Cytoplasmic redistribution of E-cadherin-catenin adhesion complex is associated with down-regulated tyrosine phosphorylation of E-cadherin in human bronchopulmonary carcinomas

BZD9L1 sirtuin inhibitor: Identification of key molecular targets and their biological functions in HCT 116 colorectal cancer cells

BZD9L1 was previously described as a SIRT1/2 inhibitor with anti-cancer activities in colorectal cancer (CRC), either as a standalone chemotherapy or in combination with 5-fluorouracil. BZD9L1 was reported to induce apoptosis in CRC cells; however, the network of intracellular pathways and crosstalk between molecular players mediated by BZD9L1 is not fully understood. This study aimed to uncover the mechanisms involved in BZD9L1-mediated cytotoxicity based on previous and new findings for the prediction and identification of related pathways and key molecular players. BZD9L1-regulated candidate targets (RCTs) were identified using a range of molecular, cell-based and biochemical techniques on the HCT 116 cell line. BZD9L1 regulated major cancer pathways including Notch, p53, cell cycle, NFκB, Myc/MAX, and MAPK/ERK signalling pathways. BZD9L1 also induced reactive oxygen species (ROS), regulated apoptosis-related proteins, and altered cell polarity and adhesion profiles. In silico analyses revealed that most RCTs were interconnected, and were involved in the modulation of catalytic activity, metabolism and transcription regulation, response to cytokines, and apoptosis signalling pathways. These RCTs were implicated in p53-dependent apoptosis pathway. This study provides the first assessment of possible associations of molecular players underlying the cytotoxic activity of BZD9L1, and establishes the links between RCTs and apoptosis through the p53 pathway.

Adhesion Molecules in Non-melanoma Skin Cancers: A Comprehensive Review

Basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) are the most frequently diagnosed cancers, generating significant medical and financial problems. Cutaneous carcinogenesis is a very complex process characterized by genetic and molecular alterations, and mediated by various proteins and pathways. Cell adhesion molecules (CAMs) are transmembrane proteins responsible for cell-to-cell and cell-to-extracellular matrix adhesion, engaged in all steps of tumor progression. Based on their structures they are divided into five major groups: cadherins, integrins, selectins, immunoglobulins and CD44 family. Cadherins, integrins and CD44 are the most studied in the context of non-melanoma skin cancers. The differences in expression of adhesion molecules may be related to the invasiveness of these tumors, through the loss of tissue integrity, neovascularization and alterations in intercellular signaling processes. In this article, each group of CAMs is briefly described and the present knowledge on their role in the development of non-melanoma skin cancers is summarized.

Dietary flavonoid myricetin inhibits invasion and migration of radioresistant lung cancer cells (A549-IR) by suppressing MMP-2 and MMP-9 expressions through inhibition of the FAK-ERK signaling pathway

Myricetin is a commonly found dietary flavonoid. In the present study, we investigated the effects of myricetin on migration and invasion of radioresistant lung cancer cells (A549-IR). Transcriptome analysis of A549-IR cells identified several differentially expressed genes (DEGs) in A549-IR cells compared to parental A549 cells. Functional enrichment analysis revealed that most of the DEGs were linked with PI3K-AKT signaling, proteoglycans, focal adhesion, and ECM-receptor interactions. A549-IR cells demonstrated enhanced migratory potential with increased expression of vimentin, snail and slug, and reduced expression of E-cadherin. A549-IR cells exposed to myricetin displayed reduced migration and suppressed MMP-2 and MMP-9 expression. Notably, myricetin inhibited the phosphorylation of focal adhesion kinase (FAK) and altered the F-actin/G-actin ratio in A549-IR cells, without modulation of EMT markers. These findings suggest that myricetin can inhibit migration of A549-IR cells by suppressing MMP-2 and MMP-9 expressions through inhibition of the FAK-ERK signaling pathway.

Multilayered Cultures of NSCLC cells grown at the Air-Liquid Interface allow the efficacy testing of inhaled anti-cancer drugs

Evidence supports the advantages of inhalation over other drug-administration routes in the treatment of lung diseases, including cancer. Although data obtained from animal models and conventional in vitro cultures are informative, testing the efficacy of inhaled chemotherapeutic agents requires human-relevant preclinical tools. Such tools are currently unavailable. Here, we developed and characterized in vitro models for the efficacy testing of inhaled chemotherapeutic agents against non-small-cell lung cancer (NSCLC). These models recapitulated key elements of both the lung epithelium and the tumour tissue, namely the direct contact with the gas phase and the three-dimensional (3D) architecture. Our in vitro models were formed by growing, for the first time, human adenocarcinoma (A549) cells as multilayered mono-cultures at the Air-Liquid Interface (ALI). The in vitro models were tested for their response to four benchmarking chemotherapeutics, currently in use in clinics, demonstrating an increased resistance to these drugs as compared to sub-confluent monolayered 2D cell cultures. Chemoresistance was comparable to that detected in 3D hypoxic tumour spheroids. Being cultured in ALI conditions, the multilayered monocultures demonstrated to be compatible with testing drugs administered as a liquid aerosol by a clinical nebulizer, offering an advantage over 3D tumour spheroids. In conclusion, we demonstrated that our in vitro models provide new human-relevant tools allowing for the efficacy screening of inhaled anti-cancer drugs.

Membranous staining of β-catenin and E-cadherin expression in patients with gastric cancer

BACKGROUND

β-catenin and E-cadherin are adhesion molecules that promote metastatic potential through epithelial-mesenchymal transition (EMT). Although they have not been extensively studied in gastric cancers, they represent potential testable prognostic markers.

METHODS

We explored the association between the immunohistochemical expression of these markers and clinicopathologic parameters by retrospectively reviewing 205 cases of gastric cancer from tissue microarrays (TMA). A method was developed to evaluate for membranous staining of β-catenin and E-cadherin using grading criteria that characterized both the intensity of staining and the percentage of cells with loss of staining.

RESULTS

Weak membranous expression of E-cadherin and β-catenin were associated with worse overall survival (p<0.05). Abnormal expression of E-cadherin and β-catenin were significantly associated with each other (p<0.01). Loss of and/or weak membranous staining for both E-cadherin and β-catenin was significantly associated with advanced cancer stage T2-T4 (versus stage T1, p<0.05) and tumors that are negative for H pylori infection (p<0.05). In addition, loss of and/or weak membranous staining for β-catenin was significantly associated with poorly differentiated tumors (p<0.05), diffuse Lauren-type gastric tissue (p=0.02), and tumors with a significantly higher rate of lymphovascular invasion (p=0.02).

CONCLUSION

Loss of/weak membranous expression of both E-cadherin and β-catenin was associated with poorer overall survival rates and clinicopathologic parameters that indicated an aggressive clinical behavior. β-catenin shows significant associations with more clinical parameters, making it a better biomarker than E-cadherin. In our multivariate analysis, weak intensity of staining of β-catenin was an independent prognostic factor for survival and may be a useful immunohistochemical prognostic marker for patients with gastric cancer.

Armc8 regulates the invasive ability of hepatocellular carcinoma through E-cadherin/catenin complex

Armc8 (armadillo-repeat-containing protein 8) was proved to promote disruption of E-cadherin complex through regulating α-catenin degradation. In this study, we investigated Armc8 expression in hepatocellular carcinoma using immunohistochemistry (IHC). The positive rate of Armc8 expression in hepatocellular carcinoma was 53.9 % and higher than that in normal hepatic tissues (9.2 %) (p < 0.05). Clinicopathological analysis shows that Armc8 expression in hepatocellular carcinoma was significantly associated with larger tumor size (≥5 cm), multiple tumor numbers, higher pathological grade (media and poor), advanced TNM stages (II/III), and advanced BCLC stages (B/C). Western blot study also detected higher Armc8 expression in hepatocellular carcinoma cells including HepG2, HCC97L, and SMMC-7721 than in human hepatic cell Bel-7402. We further use specific small interfering RNAs (siRNAs) to knock down Armc8 expression in HepG2 cells and found that knockdown of Armc8 expression significantly inhibited the invasive ability of HepG2 cells. Downregulation of Armc8 expression significantly upregulated α-catenin, β-catenin, and E-cadherin expression in HepG2 cells. Immunofluorescent study shows that knockdown of Armc8 expression restored E-cadherin expression in membrane of HepG2 cells. These results indicate that Armc8 may be a potential cancer marker in hepatocellular carcinoma and may regulate cancer invasion through E-cadherin/catenin complex.

Altered expression of epithelial-to-mesenchymal transition proteins in extraprostatic prostate cancer

Epithelial to mesenchymal transition (EMT) of cancer cells involves loss of epithelial polarity and adhesiveness, and gain of invasive and migratory mesenchymal behaviours. EMT occurs in prostate cancer (PCa) but it is unknown whether this is in specific areas of primary tumours. We examined whether any of eleven EMT-related proteins have altered expression or subcellular localisation within the extraprostatic extension component of locally advanced PCa compared with other localisations, and whether similar changes may occur in in vitro organotypic PCa cell cultures and in vivo PCa models. Expression profiles of three proteins (E-cadherin, Snail, and α-smooth muscle actin) were significantly different in extraprostatic extension PCa compared with intra-prostatic tumour, and 18/27 cases had an expression change of at least one of these three proteins. Of the three significantly altered EMT proteins in pT3 samples, one showed similar significantly altered expression patterns in in vitro organotypic culture models, and two in in vivo Pten-/- model samples. These results suggest that changes in EMT protein expression can be observed in the extraprostatic extension component of locally invasive PCa. The biology of some of these changes in protein expression may be studied in certain in vitro and in vivo PCa models.

Ex vivo bio-compatibility of honey-alginate fibrous matrix for HaCaT and 3T3 with prime molecular expressions

Honey's inherent compositional diversity, bio-compatibility and time tested therapeutic efficacy, especially in tissue repair as a topical agent, attract researchers towards harnessing its biomaterial potential particularly in developing matrix for tissue engineering applications. Hence, this study fabricates fibrous mat from optimum honey-alginate formulation and alginate solution using wet spinning technology. The physical and morphological properties of the scaffolds are assessed and finally their comparative biological performances are evaluated through in vitro studies on adherence, viability and prime molecular expression of HaCaT and 3T3 cells. The honey-alginate scaffold demonstrates better performance than that of alginate in terms of cellular adherence, viability and proper expression of cell-cell adhesion molecule (E-cadherin) and prime molecules of extra cellular matrix (Collagen I and III) by HaCaT and 3T3 respectively.

Armc8 expression was elevated during atypia-to-carcinoma progression and associated with cancer development of breast carcinoma

Armadillo repeat-containing protein 8 (Armc8) is a key factor to regulate cell membrane adhesion complex through promoting α-catenin degradation. However, its expression and function in human malignant tumors are largely unknown. Here, we present our study investigating Armc8 expression in tumor and non-tumor breast tissues including 45 normal epithelia, 53 lesions of hyperplasia with or without dysplasia, 22 benign tumors, and 92 carcinomas including 28 carcinomas in situ and 64 infiltrating carcinomas using immunohistochemistry (IHC) and Western blotting study. Armc8 expression was detected mainly in the cytoplasm with occasional membrane immunostaining. The positive rate of Armc8 expression in normal breast epithelia (8.9%, four out of 45) was very low. No significant difference was found between Armc8 expression in usual ductal hyperplasia (UDH) (11.1%, two out of 18), benign breast tumors including intraductal papilloma (10.0%, one out of 10) and fibroadenoma (8.3%, one out of 12), and normal breast epithelia (p>0.05). Elevated expression of Armc8 was found in breast epithelia with dysplasia (24.0%, six out of 25) compared to that in normal breast epithelia, UDH, and benign breast tumors (p<0.05). Armc8 expression in breast carcinoma including breast carcinoma in situ (10/28, 35.7%), infiltrating ductal carcinoma (60.7%, 34/56), and infiltrating lobular carcinoma (50.0%, 4/8) was higher than that in normal breast epithelia, UDH, benign breast tumors, and breast epithelia with dysplasia (p<0.05). The highest expression of Armc8 was found in infiltrating breast carcinoma (59.4%, 38/64) compared to all the other breast tissues. Higher Armc8 expression was found to be linked to lymph node metastasis and advanced tumor-node-metastasis (TNM) stages (III+IV) in infiltrating breast carcinoma (p<0.05). We further confirmed Armc8 expression in breast epithelial cell line MCF10A and breast carcinoma cell lines including MCF-7, MDA-MB-231, and ZR751 using Western blotting and immunofluorescent study. These results indicate that the elevated expression of Armc8 may be involved in carcinogenesis including atypia-to-carcinoma progression and cancer development of breast carcinoma.

Adhesion molecules affected by treatment of lung cancer cells with epidermal growth factor

Lung cancer is one of the leading causes of death in the world. Some tumor events are attributed to an important group of molecules (cadherins and integrins). We evaluated the interactions of cell adhesion molecules in cell lines from lung cancer. Two lung cancer cell lines were nonmetastatic (H358 and H441) and two were metastatic (H1299 and H292). All cell lines were treated with epidermal growth factor (EGF), and Western blot analysis was performed to assess the interactions between these proteins. The bronchoalveolar cells H358 showed the three analyzed proteins: E-cadherin, β-catenin, and p120 catenin. The adenocarcinoma cells H441 did not present p120 catenin, and carcinoma cells did not show E-cadherin (H1299) or p120 catenin (H292). FAK (pTyr925) was dephosphorylated in adenocarcinoma cells H441, absent in carcinoma cells H1299, and upregulated in the other carcinoma cells H292. p130Cas showed no difference when the cell lines were treated with EGF for 30 min; it was absent in the metastatic carcinoma cells H1299. Paxillin was dephosphorylated in adenocarcinoma cells H441 and also absent in other metastatic carcinoma cells H292. Vinculin showed the same results, and talin was downregulated in adenocarcinoma cells H441 when the cells were treated with EGF. Rap1 was downregulated and PYK2 was upregulated in the same cell line. Our data help to comprehend the mechanism involved in cell migration to the blood and metastasis generation. In conclusion, the expression patterns of cell-cell adhesion were not affected by EGF treatment but it affected cell-extracellular matrix adhesion.

Prognostic and risk factors in patients with locally advanced cutaneous squamous cell carcinoma of the trunk and extremities

55 patients with advanced cutaneous squamous cell carcinoma (CSCC) of the trunk and extremities were studied. A Tissue Microarray was constructed using immunohistochemistry to quantify expression of the HER family, E-cadherins, and podoplanin. Clinical and histopathological factors related to lymph node metastasis and prognosis were also established. Primary tumor positivity was 25.5% for EGFR, 87.3% for HER-3, and 48.1% for HER-4. Metastases were positive for EGFR in 41.7%, for HER-3 in 83.3%, and HER-4 in 43.5%. HER-2 was negative in all samples. Membrane E-cadherin and cytoplasmic E-cadherin were positive in 47.3% and 30.2% of primary tumors and 45.5% and 27.3% of metastases, respectively. Podoplanin was positive in 41.8% of primary tumors and 41.7% of metastases. Intratumoral lymphocytic infiltrate was associated with lymph node metastasis. Patients with T3 tumors had better cancer-specific survival (CSS) than those with T4 tumors; patients with no lymph node involvement had better CSS than patients with N1 tumors. Undifferentiated tumors and hyperexpression of podoplanin were negative prognostic indicators on multivariate analysis.

The value of E-cadherin/beta-catenin expression in imprints of NCSLC: relationship with clinicopathological factors

Metastasis is specific for malignant tumors and its control is one of the most important problems in the design of therapies for cancer patients. Loss or reduction of E-cadherin expression and/or beta-catenin expression plays a casual role in tumor progression and metastasis and is associated with poor prognosis. The purpose of the study is to investigate the expression of E-cadherin and beta-catenin and their significance as independent prognostic markers in imprints of resected nonsmall cell lung cancer (NSCLC). Imprint smears from 70 patients who underwent surgical lung resection for primary carcinoma were studied. As control group was used imprints of physiological tissues. Histologically 47 (67.1%) of the tumors were squamous cell carcinomas and 23 (32.9%) were adenocarcinomas. Tumors stage was I in 29 (41.4%), II in 13 (18.6%), III in 24 (34.3%) and IV in 4 (5.7%). Positive expression for E-cadherin was observed in 44.29% of malignant smears vs 85.71% for control group (P = 0.011). For beta-catenin, positive expression was observed in 42.86% malignant cases vs 85.71% for control group (P = 0.008). Positive expression of E-cadherin and beta-catenin was observed in moderate and well differentiated tumors (P < 0.0001 for both respectively). Positive E-cadherin and beta-catenin expression was observed in 70.6% and 76.5% of the cases with negative lymphnode metastasis (P < 0.0001 for both respectively). There was no statistically significant association between histological type, tumor stage, pleural invasion, tumor size (P > 0.05 for all) and E-cadherin/beta-catenin expression.Reduced E-cadherin or beta-catenin negative expression relates to dedifferentiation and progression of NSCLC.

Immunohistochemical assessment of E-cadherin and beta-catenin in trichofolliculomas and trichoepitheliomas

BACKGROUND

Trichofolliculomas and trichoepitheliomas are benign skin neoplasms originating from hair follicle cells. They result from defects in the signaling pathways that regulate hair follicle morphogenesis and regeneration. Thus they seem to be an excellent model of these processes. It is known that the E-cadherin/beta-catenin system of adhesion molecules plays a crucial role in the maintenance of tissue architecture.

AIM

The aim of the present study was to investigate their involvement in benign hair follicle tumor development.

METHODS

Semiquantitative intensity of expression were examined in formalin-fixed and paraffin-embedded tissue sections of 53 trichoepitheliomas, 15 trichofolliculomas and 19 normal skin samples by indirect immunohistochemistry.

RESULTS

The intensity of E-cadherin/beta-catenin expression in tumor cells did not differ from controls. However, normal hair follicles cells exhibited membranous E-cadherin/beta-catenin expression, whereas both types of tumors, particularly trichoepitheliomas, showed E-cadherin/beta-catenin expression with a predominantly cytoplasmic localization.

CONCLUSIONS

We suggest that this dystopic distribution of the E-cadherin/beta-catenin complex in hair follicle tumor cells may be a marker of cell-cell adhesion disruption which may contribute to the tumor formation.

Improvement in predicting tumorigenic phenotype of androgen-insensitive human LNCaP prostatic cancer cell subline in recombination with rat urogenital sinus mesenchyme

Hormone-refractory prostate cancer, a heterogeneous disease, has varying degrees of androgen sensitivity. To understand the physiological changes in the hormone-refractory state, the present study used a lineage-derived androgen receptor (AR)-positive, androgen-insensitive prostate cancer cell line and evaluated the tumorigenic phenotype, focusing on tumor-stromal interactions in vivo. First, tumorigenic differences of cancer cells alone were examined in an androgen-insensitive AR-positive LNCaP subline, AIDL, compared with those of the androgen-sensitive AR-positive parental LNCaP and the androgen-insensitive AR-negative PC-3 cells transplanted into subcutaneous, sub-renal and prostatic orthotopic graft sites. Next, cancer cells were recombined with rat urogenital sinus mesenchyme (rUGM) to simulate the tumor-stromal microenvironment. Tumors of AIDL and LNCaP without stromal components both formed well-defined globular tumors and contained large blood-filled areas, with no significant difference in tumor growth or histopathology regardless of the cell line's androgen sensitivity or graft site. In contrast, tumors of AIDL and LNCaP recombined with rUGM both showed reduction of blood-filled areas in the tumors and increased tumor growth compared with cancer cells alone. Tumors of AIDL + rUGM recombinants were approximately three times as large as those of LNCaP + rUGM recombinants, whereas tumors of AIDL and LNCaP without rUGM were not different in size. In addition to the tumor size, cell proliferation (Ki-67 labeling index) in tumors of AIDL + rUGM recombinants was significantly higher than that in tumors of LNCaP + rUGM recombinants. Immunoreactivities of AR, E-cadherin and beta-catenin were decreased in AIDL + rUGM recombinants relative to AIDL alone and LNCaP + rUGM recombinants. These results demonstrated that tumorigenic features of androgen-insensitive AR-positive prostate cancer cells could be significantly influenced by rUGM. Therefore, this in vivo recombination model with rUGM may be useful in developing new treatment strategies.

Nuclear E-cadherin immunoexpression: from biology to potential applications in diagnostic pathology

E-cadherin is a well-recognized molecule that is important in cell adhesion. Its abrogation has been linked to increased invasiveness in several malignancies. The normal immunohistochemical localization of E-cadherin is the cell membrane, however, both cytoplasmic and nuclear immunostaining has been reported. Loss of membrane staining and/or nuclear staining for E-cadherin is seen in 100% of cases of solid pseudopapillary tumors (SPTs) of the pancreas. In the context of SPT, E-cadherin staining is of diagnostic use. Nuclear staining has been seen in cases of pancreatic neuroendocrine tumors, Merkel cell carcinomas, clear cell renal cell carcinoma, esophageal squamous carcinoma, colorectal and gastric cancer, and synovial sarcoma. The difference in the staining patterns seen (complete loss vs. nuclear staining) is due to the type of E-cadherin antibody used. Antibodies recognizing the extracellular domain show loss of E-cadherin staining in SPT, whereas the antibody to the cytoplasmic domain results in nuclear staining in all cases of SPT. Therefore, E-cadherin staining is of diagnostic use in the immunohistochemical work-up of SPT. Nuclear E-cadherin staining of pancreatic neuroendocrine tumors identified a subset of cases with more aggressive potential, whereas nuclear staining of clear cell renal cancers identified a subset of tumors with a better prognosis. The exact mechanism by which E-cadherin enters the nucleus is not known but it is likely that it is closely related to several partner molecules such as beta-catenin, p120, and presenilin-1.

Distinct expression patterns of E-cadherin and beta-catenin in signet ring cell carcinoma components of primary pulmonary adenocarcinoma

CONTEXT

E-Cadherin and beta-catenin complexes have been suggested to have critical roles in cancer development and progression. Primary signet ring cell carcinoma (SRCC) of the lung is a rare variant of pulmonary adenocarcinoma, and E-cadherin and beta-catenin expressions of this tumor have not been documented, to our knowledge.

OBJECTIVE

To characterize the E-cadherin and beta-catenin expressions in SRCC of the lung.

DESIGN

An immunohistochemical evaluation of E-cadherin and beta-catenin expressions in 10 cases of SRCC of the lung, 10 cases of conventional pulmonary adenocarcinoma, 10 cases of gastric SRCC, and 10 cases of colorectal SRCC was performed.

RESULTS

Membranous E-cadherin and beta-catenin expressions were frequently reduced or absent in all types of tumors tested. Aberrant E-cadherin localization and nuclear beta-catenin accumulation were frequently found in gastric (6/10 and 5/10, respectively) and colorectal (7/10 and 9/ 10, respectively) SRCCs, whereas SRCC of the lung rarely showed aberrant E-cadherin localization (1/10) or nuclear beta-catenin accumulation (0/10).

CONCLUSIONS

Signet ring cell carcinoma of the lung rarely showed aberrant E-cadherin localization or beta-catenin nuclear accumulation, which are frequent events in gastric and colorectal SRCCs. These results suggest that the biologic roles of E-cadherin and beta-catenin complexes in SRCC of the lung differ from their roles in gastric or colorectal SRCCs.

Pseudomonas aeruginosa pyocyanin inactivates lung epithelial vacuolar ATPase-dependent cystic fibrosis transmembrane conductance regulator expression and localization

Pseudomonas aeruginosa (PA) is a major pathogen causing morbidity and ultimately mortality in patients afflicted with cystic fibrosis (CF) lung disease. One important virulence factor, pyocyanin (PCN), is a blue, redox-active compound that is secreted in such copious amounts by PA in the CF lungs that it determines the colour of expectorated sputum. In this study, we discovered that physiological concentrations of PCN inactivate the airway epithelial vacuolar ATPase, resulting in reduced expression and trafficking of the cystic fibrosis transmembrane conductance regulator in cultured lung and primary nasal epithelial cells. Our study supports the notion that PCN contributes significantly to the pathogenesis of CF and other bronchiectasis patients infected by PA.

E-cadherin expression pattern in primary colorectal carcinomas and their metastases reflects disease outcome

AIM: To investigate the changes that occur in E-cadherin expression during the process of metastasis in colorectal cancer.

METHODS: E-cadherin expression was detected by immunohistochemistry and two indices of expression were calculated which reflected the level of expression and the locations (membrane and cytoplasm). Univariate and multivariate survival analyses were used to assess the value of these two E-cadherin indices as predictors of both disease-free (DFS) and disease-specific (DSS) survival.

RESULTS: E-cadherin membrane index (MI), but not cytoplasmic index (CI), was significantly higher in primary tumors than their metastases (P = 0.0001). Furthermore, both primary tumor MI and CI were higher among the patients who developed subsequent metastasis (P = 0.022 and P = 0.007, respectively). Interestingly, both indices were higher in liver metastase compared to other anatomic sites (MI, P = 0.034 and CI, P = 0.022). The CI of the primary tumors was a significant predictor of DFS (P = 0.042, univariate analysis), with a strong inverse correlation between CI and DFS (P = 0.006, multivariate analysis). Finally, the MI of primary tumor proved to be a significant independent predictor of DSS, with higher indices being associated with a more favorable outcome (P = 0.016).

CONCLUSION: Examination of E-cadherin expression and distribution in colorectal tumors can be extremely valuable in predicting disease recurrence. The observation that aberrant cytoplasmic expression of E-cadherin can predict disease recurrence is obviously of great importance for both patients and clinicians, and significantly affects decisions concerning the therapy and management of the patients.

Microsatellite analysis of the APC gene and immunoexpression of E-cadherin, catenin, and tubulin in esophageal squamous cell carcinoma

The histological features that accompany the development and progression of solid tumors are known to be controlled by a distinct cascade of molecular events. One such event is the inactivation of tumor suppressor genes, such as the adenomatous polyposis coli (APC) gene. Disruption of the cadherin-catenin cell adhesion complex also plays a role in the initial steps of cancer invasion and metastasis whereas alterations in cell structural molecules, such as tubulin, may contribute to the cancer phenotype. The understanding of the status of these molecules in ESSC may provide novel markers that could impact on management of the disease. The present study examined alterations in the microsatellite sequence of the APC gene via fluorescent-based polymerase chain reaction in 100 cases of primary esophageal squamous cell carcinoma. In addition, the expression of E-cadherin, alpha- and beta-catenin, and alpha- and beta-tubulin was analyzed using immunohistochemistry. These data were then statistically compared with each other as well as the relevant clinicopathologic data. Although the APC markers (D5S210, D5S346, D5S299, and D5S82) tested did show an overall high frequency of allelic imbalance/loss of heterozygosity (62.48%) and microsatellite instability (41.27%), they did not show prognostic significance in the study cohort and were not correlated with the immunohistochemical data. The tubulin proteins showed no significant change in expression in the tumor tissue The decreased immunoreactivity of E-cadherin was statistically correlated with the presence of lymph node metastases (P = .0180). Although alpha- and beta-catenin as well as E-cadherin showed no direct prognostic value, E-cadherin may warrant further investigation as an indirect prognostic indicator by allowing more accurate prediction of lymph node metastases.

Reduced p120ctn expression correlates with poor survival in patients with adenocarcinoma of the gastroesophageal junction

BACKGROUND AND OBJECTIVES

P120-catenin (p120ctn) is a member of the E-cadherin-catenin cell-cell adhesion complex. Impairment of one or more of the components of this complex is associated with tumorigenesis. The role of p120ctn in malignancy is not clear yet. We studied the in vivo expression and cellular localization of p120ctn in adenocarcinomas of the gastroesophageal junction.

METHODS

Immunohistochemical staining for p120ctn was performed on 96 tumor samples, 20 cases of Barretts metaplasia and 13 lymph node metastases. The relationship with pathological characteristics and patient survival was also assessed.

RESULTS

Loss of normal surface p120ctn expression was found in 4/20 (20%) Barretts metaplasia, in 65/96 (68%) tumors, and 11/13 (85%) lymph node metastases. Nuclear immunoreactivity for p120ctn was seen in five tumors. Loss of normal expression of p120ctn was associated with a higher tumor grade (P < 0.0001) but not with pTNM-stage. Reduced expression of p120ctn was correlated with poor survival (P = 0.0002). Cox regression analysis showed that p120ctn is an independent prognostic marker.

CONCLUSIONS

Abnormal p120ctn expression is frequently seen in adenocarcinomas of the gastroesophageal junction, and may be a useful as a prognostic marker in these tumors.

3D culture model and computer-assisted videomicroscopy to analyze migratory behavior of noninvasive and invasive bronchial epithelial cells

To date, most of the studies in the field of cell migration have been applied to two-dimensional (2D) models. To mimic the three-dimensional (3D) conditions similar to those observed in vivo during tumor invasion, we developed a 3D model of cell migration in which cells were embedded in a collagen I matrix placed in a double-compartment chamber. Using time-lapse videomicroscopy and interactive cell tracking in a four-dimensional data set, we determined the cell trajectories and their migration kinetics. We compared the 2D and 3D migratory behavior of a noninvasive cell line (16HBE) with the migratory behavior of an invasive cell line (BZR). Our results show that the 3D migration kinetics of the noninvasive cell line were lower than the migration kinetics of the invasive cell line. In contrast, in 2D models, no significant difference was observed between the two cell lines. To validate our 3D model, we further investigated the effect of epidermal growth factor (EGF), a promoter of tumor cell motility and invasion on the noninvasive cell line (16HBE). EGF increased significantly the migration kinetics of the noninvasive cell line. Our results show that the 3D model of cell migration allowed us to differentiate the migratory behavior of invasive and noninvasive cells and that such a model can help in the development of molecular targeted therapy as it approaches the in vivo conditions.

Correlation of gamma-catenin expression with good prognosis in medulloblastomas

OBJECT

Medulloblastoma is a malignant cerebellar tumor of childhood and is difficult to cure due to frequent cerebrospinal fluid dissemination. Amplification of the c-myc gene (4%) and messenger (mRNA) overexpression (50%) are known to be adverse prognostic indicators. Because mRNA overexpression cannot be explained by gene amplification alone, mechanisms other than gene amplification are postulated. Molecules on the Wnt signal pathway in primary tumors were examined.

METHODS

Immunohistochemical and cytogenetic examinations of beta- and gamma-catenin, c-myc, N-myc, and cyclin D1 in 24 primary medulloblastomas were conducted, and their clinical relevance was evaluated. Cytoplasmic/membranous staining of beta- and gamma-catenin was detected in 19 (79%) and nine (37%) cases, respectively, and nuclear expression of cyclin D1 and c-myc was detected in six (25%) and 21 (83%) cases, respectively. The expression levels of gamma-catenin in Western blot analysis and immunohistochemistry were similar. By differential polymerase chain reaction, c-myc and N-myc were amplified separately in two large cell/anaplastic medulloblastomas. No cyclin D1 amplification, or beta- or gamma-catenin mutations were found. Kaplan-Meier analysis revealed no dissemination at diagnosis (Chang Grade M0) and gamma-catenin expression was correlated with good prognosis (p = 0.0002 and 0.003, respectively). Expression of gamma-catenin was also significant in the M0 group (p = 0.022). Expression of cyclin D1 showed a trend toward adverse outcome (p = 0.057) and all patients in whom cyclin D1 expression was found died of disease.

CONCLUSIONS

Expression of gamma-catenin is of great prognostic value and its immunohistochemistry may be useful for further stratification of treatment. Cyclin D expression may have the potential to be an adverse prognostic indicator.

The E-cadherin–β-catenin complex and its implication in lung cancer progression and prognosis

The E-cadherin–β−catenin complex plays a pivotal role in epithelial cell–cell adhesion and in the maintenance of differentiated adult epithelia. Perturbation of its expression or function is widely involved in tumor progression and metastasis. Recent years have seen a rapid expansion in the understanding of the biology and the clinical relevance of the E-cadherin adhesion complex in human lung cancer. During human lung cancer progression genomic, transcriptionnal and post-transcriptionnal alterations of the E-cadherin–β-catenin adhesion system are implicated and comprise deletion of the chromosomic region 3p21 that comprise the locus of the gene encoding β-catenin, transcriptionnal downregulation of E-cadherin, cytoplasmic redistribution, phosphorylation of both proteins and proteolysis of E-cadherin. E-cadherin-inactivating mutations and oncogenic-activating mutation of β-catenin are not reported.

E-Cadherin and beta-Catenin expression in early stage cervical carcinoma: a tissue microarray study of 147 cases

Background

The disruption of intercellular adhesions is an important component of the acquisition of invasive properties in epithelial malignancies. Alterations in the cell-cell adhesion complex, E-Cadherin/β-Catenin, have been implicated in the oncogenesis of carcinomas arising from various anatomic sites and have been correlated with adverse clinico-pathologic parameters. In this study, the authors investigated the immunohistochemical expression of E-Cadherin and β-Catenin in a cohort of early stage cervical cancers to determine its prognostic significance and to investigate differences between the three major histological subtypes.

Patients and methods

A tissue microarray of 147 cases of FIGO stage 1A and 1B cervical carcinomas [96 squamous cell carcinomas (SCC), 35 adenocarcinomas (AC), 12 adenosquamous carcinomas (ASQ), 4 miscellaneous types] was constructed from our archived surgical pathology files and stained with monoclonal antibodies to E-Cadherin and β-Catenin. Cases were scored by multiplying the intensity of staining (1 to 3 scale) by the percentage of cells stained (0–100%) for a potential maximum score of 300. For both markers, "preserved" expression was defined as bright membranous staining with a score of 200 or above. "Impaired" expression included any of the following: negative staining, a score less than 200, or exclusively cytoplasmic or nuclear delocalization.

Results

Impaired expression of β-Catenin was found in 85.7%, 66.7%, & 58.3% of AC, SCC & ASQ respectively. Impaired expression of E-Cadherin was found in 94.3%, 86.5% & 100% of cases of AC, SCC, & ASQ respectively. The differences between the histologic subtypes were not significant. For the whole cohort, a comparsion of cases showing impaired versus preserved of E-Cadherin and β-Catenin expression showed no significant differences with respect to recurrence free survival, overall survival, patient age, histologic grade, and frequency of lymphovascular invasion or lymph node involvement. There was no correlation between the status of both markers for all three histological subtypes (overall spearman correlation co-efficient r = 0.12, p = 0.14)

Conclusion

Impairment of E-Cadherin and β-Catenin expression is very frequent in early stage cervical cancers, and alterations in the E-Cadherin/β-Catenin cell adhesion complex are therefore likely involved in the pathogenesis of cervical carcinomas even at their earliest stages. None of the three major histological subtypes of cervical carcinoma (SCC, ADCA, ADSQ) is significantly more likely than the others to show impairment in E-Cadherin and β-Catenin expression. Overall, the expression of both markers does not significantly correlate with clinico-pathological parameters of prognostic significance.

Alteration of the E-cadherin/beta-catenin cell adhesion system is common in pulmonary neuroendocrine tumors and is an independent predictor of lymph node metastasis in atypical carcinoids

BACKGROUND

To the authors' knowledge, little is known regarding the role of E-cadherin/beta-catenin system dysregulation in pulmonary neuroendocrine tumors.

METHODS

E-cadherin and beta-catenin immunoreactivity was evaluated in 10 hyperplastic neuroendocrine tumorlets and 210 neuroendocrine tumors, including 96 typical carcinoids (CTs), 35 atypical carcinoids (ACTs), 49 large cell neuroendocrine carcinomas (LCNECs), and 30 small cell lung carcinomas (SCLCs).

RESULTS

Normal and hyperplastic bronchial neuroendocrine cells expressed E-cadherin/beta-catenin with an orderly distribution along the cell membrane. Neuroendocrine tumors retained beta-catenin expression in all tumors and E-cadherin in most tumors, with the exception of 2% of LCNECs, 3% of SCLCs and 9% of ACTs. E-cadherin showed a prevalent membrane-associated, linear immunoreactivity in CTs, whereas membrane-disarrayed and cytoplasmic staining was seen in most ACTs, LCNECs, and SCLCs (P < 0.001). beta-Catenin exhibited similar immunoreactivity patterns according to tumor type and a close association with E-cadherin subcellular distribution (P < 0.001). Nuclear accumulation of beta-catenin was found only in seven LCNECs and in two SCLCs. In ACTs, disarrayed immunoreactivity for E-cadherin and/or beta-catenin was associated with a nontrabecular growth pattern, altered expression of the cell-motility marker fascin, and lymph node metastases. Furthermore, a disarrayed E-cadherin distribution pattern was associated with the pathologic lymph node classification and the number of involved lymph nodes. Multivariate analysis confirmed that a disarrayed E-cadherin or beta-catenin pattern was an independent predictor of lymph node metastases in patients with ACT.

CONCLUSIONS

The subcellular compartmentalization of the E-cadherin/beta-catenin complex was altered in pulmonary neuroendocrine tumors. This likely affects the tumor growth pattern and cell motility of ACT and was correlated with the occurrence of lymph node metastases.

Prognostic value of E-cadherin immunoexpression in patients with primary ovarian carcinomas

PURPOSE

To analyse the negative versus positive immunoexpression of E-cadherin in patients with primary ovarian carcinomas, and determine its significance in relation to clinicopathological features, overall and recurrence-free survival (RFS).

PATIENTS AND METHODS

The protein expression of E-cadherin was immunohistochemically evaluated in formalin-fixed, paraffin-embedded samples in 104 patients with primary ovarian carcinomas. The clinicopathological factors studied were age, FIGO staging, histological type, tumour differentiation, the appearance of the ovarian capsule, peritoneal implants and residual tumour after cytoreductive surgery. Overall survival and RFS were evaluated using the Kaplan-Meier method, and multivariate analysis was completed using the Cox regression model.

RESULTS

Of the 104 carcinomas, negative E-cadherin immunoexpression was observed in seven (7%) cases, and positive immunoexpression in 97 (93%). E-cadherin categorised into negative versus positive expression did not associate with any of the established clinicopathological parameters. However, negative E-cadherin expression significantly predicted a poorer overall survival when compared with positive expression (P=0.006). In the multivariate analyses, negative E-cadherin and the presence of residual tumour after cytoreductive surgery were independent prognostic factors for survival (P=0.014 and P=0.034, respectively).

CONCLUSIONS

The presence of residual tumour after primary cytoreductive surgery and negative E-cadherin expression seem to be useful markers in patients with ovarian carcinomas likely to have an unfavourable clinical outcome. The assessment of E-cadherin immunoreactivity may be a useful prognostic indicator in ovarian cancer, complementary to established prognostic factors.

Expression of e-cadherin and beta-catenin in cutaneous squamous cell carcinoma and its precursors

The E-cadherin-beta-catenin complex regulates the architectural integrity of epithelia by mediating intercellular adhesion. Down-regulation of its expression may contribute to invasion and metastatic behavior of carcinoma cells. Several studies demonstrated an abnormal expression of E-cadherin, beta-catenin, or both in various carcinomas, including non-melanoma skin cancer. The aim of the present study was to investigate the involvement of E-cadherin-catenin adhesion system in the progression of human cutaneous squamous cell carcinoma (SCC). For that purpose, sections from normal skin, skin showing solar elastosis (SE), solar keratosis (SK), and SCC were stained with monoclonal antibodies against E-cadherin and beta-catenin. Evaluation of the staining results was performed using a semi-quantitative method in which pattern and intensity of staining, percentage of positive cells, and cytoplasmic staining were evaluated. Normal skin and skin showing mild and moderate solar elastosis strongly expressed membranous E-cadherin and beta-catenin. E-cadherin expression was progressively reduced in the epidermis of skin with severe solar elastosis through solar keratosis to SCC. The same phenomenon was observed for beta-catenin starting from solar keratosis. In some cases of SCC, additional cytoplasmic staining was observed. We found no correlation between E-cadherin and beta-catenin expression and tumor differentiation or between SCC from sun-exposed and sun-protected skin. Statistical analysis revealed correlation between expression of both E-cadherin and beta-catenin and the morphology of the lesion. These results support a gradual evolution from severely sun-damaged skin to SCC, not only on a morphologic level, but also at the molecular level.

E-cadherin-beta-catenin adhesion complex in neuroendocrine tumors of the lung: a suggested role upon local invasion and metastasis

Dysfunction or loss of the intercellular adhesion complex E-cadherin-beta-catenin is frequent in non-small cell lung carcinomas in which E-cadherin and beta-catenin loss has been considered to be a molecular marker of tumor progression and poor prognosis. With an aim of evaluating the expression of the E-cadherin-beta-catenin complex and its prognostic role in neuroendocrine tumors (NET) of the lung, immunohistochemical analysis was performed in 102 NET, including 16 low-grade typical carcinoids, 8 intermediate-grade atypical carcinoids, 37 large-cell neuroendocrine carcinomas (LCNEC), and 41 small-cell lung carcinomas, both high-grade tumors. Impaired E-cadherin expression (loss or cytoplasmic delocalization) was observed in 80 (78%) of 102 samples, and impaired beta-catenin expression was noted in 74 (72%) of 102 cases. The impaired expression of E-cadherin and beta-catenin was observed with a higher frequency in high-grade tumors (87% and 83%, respectively) than in carcinoids (50% and 37%, respectively; P < 0.0001). Impaired expression of the E-cadherin and beta-catenin molecules also correlated with lymph node metastasis (P = 0.0001 and P = 0.0005, respectively) and with advanced stage disease (P < 0.0001 for both factors). Moreover, impaired E-cadherin expression directly correlated with an extensive disease in carcinoids and in LCNEC (P = 0.02 and P = 0.04, respectively) and with node metastasis in LCNEC (P = 0.01). Levels of E-cadherin and beta-catenin were correlated with each other, consistent with an internal regulatory loop. Our results indicate that down-regulation of the E-cadherin-beta-catenin complex plays a role in NET progression.

SMAGP, a new small trans-membrane glycoprotein altered in cancer

Using the Affymetrix array technology, we previously identified an EST strongly expressed in several metastatic cell lines. In the present study, we cloned the corresponding cDNA that encodes a new glycoprotein composed of 97 amino acids and containing a trans-membrane domain. Therefore, we named it SMAGP for Small trans-Membrane And Glycosylated Protein. SMAGP is strongly conserved during evolution. It is expressed by normal epithelia of various organs, the protein being notably localized to the lateral face of the plasma membrane of cohesive well-polarized epithelial cells. In addition, SMAGP contains binding domains for the protein 4.1 and the PDZ domain of MAGUK proteins. Similar protein features are observed in several cell-surface proteins involved via ternary complexes in intercellular processes leading to cytoskeleton assembly as well as intracellular signalling. Thus, SMAGP might similarly be involved in a scaffolding protein complex, and therefore participate in the epithelium organization or in subsequent functions. Immunohistochemical data obtained using human breast, colon and lung cancer samples sustain this hypothesis since they showed that, in both primary tumours and metastases, reduced expression and/or cytoplasmic redistribution of SMAGP is superimposable with low histological tumour differentiation features, namely a lack of epithelial cell polarity and disorganized tissue phenotype.

Altered expression of adhesion molecules and epithelial-mesenchymal transition in silica-induced rat lung carcinogenesis

Loss of the epithelial phenotype and disruption of adhesion molecules is a hallmark in the epithelial-mesenchymal transition (EMT) reported in several types of cancer. Most of the studies about the relevance of adhesion and junction molecules in lung cancer have been performed using established tumors or in vitro models. The sequential molecular events leading to EMT during lung cancer progression are still not well understood. We have used a rat model for multistep lung carcinogenesis to study the status of adherens and tight junction proteins and mesenchymal markers during EMT. After silica-induced chronic inflammation, rats sequentially develop epithelial hyperplasia, preneoplastic lesions, and tumors such as adenocarcinomas and squamous cell carcinomas. In comparison with normal and hyperplastic bronchiolar epithelium and with hyperplastic alveolar type II cells, the expression levels of E-cadherin, alpha-catenin and beta-catenin were significantly reduced in adenomatoid preneoplastic lesions and in late tumors. The loss of E-cadherin in tumors was associated with its promoter hypermethylation. alpha- and beta-catenin dysregulation lead to cytoplasmic accumulation in some carcinomas. No nuclear beta-catenin localization was found at any stage of any preneoplastic or neoplastic lesion. Zonula occludens protein-1 was markedly decreased in 66% of adenocarcinomas and in 100% squamous cell carcinomas. The mesenchymal-associated proteins N-cadherin and vimentin were analyzed as markers for EMT. N-cadherin was de novo expressed in 32% of adenocarcinomas and 33% of squamous cell carcinomas. Vimentin-positive tumor cells were found in 35% of adenocarcinomas and 88% of squamous cell carcinomas. Mesenchymal markers were absent in precursor lesions, both hyperplastic and adenomatoid. The present results show that silica-induced rat lung carcinogenesis is a good model to study EMT in vivo, and also provide in vivo evidence suggesting that the changes in cell-cell adhesion molecules are an early event in lung carcinogenesis, while EMT occurs at a later stage.

Reduced expression of E-cadherin in human non-small cell lung carcinoma

PURPOSE

E-cadherin, a calcium-dependent cell to cell adhesion molecule, plays a key role in the maintenance of tissue integrity. Reduction or loss of E-cadherin has been reported to have a role in the development of human malignancies. The expression of E-cadherin was analyzed in human non-small cell lung carcinoma (NSCLC) to elucidate the role in pulmonary carcinogenesis and determine the relationship with several clinicopathological factors and the prognosis.

MATERIALS AND METHODS

Sixty five human cases of NSCLC were evaluated by immunohistochemical analysis for the expression of E-cadherin. The immunostaining results for E-cadherin were semiquantitatively interpreted, as preserved and reduced, in the tumor tissues. The E-cadherin expression was analyzed in relation to several clinicopathological data and the survival. The cell proliferation index of the tumors was evaluated by immunostaining with the Ki-67 antigen.

RESULTS

Reduced E-cadherin expression was found in 51 cases of NSCLC tissues (78.4%) compared to that in the normal controls. Reduced E-cadherin expression was significantly correlated with male smokers and squamous cell type of the cancer, but not with histological grade, TNM stage and survival. The E-cadherin expression showed a weak inverse relationship with the proliferative activity of tumor cells, which was measured using the Ki-67 antigen.

CONCLUSION

Our data support the hypothesis that reduced E-cadherin expression may play a role in the pathogenesis of human NSCLC, which might be associated with the control for cell proliferation.

Activation of beta-catenin provides proliferative and invasive advantages in c-myc/TGF-alpha hepatocarcinogenesis promoted by phenobarbital

Previously, we have found that phenobarbital (PB) enhanced cell survival and facilitated tumor growth in our c-myc/transforming growth factor (TGF)-alpha transgenic mouse model of liver cancer. Given that PB selectively promoted initiated cells harboring beta-catenin mutations during chemically induced hepatocarcinogenesis and that Wnt/beta-catenin signaling is involved in both anti-apoptotic and proliferative processes, we now have extended our analysis to investigate whether promotion by PB affects the occurrence of beta-catenin mutations in c-myc/TGF-alpha-driven tumors. The frequency of beta-catenin activation as judged by somatic mutations and/or nuclear localization was significantly increased in hepatocellular carcinomas (HCCs) from c-myc/TGF-alpha mice treated with PB (15/28; 53.6%) as compared with that in control HCCs (2/28; 7.1%). Furthermore, an intact beta-catenin locus was detected in all neoplasms following PB treatment, whereas 57.1% (16/28) of malignant tumors from c-myc/TGF-alpha untreated mice displayed loss of heterozygosity at the beta-catenin locus. Strikingly, in the majority of PB-treated HCCs beta-catenin nuclear localization was limited to small cells with high nuclear/cytoplasmic ratio forming an invasion front (NAinv). beta-Catenin NAinv cells showed cytoplasmic redistribution of E-cadherin associated with intense mucin 1 and matrilysin immunostaining, suggesting their invasive phenotype. All beta-catenin-positive HCCs displayed increased proliferation and tumor size, but no difference in the apoptotic rate when compared with beta-catenin negative tumors. These findings show that PB treatment positively selects for a cell population displaying activation of beta-catenin in c-myc/TGF-alpha HCCs. beta-Catenin activation confers additional growth and invasive advantages in a model of liver cancer already accelerated by synergistic activity of the c-myc and TGF-alpha transgenes.

E-Cadherin mediates MMP down-regulation in highly invasive bronchial tumor cells

The disorganization of E-cadherin/catenin complexes and the overexpression of matrix metalloproteinases (MMPs) are frequently involved in the capacity of epithelial cells to acquire an invasive phenotype. The functional link between E-cadherin and MMPs was studied by transfecting invasive bronchial BZR tumor cells with human E-cadherin cDNA. Using different in vitro (cell dispersion, modified Boyden chamber) and in vivo assays (human airway epithelial xenograft), we showed that E-cadherin-positive clones displayed a decrease of invasive abilities. As shown by immunoprecipitation, the re-expressed E-cadherin was able to sequestrate one part of free cytoplasmic beta-catenin in BZR cells. The decrease of beta-catenin transcriptional activity in E-cadherin-transfected clones was demonstrated using the TOP-FLASH reporter construct. Finally, we observed a decrease of MMP-1, MMP-3, MMP-9, and MT1-MMP, both at the mRNA and at the protein levels, in E-cadherin-positive clones whereas no changes in MMP-2, TIMP-1, or TIMP-2 were observed when compared with control clones. Moreover, zymography analysis revealed a loss of MMP-2 activation ability in E-cadherin-positive clones treated with the concanavalin A lectin. These data demonstrate a direct role of E-cadherin/catenin complex organization in the regulation of MMPs and suggest an implication of this regulation in the expression of an invasive phenotype by bronchial tumor cells.

Upregulation of MMPs by soluble E-cadherin in human lung tumor cells

Loss of E-cadherin/catenin mediated cell-cell adhesion and overexpression of matrix metalloproteinases (MMPs) are largely involved in tumor invasion. It has been recently shown that high levels of a soluble 80 kDa fragment of E-cadherin, resulting from a cleavage by MMPs, are found in serum and in urine from cancer patients. Additionally, this soluble E-cadherin (sE-CAD) promotes cell invasion into chick heart and into collagen type I gels. The aim of our study was to examine the mechanism of sE-CAD-induced cell invasion. Since MMPs play a crucial role in invasion, we looked for induction of MMPs by sE-CAD in noninvasive human lung tumor cells 16HBE. An induction of MMP-2, MMP-9 and MT1-MMP expression was observed both at the mRNA and at the protein level in the presence of sE-CAD (in conditioned medium form or in E-cadherin HAV peptide form). No induction of MMP-1, -3 and -7 or variation of the levels of their inhibitors, TIMP-1 and TIMP-2, were detected. The biologic relevance of the sE-CAD-induced MMP upregulation was tested by demonstrating that sE-CAD promotes in vitro cell invasion in a modified Boyden chamber assay. These data provide new insight into mechanisms of tumor invasion by ectodomain shedding of the cell-cell adhesion molecule E-cadherin.

Neural-cadherin expression associated with angiogenesis in non-small-cell lung cancer patients

An immunohistochemical analysis for E(epithelial)-cadherin and N(neural)-cadherin expression in relation to tumour angiogenesis was performed in 150 patients with nonsmall cell lung cancer (NSCLC). In all, 71 carcinomas (47.3%) were E-cadherin-negative. Epithelial-cadherin-negative tumours had lymph node metastases significantly more frequently than E-cadherin-positive tumours (P=0.0100). On the other hand, 46 carcinomas (30.7%) were N-cadherin-positive. Regarding tumour vascularity, there was no significant correlation between E-cadherin expression and tumour vascular. In contrast, the frequency of hypervascular tumours was significantly higher for N-cadherin-positive carcinomas than for N-cadherin-negative carcinomas (P=0.0373). Regarding prognosis, the 5-year survival rate of patients with E-cadherin-negative NSCLCs was significantly lower than that of patients with E-cadherin-positive NSCLCs (P=0.0146). In contrast, of the patients with large cell carcinomas, the 5-year survival rate of patients with N-cadherin-positive tumours was significantly lower than that of patients with N-cadherin-negative tumours (P=0.0013). A multivariate analysis demonstrated that E-cadherin status (P=0.0339) and tumour vascularity (P=0.0295) were significant indicators for survival. In conclusion, E-cadherin expression and tumour vascularity are significant prognostic factors of NSCLC patients. Furthermore, N-cadherin expression is associated with tumour angiogenesis, and its expression is one of prognostic factors of patients with large cell carcinomas. Thus, N-cadherin also might play a specific role in undifferentiated large cell carcinomas.

Calcium-dependent phosphorylation processes control brain aromatase in quail

Increased gene transcription activated by the binding of sex steroids to their cognate receptors is one important way in which oestrogen synthase (aromatase) activity is regulated in the brain. This control mechanism is relatively slow (hours to days) but recent data indicate that aromatase activity in quail preoptic-hypothalamic homogenates is also rapidly (within minutes) affected by exposure to conditions that enhance Ca2+-dependent protein phosphorylation. We demonstrate here that Ca2+-dependent phosphorylations controlled by the activity of multiple protein kinases including PKC, and possibly also PKA and CAMK, can rapidly down-regulate aromatase activity in brain homogenates. These phosphorylations directly affect the aromatase molecule itself. Western blotting experiments on aromatase purified by immunoprecipitation reveal the presence on the enzyme of phosphorylated serine, threonine and tyrosine residues in concentrations that are increased by phosphorylating conditions. Cloning and sequencing of the quail aromatase identified a 1541-bp open reading frame that encodes a predicted 490-amino-acid protein containing all the functional domains that have been previously described in the mammalian and avian aromatase. Fifteen predicted consensus phosphorylation sites were identified in this sequence, but only two of these (threonine 455 and 486) match the consensus sequences corresponding to the protein kinases that were shown to affect aromatase activity during the pharmacological experiments (i.e. PKC and PKA). This suggests that the phosphorylation of one or both of these residues represents the mechanism underlying, at least in part, the rapid changes in aromatase activity.

Proliferation, but not apoptosis, is associated with distinct beta-catenin expression patterns in non-small-cell lung carcinomas: relationship with adenomatous polyposis coli and G(1)-to S-phase cell-cycle regulators

beta-catenin (beta-cat) is a versatile component of homotypic cell adhesion and signaling. Its subcellular localization and cytoplasmic levels are tightly regulated by the adenomatous polyposis coli (APC) protein. Mutations in beta-cat (exon 3) or APC (MCR) result in beta-cat aberrant overexpression that is associated with its nuclear accumulation and improper gene activation. Data from experimental models have shown that beta-cat overexpression has a multitude of effects on cell-cycle behavior. In many of these aspects its function depends on major G(1) phase regulators. To the best of our knowledge, most of these issues have never been addressed concurrently in tumors. For this reason we investigated in a panel of 92 non-small-cell lung carcinomas, beta-cat and APC expression, and their relationship with cell-cycle kinetics (PI and AI) and ploidy status. Moreover, the above correlations were examined in relation to the main G(1)/S-phase checkpoint regulators. Four beta-cat immunohistochemical expression patterns [membranous (11.1%), membranous-cytoplasmic (54.3%), cytoplasmic (9.9%), cytoplasmic-nuclear (24.7%)] and three APC immunohistochemical expression patterns [cytoplasmic (37.7%), cytoplasmic-nuclear (58%), nuclear (4.3%)] were observed, which were further confirmed by Western blot analysis on subcellular fractions in representative samples. The frequent presence of beta-cat in the cytoplasm is an indication of aberrant expression, whereas membranous and nuclear localization were inversely related. Absence of mutations in beta-cat (exon 3) and APC (MCR) suggest that beta-cat destruction mechanisms may be functional. However, expression analysis revealed attenuated levels for APC, indicating a residual ability to degrade beta-cat. Decreased levels were associated with loss of heterozygosity at the APC region in 24% of the cases suggesting that additional silencing mechanisms may be involved. Interestingly, the 90-kd APC isoform associated with apoptosis, was found to be the predominant isoform in normal and cancerous lung tissues. The most important finding in our study, was the correlation of nuclear beta-cat immunohistochemical localization with increased proliferation, overexpression of E2F1 and MDM2, aberrant p53, and low expression of p27(KIP), providing for the first time in vivo evidence that beta-cat-associated proliferation correlates with release of E2F1 activity and loss of p53- and p27(KIP)-dependent cell-cycle checkpoints. Loss of these checkpoints is accompanied by low levels of APC, which possibly reflects a diminished ability to degrade beta-cat. Taken together our data indicate that cases with nuclear beta-cat immunohistochemical expression represent a subset of non-small-cell lung carcinomas that have gained an increased proliferation advantage in contrast to the other beta-cat immunohistochemical expression profiles.

Cell migration and proliferation are not discriminatory factors in the in vitro sociologic behavior of bronchial epithelial cell lines

A model of cellular cohesion has been developed, which permits the in vitro study of the spatial and temporal distribution of two human bronchial cell lines. The spatial distribution of cells in culture was characterized from videomicroscopic recordings and analyzed using an algorithmic program of cellular sociology based on the use of three geometrical models: Voronoï's partition, Delaunay's graph, the and minimum spanning tree (MST). The results obtained suggested that the manner of cellular cohesiveness could be used to differentiate between the organizational behaviors of the cell lines: non-invasive 16HBE14o- cells rapidly formed clusters with a cohesive organization, whereas invasive BZR cells remained isolated and were characterized by a non-cohesive organization. Videomicroscopic and image analysis techniques also demonstrated that cell migration and proliferation are not discriminatory factors for explaining differences in the spatial organizations of the two cell lines. We concluded that the random nature of cell movement combined with the cell adhesion capacity are determinant factors in cell cluster formation.

Immunohistochemical detection of E-cadherin, alpha- and beta-catenins in papillary thyroid carcinoma

E-cadherin and catenins play a major role in neoplastic cell behavior as a suppressor of invasion and/or metastasis. The aim of this study was to determine E-cadherin, alpha-catenin and beta-catenin expressions in papillary thyroid carcinoma (PTC) and to correlate the results of expression to initial clinicopathological parameters and clinical outcome. Forty-one cases (mean age 37.3 +/- 11.2 yr) with PTC were studied. Patients were followed-up with a mean period of 47.6 +/- 27.0 months. A retrospective immunohistochemical analysis of E-cadherin, alpha-catenin and beta-catenin was performed on paraffin-embedded tissue sections. Tissues from ten patients with benign goiter were used as controls. E-cadherin, alpha- and beta-catenin immunoreactivities were found in 80% (33/41), 76% (31/41) and 97% (40/41) of patients respectively. No correlation was found between E-cadherin, alpha- and beta-catenin immunoreactivities and sex, local invasion or lymphatic spread at the time of initial examination. Distant metastases and/or local recurrences developed in 6 patients during follow-up. Recurrences/metastases developed both E-cadherin, alpha- and beta-catenin positive and negative primary tumors. Disease-free survival curves according to Kaplan-Meier analysis and log-rank test did not show any significant differences between E-cadherin, alpha- and beta-catenin positive and negative patients. According to our findings, E-cadherin, alpha- and beta-catenin expressions may not add any valuable information to the follow-up in a subgroup of PTC patients with a relatively benign course.

High-throughput tissue microarray analysis used to evaluate biology and prognostic significance of the E-cadherin pathway in non-small-cell lung cancer

PURPOSE

E-cadherin (E-cad) and its associated intracellular molecules, catenins, are critical for intercellular epithelial adhesion and are often expressed in non-small-cell lung carcinomas (NSCLCs). We constructed tissue microarrays (TMAs) to investigate the expression of cadherins and catenins and their prognostic significance in NSCLC.

PATIENTS AND METHODS

Tumor tissue samples from 193 patients with stages I to III NSCLC were obtained from the University of Colorado Cancer Center and Johns Hopkins Medical Institutions. Viable tumor was sampled in triplicate for the TMAs, and slides were stained by immunohistochemistry with antibodies against E-cad, N-cadherin, alpha (alpha)-, beta (beta)-, and gamma (gamma)-catenin, p120, p27, and adenomatous polyposis coli (APC) gene product. Clinical data were collected by the tumor registries. Patients were followed for a median period of 51 months (range, 18 to 100 months).

RESULTS

Absent or severely reduced membranous expression for E-cad, alpha-, beta-, and gamma-catenin, and p120 were observed in 10%, 17%, 8%, 31%, and 61% of the cases, respectively. Tumor cell dedifferentiation correlated with reduced expression for E-cad, beta-catenin, gamma-catenin, and p120 in squamous cell carcinomas but not in adenocarcinomas. There was an inverse correlation between nodal metastasis and expression of E-cad and gamma-catenin. Besides the traditional clinical prognostic variables, E-cad and alpha-, beta-, and gamma-catenin expression were of positive prognostic value in univariate survival analyses. In multivariate analysis, E-cad expression was the only independent prognostic factor for survival in addition to age, node status, tumor status, and pathologic surgical margins.

CONCLUSION

Reduced expression of E-cad and catenins is associated with tumor cell dedifferentiation, local invasion, regional metastasis, and reduced survival in NSCLC. E-cad is an independent prognostic factor for NSCLC survival.

The E-cadherin cell-cell adhesion complex and lung cancer invasion, metastasis, and prognosis

BACKGROUND

Lung cancer is the most common cause of cancer deaths in the western world. Progress in treatment results has been limited, and the prognosis is poor with a 5-year survival less than 15%. Based on new developments in molecular biology, our knowledge about lung carcinogenesis and mechanisms for invasion and metastasis has expanded and may in the future lead to more specific targeted therapies and better prognosis. The E-cadherin-catenin complex is critical for intercellular adhesiveness and maintenance of normal and malignant tissue architecture. Reduced expression of this complex in malignant disease is associated with tumour invasion, metastasis, and unfavorable prognosis.

METHODS

This review is based on search in the Medline database from 1991 to 2001. We have reviewed the relevance of the E-cadherin-catenin adhesion complex in malignancy in general and lung cancer in particular. Furthermore, its role as target for specific therapy is discussed.

RESULTS

Available data indicate that alterations of proteins involved in the E-cadherin-catenin complex are early incidents in cancer development. Reduced or altered expression of one or more of the components in this complex is associated with extended invasive and progressive behavior of cancer cells. Consistently, the E-cadherin-catenin complex appears to be increasingly delicate with regard to cancer prognosis. beta-Catenin, one of the components of the adhesion complex, also plays a significant role in cell signal transduction, gene activation, apoptosis inhibition, and increased cellular proliferation and migration.

CONCLUSION

Inactivation of the E-cadherin-catenin adhesion complex, induced by genetic and epigenetic events, plays a significant role in multistage carcinogenesis, and seems to be associated with dedifferentiation, local invasion, regional metastasis, and reduced survival in lung cancer.

FGF-1 and FGF-2 regulate the expression of E-cadherin and catenins in pancreatic adenocarcinoma

E-cadherin is a transmembrane protein that mediates Ca2+-dependent cell-cell adhesion and is implicated in a number of biologic processes, including cell growth and differentiation, cell recognition and cell sorting during development. We have previously demonstrated that both cell-cell adhesion and invasion are modulated by fibroblast growth factor (FGF)-1 and FGF-2 in a panel of pancreatic adenocarcinoma cell lines (BxPc3, T3M4 and HPAF). Here, we examine further the role of FGFs in the expression and activation of the E-cadherin/catenin system. We demonstrate that both FGF-1 and FGF-2 upregulate E-cadherin and beta-catenin at the protein level in the BxPc3 and HPAF cell lines and modestly in T3M4 cells. FGF-1 and FGF-2 facilitate the association of E-cadherin and alpha-catenin with the cytoskeleton, as demonstrated by the increase in the detergent-insoluble fraction of E-cadherin in BxPc3 and HPAF cells. Since the correct function of the E-cadherin/catenin complex requires its association with the cytoskeleton, our data suggest that FGF-1 and FGF-2 contribute to the integrity and thus the function of the complex. Furthermore, FGFs facilitate the assembly of the E-cadherin/catenin axis. The effect is associated with elevation of tyrosine phosphorylation of E-cadherin, alpha-catenin, beta-4051 mu-catenin and gamma-catenin, but not p120ctn. These findings indicate that the E-cadherin/catenin system is a target of the FGF/FGFR system and that coordinated signals from both systems may determine the ultimate biologic responses.

Expression of E-Cadherin and Lymph Node Metastasis in Resected Non–Small-Cell Lung Cancer

This study was conducted to clarify the relationship between E-cadherin expression on tumor and lymph node metastasis as well as its prognostic roles in resected non-small-cell lung cancer. Two hundred forty-nine patients, who underwent surgical resection (stage I-IIIA), were examined. Paraffin-embedded sections of the primary tumors in all cases and of the metastatic lymph nodes in stage IIIA disease were stained with a monoclonal antibody against E-cadherin. Decreased expression of E-cadherin correlated with pathologic stage, tumor size, lymph node metastasis, and histological grade. The 5-year survival rate of E-cadherin-negative patients with stage IIIA disease was significantly lower than that of E-cadherin-positive patients. Multivariate analysis in stage IIIA disease indicated that E-cadherin was an independent prognostic factor. In the patients with clinical N0 tumors, the frequency of pathological N2 tumors was significantly higher in cases where the primary tumor was recognized as E-cadherin expression negative than in cases where the primary tumor was recognized as positive. Decreased E-cadherin expression showed correlation with presence of lymph node metastasis in resected non-small-cell lung cancer and with the prognosis of patients with stage IIIA disease.

Quantitative cell dispersion analysis: new test to measure tumor cell aggressiveness

Tumor progression requires the dispersion of epithelial cells from neoplastic clusters and cell invasion of adjacent stromal connective tissue. Aiming at demonstrating the precise relationships between cell dispersion and cell invasion, related respectively to expression of E-cadherin/catenin complex and matrix metalloproteinases (MMPs), we developed an original in vitro model of cell dispersion analysis. Our study reports the validation of this model that allowed us to analyze and quantify the cell cohesion level by means of time-lapse videomicroscopy and computer analysis based on the observation of spatial and temporal cell distribution. Our model was able to distinguish 2 groups among different human bronchial and mammary epithelial cells previously characterized for the expression of E-cadherin/catenin complex and MMPs and their invasive capacity in the Boyden chamber assay. The first group (16HBE14o(-), MCF-7, T47D) that expressed membranous E-cadherin and beta-catenin, and was negative for MMP-2 expression and non-invasive, displayed a highly cohesive pattern corresponding to a cluster spatial distribution. The second group (Beas2B, BZR, BZR-T33, MDA-MB-231, MDA-MB-435, BT549 and HS578T) that was invasive and showed lack of expression of E-cadherin and a cytoplasmic redistribution of beta-catenin, displayed a dispersed pattern corresponding to a random spatial distribution. Downregulation of E-cadherin by a blocking antibody induced a more random distribution. Conversely, expression of E-cadherin by cDNA transfection induced a cluster distribution. Moreover, tumor cell lines that co-expressed MT1-MMP and MMP-2 (Beas2B, BZR, BZR-T33, MDA-MB-435, BT549 and HS578T) showed a more dispersed pattern than tumor cell lines that did not express MMP-2 (MDA-MB-231). In conclusion, we demonstrated that the spatial group behavior of cell lines, i.e., their cohesion/dispersion ability, reflects their invasive properties. Thus, this model of cell dispersion analysis may represent a new test to measure tumor cell aggressiveness.

Genetic alteration of the beta-catenin gene (CTNNB1) in human lung cancer and malignant mesothelioma and identification of a new 3p21.3 homozygous deletion

The beta-catenin gene (CTNNB1) has been shown to be genetically mutated in various human malignancies. To determine whether the beta-catenin gene is responsible for oncogenesis in thoracic malignancies, we searched for the mutation in 166 lung cancers (90 primary tumors and 76 cell lines), one blastoma and 10 malignant mesotheliomas (two primary tumors and eight cell lines). Among the lung cancers, including 43 small cell lung cancers (SCLCs) and 123 non-small cell lung cancers (NSCLCs), we identified four alterations in exon 3, which is the target region of mutation for stabilizing beta-catenin. One primary adenocarcinoma had a somatic mutation from C to G, leading to an amino acid substitution from Ser to Cys at codon 37. Among the cell lines, SCLC NCI-H1092 had a mutation from A to G, leading to an Asp to Gly substitution at codon 6, NSCLC HCC15 had a mutation from C to T, leading to a Ser to Phe substitution at codon 45, and NSCLC NCI-H358 had a mutation from A to G, leading to a Thr to Ala substitution at codon 75. One blastoma also had a somatic mutation from C to G, leading to a Ser to Cys substitution at codon 37. Among the 10 malignant mesotheliomas, we identified a homozygous deletion in the NCI-H28 cell line. Cloning of the rearranged fragment from NCI-H28 indicated that all the exons except exon 1 of the beta-catenin gene are deleted and that the deletion junction is 13 kb downstream from exon 1. Furthermore, Northern blot analysis of 26 lung cancer and eight mesothelioma cell line RNAs detected ubiquitous expression of the beta-catenin messages except NCI-H28, although Western blot analysis showed that relatively less amounts of protein products were expressed in some of lung cancer cell lines. Our findings suggest that the beta-catenin gene is infrequently mutated in lung cancer and that the NCI-H28 homozygous deletion of the beta-catenin gene might indicate the possibility of a new tumor suppressor gene residing in this region at 3p21.3, where various types of human cancers show frequent allelic loss.

Expression of the E-cadherin-catenin complex in lung neuroendocrine tumours

Neuroendocrine tumours (NETs) of the lung represent a wide spectrum of phenotypically distinct entities, with differences in tumour progression and aggressiveness. The redistribution and/or the loss of various cell adhesion molecules, such as the E-cadherin-catenin complex, play a predominant role in carcinogenesis and in tumour invasion. Moreover, mutations in exon 3 of the beta-catenin gene, the adenomatous polyposis coli (APC) gene or the E-cadherin genes were previously found to result in intracytoplasmic and/or nuclear beta-catenin protein accumulation, activating nuclear transcription of target genes involved in tumour progression. In the present study, the distribution of the components of this E-cadherin-catenin complex has been investigated by immunohistochemistry and an attempt has been made to correlate the abnormal expression pattern with the eventual detection of mutations in the corresponding genes. This study included 27 primary NETs of the lung, with nine typical carcinoids (TCs), three atypical carcinoids (ACs), and 15 large cell neuroendocrine carcinomas (LCNECs). The E-cadherin-catenin complex remained expressed in most of these lung tumours, but with a cytoplasmic and/or nuclear redistribution of beta-catenin, E-cadherin, and alpha-catenin; abnormal positive immunoreactivity was observed in 24 (88.9%), in 21 (80.8%), and in 20 (76.9%) NETs, respectively. In the great majority of cases, there was a good correlation between the expression of these three proteins, but no significant association with histological classification or TNM stage. Thus, E-cadherin-complex redistribution cannot be considered a prognostic marker in NET of the lung. Of particular interest was the frequent focal beta-catenin nuclear immunostaining (55.5% in total), which was also unrelated to histological type or TNM stage. However, this study failed to detect any mutation in exon 3 of the beta-catenin gene, in the APC gene or in the E-cadherin gene. These data suggest another mechanism of regulation of beta-catenin in these tumours.

E-cadherin expression associated with differentiation and prognosis in patients with non-small cell lung cancer

BACKGROUND

E-Cadherin plays a major role in maintaining the intercellular junctions in epithelial tissues. The reduction of E-cadherin expression in cancer cells may be associated with tumor differentiation, metastasis, and a poor prognosis.

METHODS

Immunohistochemistry for E-cadherin expression was performed on 109 tumors from patients with non-small cell lung cancer who underwent operations.

RESULTS

With respect to membranous immunostaining, 57 carcinomas were E-cadherin-positive, 39 carcinomas E-cadherin-reduced, and 13 carcinomas E-cadherin-negative. The percentage of poorly differentiated tumors in the impaired E-cadherin expression group was significantly higher than that in the E-cadherin-positive group (p = 0.005). Furthermore, the frequency of lymph node metastases in tumors with impaired E-cadherin expression was significantly higher than that in the E-cadherin-positive tumors (p = 0.011). A Cox regression analysis revealed that E-cadherin expression was a significant factor in the prediction of survival for patients with non-small cell lung cancer (p = 0.002).

CONCLUSIONS

E-Cadherin expression was associated with tumor differentiation, lymph node metastasis, and prognosis in patients with non-small cell lung cancer.

Altered distribution of beta-catenin, and its binding proteins E-cadherin and APC, in ulcerative colitis-related colorectal cancers

The beta-catenin pathway plays a central role in transcriptional signaling and cell-cell interactions in colonic epithelium. Alterations of the expression of beta-catenin, and its binding partners E-cadherin and the adenomatous polyposis coli protein (APC), are frequent events in sporadic colorectal cancer. Ulcerative colitis (UC)-related cancers originate in a field of chronic inflammation and therefore may have different alterations in the beta-catenin pathway than sporadic cancers. To test this hypothesis, expression and subcellular localization of beta-catenin, E-cadherin, and APC were detected by immunohistochemistry in paraffin sections from 33 UC-related and 42 sporadic colorectal cancers. Although beta-catenin and E-cadherin expression were predominantly limited to the lateral cell membrane in normal colonic epithelium, both tumor groups showed an overall shift from membranous to cytoplasmic expression for these proteins. An increase in nuclear localization of beta-catenin and a decrease in cytoplasmic APC expression also were seen in both cancer groups compared with normal epithelium. Abnormal beta-catenin expression was more closely linked to E-cadherin alterations in UC-related cancers than in sporadic cancers. In contrast, abnormal beta-catenin expression was more closely linked to APC alterations in sporadic cancers than in UC-related cancers. These data suggest that alterations of the beta-catenin pathway are important in both UC-related and sporadic colorectal cancers. However, differences in the expression patterns of beta-catenin, E-cadherin, and APC between UC-related and sporadic colorectal cancers suggest that the specific alterations in this pathway may differ in these two cancer groups.

Expression of CD44v6 but not E-cadherin or beta-catenin influences prognosis in primary pulmonary adenocarcinoma

Primary pulmonary adenocarcinoma was studied, looking for relationships between the expression of cell adhesion molecules (CAMs) E-cadherin, beta-catenin and CD44v6, and clinicopathological tumour parameters and patient post-operative survival. Formalin-fixed, paraffin-embedded tissue from 120 primary lung adenocarcinomas, including 23 poorly differentiated tumours, 17 of probable bronchial origin, and 29 with a prominent bronchioloalveolar pattern, together with nodal metastatic tumour from 34 of these patients was stained using monoclonal antibodies and immunohistochemistry. Sections were scored either high level (>10% cells positive) or low level (<10% positive). High level expression of CD44v6 was retained in 28.4% (34/120) of tumours, while high levels of E-cadherin (57.5%, 69/120) and beta-catenin (80. 8%, 97/120) were more frequent. For all CAMs, staining levels did not correlate with nodal status, stage or tumour type. The apical or basal staining seen in normal bronchial and alveolar epithelium was often seen in papillary, glandular, and bronchioloalveolar areas of tumour, while solid invasive tumour more often showed pericellular staining. When the staining for each CAM in 34 nodal metastases was compared with that in the corresponding primary tumour, a high degree of concordance was found, with no tendency for metastases to show less staining than the primary tumour. Expression of E-cadherin and beta-catenin in the primary tumour had no influence on post-operative survival, but patients whose tumours had low level CD44v6 expression had a poorer post-operative survival than those with high levels of CD44v6 (p=0.0014 for all patients, p=0.0012 for stage I patients only). In primary pulmonary adenocarcinoma, the levels of expression of E-cadherin, beta-catenin, and CD44v6 are not associated with lymph node metastases or tumour stage but the staining pattern is associated with tumour morphology. Low levels of CD44v6 expression predict a poor post-operative survival, independently of stage, while there is no such relationship with the expression of E-cadherin or beta-catenin.