Low E-cadherin Expression Research Articles

Relationship between LSD1 expression and E-cadherin expression in prostate cancer

To investigate the relationship between the expression of LSD1 and E-cadherin in prostate cancer and their prognostic significance. The expression of LSD1 and E-cadherin in prostate cancer was detected using immunohistochemistry, and the relationship between the expressions of these two molecules was analyzed by correlation analysis. Furthermore, LNCap cell line was treated with Pargyline (an inhibitor of LSD1), and Western blot was used to analyze LSD1 and E-cadherin expression. LSD1 expression increased significantly in prostate cancer specimens compared with benign prostatic hyperplasia (P < 0.05). Further analysis testified that LSD1 expression was positively correlated with higher Gleason Score, distant metastases, and poor prognosis (P < 0.05). Nevertheless, E-cadherin expression decreased significantly in prostate cancer specimens compared with benign prostatic hyperplasia (P < 0.05) and was negatively correlated with higher Gleason Score, distant metastases (P < 0.05). Correlation analysis revealed that LSD1 expression was negatively correlated with E-cadherin expression in prostate cancer (rs = -0.486, P = 0.001). Positive LSD1 expression and negative E-cadherin expression were significantly correlated with high 2-year progression (occurrence of castration-resistant prostate cancer) rate and low 5-year survival rate (P < 0.05). Moreover, Pargyline inhibited activity of LSD1 and up-regulated E-cadherin expression. High LSD1 expression combined with low E-cadherin expression might be predictors of prostate cancer progression and metastasis. Inhibition of LSD1 may be a potential therapeutic target for prevention of prostate cancer.

Stromal expression of miR-21 in T3-4a colorectal cancer is an independent predictor of early tumor relapse.

BackgroundMicroRNA-21 (miR-21) is an oncogenic microRNA that regulates the expression of multiple cancer-related target genes. miR-21 has been associated with progression of some types of cancer. Metastasis-associated protein1 expression and loss of E-cadherin expression are correlated with cancer progression and metastasis in many cancer types. In advanced colorectal cancer, the clinical significance of miR-21 expression remains unclear. We aimed to investigate the impact of miR-21 expression in advanced colorectal cancer and its correlation with target proteins associated with colorectal cancer progression.MethodsFrom 2004 to 2007, 277 consecutive patients with T3-4a colorectal cancer treated with R0 surgical resection were included. Patients with neoadjuvant therapy and distant metastasis at presentation were excluded. The expression of miR-21 was investigated by in situ hybridization. Immunohistochemistry was used to detect E-cadherin and metastasis-associated protein1 expression.ResultsHigh stromal expression of miR-21 was found in 76 of 277 (27.4%) colorectal cancer samples and was correlated with low E-cadherin expression (P = 0.019) and high metastasis-associated protein1 expression (P = 0.004). T3-4a colorectal cancer patients with high miR-21 expression had significantly shorter recurrence-free survival than those with low miR-21 expression. When analyzing colon and rectal cancer separately, high expression of miR-21 was an independent prognostic factor of unfavorable recurrence-free survival in T3-4a colon cancer patients (P = 0.038, HR = 2.45; 95% CI = 1.05-5.72) but not in T3-4a rectal cancer patients. In a sub-classification analysis, high miR-21 expression was associated with shorter recurrence-free survival in the stage II cancer (P = 0.001) but not in the stage III subgroup (P = 0.267).ConclusionsStromal miR-21 expression is related to the expression of E-cadherin and metastasis-associated protein1 in colorectal cancer. Stage II colorectal cancer patients with high levels of miR-21 are at higher risk for tumor recurrence and should be considered for more intensive treatment.

Preoperative Cervical Cytology and E-Cadherin Expression in Endometrial Cancer

Objective: It is reported that cervical cytology is a significant factor related to stage, tumor grade, nodal metastasis, recurrence and survival rate in endometrial cancer. Moreover, reduced expression of the cell adhesion molecule E-cadherin is associated with higher tumor grade and metastasis in endometrial cancer. The objective of this study is to evaluate the relationship between the results of cytological assessment of glandular cells in cervical cytology before surgery, prognostic factors, and E-cadherin expression in endometrial cancer. Methods: Between 2004 and 2011, 263 patients with endometrial cancer at all stages were treated with hysterectomy. We reviewed preoperative cervical smears and assigned each to one of three categories: (1) Negative, (2) Atypical glandular cells (AGC), and (3) Adenocarcinoma (AC). The relationship of these cytology, prognostic factors, and E-cadherin expression was evaluated. Results: Statistical significance in overall survival was shown for preoperative cervical cytology, age, surgical stage, histological type, tumor grade, myometrial invasion, cervical involvement, lymph node metastasis except peritoneal cytology. Patients with AC cytology were more likely than those with normal cervical cytology to have a higher International Federation of Gynecology and Obstetrics (FIGO) stage, poorer histopathology, higher tumor grade, deeper myometrial invasion, higher incidence of cervical involvement, and higher prevalence of lymph node metastasis. In addition, AC and AGC cytology appeared to be associated with a poorer prognosis and to have lower E-cadherin expression than negative cytology. Conclusions: Cervical cytology may be a guide to prognosis in endometrial cancer, and E-cadherin expression may correlate with appearances of abnormal endometrial cells.

Implications of the Notch1-Snail/Slug-epithelial to mesenchymal transition axis for lymph node metastasis in infiltrating ductal carcinoma

Emerging evidence suggests that activation of the Notch1 signaling pathway inducing epithelial to mesenchymal transition (EMT) mediated by Snail/Slug promotes invasion and metastasis of breast cancer cells in vitro. However, the implication of the Notch1-Snail/Slug-EMT axis in breast cancer patients remains unclear. A total of 200 formalin-fixed paraffin-embedded samples of invasive ductal carcinoma (IDC), and 37 adjacent non-neoplastic tissue (ANNT) samples from patients who had not been treated with neoadjuvant therapy were examined. Expression of Notch1, Slug, Snail, E-cadherin, N-cadherin, and vimentin was determined by immunohistochemistry on tissue microarrays (TMAs). The correlation between protein expression and clinicopathological characteristics of breast cancer patients was also evaluated. Results showed that a significantly high percentage of cases with high expression of Notch1 (74%, 148/200), Slug (36%, 72/200), Snail (62%, 124/200), and N-cadherin (77%, 153/200) and a low percentage of cases with high expression of E-cadherin (27%, 54/200) were observed in IDC compared to those in ANNTs. High Notch1, Slug, Snail, and N-cadherin expression and low E-cadherin expression in patients with IDC were significantly correlated with lymph node metastasis. In addition, correlation analysis results revealed that high Notch1 expression was significantly associated with high Slug, Snail, and N-cadherin expression and low E-cadherin expression in IDC. Furthermore, a high Snail expression was significantly associated with low E-cadherin expression, and a high Slug expression was found to be significantly associated with increased N-cadherin expression in patients with IDC. Hence, our study suggested that the Notch1-Snail/Slug-EMT axis may be implicated in the lymph node metastasis affecting patients with IDC.

Mesenchymal phenotype predisposes lung cancer cells to impaired proliferation and redox stress in response to glutaminase inhibition.

Recent work has highlighted glutaminase (GLS) as a key player in cancer cell metabolism, providing glutamine-derived carbon and nitrogen to pathways that support proliferation. There is significant interest in targeting GLS for cancer therapy, although the gene is not known to be mutated or amplified in tumors. As a result, identification of tractable markers that predict GLS dependence is needed for translation of GLS inhibitors to the clinic. Herein we validate a small molecule inhibitor of GLS and show that non-small cell lung cancer cells marked by low E-cadherin and high vimentin expression, hallmarks of a mesenchymal phenotype, are particularly sensitive to inhibition of the enzyme. Furthermore, lung cancer cells induced to undergo epithelial to mesenchymal transition (EMT) acquire sensitivity to the GLS inhibitor. Metabolic studies suggest that the mesenchymal cells have a reduced capacity for oxidative phosphorylation and increased susceptibility to oxidative stress, rendering them unable to cope with the perturbations induced by GLS inhibition. These findings elucidate selective metabolic dependencies of mesenchymal lung cancer cells and suggest novel pathways as potential targets in this aggressive cancer type.

Aberrant expression of osteopontin and E-cadherin indicates radiation resistance and poor prognosis for patients with cervical carcinoma.

Radiotherapy is the first-line treatment for all stages of cervical cancer, whether it is used for radical or palliative therapy. However, radioresistance of cervical cancer remains a major therapeutic problem. Consequently, we explored if E-cadherin (a marker of epithelial-mesenchymal transition) and osteopontin could predict radioresistance in patients with locally advanced cervical squamous cell carcinoma (LACSCC). Patients were retrospectively reviewed and 111 patients divided into two groups (radiation-resistant and radiation-sensitive groups) according to progression-free survival (PFS). In pretreated paraffin-embedded tissues, we evaluated E-cadherin and osteopontin expression using immunohistochemical staining. The percentage of patients with high osteopontin but low E-cadherin expression in the radiation-resistant group was significantly higher than those in the radiation-sensitive group (p<0.001). These patients also had a lower 5-year PFS rate (p<0.001). Our research suggests that high osteopontin but low E-cadherin expression can be considered as a negative, independent prognostic factor in patients with LACSCC ([Hazard ratios (95% CI) 6.766 (2.940, 15.572)], p<0.001).

BPTF Associated with EMT Indicates Negative Prognosis in Patients with Hepatocellular Carcinoma.

Epithelial-mesenchymal transition (EMT) plays an important role in hepatocellular carcinoma (HCC) dissemination. Bromodomain PHD-finger transcription factor (BPTF) could regulate embrogenesis and stem cell differentiation, and it may be involved in tumor progression and EMT. In this study, we aimed to determine BPTF, E-cadherin and vimentin expression in tumor tissues and the clinical significance in relation to HCC. The BPTF, vimentin and E-cadherin expression of 106 HCC tissue samples was examined by immunohistochemical staining. BPTF and vimentin showed high expression and E-cadherin showed low expression in HCC. BPTF is associated with the tumor number, vascular invasion, Edmondson-Steiner grade, TNM stage and recurrence (P < 0.05). Vimentin is positively correlated with tumor size, tumor number, vascular invasion, Edmondson-Steiner grade, TNM stage and recurrence (P < 0.05). E-cadherin is negatively correlated with tumor number, Edmondson-Steiner grade, TNM stage and recurrence (P < 0.05). Survival analysis has shown that high expression of BPTF and vimentin indicates poorer overall and disease-free survival (P < 0.05). Multivariate analysis shows that BPTF is an independent marker for survival prediction (P = 0.015). Additionally, high BPTF expression is correlated with high vimentin expression and low E-cadherin expression (P < 0.05). High BPTF expression may be an independent marker for survival prediction in HCC patients and is probably involved in EMT.

Immunohistochemical analysis of the expression of E-cadherin and ZEB1 in non-small cell lung cancer.

We performed an immunohistochemical analysis of the expression of zinc-finger E-box binding homeobox 1 (ZEB1), a master regulator of epithelial-mesenchymal transition (EMT), and determined its relationship with E-cadherin in 157 non-small cell lung carcinomas (93 adenocarcinomas, 36 squamous cell carcinomas, 18 large cell carcinomas, and 10 pleomorphic carcinomas). Although the expression of E-cadherin was low in the subset of adenocarcinomas (10%) and squamous cell carcinomas (11%), ZEB1 expression was only observed in one case of squamous cell carcinoma and none of the adenocarcinomas. In contrast, the low expression of E-cadherin (50% and 90%, respectively) and the positive expression of ZEB1 (11% and 50%, respectively) were more frequently observed in poorly differentiated carcinomas (large cell carcinomas and pleomorphic carcinomas). Overall, the expression of ZEB1 was inversely correlated with that of E-cadherin. Furthermore, the distribution of ZEB1-positive cancer cells was more restricted than in the area in which the expression of E-cadherin was lost, and the former was detected within the latter. We concluded that the expression of ZEB1 was not necessarily associated with the low expression of E-cadherin in lung adenocarcinomas and squamous cell carcinomas. The expression of ZEB1 correlated with an undifferentiated and/or sarcomatoid morphology that may occur in the late stage of EMT.

BDNF mediated TrkB activation contributes to the EMT progression and the poor prognosis in human salivary adenoid cystic carcinoma

The aim of the present study was to investigate whether the expression of Brain-Derived Neurotrophic Factor (BDNF) and its receptor Tropomyosin-related kinase B (TrkB) is correlated with the clinical progression of salivary adenoid cystic carcinoma (SACC) and whether the BDNF/TrkB axis is associated with the induction of epithelial-mesenchymal transition (EMT) in SACC cells. The expression of BDNF, TrkB, and E-cadherin (an EMT biomarker) in 76 primary SACC specimens and 20 normal salivary gland tissues was analyzed by immunohistochemistry. Additionally, the expression of BDNF, TrkB, and E-cadherin in SACC cell lines (SACC-83 and SACC-LM) was analyzed by RT-PCR and Western blotting. The biological role of the BDNF/TrkB axis in the EMT progression of SACC was evaluated after treatment with increased levels of BDNF and by inhibiting TrkB activity in SACC-83 cell line. The progression of SACC cells through EMT was assessed by RT-PCR, Western blotting, photography, migration and invasion assays. Elevated expression of TrkB (92.1%) and BDNF (89.5%), and downregulated expression of E-cadherin (47.4%) was found in SACC specimens, which was significantly correlated with the invasion and metastasis in SACC (P<0.05). The high expression of TrkB and the low expression of E-cadherin was significantly correlated with the poor prognosis of SACC patients (P<0.05). The expression of TrkB was inversely correlated with the expression of E-cadherin in both SACC cases and cell lines (P<0.05). Increasing BDNF levels after treatment with exogenous recombinant human BDNF (rhBDNF) at 100 ng/ml significantly promoted the activation of TrKB and the progression of EMT in SACC cells. While obstruction of TrkB by its inhibitor, k252a (100 nM), significantly inhibited the EMT progression of SACC cells. These results suggest that BDNF-mediated TrkB activation contributes to the EMT progression and the poor prognosis in SACC. The present study demonstrated that the BDNF/TrkB axis promotes the migration and invasion of SACC cells via EMT in vitro. Targeting the inactivation of the BDNF/TrkB axis may be a potential strategy for the treatment of SACC.

Epithelial-mesenchymal transition contributes to docetaxel resistance in human non-small cell lung cancer.

Lung cancer is an aggressive malignancy with high morbidity and mortality. Chemotherapy has always been the principal treatment measure, but its acquired resistance becomes a critical problem. In the current study, we established a new docetaxel-resistant human non-small lung cancer (NSCLC) cell line A549/Docetaxel. The resistance index (RI) of A549/Docetaxel cells and A549 induced by TGF-β to docetaxel were 8.91 and 11.5, respectively. Compared to the parental A549 cells, the multiplication time of A549/Docetaxel was prolonged, the proportion of the cell cycle in the S phase decreased while that in the G1 phase increased, and apoptotic rate was much lower. The morphology of the resistant cells eventuated epithelial–mesenchymal transition (EMT), which was confirmed by the higher expression of fibronectin, vimentin (mesenchymal markers), and lower expression of E-cadherin (epithelial marker) at mRNA and proteins levels. Furthermore, the representative markers for docetaxel resistance were examined, including ABCB1 (MDR1), Bcl-2, Bax, and tubulin, to figure out the mechanisms of the resistance of A549/Docetaxel. In summary, we have established a typical docetaxel-resistant human NSCLC cell line A549/Docetaxel, and it was suggested that the multidrug resistance of A549/Docetaxel was related to EMT.

E-cadherin and CD10 expression in atypical hyperplastic and malignant endometrial lesions

BackgroundLoss of E-cadherin is a critical step for development and progression of malignant tumors. CD10; a marker of non-neoplastic and neoplastic endometrial stroma, is associated with aggressiveness of many epithelial malignancies. AimsTo evaluate expression and correlation of E-cadherin and CD10 in endometrial lesions and their possible role in differentiating atypical endometrial hyperplasia from endometrial carcinoma. The association of E-cadherin and CD10 expression with clinico-pathological parameters of endometrial carcinoma was also investigated. Materials and methodsFifty four cases including 28 endometrial carcinomas; 19 endometrial hyperplasia and 7 cases of normal endometrial changes were enrolled for this study. The expression of E-cadherin and CD10 was evaluated by immunohistochemistry using the streptavidin–biotin technique. Results: There was a strong association between malignant change of endometrial glands and membrano-cytoplasmic localization of E-cadherin (p<0.001). Expression of E-cadherin but not CD10 was significantly higher in endometrial carcinomas compared to atypical endometrial hyperplasia (p<0.01). Expression of E-cadherin was not associated with CD10 expression in different endometrial lesions. High grade tumors expressed low levels of both E-cadherin (p<0.01) and CD10 (p<0.05) and serous endometrial carcinoma had low E-cadherin and CD10 expression compared to endometrioid carcinoma (p<0.01 and <0.05, respectively). Expression of both molecules showed no association with depth of tumor invasion or FIGO stage. Tumors with lower E-cadherin or CD10 expression had higher rates of vascular tumor emboli (p<0.01 and <0.07, respectively). ConclusionsAlthough expression of E-cadherin and CD10 in endometrial lesions was not correlated, reduced expression of both molecules could be critical for progression of endometrial carcinoma.

Abstract 1208: Androgen receptor expressing metaplastic carcinoma cell line established from non-caucasian female patient

Abstract Background: Metaplastic carcinoma (MCa) is a rare entity of breast cancer (BCa) where tumor of epithelial origin manifests differentiation into non-glandular, mesenchymal phenotype. These tumors exhibit heterogeneity with spindle, squamous, chondroid or osseous differentiation. Majority of these tumors do not express estrogen or progesterone receptors and are negative for HER-2/neu gene amplification, limiting use of available targeted therapies. This may translate into poor clinical outcome in this subset of patients as opposed to triple negative subtype of breast cancer. Cancer cell lines have been proved to be a valuable tool in understanding pathogenesis of BCa and development of appropriate drugs. Considering tumor heterogeneity, selecting an appropriate cell line model is imperative to understand signaling mechanisms of each of the distinct sub-types of BCa.Aim of this study was to establish and characterize a BCa cell line from a non-caucasian Pakistani patient. Methodology: Cell line was established from primary culture of tumor tissue from a 65 year old Pakistani female patient diagnosed with T4N1M0 MCa of breast. Specimen was procured in Dulbecco's Modified Eagle's Medium and processed under sterile conditions by mincing and gentle pipetting followed by culturing in complete medium supplemented with 10% fetal bovine serum. Epitheliod colonies were visualized after 3 weeks of culture, which were subsequently passaged and propagated. This cell line has been phenotypically and genotypically characterized using karyotyping, gene expression analysis, immunocytochemistry and florescent insitu hybridization (FISH). Results: Cell line has a human karyotype with multiploidy and population doubling time of 60 hours. Gene expression profiling revealed negative expression of ER, PR and positive expression of androgen receptor (AR) and HER-2/neu. FISH analysis was negative for HER-2/neu amplification. Both basal (cytokeratins 5, 14 &amp; 19) and luminal markers (cytokeratin 8 &amp; 18) are expressed at mRNA level along with myoepithelial markers (CD10, S100A7, p-cadherin, desmin, S100A4, S100A2 &amp; α-SMA). In accordance with mesenchymal phenotype, it has low expression of e-cadherin and high expression of vimentin. Invasion assay revealed this cell line to be non-invasive forming spheroids. CAG repeat length of AR is 22 and AR has been found to be functional by luciferase reporter assay in response to treatment with dihydrotestosterone. Conclusions: We report a novel metaplastic carcinoma cell line from a nan-caucasian female patient with functional AR. Targeting AR signaling may be a promising therapeutic target in this rare sub-type of BCa. Citation Format: Nazia Riaz, Zulfiqar Naqvi, Anwar Ali Siddiqui, Shaista Masood Khan, ElNasir Lalani. Androgen receptor expressing metaplastic carcinoma cell line established from non-caucasian female patient. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1208. doi:10.1158/1538-7445.AM2014-1208

Abstract 2349: An RNA-based epigenetic network controls the expression of E-cadherin in epithelial normal and cancer cells

Abstract Epigenetic mechanisms play important roles in many human diseases. However, what drives epigenetic regulators to specific genomic locations is still an open question. Promoter-associated long non-coding RNAs (paRNAs) have been identified in many genes and have been proposed to act as docking elements for recruitment of epigenetic regulators to gene promoters, although the underlying mechanisms are still poorly characterized. In this study we investigated the role of paRNAs in transcriptional regulation of E-cadherin (CDH1), a trans-membrane glycoprotein and an important determinant of epithelial cell differentiation. Transcriptional silencing of E-cadherin is frequent in epithelial cancers and loss of E-cadherin expression triggers epithelial-to-mesenchymal transition (EMT) and acquisition of tumor-initiating properties. We found that bidirectional transcription occurred from independent initiation sites in the E-cadherin promoter and generated sense (S) and antisense (AS) paRNAs that coordinated the transcriptional activity of the gene. S and AS paRNAs had distinct expression patterns in normal and cancer cell lines and human prostate tumors. Both in cancer cell lines and human tumors the prevalence of S paRNAs and low AS/S paRNA ratio were associated with low E-cadherin expression. We found that the S paRNA bound Argonaute 1 (AGO1) and coordinated silencing of the gene by recruiting, along with AGO1, the histone methyltransferase SUV39H1 to the promoter. Consistently, knockdown of either S paRNA or AGO1 reduced SUV39H1 promoter occupancy and reactivated E-cadherin transcription in low expressing cells. Using promoter reporter and expression constructs we showed that the S paRNA and AGO1 acted in cis to control promoter activity and that the interaction with AGO1 required specific element of the S paRNA. Furthermore, recruitment of AGO1 to the S paRNA and CDH1 promoter depended on an isomiR derived through alternative processing and editing of pre-miR-4534. Accordingly, mutations that disrupted the isomiR binding sequence in the S paRNA reduced AGO1 binding and increased promoter activity, while depletion of the isomiR induced CDH1 expression. Notably, the novel isomiR was more abundant in transformed epithelial cells and cancer cell lines than normal prostate epithelial cells, accumulated preferentially in nuclei and was specifically associated with S paRNA and chromatin-bound AGO1 in low CDH1 expressing cancer cells. This study reveals a complex RNA-based epigenetic network that relies on sequence-specific interactions between a paRNA, a small RNA and AGO1 and coordinates transcriptional silencing of a critical gene involved in tumor development and progression. Our findings give also a new prospective and mechanistic insights on the interplay between epigenetic regulatory factors indentifying paRNAs as relevant elements in these processes and potential targets for gene modulation strategies. Citation Format: Sara Napoli, Giuseppina Pisignano, Ramon Garcia-Escudero, Giuseppina Carbone, Carlo V. Catapano. An RNA-based epigenetic network controls the expression of E-cadherin in epithelial normal and cancer cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2349. doi:10.1158/1538-7445.AM2014-2349

Dysregulated expression of Snail and E-cadherin correlates with gastrointestinal stromal tumor metastasis.

Snail, a zinc finger structure transcription inhibitory factor, has been reported to play an important role in the metastatic progression of several types of cancer. The aim of the study was to identify potential biomarkers for metastasis in gastrointestinal stromal tumors (GISTs) by examining the expression levels of Snail, E-cadherin, and Vimentin in GISTs and investigate their clinical significance. The protein expression of Snail, E-cadherin, and Vimentin in 74 GIST specimens was detected by immunohistochemical analysis, and the correlation between expression levels and clinicopathological data was analyzed. Snail, E-cadherin, and Vimentin were positively expressed in 51.4% (38/74), 32.4% (24/74), and 68.9% (51/74) of GIST tissue samples, respectively. Snail protein expression was significantly higher in GISTs with distant metastasis compared with GISTs without distant metastasis (P<0.05). E-cadherin expression level was significantly lower in cases of GIST with distant metastasis compared with those without distant metastasis (P<0.05), whereas the expression level of Vimentin did not significantly change according to clinical and pathological characteristics (all P>0.05). Snail expression was significantly negatively correlated with E-cadherin expression (r's=-0.276, P=0.017) but not with Vimentin expression (r's=0.041, P=0.728) in GISTs. High Snail expression and low E-cadherin expression were significantly correlated with metastasis in GISTs, and Snail, because of positive correlation, is potentially a biomarker of GIST with distant metastasis.

SDF-1/CXCR4 promotes epithelial–mesenchymal transition and progression of colorectal cancer by activation of the Wnt/β-catenin signaling pathway

Stromal cell-derived factor 1 (SDF-1) and its receptor, CXCR4, play an important role in angiogenesis and are associated with tumor progression. This study aimed to investigate the role of SDF-1/CXCR4-mediated epithelial–mesenchymal transition (EMT) and the progression of colorectal cancer (CRC) as well as the underlying mechanisms. The data showed that expression of CXCR4 and β-catenin mRNA and protein was significantly higher in CRC tissues than in distant normal tissues. CXCR4 expression was associated with β-catenin expression in CRC tissues, whereas high CXCR4 expression was strongly associated with low E-cadherin, high N-cadherin, and high vimentin expression, suggesting a cross talk between the SDF-1/CXCR4 axis and Wnt/β-catenin signaling pathway in CRC. In vitro, SDF-1 induced CXCR4-positive colorectal cancer cell invasion and EMT by activation of the Wnt/β-catenin signaling pathway. In contrast, SDF-1/CXCR4 axis activation-induced colorectal cancer invasion and EMT was effectively inhibited by the Wnt signaling pathway inhibitor Dickkopf-1. In conclusion, CXCR4-promoted CRC progression and EMT were regulated by the Wnt/β-catenin signaling pathway. Thus, targeting of the SDF-1/CXCR4 axis could have clinical applications in suppressing CRC progression.

Sonic hedgehog signaling may promote invasion and metastasis of oral squamous cell carcinoma by activating MMP-9 and E-cadherin expression.

The aim of this study was to investigate sonic hedgehog (SHH) signaling pathway components (Shh and Gli-1), E-cadherin, and MMP-9 expression in human oral squamous cell carcinoma (OSCC) and to evaluate their role in prognosis. Expression of Shh, Gli-1, and MMP-9 was significantly upregulated in 74 OSCC samples compared with non-cancerous tissue samples (Shh IOD: 162.44 ± 29.35 and 608.82 ± 170.99; Gli-1 IOD: 203.50 ± 71.57 and 831.11 ± 242.352; MMP-9 IOD: 196.69 ± 64.48 and 721.64 ± 197.99 in non-cancerous and tumor tissues, respectively, P < 0.01), whereas E-cadherin expression was downregulated (E-cadherin IOD: 1,006.19 ± 230.42 and 442.20 ± 156.11; in non-cancerous and tumor tissues, respectively, P < 0.01). Highly expressed proteins were associated with lymph node metastasis; moreover, overexpression of Gli-1 was related to tumor recurrence and cancer clinical staging. Spearman's analysis indicated that the expression of Gli-1 and MMP-9 was positively correlated, whereas expression of Shh/Gli-1 and E-cadherin was negatively correlated. Kaplan-Meier results revealed that patients with low Shh, Gli-1, and MMP-9 expression survived longer than those with high expression. In contrast, low E-cadherin expression was associated with poor prognosis (P < 0.01). In conclusions, transcription factor Gli-1 of the SHH signaling pathway may be an important mediator of invasion and metastasis of OSCC through induced expression of MMP-9 and E-cadherin and may serve as a new prognostic marker.

The Role of E-Cadherin Down-Regulation in Oral Cancer: CDH1 Gene Expression and Epigenetic Blockage

The prognosis of the oral squamous cell carcinoma (OSCC) patients remains very poor, mainly due to their high propensity to invade and metastasize. E-cadherin reduced expression occurs in the primary step of oral tumour progression and gene methylation is a mode by which the expression of this protein is regulated in cancers. In this perspective, we investigated E-cadherin gene (CDH1) promoter methylation status in OSCC and its correlation with Ecadherin protein expression, clinicopathological characteristics and patient outcome. Histologically proven OSCC and paired normal mucosa were analyzed for CDH1 promoter methylation status and E-cadherin protein expression by methylation-specific polymerase chain reaction and immunohistochemistry. Colocalization of E-cadherin with epidermal growth factor (EGF) receptor (EGFR) was evidenced by confocal microscopy and by immunoprecipitation analyses. This study indicated E-cadherin protein down-regulation in OSCC associated with protein delocalization from membrane to cytoplasm. Low E-cadherin expression correlated to aggressive, poorly differentiated, high grade carcinomas and low patient survival. Moreover, protein down-regulation appeared to be due to E-cadherin mRNA downregulation and CDH1 promoter hypermethylation. In an in vitro model of OSCC the treatment with EGF caused internalization and co-localization of E-cadherin with EGFR and the addition of demethylating agents increased E-cadherin expression. Low E-Cadherin expression is a negative prognostic factor of OSCC and is likely due to the hypermethylation of CDH1 promoter. The delocalization of E-cadherin from membrane to cytoplasm could be also due to the increased expression of EGFR in OSCC and the consequent increase of E-cadherin co-internalization with EGFR.

The Integrin β1 Subunit Regulates Paracellular Permeability of Kidney Proximal Tubule Cells

Epithelial cells lining the gastrointestinal tract and kidney have different abilities to facilitate paracellular and transcellular transport of water and solutes. In the kidney, the proximal tubule allows both transcellular and paracellular transport, while the collecting duct primarily facilitates transcellular transport. The claudins and E-cadherin are major structural and functional components regulating paracellular transport. In this study we present the novel finding that the transmembrane matrix receptors, integrins, play a role in regulating paracellular transport of renal proximal tubule cells. Deleting the integrin β1 subunit in these cells converts them from a "loose" epithelium, characterized by low expression of E-cadherin and claudin-7 and high expression of claudin-2, to a "tight" epithelium with increased E-cadherin and claudin-7 expression and decreased claudin-2 expression. This effect is mediated by the integrin β1 cytoplasmic tail and does not entail β1 heterodimerization with an α-subunit or its localization to the cell surface. In addition, we demonstrate that deleting the β1 subunit in the proximal tubule of the kidney results in a major urine-concentrating defect. Thus, the integrin β1 tail plays a key role in regulating the composition and function of tight and adherens junctions that define paracellular transport properties of terminally differentiated renal proximal tubule epithelial cells.

Desmoplastic Melanoma

Desmoplastic melanoma (DM) is a rare variant of melanoma. Most frequently, it seems as clinically ambiguous and histologically characterized by a poorly demarcated neoplasm composed of a proliferation of spindle melanocytes dispersed in a prominent collagenous stroma. It often represents a diagnostic challenge, delaying its detection. We analyzed the expression profile of 29 (28 "pure" and 1 "combined") DM. These data were compared with a series of 62 primary vertical growth phase nondesmoplastic melanomas (NDMs) using a set of proteins including melanocytic markers (S-100 protein and melan-A) and epithelial-mesenchymal transition (EMT)-related proteins (E-cadherin, N-cadherin, SPARC, WT1, and PKCα). The S-100 protein confirmed the melanocytic origin of the DM (positive in 96%). The significant positive expression of N-cadherin, SPARC, and WT1 in DM (61%, 82%, and 71%) compared with NDM (28%, 43%, and 47%; P < 0.05) and a lower expression of E-cadherin in DM (14%) compared with NDM (61%) support specific adhesive and migratory properties of DM tumor cells. The study was carried out with tissue microarrays that partly limited the study of the tumor sections. This study demonstrates, for the first time, a prominent expression of epithelial-mesenchymal transition-related proteins in DMs and tries to be one more step in refining its knowledge and leading to a better understanding of its biological and clinical behaviors.

E-cadherin expression and prognosis of oral cancer: a meta-analysis

This study aims to evaluate the association of E-cadherin expression with the prognosis of oral squamous cell carcinoma (OSCC). Literature retrieval, selection and assessment, data extraction, and meta-analyses were performed according to the Revman 5.0 guidelines. In the meta-analysis, we utilized either fixed effects or random effects model to pool the HR according to the test of heterogeneity. A total of nine eligible studies included 973 OSCC patients were analyzed. Of the patients, 76.3 % had low expression of E-cadherin according to the cutoff value defined by the authors. The pooled hazard ratio (HR) of low expression of E-cadherin for overall survival (OS) was 0.65 (95 % CI 0.52 to 0.80, P<0.001); in Asian population, the HR for overall survival of the patients with reduced expression of E-cadherin was 0.84 (95 % CI 0.75 to 0.95, P=0.006), and in non-Asian population, the HR for overall survival of the patients with reduced expression of E-cadherin was 0.54 (95 % CI 0.41 to 0.69, P<0.001). Patients with reduced expression of E-cadherin appear to have a poorer OS compared with those with normal or higher expression of E-cadherin.