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Birt-Hogg-Dubé syndrome (MIM #135150) is characterized by the development of benign skin tumours called fibrofolliculomas, pulmonary cysts that may lead to pneumothorax and a high risk of developing kidney cancer. BHD is caused by mutations affecting the highly conserved protein folliculin (FLCN), which probably has a role in intracellular transport. Most of the research effort directed towards BHD has focused on understanding how loss of FLCN causes kidney cancer. The cutaneous manifestations have received comparatively little attention. Although understandable, it is unfortunate, as the fibrofolliculomas are highly accessible and thus potentially are an excellent system for trying to understand the basic pathobiology of BHD. Also, patients can be very much burdened by the cosmetic consequences of having hundreds of facial skin tumours. Our lack of insight into what drives fibrofolliculoma growth translates into a very limited therapeutic arsenal. Thus, paying attention to fibrofolliculomas has both basic science and practical benefits. In this review, we will discuss the state of the art regarding our understanding of fibrofolliculoma pathogenesis and indicate future directions for research.  相似文献   

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It has been proposed that matrix metalloproteinases (MMPs) play a role in tumor invasion. We determined protein expression of matrix metalloproteinase-9 (MMP-9) in colorectal cancer (CRC), corresponding normal mucosa and colorectal adenomas. For confirmation of immunohistochemical results MMP-9 TaqMan RT-PCR analysis was performed. Expression of MMP-9 was determined on paraffin embedded biopsy sections by immunohistochemistry in 31 CRC patients (from cancer tissue and corresponding normal mucosa) and in 30 patients with adenoma (nine adenomas with high grade of dysplasia). MMP-9 immunostaining was determined semi-quantitatively. For Taqman RT-PCR analyses normal mucosa (n = 5), adenoma without (n = 6) and with high grade dysplasia (n = 7) and CRC (n = 10) were investigated. Statistical analysis with ANOVA, LSD test and correlation analysis were performed. P value of <0.05 was considered significant. The MMP-9 expression in CRC was significantly higher compared to adenomas or the normal mucosa (P = 0.001). Significantly higher expression of MMP-9 has been observed in adenomas with high grade dysplasia compared to other adenomas or normal colon (P < 0.001). Diffuse strong MMP-9 expression was present in tumor as well as in stromal cells. In adenoma samples, dysplastic epithelial cells showed moderate intensive cytoplasmic MMP-9 expression, with a clear-cut differentiation between dysplastic and non-dysplastic areas. Staining intensity correlated with the grade of CRC. We demonstrate a significantly higher expression of MMP-9 in adenoma with high grade dysplasia-CRC sequence as compared to normal tissue. The over-expression of MMP-9 strongly suggests its association with colorectal carcinogenesis.  相似文献   

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EUS is the most sensitive imaging procedure for the detection of small solid pancreatic masses and is accurate in determining vascular invasion of the portal venous system. Even compared to the new CT-techniques EUS provides excellent results in preoperative staging of solid pancreatic tumors. Compared to helical CT-techniques EUS is less accurate in detecting tumor involvement of superior mesenteric artery. EUS staging and EUS-guided FNA can be performed in a single-step procedure, to establish the diagnosis of cancer. There is no known negative impact of tumor cell seeding due to EUS-FNA. Without FNA EUS and additional methods are not able to reliably distinguish between inflammatory and malignant masses.  相似文献   

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To investigate the expression levels of CXCL10 and CXCR3 in tumors from breast cancer patients randomized to adjuvant tamoxifen treatment or no endocrine treatment, in order to further study the connection to prognosis and prediction of tamoxifen treatment outcome. Immunohistochemistry on tissue microarrays from 912 breast cancer patients randomized to tamoxifen or no endocrine treatment. CXCR3 status was found to be a prognostic tool in predicting distant recurrence, as well as reduced breast cancer-specific survival. In patients with estrogen receptor (ER)-positive tumors, tumors with strong CXCL10 levels had improved effect of tamoxifen treatment in terms of local recurrence-free survival [risk ratio (RR) 0.46 (95 % CI 0.25–0.85, P = 0.01)] compared with patients with tumors expressing weak CXCL10 expression. Further, patients with ER-positive tumors with strong CXCR3 expression had an improved effect of tamoxifen in terms of breast cancer-specific survival [RR 0.34 (95 % CI 0.19–0.62, P < 0.001)] compared with the group with weak CXCR3 levels [RR 1.33 (95 % CI 0.38–4.79, P = 0.65)]. We show here for the first time that CXCL10 and CXCR3 expression are both predictors of favorable outcome in patients treated with tamoxifen.  相似文献   

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IntroductionsPancreatic ductal adenocarcinoma (frequently simply being referred to as “pancreatic cancer”) represents the most frequent neoplasm of the pancreas, accounting for 85% to 90% of all pancreatic tumors [1, 2]. According to the definition of the World Health Organization [1], it “prob-ably arises from and is phenotypically similar to pancre  相似文献   

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Mammalian target of rapamycin (mTOR) serine threonine kinase is the enzyme that regulates cancer cell growth by altering nutrient supplies to cancer cells. The neuropeptide (proline-rich peptide 1 (PRP-1)), galarmin, produced by the brain neurosecretory cells is a mTOR kinase inhibitor with powerful 80% antiproliferative cytostatic effect in a high-grade chondosarcoma and other mesenchymal tumors. However, the negative feedback loop of phosphatidylinositol 3 kinase–Protein kinase B (PKB), PI3K–AKT and PI3K–rat sarcoma (RAS)–mitogen-activated protein kinase (MAPK) activation is well documented for mTOR inhibitors. This study explored the involvement of those loops in drug resistance after the treatment with mTOR complex 1 (mTORC1) inhibitor, PRP-1. Multidrug resistance assay (MDR) demonstrated that this cytokine did not inhibit permeability glycoprotein-mediated MDR in chondrosarcoma. Phospho-MAPK array in human chondrosarcoma cell line treated with galarmin (10 μg/ml,) showed a strong upregulation of phosphorylated glycogen synthase kinase 3β (GSK3β) via activation of PI3K–AKT and MAPK feedback loops. Such GSK3β inactivation leads to β-catenin accumulation that entails drug resistance. The ability of cells to metastasize is reflected in their capacity to adhere to extracellular matrix and endothelium. Laminin cell adhesion assay demonstrated that PRP-1 in the same concentrations that inhibit mTOR kinase inhibited JJ012 chondrosarcoma cell adhesion. The neuropeptide did not have any effect on the expression of total focal adhesion kinase and its phosphorylated form. Thus, it was not accompanied by total HAT downregulation and total HDAC upregulation. Combinatorial treatments of PRP-1 with MAPK and PI3K/AKT inhibitors most probably will lead to full cytotoxicity overcoming drug resistance.  相似文献   

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Background Clinical observations suggest that prolonged treatment with megestrol can lead to Cushing-like symptoms, while withdrawal of prolonged treatment with megestrol may result in adrenal insufficiency. However, only little is known about the acute effects of megestrol on the hypothalamic–pituitary–adrenal (HPA) axis. As part of an endocrine study, we evaluated the acute effects of megestrol, hydrocortisone and placebo on morning cortisol and ACTH levels.Method Using a balanced double-blind design, ten healthy male subjects were treated at 11:00 p.m. and 8:00 a.m. with megestrol (total dose 320 mg), hydrocortisone (total dose 30 mg) or placebo. After 1 h of rest, blood was drawn at 10:00 a.m. and 10:30 a.m. for determination of cortisol and ACTH levels.Results Compared to placebo, acute administration of megestrol resulted in a significant decrease in morning ACTH and cortisol levels. The suppression of ACTH after pretreatment with megestrol was less pronounced than after pretreatment with hydrocortisone.Conclusions Our results suggest that megestrol exerts glucocorticoid-like effects and has an acute depressing effect on the HPA axis. Therefore alterations in the steroid system should be included in the differential diagnosis of all subjects under treatment with megestrol.  相似文献   

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Most of the experience with second-line chemotherapy for non-small-cell lung cancer (NSCLC) comes from small phase II trials, which have shown disappointing or inconsistent results. The notable exception has been docetaxel, which has been extensively studied as a second-line therapy for NSCLC. On the basis of consistent phase II activity, two large randomized phase III trials were conducted for patients with advanced NSCLC that had progressed either on or after first-line platinum-based therapy. In one trial, docetaxel, at either 100 or 75 mg/m2, was compared with a regimen of either vinorelbine or ifosfamide. In the second trial, docetaxel 75 to 100 mg/m2 was compared with best supportive care. Both trials showed significant improvement in survival, time to progression, and quality of life in the patients receiving docetaxel versus the control therapy. Based on these two large trials, it appears that the use of second-line therapy with single-agent docetaxel at a dose of 75 mg/m2 every 3 weeks is a reasonable practice in patients who maintain a good performance status.  相似文献   

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Engineered nanomaterials may adversely impact human health and environmental safety by nano–bio–eco interactions not fully understood. Their interaction with biotic and abiotic environments are varied and complicated, ranging from individual species to entire ecosystems. Their behavior, transport, fate, and toxicological profiles in these interactions, addressed in a pioneering study, are subsequently seldom reported. Biological, chemical, and physical dimension properties, the so-called multidimensional characterization, determine interactions. Intermediate species generated in the dynamic process of nanomaterial transformation increase the complexity of assessing nanotoxicity. We review recent progress in understanding these interactions, discuss the challenges of the study, and suggest future research directions.  相似文献   

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The aim of the study is to determine in-vitro effects of imipenem–tigecycline, imipenem–colistin and tigecycline–colistin against carbapenem-resistant Enterobacteriaceae (CRE) isolates. A total of 25 CRE isolates were included to the study. The minimum inhibition concentrations of imipenem, colistin-sulphate and tigecycline were determined with broth dilution method. Synergistic effects of imipenem–tigecycline, imipenem–colistin and tigecycline–colistin were investigated by microdilution checkerboard technique. All of the isolates were resistant to imipenem, whereas 25% of the isolates were resistant to colistin and tigecycline. Imipenem–colistin, imipenem–tigecycline and tigecycline–colistin combinations were synergistic against 40% (10/25), 24% (6/25), and 36% (9/25) of the isolates, respectively. Antagonism was observed in 8% (2/25) of the isolates in tigecycline–colistin combination. Tigecycline–colistin was the most effective (70% synergy) combination in Klebsiella spp. strains; whereas imipenem–colistin was the most effective (75% synergy) combination in Escherichia coli strains. Synergistic effect was variable and strain-depended against CRE isolates that have been tested.  相似文献   

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The peritoneal metastatic route of cancer dissemination is shared by cancers of the ovary and gastrointestinal tract. Once initiated, peritoneal metastasis typically proceeds rapidly in a feed-forward manner. Several factors contribute to this efficient progression. In peritoneal metastasis, cancer cells exfoliate into the peritoneal fluid and spread locally, transported by peritoneal fluid. Inflammatory cytokines released by tumor and immune cells compromise the protective, anti-adhesive mesothelial cell layer that lines the peritoneal cavity, exposing the underlying extracellular matrix to which cancer cells readily attach. The peritoneum is further rendered receptive to metastatic implantation and growth by myofibroblastic cell behaviors also stimulated by inflammatory cytokines. Individual cancer cells suspended in peritoneal fluid can aggregate to form multicellular spheroids. This cellular arrangement imparts resistance to anoikis, apoptosis, and chemotherapeutics. Emerging evidence indicates that compact spheroid formation is preferentially accomplished by cancer cells with high invasive capacity and contractile behaviors. This review focuses on the pathological alterations to the peritoneum and the properties of cancer cells that in combination drive peritoneal metastasis.  相似文献   

13.
Neuroendocrine tumors (NETs) are considered to be rare but, during the last two decades, their incidence and prevalence has considerably increased in gastro–entero–pancreatic (GEP) NETs. Most GEP-NETs express somatostatin receptors, which could be targets for treatment. The development of somatostatin analogs for treatment of functioning NETs was a revolution in the treatment of these patients and is still a cornerstone for managing hormone-related clinical symptoms. Furthermore, somatostatin analogs have also demonstrated an anti-tumor effect, with stabilization of tumor growth over long periods of time. The development of a long-acting formulation of octreotide long-acting release (LAR®) significantly improved the quality of life for patients with functioning NETs in terms of necessitating only monthly injections. The side effects are few and easily manageable. In the future, somatostatin analogs will continue to be a major treatment option for functioning NETs, but will be combined with other biologicals, such as a-interferons, mTOR inhibitors and VEGF inhibitors. A new multireceptor somatostatin analog, SOM230 (pasireotide), as well as chimeric molecules, such as dopastatin (a combination of a somatostatin analogue plus a dopamine agonist), will come into the clinical management of GEP-NETs.  相似文献   

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Objective: Accurate staging of patients with pancreatic cancer is crucial to clarify whether meaningful resection is indeed possible. Staging laparoscopy has been suggested as a tool for staging which may spare up to two-fifth of these patients from undergoing nontherapeutic laparotomy. A controversy exists, however, as to whether the procedure should be used routinely or selectively in these patients with no evidence of metastasis on noninvasive staging. This review aims to evaluate the available literature critically, identify its limitations and address the existing controversies. Methods: The current available English literature was reviewed on this topic. Results: A direct and conclusive comparison of the controversial literature is difficult because of inconsistent use of high-quality CT scans, different study designs and dissimilarity of judgment for non-resectability among patients staged by laparoscopy. However, recent studies reveal that not more than 14% of the patients benefit from diagnostic laparoscopy when a dual-contrast thin cut and 3-D digital reformatting CT scan has been performed previously. Conclusion: We conclude that routine use of diagnostic laparoscopy does not appear warranted in all patients with pancreatic cancer, especially for patients with early-staged pancreatic cancer or non-pancreatic periampullary cancers, because diagnostic laparoscopy is costly and ultrasonography is largely operator-dependent. Rather, selective use is appropriate, especially in patients with a large primary tumor, a tumor in the body or tail of the pancreas, equivocal findings of metastasis on CT, the presence of ascites, severe weight loss, hypoalbuminemia, and a markedly elevated CA 19–9.  相似文献   

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Pancreatic ductal adenocarcinoma is a dismal disease with a median survival below 6 months and a 5 year survival rate below 1%. High mortality is due to early lymphatic and hematogenic dissemination. Effective therapies for local advanced or metastatic tumors are missing and curative resected patients relapse in over 80% of the cases. Together this findings reflects the aggressive biology of the disease. Here we describe molecular mechanisms leading to unrestrained proliferation, insensitivity to growth inhibitory signals, evasion of apoptosis, limitless replicative potential, tissue invasion, metastasis and sustained angiogenesis.  相似文献   

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Objective: To assess current role of laparoscopic resection for pancreatic cancer, so as to improve the surgical management of pancreatic cancer. Methods: A comprehensive review of articles from PubMed was carried out. Results: Cur- rently, the advantages of a complete laparoscopic pancreatoduodenectomy (LPD) are still outweighed by the morbidity associ- ated with the procedure. However, laparoscopic distal pancreatectomy (LDP) offers patients benefits in terms of postoperative recovery and the length of hospital stay with similar morbidity and mortality to open surgery. Hand-assisted laparoscopic sur- gery can help to overcome the limitation of a complete laparoscopic surgery while maintaining a minimally invasive approach. Conclusion: Current literature suggests that laparoscopic resection of pancreatic cancer is feasible and safe in experienced hands. The hand-assisted laparoscopic surgery shows a promising future in pancreatic cancer surgery.  相似文献   

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Here, we present the basic concept and theoretical framework of a scientific hypothesis called Cancer Evolution–Development (“Cancer Evo-Dev”), based on our recent studies of the molecular mechanisms by which chronic infection with the hepatitis B virus induces hepatocarcinogenesis, together with related advances in that field. Several aspects central to our hypothesis are presented:
  • ■ Immune imbalance—caused by the interaction of genetic predispositions and environmental exposures such as viral infection—is responsible for the maintenance of chronic non-resolving inflammation. Non-resolving inflammation promotes the occurrence and progression of cancers, characterized by an evolutionary process of “mutation–selection–adaptation” for both viruses and host cells.
  • ■ Under a microenvironment of non-resolving inflammation, proinflammatory factors promote mutations in viral or host genomes by transactivation of the expression of cytidine deaminases and their analogues. Most cells with genomic mutations and mutated viruses are eliminated in the competition for survival in the inflammatory microenvironment. Only a small percentage of the mutated cells that alter their survival signal pathways and exhibit the characteristics of “stem-ness” can survive and function as cancer-initiating cells.
  • ■ Cancers generally develop with properties of “backward evolution” and “retro-differentiation,” indicating the indispensability of stem-like signal pathways in the evolution and development of cancers.
The hypothesis of Cancer Evo–Dev not only lays the theoretical foundation for understanding the mechanisms by which inflammation promotes the development of cancers, but also plays an important role in specific prophylaxis, prediction, early diagnosis, and targeted treatment of cancers.  相似文献   

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