Photo-induced lattice distortion in 2H-MoTe2 probed by time-resolved core level photoemission.

The technological interest in MoTe2 as a phase engineered material is related to the possibility of triggering the 2H-1T' phase transition by optical excitation, potentially allowing for an accurate patterning of metallic areas into a semiconducting canvas via laser irradiation. In this paper, we investigate the photo-induced modifications of a bulk 2H-MoTe2 crystal by means of time-resolved X-ray photoemission spectroscopy. We observe that in the microsecond timescale, the core levels shift to higher kinetic energies due to surface photovoltage fields, while in the sub-nanosecond range, the photoemission peaks shift in the opposite direction. With the support of DFT calculations, we ascribe the latter effect to the deformation of the lattice in the out-of-plane direction, which is along the pathway for the 2H-1T' phase transition. Our data indicate an intermediate lattice excitation state with a measured lifetime in the order of 600 ps, in which the displacement of Mo and Te atoms causes the Te 4d electrons to shift towards higher binding energies.

Vibrational fingerprint of localized excitons in a two-dimensional metal-organic crystal.

Long-lived excitons formed upon visible light absorption play an essential role in photovoltaics, photocatalysis, and even in high-density information storage. Here, we describe a self-assembled two-dimensional metal-organic crystal, composed of graphene-supported macrocycles, each hosting a single FeN4 center, where a single carbon monoxide molecule can adsorb. In this heme-like biomimetic model system, excitons are generated by visible laser light upon a spin transition associated with the layer 2D crystallinity, and are simultaneously detected via the carbon monoxide ligand stretching mode at room temperature and near-ambient pressure. The proposed mechanism is supported by the results of infrared and time-resolved pump-probe spectroscopies, and by ab initio theoretical methods, opening a path towards the handling of exciton dynamics on 2D biomimetic crystals.

Diclofenac epolamine topical patch for the treatment of pain.

Topical nonsteroidal anti-inflammatory drugs produce local pain relief while avoiding systemic adverse events, thanks to minimal systemic absorption. This review evaluates the effectiveness and safety of a topical diclofenac preparation, diclofenac epolamine (DHEP) patch 1.3% or diclofenac epolamine patch with heparin as excipient (DHEP+H) in treating mild-to-moderate pain. DHEP patch was associated with significant pain relief and improved function in numerous pain conditions, from minor soft tissue injuries to osteoarthritis and myofascial pain syndromes. Tolerability was good-to-excellent in all studies, with no serious adverse events. DHEP+H further improved efficacy without affecting tolerability. This patch is effective and safe for localized mild-to-moderate somatic pain.

A preliminary assessment of a new dedicated endodontic software for use with CBCT images to evaluate the canal complexity of mandibular molars.

AIM: To investigate in vivo the complexity of canals within mesial roots of mandibular molars using 3D Endo™ software linked to CBCT images. METHODOLOGY: The CBCT images of 100 mandibular first molars were analysed using the 3D Endo™ software. The number of canals in the mesial roots, the presence of apical confluences, the canal lengths and the canal configurations using Vertucci's classification were evaluated in buccolingual (BL) and mesiodistal (MD) views. The software allowed the visualization of canal trajectories in three dimensions using a coloured outline, which was used to develop a new objective scoring system to provide an overall assessment of canal complexity. Data were analysed statistically using anova and t-tests with the significance set at P < 0.05. RESULTS: Vertucci type IV canals were found in 44% of the cases, whilst 54% were type II. The mean distance from the apical foramen to the orifice was 13.15 mm (±1.21) and that between a confluence and the foramen, 2.81 mm (±1.13). The number of curvatures and the canal complexity scores in the MD view were significantly higher than in the BL view (P < 0.05). The scores were not directly correlated to the canal (MB versus ML), to the canal length or to the presence of confluences. CONCLUSIONS: 3D Endo software features the automatic detection and measurement of several anatomical canal parameters, and is a promising tool for the study of canal complexity in vivo. The unpredictable anatomy of the mesial roots of mandibular molars highlights the value of a three-dimensional preoperative evaluation of each case. The proposed scoring system aims to provide the clinician with an overall assessment of canal complexity.

Regulation of miR-483-3p by the O-linked N-acetylglucosamine transferase links chemosensitivity to glucose metabolism in liver cancer cells.

The miR-483-3p is upregulated in several tumors, including liver tumors, where it inhibits TP53-dependent apoptosis by targeting the pro-apoptotic gene BBC3/PUMA. The transcriptional regulation of the miR-483-3p could be driven by the ß-catenin/USF1 complex, independently from its host gene IGF2, and we previously demonstrated that in HepG2 hepatoblastoma cells carrying wild-type TP53 the upregulation of the miR-483-3p overcomes the antitumoral effects of the tumor-suppressor miR-145-5p by a mechanism involving cellular glucose availability. Here we demonstrate that in HepG2 cells, the molecular link between glucose concentration and miR-483-3p expression entails the O-linked N-acetylglucosamine (O-GlcNAc) transferase (OGT), which stabilizes the transcriptional complex at the miR-483 promoter. HepG2 cells showed reduced miR-483-3p expression and increased susceptibility to 5-fluorouracil (5-FU)-induced apoptosis in presence of the inhibitor of glycolysis 2-deoxy-d-glucose (2-DG). However, in vivo experiments showed that HepG2 cells with higher miR-483-3p expression were selected during tumor progression regardless of 5-FU treatment. Furthermore, treatment with 2-DG alone did not significantly reduce HepG2 xenograft load in immunodeficient mice. In conclusion, we show that in HepG2 cells glucose uptake increases the expression of the oncogenic miR-483-3p through the OGT pathway. This suggests that depletion of the miR-483-3p may be a valuable therapeutic approach in liver cancer patients, but the use of inhibitors of glycolysis to achieve this purpose could accelerate the selection of resistant neoplastic cell clones.

Allele-specific loss and transcription of the miR-15a/16-1 cluster in chronic lymphocytic leukemia.

Deregulation of the miR-15a/16-1 cluster has a key role in the pathogenesis of chronic lymphocytic leukemia (CLL), a clinically heterogeneous disease with indolent and aggressive forms. The miR-15a/16-1 locus is located at 13q14, the most frequently deleted region in CLL. Starting from functional investigations of a rare SNP upstream the miR cluster, we identified a novel allele-specific mechanism that exploits a cryptic activator region to recruit the RNA polymerase III for miR-15a/16-1 transcription. This regulation of the miR-15a/16- locus is independent of the DLEU2 host gene, which is often transcribed monoallellically by RPII. We found that normally one allele of miR-15a/16-1 is transcribed by RNAPII, the other one by RNAPIII. In our subset of CLL patients harboring 13q14 deletions, exclusive RNA polymerase III (RPIII)-driven transcription of the miR-15a/16-1 was the consequence of loss of the RPII-regulated allele and correlated with high expression of the poor prognostic marker ZAP70 (P=0.019). Thus, our findings point to a novel biological process, characterized by double allele-specific transcriptional regulation of the miR-15a/16-1 locus by alternative mechanisms. Differential usage of these mechanisms may distinguish at onset aggressive from indolent forms of CLL. This provides a basis for the clinical heterogeneity of the CLL patients carrying 13q14 deletions.

Distinctive gene expression profiles in Balb/3T3 cells exposed to low dose cobalt nanoparticles, microparticles and ions: potential nanotoxicological relevance.

Size-dependent characteristics of novel engineered nanomaterials might result in unforeseen biological responses and toxicity. To address this issue, we used cDNA microarray analysis (13443 genes) coupled with bioinformatics and functional gene annotation studies to investigate the transcriptional profiles of Balb/3T3 cells exposed to a low dose (1 μM) of cobalt nanoparticles (CoNP), microparticles (CoMP) and ions (Co2+). CoNP, CoMP and Co2+ affected 124, 91 and 80 genes, respectively. Hierarchical clustering revealed two main gene clusters, one up-regulated, mainly after Co2+, the other down-regulated, mainly after CoNP and CoMP. The significant Gene Ontology (GO) terms included oxygen binding and transport and hemoglobin binding for Co2+, while the GOs of CoMP and CoNP were related to nucleus and intracellular components. Pathway analysis highlighted: i) mitochondrial dysfunction for Co2+, ii) signaling, activation of innate immunity, and apoptosis for CoNP, and iii) cell metabolism, G1/S cell cycle checkpoint regulation and signaling for CoMP. Unlike ions, particles affected toxicologically-relevant pathways implicated in carcinogenesis and inflammation.

Multimodal approach to mild biliary pancreatitis based on a risk stratification of choledocholithiasis.

AIM: The management of acute mild biliary pancreatitis is multidisciplinary and still presents controversies in the diagnostic and therapeutic strategies. The aim of this retrospective study is to establish if a risk stratification of choledocholithiasis can optimize the employment of technological resources and medical competence in the treatment of individual patients in a tailored way. Our personal experience has then been compared with international literature. The main end-point was to evaluate the incidence of recurrence of acute pancreatitis. Secondary end point was to propose an affordable diagnostic and therapeutic algorithm for this relatively common disease. METHODS: One hundred and one (101) patients affected by acute mild biliary pancreatitis were admitted in the Department of Patologia Chirurgica of "Ospedale SS. Annunziata" of Chieti from January 2004 to June 2011. Patients were divided in three groups; high (I), medium (II) and low risk (III) of choledocholithiasis (CBDS) according to clinical, laboratory and instrumental criteria. On the base of this division, patients in group I were subjected to ERCP with endoscopic sphinterotomy (ES) and subsequent laparoscopic cholecystectomy (LC). Group II patients underwent to MRCP, if positive for CBDS followed by ES and subsequently LC, if negative for CBDS directly LC. Group III patients underwent directly to LC associated with intra-operative cholangiography in selected cases. RESULTS: No recurrence of acute pancreatitis was observed in patients who completed the diagnostic and therapeutic procedures. CONCLUSION: We believe that the application of a patient stratification in risk groups for choledocholithiasis can optimize the use of medical and technological resources and helps to address a patient for a specific and more appropriate diagnostic and therapeutic investigation allowing, at the same time, to identify patients who can usefully undergo to a simplified diagnostic and therapeutic approach.

Análise ultrassonográfica tardia do stent eluidor de sirolimus firebird TM / Long-term ultrasound analysis of the firebird TM sirolimus eluting stent

Introdução: Os stents farmacológicos (SFs) melhoraram a evolução clínica dos pacientes submetidos a intervenção coronária percutânea (ICP). Novos SFs foram desenvolvidos com o propósito de superar as atuais limitações da geração mais antiga de SFs. Este estudo teve como objetivo avaliar os aspectos angiográfico e ultrassonográfico tardios do SF eluidor de sirolimus FirebirdTM. Métodos: Entre dezembro de 2007 e março de 2008, 15 pacientes portadores de lesões de novo foram submetidos a ICP com implante de stent FirebirdTM. Avaliação com angiografia e USIC foi realizada em todos os pacientes aos 24 meses de seguimento. O objetivo primário foi a avaliação da perda luminal tardia à angiografia coronária quantitativa e o porcentual de obstrução volumétrica intrastent pelo ultrassom intracoronário (USIC) Resultados: A média de idade foi de 57 ± 7,1 anos, 87% eram do sexo masculino e 27% eram diabéticos. A artéria descendente anterior foi o vaso mais frequentemente tratado (36%) e a maioria das lesões era do tipo B2/C (82%). Aos 24 meses, a perda luminal tardia foi de 0,17 ± 0,36 mm e a revascularização do vaso tratado foi de 6,6%. O porcentual de obstrução volumétrica intrastent foi de 9,6 ± 4,6%. Não houve casos de óbito, infarto ou trombose de stent. Conclusões: Neste estudo de centro único brasileiro, o stent FirebirdTM apresentou resultados tardios satisfatórios. Esses achados, em conjunto com os disponíveis na literatura, fornecem evidências adicionais para o uso do stent FirebirdTM na prática clínica diária.

BACKGROUND: Drug eluting stents (DES) have improved the clinical outcomes of patients undergoing percutaneous coronary interventions (PCI). New DES have been developed with the purpose of overcoming the current limitations of the older generation DES. This study aimed to evaluate the long-term angiographic and intravascular ultrasound (IVUS) findings of the Firebird TM sirolimus eluting stent. METHODS: From December 2007 to March 2008, 15 patients with de novo lesions underwent PCI using the FirebirdTM stent. Angiography and IVUS were performed in all patients at 24 months of follow-up. The primary objective was to assess the late luminal loss by quantitative coronary angiography and in-stent percent volume obstruction by intravascular ultrasound (IVUS). RESULTS: Mean age was 57 ± 7.1 years, 87% were male and 27% were diabetics. The left anterior descending artery was the most frequently treated vessel (36%) and most of the lesions were B2/C type lesions (82%). At 24 months, late luminal loss was 0.17 ± 0.36 mm and target vessel revascularization was 6.6%. In-stent percent volume obstruction was 9.6 ± 4.6%. There were no cases of death, myocardial infarction or stent thrombosis. CONCLUSIONS: In this single center study in Brazil, the FirebirdTM stent showed good late outcomes. These findings, together with the available literature, provide further evidence for the use of the FirebirdTM stent in the daily clinical practice.

Inflamação sistêmica e dilatação do átrio esquerdo na hemodiálise crônica sem doença cardiovascular conhecida / Systemic inflammation and left atrium dilation in chronic hemodialysis without overt cardiovascular disease

Objetivo: Verificar a presença de associações entre inflamação sistêmica e dilatação do átrio esquerdo (AE), em pacientes sob hemodiálise (HD) de manutenção, sem doença cardiovascular (DCV) clinicamente manifesta. Métodos: Estudo observacional transversal em população sob HD (> 3 meses), excluindo-se pacientes com doença inflamatória crônica, infecções, neoplasias, instabilidade hemodinâmica, uso de drogas anti-inflamatórias, hiperparatireodismo, arritmias, valvopatia mitral e DCV prévia. Foram obtidas dosagens de proteína C reativa (PCR) e interleucina 6 (IL-6) e ecodopplercardiograma. Coeficientes de correlação foram determinados para avaliar as associações entre as variáveis. Resultados: Incluídos 58 pacientes (28 homens, idade 55 ± 15 anos), sob HD há 24 ± 16 meses, 45% hipertensos, 26% diabéticos, com medianas de PCR 5,1mg/ml e IL-6 6,1pg/ml. A PCR correlacionou-se, significativamente, com dimensão do AE (p= 0,040), volume indexado do AE (VIAE, p= 0,02) e onda E do fluxo mitral (p= 0,014). A IL-6, apesar da forte associação com a PCR (r= 0,75, p < 0,001), não se correlacionou com índices ecocardiográficos. Indivíduos no quartil superior da PCR tiveram VIAE, significativamente, maior do que os demais (42 ± 17 versus 32 ± 11, p= 0,015). Conclusão: Em indivíduos sob HD sem DCV prévia, houve associação entre elevação da PCR e aumento do AE. Os achados sugerem uma ligação entre processos fisiopatológicos relacionados à dilatação atrial esquerda e o estado inflamatório sistêmico de pacientes sob HD.

Objective: To verify associations between systemic infl ammation and left atrium (LA) dilatation in patients under maintenance hemodialysis (HD) without clinically overt cardiovascular disease (CVD). Methods: Observational cross-sectional study in population under HD (> 3 months), excluding patients with chronic infl ammatory disease, infections, neoplasia, hemodynamic instability, use of anti-infl ammatory drugs, hyperparathyroidism, arrhythmias, mitral valve disease and prior CVD. Measurements of C-reative protein (CRP) and interleukin 6 (IL-6), and echocardiograms were obtained. Correlation coeffi cients were determined to assess associations between variables. Results: The study comprised 58 patients (28 men, age 55 ± 15 years) under HD for 24 ± 16 months, 45% hypertensive, 26% diabetic, with median CRP 5.1 mg/ml and median IL-6 6.1 pg/ml. CRP was signifi cantly correlated with LA dimension (p= 0.040), indexed LA volume (p= 0.02), and mitral infl ow E-wave (p = 0.014). IL-6, despite the strong association with CRP (r= 0.75, p < 0.001), did not correlate with echocardiographic indexes. Individuals in the upper quartile of CRP had indexed LA volume significantly greater than the rest (42 ± 17 versus 32 ± 11, p= 0.015). Conclusion: In patients under HD without prior CVD, there was an association between elevated CRP and increased LA. The findings suggest a link between pathophysiological processes related to left atrial enlargement and systemic infl ammatory state of patients under HD.

Immunotoxicity of nanoparticles.

The interaction between NPs and immune system has been demonstrated, however, the data available are limited. Among all traits, i.s. hydrophilicity, lipophilicity, catalytic activity, composition, electronic structure, capacity to bind or coat surface species and solubility, the dimension, and consequently the surface area, seems to be the main factor that contribute to the interactions of NPs with biological tissues and immune system in particular. Certain NPs accumulate to regional lymph nodes, where they can be taken up and processed by dendritic cells, interact with self-proteins and, hence, modify their antigenicity and elicit altered immune responses and even autoimmunity. Other NPs may induce allergic sensitization, i.e. allergic contact dermatitis to Pd. In vitro studies demonstrated that NPs can modulate cytokine production toward Th1 (Pl, Pd, Ni, Co) or Th2 (Ti, mw and sw Carbon) production patterns. Some NPs have been linked to allergic sensitization, however, It is unlikely that NPs can act as a hapten inducing a specific IgE production, likely they can act as adjuvant and induce a specific pattern of cytokines, antibody and cells that favor allergic sensitization to environmental allergens. Furthermore, NPs demonstrated pro-inflammatory effects in the lung in experimental animal with increased expression on IL-1beta, MIP-1alpha, MCP-1, MIP-2, keratinocyte chemoattractant, TARC, GM-CSF, MIP-1alpha and activation of the stress-activated MAPKs p38 and JNKs. All considered, the available data suggest that through the elicitation of an oxidative stress mechanism, engineered NPs may contribute to pro-inflammatory disease processes in the lung, particularly allergy.

Controlling pain in the post-operative setting.

BACKGROUND AND AIMS: Post-operative pain (POP) is a form of acute, intense pain experienced in the period following surgery, whose adequate control is often problematic. This paper reviews determinants and characteristics of POP, together with rationale and current protocols for its management. DETERMINANTS/CONSEQUENCES OF POP: Main determinants of POP are the type of intervention and the disease motivating surgery, though other factors related to patient (age, pain threshold, socio-cultural factors, personality) and setting (pre-operative information, relationship with medical staff) may also influence its perception. POP control is essential to relieve suffering but also to prevent dangerous consequences on organ systems, e.g., reduced cough, atelectasis, increased myocardial oxygen consumption and ischemia, constipation, urinary retention, reduced musculoskeletal mobility and increased risk of deep venous thrombosis. MANAGEMENT OF POP: Constant assessment of pain intensity is recommended for optimal POP control. This is mostly achieved pharmacologically with monitoring of side-effects. Multi-modal analgesia is recommended, combining different drug classes, e.g., an opioid (morphine, pethidine, fentanyl, tramadol, codeine) with a non-opioid (NSAID; Cox-2 inhibitor), delivered through various routes, and including neuraxial use of local anesthetics (bupivacaine, ropivacaine) alone or in combination with other drugs, nerve blocks, antihyperalgesics (ketamine, dextromethorphan) and techniques such as patient-controlled analgesia (PCA) and pre-emptive analgesia. An efficient organization of pain services is also recommended. CONCLUSION: Acute post-surgical pain represents a crucial problem, but the multimodal therapeutic approach has enhanced the efficacy of pain-control while minimizing side-effects of each modality. Further improvement of POP control will necessarily involve better organization of pain services.

Expression and localisation of insulin receptor substrate 2 in normal intestine and colorectal tumours. Regulation by intestine-specific transcription factor CDX2.

BACKGROUND AND AIMS: Self-renewal and differentiation of intestinal epithelium is a tightly regulated process, whose perturbations are implicated in human colorectal tumourigenesis. The insulin/insulin-like growth factor (IGF) signalling pathway may play an important role in intestinal epithelium homeostasis. Insulin receptor substrate 2 (IRS2) is a poorly characterised component in this pathway. METHODS: Using complementary in vitro and in vivo human and murine models, expression (mRNA and protein levels), localisation (immunohistochemistry) and regulation of IRS2 were investigated in the normal intestine and colorectal tumours. In silico analysis of the human IRS2 promoter was performed together with reporter and chromatin immunoprecipitation assays. RESULTS: Significant IRS2 expression was detected in the intestine, with specific protein localisation in the villus region of the ileum and in the surface epithelium of the colon. In human HT29 and Caco2 cells, IRS2 mRNA levels increased with spontaneous and induced differentiation, together with CDX2 (caudal-related homeobox protein 2), P21 and KLF4 (Krüppel-like factor 4). Adenoviral infection with human CDX2 induced IRS2 expression in APC- (adenomatous polyposis coli) and beta-catenin-mutated cells. On the other hand, IRS2 downregulation was observed in differentiated enterocytes after adenoviral infection with short hairpin CDX2 (shCDX2), in the intestine of CDX2 heterozygous mice and in colorectal tumours of Apc(Min/+) and patients with familial adenomatous polyposis (FAP). The human IRS2 promoter region presents several CDX2-binding sites where CDX2 immunoprecipitated in vivo. IRS2 reporters were functionally activated via CDX2 and blocked via a dominant-negative CDX2 protein. CONCLUSIONS: Combining gain- and loss-of-function approaches, an intriguing scenario is presented whereby IRS2 is significantly expressed in the apical intestinal compartment and is directly controlled by CDX2 in normal intestine and tumours.

Pathological, clinical and prognostic characteristics of breast cancer in Central Sudan versus Northern Italy: implications for breast cancer in Africa.

AIMS: In patients of Black African ethnicity, breast cancer is reportedly characterized by aggressive, poorly differentiated phenotype(s). To highlight possible differences between breast cancer in indigenous sub-Saharan African and European patients, two breast cancer case series, from Central Sudan (Khartoum) and Northern Italy (Milan), were compared for clinicopathological characteristics, expression of oestrogen receptor (ER), progesterone receptor (PR), Her-2/neu, basal cytokeratin (CK) 5/6 and CK17, and breast cancer subtypes. METHODS AND RESULTS: After careful antigen retrieval, 114 and 138 consecutive formalin-fixed paraffin-embedded (FFPE) breast cancer cases from the Radiation and Isotope Centre (Khartoum) and from MultiMedica (Milan), respectively, were screened by immunohistochemistry for ER, PR, Her-2/neu, CK5/6 and CK17. Compared with the Italian patients, the Sudanese patients were younger (P < 0.0001) and their tumours were larger (P < 0.0001), more advanced in stage (P < 0.00001), higher grade (P < 0.00001) and more frequently positive for nodal metastases (P < 0.00001). ER expression varied between the two series (P < 0.0008), but no significant differences were found for PR (P < 0.32), combined hormone receptors (P < 0.12), Her-2/neu (P < 0.09), CK5/6 (P < 0.1), CK17 (P = 0.4), combined basal CK status (P = 1) or breast cancer subtypes (P = 0.12). CONCLUSION: The differences between the Sudanese and Italian breast cancer series reflect stage at diagnosis rather than intrinsic biological characteristics. This may have relevant implications for breast cancer prevention and treatment in Africa.

Immunotoxicity and sensitizing capacity of metal compounds depend on speciation.

Immunotoxicity of metal compounds is an issue of great importance due to the recent industrial application of metals with unknown toxicity on the immune system and the discovery of metal intermediary compounds not sufficiently studied yet. In this report we show results of our study on the immunotoxicity of the following metals: the Platinum group elements (Platinum, Palladium, Rhodium), Titanium and Arsenic. We applied functional and non functional assays and investigated both innate and adaptive immune systems, in particular, cell proliferation, cytokine production by PBMCs and O*2 production by neutrophils. We obtained the following results: only some Ti compounds (Titanocene, Ti ascorbate and Ti oxalate) show immunotoxicity. Trivalent As compounds (Sodium arsenite and tetraphenyl arsonium chloride) are more immunotoxic than the other investigated As compounds. Genotoxicity of Pt group compounds is in the following order: Pt > Rh > Pd. Immunotoxicity of Pt group compounds is in the following order: Pd > Pt > Rh. Lymphocytes and macrophages show a different reaction of neutrophils to metal toxicity. We can conclude that these studies show that metal immunotoxicity depends on speciation. In general speciation provides additional and often essential information in evaluating metal toxicity. However, there are many difficulties in applying speciation in investigating toxico-kinetic aspects to many metals, mainly due to the lack of information about the existence and significance of species and to the lack of analytical methods for measuring species in biological samples.

Analysis of extended genomic rearrangements in oncological research.

Screening for genomic rearrangements is a fundamental task in the genetic diagnosis of many inherited disorders including cancer-predisposing syndromes. Several methods were developed for analysis of structural genomic abnormalities, some are targeted to the analysis of one or few specific loci, others are designed to scan the whole genome. Locus-specific methods are used when the candidate loci responsible for the specific pathological condition are known. Whole-genome methods are used to discover loci bearing structural abnormalities when the disease-associated locus is unknown. Three main approaches have been employed for the analysis of locus-specific structural changes. The first two are based on probe hybridization and include cytogenetics and DNA blotting. The third approach is based on PCR amplification and includes microsatellite or single nucleotide polymorphism (SNP) genotyping, relative allele quantitation, real-time quantitative PCR, long PCR and multiplex PCR-based methods such as multiplex ligation-dependent probe amplification and the recently developed nonfluorescent multiplex PCR coupled to high-performance liquid chromatography analysis. Whole-genome methods include cytogenetic methods, array-comparative genomic hybridization, SNP array and other sequence-based methods. The goal of the present review is to provide an overview of the main features and advantages and limitations of methods for the screening of structural genomic abnormalities relevant to oncological research.

High prevalence of BRCA1 deletions in BRCAPRO-positive patients with high carrier probability.

Mutation screening of the BRCA1 and BRCA2 genes in probands with familial breast/ovarian cancer has been greatly improved by the multiplex ligation-dependent probe amplification (MLPA) assay able to evidence gene rearrangements not detectable by standard screening methods. However, no criteria for selection of cases to be submitted to the MLPA test have been reported yet. We used the BRCAPro software for the selection of familial breast/ovarian cancer probands investigated with the MLPA approach after negative BRCA1/2 conventional mutation screening. One hundred and seventy-seven probands were investigated for germline BRCA1/2 mutations after assessment of genetic risk using BRCAPro. Probands were classified as BRCAPro positive (n = 67) when the carrier probability (CP) was >10% and as BRCAPro negative (n = 110), when the CP was <10%. Conventional mutational analyses of the BRCA1/2 genes and, in one case, of p53 identified 22 pathogenetic germline mutations, 12 in BRCA1, 9 in BRCA2 and 1 in p53, in 22/177 (12.4%) probands. All the mutations except one were detected in BRCAPro-positive patients. In the 46 BRCAPro-positive cases that resulted negative by BRCA1/2 mutation, screening analysis of rearrangements within BRCA1/2 by MLPA was carried out. Three patients with a very high CP showed BRCA1 deletions, consisting of deletions of exons 1-2 in two probands and of exon 24 in the third proband. In one case, the exons 1-2 deletion was shown to cosegregate with disease in the family. No BRCA2 rearrangements were detected, but one patient showed the 1100delC of the CHEK2 gene, whose probe is present in the BRCA2 kit. In our series, the highest carrier detection rate of mutation screening plus MLPA analysis (52.3%) was in patients with a BRCAPro CP >50%.

Gastric adenomas: relationship between clinicopathological findings, Helicobacter pylori infection, APC mutations and COX-2 expression.

Gastric adenomas are rare neoplastic growths characterized by localized polypoid proliferations of dysplastic epithelium that tend to progress to infiltrating adenocarcinoma. Therefore, the identification of molecular markers that could reliably recognize adenomas at risk of progression is advocated in the clinical management. In this study we investigated, in a series of gastric adenoma specimens from an area at high risk of gastric cancer, the relationship between clinicopathological characteristics of adenoma and Helicobacter pylori infection, APC mutational status, and COX-2 and the down-stream enzyme mPGES1 expression. Helicobacter pylori infection, detected in 24%, and 33% by histology and PCR analyses, respectively, did not show any relationship with growth pattern, localization, size, dysplasia grade and presence of synchronous cancer. Pathogenetic mutations of MCR region (codons 1269-1589) of the APC gene were detected only in one case corresponding to a single, small size, low grade, H. pylori-negative adenoma. The expression of COX-2 largely matched that of mPGES(1). Both were overexpressed in 79% of cases showing a relationship with high-grade dysplasia, size >10 mm and presence of a synchronous carcinoma. In conclusion, COX-2 may play a key role in the development and progression of gastric adenoma and could be an attractive target in the management of gastric adenoma at major risk of cancer development.

Patterns of K-ras mutation in colorectal carcinomas from Iran and Italy (a Gruppo Oncologico dell'Italia Meridionale study): influence of microsatellite instability status and country of origin.

BACKGROUND: K-ras mutations are a key step in colorectal cancer progression. Such mutations have been widely studied in case series from Western countries but there are few data on the rate and spectrum of mutations in tumors from countries where the epidemiological features of the disease are different. PATIENTS AND METHODS: Tumor samples from 182 Iranian colorectal cancer patients (170 sporadic cases and 12 HNPCC cases) were screened for K-ras mutations at codons 12, 13 and 61 by sequencing analysis. The cases were also characterized for microsatellite instability at mononucleotide repeats by PCR and fragment analysis, and classified according to microsatellite instability status. The frequency and the spectrum of K-ras mutations were compared with those observed in a series of colorectal cancer patients from Italy. RESULTS: K-ras mutations were observed in 68/182 (37.4%) cases. Mutation frequencies were similar in HNPCC-associated, sporadic MSI-H and sporadic microsatellite-stable (MSS) tumors. However, the G13D substitution was more frequent in HNPCC (3/4, 75%) and sporadic MSI-H (7/11, 63.6%) tumors compared to sporadic MSS tumors (11/53, 20.4%) (P <0.01). Comparison of mutations in the two series from Iran and Italy showed a significantly higher frequency of G13D among Italian patients. CONCLUSIONS: While the frequency of K-ras mutations could be similar, the mutational spectrum could be differentially influenced by genetic and environmental factors.