957 resultados para Perineural invasion


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TMPRSS2–ERG is the most frequent type of genomic rearrangement present in prostate tumors, in which the 5- prime region of the TMPRSS2 gene is fused to the ERG oncogene. TMPRSS2, containing androgen response elements (AREs), is regulated by androgens in the prostate. The truncated TMPRSS2-ERG fusion transcript is overexpressed in half of the prostate cancer patients. The formation of TMPRSS2-ERG transcript is an early event in prostate carcinogenesis and previous in vivo and in vitro studies have shown ectopic ERG expression to be associated with increased cell invasion. However, the molecular function of ERG and its role in cell signaling is poorly understood. In this study, genomic rearrangement of ERG with TMPRSS2 was studied by using comparative genomic hybridization (CGH) in prostate cancer samples. The biological processes associated with the ERG oncogene expression in prostate epithelial cells were studied, and the results were compared with findings observed in clinical prostate tumor samples. The gene expression data indicated that increased WNT signaling and loss of cell adhesion were a characteristic of TMPRSS2- ERG fusion positive prostate tumor samples. Up- regulation of WNT pathway genes were present in ERG positive prostate tumors, with frizzled receptor 4 (FZD4) presenting with the highest association with ERG overexpression, as verified by quantitative reverse transcription-PCR, immunostaining, and immunoblotting in TMPRSS2-ERG positive VCaP prostate cancer cells. Furthermore, ERG and FZD4 silencing increased cell adhesion by inducing active β1-integrin and E-cadherin expression in VCaP cells. Furthermore, we found a novel inhibitor, 4-(chloromethyl) benzoyl chloride which inhibited the WNT signaling and induced similar phenotypic effects as observed after ERG or FZD4 down regulation in VCaP cells. In conclusion, this work deepens our understanding on the complex oncogenic mechanisms of ERG in prostate cancer that may help in developing drugs against TMPRSS2-ERG positive tumors.

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Incidence of nonmelanoma skin cancer (NMSC) is increasing. Ultraviolet (UV) –light is a major risk factor for the development of cutaneous SCC. Cutaneous SCCs that develop to chronic ulcers are known to progress and metastasize more easily than UV-induced SCCs. Matrix metalloproteinases (MMPs) are a group of proteolytic enzymes which are suggested to have a role in cancer growth and invasion. The molecular background for progression of cutaneous SCC was examined by immunohistochemistry (IHC) using tissue samples of recessive dystrophic epidermolysis bullosa (RDEB) –associated SCC, sporadic UV-induced SCC, and SCC precursors. IHC studies using tissue microarray (TMA) technique revealed overexpression of MMP-7 and MMP-13 in SCC tumor cells. MMP-7 expression was enhanced especially in the SCC tumor cells of the RDEB –associated SCCs. Studies with SCC cell lines showed that tumor cell derived MMP-7 activated heparin binding epidermal growth factor –like growth factor (HB-EGF) which enhanced the growth of SCC tumor cells. Further, it was shown that type VII collagen (COL7) is expressed in sporadic SCC tumor cells. Interestingly, it was shown that SCC –associated MMP-13 is capable of cleaving COL7 in vitro. COL7 cleavage may have a role in the progression of cutaneous SCC. Studies on serine proteinase inhibitor gene family using SCC tumor cell gene array, quantitative real-time PCR, SCC cell lines, normal human epidermal keratinocytes and IHC of TMA samples showed that serine proteinase inhibitor clade A, member 1 (serpinA1, alpha-1-antitrypsin) is expressed and produced by human SCC tumor cells but not by normal keratinocytes. Moreover, serpinA1 expression was shown to correlate with the progression of cutaneous SCC using transformed HaCaT-cell lines and mouse chemically induced skin SCC model. SerpinA1 may serve as a novel biomarker for the progression of cutaneous SCC. This study elucidated putative mechanisms of the progression of cutaneous SCC and revealed novel biomarker candidates for the progression of SCC of the skin.

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Matrix metalloproteinase-13 (MMP-13) is a potent proteolytic enzyme, whose expression has been previously associated with fetal bone development and postnatal bone remodeling and with adult gingival wound healing. MMP-13 is also known to be involved in the growth and invasion of various cancers including squamous cell carcinoma (SCC) of the skin. The aim of this study was to further elucidate the function and regulation of MMP-13 in wound repair and cancer. In this study, it was shown that fetal skin fibroblasts express MMP-13 in response to transforming growth factor-β in a p38 MAP kinase dependent manner. In addition, MMP-13 was found to be expressed in vivo by wound fibroblasts in human fetal skin grafted on SCID mice. Adenovirally delivered expression of MMP-13 enhanced collagen matrix contraction by fibroblasts in vitro in association with altered cytoskeletal structure, enhanced proliferation and survival. These results indicate that MMP-13 is involved in cell-mediated collagen matrix remodeling and suggest a role for MMP-13 in superior matrix remodeling and scarless healing of fetal skin wounds. Using an MMP-13 deficient mouse strain, it was shown that MMP-13 is essential for the normal development of experimental granulation tissue in mice. MMP-13 was implicated in the regulation of myofibroblast function and angiogenesis and the expression of genes involved in cellular proliferation and movement, immune response, angiogenesis and proteolysis. Finally, epidermal mitogen, keratinocyte growth factor (KGF) was shown to suppress the malignant properties of skin SCC cells by downregulating the expression of several target genes with potential cancer promoting properties, including MMP-13, and by reducing SCC cell invasion. These results provide evidence that MMP-13 potently regulates cell viability, myofibroblast function and angiogenesis associated with wound healing and cancer. In addition, fibroblasts expressing MMP-13 show high collagen reorganization capacity. Moreover, the results suggest that KGF mediates the anti-cancer effects on skin SCC

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O encontro de fatores preditivos de metástase cervical seria de grande valia para o tratamento de pacientes com tumores de alto potencial metastatizante e com pescoço clinicamente negativo. Procuramos encontrar fatores clínicos e histológicos em tumores iniciais de língua e soalho de boca que pudessem indicar a realização de um esvaziamento cervical eletivo.Foram estudados os seguintes fatores: sexo, idade, tabagismo, etilismo, raça, tamanho da lesão, sítio primário, dor, tempo de queixa, primeira queixa, aspecto macroscópico da lesão, infiltrado inflamatório peritumoral, grau de diferenciação da biópsia, desmoplasia, invasão vascular, invasão perineural e número de mitoses por 10 campos de maior aumento. Nenhum dos fatores estudados foi capaz de predizer a ocorrência de metástase cervical no período pré-operatório. Acreditamos que outros fatores devam ser estudados e explorados para que se consiga indicar o esvaziamento cervical eletivo de modo criterioso para o tratamento destas lesões.

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Adenocarcinomas of the cardia and gastroesophageal junction are peculiar entities with three different origins, which differ somewhat from other adenocarcinomas of the stomach in their clinical presentation and pathogenesis, and have a poorer prognosis. In this article the authors reviewed definitions, incidence and epidemiology, etiologic factors, genetic implications, clinical presentation, diagnosis, staging and treatment, with emphasis on the surgical approach, discussing the current management of these cancers. The prognostic factors related specifically to the cardia cancers are: esophageal invasion greater than 3cm, microscopic residual tumor and wall penetration (>T2). Preoperative workup should include computed tomography, and endoscopic ultrasonography and laparoscopy when available. Preoperative recognition of T3/ T4/N2 lesions should indicate inclusion in neo-adjuvant protocols whenever possible. The authors present the results of 46 resected cases of adenocarcinomas of the cardia and GE junction of the Instituto Nacional do Câncer- Brazil (1981-1995). Cure was intended in 29 and palliation in 17 patients. The most common type of resection was total gastrectomy with abdominal esophagectomy (28 cases). Morbidity (major and minor) occurred in 50% of the patients. The main causes were of respiratory origin and fistulas (19.6% each). Death occurred in 44% of the patients with fistula. Postoperative death until the 30th day occurred in 17.24% of the curative cases and in 23.52% of the palliative ones. The median survival time was 68.5 months for stage I, 25 months for stage II, 31 months for stage III and 12.5 months for stage IV diseases. The median survival time was 8 months for palliation and 28.5 months for cure. No long-term survival was obtained with the palliative group, whereas 25% survived five years of more in the curative group. The authors conclude that the surgical approach should be the one the surgeon feels more comfortable with. Complete removal of the disease proved by frozen section, splenectomy and D2 lymphadenectomy should be the standard therapy with curative intent.

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Appendiceal tumors are rare and usually presented as acute appendicitis. They are incidentally discovered at an emergency surgery, in which case the decision-making is very difficult. The purpose of this report is discuss to the most appropriate management for appendiceal tumors. A retrospective analysis of one case treated at HU-UEL was undertaken and the literature was reviewed. The conclusion is that frozen section should be done whenever the appendiceal findings are atypical. For appendiceal carcinoids greater than 2 cm and adenocarcinomas, a right hemicolectomy is recommended. Appendectomy is apropriate for patients whose carcinoid tumors are 1 cm in diameter or less and for carcinoid tumors between 1 cm and 2 cm without extensive lymphatic permeation and mesenteric invasion. Every case should be searched for synchronous tumors.

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Superior mesenteric vein invasion has historically been considered a contraindication for pancreatic cancer resection. Several studies have shown that in selected cases vascular resection can be performed safely. Many techniques have been used to reconstruct the venous flow. We describe one case of mesenteric superior vein resection and reconstrution of mesenteric-portal venous flow using the splenic vein during a pancreatoduodenectomy for pancreatic adenocarcinoma. The patient presented an extensive involvement of the superior mesenteric vein. A segmental resection with an end-to-end anastomosis of this vein and the splenic vein was accomplished after splenectomy. The patient had histologically confirmed negative margins. There was no hospital complications. These results show that the splenic vein can be an option for venous flow reconstruction when a segmental vascular resection is required during at pancreaticoduodenectomy.

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Chondrosarcoma is a rare malignant neoplasia that most of the time affects young adults. Its location is preferentially the pelvic and scapular girdle and surgery is its treatment of choice. There are no role for chemo or radiation therapy, because of their low index of response. We describe a case of a 45 year-old male patient with an extensive low grade right umerus chondrosarcoma. In spite of the local extension, there was no invasion of the shoulder neurovascular structures. Treatment proposed was the Tikhoff-Linberg procedure, and the operation was performed with success, with no complications. Free margins were obtained. The patient is now on two years follow-up with no evidence of recurrent disease and is able to drive, fish and carry packs. He can not abduct his arm, but he could not do that even before surgery, due to severe pain. We believe this is an excellent conservative approach to such tumors, that otherwise would require a forequarter amputation, and strongly recommend the technique.

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This overview examines some selected genetic mechanisms of cancer development. Strong evidence has been accumulated suggesting that alteration in either the struture or activity of proto-oncogene contributes to the development and for the maintenance of the malignant phenotype. Many factors are known to interfere with both normal and pathological controls of growth and differentiation of thyroid cells. Among them, some are oncogenes, like those encoding g-proteins (ras, gsp, TSH-R), encoding thyrosino kinases receptors (RET, trk, c-met, c-erb, BRAF) and encoding nuclear proteins (c-myc, e-fós). Others are anti-oncogenes (p53, p15, RB), by loss of the growth suppression ativity of the suppressive gene. Cancer cell invasion and metastasis are the major causes of morbidity and mortality in cancer patients. Many genes are involved in the mechanism of invasion and metastasis of thyroid tumors, like Nis, b-catenina, E-caderina, galectina-3, GLUT, telomerase, VEGT, nm-23. All these oncogenes, antioncogenes and tumor invasion and metastasis-related genes are analysed. Several clinical and prognostic factors have been proposed to identify patients at risk for the development of metastasis and death. The role of molecular genetics in this issue is discussed. However, other studies are needed to validate molecular alterations as an independent prognostic factor in thyroid cancer.

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Aortotracheal fistula is a rare condition that is invariably fatal if not diagnosed and surgically treated. Patients usually present with small intermittent hemoptysis. The findings using computerized tomography (CT) are usually diagnostic. CT should be considered in the initial investigation of patients suspected to have such a disease. A 62-year-old woman with a aneurysm of the descending thoracic aorta presented with new-onset back pain and hemoptysis. The hemoptysis was thought to be the result of invasion of the bronchial tree by the aneurysm.

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Biliary’s ascariasis is the most often ectopic site of this helminthiasis, but invasion of the worms into the gallbladder is quite rare. The autors report a case of a patient with clinical symptoms, compatible with cholecystitis induced by the worm, as shown by ultrasonography. Treatament was cholecystectomy and antihelmintic drug therapy with a good outcome.

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We present a case of non-resectable head pancreatic cancer by mesenteric venous invasion in which treatment with Gemcitabine (Gemzar) 1.000 mg/m 2 weekly for 3 weeks, followed by a 1-week rest, normalized CA 19.9 and promoted tumor resecability in a second operation (ultrasound, helicoidal tomography and magnetic ressonance exams). The value of the adjuvant treatment (radiochemotherapy) and the association with immunotherapy (Interferon) is discussed.