E-cadherin and beta-catenin mRNA levels throughout colon cancer progression

Prognostic Significance of CDH1, FN1 and VIM for Early Recurrence in Patients with Colorectal Liver Metastasis After Liver Resection

Purpose

There are limited data on expression of epithelial–mesenchymal transition (EMT) markers in patients with colorectal liver metastases (CRLM). The study aim was to evaluate the expression and prognostic significance of E-cadherin (CDH1), fibronectin (FN1) and vimentin (VIM) in patients with CRLM after curative-intent liver resection.

Patients and Methods

Thirty patients with CRLM managed by curative-intent liver resection were included in this prospective pilot study. Blood samples, colorectal liver metastases and surrounding non-tumor liver tissue were collected. Expression of CDH1, FN1 and VIM was analyzed by quantitative real-time polymerase chain reaction. Expression in CRLM and non-tumor liver tissue was compared, while expression in serum was correlated with CRLM expression. One-year recurrence-free survival was compared between patients with low and high CDH1, FN1 and VIM expression.

Results

The expression of CDH1 was similar in CRLM and non-tumor liver tissues, while FN1 and VIM expression was significantly lower in metastatic tissue (P=0.003 and pP<0.001, respectively). Serum expression of CDH1 and VIM was detected in 66.7% and 93.3% of patients, respectively, while FN1 was not detected in any of the patients. The correlation of CDH1 and VIM expression between CRLM and serum was not statistically significant. Decreased CDH1 expression in CRLM and decreased VIM expression in serum were associated with early recurrence after surgical treatment of CRLM.

Conclusion

Lower expression of CDH1 in CRLM and lower serum expression of VIM were found to be associated with early recurrence after liver resection for CRLM.

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.

E-cadherin and NEDD9 expression in primary colorectal cancer, metastatic lymph nodes and liver metastases

In Croatia, colorectal cancer mortality rates in males are the third highest in Europe, after Hungary and Slovakia. The results for females rank Croatia in second place after Hungary. According to previous studies, the loss of E-cadherin expression and the higher expression of neural precursor cell-expressed developmentally downregulated 9 (NEDD9) are associated with a worse prognosis. The aim of the present study was to analyze the immunohistochemical expression of NEDD9 and E-cadherin as markers of metastatic potential using a tissue microarray. This retrospective study included 40 previously untreated patients, including 23 males and 17 females with a median age of 64.5 years (range 38–84), with colorectal cancer and synchronous liver metastases that underwent simultaneous colorectal and hepatic resection between January 1st 2006 and December 31st 2013, in the Clinical Hospital Center Sestre Milosrdnice (Zagreb, Croatia). The most frequent tumor stage was T3, while the most frequent nodal stage was N1. Microvascular invasion was present in 37.5% of patients, while perineural invasion was observed in 30% of patients. The immunohistochemical staining index of E-cadherin was highly positive in 87.5% samples of colorectal cancer, 67.7% of lymph nodes and 77.5% of liver metastases. In the primary tumor, highly positive NEDD9 expression was identified in 22.5% of patients. In lymph nodes, it was identified in 35.5% of patients, while in the liver, it was identified in 30% of patients. Significant positive correlations were observed between the percentage of positive lymph nodes and the immunohistochemical staining index of E-cadherin (ρ=0.372; P=0.039) and NEDD9 (ρ=0.451; P=0.011) in lymph nodes. After the conclusion of the study, 55% of the patients succumbed. No significant differences in survival rates were identified regarding the expression of E-cadherin and NEDD9 in the primary tumor, metastatic lymph nodes and liver metastases. Due to the small sample size and the negative results obtained, further research is required to implement these parameters as prognostic factors.

SMAR1 inhibits Wnt/β-catenin signaling and prevents colorectal cancer progression

Reduced expression of Scaffold/Matrix Attachment Region Binding Protein 1 (SMAR1) is associated with various cancers resulting in poor prognosis of the diseases. However, the precise underlying mechanism elucidating the loss of SMAR1 requires ongoing study. Here, we show that SMAR1 is highly downregulated during aberrant Wnt3a signaling due to proteasomal degradation and predicted poor prognosis of colorectal cancer. However, substitution mutation (Arginine and Lysine to Alanine) in the D-box elements of SMAR1 viz. "RCHL" and "RQRL" completely abrogated its proteasomal degradation despite Wnt3a activity. SMAR1 inhibited Wnt/β-catenin signaling by recruiting Histone deacetylase-5 to β-catenin promoter resulting in reduced cell migration and invasion. Consequently, reduced tumor sizes in in-vivo NOD-SCID mice were observed that strongly associated with suppression of β-catenin. However, loss of SMAR1 led to enriched H3K9 Acetylation in the β-catenin promoter that further increased Wnt/β-catenin signaling activities and enhanced colorectal cancer progression drastically. Using docking and isothermal titration calorimetric studies we show that small microbial peptides viz. AT-01C and AT-01D derived from Mycobacterium tuberculosis mask the D-box elements of SMAR1. These peptides stabilized SMAR1 expression that further inhibited metastatic SW480 colorectal cancer cell migration and invasion. Drastically reduced subcutaneous tumors were observed in in-vivo NOD-SCID mice upon administration of these peptides (25 mg/kg body weight) intraperitoneally. Taken together our structural studies, in-vitro and in-vivo results strongly suggest that the D-box elements of SMAR1 represent novel druggable targets, where the microbial peptides hold promise as novel colorectal cancer therapeutics.

Rab11 regulates E-cadherin expression and induces cell transformation in colorectal carcinoma

Background

In the process of epithelial mesenchymal transition EMT, the disassembly of junctional adhesion complexes such as E-cadherin is a remarkable sign during changes in cell morphology and polarity. However, E-cadherin expression is dynamic, and is regulated by the cellular endocytic system; it is also involved in cell signaling mechanisms. In this study, we investigated the role of E-cadherin in colorectal tumors and the relationship with recycling endosome protein Rab11 in colon cell transformation.

Methods

For tissue screening, the expressions of E-cadherin and Rab11 in colorectal tumors were identified by immunohistochemistry in 113 patients with colorectal carcinoma. For the in vitro cell experiment, GFP-tagged Rab11 plasmid was transfected into HT29 colon cells, E-cadherin expression and cell transformation were monitored by Western blot and confocal microscopy.

Results

In immunohistochemistry, the mean score of E-cadherin in tumor and normal tissues was 1.41 ± 0.06 and 1.08 ± 0.06 (p < 0.05). The mean score of Rab11 in tumor and normal tissues was 0.51 ± 0.05 and 0.18 ± 0.02 (p < 0.05). Synchronous overexpression of E-cadherin and Rab11 was noted in 74 patients (66.5%) with colorectal carcinoma. When GFP-tagged Rab11 plasmid was overexpressed in cultured colon cell line HT-29, the E-cadherin expression was up-regulated, and cell membrane protrusion was induced, which resulted in cell transformation and cell migration.

Conclusions

This study demonstrated the importance of the overexpression of Rab11 and E-cadherin in colorectal cancer. The results indicated that Rab11 together with E-cadherin might be potential markers for colorectal cancer progression and treatment.

Prognostic significance of Wnt-1, β-catenin and E-cadherin expression in advanced colorectal carcinoma

Wnt/β-catenin pathway plays an important role in initiation and progression of colorectal oncogenesis. The aim of this study was to determine expression and localization of E-cadherin, β-catenin and Wnt-1 proteins in colorectal tumors. Expression of β-catenin, E-cadherin and Wnt-1 was determined by immunohistochemistry on advanced colorectal cancers. Abnormal expression of E-cadherin, β-catenin, Wnt-1 was observed. Additionally, we revealed correlations between levels of studied proteins and histoclinical data. In multivariate analysis nuclear β-catenin, higher carcinoembryonic antigen serum level before treatment, female sex and tumor localized in colon or rectum were independent unfavorable prognostic factors. These findings support the hypothesis that Wnt/β-catenin pathway plays an important role in advanced colorectal carcinoma.

Synthetic (glyco-)peptides of the homophilic recognition domain of E-cadherin lead to increased E-cadherin mRNA synthesis and are inductors of cell differentiation in primary lung cancer cell lines

E-cadherin is one of the critical molecules involved in the metastatic process in many types of cancer. Once combined, E-cadherin exceeds the amount of membranous E-cadherin on the cellular surface by activation of intracellular signaling cascades. Studies on transformed keratinocytes of the HaCat cell line showed induction of differentiation by synthetical partial structures of the homophilic binding region of E-cadherin. The knowledge of effects in lung cancer cells is sparse. Therefore, the effects in primary lung cancer cell lines were investigated. Four primary lung cancer cell lines were incubated for 3, 6, 12, 15, 18, and 24h with synthetic partial structures (peptide and glycopeptide). The control substance was sodium butyrate. mRNA was isolated, and relative quantification of E-cadherin was performed using the Real-Time PCR. During the stimulation period, morphologic pictures were taken, and immunohistochemical staining of membranous E-cadherin was performed. Life/dead assays were used to display cell vitality. The intracellular E-cadherin mRNA amount was increased after incubation with the synthetic partial structures. Life/dead assays showed improved survival and integrated cell/cell bindings after stimulation with the partial structures. Increased cell mortality was revealed after sodium butyrate incubation. An effect mediated via E-cadherin on the cellular surface is proposed. The two synthetic partial structures of the homophilic binding region of E-cadherin increased the intracellular E-cadherin mRNA amount, cell-cell bindings, and survival of the tumor cells. Extracellular binding by synthetic partial structures to the binding region may have a beneficial influence on tumor progression in the metastatic process.

Zonula occludens-1, occludin, and E-cadherin protein expression in biliary tract cancers

The incidence of cholangiocarcinomas originating from intrahepatic and extrahepatic bile ducts, as well as of gallbladder carcinoma is increasing worldwide. The malignant transformation of biliary epithelia involves profound alterations of proteins in the intercellular junctions, among others zonula occludens-1 (ZO-1), occludin, and E-cadherin. Each plays important role in the maintenance of epithelial cell polarity and regulation of cell growth and differentiation. Our aim was to investigate ZO-1, occludin, and E-cadherin immunohistochemical reactions in tissue microarray blocks containing 57 normal and 62 neoplastic biliary tract samples. We demonstrated that the tight junction components ZO-1, occludin, and E-cadherin are downregulated in carcinomas arising from various compartments of the biliary tract (normal intrahepatic and extrahepatic bile ducts, gallbladder) as compared with their normal sites of origin. These results were confirmed by discriminant analysis yielding clear separation of the three normal sample groups from carcinomas in the corresponding locations.

De novo synthesis of {beta}-catenin via H-Ras and MEK regulates airway smooth muscle growth

beta-Catenin is a component of adherens junctions that also acts as a transcriptional coactivator when expressed in the nucleus. Growth factors are believed to regulate the nuclear expression of beta-catenin via inactivation of glycogen synthase kinase 3 (GSK-3) by phosphorylation, resulting in increased beta-catenin protein stability. Here, we report on a novel pathway that regulates the expression and nuclear presence of beta-catenin. In proliferating human airway smooth muscle cells, we observed increased expression of beta-catenin, which was required for proliferation. Interestingly, increased beta-catenin expression was accompanied by an increase in beta-catenin mRNA and was independent of beta-catenin liberation from the plasma membrane, suggesting a role for de novo synthesis. This was confirmed using actinomycin D and cycloheximide, which abrogated the induction and nuclear localization of beta-catenin protein. GSK-3 inhibition using SB216763 failed to regulate beta-catenin mRNA. However, expression of dominant negative H-Ras or pharmacological inhibition of MEK reduced serum and TGF-beta-induced beta-catenin mRNA and protein. Collectively, these data indicate that beta-catenin is an important signaling intermediate in airway smooth muscle growth and that its cellular accumulation and nuclear localization require de novo protein synthesis effected, in part, via H-Ras and MEK.-Gosens, R., Baarsma, H. A., Heijink, I. H., Oenema, T. A., Halayko, A. J., Meurs, H., Schmidt, M. De novo synthesis of beta-catenin via H-Ras and MEK regulates airway smooth muscle growth.

Novel nitro-oxy derivatives of celecoxib for the regulation of colon cancer cell growth

Celecoxib is a non-steroidal anti-inflammatory drug (NSAID) developed as a selective inhibitor of cyclooxygenase-2 (COX-2). Despite the associated cardiovascular toxicity risk, celecoxib has been found to be effective in reducing cancer risk in animal and human studies. In the present study the antiproliferative activity of novel nitro-oxy-methyl substituted analogues of celecoxib (NO-cel), potentially less cardiotoxic, has been investigated in vitro on human colon cancer cells and compared with action of the parent drug. Moreover, experiments were performed in order to evaluate whether COX-2 pharmacological inhibition may affect beta-catenin/E-cadherin signalling pathway. All the tested analogues of celecoxib exerted a significant antiproliferative activity on COX-2 positive HT-29 human colon cancer cells, being less effective on the COX-2 negative SW-480 human colon cancer cell line. In particular, the analogue displaying two nitro-oxy functions fully mimicked the known inhibitory properties of celecoxib, including inhibition of COX-2, as well as of ERK/MAPK and beta-catenin signalling pathways. Interestingly, the latter compound also elicited a strong reorganization of the beta-catenin/E-cadherin complex, which has been suggested to be relevant for colon carcinogenesis. On these premises, NO-cel analogues of celecoxib can represent promising colon cancer chemopreventive agents potentially able to affect colon cancer development.

The immunohistochemical expression of growth hormone-releasing hormone receptor splice variant 1 is a favorable prognostic marker in colorectal cancer

Hypothalamic growth hormone (GH)-releasing hormone (GHRH) regulates the release of GH from the pituitary gland. The receptors for GHRH (GHRH-R) are expressed predominantly in the pituitary. Recent evidence demonstrates that splice variants of the GHRH receptor are also expressed in several nonpituitary tissues, both normal and tumoral, as well as in cancer cell lines. The aim of this study was to investigate the expression of the splice variant 1 (SV-1) of GHRH-R in colorectal cancer (CRC). Seventy patients who underwent partial colectomy for CRC were enrolled in the study. Immunohistochemical expression of SV-1 was studied in paraffin-embedded sections of patient tumor tissue. A cytoplasmic supranuclear expression of SV-1 was observed in CRC as well as in the normal colon mucosa. Tumor grade and pathological stage were negatively correlated with expression of SV-1 (P = 0.012 and P = 0.013, respectively). CRCs metastatic to the liver showed a lower expression of SV-1 than did primary tumors, but this difference was not statistically significant. Kaplan-Meier and Cox univariate survival analyses indicated an improved survival time in patients with high SV-1 compared with those with low GHRH-R expression, but this difference was not statistically significant. The immunohistochemical expression of SV-1 seems to be a favorable prognostic factor in CRC.

Up-regulation and clinical relevance of novel helicase homologue DHX32 in colorectal cancer

Background

This study aimed to find novel biomarkers for colorectal cancer.

Methods

Fluorescent mRNA differential display PCR (DD-PCR) was used to screen the genes differentially expressed in colorectal cancer tissues and their adjacent tissues. The differentially expressed genes were confirmed by real-time PCR and then their clinical relevance (such as association with tumor location and lymph gland metastasis) was further investigated.

Results

We identified by DD-PCR a novel RNA helicase, DHX32, which showed higher expression in colorectal cancer tissues than their adjacent tissues, and this result was confirmed by real time RT-PCR. In addition, we found that the level of DHX32 gene expression in colorectal cancer was significantly associated with cancer location, lymph gland metastasis, cancer nodal status, differentiation grade, and Dukes, stage.

Conclusion

DHX32 may play an important role in the development of colorectal cancer and could serve as a novel biomarker for colorectal cancer after additional investigation.