990 resultados para CHFR, nasopharyngeal carcinoma, promoter hypermethylation
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AbstractRenal cell carcinoma (RCC) is the seventh most common histological type of cancer in the Western world and has shown a sustained increase in its prevalence. The histological classification of RCCs is of utmost importance, considering the significant prognostic and therapeutic implications of its histological subtypes. Imaging methods play an outstanding role in the diagnosis, staging and follow-up of RCC. Clear cell, papillary and chromophobe are the most common histological subtypes of RCC, and their preoperative radiological characterization, either followed or not by confirmatory percutaneous biopsy, may be particularly useful in cases of poor surgical condition, metastatic disease, central mass in a solitary kidney, and in patients eligible for molecular targeted therapy. New strategies recently developed for treating renal cancer, such as cryo and radiofrequency ablation, molecularly targeted therapy and active surveillance also require appropriate preoperative characterization of renal masses. Less common histological types, although sharing nonspecific imaging features, may be suspected on the basis of clinical and epidemiological data. The present study is aimed at reviewing the main clinical and imaging findings of histological RCC subtypes.
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AIMS: Mitofusin-2 (Mfn2) expression is dysregulated in vascular proliferative disorders and its overexpression attenuates the proliferation of vascular smooth muscle cells (VSMCs) and neointimal lesion development after balloon angioplasty. We sought to gain insight into the mechanisms that control Mfn2 expression in VSMCs. METHODS AND RESULTS: We cloned and characterized 2 kb of the 5'-flanking region of the human Mfn2 gene. Its TATA-less promoter contains a CpG island. In keeping with this, 5'-rapid amplification of cDNA ends revealed six transcriptional start sites (TSSs), of which TSS2 and TSS5 were the most frequently used. The strong CpG island was found to be non-methylated under conditions characterized by large differences in Mfn2 gene expression. The proximal Mfn2 promoter contains six putative Sp1 motifs. Sp1 binds to the Mfn2 promoter and its overexpression activates the Mfn2 promoter in VSMCs. Chemical inhibition of Sp1 reduced Mfn2 expression, and Sp1 silencing reduced transcriptional activity of the Mfn2 promoter. In keeping with this view, Sp1 and Mfn2 mRNA levels were down-regulated in the aorta early after an atherogenic diet in apolipoprotein E-knockout mice or in VSMCs cultured in the presence of low serum. CONCLUSION: Sp1 is a key factor in maintaining basal Mfn2 transcription in VSMCs. Given the anti-proliferative actions of Mfn2, Sp1-induced Mfn2 transcription may represent a mechanism for prevention of VSMC proliferation and neointimal lesion and development.
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AIMS: Mitofusin-2 (Mfn2) expression is dysregulated in vascular proliferative disorders and its overexpression attenuates the proliferation of vascular smooth muscle cells (VSMCs) and neointimal lesion development after balloon angioplasty. We sought to gain insight into the mechanisms that control Mfn2 expression in VSMCs. METHODS AND RESULTS: We cloned and characterized 2 kb of the 5'-flanking region of the human Mfn2 gene. Its TATA-less promoter contains a CpG island. In keeping with this, 5'-rapid amplification of cDNA ends revealed six transcriptional start sites (TSSs), of which TSS2 and TSS5 were the most frequently used. The strong CpG island was found to be non-methylated under conditions characterized by large differences in Mfn2 gene expression. The proximal Mfn2 promoter contains six putative Sp1 motifs. Sp1 binds to the Mfn2 promoter and its overexpression activates the Mfn2 promoter in VSMCs. Chemical inhibition of Sp1 reduced Mfn2 expression, and Sp1 silencing reduced transcriptional activity of the Mfn2 promoter. In keeping with this view, Sp1 and Mfn2 mRNA levels were down-regulated in the aorta early after an atherogenic diet in apolipoprotein E-knockout mice or in VSMCs cultured in the presence of low serum. CONCLUSION: Sp1 is a key factor in maintaining basal Mfn2 transcription in VSMCs. Given the anti-proliferative actions of Mfn2, Sp1-induced Mfn2 transcription may represent a mechanism for prevention of VSMC proliferation and neointimal lesion and development.
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Abstract Objective: To determine the rates of diagnostic underestimation at stereotactic percutaneous core needle biopsies (CNB) and vacuum-assisted biopsies (VABB) of nonpalpable breast lesions, with histopathological results of atypical ductal hyperplasia (ADH) or ductal carcinoma in situ (DCIS) subsequently submitted to surgical excision. As a secondary objective, the frequency of ADH and DCIS was determined for the cases submitted to biopsy. Materials and Methods: Retrospective review of 40 cases with diagnosis of ADH or DCIS on the basis of biopsies performed between February 2011 and July 2013, subsequently submitted to surgery, whose histopathological reports were available in the internal information system. Biopsy results were compared with those observed at surgery and the underestimation rate was calculated by means of specific mathematical equations. Results: The underestimation rate at CNB was 50% for ADH and 28.57% for DCIS, and at VABB it was 25% for ADH and 14.28% for DCIS. ADH represented 10.25% of all cases undergoing biopsy, whereas DCIS accounted for 23.91%. Conclusion: The diagnostic underestimation rate at CNB is two times the rate at VABB. Certainty that the target has been achieved is not the sole determining factor for a reliable diagnosis. Removal of more than 50% of the target lesion should further reduce the risk of underestimation.
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Head and neck squamous cell carcinoma (HNSCC) arises in the oral cavity,oropharynx,larynx and hypopharynx.Recent works highlighted a subset of HNSCC related to Human Papilloma Virus (HPV) with complete differet molecular progression and associated with a better prognosis than HPV-negative HNSCC. The aim of this work is to culture HPV-positive tumor cells and transfect them with shRNA-expressing plasmids, to prepare RNA from the control and shRNA-treated cells and to measure gene expression....
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Abstract Objective: The present study was aimed at describing a single-institution experience in the curative treatment of patients diagnosed with locally advanced hypopharyngeal squamous cell carcinoma. Materials and Methods: Data concerning all patients treated for locally advanced hypopharyngeal squamous cell carcinoma between January 2006 and June 2012 were reviewed. Results: A total of 144 patients were included in the present study. The median follow-up period was 36.6 months. Median survival was 26 months, and 2-year and 5-year overall survival rates were, 51% and 30.5%, respectively. Median recurrence-free survival was 18 months and 2-year and 5-year recurrence-free survival rates were 42.8% and 28.5%, respectively. Conclusion: The outcomes in the present series are in line with the literature.
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Purpose: We aimed to determine the impact of SPECT/CT performed in addition to whole-‐body scintigraphy augmented with prone lateral views in patients with well-‐differentiated thyroid carcinoma. Methods and Materials: This retrospective study included 141 patients (87 female, 54 male, mean age 47 years) with well-‐differentiated thyroid carcinoma (105 papillary, 31 follicular, 1 Hürthle cell and 4 poorly differentiated) treated with radioiodine therapy (1000-7400 MBq). Patients were referred for either first postsurgical therapy (n=76) or further treatment (n=65). Two nuclear medicine physicians interpreted the scans in consensus (first whole-‐body scintigraphy with prone lateral view, then SPECT/CT) reporting abnormal iodine uptake in the thyroid bed, lymph nodes and distant metastasis. The corresponding ATA risk score was calculated for each patient before and after SPECT/CT, as well as change in disease extension Results: The analysis showed a difference between scintigraphy and SPECT/CT in n=17 lesions in 14 patients (9.9%): 12 were described as suspicious on scintigraphy and could be considered as benign on SPECT/CT (3 corresponded to local iodine uptake, 6 to lymph nodes metastases and 3 to distant metastases). The others 5 corresponded to metastases (4 lymph nodes and 1 distant) that were not seen on whole-‐body scintigraphy augmented with prone lateral views. In 10 of 141 (7.1%) patients, we observed a change in ATA risk stratification, with a risk increase in 4 of them (2.8%). Conclusion: SPECT/CT allowed detecting 5 focal lesions missed on planar scintigraphy, and to precise benignity of 12 suspicious lesions on planar scintigraphy. Moreover, SPECT/CT improved the risk stratification in 10 patients with a significant change in the patient management
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5-Aminolevulinic acid (ALA) is a heme precursor accumulated in acute intermittent porphyria (AIP), which might be associated with hepatocellular carcinoma (HCC) in symptomatic patients. Under metal catalyzed oxidation, ALA and its cyclic dimerization product, 3,6-dihydropyrazine-2,5-dipropanoic acid, produce reactive oxygen species that damage plasmid and calf thymus DNA bases, increase the steady state level of 8-oxo-7,8-dihydro-2´-deoxyguanosine in liver DNA and promote mitochondrial DNA damage. The final product of ALA, 4,5-dioxovaleric acid (DOVA), is able to alkylate guanine moieties, producing adducts. ALA and DOVA are mutagenic in bacteria. This review shows an up-to-date literature data that reinforce the hypothesis that the DNA damage induced by ALA may be associated with the development of HCC in AIP patients.
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TCF7L2 is the susceptibility gene for Type 2 diabetes (T2D) with the largest effect on disease risk that has been discovered to date. However, the mechanisms by which TCF7L2 contributes to the disease remain largely elusive. In addition, epigenetic mechanisms, such as changes in DNA methylation patterns, might have a role in the pathophysiology of T2D. This study aimed to investigate the differences in terms of DNA methylation profile of TCF7L2 promoter gene between type 2 diabetic patients and age- and Body Mass Index (BMI)- matched controls. We included 93 type 2 diabetic patients that were recently diagnosed for T2D and exclusively on diet (without any pharmacological treatment). DNA was extracted from whole blood and DNA methylation was assessed using the Sequenom EpiTYPER system. Type 2 diabetic patients were more insulin resistant than their matched controls (mean HOMA IR 2.6 vs 1.8 in controls, P<0.001) and had a poorer beta-cell function (mean HOMA B 75.7 vs. 113.6 in controls, P<0.001). Results showed that 59% of the CpGs analyzed in TCF7L2 promoter had significant differences between type 2 diabetic patients and matched controls. In addition, fasting glucose, HOMA-B, HOMA-IR, total cholesterol and LDL-cholesterol correlated with methylation in specific CpG sites of TCF7L2 promoter. After adjustment by age, BMI, gender, physical inactivity, waist circumference, smoking status and diabetes status uniquely fasting glucose, total cholesterol and LDL-cholesterol remained significant. Taken together, newly diagnosed, drug-naïve type 2 diabetic patients display specific epigenetic changes at the TCF7L2 promoter as compared to age- and BMI-matched controls. Methylation in TCF7L2 promoter is further correlated with fasting glucose in peripheral blood DNA, which sheds new light on the role of epigenetic regulation of TCF7L2 in T2D.
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Sugar intake has dramatically increased during the last few decades. Specifically, there has been a clear trend towards higher consumption of fructose and high fructose corn syrup, which are the most common added sugars in processed food, soft drinks and other sweetened beverages. Although still controversial, this rising trend in simple sugar consumption has been positively associated with weight gain and obesity, insulin resistance and type 2 diabetes mellitus and non-alcoholic fatty liver disease. Interestingly, all of these metabolic alterations have also been related to the development of hepatocellular carcinoma. The purpose of this review is to discuss the evidence coming from epidemiological studies and data from animal models relating the consumption of simple sugars, and specifically fructose, with an increased risk of hepatocellular carcinoma and to gain insight into the putative molecular mechanisms involved.
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We present a 53-year-old man with a vocal cord paralysis observed as a primary manifestation of lung carcinoma. Tc-99m MDP whole body bone scan was performed and resulted in a normal scintiscan. The bone scan did not reveal any suspicious foci of uptake. The possibility of bone metastasis was taken into consideration. A whole body F18-FDG-PET scan showed intense uptake in the left upper lung corresponding to the primary tumor. A bronchial biopsy confirmed infiltration by small cell lung carcinoma (SCLC). SCLC is composed of poorly differentiated, rapidly growing cells with diseases usually occurring centrally rather than peripherally. It metastasizes early. The whole-body F18-FDG-PET scan clearly demonstrated a focus of increased uptake in the second lumbar vertebral body suspicious for osteolytic metastasis. A lytic bone metastasis was confirmed by MRI. The patient then received therapy and underwent follow up abdominal CT. The scan showed blastic changes in the L2 vertebra suggesting response to treatment.
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Molekyylimarkkerit ja pitkäaikainen alfainterferonihoito munuaissyövässä Munuaissyöpäpotilaiden viiden vuoden elossaololuku on noin 50 %. Aikaisempien tutkimuksien mukaan viiden vuoden elossaololuku metastasoituneessa munuaissyövässä on 3-16 %, kun käytettiin alfainterferonia sisältävää hoitoa. Tyypillisesti alfainterferonia on käytetty vähemmäin kuin 6 kuukautta. Avoimia kysymyksiä ovat alfainterferonin optimaalinen hoitoannos ja hoidon kesto yksin tai yhdessä uusien täsmähoitojen kanssa. Tärkeimmät tavoitteet olivat tutkia 1) jaksotetun pitkäaikaisen alfainterferonihoidon tehoa ja siedettävyyttä metastasoituneessa munuaissyövässä ja 2) p53-, Ki-67- ja COX-2-proteiinituotannon ennusteellista merkitystä munuaissyövässä. Tutkimuksessa 117 metastasoituneelle munuaissyöpää sairastaneelle potilaalle etsittiin yksilöllinen hänen sietämänsä maksimaalinen hoitoannos rekombinanttia alfa2a-interferonia (Roferon-ATM). Hoitoa pyrittiin jatkamaan 24 kuukauden ajan. Kolmen hoitoviikon jälkeen pidettiin yhden viikon tauko. Hoito lopetettiin, jos ilmaantui vakavia haittavaikutuksia tai tauti eteni. Toisessa tutkimuksessa proteiinituotanto analysoitiin immunohistokemiallisesti munuaissyöpäpotilaiden kasvainnäytteistä, joita oli säilytetty parafiinissa. Kasvainnäytteet oli otettu talteen munuaisen poistoleikkauksen yhteydessä. Nämä potilaat jaettiin kolmeen eri ryhmään: metastasointi primaarivaiheessa (n=29), metastasointi myöhemmin (n=37) ja ei metastasointia (n=51). Keskimääräinen alfainterferonihoidon kesto oli 11 kuukautta (kk) [0,5 – 32 kk]. Objektiivinen hoitovaste todettiin 17 %:lla, tautitilanne pysyi ennallaan 42 %:lla ja myöhäinen vaste (yli 12 kk:tta hoidon aloittamisesta) todettiin 3 %:lla. Aika vasteen saavuttamisesta taudin etenemiseen oli keskimäärin 8 kk ja elinaika 19,1 kk. Viiden vuoden elossaololuku oli 16 %. Jos metastasoituneella munuaissyöpäpotilaalla oli keuhkometastasointi, hän selvisi todennäköisemmin viisi vuotta kuin muut potilaat. Henkeä uhkaavia sivuvaikutuksia ei todettu. Yli 12 kk:n ajan kestävä alfainterferonihoito on hyödyllistä niille potilaille, jotka ovat saaneet objektiivisen hoitovasteen tai tautitilanne on pysynyt ennallaan. Positiivinen p53- ja Ki-67-ekspressio yhdessä viittaavat suureen metastasoinnin todennäköisyyteen. Positiivinen COX-2-ekspressio viittaa viivästyneeseen metastaasien ilmaantumiseen. Metastasoituneilla potilailla positiiviset p53- ja Ki-67-ekspressiot viittaavat huonoon ennusteeseen, mutta positiivinen COX-2 ekspressio viittaa suotuisaan ennusteeseen. Positiivinen COX-2- ja negatiivinen Ki-67-ekspressio yhdessä viittaavat parantuneeseen ennusteeseen metastasoituneessa munuaissyövässä.
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Gene therapy aims to treat diseases by introducing genetic material to the diseased tissue. For cancer treatment it is important to destroy cancerous cells; this can be achieved by introducing a gene, which induces cell death or by allowing viral vectors to replicate, which also results in destruction of cancerous cells. For cardiac diseases the approach is more like the former, except the gene produces beneficial effects, like angiogenesis. Adenoviruses have many beneficial qualities, which make the virus an interesting gene therapy vector; it can be produced relatively easily, its manipulation is quite easy and it has naturally broad tropism. By removing or replacing certain genes in the adenoviral genome, it can be made non-replicative. In this study, adenoviral receptor expression patterns were characterized in both head and neck squamous cell carcinoma and the human heart. Adenovirus serotype 5 receptor expression in head and neck cancer cell lines was found to be highly variable between cell lines and overall at lower levels, while Ad35 receptor expression was more uniform and at higher levels in all analyzed cell lines. It was also shown that a hybrid virus Ad5/35 is able to infect cells refractory to Ad5, which correlates with receptor expression in these cells. Furthermore, this difference in infection properties extends to cell killing efficiency in case of conditionally replicative viruses. Expression levels of adenoviral receptors CAR, CD46, CD86 and αv-integrins were found to be high both in normal and dilated cardiomyopathy heart tissue. The receptor levels also correlate with transduction efficiency after intracardiac injection. Ad5 showed superior transduction ability compared with Ad5/35, but evoked also a more profound immune reaction when administered this way. Adenoviral gene therapy vectors are the most used delivery vehicles in clinical trials to date. These vectors have proven to be well tolerated and positive results have been obtained when combined with traditional treatments, although poor transduction efficiency has often been reported due to low-level expression of viral receptors on target cells. In spite of this, the results are encouraging and merit for further research.
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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