Cytotoxic effects of crotoxin from Crotalus durissus terrificus snake in canine mammary tumor cell lines

Background

Mammary gland tumors are the most prevalent neoplasm in intact female dogs, and they are good natural models to study comparative oncology. Most canine mammary malignancies, as in women, are commonly refractory to conventional therapies and demand continuous new therapeutic approaches. Crotalus durissus terrificus, also called rattlesnake, has more than 60 different proteins in its venom with multiple pharmaceutical uses, such as antitumor, antiviral, and antimicrobial action. Crotoxin, a potent β-neurotoxin formed by the junction of two subunits, a basic subunit (CB-PLA2) and an acidic subunit (crotapotin), has already been reported to have anticancer properties in different types of cancers.

Methods

In this work, we describe the cytotoxic potential of crotoxin and its subunits compared to doxorubicin (drug of choice) in two canine mammary carcinoma cell lines.

Results

Crotoxin, CB-PLA2, crotalic venom, and doxorubicin decreased cell viability and the ability to migrate in a dose-dependent manner, and crotapotin did not present an antitumoral effect. For all compounds, the predominant cell death mechanism was apoptosis. In addition, crotoxin did not show toxicity in normal canine mammary gland cells.

Conclusion

Therefore, this work showed that crotoxin and CB-PLA2 had cytotoxic activity, migration inhibition, and pro-apoptotic potential in canine mammary gland carcinoma cell lines, making their possible use in cancer research.

In vitro evaluation of the efficacy of photodynamic therapy using 5-ALA on homologous feline mammary tumors in 2D and 3D culture conditions and a mouse subcutaneous model with 3D cultured cells

BACKGROUND

Numerous studies have shown that photodynamic therapy (PDT) has a therapeutic effect on mammary tumor cells, with 5-aminolevulinic acid (5-ALA-HCL) being a commonly used photosensitizer for PDT. Feline mammary tumors (FMTs) are relatively common. However, the cytotoxic and antitumor effects of 5-ALA-PDT on FMTs have not been clarified. To this end, we evaluated the therapeutic effect of 5-ALA-PDT on FMTs through in vitro experiments using an FMT FKR cell line established for this study.

METHODS

We performed 5-ALA-PDT in 2D-cultured FKR-A (adherent cells) and 3D-cultured FKR-S (spheroid cells) cells and performed a series of studies to evaluate the cell viability and determine the protoporphyrin IX (PpIX) content in the cells as well as the expression levels of mRNAs associated with PpIX production and release. An in vivo study was performed to assess the effectiveness of 5-ALA-PDT.

RESULTS

There was a significant difference in the concentration of PpIX in FMT cells under different incubation culture modes (2D versus 3D culture). The concentration of PpIX in FMT cells was correlated with the differences in cell culture (2D and 3D) as well as the expression levels of genes such as PEPT1, PEPT2, FECH, and HO-1.

CONCLUSIONS

In the in vitro study, 5-ALA-PDT had a stronger inhibitory effect on 3D-cultured FKR-S cells, which resemble the internal environment of organisms more closely. We also observed a significant inhibitory effect of 5-ALA-PDT on FMT cells in vivo. To our knowledge, this is the first study on 5-ALA-PDT for FMTs under both 2D and 3D conditions.

Integrative multi-omic sequencing reveals the MMTV-Myc mouse model mimics human breast cancer heterogeneity

BACKGROUND

Breast cancer is a complex and heterogeneous disease with distinct subtypes and molecular profiles corresponding to different clinical outcomes. Mouse models of breast cancer are widely used, but their relevance in capturing the heterogeneity of human disease is unclear. Previous studies have shown the heterogeneity at the gene expression level for the MMTV-Myc model, but have only speculated on the underlying genetics.

METHODS

Tumors from the microacinar, squamous, and EMT histological subtypes of the MMTV-Myc mouse model of breast cancer underwent whole genome sequencing. The genomic data obtained were then integrated with previously obtained matched sample gene expression data and extended to additional samples of each histological subtype, totaling 42 gene expression samples. High correlation was observed between genetic copy number events and resulting gene expression by both Spearman's rank correlation coefficient and the Kendall rank correlation coefficient. These same genetic events are conserved in humans and are indicative of poor overall survival by Kaplan-Meier analysis. A supervised machine learning algorithm trained on METABRIC gene expression data was used to predict the analogous human breast cancer intrinsic subtype from mouse gene expression data.

RESULTS

Herein, we examine three common histological subtypes of the MMTV-Myc model through whole genome sequencing and have integrated these results with gene expression data. Significantly, key genomic alterations driving cell signaling pathways were well conserved within histological subtypes. Genomic changes included frequent, co-occurring mutations in KIT and RARA in the microacinar histological subtype as well as SCRIB mutations in the EMT subtype. EMT tumors additionally displayed strong KRAS activation signatures downstream of genetic activating events primarily ascribed to KRAS activating mutations, but also FGFR2 amplification. Analogous genetic events in human breast cancer showed stark decreases in overall survival. In further analyzing transcriptional heterogeneity of the MMTV-Myc model, we report a supervised machine learning model that classifies MMTV-Myc histological subtypes and other mouse models as being representative of different human intrinsic breast cancer subtypes.

CONCLUSIONS

We conclude the well-established MMTV-Myc mouse model presents further opportunities for investigation of human breast cancer heterogeneity.

The landscape of PBMC methylome in canine mammary tumors reveals the epigenetic regulation of immune marker genes and its potential application in predicting tumor malignancy

BACKGROUND

Genome-wide dysregulation of CpG methylation accompanies tumor progression and characteristic states of cancer cells, prompting a rationale for biomarker development. Understanding how the archetypic epigenetic modification determines systemic contributions of immune cell types is the key to further clinical benefits.

RESULTS

In this study, we characterized the differential DNA methylome landscapes of peripheral blood mononuclear cells (PBMCs) from 76 canines using methylated CpG-binding domain sequencing (MBD-seq). Through gene set enrichment analysis, we discovered that genes involved in the growth and differentiation of T- and B-cells are highly methylated in tumor PBMCs. We also revealed the increased methylation at single CpG resolution and reversed expression in representative marker genes regulating immune cell proliferation (BACH2, SH2D1A, TXK, UHRF1). Furthermore, we utilized the PBMC methylome to effectively differentiate between benign and malignant tumors and the presence of mammary gland tumors through a machine-learning approach.

CONCLUSIONS

This research contributes to a better knowledge of the comprehensive epigenetic regulation of circulating immune cells responding to tumors and suggests a new framework for identifying benign and malignant cancers using genome-wide methylome.

Amounts of tissue magnesium and some trace elements in cats with mammary tumors related to various clinicopathological parameters

BACKGROUND

Mammary tumors are one of the major malignancies seen in cats. Researchers have indicated the similarity between the epidemiological and clinicopathological patterns of feline mammary tumors and human breast cancer (HBC). In recent years, the investigation of trace elements in cancer tissues becomes prevalent in HBC due to the role of these elements in biochemical and physiological processes. This study, it is aimed to evaluate some trace elements in feline mammary tumors according to clinical and pathological findings.

METHODS

A total of 60 tumoral masses from 16 female cats with mammary tumors were included in the study. The study groups were formed according to histopathology as malignant epithelial tumor (MET; n = 39) and hyperplasia and dysplasia (H&D; n = 21). Copper (Cu), Iron (Fe), Magnesium (Mg), Manganese (Mn), Selenium (Se) and Zinc (Zn) trace elements in mammary tissues were analyzed by using an inductively coupled plasma-optical emission spectrophotometer.

RESULTS

The mean age and weight of the cats were 11.75 ± 0.75 years and 3.35 ± 0.21 kg; respectively. Eleven of 16 cats were intact whereas the rest of them had been spayed. Metastases were observed in 10 cats. Tissue Mg level in group MET was significantly higher than in group H&D (P < 0.01) while the other elements had not significant differences between the groups. In group MET, analyzed elements were not statistically significant related to the inflammation, ulceration and invasion to the peripheral muscle (P > 0.05). However, tissue Fe level was significantly higher in T2 than in T3 (P < 0.05). The mean levels of tissue Fe, Mg and Mn had significant differences related to histological grading as P < 0.01, P < 0.05 and P < 0.001; respectively. A mild to severe correlation was found between tissue Zn and Se, Cu, Fe, Mg, and Mn levels.

CONCLUSION

Tissue Mg and some trace elements were evaluated in feline mammary tumours in regard to various clinicopathological parameters. Tissue Mg level was sufficient to differentiate the malignant epithelial tumors from hyperplasia and dysplasia. However, Mn and Se tended to distinguish different tumor types. Tissue Fe, Mg and Mn had significant differences related to histological grading. Also, the Fe level was significantly higher in T2 than in T3 and Zn level tended to be higher in T3 than in T1. It was concluded that Mg, Se, Mn, Fe, Cu and Zn provided useful information on the pathogenesis of feline mammary tumors. Further research is needed on the tissue and serum concentrations of trace elements which may provide valuable information for the disease prognosis.

Reduction of Staphylococcus epidermidis in the mammary tumor microbiota induces antitumor immunity and decreases breast cancer aggressiveness

The mammary gland hosts a microbiota, which differs between malignant versus normal tissue. We found that aerosolized antibiotics decrease murine mammary tumor growth and strongly limit lung metastasis. Oral absorbable antibiotics also reduced mammary tumors. In ampicillin-treated nodules, the immune microenvironment consisted of an M1 profile and improved T cell/macrophage infiltration. In these tumors, we noted an under-representation of microbial recognition and complement pathways, supported by TLR2/TLR7 protein and C3-fragment deposition reduction. By 16S rRNA gene profiling, we observed increased Staphylococcus levels in untreated tumors, among which we isolated Staphylococcus epidermidis, which had potent inflammatory activity and increased Tregs. Conversely, oral ampicillin lowered Staphylococcus epidermidis in mammary tumors and expanded bacteria promoting an M1 phenotype and reducing MDSCs and tumor growth. Ampicillin/paclitaxel combination improved the chemotherapeutic efficacy. Notably, an Amp-like signature, based on genes differentially expressed in murine tumors, identified breast cancer patients with better prognosis and high immune infiltration that correlated with a bacteria response signature. This study highlights the significant influence of mammary tumor microbiota on local immune status and the relevance of its treatment with antibiotics, in combination with breast cancer therapies.

Evidence for heterogeneity in response to treatment in mammary tumors of dogs as happens in humans

Tumors are formed by various clones developed over a long time. This gives rise to a heterogeneous nature. This heterogeneity is the hardest challenge in the treatment of cancers because it is the main reason for drug resistance. This is a well-known fact in human cancer. Therefore, we have reasoned that if the tumor heterogeneity in canine mammary gland tumors (CMGTs) could be shown by an ex vivo assay, which will be used first time in veterinary oncology practice, this could be used further in clinics. To achieve this, twenty-six patients were included in the study. Tumor tissues were obtained from animals during routine surgery. Tumor cells were isolated and seeded ex vivo. The cells were exposed to anticancer drugs that are clinically used. Seven days after the treatment, chemosensitivity has luminometrically been assayed by ATP-tumor chemosensitivity assay (ATP-TCA). It has clearly been shown that all the tumor tissues have responded to treatment differently, implying that heterogeneity exists in mammary tumors. There has also been found that there was a weak to moderate statistically significant correlation between tumor size and drug index. However, there has been no correlation between drug index and metastasis to lymph nodes. Hyperplasic areas had relatively higher PCNA values. The results of our study demonstrate the heterogeneity in responses to in vitro drugs. Clinical trials based on test results and follow-up studies with large numbers of animals are needed to prove that such chemotherapeutic activity assessment tests can be clinically useful in predicting drug responses in CMGTs.

Pathological Complete Response following Neoadjuvant Chemotherapy in Invasive Ductal Carcinoma with Mammary Paget's Disease: A Case Report

Mammary Paget's disease is a rare malignancy. Mastectomy or breast-conserving surgery has been considered as the standard treatment, while there have been few reports of neoadjuvant chemotherapy (NAC). A 53-year-old woman with erythema and skin ulceration of the left breast was admitted to our institution. Breast examinations revealed left invasive ductal carcinoma (cT1bN0M0, cStage I), and a punch biopsy of the left mammary erythema indicated Paget's disease (cTisN0M0, cStage0). The patient received NAC because of multiple lesions. Consequently, the breast tumor clinically disappeared, and the erythema improved. These outcomes made it easier to perform surgery (left mastectomy and sentinel node biopsy). Histopathological examination revealed no residual cancer cells in either the mammary gland or breast skin, and no metastasis was found in the sentinel lymph node. Therefore, NAC may be a useful treatment for mammary Paget's disease.

Co-exposure to BPA and DEHP enhances susceptibility of mammary tumors via up-regulating Esr1/HDAC6 pathway in female rats

Breast cancer (BrCa) as one of the major malignancies threatening women's health worldwide occurs due to the genetic and environmental interactions. Epidemiological studies have suggested that exposure to endocrine disrupting chemicals (EDCs) can elevate the risk of breast cancer. Di-(2-ethylhexyl)-phthalate (DEHP) and bisphenol A (BPA) are known as two typical EDCs. Although several studies have implied that there appear to have adverse effects of exposure to BPA or DEHP alone on breast development, no study to date has demonstrated the exact toxic effect of combined exposure to DEHP and BPA on breast tumorigenesis. In the present study, we performed an in vivo experiment including 160 female Sprague-Dawley (SD) rats, in which 80 rats were randomly allocated to 4 groups including control group given to normal diet, DEHP (150 mg/kg body weight/day), BPA (20 mg/kg body weight/day), and DEHP (150 mg/kg body weight/day) combined with BPA (20 mg/kg body weight/day) by gavage for 30 weeks. Additionally, a DEN/MNU/DHPN (DMD)-induced carcinogenesis animal model was also established to assess their effect on tumor promotion. Namely, the other 80 SD rats were separated into another 4 groups: in addition to DMD initiation each group treated with vehicle, DEHP, BPA and the combination of BPA and DEHP respectively. Our data demonstrated that BPA alone or in combination with DEHP may induce hyperplasia of mammary glands, including the proliferation of ductal epithelial cells and an increase in the number of lobules and acinus after a 30-week exposure. Notably, co-exposure to DEHP and BPA increased the incidence and reduced the latency of mammary tumor, which seemed to enhance the susceptibility of carcinogens-induced tumor. Mechanistically, our results supported the hypothesis that exposure to BPA and DEHP might promote breast cancer dependent on Esr1 and HDAC6 as pivotal factors, and further lead to the activation of oncogene c-Myc. Our study suggested that BPA combined with DEHP facilitate the occurrence of mammary tumors, which contributed to advance our understanding in the complex effects of compound exposure to endocrine disrupting chemicals.

Breast Angiosarcoma with a Preoperative Diagnosis of Late Recurrence of Breast Cancer: A Case Report

Angiosarcoma is a malignant mesenchymal tumor characterized by the presence of vascular endothelial cells. Although rare, angiosarcoma developing in the mammary glands has a poor prognosis. We report a case of breast angiosarcoma with a preoperative diagnosis of late recurrence of breast cancer. A 78-year-old woman noticed a tumor in her right breast and visited our hospital. The patient had undergone breast-conserving surgery and axillary lymph node dissection from the right breast 12 years before the visit. The tumor was diagnosed as T4bN0M0, stage IIIB. Anastrozole was administered as postoperative adjuvant therapy for 5 years; the patient also received 50-Gy whole-breast radiation therapy after surgery. Physical examination during her visit revealed an elevated lesion with blue purpura around the nipple in the right breast. We performed breast ultrasound and detected a well-defined 19.6 × 16.4 × 10.7 mm hypoechoic tumor in the left subareolar area. The patient underwent core needle biopsy (CNB). Based on the CNB specimen findings, she was suspected to experience late local recurrence after surgery. Therefore, she underwent total mastectomy after breast-conserving surgery. A dark-red tumor sized 18 × 12 mm was found in a specimen from the nipple. The pathological diagnosis of the specimen revealed short spindle-shaped tumor cells with strong nuclear pleomorphism and a significant interstitial fibrosis. Immunohistochemistry using D2-40 and CD31 antibodies showed irregular luminal proliferation at the anastomosis, infiltration into the surrounding tissue, and massive necrosis, thereby leading to the diagnosis of breast angiosarcoma. We have reported a case of breast angiosarcoma with a preoperative diagnosis of late recurrence of breast cancer.

PDGFRβ is an essential therapeutic target for BRCA1-deficient mammary tumors

BACKGROUND

Basal-like breast cancers (BLBCs) are a leading cause of cancer death due to their capacity to metastasize and lack of effective therapies. More than half of BLBCs have a dysfunctional BRCA1. Although most BRCA1-deficient cancers respond to DNA-damaging agents, resistance and tumor recurrence remain a challenge to survival outcomes for BLBC patients. Additional therapies targeting the pathways aberrantly activated by BRCA1 deficiency are urgently needed.

METHODS

Most BRCA1-deficient BLBCs carry a dysfunctional INK4-RB pathway. Thus, we created genetically engineered mice with Brca1 loss and deletion of p16INK4A, or separately p18INK4C, to model the deficient INK4-RB signaling in human BLBC. By using these mutant mice and human BRCA1-deficient and proficient breast cancer tissues and cells, we tested if there exists a druggable target in BRCA1-deficient breast cancers.

RESULTS

Heterozygous germline or epithelium-specific deletion of Brca1 in p18INK4C- or p16INK4A-deficient mice activated Pdgfrβ signaling, induced epithelial-to-mesenchymal transition, and led to BLBCs. Confirming this role, targeted deletion of Pdgfrβ in Brca1-deficient tumor cells promoted cell death, induced mesenchymal-to-epithelial transition, and suppressed tumorigenesis. Importantly, we also found that pharmaceutical inhibition of Pdgfrβ and its downstream target Pkcα suppressed Brca1-deficient tumor initiation and progression and effectively killed BRCA1-deficient cancer cells.

CONCLUSIONS

Our work offers the first genetic and biochemical evidence that PDGFRβ-PKCα signaling is repressed by BRCA1, which establishes PDGFRβ-PKCα signaling as a therapeutic target for BRCA1-deficient breast cancers.

MMP-7 derived peptides with MHC class-I binding motifs from canine mammary tumor tissue elicit strong antigen-specific T-cell responses in BALB/c mice

Matrix Metalloproteinases (MMPs)-induced altered proteolysis of extracellular matrix proteins and basement membrane holds the key for tumor progression and metastasis. Matrix metalloproteinases-7 (Matrilysin), the smallest member of the MMP family also performs quite alike; thus serves as a potential candidate for anti-tumor immunotherapy. Conversely, being an endogenous tumor-associated antigen (TAA), targeting MMP-7 for immunization is challenging. But MMP-7-based xenovaccine can surmount the obstacle of poor immunogenicity and immunological tolerance, often encountered in TAA-based conventional vaccine for anti-tumor immunotherapy. This paves the way for investigating the potential of MMP-7-derived major histocompatibility complex (MHC)-binding peptides to elicit precise epitope-specific T-cell responses towards their possible inclusion in anti-tumor vaccine formulations. Perhaps it also ushers the path of achieving multiple epitope-based broad and universal cellular immunity. In current experiment, an immunoinformatics approach has been employed to identify the putative canine matrix matelloproteinases-7 (cMMP-7)-derived peptides with MHC class-I-binding motifs which can elicit potent antigen-specific immune responses in BALB/c mice. Immunization with the cMMP-7 DNA vaccine induced a strong CD8⁺ cytotoxic T lymphocytes (CTLs) and Th1- type response, with high level of gamma interferon (IFN-γ) production in BALB/c mice. The two identified putative MHC-I-binding nonameric peptides (Peptide_32-40 and Peptide_175-183) from cMMP-7 induced significant lymphocyte proliferation along with the production of IFN-γ from CD8⁺ T-cells in mice immunized with cMMP-7 DNA vaccine. The current observation has depicted the immunogenic potential of the two cMMP-7-derived nonapeptides for their possible exploitation in xenovaccine-mediated anti-tumor immunotherapy in mouse model.

PIK3CA mutations matter for cancer in dogs

Cancer is a genetic disease that arises from the accumulation of genetic mutations within a cell. Mutations in PIK3CA gene are frequently observed in human solid cancers, and also appear to occur in canine tumors. Specifically, recurrent somatic PIK3CA variants identified in canine mammary tumors and hemangiosarcomas are comparable to human hotspot mutations such as H1047R. PIK3CA mutations found in canine tumors encode functional proteins that may alter downstream PI3K/Akt/mTOR signaling pathway. Therefore, PI3K inhibitors have potential in cancer therapy for dogs. This article concisely reviews the emerging evidence concerning the genetic and molecular properties of PIK3CA mutations to discuss future perspectives in veterinary and comparative oncology.

IL-18 immunoadjuvanted xenogeneic canine MMP-7 DNA vaccine overcomes immune tolerance and supresses the growth of murine mammary tumor

The development of the tumorigenesis and angiogenesis through proteolytic cleavage of extracellular matrix protein and basement membranes is promoted by Matrix metelloproteinases-7 (MMP-7). Consequently, MMP-7 is presumed as potential target for mammary cancer immunotherapy. However, MMP-7 is an endogenous tumor associated antigen (TAA); therefore, immunization is challenging. In current study, a potent anti-tumor immune response has been elicited through recombinant bivalent plasmid pVIVO2.IL18.cMMP7 which subside the highly metastatic 4 T1 cell line induced mammary tumors and efficiently negate the existing challenge of using MMP-7 as immunotherapeutic target. Balb/c mice were immunized with canine MMP-7 (cMMP-7) using interleukine-18 (IL-18), as an immunoadjuvant, to explore the potential of the combination regarding elicitation of a potent anti-tumor immune response. Mice vaccinated with pVIVO2.IL18.cMMP7 DNA plasmid reduced the tumor growth significantly along with augmentation of the immune response to fight against tumor antigen as depicted by substantial enrichment of CD4+ and CD8+ population in splenocytes, infiltration of immune system cells in tumor tissue and enhanced survival time of mice. Further, splenocyte supernatant examination of the cytokines revealed that Th1 cytokines (IFN-γ and IL-2) were remarkably up-regulated demonstrating the stimulation of cell-mediated immune response. Thus the current observations vividly portray that administration of xenogeneic MMP-7 DNA vaccine bypasses the tolerance barrier.

Dietary Selenium Supplementation Does Not Attenuate Mammary Tumorigenesis-Mediated Bone Loss in Male MMTV-PyMT Mice

Bone wasting occurs during the progression of breast cancer and contributes to breast cancer mortality. We evaluated the effect of methylseleninic acid (MSeA), an anti-carcinogenic form of selenium, on bone microstructural changes in the presence of mammary tumors in a male breast cancer model of mouse mammary tumor virus-polyomavirus middle T-antigen (MMTV-PyMT). In this study, we performed microcomputed tomographic analysis of femurs and vertebrae collected from a study showing that dietary supplementation with MSeA reduces mammary tumorigenesis in male mice. Compared to age-matched, non-tumor-bearing mice (MMTV-PyMT negative), the presence of mammary tumors significantly reduced the bone volume fraction, trabecular thickness, and bone mineral density while it increased the structure model index in femurs, but not in vertebrae. Moreover, mammary tumorigenesis decreased plasma concentrations of osteocalcin. Supplementation with MSeA did not affect these changes in MMTV-PyMT mice. In conclusion, mammary tumorigenesis caused bone loss in MMTV-PyMT mice. However, dietary supplementation with MSeA did not attenuate mammary tumor-associated bone loss in this model of male breast cancer.

Carcinogenic potential of fluorinated estrogens in mammary tumorigenesis

Fluorination preventing metabolic hydroxylation of 17β-estradiol (E₂) was applied to investigate the mechanisms underlying estrogen-induced carcinogenesis. Either 2-fluoro-17β-estradiol (2-FE₂) or 4-fluoro-17β-estradiol (4-FE₂) was administered subcutaneously for 52 weeks to August Copenhagen Irish (ACI) rats, the preferred animal model for human breast cancer. 4-FE₂ induced frequent mammary tumors whereas 2-FE₂ did not. The cumulative incidence of mammary tumors in rats treated with 4-FE₂ was comparable to that observed with E₂. The carcinogenic results were supported by histological examination of mammary glands of fluorinated estrogen-treated ACI rats. To evaluate the estrogenic potential of the fluorinated estrogens, 2-FE₂ or 4-FE₂ was administrated subcutaneously to ovariectomized rats. Both 4-FE₂ and 2-FE₂ showed high uterotrophic potency. Our results indicate that estrogenic potential may not be the sole factor driving mammary tumorigenesis. Since fluorination inhibits metabolic hydroxylation of E₂ at the substituted position, the carcinogenic effect may occur through the metabolic activation of 2-hydroxylated E₂, in combination with the compound's estrogenic potency.

Adenoid Cystic Carcinoma of the Breast: A Case Report

Adenoid cystic carcinomas (ACCs) are malignant tumors that most often occur in the salivary glands and bronchi, with occurrence in the breast being rare. ACCs of the breast reportedly give rise to few lymph node metastases or distant metastases and have a favorable prognosis. A 56-year-old woman with a left breast mass identified by mammographic screening was examined at our institute. Breast ultrasound revealed a sharply marginated, hypoechoic mass 12.7 × 9.4 × 8.7 mm in size in the upper outer quadrant of the left breast, and a vacuum-assisted biopsy (VAB) was performed at the mass site. Pathological examination of the VAB specimen revealed atypical cells with a cribriform growth pattern, and mucosal fluid surrounding tumor nests and within tumor ducts. The area around the tumor nests and inside of tumor ducts were also positively stained with alcian blue. These findings, we reached a pathological diagnosis of ACC. The preoperative diagnosis was stage I (cT1N0M0) triple-negative left breast cancer. Surgery consisted of breast-conserving surgery and sentinel node biopsy. The excised specimen was a 15.0 × 12.1 × 9.7 mm mass with a greyish white cut surface. Pathological examination of the excised specimen revealed a so-called adenoid cystic pattern. Results from immunohistochemical staining were identical to those from a VAB specimen, as they were estrogen receptor-negative, progesterone receptors-negative, and human epidermal growth factor receptor 2-negative, with low Ki67 expression. The final diagnosis, given the above findings, was left breast cancer (ACC) pT1N0M0 stage I triple-negative subtype.

Pure Mucinous Breast Carcinoma with Micropapillary Pattern (MUMPC): A Case Report

Pure mucinous breast carcinoma with micropapillary pattern (MUMPC) was proposed as a new histopathological variant of pure mucinous carcinoma (PMC) with tumor cells forming a micropapillary architecture. The Classification of Tumours of the Breast by the World Health Organization, however, does not differentiate MUMPC as a distinct subtype. There is currently no consensus whether tumors that exhibit these features are classified as PMC or invasive micropapillary carcinoma (IMPC) with associated mucin production. A 45-year-old woman was examined for a tumor in her left breast. Upon physical examination, an elastic hard mass of around 5 cm along with accompanying skin flare and ulceration was palpated in the upper outer quadrant of the left breast. Mammary ultrasonography revealed a clearly marginated hypoechoic tumor of 55.0 × 46.9 × 37.0 mm in size in the upper outer quadrant of the left breast. A vacuum-assisted biopsy (VAB) was performed in the same site and histopathological diagnosis of PMC was made. Contrast-enhanced magnetic resonance imaging (MRI) showed a T1W1 low-intensity signal and a T2W1 high-intensity signal at the primary focus, ring enhancement of the tumor margin, and stranding enhancement inside the tumor. A preoperative diagnosis of left breast cancer (PMC), cT4bN1M0, stage IIIB, luminal B-like was made. We performed a simple mastectomy with axillary lymph node dissection. A 55.0 × 48.1 × 37.1 mm tumor with the gelatinous cut surface was excised. Histopathological examination of the excised specimen revealed mucin lake formation in the tumor containing clusters of atypical cells. The atypical cells showed swollen, irregular nuclei and a papillary growth pattern that lead to the diagnosis of MUMPC.

Subphthalocyanine as a fluorescence imaging agent for breast tumor

Tri-tert-butyl-carboxyl subphthalocyanine (SubPc) was synthesized and evaluated as a fluorescence agent. Fluorescence imaging for breast tumor in vivo was performed using nude mice as models. Results indicate high uptake in tumor at 20 h. Tumor-non tumor ratio was determined as 2.25. The imaging results demonstrate the potential of this fluorescence-imaging agent in the diagnosis of breast tumor. In the future, subphthalocyanine is also developing as a dual functional, which is fluorescence imaging and as a photodynamic therapeutic agent for the treatment and diagnosis of cancer.

Long-chain omega-3 polyunsaturated fatty acids decrease mammary tumor growth, multiorgan metastasis and enhance survival

Epidemiological studies show a reduced risk of breast cancer (BC) in women consuming high levels of long-chain (LC) omega-3 (ω-3) fatty acids (FAs) compared with women who consumed low levels. However, the regulatory and mechanistic roles of dietary ω-6 and LC-ω-3 FAs on tumor progression, metastasis and survival are poorly understood. Female BALB/c mice (10-week old) were pair-fed with a diet containing ω-3 or an isocaloric, isolipidic ω-6 diet for 16 weeks prior to the orthotopic implantation of 4T1 mammary tumor cells. Major outcomes studied included: mammary tumor growth, survival analysis, and metastases analyses in multiple organs including pulmonary, hepatic, bone, cardiac, renal, ovarian, and contralateral MG (CMG). The dietary regulation of the tumor microenvironment was evaluated in mice autopsied on day-35 post tumor injection. In mice fed the ω-3 containing diet, there was a significant delay in tumor initiation and prolonged survival relative to the ω-6 diet-fed group. The tumor size on day 35 post tumor injection in the ω-3 group was 50% smaller and the frequencies of pulmonary and bone metastases were significantly lower relative to the ω-6 group. Similarly, the incidence/frequencies and/or size of cardiac, renal, ovarian metastases were significantly lower in mice fed the ω-3 diet. The analyses of the tumor microenvironment showed that tumors in the ω-3 group had significantly lower numbers of proliferating tumor cells (Ki67⁺)/high power field (HPF), and higher numbers of apoptotic tumor cells (TUNEL⁺)/HPF, lower neo-vascularization (CD31⁺ vessels/HPF), infiltration by neutrophil elastase⁺ cells, and macrophages (F4/80⁺) relative to the tumors from the ω-6 group. Further, in tumors from the ω-3 diet-fed mice, T-cell infiltration was 102% higher resulting in a neutrophil to T-lymphocyte ratio (NLR) that was 76% lower (p < 0.05). Direct correlations were observed between NLR with tumor size and T-cell infiltration with the number of apoptotic tumor cells. qRT-PCR analysis revealed that tumor IL10 mRNA levels were significantly higher (six-fold) in the tumors from mice fed the ω-3 diet and inversely correlated with the tumor size. Our data suggest that dietary LC-ω-3FAs modulates the mammary tumor microenvironment slowing tumor growth, and reducing metastases to both common and less preferential organs resulting in prolonged survival. The surrogate analyses undertaken support a mechanism of action by dietary LC-ω-3FAs that includes, but is not limited to decreased infiltration by myeloid cells (neutrophils and macrophages), an increase in CD3⁺ lymphocyte infiltration and IL10 associated anti-inflammatory activity.

BMP9, but not BMP10, acts as a quiescence factor on tumor growth, vessel normalization and metastasis in a mouse model of breast cancer

BACKGROUND

Angiogenesis has become an attractive target for cancer therapy. However, despite the initial success of anti-VEGF (Vascular endothelial growth factor) therapies, the overall survival appears only modestly improved and resistance to therapy often develops. Other anti-angiogenic targets are thus urgently needed. The predominant expression of the type I BMP (bone morphogenetic protein) receptor ALK1 (activin receptor-like kinase 1) in endothelial cells makes it an attractive target, and phase I/II trials are currently being conducted. ALK1 binds with strong affinity to two ligands that belong to the TGF-ß family, BMP9 and BMP10. In the present work, we addressed their specific roles in tumor angiogenesis, cancer development and metastasis in a mammary cancer model.

METHODS

For this, we used knockout (KO) mice for BMP9 (constitutive Gdf2-deficient), for BMP10 (inducible Bmp10-deficient) and double KO mice (Gdf2 and Bmp10) in a syngeneic immunocompetent orthotopic mouse model of spontaneous metastatic breast cancer (E0771).

RESULTS

Our studies demonstrate a specific role for BMP9 in the E0771 mammary carcinoma model. Gdf2 deletion increased tumor growth while inhibiting vessel maturation and tumor perfusion. Gdf2 deletion also increased the number and the mean size of lung metastases. On the other hand, Bmp10 deletion did not significantly affect the E0771 mammary model and the double deletion (Gdf2 and Bmp10) did not lead to a stronger phenotype than the single Gdf2 deletion.

CONCLUSIONS

Altogether, our data show that in a tumor environment BMP9 and BMP10 play different roles and thus blocking their shared receptor ALK1 is maybe not appropriate. Indeed, BMP9, but not BMP10, acts as a quiescence factor on tumor growth, lung metastasis and vessel normalization. Our results also support that activating rather than blocking the BMP9 pathway could be a new strategy for tumor vessel normalization in order to treat breast cancer.

Time-restricted feeding mitigates high-fat diet-enhanced mammary tumorigenesis in MMTV-PyMT mice

Erratic eating behavior disrupts the daily feeding and fasting pattern and leads to metabolic dysfunction and chronic diseases including cancer. In the present study, we tested the hypothesis that time-restricted feeding of a high-fat diet (HFD) to the dark phase does not enhance mammary tumorigenesis in MMTV-PyMT mice. Female mice were assigned to 3 groups and fed the standard AIN93G diet or an HFD with or without dark phase restricted feeding (12 hours). The duration of restricted feeding was 8 weeks. The HFD group had 24% more body fat mass than the AIN93G group; the body fat mass of the restricted group remained similar to that of the AIN93G group. Energy intake of the restricted group was similar to that of the HFD and AIN93G groups. The median mammary tumor latency was 5.8, 7.0, and 6.4 weeks for the AIN93G, HFD, and restricted groups, respectively. Mammary tumor progression was 241% higher in the HFD group than that in the AIN93G group; there was no significant difference in tumor progression between the restricted and AIN93G groups. Plasma concentrations of leptin, monocyte chemoattractant protein-1, plasminogen activator inhibitor-1, angiopoietin-2, vascular endothelial growth factor, and hepatocyte growth factor were significantly higher in the HFD group than those in the control group; these measurements were similar between the restricted and control groups. In conclusion, feeding restricted to the dark phase mitigates the HFD-enhanced mammary tumorigenesis; this may be related to the lower body adiposity and associated inflammatory and angiogenic signals.

Over-expression of mammaglobin-B in canine mammary tumors

Background

Mammaglobin, a member of secretoglobin family has been recognized as a breast cancer associated protein. Though the exact function of the protein is not fully known, its expression has been reported to be upregulated in human breast cancer.We focused on studying the expression of mammaglobin-B gene and protein in canine mammary tumor (CMT) tissue. Expression of mammaglobin-B mRNA and protein were assessed by quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry (IHC), respectively.

Results

High levels of mammaglobin-B mRNA expression (6.663 ± 0.841times) was observed in CMT as compared to age and breed matched healthy controls. Further, expression of mammaglobin-B protein was detected in paraffin-embedded mammary tumor tissues from the same subjects by IHC. Mammaglobin-B protein was overexpressed only in 6.67% of healthy mammary glands while, a high level of its expression was scored in 76.7% of the CMT subjects. Moreover, no significant differences in terms of IHC score and qRT-PCR score with respect to CMT histotypes or tumor grades were observed, indicating that mammaglobin-B over-expression occurred irrespective of CMT types or grades.

Conclusion

Overall, significantly increased expression of mammaglobin-B protein was found in CMTs with respect to healthy mammary glands, which positively correlates to its transcript. These findings suggest that overexpression of mammaglobin-B is associated with tumors of canine mammary glands.

PTEN PDZ-binding domain suppresses mammary carcinogenesis in the MMTV-PyMT breast cancer model

Phosphatase and tension homolog (PTEN) is a potent tumor suppressor that possesses a PDZ-binding domain (PDZ-BD) at the end of its carboxyl terminus, whose functions during tumorigenesis remains unclear. Here, we crossed a mouse strain with germline deletion of PTEN PDZ-BD with MMTV-PyMT breast cancer model, and found that knockout (KO) mice display normal development of mammary glands, but have both increased breast tumorigenicity and lung metastasis. Orthotopic allograft experiments suggest the loss of PTEN PDZ-BD in breast cancer cells rather than in tumor microenvironment plays a prominent role in increasing tumor burden. Through RNA-sequencing, we observed a significant downregulation of myoepithelial marker genes in both KO primary breast cancer and orthotopic allografts. Moreover, these myoepithelial marker genes are significantly downregulated in human breast cancer tissues, and are associated with poorer clinical prognosis. In addition, several homeobox genes were also identified to be downreguated in KO breast cancer, whose expressions showed significant positive correlation with myoepithelial marker genes. Overall, our findings suggest a novel tumor suppressive role of PTEN PDZ-BD in a murine model of breast cancer, and the mechanism involves the dysregulation of homeobox genes which may result in defective myoepithelial differentiation in breast cancer cells.

Modulation of mammary tumor vascularization by mast cells: Ultrasonographic and histopathological approaches

AIMS

The inhibition of mast cells' degranulation may be an approach to prevent the formation of new vessels during the mammary carcinogenesis.

MATERIALS AND METHODS

Female Sprague-Dawley rats were randomly divided into five experimental groups. Mammary tumors were induced by intraperitoneal injection of N-methyl-N-nitrosourea (MNU). Animals from group II were treated with ketotifen for 18weeks immediately after the MNU administration, while animals from group III only received the ketotifen after the development of the first mammary tumor. Mammary tumors vascularization was assessed by ultrasonography (Doppler, B Flow and contrast-enhanced ultrasound) and immunohistochemistry (vascular endothelial growth factor-A).

KEY FINDINGS AND SIGNIFICANCE

Similar to what occurs in women with breast cancer, the majority of MNU-induced mammary tumors exhibited a centripetal enhancement order of the contrast agent, clear margin and heterogeneous enhancement. Ultrasonographic and immunohistochemical data suggest that the inhibition of mast cells' degranulation did not change the mammary tumors vascularization.

High-fat Diet Enhances Mammary Tumorigenesis and Pulmonary Metastasis and Alters Inflammatory and Angiogenic Profiles in MMTV-PyMT Mice

The MMTV-PyMT transgenic mouse model is commonly used to study luminal B subtype, which has a lower prevalence but a worse prognosis than luminal A subtype among patients with breast cancer. The objective of the present study was to determine whether an obesogenic, high-fat diet enhances primary tumorigenesis and pulmonary metastasis in female MMTV-PyMT mice. The high-fat diet slightly but significantly increased caloric intake and body fat mass compared to the AIN93G diet. The high-fat diet significantly increased primary mammary tumor progression by 59%, primary tumor weight by 60%, and the number of lung metastases by 147%. Compared to the AIN93G diet, the high-fat diet significantly increased the abundance of proinflammatory cytokines (e.g. leptin, monocyte chemotactic protein-1, plasminogen activator inhibitor-1, resistin, and tumor necrosis factor-α) and angiogenic factors (e.g. hepatocyte growth factor, tissue inhibitor of metalloproteinase inhibitor-1, and vascular endothelial growth factor) in plasma and mammary tumors. We conclude that the obesogenic high-fat diet enhances primary tumorigenesis and metastasis in MMTV-PyMT mice. This enhancement may be the result of increased proinflammation and angiogenesis signaling.

Antisense Oligonucleotide-mediated Knockdown in Mammary Tumor Organoids

Primary mammary tumor organoids grown in 3D are an excellent system to study tumor biology. They resemble the organization and physiology of native epithelia more closely than cancer cell lines grown in 2D, and additionally model interactions with the ECM (Boj et al., 2015; Clevers, 2016; Shamir and Ewald, 2014). Mammary tumor organoids are therefore a promising model system to identify and characterize novel drivers of breast cancer that would be unlikely to be identified using 2D cell lines. Antisense oligonucleotides can be used to efficiently and specifically knockdown target genes in the cell (Bennett et al., 2017). They can be taken up freely by organoids without the need for a transfection agent, making them a convenient tool for routine lab studies and screens.

The glucose transporter GLUT1 is required for ErbB2-induced mammary tumorigenesis

BACKGROUND

Altered tumor cell metabolism is an emerging hallmark of cancer; however, the precise role for glucose in tumor initiation is not known. GLUT1 (SLC2A1) is expressed in breast cancer cells and is likely responsible for avid glucose uptake observed in established tumors. We have shown that GLUT1 was necessary for xenograft tumor formation from primary mammary cells transformed with the polyomavirus middle-T antigen but that it was not necessary for growth after tumors had formed in vivo, suggesting a differential requirement for glucose depending on the stage of tumorigenesis.

METHODS

To determine whether GLUT1 is required early during mammary tumorigenesis, we crossed MMTV-NIC mice, which express activated HER2/NEU/ERBB2 and Cre recombinase, to Slc2a1 ^Flox/Flox (GLUT1^Flox/Flox) mice to generate NIC-GLUT1^+/+, NIC-GLUT1^Flox/+, and NIC-GLUT1^Flox/Flox mice. In addition, we evaluated effects of glucose restriction or GLUT1 inhibition on transformation in MCF10A-ERBB2 breast epithelial cells in three-dimensional culture. Finally, we utilized global gene expression profiling data of primary human breast tumors to determine the relationship between SLC2A1 and stage of tumorigenesis.

RESULTS

All of the NIC-GLUT1^+/+ mice developed tumors in less than 200 days. In contrast, only 1 NIC-GLUT1^Flox/Flox mouse and 1 NIC-GLUT1^Flox/+ mouse developed mammary tumors, even after 18 months. Mammary gland development was not disrupted in NIC mice lacking GLUT1; however, epithelial content of mature glands was reduced compared to NIC-GLUT1^Flox/+ mice. In MCF10A-ERBB2 cells, glucose restriction or GLUT1 inhibition blocked transformation induced by activated ERBB2 through reduced cell proliferation. In human breast cancers, SLC2A1 was higher in ductal carcinoma in situ compared to the normal breast, but lower in invasive versus in situ lesions, suggesting the requirement for GLUT1 decreases as tumors progress.

CONCLUSIONS

This study demonstrates a strict requirement for GLUT1 in the early stages of mammary tumorigenesis in vitro and in vivo. While metabolic adaptation has emerged as a hallmark of cancer, our data indicate that early tumor cells rely heavily on glucose and highlight the potential for glucose restriction as a breast cancer preventive strategy.

Does native Trypanosoma cruzi calreticulin mediate growth inhibition of a mammary tumor during infection?

BACKGROUND

For several decades now an antagonism between Trypanosoma cruzi infection and tumor development has been detected. The molecular basis of this phenomenon remained basically unknown until our proposal that T. cruzi Calreticulin (TcCRT), an endoplasmic reticulum-resident chaperone, translocated-externalized by the parasite, may mediate at least an important part of this effect. Thus, recombinant TcCRT (rTcCRT) has important in vivo antiangiogenic and antitumor activities. However, the relevant question whether the in vivo antitumor effect of T. cruzi infection is indeed mediated by the native chaperone (nTcCRT), remains open. Herein, by using specific modified anti-rTcCRT antibodies (Abs), we have neutralized the antitumor activity of T. cruzi infection and extracts thereof, thus identifying nTcCRT as a valid mediator of this effect.

METHODS

Polyclonal anti-rTcCRT F(ab')2 Ab fragments were used to reverse the capacity of rTcCRT to inhibit EAhy926 endothelial cell (EC) proliferation, as detected by BrdU uptake. Using these F(ab')2 fragments, we also challenged the capacity of nTcCRT, during T. cruzi infection, to inhibit the growth of an aggressive mammary adenocarcinoma cell line (TA3-MTXR) in mice. Moreover, we determined the capacity of anti-rTcCRT Abs to reverse the antitumor effect of an epimastigote extract (EE). Finally, the effects of these treatments on tumor histology were evaluated.

RESULTS

The rTcCRT capacity to inhibit ECs proliferation was reversed by anti-rTcCRT F(ab')2 Ab fragments, thus defining them as valid probes to interfere in vivo with this important TcCRT function. Consequently, during infection, these Ab fragments also reversed the in vivo experimental mammary tumor growth. Moreover, anti-rTcCRT Abs also neutralized the antitumor effect of an EE, again identifying the chaperone protein as an important mediator of this anti mammary tumor effect. Finally, as determined by conventional histological parameters, in infected animals and in those treated with EE, less invasive tumors were observed while, as expected, treatment with F(ab')2 Ab fragments increased malignancy.

CONCLUSION

We have identified translocated/externalized nTcCRT as responsible for at least an important part of the anti mammary tumor effect of the chaperone observed during experimental infections with T. cruzi.

CD24 cell surface expression in Mvt1 mammary cancer cells serves as a biomarker for sensitivity to anti-IGF1R therapy

Background

The pro-tumorigenic effects of the insulin-like growth factor receptor (IGF1R) are well described. IGF1R promotes cancer cell survival and proliferation and prevents apoptosis, and, additionally it was shown that IGF1R levels are significantly elevated in most common human malignancies including breast cancer. However, results from phase 3 clinical trials in unselected patients demonstrated lack of efficacy for anti-IGF1R therapy. These findings suggest that predictive biomarkers are greatly warranted in order to identify patients that will benefit from anti-IGF1R therapeutic strategies.

Methods

Using the delivery of shRNA vectors into the Mvt1 cell line, we tested the role of the IGF1R in the development of mammary tumors. Based on CD24 cell surface expression, control and IGF1R-knockdown (IGF1R-KD) cells were FACS sorted into CD24⁻ and CD24⁺ subsets and further characterized in vitro. The tumorigenic capacity of each was determined following orthotopic inoculation into the mammary fat pad of female mice. Tumor cells were FACS characterized upon sacrifice to determine IGF1R effect on the plasticity of this cell’s phenotype. Metastatic capacity of the cells was assessed using the tail vein assay.

Results

In this study we demonstrate that downregulation of the IGF1R specifically in cancer cells expressing CD24 on the cell surface membrane affect both their morphology (from mesenchymal-like into epithelial-like morphology) and phenotype in vitro. Moreover, we demonstrate that IGF1R-KD abolished both CD24⁺ cells capacity to form mammary tumors and lung metastatic lesions. We found in both cells and tumors a marked upregulation in CTFG and a significant reduction of SLP1 expression in the CD24⁺/IGF1R-KD; tumor-suppressor and tumor-promoting genes respectively.

Moreover, we demonstrate here that the IGF1R is essential for the maintenance of stem/progenitor-like cancer cells and we further demonstrate that IGF1R-KD induces in vivo differentiation of the CD24⁺ cells toward the CD24^- phenotype. This further supports the antitumorigenic effects of IGF1R-KD, as we recently published that these differentiated cells demonstrate significantly lower tumorigenic capacity compared with their CD24⁺ counterparts.

Conclusions

Taken together these findings suggest that CD24 cell surface expression may serve as a valuable biomarker in order to identify mammary tumors that will positively respond to targeted IGF1R therapies.

Electronic supplementary material

The online version of this article (doi:10.1186/s13058-016-0711-7) contains supplementary material, which is available to authorized users.

Combined administration of the apoptin gene and poly (I:C) induces potent anti-tumor immune response and inhibits growth of mouse mammary tumors

BACKGROUND

Many viral proteins exhibit selective cytotoxicity for tumor cells without affecting the normal diploid cells. The apoptin protein of chicken infectious anemia virus is one of such proteins, which has been shown to kill tumor cells specifically. However, an effective cancer treatment strategy also requires assistance from the immune system. Recently, poly (I:C) has been shown to be an effective cancer vaccine adjuvant.

AIM

In this study, we assessed the anti-tumor potential of apoptin gene transfer alone and in combination with poly (I:C) in a 4T1 mouse mammary tumor model.

METHODS

4T1 cells were used to induce mammary tumor in Balb/c mice. Mice bearing tumors were divided into 6 groups, and each group received six intratumoral injections during a period of one month. After the last immunization, the animals were sacrificed, and peripheral blood, spleen, lungs, liver, heart, kidney and tumor tissues were collected for immunological, molecular and pathological analysis.

RESULTS

We report that intratumoral administration of apoptin plasmid along with poly (I:C) not only significantly inhibited the growth of mammary tumor, but also induced a potent anti-tumor immune response as indicated by the increase in blood CD4+, CD8+ cells and infiltration of immune cells in the tumor tissue. Further, blood serum analysis of the cytokines revealed increased secretion of Th1 cytokines (IFN-γ and IL-2).

CONCLUSIONS

The results of our study demonstrate that the inclusion of poly (I:C) significantly enhanced the anti-tumor activity of apoptin mainly by inducing a potent anti-tumor immune response. Therefore, we report the use of apoptin and poly (I:C) combination as a novel and powerful strategy for cancer immunotherapy.

Evaluation of apoptosis-associated protein (Bcl-2, Bax, cleaved caspase-3 and p53) expression in canine mammary tumors: An immunohistochemical and prognostic study

Apoptosis is an important process involved in pathogenesis and progression of neoplasia. However, it has been not so far extensively investigated in canine mammary tumors (CMTs). Therefore the aim of our study was to determine Bcl-2, Bax, cleaved caspase-3 (CC3) and p53 expression in CMTs and evaluate their correlation with host/tumor factors, and overall survival (OS). Bcl-2 expression was often found in benign lesions and in patients with low TNM stage. Expression of Bax, CC3 and p53 was observed in malignant CMTs. The expression of apoptosis-associated proteins was not significantly associated with OS. A positive-p53 status was significantly related with poorer tumor differentiation, higher mitotic index (MI), more invasive growth, necrosis, and occurred often in CMTs from large breed dogs. In the shorter-survival group of dogs (≤18 months), a positive correlation was found between CC3 and Bcl-2 expression; CC3 and MI, ERα and p53 expression, while in the longer-survival group (>18 months) CC3 expression was negatively correlated with ERα, whereas p53 expression was positively correlated with MI. We confirmed the usefulness of such parameters as: tumor size, MI, type of growth, tumor metastasis and TNM stage in predicting OS in a univariate analysis. In multivariate analysis we identified age as an independent prognostic factor for OS. Expression of single apoptosis-associated protein should not be used as a prognostic marker. However, we showed significant correlation patterns of expression of proteins involved in apoptotic-signaling pathways in shorter- and longer survival groups. So far, there have been only a few similar reports published.

TGIF function in oncogenic Wnt signaling

Transforming growth-interacting factor (TGIF) has been implicated in the pathogenesis of many types of human cancer, but the underlying mechanisms remained mostly enigmatic. Our recent study has revealed that TGIF functions as a mediator of oncogenic Wnt/β-catenin signaling. We found that TGIF can interact with and sequesters Axin1 and Axin2 into the nucleus, thereby culminating in disassembly of the β-catenin-destruction complex and attendant accumulation of β-catenin in the nucleus, where it activates expression of Wnt target genes, including TGIF itself. We have provided proof-of-concept evidences that high levels of TGIF expression correlate with poor prognosis in patients with triple negative breast cancer (TNBC), and that TGIF empowers Wnt-driven mammary tumorigenesis in vivo. Here, we will briefly summarize how TGIF influences Wnt signaling to promote tumorigenesis.

Anti-tumorigenic effect of nano formulated peptide pACC1 by diminishing de novo lipogenisis in DMBA induced mammary carcinoma rat model

At present, the majority of established treatments for breast cancer are based on clinical manifestations, some fundamental of molecular and cellular biology of cancer. In recent times, the therapy is moving towards personalized medicines. Nevertheless, both the methodologies have own demerits. In the present study, we proposed a novel idea of targeted therapy with twin pharmacological potential by a peptide pACC1. The peptide was formulated with chitosan and evaluated with DMBA induced mammary carcinoma. Results suggest that the peptide holds great control on tumor cell multiplication, fatty acid synthesis and lactate levels. In addition, peptide also brings normal metabolic signs in glycolytic and glycogenic pathways. Histological studies confirm the dual pharmacological actions. Further, it is also proven that the peptide controls membrane receptor levels of HER2 and EGFR. In conclusion, that the peptide pACC1 could be employed as greater therapeutic adjuvant with currently established drugs without considering the stage of the cancer.

Classification and grading of canine malignant mammary tumors

Histological grading is a good parameter to stratify tumors according to their biological aggressiveness. The Elston and Ellis grading method in humans, invasive ductal breast carcinomas and other invasive tumors are routinely used. The aims of this study were classification of mammary gland tumors and also application of a human grading method in canine mammary carcinoma. The samples included 37 tumors of mammary glands. Mammary tumors were carcinomas (n = 32) and sarcomas (n = 5). The carcinomas were classified as simple carcinoma 56.8% (n = 21), complex carcinoma 13.5% (n = 5), carcinoma arising from benign tumor 10.8% (n= 4) and special type of carcinoma 5.4% (n = 2). Out of 32 carcinomas studied, 37.5% (n = 12) grade I, 46.9% (n = 15) grade II and 15.6% (n = 5) grade III. This study demonstrated that the Elston and Ellis method of histological grading in canine mammary tumor is a reliable prognostic factor which is correlated with histopathological classification.