Expression of e-cadherin in high-risk breast cancer

Hypoxia-Induced LIN28A mRNA Promotes the Metastasis of Colon Cancer in a Protein-Coding-Independent Manner

The hypoxic microenvironment is beneficial to the metastasis but not to the proliferation of cancer cells. However, the mechanisms regarding to hypoxia differentially regulating cancer metastasis and proliferation are largely unknown. In this study, we revealed that hypoxia induced the expression of LIN28A at mRNA level but segregated LIN28A mRNAs in the P-bodies and thus inhibits the production of LIN28A protein. This unexpected finding suggests that there may be non-coding role for LIN28A mRNA in the progression of colon cancer. We further showed that the non-coding LIN28A mRNA promotes the metastasis but not proliferation of colon cancer cells in vitro and in vivo. Mechanistically, we revealed that methionyl aminopeptidase 2 (METAP2) is one of the up-regulated metastasis regulators upon over-expression of non-coding LIN28A identified by mass spectrum, and confirmed that it is non-coding LIN28A mRNA instead of LIN28A protein promotes the expression of METAP2. Moreover, we demonstrated that knockdown of DICER abolished the promotional effects of non-coding LIN28A on the metastasis and METAP2 expression. Conclusively, we showed that hypoxia induces the production of LIN28A mRNAs but segregated them into the P-bodies together with miRNAs targeting both LIN28A and METAP2, and then promotes the metastasis by positively regulating the expression of METAP2. This study uncovered a distinctive role of hypoxia in manipulating the metastasis and proliferation by differently regulating the expression of LIN28A at mRNA and protein level.

A subset of activated fibroblasts is associated with distant relapse in early luminal breast cancer

Background

Early luminal breast cancer (BC) represents 70% of newly diagnosed BC cases. Among them, small (under 2 cm) BC without lymph node metastasis (classified as T1N0) have been rarely studied, as their prognosis is generally favorable. Nevertheless, up to 5% of luminal T1N0 BC patients relapse with distant metastases that ultimately prove fatal. The aim of our work was to identify the mechanisms involved in metastatic recurrence in these patients.

Methods

Our study addresses the role that autonomous and non-autonomous tumor cell features play with regard to distant recurrence in early luminal BC patients. We created a cohort of T1N0 luminal BC patients (tumors between 0.5–2 cm without lymph node metastasis) with metastatic recurrence (“cases”) and corresponding “controls” (without relapse) matched 1:1 on main prognostic factors: age, grade, and proliferation. We deciphered different characteristics of cancer cells and their tumor micro-environment (TME) by deep analyses using immunohistochemistry. We performed in vitro functional assays and highlighted a new mechanism of cooperation between cancer cells and one particular subset of cancer-associated fibroblasts (CAF).

Results

We found that specific TME features are indicative of relapse in early luminal BC. Indeed, quantitative histological analyses reveal that “cases” are characterized by significant accumulation of a particular CAF subset (CAF-S1) and decrease in CD4⁺ T lymphocytes, without any other association with immune cells. In multivariate analysis, TME features, in particular CAF-S1 enrichment, remain significantly associated with recurrence, thereby demonstrating their clinical relevance. Finally, by performing functional analyses, we demonstrated that CAF-S1 pro-metastatic activity is mediated by the CDH11/osteoblast cadherin, consistent with bones being a major site of metastases in luminal BC patients.

Conclusions

This study shows that distant recurrence in T1N0 BC is strongly associated with the presence of CAF-S1 fibroblasts. Moreover, we identify CDH11 as a key player in CAF-S1-mediated pro-metastatic activity. This is independent of tumor cells and represents a new prognostic factor. These results could assist clinicians in identifying luminal BC patients with high risk of relapse. Targeted therapies against CAF-S1 using anti-FAP antibody or CDH11-targeting compounds might help in preventing relapse for such patients with activated stroma.

Nuclear accumulation of CDH1 mRNA in hepatocellular carcinoma cells

Expression of E-cadherin has a central role in maintaining epithelial morphology. In solid tumors, reduction of E-cadherin results in disruption of intercellular contacts. Consequently, cells lose adhesive properties and gain more invasive mesenchymal properties. Nevertheless, the mechanism of E-cadherin regulation is not completely elucidated. Here we analyzed the distribution of E-cadherin expression at the cell level in human hepatocellular carcinoma, in which human liver paraffin blocks from 25 hepatocellular carcinoma patients were prepared from cancerous (CA) and noncancerous areas (NCA). In situ hybridization (ISH) was performed to detect E-cadherin and hypoxia-induced factor-1α (HIF1α) mRNAs and immunohistochemistry to stain E-cadherin protein. In parallel, RNA was extracted from CA and NCA, and E-cadherin and HIF1α were quantified by quantitative reverse transcription PCR. ISH revealed abundant E-cadherin mRNA in nuclei of hepatocellular carcinoma cells (HCCs), whereas immunohistochemistry showed depletion of E-cadherin protein from these areas. In sections of NCA, E-cadherin mRNA was also found in the cytosol, and E-cadherin protein was detected on the membrane of cells. Experiments in cell lines confirmed E-cadherin mRNA in nuclei of cells negative for E-cadherin protein. HIF1α expression is elevated in CAs, which is associated with a clear cytosolic staining for this mRNA. Our results demonstrate that E-caderhin mRNA is selectively retained in nuclei of HCCs, whereas other mRNAs are still exported, suggesting that translocation of E-cadherin mRNA from nuclei to cytoplasm has a role in regulating E-cadherin protein levels during epithelial mesenchymal transition.

Aberrant P-cadherin expression is associated to aggressive feline mammary carcinomas

BACKGROUND

Cadherins are calcium-dependent cell-to-cell adhesion glycoproteins playing a critical role in the formation and maintenance of normal tissue architecture. In normal mammary gland, E-cadherin is expressed by luminal epithelial cells, while P-cadherin is restricted to myoepithelial cells. Changes in the expression of classical E- and P-cadherins have been observed in mammary lesions and related to mammary carcinogenesis. P-cadherin and E-cadherin expressions were studied in a series of feline normal mammary glands, hyperplastic/dysplastic lesions, benign and malignant tumours by immunohistochemistry and double-label immunofluorescence.

RESULTS

In normal tissue and in the majority of hyperplastic/dysplastic lesions and benign tumours, P-cadherin was restricted to myoepithelial cells, while 80% of the malignant tumours expressed P-cadherin in luminal epithelial cells. P-cadherin expression was significantly related to high histological grade of carcinomas (p <0.0001), tumour necrosis (p = 0.001), infiltrative growth (p = 0.0051), and presence of neoplastic emboli (p = 0.0401). Moreover, P-cadherin positive carcinomas had an eightfold likelihood of developing neoplastic emboli than negative tumours. Cadherins expression profile in high grade and in infiltrative tumours was similar, the majority expressing P-cadherin, regardless of E-cadherin expression status. The two cadherins were found to be co-expressed in carcinomas with aberrant P-cadherin expression and preserved E-cadherin.

CONCLUSIONS

The results demonstrate a relationship between P-cadherin expression and aggressive biological behaviour of feline mammary carcinomas, suggesting that P-cadherin may be considered an indicator of poor prognosis in this animal species. Moreover, it indicates that, in queens, the aberrant expression of P-cadherin is a better marker of mammary carcinomas aggressive behaviour than the reduction of E-cadherin expression. Further investigation with follow-up studies in feline species should be conducted in order to evaluate the prognostic value of P-cadherin expression in E-cadherin positive carcinomas.

Γ-secretase components as predictors of breast cancer outcome

γ-secretase is a large ubiquitously expressed protease complex composed of four core subunits: presenilin, Aph1, PEN-2, and nicastrin. The function of γ-secretase in the cells is to proteolytically cleave various proteins within their transmembrane domains. Presenilin and Aph1 occur as alternative variants belonging to mutually exclusive γ-secretase complexes and providing the complexes with heterogeneous biochemical and physiological properties. γ-secretase is proposed to have a role in the development and progression of cancer and γ-secretase inhibitors are intensively studied for their probable anti-tumor effects in various types of cancer models. Here, we for the first time determined mRNA expression levels of presenilin-1, presenilin-2, Aph1a, Aph1b, PEN-2, and nicastrin in a set of breast cancer tissue samples (N = 55) by quantitative real-time PCR in order to clarify the clinical significance of the expression of different γ-secretase complex components in breast cancer. We found a high positive correlation between the subunit expression levels implying a common regulation of transcription. Our univariate Kaplan-Meier survival analyses established low expression level of γ-secretase complex as a risk factor for breast cancer specific mortality. The tumors expressing low levels of γ-secretase complex were characterized by high histopathological tumor grade, low or no expression of estrogen and progesterone receptors and consequently high probability to fall into the class of triple negative breast cancer tumors. These results may provide novel tools to further categorize breast cancer tumors, especially the highly aggressive and poorly treatable breast cancer type of triple negative cases, and suggest a significant role for γ-secretase in breast cancer.

Cadherin cell adhesion system in canine mammary cancer: a review

Cadherin-catenin adhesion complexes play important roles by providing cell-cell adhesion and communication in different organ systems. Abnormal expression of cadherin adhesion molecules constitutes a common phenomenon in canine mammary cancer and has been frequently implicated in tumour progression. This paper summarizes the current knowledge on cadherin/catenin adhesion molecules (E-cadherin, β-catenin, and P-cadherin) in canine mammary cancer, focusing on the putative biological functions and clinical significance of these molecules in this disease. This paper highlights the need for further research studies in this setting in order to elucidate the role of these adhesion molecules during tumour progression and metastasis.

An immunohistochemically positive E-cadherin status is not always predictive for a good prognosis in human breast cancer

Background:

In primary breast cancers dichotomic classification of E-cadherin expression, according to an arbitrary cutoff, may be inadequate and lead to loss of prognostic significance or contrasting prognostic indications. We aimed to assess the prognostic value of high and low E-cadherin levels in a consecutive case series (204 cases) of unilateral node-negative non-lobular breast cancer patients with a 8-year median follow-up and that did not receive any adjuvant therapy after surgery.

Methods:

Expression of E-cadherin was investigated by immunohistochemistry and assessed according to conventional score (0, 1+, 2+, 3+). Multiple correspondence analysis was used to visualise associations of both categorical and continuous variables. The impact of E-cadherin expression on patients outcome was evaluated in terms of event-free survival curves by the Kaplan–Meier method and proportional hazard Cox model.

Results:

Respect to intermediate E-cadherin expression values (2+), high (3+) or low (0 to 1+) E-cadherin expression levels had a negative prognostic impact. In fact, both patients with a low-to-nil (score 0 to 1+) expression level of E-cadherin and patients with a high E-cadherin expression level (score 3+) demonstrated an increased risk of failure (respectively, hazard ratio (HR)=1.71, confidence interval (CI)=0.72–4.06 and HR=4.22, CI=1.406–12.66) and an interesting association with young age.

Conclusions:

The findings support the evidence that high expression values of E-cadherin are not predictive for a good prognosis and may help to explain conflicting evidence on the prognostic impact of E-cadherin in breast cancer when assessed on dichotomic basis.

Real time PCR analyses of expression of E-cadherin, alpha-, beta- and gamma-catenin in human breast cancer for predicting clinical outcome

Background

The E-cadherin catenin system acts as an invasion suppressor of epithelial malignancies. However, it is debatable whether expression of E-cadherin or catenins is a useful prognostic marker in invasive breast cancer.

Methods

We measured the expression of E-cadherin and catenins (α-, β-, γ-catenin) in human breast carcinomas using real time quantitative polymerase chain reaction (Q-PCR) and investigated whether the expression levels were associated with known tumour variables or patient survival (median follow-up 72.2 months). RNA from frozen sections of breast tissue (tumour n = 124, background normal tissue n = 33) was reverse transcribed, quantified and analysed by Q-PCR with results expressed as number of copies of transcript/50 ng RNA.

Results

There was no statistically significant difference in the expression of E-cadherin and catenins (α-, β-, γ-catenin)in the 33 paired normal background and tumour tissues. The expression of E-cadherin, α-, β-, and γ-catenin in node positive tumours was similar to node-negative tumours. E-cadherin, α-, β-, and γ-catenin expression in breast tumours was not related to Nottingham Prognostic Index (NPI). There was no significant difference in the expression of E-cadherin, α-, β-, γ-catenin between the various TNM stages. None of the molecular markers significantly influenced survival. Lymph node status was the only significant predictor of survival.

Conclusion

Using real time quantitative PCR there was no difference in the expression of E-cadherin, α-, β-, γ-catenin between tumour and normal breast tissue. Furthermore, measurement of expression of these molecules was not of prognostic value in predicting long term outcome of women with breast cancer.

P-cadherin and beta-catenin are useful prognostic markers in breast cancer patients; beta-catenin interacts with heat shock protein Hsp27

The cadherin-catenin proteins have in common with heat shock proteins (HSP) the capacity to bind/interact proteins of other classes. Moreover, there are common molecular pathways that connect the HSP response and the cadherin-catenin protein system. In the present study, we have explored whether in breast cancer the HSP might interact functionally with the cadherin-catenin cell adhesion system. Beta-catenin was immunoprecipitated from breast cancer biopsy samples, and the protein complexes isolated in this way were probed with antibodies against HSP family members. We are thus the first to demonstrate a specific interaction between beta-catenin and Hsp27. However, beta-catenin did not bind Hsp60, Hsp70, Hsp90, gp96, or the endoplasmic reticulum stress response protein CHOP. To confirm the finding of Hsp27-beta-catenin interaction, the 27-kDa immunoprecipitated band was excised from one-dimensional polyacrylamide gel electrophoresis gels and submitted to liquid chromatography-tandem mass spectrometry with electrospray ionization, confirming a role for Hsp27. In addition, beta-catenin interacted with other proteins including heat shock transcription factor 1, P-cadherin, and caveolin-1. In human breast cancer biopsy samples, beta-catenin was coexpressed in the same tumor areas and in the same tumor cells that expressed Hsp27. However, this coexpression was strong when beta-catenin was present in the cytoplasm of the tumor cells and not when beta-catenin was expressed at the cell surface only. Furthermore, murine breast cancer cells transfected with hsp25 showed a redistribution of beta-catenin from the cell membrane to the cytoplasm. When the prognostic significance of cadherin-catenin expression was examined by immunohistochemistry in breast cancer patients (n = 215, follow-up = >10 years), we found that the disease-free survival and overall survival were significantly shorter for patients expressing P-cadherin and for patients showing expression of beta-catenin in the cytoplasm only (not at the cell surface). The interactions of beta-catenin with Hsp27 and with HSF1 may explain some of the molecular pathways that influence tumor cell survival and the clinical significance in the prognosis of the breast cancer patients.

Inflammatory breast cancers in Tunisia and France show similar immunophenotypes

PURPOSE

Inflammatory breast cancers (IBC) have specific immunophenotypic profiles as compared to non-inflammatory (non-IBC): combined differential expression of estrogen receptor, Ki67, E-cadherin, MUC1, and ERBB2 can be used as an IBC signature. It is thought that IBC occurs with a high frequency in Tunisia. The aim of this study is to evaluate this signature on a Tunisian series.

METHODS

The expression of five proteins (E-cadherin, ERBB2, estrogen receptor, Ki67, MUC1) was studied by immunohistochemistry on a consecutive series of 91 cases of IBC (T4D) treated at Tunisian Salah Azaiz Institute (ISA) and deposited in a tissue microarray (TMA). Results were compared to the same study on a series of 85 cases treated in France.

RESULTS

The ISA cases were characterized by a significantly younger age of patients (median: 42 years old in ISA for 53.5 in IPC, p=0.00042) and a higher frequency of invasive micropapillary pattern. None of the five parameters was expressed differentially in the two series. In non-metastatic patients, high level of proliferation (Ki67) and overexpression of ERBB2 were associated with poor outcome.

CONCLUSION

The IBC from Tunisia were not different from those observed in France on the basis of IHC profiles. However, the younger age of the patients suggest a specific epidemiological context that should be investigated.

Expression of E-cadherin, P-cadherin and beta-catenin in canine malignant mammary tumours in relation to clinicopathological parameters, proliferation and survival

Cadherin-catenin complexes play a critical role in intercellular adhesion, and their altered expression has been implicated in tumour progression. In this study, the expression of E-cadherin, P-cadherin and beta-catenin was analysed in 65 canine malignant mammary tumours and correlated with clinicopathological parameters, proliferation and survival. Reduction in E-cadherin expression was significantly associated with increased tumour size, high histological and invasion grades, lymph node metastasis and high mitotic index. Reduced beta-catenin expression was associated with high histological and invasion grades. Anomalous expression of P-cadherin was only associated with invasion. In 39 cases for which follow-up data were available, reduced E-cadherin and beta-catenin expression was significantly associated with shorter overall survival and disease free survival. Abnormal expression of adhesion molecules is a common phenomenon in canine mammary malignant tumours and may play a central role in tumour progression.

Expression pattern of adhesion molecules (E-cadherin, alpha-, beta-, gamma-catenin and claudin-7), their influence on survival in primary breast carcinoma, and their corresponding axillary lymph node metastasis

Reduced intercellular adhesion is implicated in the development of metastasis. This study investigates the expression of intercellular adhesion molecules (E-cadherin, alpha-, beta-, gamma-catenin and claudin-7) and their influence on survival in primary breast carcinomas and corresponding axillary lymph node metastases (ALNM), and evaluates associations between them and with clinicopathological factors. The expression of adhesion molecules was analyzed immunohistochemically in tissues from 196 patients with primary invasive breast carcinomas and their nodal metastases (174 ductal and 22 lobular types). The expression was evaluated using semi-quantitative scoring of the intensity and proportion of immunoreactivity. All five adhesion proteins showed significantly reduced expression in primary ductal carcinomas with re-expression in ALNM (p<0.001). In uni- and multivariate analyses, the expression of E-cadherin in the primary tumours was a significant predictor of disease-free survival and distant disease-free survival. Thus, abnormal E-cadherin expression in the primary invasive breast carcinoma seems to be an independent prognostic biomarker in predicting a shorter survival in node-positive breast cancer patients. The results indicate that abnormal expression of the adhesion molecules in the primary tumours with re-expression in corresponding nodal metastases is a common event in breast ductal carcinomas and may play a central role in establishing metastasis.

E-cadherin Immunohistochemical Expression as a Prognostic Factor in Infiltrating Ductal Carcinoma of the Breast: a Systematic Review and Meta-Analysis

PURPOSE

Multiple studies examining the relationship between loss of E-cadherin expression, a pivotal event for evolving metastatic behavior among epithelially derived cancers, and 5-year survival in infiltrating ductal breast carcinoma have yielded inconclusive and contradictory results.

EXPERIMENTAL DESIGN

We conducted a systematic review of the PubMed database through August 2005 with no language restrictions to identify cohort studies that evaluated E-cadherin immunohistochemical expression as a prognostic marker for ductal breast carcinoma. 5-year all-cause mortality or 5-year breast cancer-specific mortality were the primary study outcomes. Meta-analysis was conducted using the REVMAN software and summary hazard ratios assuming both fixed effect and random effect models were calculated.

RESULTS

Ten retrospective cohort studies were identified. Reduced or absent E-cadherin expression significantly increased the risk of all-cause mortality [combined HR = 1.55; 95% CI = 1.08-2.23] whereas a non-significant association was observed for breast cancer-specific mortality [combined HR = 0.70; 95% CI = 0.39-1.27]. We documented substantial inter-study heterogeneity with respect to all aspects of clinical data collection, immunohistochemical staining and interpretation as well as statistical modeling. These factors could not be formally analyzed but they challenge the robustness of our calculated summary estimates.

CONCLUSIONS

Loss of E-cadherin expression may be an independent negative prognostic indicator for infiltrating ductal breast carcinoma and randomized, controlled studies evaluating this finding are justified. We encourage standardization of immunohistochemical techniques, data interpretation algorithms across laboratories and use of all-cause mortality to increase data compatibility and facilitate future efforts summarizing the utility of alternate prognostic markers in cancer.

E-cadherin expression in canine malignant mammary tumours: relationship to other clinico-pathological variables

The relationship between E-cadherin epithelial expression, as detected by immunohistochemical methods, and other clinico-pathological characteristics of canine malignant mammary tumours was studied in 77 tumours surgically removed from 45 female dogs. The immunohistochemical assessment was based on the estimated percentage of epithelial cells with membranous labelling. Reduction of E-cadherin expression was significantly related to size and ulceration of tumours but not to fixation to skin or underlying tissue; it was also related to lymph node metastasis, necrosis and infiltrative growth. Histological type (but not histological grade) was related to E-cadherin expression, with solid tumours more frequently lacking expression and tubulopapillary tumours showing increased expression as compared with the other types. The significant relationship between E-cadherin and other known factors of poor prognosis suggests that the loss of E-cadherin expression may have prognostic value in canine malignant mammary tumours.

CDH1 promoter hypermethylation and E-cadherin protein expression in infiltrating breast cancer

Background

The E-cadherin gene (CDH1) maps, at chromosome 16q22.1, a region often associated with loss of heterozygosity (LOH) in human breast cancer. LOH at this site is thought to lead to loss of function of this tumor suppressor gene and was correlated with decreased disease-free survival, poor prognosis, and metastasis. Differential CpG island methylation in the promoter region of the CDH1 gene might be an alternative way for the loss of expression and function of E-cadherin, leading to loss of tissue integrity, an essential step in tumor progression.

Methods

The aim of our study was to assess, by Methylation-Specific Polymerase Chain Reaction (MSP), the methylation pattern of the CDH1 gene and its possible correlation with the expression of E-cadherin and other standard immunohistochemical parameters (Her-2, ER, PgR, p53, and K-67) in a series of 79 primary breast cancers (71 infiltrating ductal, 5 infiltrating lobular, 1 metaplastic, 1 apocrine, and 1 papillary carcinoma).

Results

CDH1 hypermethylation was observed in 72% of the cases including 52/71 ductal, 4/5 lobular carcinomas and 1 apocrine carcinoma. Reduced levels of E-cadherin protein were observed in 85% of our samples. Although not statistically significant, the levels of E-cadherin expression tended to diminish with the CDH1 promoter region methylation. In the group of 71 ductal cancinomas, most of the cases of showing CDH1 hypermethylation also presented reduced levels of expression of ER and PgR proteins, and a possible association was observed between CDH1 methylation and ER expression (p = 0.0301, Fisher's exact test). However, this finding was not considered significant after Bonferroni correction of p-value.

Conclusion

Our preliminary findings suggested that abnormal CDH1 methylation occurs in high frequencies in infiltrating breast cancers associated with a decrease in E-cadherin expression in a subgroup of cases characterized by loss of expression of other important genes to the mammary carcinogenesis process, probably due to the disruption of the mechanism of maintenance of DNA methylation in tumoral cells.