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Epithelial-mesenchymal transition (EMT) process has a central role in tumor progression and metastases. Loss of cell-to-cell adhesiveness is a key step in EMT. In particular, E-cadherin and β-catenin, components of the adherens junctions, play a strategic role. Accumulation of β-catenin at cytoplasmic level following adherens junctions disruption, induces its translocation into the nucleus, where it binds to members of the TCF/LEF family of transcription factors. In particular, Lymphoid Enhancer-Binding factor 1 (LEF1) product can target genes involved in EMT. The aim of the present study was to evaluate the influence of CDH1 and CTNNB1 genes, coding for E-cadherin and β-catenin respectively and LEF1 in a sample study of 140 Italian patients affected by colorectal cancer. An association study between four single nucleotide polymorphisms (rs11865026, rs11642413, rs13689, and rs10431923) of CDH1 and the disease did not provide statistically significant results. The gene expression analysis carried out for CDH1, CTNNB1 and LEF1 in 54 paired specimens from 27 patients provided evidence of a reduced expression of the first two in cancer tissues. We believe there may be a sort of cross regulation between the products of these two genes which closely interact in EMT activation and that such hypothesis should be further investigated in a greater number of cases.

Research has widely supported the efficacy of screening for colorectal cancer in reducing mortality. A blood-based assay potentially represents a more accessible early detection tool for the identification of solid tumor cells originating from a primary tumor site in the body. We demonstrate a relatively easy and highly reproducible technique for the detection of mRNA expression of genes as markers of malignancy in blood samples of patients with colon cancer. The present study aims to identify a set of specific mRNAs expressed in epithelial cells but not in blood cells, which may be useful as markers for early detection of circulating colon cancer cells by a simple, qualitative RT-PCR assay following semi-automated RNA extraction from peripheral blood samples. Our approach includes a systematic search for candidate markers using digital differential display, search on UniGene colon EST libraries and analysis of published data on colon cancer gene expression. A final list included the following genes: bone morphogenetic protein 4 (BMP4), cyclin D (CycD), family with sequence similarity 3, member D (FAM3D), gastrin (GAS), glycoprotein A33 transmembrane (GPA33), glutathione peroxidase 2 gastrointestinal (GPX2), galactoside-binding, soluble, 4 (galectin 4) (LGALS4), non-SMC, structural maintenance of chromosomes, element 1 protein (NSE1), tumor-associated calcium signal transducer 1 (TACSTD1), telomerase reverse transcriptase (hTERT), trefoil factor 3 intestinal (TFF3), transmembrane 4 superfamily member 3 (TM4SF3), UDP glycosyltransferase 1 family, polypeptide A9 (UGT1A9), villin 1 (VIL1), and the novel gene FLJ20127. The mRNA expression of these genes was evaluated in a pool of 16 samples from subjects diagnosed with colon cancer and from 16 normal-controls. We observed expression in 13 of the 15 investigated genes from the blood samples of the vast majority of patients considered, but also in a certain percentage of the controls (from 14.3 to 100%). This finding confirms that the extreme sensitivity of RT-PCR is able to detect minimal amounts of mRNA expressed in a non tissue-specific manner ('illegitimate transcription'). On the contrary, NSE1 and GAS mRNAs were not detected either in patient or in control blood samples; however, they were abundantly expressed in normal and cancerous colon mucosa, encouraging further search for useful markers able to detect epithelial cells in peripheral blood.

Adenomatous polyposis coli (APC) mutation is the most common genetic change in sporadic colorectal cancer (CRC). Although deregulations of miRNAs have been frequently reported in this malignancy, APC-regulated miRNAs have not been extensively documented. Here, by using an APC-inducible cell line and array analysis, we identified a total of 26 deregulated miRNAs. Among them, members of miR-17-92 cluster were dramatically inhibited by APC and induced by enforced expression of β-catenin. Furthermore, we demonstrate that activated β-catenin resulted from APC loss binds to and activates the miR-17-92 promoter. Notably, enforced expression of miR-19a overrides APC tumor suppressor activity, and knockdown of miR-19a in cancer cells with compromised APC function reduced their aggressive features in vitro. Finally, we observed that expression of miR-19a significantly correlates with β-catenin levels in colorectal cancer specimens, and it is associated to the aggressive stage of tumor progression. Thus, our study reveals that miR-17-92 cluster is directly regulated by APC/β-catenin pathway and could be a potential therapeutic target in colon cancers with aberrant APC/β-catenin signaling.Oncogene advance online publication, 25 January 2016; doi:10.1038/onc.2015.522.

Relatively little is known about the biocompatibility of the soldered or laser-welded joints of dental appliances. We investigated the reaction of human gingival fibroblasts cultured in vitro in direct contact with samples of soldered and laser-welded joints from orthodontic lingual arches. Contrast phase light microscopy was used to evaluate cell adhesion, morphology and proliferation after 6 and 24h and after 7 and 16 days. Scanning electron microscopy (SEM) was performed at 16 days. Our in vitro findings provide evidence that laser-welded orthodontic appliances have superior fibroblast biocompatibility.

Background The ATP-binding cassette transporter B1 (ABCB1) gene codes for a membrane efflux pump localized in epithelial cells. Together with other Permeability-glycoproteins in the small and large intestine, its product represents a barrier against xenobiotics, bacterial toxins, drugs and other substances introduced with diet, including carcinogens. The aim of this investigation was to verify the possible contribution of ABCB1 single nucleotide polymorphisms (SNPs) to the genetic risk of colorectal cancer (CRC). Results DNA obtained from the peripheral blood of 98 CRC patients and 100 healthy controls was genotyped for the three selected SNPs: 1236C > T (rs1128503), 2677G > T/A (rs2032582), and 3435C > T (rs1045642). Molecular data were analyzed to asses allele and haplotype association with CRC. No evidence of an association between ABCB1 alleles and CRC occurrence as a whole was found. However, ABCB1 showed either association with carcinoma of the sigmoid colon, and appeared able to influence the sex ratio among CRC patients. These two effects seemed to act independently based on multivariate analysis. We showed that ABCB1 polymorphisms were able to influence CRC susceptibility related to tumor localization and patient gender. Conclusions We suggest that sensitivity to undetermined risk factors could depend on the genetic background of ABCB1 locus, with a mechanism that also depends on patient gender. Electronic supplementary material The online version of this article (doi:10.1186/s12929-014-0089-8) contains supplementary material, which is available to authorized users.

The risk of colorectal cancer (CRC) may be influenced by aberrant DNA methylation and altered nucleotide synthesis and repair, possibly caused by impaired dietary folate intake as well as by polymorphic variants in one-carbon metabolism genes. A case–control study using seventy-one CRC patients and eighty unrelated healthy controls was carried out to assess the genetic association of fifteen SNP and one insertion in nine genes belonging to the folate pathway. Polymorphism selection was based on literature data, and included those which have a known or suspected functional impact on cancer and missense polymorphisms that are most likely to alter protein function. Genotyping was performed by real-time PCR and PCR followed by restriction analysis. The likelihood ratio statistic indicated that most of the polymorphisms were not associated with the risk of CRC. However, an increased risk of CRC was observed for two variant alleles of SNP mapping on the transcobalamin 2 gene (TCN2): C776G (rs1801198) and c.1026-394T>G (rs7286680). Considering the crucial biological function played by one-carbon metabolism genes, further investigations with larger cohorts of CRC patients are needed in order to confirm our preliminary results. These preliminary results indicate that TCN2 polymorphisms can be a susceptibility factor for CRC.

Epidermal growth factor receptor (EGFR) family members (EGFR, HER2, HER3 and HER4) have been extensively investigated for its possible involvement in cancer development and progression. In colorectal cancer (CRC) EGFR family has been found frequently over-expressed, thus therapy targeting EGFR has been developed. Interestingly, it has been observed that genetic variants in these receptors may alter the therapeutic efficacy of EGFR inhibitors. Polymorphic variants in members of the EGFR family could influence different biologic activities, such as ligands affinity, dimerization efficiency, kinase activity, expression levels, with a consequent impact in signalling pathways and cell behaviour. This study aimed to verify whether single nucleotide polymorphisms (SNPs) of EGFR family members could represent susceptibility factors able to influence the risk to develop CRC. Peripheral blood of 70 Italian colon cancer patients and 72 healthy controls was used as a source of genomic DNA to investigate EGFR, HER2 and HER3 common non-synonymous SNPs. Genetic association tests were performed to verify a possible relationship with CRC. Evidence of genotype association was found for the R521K EGFR polymorphism under a dominant mode of inheritance (Mid-P=0.031). Genotypes with the variant allele of EGFR R521K SNP confer a risk reduction to develop CRC.

Normal branching development is dependent on the correlation between cells and extracellular matrix. In this interaction glycosaminoglycans, cytokines and growth factors play a fundamental role. In order to verify the distribution and influence of extracellular matrix and related enzymes on chick embryo lung development, 6 day-old whole lungs were maintained in vitro with testicular hyaluronidase, beta-N-acetyl-D-glucosaminidase and chondrotinase ABC or in linkage with apical, medial and caudal lung regions of 6-day development before and after enzyme treatment. In a separate lung region beta-N-acetyl-D-glucosaminidase and hyaluronidase were determined. Our data show that the whole lung cultures increase bronchial branching development when the medial region is admixed separately, while the separate apical or caudal regions or apical combined with caudal region do not affect bronchial branching development. The enzyme treatment of medial region prevents the branching development in associated whole lung. The bronchial branching development of whole lung cultured in medium containing the enzymes related to glycosaminoglycans turnover is significantly altered. In conclusion, these data show that the different influence of separate apical, medial, caudal lung regions on bronchial branching development is related to the extracellular matrix composition.

Alkaline phosphatases (ALPs) are a family of cell surface glycoproteins that catalyze the hydrolysis of phosphomonoesters with release of inorganic phosphate. Liver/bone/kidney (L/B/K) ALP participates in bone mineralization, but its other physiological and pathological functions remain obscure. In human osteosarcoma, an inverse relationship has been found between cellular L/B/K ALP expression and aggressiveness. To explore this relationship, we employed cDNA microarray technology to characterize and compare the gene expression profile of two U-2 OS osteosarcoma clones with high L/B/K ALP activity (U-2/ALP28 and U-2/ALP40) and one with contrasting characteristics (U-2/ALP23). We identified 79 differentially expressed genes (58 upregulated in U-2/ALP28 and U-2/ALP40 compared to U-2/ALP23). Using GenMAPP/MAPPFinder, we highlighted nine functional groups strictly related to high L/B/K ALP activity, including microtubule-based movement and cell adhesion groups, two functions well related to tumor invasiveness. Notably, cadherin 13 ( CDH13 ) and caveolin 1 ( CAV1 ) genes were upregulated in our cells. Since these two genes are involved in cell–cell adhesion and cell growth, their co-expression with L/B/K ALP could help explain the lower levels of malignancy found in osteosarcoma cells with high L/B/K ALP activity. Although functional studies are needed to better define the role of CDH13 and CAV1 in the malignant behavior of osteosarcoma cells, the data presented here provide an aid to understanding the biological functions of L/B/K ALP in bone tumors.