Tamoxifen inhibits transforming growth factor-α gene expression in human breast carcinoma samples treated with triiodothyronine

Objectives: To examine the effects of triiodothyronine (T3), 17β-estradiol (E2), and tamoxifen (TAM) on transforming growth factor (TGF)-α gene expression in primary breast cancer cell cultures and interactions between the different treatments. Methods and results: Patients included in the study (no.=12) had been newly diagnosed with breast cancer. Fresh human breast carcinoma tissue was cut into 0.3-mm slices. These slices were placed in six 35-mm dishes on 2-ml organ culture medium. Dishes received the following treatments: dish 1: ethanol; dish 2: T3; dish 3: T3+TAM; dish 4: TAM; dish 5: E2; dish 6: E2+TAM. TGF-α mRNA content was normalized to glyceraldehyde-3-phosphate dehydrogenase mRNA levels. All tissues included in this study were positive for estrogen receptor (ER) and thyroid hormone receptor expression. Treatment with T3 for 48 h significantly increased TGF-α mRNA levels compared to controls (15-fold), and concomitant treatment with TAM reduced expression to 3.4-fold compared to controls. When only TAM was added to the culture medium, TGF-α mRNA expression increased 5.3-fold, significantly higher than with all other treatment modalities. Conclusion: We demonstrate that TGF-α mRNA expression is more efficiently upregulated by T3 than E2. Concomitant treatment with TAM had a mitigating effect on the T3 effect, while E2 induced TGF-α upregulation. Our findings show some similarities between primary culture and breast cancer cell lines, but also some important differences: a) induction of TGF-α, a mitogenic protein, by TAM; b) a differential effect of TAM that may depend on relative expression of ER α and β; and c) supraphysiological doses of T3 may induce mitogenic signals in breast cancer tissue under conditions of low circulating E2. ©2008, Editrice Kurtis.

Immunohistochemical expression of PCNA, p53, bax and bcl-2 in oral lichen planus and epithelial dysplasia.

The potential for malignant transformation of oral lichen planus is still controversial. The expression of proteins related to cell proliferation and apoptosis in oral lichen planus and epithelial dysplasia was analyzed to evaluate the true potential for malignant transformation of this disease. Twenty-four cases of each lesion were subjected to the streptoavidin-biotin technique for identifying the immunohistochemical expression of PCNA, p53, bax, and bcl-2 proteins. Of the 24 cases of oral lichen planus, 14 (58.33%) were positive for PCNA, 10 (41.67%) for p53, 4 (16.67%) for bcl-2 and 12 (50%) for bax, whereas of the 24 cases of epithelial dysplasia, 20 (83.33%) were positive for PCNA, 10 (41.67%) for p53, 6 (25%) for bcl-2, and 20 (83.33%) for bax. Chi-squared test showed no statistically significant differences between the expression of p53 and bcl-2 in oral lichen planus and epithelial dysplasia, regardless of the grade (P > 0.05). However, the expression of PCNA and bax was significantly increased in epithelial dysplasia (P < 0.05). The results of this study showed that alterations in expression of these proteins are observed in oral lichen planus and epithelial dysplasia, suggesting the potential for malignant transformation in both lesions.

Highlights from the I international symposium of thrombosis and anticoagulation in internal medicine, October 23-25, 2008, Sao Paulo, Brazil

The importance of thrombosis and anticoagulation in clinical practice is rooted firmly in several fundamental constructs that can be applied both broadly and globally. Awareness and the appropriate use of anticoagulant therapy remain the keys to prevention and treatment. However, to assure maximal efficacy and safety, the clinician must, according to the available evidence, choose the right drug, at the right dose, for the right patient, under the right indication, and for the right duration of time. The first International Symposium of Thrombosis and Anticoagulation in Internal Medicine was a scientific program developed by clinicians for clinicians. The primary objective of the meeting was to educate, motivate and inspire internists, cardiologists and hematologists by convening national and international visionaries, thought-leaders and dedicated clinician-scientists in Sao Paulo, Brazil. This article is a focused summary of the symposium proceedings. © Springer Science+Business Media, LLC 2009.

Occurrence and expression of p53 suppressor gene and c-Myc oncogene in dog eyelid tumors

Purpose: To detect the occurrence and expression of the suppressor gene p53 and of the oncogene c-Myc in eyelid tumors of dogs using the PCR, RT-PCR, PCR-ELISA and RT-PCR-ELISA techniques. These genes have not been described in dog eyelid tumors before. Methods: Nine samples of eyelid or third eyelid epithelial tumors were obtained from the archives of the Department of Veterinary Pathology. Tumor diagnosis was confirmed by evaluation of hematoxylin-eosin stained sections, and immunohistochemistry for cytokeratin AE1/AE3 and vimentin V9. A canine mammary tumor was used for positive control. Agarose gel electrophoresis, PCR-ELISA and RT-PCR-ELISA were used to detect p53 and c-Myc genes. Results: The occurrence of p53 was detected in most of the eyelid tumors and third eyelid tumors studied (88.8%, n = 8) and was expressed in 75% of the positive samples, as indicated by ELISA. The c-Myc gene was found in 77.7% (n = 7) of the samples and was expressed in eight samples. Conclusions: Eyelid and third eyelid tumors of dogs express both the p53 and the c-Myc genes as shown by PCR and RT-PCR. However, PCR ELISA and RT-PCR ELISA were more efficient in assessing occurrence and expression of these genes because they identified amplified products that were not detected by agarose gel electrophoresis. © 2010 American College of Veterinary Ophthalmologists.

COX-2 and TGF-β expression in proliferative disorders of canine prostate

COX-2 and TGF-β expression was determined in order to correlate non-neoplastic lesions, preneoplastic lesions and carcinoma in the prostate of dogs. The results show that neoplastic and preneoplastic lesions express more COX-2 and TGF-β when compared to carcinomas, which suggests these proteins may cooperate in the process of prostate tumorigenesis.

Cherubism: Clinical case and genetic standpoints

Cherubism is a rare non-neoplastic hereditary disease, characterized by bilateral bone enlargement of the jaws and is accompanied by inflammation and fibrosis in childhood. An increase in jaw size is noted, with maximum enlargement occurring within 2 years of onset in most cases. By age 7, the lesions become static or progress relatively slowly until puberty. During the late teens, the disease may undergo spontaneous involution. The present case show a patient with history of bilateral enlargement of the jaw with the triad of clinical, histological and radiological findings that helps in the final diagnosis of cherubism.

Cytoplasmic and nuclear morphometric parameters in cytologic preparations of canine cutaneous mast cell tumors

Thirty fine-needle biopsy (FNB) samples from 28 dogs subjected to surgical resection of cutaneous mast cell tumors (MCTs) were stained with Giemsa. At least 100 neoplastic cells from each cytology slide were evaluated by morphometric analysis. The parameters were: area, perimeter of the cell, cytoplasm, nucleus and circumference factor. MCTs of grade III had a mean cellular area of 231.70 μm2 ± 57.1, and grade II had a mean of 252.30 μm2 ± 55.0. Cellular perimeter was 61.20 ± 7.1 in grade II and 59.1 ± 8.6 in grade III. Cellular parameters were not statistically different between grades (p>.05). Mean nuclear area was 88.90 μm2 ± 19 in grade III and 72.30 μm2 ± 13.9 in grade II, with statistical difference between grades (P =.011). Mean nuclear perimeter was 32.40 ìm ± 3.0 in grade II and 35.70 ìm ± 4.0 in grade III, with statistical difference between grades (P =.018). Mean nuclear circumference factor was 1.0 ± 0.33 in grade II and 1.1 ± 0.28 in grade III, with no statistical difference between grades (P = 0.78). Nuclear-tocytoplasmic ratio in grade II was 0.29 ±.07 and 0.39 ±.08 in grade III, with statistical difference (P =.02). The number of binucleated and multinucleated cells and mitotic figures was significantly increased in grade III MCTs (P <.001). In conclusion, the number of mitotic figures, presence of binucleation and multinucleation, and nuclear-to-cytoplasmic ratio can help to guide a profile of MCT aggressiveness in cytologic preparations.

Genetic and modifying factors that determine the risk of brain tumors

Some modifying factors may determine the risk of brain tumors. Until now, it could not be attempted to identify people at risk and also to improve significantly disease progression. Current therapy consists of surgical resection, followed by radiation therapy and chemotherapy. Despite of these treatments, the prognosis for patients is poor. In this review, we highlight general aspects concerning genetic alterations in brain tumors, namely astrocytomas, glioblastomas, oligodendrogliomas, medulloblastomas and ependymomas. The influence of these genetic alterations in patients' prognosis is discussed. Mutagen sensivity is associated with cancer risk. The convincing studies that linked DNA damages and DNA repair alterations with brain tumors are also described. Another important modifying factor is immunity. General immune response against cancer, tumor microenvironment and immune response, mechanisms of tumor escape, CNS tumor immunology, immune defects that impair anti-tumor systemic immunity in brain tumor patients and local immunosuppressive factors within CNS are also reviewed. New hope to treatment perspectives, as dendritic-cell-based vaccines is summarized too. Concluding, it seems well established that there is association between brain tumor risk and mutagen sensivity, which is highly heritable. Primary brain tumors cause depression in systemic host immunity; local immunosuppressive factors and immunological characteristics of tumor cells may explain the poor prognosis and DNA damages responses can alert immune system. However, it is necessary to clarify if individuals with both constitutional defects in immune functions and genetic instability have higher risk of developing brain tumors. Cytogenetic prospective studies and gene copy number variations analysis also must be performed in peripheral lymphocytes from brain tumor patients. © 2011 Bentham Science Publishers Ltd.

Evaluation of Agaricus blazei in vivo for antigenotoxic, anticarcinogenic, phagocytic and immunomodulatory activities

The development of various types of cancer results from the interaction among endogenous, environmental and hormonal factors, where the most notable of these factors is diet. The aim of the present study was to determine the antigenotoxic, anticarcinogenic, phagocytic and immunomodulatory activities of Agaricus blazei. The test antigenotoxicity (Comet Assay) and anticarcinogenic (Test of Aberrant Crypt Foci) assess changes in DNA and/or intestinal mucosa that correlate to cancer development. Tests of phagocytosis in the spleen and differential count in blood cells allow the inference of modulation of the immune system as well as to propose a way of eliminating cells with DNA damage. Supplementation with the mushroom was carried out under pre-treatment, simultaneous treatment, post-treatment and pre-treatment. +. continuous conditions. Statistical analysis demonstrated that the mushroom did not have genotoxic activity but showed antigenotoxic activity. Supplementation caused an increase in the number of monocytes and in phagocytic activity, suggesting that supplementation increases a proliferation of monocytes, consequently increasing phagocytic capacity especially in the groups pre-treatment, simultaneous and pre-treatment. +. continuous. The data suggest that A. blazei could act as a functional food capable of promoting immunomodulation which can account for the destruction of cells with DNA alterations that correlate with the development of cancer, since this mushroom was demonstrated to have a preventive effect against pre-neoplastic colorectal lesions evaluated by the aberrant crypt foci assay. According to these results and the literature, it is believed that supplementation with A. blazei can be an efficient method for the prevention of cancer as well as possibly being an important coadjuvant treatment in chemotherapy. © 2011 Elsevier Inc.

Intravascular lymphomatosis in the central nervous system of dogs: Immunohistochemical investigation in two cases

We report here two postmortem cases of dogs with intravascular lymphomatosis affecting the central nervous system. Intravascular lymphomatosis is represented by an exclusively intravascular proliferation of neoplastic lymphoid cells. To characterize the origin of the neoplastic cells, we have proceeded with immunohistochemical analysis to identify B and T lymphocytes and endothelial cells. The results showed predominance of cells from the T cell lineage, and no evidence of B cell origin was found. Few cells from one dog also exhibited cytoplasmatic staining for vimentin and Von Willebrand factor. Although in one case some immunophenotype diversity was observed, the massive presence of CD3 positive cells confirmed these neoplasms as intravascular lymphomatosis of T cell origin.

Papel da proteína Mx1 na resposta a interferons e no processo neoplásico

The Mx1 protein is encoded by an interferon- induced gene and shares domain organization, homooligomerization capacity and membrane association with the large dynamin-like GTPases. The Mx1 protein is involved in the response to a large number of RNA viruses, such as the bunyavirus family and the influenza virus. Interestingly, it has also been found as a methylation-silenced gene in several types of neoplasm, including head and neck squamous cell carcinoma. In this scenario, MX1 gene silencing is associated with immortalization in several neoplastic cell lines. Thus, Mx1 stands out as one of the key proteins involved in interferon-induced immune response and also plays an important role in cell cycle control. Here we discuss some of the functions of the Mx1 protein, including its antiviral activity, protein folding and involvement in neoplasia, as well as those revealed by investigating its cellular partners.

Homeobox gene expression profile indicates HOXA5 as a candidate prognostic marker in oral squamous cell carcinoma

The search for molecular markers to improve diagnosis, individualize treatment and predict behavior of tumors has been the focus of several studies. This study aimed to analyze homeobox gene expression profile in oral squamous cell carcinoma (OSCC) as well as to investigate whether some of these genes are relevant molecular markers of prognosis and/or tumor aggressiveness. Homeobox gene expression levels were assessed by microarrays and qRT-PCR in OSCC tissues and adjacent non-cancerous matched tissues (margin), as well as in OSCC cell lines. Analysis of microarray data revealed the expression of 147 homeobox genes, including one set of six at least 2-fold up-regulated, and another set of 34 at least 2-fold down-regulated homeobox genes in OSCC. After qRT-PCR assays, the three most up-regulated homeobox genes (HOXA5, HOXD10 and HOXD11) revealed higher and statistically significant expression levels in OSCC samples when compared to margins. Patients presenting lower expression of HOXA5 had poorer prognosis compared to those with higher expression (P=0.03). Additionally, the status of HOXA5, HOXD10 and HOXD11 expression levels in OSCC cell lines also showed a significant up-regulation when compared to normal oral keratinocytes. Results confirm the presence of three significantly upregulated (>4-fold) homeobox genes (HOXA5, HOXD10 and HOXD11) in OSCC that may play a significant role in the pathogenesis of these tumors. Moreover, since lower levels of HOXA5 predict poor prognosis, this gene may be a novel candidate for development of therapeutic strategies in OSCC.

Visceral mast cell tumor and mastocythemia in a dog

Mast cell tumor manifests as a localized proliferation of mast cells in the skin, or less frequently as a systemic disorder, which may be accompanied by the presence of neoplastic mast cells in the peripheral blood (mastocythemia). In some cases, the neoplastic circulating mast cells originate in the bone marrow, designated as mast cell leukemia, rarely observed in dogs, or the cells may arise from visceral mast cell tumors, characterizing systemic mastocytosis. The aim of this report was to describe a case of a six-year-old female German shepherd dog presenting with history of anorexia, hematemesis and diarrhea. The blood work revealed intense mastocythemia (43%), with degranulated mast cells, and anisocytosis. At necropsy, white nodular lesions in the thymic region and an infiltrative mass in mesenteric and abdominal lymph nodes were observed. Those lymph nodes were enlarged and off-white. Histopathological examination revealed neoplastic mast cells in the liver, spleen, lymph nodes, kidneys, lungs, gastric and enteric mucosae, and adrenal glands. The clinical, hematological and histopathological findings were compatible with mastocythemia, associated with a moderately differentiated visceral mast cell tumor.

Caracterização imunoistoquímica de neoplasias de bexigas associadas à hematúria enzoótica bovina

Bovine enzootic hematuria is characterized by the development of hemangiomatous lesions from several types of neoplastic processes, from epithelial and mesenchymal origin. In this research the histogenesis of neoplastic lesions found in bladder of bovines with enzootic hematuria from Caparaó microregion in the state of Espírito Santo, Brazil was determined. To accomplish this objective, immunohistochemical analysis was performed with primary antibodies: anti-vimentin, anti-cytokeratin, anti-CD31 and anti-uroplakin. Neoplasms found included urothelial carcinoma, in situ carcinoma, adenocarcinoma, hemangioma, myxoma e hemangiosarcoma. Immunohistochemical staining of cytokeratin in epithelial neoplasms and vimentin in mesenchymal neoplasms was significant (p<0.05). CD31 was positive in all the vessels of all samples, however, the staining was significant (p<0.05) in the tumor endothelial cells of the vascular mesenchymal neoplasms, as in hemangiomas and hemangiosarcomas. Uroplakin III staining was uneven in several neoplastic types and showed no significant difference (p>0.05). Most neoplasms showed an atypical uroplakin staining on urothelium and, in the case of hemangiosarcomas there was no staining of the urothelium at all. The Spearman statistical analysis revealed a positive correlation (r= 0.63, p= 0.05) between CD31 and vimentin and between cytokeratin and uroplakin (rs= -0.61, p= 0.05). It was concluded that biomarkers anti-cytokeratin, anti-vimentin and anti-CD31 are important for the diagnosis of neoplasms epithelial, mesenchymal and vascular mesenchymal, respectively. It is possible to use vimentin and CD31 in association in vascular mesenchymal neoplasms and cytokeratin and uroplakin in epithelial neoplasms. The uroplakin is an effective marker, not only for tumor diagnosis, but also to evaluate the urothelial integrity.

Overexpression of ANXA1 in Penile Carcinomas Positive for High-Risk HPVs

The incidence of penile cancer varies between populations but is rare in developed nations. Penile cancer is associated with a number of established risk factors and associated diseases including phimosis with chronic inflammation, human papillomavirus (HPV) infection, poor hygiene and smoking. The objective of this study was to identify genes related to this type of cancer. The detection of HPV was analyzed in 47 penile squamous cell carcinoma samples. HPV DNA was detected in 48.9% of penile squamous cell carcinoma cases. High-risk HPV were present in 42.5% of cases and low-risk HPV were detected in 10.6% of penile squamous cell carcinomas. The RaSH approach identified differential expression of Annexin A1 (ANXA1), p16, RPL6, PBEF1 and KIAA1033 in high-risk HPV positive penile carcinoma; ANXA1 and p16 were overexpressed in penile squamous cells positive for high-risk HPVs compared to normal penile samples by qPCR. ANXA1 and p16 proteins were significantly more expressed in the cells from high-risk HPV-positive penile carcinoma as compared to HPV-negative tumors (p<0.0001) independently of the subtype of the carcinoma. Overexpression of ANXA1 might be mediated by HPV E6 in penile squamous cell carcinoma of patients with high-risk HPVs, suggesting that this gene plays an important role in penile cancer. © 2013 Calmon et al.