloxacin. The strains studies were isolated on naturally infected dogs that might act as reservoirs and sentinels for human infections. The potential to antimicrobial resistance together with the close relation between dogs and humans indicates the need for greater actions on disease control and surveillance. Moreover, biofilm formation may contribute to the persistence of Leptospira interrogans in the host and these animals can act as chronic carriers, disseminating the agent in the environment.

Factors related to the suppression of the antitumour immune response in female dogs with inflammatory mammary carcinoma

Inflammatory mammary carcinoma (IMC), a neoplasia affecting women and female dogs, is considered an aggressive cancer with high metastatic potential and a low survival rate. Studies focused on the tumour microenvironment indicate that the aggressive behaviour of this tumour is primarily correlated with immunological factors as well as inflammation. The objective of this study was to analyse the possible strategies used by the tumour cells to suppress the immune response in female dogs with IMC. Forty-six female dogs were divided into three groups: control (C, n = 10), IMC (n = 14) and mammary carcinoma (MC, n = 22). Clinical-pathological evaluations, survival at follow-up, immunophenotyping of leukocytes in peripheral blood and tumours, and immunohistochemical evaluation of CD4⁺, granzyme B, perforin and FAS-L were performed. Clinical and pathological results showed a higher frequency of the primary form of neoplasia, solid arrays of tumor cells and a lower survival rate in the IMC group (30 days). Morphometric analysis of inflammatory infiltrate revealed more lymphocytes and macrophages in the IMC group. Immunophenotyping analysis of peripheral blood revealed a higher frequency of CD8⁺ T-cells (p = 0.0017), a lower frequency of CD4⁺ T-cells (p <0.0001), and significantly higher mean MHCI and MHCII CD14⁺ fluorescence intensity in the IMC group (p = 0.038 and p = 0.0117, respectively). The immunohistochemical evaluation of tumour sections showed fewer FAS-L-positive inflammatory cells in the IMC group. These results suggest the important contribution of CD8⁺ T-cells, macrophages and FAS-L in the aggressiveness of IMC.

Expression of VCAN and its receptors in canine mammary carcinomas with or without myoepithelial proliferation

The proteoglycan versican (VCAN) plays a complex role in cancer. The expression of this molecule has been related to invasion and progression in malignant mixed tumors, such as carcinoma in mixed tumors (CMT) of the canine mammary gland. In addition, its interaction with surface cell receptors EGFR, HER-2 and CD44 in malignant epithelial cells may be responsible for proliferation and cellular motility in early stages of cancer. We comparatively evaluated the expression of this proteoglycan and its receptors in in situ and invasive areas of simple carcinomas (SC) and CMT to investigate similarities and differences between these histological types. Immunohistochemistry was performed with anti-VCAN, anti-CD44, anti-EGFR and anti-HER-2 antibodies in 32 cases of SC or CMT. VCAN was highly expressed in stroma adjacent to invasive areas in SC and CMT. CMTs presented comparatively higher expression of VCAN in stroma adjacent to in situ and in invasive areas than in corresponding areas in SCs. In CMT, EGFR and HER-2 expressions were higher in situ compared to invasive areas. In contrast, increased CD44 and EGFR expression was found in invasive areas in SC compared to CMT. These results indicate that versican expression is similarly associated with invasiveness in SC and CMT, however higher levels were seen in CMT suggesting that the presence of myoepithelial proliferation in this tumor type participates in stromal composition and promoting an increase in the expression of versican.

Hyperresistinemia in Obese Female Dogs With Mammary Carcinoma in Benign-Mixed Tumors and Its Correlation With Tumor Aggressiveness and Survival

Resistin is associated with metabolic, inflammatory, and neoplastic disorders, and is also considered a prognostic marker in human oncology. Canine mammary tumors have epidemiological, clinical, biological, and genetic characteristics similar to those of women and are proposed as a comparative study model. Here, we evaluate the serum levels of resistin in female dogs with or without mammary carcinoma in mixed tumors (CBMT) and its correlation with the proliferative potential of the tumor, obesity, and survival. Eighty dogs grouped according to the presence (50) or absence (30) of CBMT, reproductive status and body condition were assessed for weight, fat percentage, and canine body mass index. The characteristic of the proliferative potential of the tumor (Ki-67) was evaluated. Ki-67 levels (p = 0.024), staging (p = 0.004), and grade (p = 0.016) influenced the survival of the female dogs. Through a multifactorial analysis, it could be seen that the parameters proliferation index (Ki-67) (p = 0.044) and staging (p = 0.036) influenced the survival of the animals. Neutered and overweight dogs from the control and CBMT groups showed hyperresistinemia. Ki-67 expression and resistin levels in dogs with CBMT were higher in overweight dogs than in dogs with normal weight (p = 0.0001). The survival rate of dogs with CBMT, obese and with high levels of resistin (8,400 μg L⁻¹) was lower when compared to those with lower levels of resistin. These results showed an important relationship between hyperresistinemia, tumor proliferative potential and excessive body fat, suggesting that resistin levels may act as an interesting prognostic marker in patients with CBMT.

Erratum to "Mixed tumors of the canine mammary glands: Evaluation of prognostic factors, treatment, and overall survival" [7C (June 2019) 100039]

[This corrects the article DOI: 10.1016/j.vas.2018.09.003.].

Versican and Tumor-Associated Macrophages Promotes Tumor Progression and Metastasis in Canine and Murine Models of Breast Carcinoma

Versican and tumor-associated macrophages (TAMs) are involved in growth and metastases in several cancers. Here, we investigated the potential role of versican, a matrix proteoglycan, and its correlation with TAMs infiltrates in different stages of two different breast cancer models: spontaneous canine mammary gland carcinomas and the murine 4T1 breast cancer model. The stromal versican expression was correlated with TAMs accumulation in tumors with an advanced stage from spontaneous canine mammary carcinoma samples. Versican expression in mice, identified in late stages of tumor progression, was associated to a high number of peri-tumoral infiltrating TAMs. Indeed, TAMs were related to a pro-inflammatory and pro-angiogenic state in the primary tumor. Furthermore, TAMs accumulation was related to versican expression in the lungs and an increased number of pulmonary metastatic nodules with pulmonary mechanical dysfunction, which was due to leukocyte influx in the airways and elevated growth factor levels in the microenvironment. Thus, we suggest that versican and TAMs as attractive targets for breast cancer therapy.

Mixed tumors of the canine mammary glands: Evaluation of prognostic factors, treatment, and overall survival

Mixed tumors are the most frequent mammary gland neoplasms in bitches; however, studies that thoroughly describe their clinicopathological data, treatment approaches, and the survival of bitches with mixed tumors are scarce. This study evaluated the epidemiological and clinicopathological data, prognostic factors, and therapeutic approaches for bitches with mixed tumors. In all, 162 benign mixed tumors, 682 carcinomas in mixed tumors, and 60 carcinosarcomas were included. Regarding tumor size, T3 lesions were predominantly associated with carcinosarcomas, while T1 and T2 lesions occurred more frequently in benign mixed tumors and in carcinomas in mixed tumors. Based on clinical staging, most bitches with benign mixed tumors presented with stage I tumors; 92% of bitches with carcinomas in mixed tumors presented with stage I-III tumors, while 8% presented with stage IV-V tumors; and 70% of bitches with carcinosarcomas presented with stage I-III tumors, while 30% presented with stage IV-V tumors. Surgery was curative for bitches with benign mixed tumors and for those with stage I-III carcinomas in mixed tumors. Combination therapy in bitches with carcinomas in mixed tumors (IV-V) and carcinosarcomas resulted in a higher overall survival compared with bitches who underwent surgery only. Carcinosarcomas presented higher relapse rates and distant metastases than carcinomas in mixed tumors did.

The investigation of transcriptional repression mediated by ZEB2 in canine invasive micropapillary carcinoma in mammary gland

The E-cadherin loss has frequently been associated with transcriptional repression mediated by transcription factors, such as the Zinc Finger E-Box Binding Homeobox-2 (ZEB2). Invasive micropapillary carcinomas (IMPCs) of the breast are aggressive neoplasms frequently related to lymph node metastasis and poor overall survival. In the canine mammary gland, IMPCs has just been reported and, based on its behavioral similarity with the human IMPCs, appears to be a good spontaneous model to this human entity. This study aimed to evaluate the relationship between E-cadherin and ZEB2 in a spontaneous canine model of invasive micropapillary carcinoma of the mammary gland. The correlation among gene expression (ZEB2 and CDH1) and clinicopathological findings was also explored. Nineteen cases of IMPC of the canine mammary gland were obtained, protein and mRNA expression were investigated through immunohistochemistry and RNA In Situ Hybridization, respectively. To better understand the relationship between E-cadherin and ZEB2, immunofluorescence was performed in canine IMPCs. Immunohistochemically, most of IMPCs showed 1+ (14/19, 73.7%) for E-cadherin; and positivity for ZEB2 was diagnosed in 47.4% of the IMPCs. Regarding the RNA In Situ Hybridization (ISH), most of IMPCs showed 4+ and 0+ for E-cadherin (CDH1) and ZEB2 respectively. Through immunofluorescence, the first and second more frequent combinatorial group were E-cadherin⁺ZEB2^- and E-cadherin⁺ZEB2⁺; neoplastic cells showing concomitantly weak expression for E-cadherin and positivity for ZEB2 were frequently observed. A negative correlation was observed between E-cadherin and progesterone receptor expression in IMPCs. Based on these results, canine mammary IMPCs show E-cadherin lost and, at times reveals nuclear positivity for the transcription factor ZEB2 that seems to exert transcriptional repression of the CDH1.

Consensus for the diagnosis, prognosis and treatment of feline mammary tumors

Mammary neoplasms are described as the third most common type of feline tumor, after haematopoietic and skin tumors, and present a challenge for clinicians because the prognosis for feline mammary tumors ranges from guarded to poor. Thus, it is necessary to define new therapeutic approaches and establish more in-depth knowledge about this disease in felines. The main aspects of the diagnosis, prognosis and treatment of feline mammary neoplasia were discussed, aiming to standardize the criteria and to serve as a guide for pathologists and veterinary clinicians.

Expression of epidermal growth factor receptor (EGFR) in cholangiocarcinomas: predictive factors and survival

OBJECTIVE

to evaluate the expression of the epithelial growth factor receptor (EGFR) by immunohistochemistry, and to verify its association with prognostic factors and survival of patients operated by cholangiocarcinoma.

METHODS

we verified the immunohistochemical expression of EGFR in 35 surgical specimens of cholangiocarcinoma (CCA). We obtained survival curves with the Kaplan-Meier method.

RESULTS

we found significant EGFR expression in ten (28.6%) of the 35 CCAs, eight with score 3 and two with score 2. Advanced stages (III and IV) presented higher EGFR expression (p=0.07). The clinical characteristics that were most associated with positive EGFR expression were female gender (p=0.06) and absence of comorbidities (p=0.06). Overall survival at 12, 24, 36 and 48 months was 100%, 82.5%, 59% and 44.2%, respectively. The survival of EGFR positive patients at 12, 24, 36 and 48 months was 100%, 75%, 50% and 0%, whereas for negative EGFR patients it was 100%, 87.5%, 65.6% and 65.6%, respectively.

CONCLUSION

EGFR expression occurred in 28.6% of the cases studied and was associated with lower survival.

HER-2 and EGFR mRNA Expression and Its Relationship with Versican in Malignant Matrix-Producing Tumors of the Canine Mammary Gland

Versican expression promotes tumor growth by destabilizing focal cell contacts, thus impeding cell adhesion and facilitating cell migration. It not only presents or recruits molecules to the cell surface, but also modulates gene expression levels and coordinates complex signal pathways. Previously, we suggested that the interaction between versican and human epidermal growth factor receptors may be directly associated with tumor aggressiveness. Thus, the expression of EGFR and HER-2 in these neoplasms may contribute to a better understanding of the progression mechanisms in malignant mammary tumors. The purpose of this study was to correlate the gene and protein expressions of EGFR and HER2 by RNA In Situ Hybridization (ISH) and immunohistochemistry (IHC), respectively, and their relationship with the versican expression in carcinomas in mixed tumors and carcinosarcomas of the canine mammary gland. The results revealed that EGFR mRNA expression showed a significant difference between in situ and invasive carcinomatous areas in low and high versican expression groups. Identical results were observed in HER-2 mRNA expression. In immunohistochemistry analysis, neoplasms with low versican expression showed greater EGFR immunostaining in the in situ areas than in invasive areas, even as the group presenting high versican expression displayed greater EGFR and HER-2 staining in in situ areas. Significant EGFR and HER-2 mRNA and protein expressions in in situ carcinomatous sites relative to invasive areas suggest that these molecules play a role during the early stages of tumor progression.

Relationship between the expression of versican and EGFR, HER-2, HER-3 and CD44 in matrix-producing tumours in the canine mammary gland

Versican is an extracellular matrix proteoglycan that has been identified as a modulator of adhesion loss, cell motility, and tumour progression. This motility results from the interaction between versican and cell surface receptors. Studies have also demonstrated the relationship between this molecule and invasion in canine mammary tumours. Given the evidence for the participation of proteoglycans in tumour progression, this study aimed to assess versican expression and its association with cell surface receptors; human epidermal growth factor receptors 1, 2, and 3 (EGFR, HER-2, and HER-3) and CD44 through an immunohistochemical analysis of benign mixed tumours (BMTs), carcinomas in mixed tumours (CMTs), and carcinosarcomas (CSs) of the canine mammary gland. Malignant tumours were divided into low and high groups with respect to versican stromal expression. The results indicated that the BMTs showed weak stromal versican expression and correlations between the expression of stromal versican and EGFR in the epithelial membrane in benign areas (p=0.013, r=0.571). A higher stromal versican expression was observed adjacent to invasive epithelial areas compared with in situ areas in CMTs and CSs, suggesting a direct relationship between versican expression and invasiveness. Furthermore, the CSs exhibited a higher expression of HER-2, cytoplasmic HER-3, and CD44 in epithelial invasive cells in cases of higher stromal versican expression. Therefore, the cell surface receptors (HER-2, HER-3, and CD44) are more evident in CSs that overexpress versican in stroma adjacent to the invasive areas. These findings suggest that the association between these molecules may be directly related to the biological behaviour and invasiveness of these canine mammary tumours.

Cytologic analysis of the mammary papillar discharge in a canine micropapillary carcinoma

This is a report on the cytologic analysis of the mammary papillar discharge in a 7-year-old female Doberman dog with an invasive micropapillary carcinoma. Cytologic evaluation of nipple discharge is a well-known method for the rapid diagnosis of breast cancer in women. However, there is no previous report regarding the use of this technique for assessing mammary tumors in dogs. The aim of this study was to describe the use of mammary papillar discharge cytology for diagnosing a micropapillary carcinoma in a dog. Cytologically, evaluation of the papillar discharge revealed cells arranged in clusters in a papillary pattern or in a morula-like arrangement, suggesting the diagnosis of a micropapillary carcinoma, which was subsequently confirmed by histopathology. Thus, mammary papillar discharge cytology should be considered as an ancillary method for evaluating mammary diseases in dogs.