Interleukin 10 expression is related to aggressiveness and poor prognosis of patients with thyroid cancer.

Most patients with thyroid cancer will evolve very well with current therapies. However, 10-30% of these patients will present recurrent disease and some of them will eventually die. IL-10 is an anti-inflammatory and immunosuppressive cytokine that can contribute to the immune escape of neoplastic cells. We aimed to investigate IL-10 as a molecular marker to improve the clinical management of patients with thyroid cancer. We retrospectively studied 162 patients with follicular cell-derived thyroid cancer who attended to our institution, including 63 classic papillary thyroid carcinomas, 46 follicular variant of papillary thyroid carcinomas, 11 poorly differentiated thyroid carcinomas and 42 follicular thyroid carcinomas. Patients were treated according to current guidelines and followed-up for 1-150 months. Additionally, we studied 96 samples of non-malignant tissues. We investigated the expression of IL-10 in tumor cells by semiquantitative and quantitative methods. Malignant tissues presented higher positivity (0.773 ± 0.140) than non-malignant samples (0.623 ± 0.190; p < 0.001). Tumors with extrathyroidal invasion at diagnosis presented higher levels of positivity for IL-10 (0.802 ± 0.125) than tumors without extrathyroidal invasion (0.731 ± 0.147; p = 0.004). We observed a positive correlation between tumor size and IL-10 positivity (correlation coefficient = 0.407; p < 0.001). Patients with IL-10 positivity above the median presented lower relapse-free survival rate compared to those patients whose tumors presented IL-10 positivity below the median. We suggest that a simple IL-10 IHC analysis could help selecting patients who would benefit from a more intensive approach.

Role of Fos-related antigen 1 in the progression and prognosis of ductal breast carcinoma.

AIMS: Fos-related antigen 1 (Fra-1) is a member of the activator protein 1 (AP-1) transcription factor family. Our objective was to evaluate the role of Fra-1 expression in breast carcinoma progression and prognosis. METHODS AND RESULTS: Fra-1 expression was investigated by immunohistochemistry in two tissue microarrays containing, respectively, 85 ductal carcinoma in situ (DCIS) and 771 invasive ductal carcinoma (IDC) samples. Staining was observed in the nucleus and cytoplasm of the carcinomas, but only nuclear staining was considered to be positive. Fibroblasts associated with IDC were also Fra-1-positive. The frequency of Fra-1 positivity in IDC (22.8%) was lower than that in DCIS (42.2%). No association was found between Fra-1 and clinico-pathological variables in DCIS. In IDC, Fra-1 expression correlated with aggressive phenotype markers, including: high grade, oestrogen receptor negativity and human epidermal growth factor receptor 2 (HER-2) positivity (P=0.001, 0.015 and 0.004, respectively), and marginally with the presence of metastasis (P=0.07). Fra-1 was more frequently positive in basal-like (34%) and in HER-2-positive (38.5%) subtypes than in luminal subtypes. Fra-1 presence did not correlate with survival. CONCLUSIONS: A high frequency of Fra-1 in DCIS tumours may be associated with early events in breast carcinogenesis. Although Fra-1 expression correlated with features of a more aggressive phenotype in IDC, no relationship with overall survival was found.

Platelet-activating factor receptor (PAF-R)-dependent pathways control tumour growth and tumour response to chemotherapy.

BACKGROUND: Phagocytosis of apoptotic cells by macrophages induces a suppressor phenotype. Previous data from our group suggested that this occurs via Platelet-activating factor receptor (PAF-R)-mediated pathways. In the present study, we investigated the impact of apoptotic cell inoculation or induction by a chemotherapeutic agent (dacarbazine, DTIC) on tumour growth, microenvironmental parameters and survival, and the effect of treatment with a PAF-R antagonist (WEB2170). These studies were performed in murine tumours: Ehrlich Ascitis Tumour (EAT) and B16F10 melanoma. METHODS: Tumour growth was assessed by direct counting of EAT cells in the ascitis or by measuring the volume of the solid tumour. Parameters of the tumour microenvironment, such as the frequency of cells expressing cyclo-oxygenase-2 (COX-2), caspase-3 and galectin-3, and microvascular density, were determined by immunohistochemistry. Levels of vascular endothelium growth factor (VEGF) and prostaglandin E2 (PGE2) were determined by ELISA, and levels of nitric oxide (NO) by Griess reaction. PAF-R expression was analysed by immunohistochemistry and flow cytometry. RESULTS: Inoculation of apoptotic cells before EAT implantation stimulated tumour growth. This effect was reversed by in vivo pre-treatment with WEB2170. This treatment also reduced tumour growth and modified the microenvironment by reducing PGE2, VEGF and NO production. In B16F10 melanoma, WEB2170 alone or in association with DTIC significantly reduced tumour volume. Survival of the tumour-bearing mice was not affected by WEB2170 treatment but was significantly improved by the combination of DTIC with WEB2170. Tumour microenvironment elements were among the targets of the combination therapy since the relative frequency of COX-2 and galectin-3 positive cells and the microvascular density within the tumour mass were significantly reduced by treatment with WEB2170 or DTIC alone or in combination. Antibodies to PAF-R stained the cells from inside the tumour, but not the tumour cells grown in vitro. At the tissue level, a few cells (probably macrophages) stained positively with antibodies to PAF-R. CONCLUSIONS: We suggest that PAF-R-dependent pathways are activated during experimental tumour growth, modifying the microenvironment and the phenotype of the tumour macrophages in such a way as to favour tumour growth. Combination therapy with a PAF-R antagonist and a chemotherapeutic drug may represent a new and promising strategy for the treatment of some tumours.

Prion protein ablation increases cellular aggregation and embolization contributing to mechanisms of metastasis.

Cellular Prion Protein (PrP(C)) is a cell surface protein highly expressed in the nervous system, and to a lesser extent in other tissues. PrP(C) binds to the extracellular matrix laminin and vitronectin, to mediate cell adhesion and differentiation. Herein, we investigate how PrP(C) expression modulates the aggressiveness of transformed cells. Mesenchymal embryonic cells (MEC) from wild-type (Prnp(+/+)) and PrP(C)-null (Prnp(0/0)) mice were immortalized and transformed by co-expression of ras and myc. These cells presented similar growth rates and tumor formation in vivo. When injected in the tail vein, Prnp(0/0)ras/myc cells exhibited increased lung colonization compared with Prnp(+/+)ras/myc cells. Additionally, Prnp(0/0)ras/myc cells form more aggregates with blood components than Prnp(+/+)ras/myc cells, facilitating the arrest of Prnp(0/0)ras/myc cells in the lung vasculature. Integrin alpha(v)beta(3) is more expressed and activated in MEC and in transformed Prnp(0/0) cells than in the respective Prnp(+/+) cells. The blocking of integrin alpha(v)beta(3) by RGD peptide reduces lung colonization in transformed Prnp(0/0) cells to similar levels of those presented by transformed Prnp(+/+) cells. Our data indicate that PrP(C) negatively modulates the expression and activation of integrin alpha(v)beta(3) resulting in a more aggressive phenotype. These results indicate that PrP(C) may have main implications in modulating metastasis formation.

25(OH)D3 and 1,25(OH)2D3 serum concentration and breast tissue expression of 1alpha-hydroxylase, 24-hydroxylase and Vitamin D receptor in women with and without breast cancer.

1,25(OH)2D3 is an antiproliferative agent that may inhibit proliferation of breast cancer (BC) cells in vitro and BC development in animals. Epidemiological studies have shown a high incidence of BC in people less exposed to solar rays. To unravel the role of Vitamin D3 in BC patients, we have investigated serum levels of 25(OH)D3 and its active form 1,25(OH)2D3 as well as tissue expression of 1alpha-hydroxylase, 24-hydroxylase, and Vitamin D-receptor (VDR), determined by semiquantitative RT-PCR, in 88 Brazilian BC patients and 35 women without cancer (submitted to mammoplasties or resection of benign lesions). Median age of women with and without cancer was 51 and 46 years, respectively, and the majority of BC patients were classified as clinical stage II (67%). Although no differences in 25(OH)D3 serum concentration were found, 1,25(OH)2D3 (40+/-21 pg/ml) levels in BC patients were lower than in women without cancer (53+/-23). Our results indicate that 24-hydroxylase, VDR and 1alpha-hydroxylase mRNA tissue expression is similar in both groups and no correlation between 24-hydroxylase, 1alpha-hydroxylase, and VDR expression in breast tumors was found. A low 1,25(OH)2D3 serum concentration seems to be associated to breast cancer, however, the mechanism involved in this regulation is still unclear.

The expression of metaloproteinases-2 and -9 is different according to the patterns of growth and invasion in squamous cell carcinoma of the penis.

Squamous cell carcinoma (SCC) of the penis is characterized by different patterns of growth and local invasion. The matrix metalloproteinases (MMPs) is a family of proteolytic enzymes that are involved in the degradation of extracellular matrix to allow the migration of tumor cells. The present study examined whether the expression of MMP-2 and -9 is correlated with the patterns of tumor growth and invasion in penile SCC. The expression of MMP-2 and -9 was examined immunohistochemically in samples of 115 patients. The cases were divided in three groups according to the patterns of growth and invasion: group 1, exophytic growth and pushing pattern of invasion; group 2, endophytic growth and invasion in large sheets of cells; and group 3, endophytic growth and invasion in small group or isolated cells. Tumors with MMP-2 and -9 overexpression are deeply invasive and present an invasion pattern of small groups of cells. Also, expression of MMP-2 changed from membrane to cytoplasm in invasive tumors, maybe representing activation of MMP-2. These findings allow us to conclude that the less differentiated tumors, which are more invasive and with a pattern of invasion in small group of cells, are associated with the overexpression of MMPs.

Differential expression of apoptosis related proteins and nitric oxide synthases in Epstein Barr associated gastric carcinomas.

AIM: To determine the incidence of Epstein Barr virus associated gastric carcinoma (GC) in Brazil and compare the expressions of apoptosis related proteins and nitric oxide synthases between EBV positive and negative gastric carcinoma. METHODS: In situ hybridization of EBV-encoded small RNA-1 (EBER-1) and PCR was performed to identify the presence of EBV in GCs. Immunohistochemistry was used to identify expressions of bcl-2, bcl-xl, bak, bax, p53, NOS-1, NOS-2, and NOS-3 proteins in 25 EBV positive GCs and in 103 EBV negative GCS. RESULTS: 12% of the cases of GC (25/208) showed EBER-1 and EBNA-1 expression. The cases were preferentially of diffuse type with intense lymphoid infiltrate in the stroma. EBV associated GCs showed higher expression of bcl-2 protein and lower expression of bak protein than in EBV negative GCs. Indeed, expressions of NOS-1 and NOS-3 were frequently observed in EBV associated GCs. CONCLUSION: Our data suggest that EBV infection may protect tumor cells from apoptosis, giving them the capacity for permanent cell cycling and proliferation. In addition, EBV positive GCs show high expression of constitutive NOS that could influence tumor progression and aggressiveness.

Immunohistochemical assessment of mucosal cytokine profile in acetic acid experimental colitis.

UNLABELLED: Experimental colitis induced by acetic acid has been used extensively as a model for intestinal inflammatory disease. Colonic tissue lesions of intestinal inflammatory disease patients seem to be related to the increased local production of pro-inflammatory cytokines (IL-1, IL-6, TNF-alpha, and IFN-gamma). PURPOSE: To assess the cytokine expression pattern identified through immunohistochemistry in colonic mucosa after experimental colitis induced by acetic acid and establish the relationship between this pattern and the presence of macroscopic lesions. MATERIALS AND METHODS: Adult male Wistar rats (n = 39) were divided at random into 4 groups: NC45 and NC24 (control without colitis; sacrificed at 45 minutes and 24 hours, respectively); and WC45 and WC24 (with experimental colitis induced by acetic acid; sacrificed at 45 minutes and 24 hours, respectively). Macroscopic and microscopic alterations in colonic tissue were evaluated, and cytokine expression was assessed through immunohistochemistry. RESULTS: After 24 hours, IL-1 expression was greater in the groups with colitis when compared to the groups without colitis. IL-4 expression was higher in the WC45 group. There was an increase in both INF-gamma and IL-6 related to the presence of necrosis of the colonic mucosa in the groups with colitis for both periods evaluated. CONCLUSION: The immunohistochemical technique was efficient for the analysis of various cytokine expressions in the colonic tissue. There was an increase in the IL-1 pro-inflammatory cytokines as well as in IL-6 and IFN-gamma associated with the presence of colonic necrosis. Experimental colitis induced by acetic acid is a useful model for the development of studies assessing the role of cytokines in the inflammation of mucosa as well as anti-cytokine therapies.

Vitamin D3 modulation of plasminogen activator inhibitor type-1 in human breast carcinomas under organ culture.

Urokinase plasminogen activator (uPA), its cell-bound receptor (uPAR) and its main inhibitor plasminogen activator type 1 (PAI-1) are present primarily in stromal cells in invasive breast carcinoma. The purpose of this study was to investigate the regulation by 1,25 dihydroxyvitamin-D3 (VD3) of these invasion-associated markers expressed in breast cancer tumors under organ culture, which preserves the interacting network of tumor and stromal cells. Breast carcinoma slices (30 cases), obtained using the Krumdieck tissue slicer, cultured for 48 h in the presence or absence of 100 nM vitamin D3, were embedded in formalin-fixed paraffin. uPA, uPAR, PAI-1 and VD3 receptor (VDR) were analyzed by immunohistochemistry, and their expression, detected in tumor cells and fibroblasts of the specimens, was not statistically changed by culture conditions. The proportion of cases expressing uPA, uPAR and PAI-1 was not affected by VD3 in epithelial cells, but the fraction of cases displaying strong PAI-1 reactivity in fibroblasts was reduced ( P=0.016) compared with control slices. Fibroblasts isolated from invasive ductal carcinomas and from normal breast tissues expressed higher VDR mRNA levels than epithelial cells. In cultured tumor fibroblasts, PAI-1 immunostaining and mRNA levels were reduced by VD3-limiting fibroblast contribution to invasion.

[Cytokine participation in the acute rejection of intestinal transplantation in rats]. / Participação de citocinas na rejeição aguda do transplante intestinal em ratos.

BACKGROUND: Intestinal transplantation is a possible treatment for patients with short bowel syndrome, aiming the reintroduction of oral diet. However, the major obstacle in this procedure is the strong rejection. Delay in rejection diagnosis may be irreversible and lethal. AIM: To define method for early diagnosis of rejection based on the presence of interleucin-6 (IL-6) e interferon- gamma (IFN-gamma) from intestinal allograft. MATERIAL AND METHODS: Isogenic rats Brown-Norway (BN) and Lewis (LEW) were submitted to intestinal heterotopic allotransplantation and divided in two groups: LEW donor to LEW recipient isograft group (C) and BN donor to LEW recipient allograft group (Tx). According to the day of sacrifice, Tx group were subdivided in three subgroups with eight animals each as follow: Tx3--sacrificed at third postoperative day (POD), Tx5--sacrificed at fifth POD and Tx7--sacrificed at seventh POD. Eight animals from control group were subdivided in three moments according to the time of biopsy from the graft as follow: C3--biopsy at third POD; C5--biopsy at fifth POD and C7--biopsy at seventh POD. All animals from control group were sacrificed at seventh POD. Rejection parameters were compared between the control groups (C3 vs C5, C3 vs C7 and C5 vs C7, and allograft group (Tx3 vs Tx5, Tx3 vs Tx7 and Tx5 vs Tx7). The same parameters were analyzed between the control group and allograft groups (C3 vs Tx3, C5 vs Tx5 and C7 vs Tx7). RESULTS: In C group no statistical significant difference regarding the immunoexpression of the cytokines, while in Tx group, immunoexpression of IL-6 and IFN-gamma were remarkable since the fifth postoperative day.

Evaluation of prognostic factors in stage IIA breast tumors and their correlation with mortality risk.

UNLABELLED: Breast tumors exhibit extensive molecular and clinical heterogeneity. One of the most utilized breast carcinoma classifications is based on its molecular aspects and subdivides breast cancer into five major groups based on the expression of certain genes. In this study, we evaluated which factors are important in determining a prognosis after 5 years of follow-up for patients with clinical stage IIA breast tumors. We took into consideration the different phenotypes (luminal A luminal B HER-2 overexpression, basal and triple-negative), various epithelial-mesenchymal (EMT) molecular markers and adhesion molecules (E-cadherin, P-cadherin, N-cadherin, vimentin, twist snail and slug) and NOS-2, in addition to clinical and demographic data, tumor characteristics and treatment types. METHODS: The study population consisted of 82 patients with breast cancer. We analyzed eight molecular markers by immunohistochemistry on tissue microarrays containing breast tumor specimens from patients with ten years of follow-up, and we classified each tumor according to its estrogen receptor, progesterone receptor and HER-2 expression. We then placed the tumor into one of the above categories. RESULTS: The presence of several clinical and demographic factors, various histopathologies, treatment forms and several immunohistochemical markers were not associated with a worse prognosis for group IIA patients. The factors that were associated with a mortality risk were the triple-negative (odds ratio (OR) = 11.8, 95% confident interval (CI) = 2.0-70.3, P = 0.007) and basal (OR =18.4, 95% CI = 1.8-184.7, P= 0.013) phenotypic patterns. CONCLUSIONS: The EMT markers and NOS-2 were not mortality risk factors. Basal and triple-negative phenotypic patterns were related to a higher mortality risk in patients with stage IIA tumors.

Correlation Between Anthropometric Measures and Biomarker Changes After Neoadjuvant Therapy With Tamoxifen or Anastrozole in Postmenopausal Women With Breast Cancer.

BACKGROUND: Epidemiological studies have reported positive associations between anthropometric measures and risk for developing breast cancers that express hormone receptors and associated mortality. However, the impact of nutritional status on the molecular response to endocrine therapy has yet to be described. METHODS: Body mass index (BMI), waist circumference (WC), hip circumference (HP), and waist-to-hip ratio (WHR) were measured in patients with invasive ductal carcinoma (IDC) before and after neoadjuvant treatment with either tamoxifen or anastrozole, and a possible correlation with prognostic factors, as estrogen receptor (ER), progesterone receptor (PgR), and proliferative index (Ki-67), was analyzed. Fifty-seven patients with palpable ER-positive IDC were randomized into three neoadjuvant treatment groups and received anastrozole or placebo or tamoxifen for twenty-one days. Biomarker status was obtained by comparing the immunohistochemical evaluation of samples collected before and after treatment, using the Allred scoring system. Statistical analysis was performed using the Statistical Package for the Social Sciences (SPSS). RESULTS AND CONCLUSIONS: After treatment, the anastrozole group showed reduced ER and PgR expression (p < 0.05), and both the anastrozole and tamoxifen groups showed lower Ki-67 status. A significant reduction in PgR positivity (p < 0.05) was found in women with large WC and HC who were treated with anastrozole. Reduction in PgR positivity also tended to be associated with BMI (p = 0.09) in the anastrozole group. BMI, WC, HC and WHR correlated neither with biomarker levels in the tamoxifen and placebo groups nor with ER and Ki-67 status in the anastrozole group after primary endocrine treatment.

Evaluation of prognostic factors in stage IIA breast tumors and their correlation with mortality risk

Breast tumors exhibit extensive molecular and clinical heterogeneity. One of the most utilized breast carcinoma classifications is based on its molecular aspects and subdivides breast cancer into five major groups based on the expression of certain genes. In this study, we evaluated which factors are important in determining a prognosis after 5 years of follow-up for patients with clinical stage IIA breast tumors. We took into consideration the different phenotypes (luminal A luminal B HER-2 overexpression, basal and triple-negative), various epithelial-mesenchymal (EMT) molecular markers and adhesion molecules (E-cadherin, P-cadherin, N-cadherin, vimentin, twist snail and slug) and NOS-2, in addition to clinical and demographic data, tumor characteristics and treatment types. METHODS: The study population consisted of 82 patients with breast cancer. We analyzed eight molecular markers by immunohistochemistry on tissue microarrays containing breast tumor specimens from patients with ten years of follow-up, and we classified each tumor according to its estrogen receptor, progesterone receptor and HER-2 expression. We then placed the tumor into one of the above categories. RESULTS: The presence of several clinical and demographic factors, various histopathologies, treatment forms and several immunohistochemical markers were not associated with a worse prognosis for group IIA patients. The factors that were associated with a mortality risk were the triple-negative (odds ratio (OR) = 11.8, 95 percent confident interval (CI) = 2.0-70.3, P = 0.007) and basal (OR =18.4, 95 percent CI = 1.8-184.7, P= 0.013) phenotypic patterns. CONCLUSIONS: The EMT markers and NOS-2 were not mortality risk factors. Basal and triple-negative phenotypic patterns were related to a higher mortality risk in patients with stage IIA tumors.

Expressão do p53 no carcinoma epidermóide do lábio / P53 expression in squamous cell carcinoma of the lip

OBJETIVO: Verificar o valor da expressão do p53 no carcinoma epidermóide (CEC) de lábio. MÉTODO: O estudo imunohistoquímico foi feito em material fixo em formol e mantido em bloco de parafina, corado com anticorpos anti-p53, segundo técnica da Streptavidina-Biotina-Peroxidase. Para análise estatística, foi empregado o teste de Fisher para a diferenciação de grupos em relação às variáveis do estudo. RESULTADOS: A expressão do p53 foi positiva em 87,5 por cento do CEC bem diferenciado, 60 por cento no moderadamente diferenciado e 91,67 por cento no pouco diferenciado. Nas margens de ressecção cirúrgica foi negativa em 94,23 por cento e positiva em 5,77 por cento, havendo associação entre o grau de diferenciação e a expressão do p53 (p=0,05). CONCLUSÃO: A expressão do p53 foi positiva na lesão primária e negativa na margem de ressecção cirúrgica, mas não é determinante de mudanças no paradigma cirúrgico.

BACKGROUND: To assess the p53 expression in squamous cell carcinoma (SCC) of the lip. METHODS: Immunohystochemical study for samples fixed in formaline and paraphin in bloc stained with anti-p53 antibodies through Streptavidina-Biotina-Peroxidase. For statistical analysis the Fisher Test was employed for group differences (p<0.10). RESULTS: The p53 expression were positive in 87.50 percent of well differentiated SCC, 60.0 percent of moderately differentiated tumors, 91.67 percent of poorly differentiated; for surgical margins, 94.23 percent were negative and 5.77 percent positive, with an association between differentiation degree and p53 expression (p=0.05). CONCLUSION: The p53 expression was significant in SCC of the lip and negative for surgical margins, but it is not determinant of changing in surgical paradigm.

E-cadherin/beta-catenin expression pattern, clinicopathological parameters and prognosis in gastric carcinomas

Objectives: This study aimed to evaluate the expression pattern of some markers (E-cadherin and â-catenin) related to cellular adhesion and their relationship with histological tumor type according to Laurén’s system, clinicopathological features and patient survival. Material and Methods: We did immunohistochemical analysis in a retrospective series of 446 gastric carcinomas using tissue microarray method (TMA). Clinicopathological features and overall survival data of all patients were retrospectively reviewed from hospital records. For all statistical analyses, p<0.05 was considered significant. Results: The reduced/absent expression of E-cadherin occurred more frequently in diffuse than intestinal type tumors and it was correlated with worse biological behavior and poor prognosis for patients with diffuse type gastric carcinomas. The pattern of â-catenin expression was closely related to histological type and E-cadherin expression. Although patients with nuclear/absent â-catenin immunoreactivity showed worse survival index, no statistical correlation was found with overall survival. In multivariated analysis, only pTNM staging system persisted as independent prognostic marker. Conclusion: In the present study, alterations in E-cadherin/â-catenin complex expression showed significant correlations with clinicopathological parameters, as well as its implications for tumor progression and prognosis in gastric cancer. Our results indicate that markers expression pattern may be a useful marker of differentiation and suggest further investigations of their prognostic relevance to specific histological groups.

Expressão imuno - histoquímica de c - erb - B2 e p53 em carcinomas gástricos / Imunohistochemical expression of c - erb - B2 and p53 in gastric carcinomas

INTRODUÇAO: Em nosso meio, os carcinomas gástricos ainda são neoplasias bastante freqüentes e responsáveis por altas taxas de mortalidade. Recentemente, têm-se demonstrado a expressão de p53 e a amplificacão do gene c-erb-B2 nos carcinomas gástricos. A relevância e o significado biológico destas alteracões ainda não foram totalmente estabelecidos. OBJETIVO: Estudar as expressões imuno-histoquímicas de p53 e c-erb-B2 em 482 casos de carcinomas gástricos. MATERIAL E MÉTODOS: Foram construídos três blocos de tissue microarray (TMA) utilizando-se duplicatas de 482 casos de carcinomas gástricos. Os cortes foram corados por hematoxilina e eosina (HE), tendo sido feita pesquisa para p53 e c-erb-B2. Foram considerados positivos para p53 os casos com marcacão nuclear em mais de 10 por cento das células tumorais. Para o c-erb-B2 foram considerados positivos os casos com marcacão de membrana completa em mais de 10 por cento das células tumorais. RESULTADOS: A expressão de p53 e c-erb-B2 foi observada em 30 por cento e 12 por cento dos casos, respectivamente. Em relacão aos tipos histológicos observou-se correlacão entre os carcinomas do tipo intestinal e a expressão de c-erb-B2 (p < 0,001). A expressão de p53 foi mais freqüente nos carcinomas com mais de 5cm de diâmetro (p = 0,036). Não foram observadas alteracões nas curvas de sobrevida dos pacientes em relacão às expressões desses marcadores. CONCLUSAO: Em nosso meio, carcinomas gástricos do tipo intestinal são mais freqüentemente positivos para c-erb-B2 nos tipos intestinais do que nos difusos. A expressão de p53 está associada ao tamanho tumoral. A técnica do TMA é válida e eficiente para o estudo de marcadores imuno-histoquímicos, com forte correlacão com os cortes tradicionais de representacão do tumor.

Immunohistochemical assessment of mucosal cytokine profile in acetic acid experimental colitis

O modelo de colite experimental induzida por ácido acético (CEAA) vem sendo extensamente utilizado em estudos sobre doenças inflamatórias intestinais (DII). Lesões no tecido colônico em portadores de DII parecem estar relacionados à produção local aumentada de citocinas pró-inflamatórias (IL-1, IL-6, TNF-a e IFN-g). OBJETIVO: Avaliar o padrão de expressão de citocinas identificadas por imunohistoquímica em tecido colônico após CEAA e relacioná-lo à presença de lesões macroscópicas. MATERIAL E MÉTODOS: Ratos machos Wistar adultos (n=39) foram submetidos ou não à CEAA e sacrificados para retirada do tecido colônico em dois períodos distintos, perfazendo 4 grupos aleatórios: SC45 e SC24 (sem colite; sacrifício 45 minutos e 24 horas, respectivamente); CC45 e CC24 (com colite; sacrifício 45 minutos e 24 horas, respectivamente). Avaliaram-se alterações macro e microscópicas do cólon e sua expressão de citocinas foi avaliada por imunohistoquímica. RESULTADOS: Após 24 horas, a expressão de IL-1 foi maior no grupo com colite, em relação ao sem colite. IL-4 foi mais expressa no grupo CC45. Houve aumento de INF-g e IL-6, relacionados à presença de necrose da mucosa colônica, nos grupos com colite, em ambos os períodos avaliados. CONCLUSÃO: A técnica de imunohistoquímica foi eficiente para a análise da expressão de citocinas na mucosa colônica. Houve aumento da expressão das citocinas pró-inflamatórias IL-1 e de IL-6 e IFN-g associado à presença de necrose colônica. A CEAA é um bom modelo para o desenvolvimento de estudos destinados a avaliar o papel das citocinas na inflamação da mucosa e terapias anti-citocinas.

Análise imuno-histoquímica das sintases do óxido nítrico em adenocarcinomas gástricos / Immunohistochemical expression of nitric oxide synthases in gastric adenocarcinomas

INTRODUÇAO: O óxido nítrico (NO) é uma molécula mediadora de diversas funções, tais como vasodilatação, neurotransmissão e metabolismo do ferro. Os efeitos do NO na biologia tumoral são ambíguos e complexos. A atividade das sintases do óxido nítrico (NOS) tem sido demonstrada em diversos tumores humanos. OBJETIVO: Pesquisar a expressão das isoformas das NOS em carcinomas gástricos e correlacionar estes achados com características demográficas e histopatológicas destes tumores. MATERIAL E MÉTODOS: O estudo imuno-histoquímico das NOS (NOS-1, NOS-2 e NOS-3) foi realizado em 128 casos de carcinomas gástricos classificados de acordo com o sistema de Lauren. RESULTADOS: A positividade para NOS-1 foi detectada em 92/128 (70 por cento) dos casos, para NOS-2 em 36/128 (30 por cento) e para NOS-3 em 54/128 (42 por cento) dos casos. Na análise estatística observou-se correlação com o tipo intestinal e expressão de NOS-3, e tumores avançados mostraram maior expressão de NOS-2. CONCLUSAO: Os carcinomas gástricos mostram expressão das três isoformas de NOS, sendo as NOS constitutivas presentes em maior número de casos. A freqüente expressão de NOS induzida nos carcinomas gástricos avançados sugere uma participação de NOS na progressão e na disseminação tumoral na mucosa gástrica.

P53 overexpression in epidermoid carcinoma of the head and neck

The theory of field cancerization in tumors of the head and neck reflects the complex oncogenesis that occurs in this region. The mechanisms that control cell proliferation at the molecular level in epidermoid carcinomas (ECs) of the upper aerodigestive tract are still unclear. Mutations in p53 are the genetic alterations most often detected in ECs of the head and neck and seem to contribute actively to the carcinogenic process triggered by p53 as a tumor-suppressor gene and to its association with tobacco. The objective of the present study was to investigate the expression of p53 protein in epidermoid head and neck carcinomas by immunohistochemistry and its immunohistochemical correlation with other prognostic factors. The study was conducted on 63 consecutive ECs cases not submitted to previous treatment. Specimens of the tumor and of the normal adjacent mucosa were collected during surgery and submitted to immunohistochemical reaction for the determination of the expression of anti-protein p53 antibody (M7001 DAKO A/S, Denmark). Anatomo-clinical and demographic data were not significantly correlated with the presence of lymph node metastases or p53 expression in the tumor or in the adjacent normal mucosa. Tumor localization in the larynx was significantly correlated with p53 expression. Histological grading as grades I,II,III and IV was correlated whith significant p53 expression (p = 0.025). Conclusions: 1) in the studied material obtained from 63 cases of head and neck ECs, we detected a 48 percent rate of immunohistochemically detectable p53 overexpression; 2) we did not detect a relationship between demographic patient data and p53 expression in the tumor or in the normal adjacent mucosa; 3) p53 overexpression was significantly more frequent in ECs material from the larynx; and 4) The presence of 12 cases with p53 overexpression in the normal adjacent mucosa and with a p53-negative tumor is in agreement with the theory of field concerization. Follow-up of this patient series for a longer period of time will permit a better analysis of these values.