Expression patterns of dysadherin and E-cadherin in lymph node metastases of colorectal carcinoma

Cadherins down-regulation: towards a better understanding of their relevance in colorectal cancer

The down-regulation of cadherin expression in colorectal cancer (CRC) has been widely studied. However, existing data on cadherin expression are highly variable and its relevance to CRC development has not been completely established. This review examines published studies on cadherins whose down-regulation has been already demonstrated in CRC, trying to establish a relationship with promoter methylation, the capacity to influence the Wnt / CTNNB1 (catenin beta 1, beta-catenin) signalling pathway and the clinical implications for disease outcome. Moreover, it also analyses factors that may explain data variability and highlights the importance of considering the altered subcellular localization of the examined cadherins. The results of this survey reveal that thirty of one hundred existing cadherins appear to be down-regulated in CRC. Among these, ten are cadherins, sixteen are protocadherins, equally divided between clustered and non clustered, and four are cadherin - related. These findings suggest that, to better define the role played by cadherin down-regulation in CRC pathogenesis, the expression of multiple rather than individual cadherins should be taken into account and further functional studies are necessary to clarify the relative ability of individual cadherins to inhibit CTNNB1 therefore acting as tumor suppressors.

Evaluation of the Effect of Foeniculum vulgare on the Expression of E-Cadherin, Dysadherin and Ki-67 in BALB/C Mice with 4T1 Model of Breast Cancer

Introduction: Breast cancer is described as a serious disease and one of the important factors of cancer-related deaths. Considering the drug resistance, special attention has been paid to natural compounds. This study aimed at evaluating the anti-metastatic activity of fennel in a breast cancer mouse model.Methods: A total of 28 adult female BALB/C mice were used in this study. Breast cancer was induced by subcutaneous injection of 4T1 cells in the right lower flank. The mice received fennel extracts daily via intraperitoneal injection for two weeks. Meanwhile, tumor volume was measured every day using calipers. After two weeks, each animal was anesthetized. The expression levels of ki-67 and dysadherin as tumor markers, as well as E-cadherin as a tumor suppressor, were measured in tumor tissue and ovary. Also the expression of her2 was measured in ovary.Results: Tumor size significantly decreased after nine days treatment of the fennel. Fennel treatment caused an increase in the ratio of the expression of E-cadherin to Ki-67 and dysadherin in the tumor tissues. On the other hand, the expression of Ki-67 and HER2 decreased in the ovary.Conclusion: Based on our findings, fennel has anti-tumor and anti-metastatic activities against aggressive cancers.

Curcumin Inhibits the Migration and Invasion of Non-Small-Cell Lung Cancer Cells Through Radiation-Induced Suppression of Epithelial-Mesenchymal Transition and Soluble E-Cadherin Expression

Radiotherapy has been reported to cause cancer metastasis. Thus, a new strategy for radiotherapy must be developed to avoid this side effect. A549 cells were exposed to radiation to induce an epithelial-mesenchymal transition (EMT) cell model. Real-time PCR and western blotting were used to detect mRNA and protein expression levels, and Transwell invasion and wound healing assays were used to detect cell migration and invasion. ELISA was used to detect soluble E-cadherin (sE-cad) secretion. siRNA was used to silence MMP9 expression. The results show that A549R cells exhibited an EMT phenotype with increased E-cadherin, N-cadherin, Snail, Slug, vimentin and Twist expression and decreased pan-keratin expression. sE-cad levels were increased in A549R cells and in the serum of NSCLC patients with distant metastasis. Exogenous sE-cad treatment and sE-cad overexpression promoted A549R and A549 cell migration and invasion. In contrast, blocking sE-cad attenuated A549 cell migration and invasion. Curcumin inhibited sE-cad expression and reversed EMT induced by radiation. Furthermore, curcumin suppressed sE-cad-enhanced A549 and A549R cell migration and invasion. Curcumin inhibited MMP9 expression, and silencing MMP9 suppressed sE-cad expression. Taken together, we found a nonclassic EMT phenomenon induced by radiation. Curcumin inhibits NSCLC migration and invasion by suppressing radiation-induced EMT and sE-cad expression by decreasing MMP9 expression.

A strategy for generating cancer-specific monoclonal antibodies to aberrant O-glycoproteins: identification of a novel dysadherin-Tn antibody

Successful application of potent antibody-based T-cell engaging immunotherapeutic strategies is currently limited mainly to hematological cancers. One major reason is the lack of well-characterized antigens on solid tumors with sufficient cancer specific expression. Aberrantly O-glycosylated proteins contain promising cancer-specific O-glycopeptide epitopes suitable for immunotherapeutic applications, but currently only few examples of such antibody epitopes have been identified. We previously showed that chimeric antigen receptor T-cells directed towards aberrantly O-glycosylated MUC1 can control malignant growth in a mouse model. Here, we present a discovery platform for the generation of cancer-specific monoclonal antibodies targeting aberrant O-glycoproteins. The strategy is based on cancer cell lines engineered to homogeneously express the truncated Tn O-glycoform, the so-called SimpleCells. We used SimpleCells of different cancer origin to elicit monoclonal antibodies with selectivity for aberrant O-glycoproteins. For validation we selected and characterized one monoclonal antibody (6C5) directed to a Tn-glycopeptide in dysadherin (FXYD5), known to be upregulated in cancer and promote metastasis. While dysadherin is widely expressed also in normal cells, we demonstrated that the 6C5 epitope is specifically expressed in cancer.

FXYD5 is a Marker for Poor Prognosis and a Potential Driver for Metastasis in Ovarian Carcinomas

Ovarian cancer (OC) is a leading cause of cancer mortality, but aside from a few well-studied mutations, very little is known about its underlying causes. As such, we performed survival analysis on ovarian copy number amplifications and gene expression datasets presented by The Cancer Genome Atlas in order to identify potential drivers and markers of aggressive OC. Additionally, two independent datasets from the Gene Expression Omnibus web platform were used to validate the identified markers. Based on our analysis, we identified FXYD5, a glycoprotein known to reduce cell adhesion, as a potential driver of metastasis and a significant predictor of mortality in OC. As a marker of poor outcome, the protein has effective antibodies against it for use in tissue arrays. FXYD5 bridges together a wide variety of cancers, including ovarian, breast cancer stage II, thyroid, colorectal, pancreatic, and head and neck cancers for metastasis studies.

Genomic and transcriptome analysis revealing an oncogenic functional module in meningiomas

OBJECT

Meningiomas are among the most common primary adult brain tumors. Although typically benign, roughly 2%-5% display malignant pathological features. The key molecular pathways involved in malignant transformation remain to be determined.

METHODS

Illumina expression microarrays were used to assess gene expression levels, and Illumina single-nucleotide polymorphism arrays were used to identify copy number variants in benign, atypical, and malignant meningiomas (19 tumors, including 4 malignant ones). The authors also reanalyzed 2 expression data sets generated on Affymetrix microarrays (n = 68, including 6 malignant ones; n = 56, including 3 malignant ones). A weighted gene coexpression network approach was used to identify coexpression modules associated with malignancy.

RESULTS

At the genomic level, malignant meningiomas had more chromosomal losses than atypical and benign meningiomas, with average length of 528, 203, and 34 megabases, respectively. Monosomic loss of chromosome 22 was confirmed to be one of the primary chromosomal level abnormalities in all subtypes of meningiomas. At the transcriptome level, the authors identified 23 coexpression modules from the weighted gene coexpression network. Gene functional enrichment analysis highlighted a module with 356 genes that was highly related to tumorigenesis. Four intramodular hubs within the module (GAB2, KLF2, ID1, and CTF1) were oncogenic in other cancers such as leukemia. A putative meningioma tumor suppressor MN1 was also identified in this module with differential expression between malignant and benign meningiomas.

CONCLUSIONS

The authors' genomic and transcriptome analysis of meningiomas provides novel insights into the molecular pathways involved in malignant transformation of meningiomas, with implications for molecular heterogeneity of the disease.

Alterations in dysadherin expression and F-actin reorganization: a possible mechanism of hypericin-mediated photodynamic therapy in colon adenocarcinoma cells

Dysadherin is a recently found anti-adhesion molecule, therefore detection and down regulation of its expression is promising in cancer treatment. The up-regulation of dysadherin contributes to colon cancer recurrence and metastasis. Dysadherin also has connections with cytoskeletal proteins and it can cause alterations in the organisation of filamentous actin (F-actin) in metastatic cancers. In this study, hypericin (HYP)-mediated photodynamic therapy (PDT) was performed in two different grade colon adenocarcinoma cell lines HT-29 (Grade I) and Caco-2 (Grade II). Cells were treated with 0.04, 0.08 or 0.15 μM HYP concentrations and irradiated with (4 J/cm(2)) fluorescent lamps. The effects of HYP was examined 16 and 24 h after the activation. We investigated for the first time the effect of HYP-mediated PDT on the expression of dysadherin and F-actin organisation. According to the results, HYP mediated PDT caused a decrease in gene expression and immunofluorescence staining of dysadherin and an increase in actin stress fibers and actin aggregates in HT-29 and Caco-2 cell lines. Besides, cytotoxicity, number of floating cells and apoptotic index changed depending on the cell type, HYP concentration and incubation time. We have demonstrated for the first time that dysadherin and F-actin could be target molecules for HYP-mediated PDT in HT-29 and Caco-2 colon cancer cell lines.

Diagnostic impact of promoter methylation and E-cadherin gene and protein expression levels in laryngeal carcinoma

Aim of the study

Inactivation of the tumor suppressor E-cadherin (CDH1) and its decreased expression is an important occurrence during carcinogenesis. Nevertheless, the relationship of CDH1 expression and the promoter methylation with laryngeal cancer cell aggressiveness is still unclear. The purpose of this study was to elucidate the gene and protein E-cadherin expression and the DNA methylation levels and to describe the correlations with morphological features in squamous cell laryngeal cancer.

Material and methods

The authors studied E-cadherin and the DNA methylation level in 86 cases to gain a further understanding of the clinicopathologic significance of analyzed parameters. The pathological evaluation included pTNM classification and the tumor front grading (TFG) criteria. Quantitative analysis of the amplified product in real time (qRT-PCR) for estimation of CDH1 mRNA was used. The methylation status was investigated by using methyl-specific polymerase chain reaction (MSP). The level of CDH1 protein expression by Western blot was determined.

Results

Downregulation of E-cadherin was found to be related to promoter methylation (p < 0.001). In tumors with the highest invasiveness according to TFG criteria the lowest E-cadherin gene and protein level in the study group was observed (p = 0.046 and p = 0.0002, respectively). In SCLC with muscle and cartilage invasion and disperse infiltration the lowest CDH1 gene and protein expression was noted (p = 0.0003 and p = 0.003 for deep invasion, p = 0.033 and p = 0.003 for multifocal infiltration, respectively).

Conclusions

The current findings suggest an association of E-cadherin tumor expression with progression of laryngeal cancer. CDH1 gene level may be an auxiliary molecular marker for advanced cases of laryngeal carcinoma; however, further studies are necessary.

Soluble E-cadherin: a critical oncogene modulating receptor tyrosine kinases, MAPK and PI3K/Akt/mTOR signaling

E-cadherin, a cell-cell adhesion glycoprotein, is frequently downregulated with tumorigenic progression. The extracellular domain of E-cadherin is cleaved by proteases to generate a soluble ectodomain fragment, termed sEcad, which is elevated in the urine or serum of cancer patients. In this study, we explored the functional role of sEcad in the progression of skin squamous cell carcinomas (SCCs). We found that full-length E-cadherin expression was decreased and sEcad increased in human clinical tumor samples as well as in ultraviolet (UV)-induced SCCs in mice. Interestingly, sEcad associated with members of the human epidermal growth factor receptor (HER) and insulin-like growth factor-1 (IGF-1R) family of receptors in human and UV-induced mouse tumors. Moreover, in both E-cadherin-positive (E-cadherin(+)) and -negative (E-cadherin(-)) cells in vitro, sEcad activated downstream mitogen-activated protein (MAP) kinase (MAPK) and phosphatidylinositol 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) signaling and enhanced tumor growth, motility and invasion, the latter via activation of matrix metalloproteinase-2 (MMP-2) and MMP-9. To this end, HER, PI3K or MEK inhibitors suppressed sEcad's tumorigenic effects, including proliferation, migration and invasion. Taken together, our data suggest that sEcad contributes to skin carcinogenesis via association with the HER/IGF-1R-family of receptors and subsequent activation of the MAPK and PI3K/Akt/mTOR pathways, thereby implicating sEcad as a putative therapeutic target in cutaneous SCCs.

Role of the recently identified dysadherin in E-cadherin adhesion molecule downregulation in head and neck cancer

Dysadherin is a cancer-related cell membrane glycoprotein, recently identified, playing an important role in tumor progression and metastasis. In the present minireview article, we are focusing on the role of dysadherin in E-cadherin downregulation, the various expression patterns of the molecule in head and neck cancer as well as its potential role as a molecular target for future applications in diagnosis, clinical routine and prognosis of the disease.

ER-α36 promotes the growth of SGC-7901 cells in nude mice

AIM: To observe the effect of ER-α36 on the growth of SGC-7901 cells in nude mice.

METHODS: Utilizing lentivirus technology, we developed SGC7901 cell lines stably expressing ER-α36 siRNA vector (SGC7901-Low36) and ER-α36 expression vector (SGC7901-High36). Unmanipulated SGC7901 cells were used as controls (SGC7901-Control). These cells were subcutaneously injected into the nude mice to form SGC7901 transplantable tumors. The size and weight of the tumors were measured. Nuclear division was observed after HE staining, and the expression of Ki67 and E-cadherin was detected by immunohistochemistry.

RESULTS: Transplantable tumors formed in all nude mice. From day 16 to day 30, tumor size was highest in the SGC7901-High36 group, followed by the SGC7901-Control group, and the SGC7901-Low36 group had the least tumor size. There were significant differences (all P < 0.05) in tumor size between any two groups. On day 30, tumor weight was significantly higher in the SGC7901-High36 group than in the SGC7901-Control and SGC7901-Low36 groups (2.58 g ± 0.014 g vs 1.32 g ± 0.0245 g, 0.471 g ± 0.021 g; both P < 0.05). The number of nuclear division phases was significantly higher in the SGC7901-High36 group than in the SGC7901-Control and SGC7901-Low36 groups (42.33 ± 6.33 vs 28.5 ± 0.35, 12.5 ± 2.5; both P < 0.05). The expression of Ki67 was significantly higher in the SGC7901-High36 group than in the SGC7901-Control and SGC7901-Low36 groups (86.35 ± 5.23 vs 65.44 ± 4.56, 18.25 ± 2.56; both P < 0.05). The expression of E-cadherin in tumors in the SGC7901-High36 group was hardly seen, significantly lower than that in the SGC7901-Control and SGC7901-High36 groups.

CONCLUSION: ER-α36 may play an important role in gastric cancer cell growth and proliferation. ER-α36 may target tumor cells through adhesion molecules to promote tumor invasion and metastasis.

FXYD5 (dysadherin) regulates the paracellular permeability in cultured kidney collecting duct cells

FXYD5 (dysadherin or RIC) is a member of the FXYD family of single-span transmembrane proteins associated with the Na(+)-K(+)-ATPase. Several studies have demonstrated enhanced expression of FXYD5 during metastasis and effects on cell adhesion and motility. The current study examines effects of FXYD5 on the paracellular permeability in the mouse kidney collecting duct cell line M1. Expressing FXYD5 in these cells leads to a large decrease in amiloride-insensitive transepithelial electrical resistance as well as increased permeability to 4-kDa dextran. Impairment of cell-cell contact was also demonstrated by staining cells for the tight and adherence junction markers zonula occludens-1 and β-catenin, respectively. This is further supported by large expansions of the interstitial spaces, visualized in electron microscope images. Expressing FXYD5 in M1 cells resulted in a decrease in N-glycosylation of β1 Na(+)-K(+)-ATPase, while silencing it in H1299 cells had an opposite effect. This may provide a mechanism for the above effects, since normal glycosylation of β1 plays an important role in cell-cell contact formation (Vagin O, Tokhtaeva E, Sachs G. J Biol Chem 281: 39573-39587, 2006).

Physiology and pathophysiology of selectins, integrins, and IgSF cell adhesion molecules focusing on inflammation. A paradigm model on infectious endocarditis

The development of adhesion bonds, either among cells or among cells and components of the extracellular matrix, is a crucial process. These interactions are mediated by some molecules collectively known as adhesion molecules (CAMs). CAMs are ubiquitously expressed proteins playing a central role in controlling cell migration, proliferation, survival, and apoptosis. Besides their key function in physiological maintenance of tissue integrity, CAMs play an eminent role in various pathological processes such as cardiovascular disorders, atherogenesis, atherosclerotic plaque progression and regulation of the inflammatory response. CAMs such as selectins, integrins, and immunoglobulin superfamily take part in interactions between leukocyte and vascular endothelium (leukocyte rolling, arrest, firm adhesion, migration). Experimental data and pathologic observations support the assumption that pathogenic microorganisms attach to vascular endothelial cells or sites of vascular injury initiating intravascular infections. In this review a paradigm focusing on cell adhesion molecules pathophysiology and infective endocarditis development is given.

HEF1, a novel target of Wnt signaling, promotes colonic cell migration and cancer progression

Misregulation of the canonical Wnt/β-catenin pathway and aberrant activation of Wnt signaling target genes are common in colorectal cancer (CRC) and contribute to cancer progression. Altered expression of human enhancer of filamentation 1 (HEF1; also known as NEDD9 or Cas-L) has been implicated in progression of melanoma, breast, and CRC. However, the regulation of HEF1 and the role of HEF1 in CRC tumorigenesis are not fully understood. We here identify HEF1 as a novel Wnt signaling target. The expression of HEF1 was upregulated by Wnt-3a, β-catenin, and Dvl2 in a dose-dependent manner, and was suppressed following β-catenin downregulation by shRNA. In addition, elevated HEF1 mRNA and protein levels were observed in CRC cell lines and primary tumor tissues, as well as in the colon and adenoma polyps of Apc(Min/+) mice. Moreover, HEF1 levels in human colorectal tumor tissues increased with the tumor grade. Chromatin immunoprecipitation (ChIP) assays and promoter analyses revealed three functional T-cell factor (TCF)-binding sites in the promoter of HEF1 responsible for HEF1 induction by Wnt signaling. Ectopic expression of HEF1 increased cell proliferation and colony formation, while downregulation of HEF1 in SW480 cells by shRNA had the opposite effects and inhibited the xenograft tumor growth. Furthermore, overexpression of HEF1 in SW480 cells promoted cell migration and invasion. Together, our results determined a novel role of HEF1 as a mediator of the canonical Wnt/β-catenin signaling pathway for cell proliferation, migration, and tumorigenesis, as well as an important player in colorectal tumorigenesis and progression. HEF1 may represent an attractive candidate for drug targeting in CRC.

Significance of dysadherin and E-cadherin expression in differentiated-type gastric carcinoma with submucosal invasion

Dysadherin is a cancer-associated cell membrane glycoprotein that down-regulates E-cadherin and plays important roles in tumor progression and metastasis. Differentiated-type gastric carcinoma can be classified into 2 histologic subtypes according to the presence of poorly differentiated components: a mixed type (differentiated carcinoma with poorly differentiated components) and a pure type (purely differentiated-type adenocarcinoma). We studied the clinicopathologic features of 318 cases of differentiated-type gastric carcinoma with submucosal invasion and evaluated the immunohistochemical expression of dysadherin and E-cadherin. We also evaluated 46 cases of metastatic lymph nodes. Tumors with combined dysadherin-positive (≥50%) expression and E-cadherin-negative (<50%) expression had significantly higher proportions of the moderately differentiated type, deeper submucosal invasion, positivity of lymphatic permeation, and positivity of lymph node metastasis than tumors with other combinations of dysadherin and E-cadherin expression (P = .0009, P = .0015, P = .0273, and P = .0187, respectively). Moreover, the frequency of dysadherin-positive (≥50%) expression was higher in the mixed type (60.3%) than in the pure type (12.4%) (P < .0001), whereas the frequency of E-cadherin-negative (<50%) expression was higher in the mixed type (84.5%) than in the pure type (50.5%) (P < .0001). The frequency of dysadherin expression in the metastatic lymph nodes (80.4%) was significantly higher than that in the primary tumors (45.7%) (P = .001). Dysadherin-positive (≥50%) expression and E-cadherin-negative (<50%) expression may be correlated with the mixed type. Combined dysadherin-positive (≥50%) expression and E-cadherin-negative (<50%) expression may be valuable information for predicting aggressive tumor behavior.

Site-dependent E-cadherin cleavage and nuclear translocation in a metastatic colorectal cancer model

Metastases are frequently found during colorectal cancer diagnoses and are the main determinants of clinical outcome. The lack of reliable models of metastases has precluded their mechanistic understanding and our capacity to improve outcome. We studied the effect of E-cadherin and Snail1 expression on metastagenesis in a colorectal cancer model. We microinjected SW480-ADH human colorectal cancer cells, transfected with an empty vector (Mock) or overexpressing Snail1 (Snail1(OE)) or E-cadherin (E-cadherin(OE)), in the ceca of nude mice (eight per group) and analyzed tumor growth, dissemination, and Snail1, E-cadherin, β-catenin, and Presenilin1 (PS1) expression in local tumors and/or metastatic foci. Snail1(OE) cells disseminated only to lymph nodes, whereas Mock or E-cadherin(OE) cells spread to lymph nodes and peritoneums. Peritoneal tumor foci developed by E-cadherin(OE) cells presented an increase in E-cadherin proteolysis and nuclear translocation, and enhanced expression of proteolytically active PS1, which was linked to increased tumor growth and shortened mouse survival. Interestingly, local and lymph node tumors in mice bearing E-cadherin(OE) cells overexpressed E-cadherin, but they did not show E-cadherin proteolysis or nuclear translocation. Remarkably, E-cadherin nuclear translocation and enhanced expression of active PS1 were found in a patient with colorectal signet-ring cell carcinoma. In conclusion, we have established a colorectal cancer metastasis model in which E-cadherin proteolyis and nuclear translocation associates with aggressive foci growth only in the peritoneal microenvironment.

Dynamic changes in E-cadherin gene promoter methylation during metastatic progression in papillary thyroid cancer

Thyroid cancer cells undergo epithelial to mesenchymal transition (EMT) in the invasive front of tumor. To determine whether the mesenchymal feature of invasive cancer cells is maintained in metastatic sites, we examined E-cadherin methylation and E-cadherin expression in 66 papillary thyroid cancer (PTC) samples and in 34 corresponding lymph node metastases (LNM). Relationships between E-cadherin and cell motility were evaluated using thyroid cancer cell lines. Hypermethylation of the E-cadherin gene promoter was detected in 39.3% of the PTCs, and loss of E-cadherin expression correlated with lymphocytic infiltration, extrathyroidal invasion and the presence of metastases. Comparing primary PTCs to the corresponding LNM, E-cadherin methylation status was identical in 60% of the cases. The switch in E-cadherin promoter status from unmethylated in PTCs to hypermethylated in LNM was detected in 5%; and from hypermethylatated in PTCs to unmethylated in LNM in 35%. Loss of epigenetic silencing in LNM was associated with a gain of E-cadherin expression. Hypermethylation of the E-cadherin gene promoter was detected in thyroid cancer cell lines with mesenchymal-like morphology. Loss of E-cadherin expression in these cells correlated with high migratory ability. Inhibition of RAS/ERK or PI3K/AKT signaling decreased the migratory ability of these cells but did not induce E-cadherin expression. In the cells with epithelial-like morphology, treatments with phorbol-ester or tumor necrosis factor (TNF)-α resulted in translocation of membranous E-cadherin to the cytoplasm and induction of migration. E-cadherin promoter methylation status and E-cadherin expression were not affected by TNF. Demethylating agents induced apoptosis in the mesenchymal-like cells but had no effect on E-cadherin expression or on migratory ability. Together, dynamic changes in E-cadherin methylation occur during metastatic progression in thyroid cancer. Epigenetic mechanisms and TNF-inducible signaling independently contribute to the regulation of E-cadherin expression and localization. These mechanisms may play a role in the induction of EMT in primary tumors and in the conversion from the mesenchymal to the epithelial phenotype in metastases.

Parathormone and 1,25(OH)2D3 but not 25(OH)D3 serum levels, in an inverse correlation, reveal an association with advanced stages of colorectal cancer

Experimental, epidemiologic, and clinical trial data indicate the antineoplastic effects of calcium and vitamin D in large-bowel neoplasia. The aim of this study was to determine serum levels of vitamin D metabolites and parathormone (PTH) in patients with colorectal cancer (CRC) and to extract conclusions comparing their different levels in serum with healthy individuals. Group 1 (cancer patients) was consisted of 140 patients with CRC with clinical stages Duke's A: 12, B: 52, C: 62, and D: 14. Serum levels of 25(OH)D(3), 1,25(OH)(2)D(3), and PTH were determined in all patients. The findings are: (a) No significant difference was found in the serum levels of 25(OH)D(3) in each Duke's clinical stage in cancer patients, (b) serum 1,25(OH)(2)D(3) levels decreased with advanced cancer stages, and (c) serum levels of PTH showed a corresponding increase. Low serum levels of 1,25(OH)(2)D(3) on one hand and increased levels of PTH in patients with CRC on the other might be strongly related to the carcinogenetic process.

FXYD5 modulates Na+ absorption and is increased in cystic fibrosis airway epithelia

FXYD5, also known as dysadherin, belongs to a family of tissue-specific regulators of the Na(+)-K(+)-ATPase. We determined the kinetic effects of FXYD5 on Na(+)-K(+)-ATPase pump activity in stably transfected Madin-Darby canine kidney cells. FXYD5 significantly increased the apparent affinity for Na(+) twofold and decreased the apparent affinity for K(+) by 60% with a twofold increase in V(max) of K(+), a pattern that would increase activity and Na(+) removal from the cell. To test the effect of increased Na(+) uptake on FXYD5 expression, we analyzed Madin-Darby canine kidney cells stably transfected with an inducible vector expressing all three subunits of the epithelial Na(+) channel (ENaC). Na(+)-K(+)-ATPase activity increased sixfold after 48-h ENaC induction, but FXYD5 expression decreased 75%. FXYD5 expression was also decreased in lung epithelia from mice that overexpress ENaC, suggesting that chronic Na(+) absorption by itself downregulates epithelial FXYD5 expression. Patients with cystic fibrosis (CF) display ENaC-mediated hyperabsorption of Na(+) in the airways, accompanied by increased Na(+)-K(+)-ATPase activity. However, FXYD5 was significantly increased in the lungs and nasal epithelium of CF mice as assessed by RT-PCR, immunohistochemistry, and immunoblot analysis (P < 0.001). FXYD5 was also upregulated in nasal scrapings from human CF patients compared with controls (P < 0.02). Treatment of human tracheal epithelial cells with a CFTR inhibitor (I-172) confirmed that loss of CFTR function correlated with increased FXYD5 expression (P < 0.001), which was abrogated by an inhibitor of NF-kappaB. Thus FXYD5 is upregulated in CF epithelia, and this change may exacerbate the Na(+) hyperabsorption and surface liquid dehydration observed in CF airway epithelia.

Differential expression of dysadherin in papillary thyroid carcinoma and microcarcinoma: correlation with E-cadherin

Dysadherin is a novel glycoprotein, with an anti-cell-cell adhesion function. The aim of the present study was to examine the expression of dysadherin in thyroid papillary microcarcinoma (PMC), to associate it with the expression of E-cadherin and to investigate whether there are differences with papillary carcinoma (PC). A statistically significant difference in dysadherin and E-cadherin expression between PC and PMC and a negative correlation between E-cadherin and dysadherin expression regardless of tumor size were noted. Based on these findings it is hypothesized that retained cell-cell adhesion, through maintenance of the E-cadherin adhesion system, in PMC prevents neoplastic cells from dissociating easily from each other and metastasizing. Increased dysadherin expression is possibly one of the post-transcriptional mechanisms responsible for E-cadherin downregulation in thyroid papillary neoplasia.

A new concept of melanocytic neoplasia pathogenesis based on the phenotype of common acquired nevi

Common melanocytic nevi are ubiquitous lesions which in some cases constitute a risk factor for the development of melanoma. To date, despite long term research there are no known molecular hallmarks for nevus development. We have observed that common acquired nevi excised from the same individual share remarkable similarity in their microscopic appearance and in the immunohistochemical expression of E-cadherin. Based on these observations, we hypothesize that all melanocytes are genetically similar in the same individual and changes predisposing to neoplasia are a global melanocytic event characteristic for each person and propose a microgenomics/proteomics approach to test this hypothesis.

Dysadherin: a new player in cancer progression

Dysadherin is a cancer-associated cell membrane glycoprotein that promotes experimental cancer metastasis. Here we review recent work that has provided insights into possible mechanisms of action of this newly recognized player in the cancer progression process. Dysadherin modulates cell phenotype in a number of ways, including down-regulation of E-cadherin-mediated cell adhesion, and up-regulation of chemokine production. In this way, expression of dysadherin in a tumor can influence both the tumor cell itself and the stromal compartment, so as to create conditions that are more permissive for metastatic spread. Dysadherin expression is also an independent prognostic indicator of metastasis and survival for many different types of human cancer. Thus, dysadherin may represent a new molecular target for the visualization, prevention or treatment of advanced cancer.

In breast carcinoma dysadherin expression is correlated with invasiveness but not with E-cadherin

Reduction/loss of E-cadherin is associated with the development and progression of many epithelial tumours. Dysadherin, recently characterised by members of our research team, has an anti-cell–cell adhesion function and downregulates E-cadherin in a post-transcriptional manner. The aim of the present study was to study the role of dysadherin in breast cancer progression, in association with the E-cadherin expression and the histological type. We have selected ductal carcinoma, which is by far the most common type and lobular carcinoma, which has a distinctive microscopic appearance. Dysadherin and E-cadherin expression was examined immunohistochemically in 70 invasive ductal carcinomas, no special type (NST), and 30 invasive lobular carcinomas, with their adjacent in situ components. In ductal as well as in lobular carcinoma dysadherin was expressed only in the invasive and not in the in situ component, and this expression was independent of the E-cadherin expression. Specifically, all 10 (100%) Grade 1, 37out of 45(82.2%) Grade 2 and six out of 15 (40%) Grade 3 invasive ductal carcinomas showed preserved E-cadherin expression, while ‘positive dysadherin expression’ was found in six out of 10 (60%) Grade 1, 34 out of 45(75.5%) Grade 2 and all 15 (100%) Grade 3 neoplasms. None of the 30 infiltrating lobular carcinomas showed preserved E-cadherin expression, while all the 30 infiltrating lobular carcinomas exhibited ‘positive dysadherin expression’. Dysadherin may play an important role in breast cancer progression by promoting invasion and, particularly in lobular carcinomas, it might also be used as a marker of invasion.

Expression of adhesion molecules during normal pregnancy

We review the available information regarding the role of adhesive molecules as potential participants in the complex events of fertilization, embryogenesis, implantation and placentation. Studies that specifically relate to the expression and modulation of adhesive molecules in fertilization, embryogenesis, and implantation have been identified in the literature and by Medline searches. Cell-cell and cell-extracellular matrix interactions play a critical role in various developmental processes and in the cascade of events that lead to implantation and to the normal development of the fetus during pregnancy. Adhesion molecules influence, directly or indirectly, numerous aspects of cell behaviour, cell migration, cell growth, cell survival, cell proliferation, angiogenesis, invasion and metastasis.