979 resultados para Eyelid tumors
Resumo:
Gene silencing may occur in breast cancer samples from patients presenting with occult metastatic cells in the bone marrow and one mechanism regulating gene suppression is heterochromatin formation. We have studied whether members of the heterochromatin protein 1 family Hp1(Hs alpha), Hp1(Hs beta) and Hp1(Hs gamma) which take part in chromatin packaging and gene expression regulation, were differentially expressed in tumors from patients with and without occult metastatic cells in their bone marrow. Tumor samples and bone marrow aspirates were obtained from 37 breast cancer patients. Median age was 63 years and 68% of the patients presented with clinical stage I/II disease. Presence of occult metastatic cells in bone marrow was detected through keratin-19 expression by nested RT-PCR in samples from 20 patients (54.1%). The presence of occult metastatic cells in bone marrow was not associated with node involvement, histological grade, estrogen receptor and ERBB2 immunoexpression. Relative gene expression of HP1(Hs alpha), HP1(Hs beta) and HP1(Hs gamma) was determined by real-time RT-PCR and did not vary according to the presence of occult metastatic cells in bone marrow. In addition, the combined expression of these three transcripts could not be used to classify samples according to the presence of bone marrow micrometastasis. Our work indicates that regulation of heterochromatin formation through HP1 family members may not be the sole mechanism implicated in the metastatic process to the bone marrow. (Int J Biol Markers 2008; 23: 219-24)
Resumo:
The E7 transforming protein of Human Papillomavirus type 16 (HPV16) is expressed in the skin of a line of RIB mice transgenic for the E6 and E7 open reading frames of HPV16 driven from the alpha A crystallin promoter (FVB alpha AcryHPV16E6E7). We have transferred skin from FVB alpha AcryHPV16E6E7 mice to naive or E7-primed syngeneic NE recipients to assess whether the E7 protein of HPV16 can function as a minor transplantation antigen (MTA) and promote skin graft rejection. FVB mice did not reject E7 expressing tail or flank skin grafts. E7 immunized FVB x C57BL/6J mice recipients of FVB alpha AcryHPV16E6E7 x C57BL/6J skin generated humoral and DTH responses to E7 in vivo and E7-specific CTL precursors in the spleen, but failed to reject 57 expressing tail skin grafts by 100 days posttransfer. Thus although HPV16 E7 + ve mesenchymal and endodermal tumors can be eliminated by an E7-specific immune response, the same protein is unable to act as a MTA and promote graft rejection when expressed in skin cells. Lack of rejection of grafts expressing MTAs such as E7 may be relevant to the immunology of epithelial tumors expressing tumor-specific antigens and to our understanding of the immunology of diseases of the skin. (C) 1997 Academic Press.
Resumo:
In previous studies, we determined that beta 1 integrins from human colon tumors have elevated levels of alpha 2-6 sialylation, a modification added by beta-galactosamide alpha-2,6-sialyltranferase I (ST6Gal-I). Intriguingly, the beta 1 integrin is thought to be a ligand for galectin-3 (gal-3), a tumor-associated lectin. The effects of gal-3 are complex; intracellular forms typically protect cells against apoptosis through carbohydrate-independent mechanisms, whereas secreted forms bind to cell surface oligosaccharides and induce apoptosis. In the current study, we tested whether alpha 2-6 sialylation of the beta 1 integrin modulates binding to extracellular gal-3. Herein we report that SW48 colonocytes lacking alpha 2-6 sialylation exhibit beta 1 integrin-dependent binding to gal-3-coated tissue culture plates; however, binding is attenuated upon forced expression of ST6Gal-I. Removal of alpha 2-6 sialic acids from ST6Gal-I expressors by neuraminidase treatment restores gal-3 binding. Additionally, using a blot overlay approach, we determined that gal-3 binds directly and preferentially to unsialylated, as compared with alpha 2-6-sialylated, beta 1 integrins. To understand the physiologic consequences of gal-3 binding, cells were treated with gal-3 and monitored for apoptosis. Galectin-3 was found to induce apoptosis in parental SW48 colonocytes ( unsialylated), whereas ST6Gal-I expressors were protected. Importantly, gal-3-induced apoptosis was inhibited by function blocking antibodies against the beta 1 subunit, suggesting that beta 1 integrins are critical transducers of gal-3-mediated effects on cell survival. Collectively, our results suggest that the coordinate up-regulation of gal-3 and ST6Gal-I, a feature that is characteristic of colon carcinoma, may confer tumor cells with a selective advantage by providing a mechanism for blockade of the pro-apoptotic effects of secreted gal-3.
Resumo:
Previously we found that levels of LRRC49 (leucine rich repeat containing 49; FLJ20156) transcripts were elevated in ER-positive breast tumors compared with ER-negative breast tumors. The LRRC49 gene is located on chromosome 15q23 in close proximity to the THAP10 (THAP domain containing 10) gene. These two genes have a bidirectional organization being arranged head-to-head on opposite strands, possibly sharing the same promoter region. Analysis of the promoter region of this gene pair revealed the presence of potential estrogen response elements (EREs), suggesting the potential of this promoter to be under the control of estrogen. We used quantitative real-time PCR (qPCR) to evaluate the expression of LRRC49 and THAP10 in a series of 72 primary breast tumors, and found reduced LRRC49 and THAP10 expression in 61 and 46% of the primary breast tumors analyzed, respectively. In addition, the occurrence of LRRC49/THAP10 promoter hypermethylation was examined by methylation specific PCR (MSP) in a sub-group of the breast tumors. Hypermethylation was observed in 57.5% of the breast tumors analyzed, and the levels of mRNA expression of both genes were inversely correlated with promoter hypermethylation. We investigated the effects of 17 beta-estradiol on LRRC49 and THAP10 expression in MCF-7 breast cancer cells and found both transcripts to be up-regulated 2- to 3-fold upon 17 beta-estradiol treatment. Our results show that the transcripts of LRRC49/THAP10 bidirectional gene pair are co-regulated by estrogen and that hypermethylation of the bidirectional promoter region simultaneously silences both genes. Further studies will be necessary to elucidate the role of LRRC49/THAP10 down-regulation in breast cancer.
Resumo:
Background Acral lentiginous melanoma (ALM) is a clinicopathologic subtype of cutaneous malignant melanoma. ALM is the most common type of melanoma amongst Asians, Africans, and patients with mixed ancestry. In Brazil, ALM comprises 10% of cutaneous melanoma. ALM develops on palmar, plantar, and subungual skin, and its biology is different from that of other cutaneous melanomas, where sunlight is the major known environmental determinant. Alterations and inactivation of the p16INK4 gene that encodes a specific inhibitor of cyclin-dependent kinase have been related to melanoma genesis and progression. Few studies, however, have addressed p16 expression in ALM. Methods In order to verify and compare p16 protein expression, 32 paraffin-embedded ALM specimens were subjected to a immunohistochemical technique using a monoclonal anti-p16 antibody. The tumors were classified according to thickness (up to 1.0 mm and thicker than 1.0 mm) and the presence of ulceration. Results Twenty-five (78%) ALMs displayed positive p16 protein expression: 21 of the 25 (84%) with a thickness of more than 1.0 mm, and four of the seven (57%) with a thickness of 1.0 mm or less. Thirteen of the 17 (76%) nonulcerated lesions and 12 of the 15 (80%) ulcerated lesions displayed positive p16 protein expression. Conclusion The data obtained suggest that p16 protein expression per se may not represent a marker of retinoblastoma protein (pRb) pathway disturbance in ALM tumorigenesis.
Resumo:
Background Molluscum contagiosum (MC) is a Molluscipox virus infection of keratinocytes with hyperplasia and intracytoplasmic inclusions-the molluscum bodies (MBs). Few papers address cytokeratins (K) profile in MC, mainly focusing terminal keratinization process. Methods Forty-one MC lesions were subjected to immunohistochemical technique to verify K1, K10, K14, K16, involucrin, filaggrin, E-cadherin and p63 expression. MC immunolabeling pattern was compared to adjacent normal appearing epidermis (ANAE). Results In MC and ANAE, K1/K10 were expressed in suprabasal layers, K14 was expressed in basal and suprabasal layers and K16 was expressed through all spinous layer. Involucrin and filaggrin were observed in granular, spinous and in basal layer of ANAE and MC. E-cadherin was present up to the first layers of MC while ANAE exhibited E-cadherin labeling at basal and spinous layers. Basal and spinous layers keratinocytes nuclei, in both MC and ANAE, express p63. Conclusion Infection by Molluscipox virus alters keratinocyte differentiation status. The presence of K14 and p63 in spinous layer, as well as early expression of involucrin and filaggrin, associated to a hyperproliferative state disclosed by K16 expression, may be a result of disruption in keratinocytes maturation process. The changes observed at ANAE may represent early events in keratinization disturbance. Callegaro CF, Sotto MN. Molluscum contagiosum: immunomorphological aspects of keratinocytes markers of differentiation and adhesion.
Resumo:
Background: Epidermodysplasia verruciformis (EV) is a rare genodermatosis with susceptibility to human papillomavirus (HPV) infection, and high risk of skin cancer considered a model of viral oncogenesis. Methods: Fifteen cases of EV plane wart (PW)-type lesions (EV) and 14 cases of PW in healthy individuals were subjected to immunohistochemical technique for cytokeratins (K) 1, 10, 14, 16, 4, involucrin, filaggrin and e-cadherin. Results: K1/10 showed retarded or negative expression in EV, being substituted by K14. Expression of K14 occurred in the basal and suprabasal layers in both groups, but in EV, its expression was observed up to the more superficial layers. Both groups showed positivity for K16 and K4, involucrin expression in lower levels of the spinous layer and unaltered filaggrin expression. E-cadherin expression was diminished at the koilocytotic foci of both lesions, more superficially in EV. Conclusion: Infection by HPV may alter the differentiation status of the epidermis, leading to a major expression of K14, delayed or absent expression of K1/10 and earlier involucrin expression, especially in EV. It also stimulates the expression of K16 and K4. Filaggrin expression is not altered, and e-cadherin is diminished in superficial koilocytotic cells` foci in EV.
Resumo:
BACKGROUND - Squamous cell carcinomas of the skin of the bead are better treated with Mobs micrographic surgery which has the lowest recurrence rates and allows spare normal tissue. There are some characteristics of squamous cell carcinoma that can be related to a higher number of surgical stages. OBJECTIVE - To study characteristic of head squamous cell carcinoma that predicts a higher number of Mohs surgical stages. METHODS - A retrospective analysis of 51 squamous cell carcinomas of the bead treated with Mobs surgery was performed to determine risk factors for a higher number of surgical stages. The characteristics analyzed were clinical limits, morphology, recurrence, histological differentiation and size and compared to the number of surgical stages. The analysis was performed by Fisher`s exact test and multivariate logistic regression. RESULTS - The recurrent squamous cell carcinomas showed a tendency for a higher number of stages (p=0,081). The Odds Ratio for a higher number of Mobs stages was three for inaccurate limits; although not statistically significant, it corroborates clinical and previous publication. CONCLUSION - Clinical characteristics of squamous cell carcinoma as recurrence and inaccurate limits would not predict, but could indicate tendency of a higher number of Mobs micrographic surgery stages.
Resumo:
This study describes a simple method for long-term establishment of human ovarian tumor lines and prediction of T-cell epitopes that could be potentially useful in the generation of tumor-specific cytotoxic T lymphocytes (CTLs), Nine ovarian tumor lines (INT.Ov) were generated from solid primary or metastatic tumors as well as from ascitic fluid, Notably all lines expressed HLA class I, intercellular adhesion molecule-1 (ICAM-1), polymorphic epithelial mucin (PEM) and cytokeratin (CK), but not HLA class II, B7.1 (CD80) or BAGE, While of the 9 lines tested 4 (INT.Ov1, 2, 5 and 6) expressed the folate receptor (FR-alpha) and 6 (INT.Ov1, 2, 5, 6, 7 and 9) expressed the epidermal growth factor receptor (EGFR); MAGE-1 and p185(HER-2/neu) were only found in 2 lines (INT.Ov1 and 2) and GAGE-1 expression in 1 line (INT.Ov2). The identification of class I MHC ligands and T-cell epitopes within protein antigens was achieved by applying several theoretical methods including: 1) similarity or homology searches to MHCPEP; 2) BIMAS and 3) artificial neural network-based predictions of proteins MACE, GAGE, EGFR, p185(HER-2/neu) and FR-alpha expressed in INT.Ov lines, Because of the high frequency of expression of some of these proteins in ovarian cancer and the ability to determine HLA binding peptides efficiently, it is expected that after appropriate screening, a large cohort of ovarian cancer patients may become candidates to receive peptide based vaccines. (C) 1997 Wiley-Liss, Inc.
Resumo:
Background Familial adenomatous polyposis is a genetic syndrome associated with an increased risk of colorectal cancer (CRC) and different extracolonic manifestations Goals The goal of this study is to evaluate the frequency of death causes Material and Methods Charts from 97 patients treated from 1977 to 2008 were reviewed Retrieved data and family information allowed us to classify causes of death in those related to CCR to other malignancies or other causes Results There were analyzed data from 46 men (47 4%) and 51 women (52 6%) with an average age of 35 1 years (14 to 82) At diagnosis, 57 patients (58 7%) already had CRC-associated polyposis There were performed 93 colectomies, one internal diversion, and one partial resection Two patients were not operated on Results from 19 deceased patients (19 5%) were analyzed CRC, other tumors (desmoid tumors, lymphoma, and gastric cancer), and other causes (complication of duodenal cancer surgery, complication after ileorectal anastomosis (IRA), and coronary disease) were responsible for 12 (63 1%), four (21 1%), and three (15 8%) of all deaths, respectively Death from CRC occurred in the context of either systemic, rectal, or pouch recurrence Desmoid disease was the second cause of death (10 5% of all causes), leading to a fatal outcome 22% of all patients who developed DT during the study period Upper digestive carcinomas were responsible for other two death cases Conclusions (1) CRC is still the most prevalent cause of death, (2) even after curative resections, CRC can cause death through rectal or pouch malignization, (3) long-term survival was also strongly related to the development of extracolonic neoplasia, especially desmoid tumors and gastroduodenal carcinoma, (4) our results raise the need for local improvement in familiar screening and help us to define follow-up strategies and patient-information standards
Resumo:
Collision tumors consist of two independent but coexisting tumors. This uncommon situation might be easily mistaken for a composite tumor where one histogenetic event originates from two apparently distinct neoplasms. Colorectal collisions are particularly unusual; here, we report the exceedingly rare case of a 61-year-old man with malignant melanoma and adenocarcinoma colliding in the rectum. Collision tumors have an idiopathic pathophysiology and in fact ""accidental meeting"" is accepted by many authors. This article discusses the concepts about cancer development, which are overlooked by this hypothesis, another theory to explain that this rare occurrence involves microenvironment changes.
Resumo:
Lineage-survival oncogenes are activated by somatic DNA alterations in cancers arising from the cell lineages in which these genes play a role in normal development(1,2). Here we show that a peak of genomic amplification on chromosome 3q26.33 found in squamous cell carcinomas (SCCs) of the lung and esophagus contains the transcription factor gene SOX2, which is mutated in hereditary human esophageal malformations(3), is necessary for normal esophageal squamous development(4), promotes differentiation and proliferation of basal tracheal cells(5) and cooperates in induction of pluripotent stem cells(6-8). SOX2 expression is required for proliferation and anchorage-independent growth of lung and esophageal cell lines, as shown by RNA interference experiments. Furthermore, ectopic expression of SOX2 here cooperated with FOXE1 or FGFR2 to transform immortalized tracheobronchial epithelial cells. SOX2-driven tumors show expression of markers of both squamous differentiation and pluripotency. These characteristics identify SOX2 as a lineage-survival oncogene in lung and esophageal SCC.
Resumo:
Background: Malignancies of the biliary and pancreatic systems are associated with a poor prognosis. However, ampullary cancer carries a better prognosis and is often diagnosed when curative treatment is still possible. Accurate staging is important for the determination of the most appropriate treatment option. Objectives: (1) To determine the test performance characteristics of EUS and CT in loco-regional staging of ampullary neoplasms, and (2) to determine the impact of CT scan results on the test performance characteristics of EUS. Design and Setting: Prospective single-arm intervention study performed in 2 academic hospitals. Results and Main Outcome Measurements: Thirty-seven patients were screened and 33 staged with EUS and CT A total of 27 patients (13 men; mean age, 69.5 years; mean serum bilirubin level, 12.6 mg/dL) with locally advanced disease completed the protocol with EUS and CT and underwent surgical resection. Tumor classifications were as follows: 2 patients (7.4%), T1 tumors; 13 patients (48.1%), T2 tumors; and 12 patients (44.4%), T3 tumors, as per surgical pathology. Seventeen tumors (62.9%) were classified as NO and 10 (37.1%) as NI. The difference in proportion of correct tumor (74.1% vs 51.8%; P =.15, 95% CI, -0.06-0-50) and lymph node (81.4% vs; 55.5%; P =.07, 95% Cl, -0.01-0.53) staging by EUS and CT, respectively, was not statistically significantly different. However, the strength of tumor (kappa 0.51 vs 0.11) and nodal (kappa 0.59 vs 0.05) agreement with pathology was statistically significantly higher for EUS than for CT (P <.05). EUS was more sensitive and specific than CT for tumor and nodal staging, and the association of CT to EUS data did not improve the final test accuracy Limitation: Low number of T1 tumors. Conclusions: EUS is in accurate diagnostic test and exhibits a high level of agreement with surgical pathology. CT findings do not improve the test performance characteristics of EUS. Therefore, the evaluation for metastatic disease should not be compromised by CT protocols that aim to perform tumor and nodal staging. Further studies to determine the role of specialized CT protocols in patients with ampullary malignancies are needed. (Gastrointest Endosc 2009;70:290-6.)
Resumo:
OBJECTIVES: Local excision is currently being considered as an alternative strategy for ypT0-2 rectal cancer. However, patient selection is crucial to rule out nodal disease and is performed by radiologic studies that consider size as a surrogate marker for positive nodes. The purpose of this study was to determine the difference in size between metastatic and nonmetastatic nodes and the critical lymph node size after neoadjuvant chemoradiation therapy. METHODS: The 201 lymph nodes available from 31 patients with ypT0-2 rectal cancer were reviewed and measured. Lymph nodes were compared according to the presence of metastases and size. RESULTS: There was a mean of 6.5 lymph nodes per patient and 12 positive nodes of the 201 recovered (6%). Ninety-five percent of all lymph nodes were <5 mm, whereas 50% of positive lymph nodes were <3 mm. Metastatic lymph nodes were significantly greater in size (5.0 vs. 2.5mm; P = 0.02). Lymph nodes >4.5 mm had a greater risk of harboring metastases (P = 0.009). CONCLUSIONS: Patients with ypT0-2 rectal cancer following neoadjuvant chemoradiation have very small perirectal nodes. Individual metastatic lymph nodes are significantly larger. However, a significant number of lymph nodes after neoadjuvant chemoradiation (negative and positive) are <3 mm. Individual lymph node size is not a good predictor of nodal metastases and may lead to inaccurate radiologic staging.
Resumo:
Background Mucinous component is associated with distinct clinical and pathological features and poor survival in colorectal cancer. The purpose of this study was to determine differences in outcomes of patients with mucinous colorectal adenocarcinoma according to the type of mucin expressed. Materials and Methods Immunohistochemistry was performed in all tumors of patients who underwent radical surgery between 1998 and 2003 with mucinous colorectal cancer using antibodies against MUC1, 2, and 5. Correlation between immunoexpression and clinical, pathological features and survival was performed. Results Of the 418 patients treated in this period, only 35 had a mucinous adenocarcinoma. Of these, 25 were positive for 1 or more mucin expression. MUC2 expression correlated with tumor site and depth of penetration, while MUC5 expression correlated to tumor site. Overall survival was significantly worse for patients with MUC2 expression, and disease-free survival was significantly worse for patients with MUC1 expression. Conclusions Mucin expression may have significant correlation to specific clinical-pathological features and survival of patients with mucinous-type colorectal adenocarcinoma. These differences may reflect distinct molecular mechanisms involved in carcinogenesis of mucinous colorectal adenocarcinoma.