Distinct cadherin profiles in special variant carcinomas and other tumors of the breast

Cadherin switching in oral squamous cell carcinoma: A clinicopathological study

Background and aim

Oral squamous cell carcinoma (OSCC) is one of the most common malignancies worldwide as it represents the sixth most common cancer. Numerous molecular mechanisms have been explained to regulate OSCC progression, including epithelial-mesenchymal transition (EMT). Cadherin switching is the pivotal process that controls EMT in which E-cadherin reduces while N-cadherin elevates. This work aimed to clarify the role of cadherin switching in OSCC.

Material and methods

Thirty paraffin-embedded tissue blocks of OSCC including six cases with lymph node metastasis were subjected to immunohistochemical staining using antibodies against E&N-cadherins. Cell cultures were performed using OSCC cell lines (SCC-15/SCC-25) from the human tongue. F-12K medium (Kaighn's Modification of Ham's F12 Medium) was added as EMT inducing media. E&N-cadherin mRNA gene expression levels were detected by real time-polymerase chain reaction (RT-PCR).

Results

Cadherin switching through N-cadherin elevation and E-cadherin reduction was evaluated at the histopathologic level in primary and metastatic OSCC as well as at the genetic level within OSCC cell culture. Cadherin switching showed a significant correlation between E&N-cadherins at different histopathological grades of OSCC and in metastatic OSCC. Moreover, the level of mRNA gene expression of E&N-cadherins in human 15 SCC and 25 SCC cell lines with EMT-inducing media exhibited a significant correlation.

Conclusions

Cadherin switching is a crucial event in the EMT process. It may be used as a significant tool in the study of OSCC progression. Cadherin switching plays a significant role in the invasion and metastasis of OSCC.

Adhesion of Gastric Cancer Cells to the Enteric Nervous System: Comparison between the Intestinal Type and Diffuse Type of Gastric Cancer

Background: Gastric cancer (GC) is the third leading cause of cancer-related deaths worldwide. The enteric nervous system (ENS) has been suggested to be involved in cancer development and spread. Objective: To analyze the GC cell adhesion to the ENS in a model of co-culture of gastric ENS with GC cells. Methods: Primary culture of gastric ENS (pcgENS), derived from a rat embryo stomach, was developed. The adhesion of GC cells to pcgENS was studied using a co-culture model. The role of N-Cadherin, a cell-adhesion protein, was evaluated. Results: Compared to intestinal-type GC cells, the diffuse-type GC cancer cells showed higher adhesion to pcgENS (55.9% ± 1.075 vs. 38.9% ± 0.6611, respectively, p < 0.001). The number of diffuse-type GC cells adherent to pcgENS was significantly lower in neuron-free pcgENS compared to neuron-containing pcgENS (p = 0.0261 and 0.0329 for AGS and MKN45, respectively). Confocal microscopy showed that GC cells adhere preferentially to the neurons of the pcgENS. N-Cadherin blockage resulted in significantly decreased adhesion of the GC cells to the pcgENS (p < 0.01). Conclusion: These results suggest a potential role of enteric neurons in the dissemination of GC cells, especially of the diffuse-type, partly through N-Cadherin.

Pterostilbene-isothiocyanate inhibits breast cancer metastasis by selectively blocking IKK-β/NEMO interaction in cancer cells

Metastasis, the main cause of breast cancer-associated fatalities, relies on many regular pathways involved in normal cell physiology and metabolism, thus, making it challenging to identify disease-specific therapeutic target(s). Chemically synthesized anti-metastatic agents are preferred for their fast and robust actions. However, these agents have adverse side effects, thus, increasingly favouring the identification of phytocompounds as suitable alternatives. Resveratrol and pterostilbene have long been established as potent anti-cancer agents. Earlier studies from our laboratory documented the anti-cancer activities associated with pterostilbene-isothiocyanate (PTER-ITC), a derivative of pterostilbene. The current study focuses on evaluating the anti-metastatic property of PTER-ITC and the underlying mechanism, by employing in silico, in vitro, and in vivo approaches. The significant anti-metastatic activity of PTER-ITC was observed in vitro against breast cancer metastatic cell line (MDA-MB-231) and in vivo in the 4T1 cell-induced metastatic mice model. Epithelial-mesenchymal transition (EMT), a hallmark of metastasis regulated by the transcription factors, Snail1 and Twist, was found to be reverted in vitro by PTER-ITC treatment. PTER-ITC blocked the activation of NF-κB/p65 and its concomitant nuclear translocation, resulting in the transcriptional repression of its target genes, Snail1 and Twist. PTER-ITC prevented the formation of IKK complex, central to NF-κB activation, by binding to the NEMO-binding domain (NBD) of IKK-β and inhibiting its interaction with NEMO (NF-κB essential modulator). According to our observations, PTER-ITC attenuated NF-κB activation selectively in cancerous cells. In conclusion, this study demonstrated that PTER-ITC is a potent anti-metastatic agent capable of targeting physiologically important pathways in a cancer-specific manner.

Immunoexpression of Epithelial Mesenchymal Transition Proteins E-Cadherin, β-Catenin, and N-Cadherin in Oral Squamous Cell Carcinoma

Aims Epithelial mesenchymal transition (EMT) is a crucial process for acquisition of malignant phenotype, aggressiveness, and metastatic capacity in neoplasms. It is characterized by loss of epithelial markers and gain of mesenchymal markers. Studies on EMT and its potential association with the histological grading are sparse in oral squamous cell carcinoma (OSCC). This study aims to evaluate the expression of EMT-associated proteins-E-cadherin, β-catenin, and N-cadherin-in different grades of OSCC. Methodology In all, 60 cases of OSCC further subdivided into 20 cases each of well-, moderately, and poorly differentiated OSCCs were stained immunohistochemically with E-cadherin, β-catenin, and N-cadherin antibodies. The differences in the expression were evaluated using χ² and Fisher exact tests, whereas Spearman's correlation was used to analyze the correlation between the markers. Results A reduced E-cadherin expression noted in 40% of the OSCCs was associated with reduced β-catenin expression in 66.6% of the cases and increase in the expression of mesenchymal N-cadherin seen in 80% of cases. This expression pattern demonstrated a significant association with histological grades. A membrane to cytoplasmic shift of E-cadherin (73.3%) and β-catenin (78.3%) increased with histological grade. A negative correlation was observed with the E-cadherin and N-cadherin localization, though it did not reach statistical significance. Conclusion OSCC tissues had high levels of EMT phenotype as compared with the normal oral mucosa. This phenotype was characterized by reduced E-cadherin and β-catenin expression and overexpression of N-cadherin. Aberrant localization of the studied proteins was a hallmark for depicting EMT.

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.

Expression of N-cadherin in salivary gland tumors

OBJECTIVE

To detect immunohistochemically the N-cadherin expression in different types of benign and malignant salivary gland tumors in an attempt to note any possible correlation to their development, stage and invasive properties.

MATERIALS AND METHODS

N-cadherin expression was examined in tissue specimens from 49 salivary gland tumors including: pleomorphic adenomas (4), Warthin's tumors (10), and myoepitheliomas (4) (benign tumors), as well as adenoid cystic carcinomas (14), mucoepidermoid carcinomas (4), polymorphous low-grade adenocarcinomas (6), and adenocarcinomas not otherwise specified (5) (malignant tumors). Twelve specimens of normal salivary glands were used as control. The perineural invasion and stage of malignant salivary gland tumors were evaluated. Immunohistochemical procedure was performed automatically using the Bond Polymer Refine Detection Kit.

RESULTS

N-cadherin expression was not found in normal salivary glands. In benign salivary gland tumors, N-cadherin along membranes of neoplastic cells as well as in centrocytes of lymphoid germinal centers was seen in 1 and 4 cases of Warthin's tumors, respectively. Varied degree of N-cadherin expression was found in 13 (45%) cases of malignant salivary gland tumors. N-cadherin expression was significantly correlated with perineural invasion (χ(2) = 11.7, p < 0.0001), but not with stage of malignant salivary gland tumors.

CONCLUSION

N-cadherin expression was observed in malignant salivary gland tumors and could be an indicator of potentially aggressive behavior. N-cadherin expression by tumor cells could be attributed to perineural invasion.

N-cadherin expression in malignant germ cell tumours of the testis

BACKGROUND

Testicular germ cell tumours (TGCTs) are the most common malignancy in young men aged 18-35 years. They are clinically and histologically subdivided into seminomas and non-seminomas. Cadherins are calcium-dependent transmembrane proteins of the group of adhesion proteins. They play a role in the stabilization of cell-cell contacts, the embryonic morphogenesis, in the maintenance of cell polarity and signal transduction. N-cadherin (CDH2), the neuronal cadherin, stimulates cell-cell contacts during migration and invasion of cells and is able to suppress tumour cell growth.

METHODS

Tumour tissues were acquired from 113 male patients and investigated by immunohistochemistry, as were the three TGCT cell lines NCCIT, NTERA-2 and Tcam2. A monoclonal antibody against N-cadherin was used.

RESULTS

Tumour-free testis and intratubular germ cell neoplasias (unclassified) (IGCNU) strongly expressed N-cadherin within the cytoplasm. In all seminomas investigated, N-cadherin expression displayed a membrane-bound location. In addition, the teratomas and yolk sac tumours investigated also differentially expressed N-cadherin. In contrast, no N-cadherin could be detected in any of the embryonal carcinomas and chorionic carcinomas examined. This expression pattern was also seen in the investigated mixed tumours consisting of seminomas, teratomas, and embryonal carcinoma.

CONCLUSIONS

N-cadherin expression can be used to differentiate embryonal carcinomas and chorionic carcinomas from other histological subtypes of TGCT.

P-cadherin expression in feline mammary tissues

The search for molecular markers in the feline mammary gland, namely, the adhesion molecules belonging to the cadherin family, is useful in the understanding of the development of mammary carcinomas in felines and humans. To study P-cadherin expression in the feline mammary gland, 61 samples of normal (n = 4), hyperplastic (n = 12), and neoplastic (n = 45) feline mammary tissues were examined. In both normal and hyperplastic mammary tissues as well as in benign tumours, P-cadherin immunolabelling was restricted to myoepithelial cells. In malignant tumours, however, there was an aberrant epithelial P-cadherin immunoexpression in 64.1% (n = 25) of cases, with a membranous and/or cytoplasmic pattern of distribution. A statistically significant relationship was seen between epithelial P-cadherin expression and malignant mammary lesions (P = 0.0001). In malignant mammary tumours, there was likewise a statistically significant relationship between aberrant P-cadherin immunoexpression and histological grade (P = 0.0132). Aberrant epithelial P-cadherin expression seems to be related to malignancy in the feline mammary gland. To confirm the results of this investigation, further studies with larger samples and follow-up studies are warranted.

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.

N-cadherin is differentially expressed in histological subtypes of papillary renal cell carcinoma

Background

Papillary renal cell carcinoma (RCC) represents a rare tumor, which is divided, based on histological criteria, into two subtypes. In contrast to type I papillary RCC type II papillary RCC shows a worse prognosis. So far, reliable immunohistochemical markers for the distinction of these subtypes are not available.

Methods

In the present study the expression of N(neural)-, E(epithelial)-, P(placental)-, und KSP(kidney specific)-cadherin was examined in 22 papillary RCC of histological type I and 18 papillary RCC of histological type II (n = 40).

Results

All papillary RCC type II displayed a membranous expression for N-cadherin, whereas type I did not show any membranous positivity for N-cadherin. E-cadherin exhibited a stronger, but not significant, membranous as well as cytoplasmic expression in type II than in type I papillary RCC. A diagnostic relevant expression of P- and KSP-cadherin could not be demonstrated in both tumor entities.

Conclusion

Thus N-cadherin represents the first immunhistochemical marker for a clear cut differentiation between papillary RCC type I and type II and could be a target for therapy and diagnostic in the future.

Virtual slides

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/2011556982761733

Clinical implications of N-cadherin expression in gastric cancer

Neo-expression of N-cadherin in cancer cells is regarded as a significant event in tumor progression via epithelial-mesenchymal transition (EMT). No reports have detailed the clinical impact of N-cadherin expression in gastric cancer. We retrospectively examined the co-expression of N-cadherin and E-cadherin in human gastric carcinoma and analyzed the clinicopathological significance of N-cadherin expression. One hundred and forty-six gastric cancer patients who received curative gastrectomy were enrolled. E-cadherin and N-cadherin immunoreactivity in cancer tissue was evaluated by the avidin-biotin-peroxidase complex technique. The correlation between N-cadherin and E-cadherin expression and clinicopathological parameters were analyzed. N-cadherin-positive and -negative expression were found in 31 and 115 patients, respectively. N-cadherin expression positively correlated with hematogenous recurrence (P < 0.01) and negatively correlated with patients' postoperative outcomes (P < 0.05). Moreover, only in the E-cadherin-preserved group was prognostic significance found according to N-cadherin expression (P < 0.01). We could not show a significant relationship between N-cadherin expression and EMT in gastric cancer. However, neo N-cadherin expression significantly affected patient's survival in gastric cancer. Therefore, we concluded that neo N-cadherin expression may be a useful prognostic marker independent of E-cadherin expression.

P-cadherin expression as a prognostic biomarker in a 3992 case tissue microarray series of breast cancer

P-cadherin is a calcium-dependent cell-cell adhesion glycoprotein. P-cadherin expression is restricted to the myoepithelial cells in normal breast tissue, and aberrant staining has also been described in invasive tumors. Several small studies have reported P-cadherin as a marker of poor outcome in breast cancer patients but its prognostic significance in relation to other variables has not been established in a large series of breast cancers. A tissue microarray was constructed from 3992 cases of invasive breast carcinoma, and P-cadherin expression was evaluated using immunohistochemistry. Median follow-up was 12.5 years. The immunohistochemistry-based definitions of cancer subtypes were luminal (ER+ or PR+/HER2-), luminal/HER2+ (ER+ or PR+/HER2+), HER2+ (ER-/PR-/HER2+), and basal (ER-/PR-/HER2-/CK5/6+ or EGFR+). Clinical covariate and biomarker associations were assessed using contingency tables, and Pearson's χ(2) or Fisher's exact test. Survival associations were assessed using Kaplan-Meier plots, logrank and Breslow tests, and Cox proportional hazards regression analysis. P-cadherin was expressed in 34.8% (1290/3710, 50% cut point) of cases. P-cadherin staining was strongly associated with HER2+ and basal carcinoma subtypes (P<0.0005). P-cadherin-positive patients showed significantly poorer short-term (0-10 years) overall survival, disease-specific survival, distant relapse-free interval, and locoregional relapse-free interval in univariable models (P<0.05). In multivariable Cox models containing standard clinical covariates and cancer subtypes, P-cadherin did not show independent prognostic value. P-cadherin expression was positively associated with histological grade, chemotherapy, Ki-67, EGFR, CK5/6, p53, YB-1, and HER2 expression (P<0.002), and negatively associated with age at diagnosis, ER, PR, and Bcl-2 expression (P<0.0005). This study shows the value of P-cadherin as a marker of poor prognosis. The large sample size of this series clarifies contradictory findings of many smaller studies. P-cadherin positivity is associated with high-grade tumor subtypes and well-established markers of poor prognosis, and may represent a promising antibody therapeutic target.

N-cadherin expression is correlated with metastasis of spindle cell carcinoma of head and neck region

Spindle cell carcinoma (SpCC) is a biphasic tumor composed of conventional squamous cell carcinoma and a malignant spindle cell component. SpCC expresses both epithelial and mesenchymal markers by immunohistochemical analysis. There is mounting evidence for sarcomatoid transformation from the epithelial component, supporting the theory that SpCC is a monoclonal neoplasm originating from a stem cell giving rise to both components. The loss of E-cadherin and the gain of N-cadherin expression are known as the "cadherin switching". Cadherin switching is a major hallmark of epithelial-mesenchymal transition (EMT). EMT is a crucial process in cancer progression providing cancer cells with the ability to escape from the primary focus, to invade stromal tissues, and to migrate to distant regions. Although E-cadherin down-regulation is well known in various cancers, there are a few studies on N-cadherin expression in cancer. Here, therefore, we investigated N-cadherin expression in the progression of head and neck SpCC. First, we examined cadherin switching in our established SpCC cell lines, SpCC-1 and SpCC-2. SpCC-1 and SpCC-2 cells were spindle in shape and showed cadherin switching. Moreover, we examined N-cadherin expression in 15 SpCC cases by immunohistochemistry. Although N-cadherin expression was not observed in non-neoplastic squamous epithelium, high expression of N-cadherin was observed in 10 of 15 SpCC cases. Interestingly, 6 of 7 SpCC cases with metastasis showed high expression of N-cadherin. In conclusion, our findings suggest that N-cadherin may play an important role in metastasis of SpCC in addition to the pathogenesis of SpCC of the head and neck.

Stromal fibroblasts from the interface zone of human breast carcinomas induce an epithelial-mesenchymal transition-like state in breast cancer cells in vitro

Fibroblasts were extracted from tissue in tumor burden zones, distal normal zones and interface zones between tumor and normal tissue of human breast carcinomas, and the corresponding fibroblasts were designated as cancer-associated fibroblasts (CAFs), normal zone fibroblasts (NFs) and interface zone fibroblasts (INFs). The crosstalk between three types of fibroblasts and breast cancer cells was evaluated using an in vitro direct co-culture model. We found that INFs grew faster and expressed higher levels of fibroblast activation protein than did NFs and CAFs. Compared with CAFs and NFs, INFs grown with breast cancer cells were significantly more effective in inducing an epithelial-mesenchymal transition (EMT) in cancer cells, as indicated by induction of vimentin and N-cadherin and downregulation of E-cadherin. This EMT process was also accompanied by activation of extracellular signal-regulated kinase (ERK) and modulation of membrane-type 1 matrix metalloproteinase (MT1-MMP) expression. Additionally, INFs promoted breast cell migration to a larger extent compared with NFs and CAFs. Taken together, these findings indicate that INFs isolated from the tumor interface zone exhibited more robust biological modulatory activity than did NFs and CAFs isolated from normal and tumor zones of the same tumor tissue, suggesting that the interface zone of the tumor represents a dynamic region vital to tumor progression.

Markers of epithelial-mesenchymal transition and epithelial differentiation in sarcomatoid carcinoma: utility in the differential diagnosis with sarcoma

The distinction between sarcomatoid carcinoma (SC) and bona fide sarcoma can be difficult using conventional immunohistochemical markers. Epithelial-mesenchymal transition (EMT) has been proposed as a histogenetic mechanism for the development of SC. Expression of selected markers of EMT (Twist and Slug) was compared with other markers of epithelial differentiation in SC and spindle cell sarcoma to determine the utility of these antigens in this differential diagnosis. Twenty-seven cases of SC (excluding those of gynecologic origin) were stained by immunohistochemistry for cytokeratins (AE1/AE3, 5D3, CK5/6, and 34betaE12), p63, claudin-1, claudin-7, epithelial cadherin, placental cadherin, epithelial cell adhesion molecule/epithelial-specific antigen, 14-3-3sigma, Twist, and Slug. A comparison group of 21 spindle or pleomorphic spindle cell sarcomas was also studied. Immunohistochemical stains were scored in a semiquantitative manner and subsequent exploratory analyses were performed using logistic regression and chi2 tests. Only cytokeratin AE1/AE3 specifically labeled SC in a statistically significant manner. Other epithelial-specific markers tested did not distinguish SC from sarcoma primarily owing to low sensitivity. However, when positive, immunostains such as CK5/6, membranous epithelial cadherin, and nuclear p63 may aid in the distinction of SC from sarcoma. EMT markers were expressed in most cases of both SC and sarcoma, and were not useful in making a differential diagnosis between these neoplasms.

Cadherin switching

The cadherin molecules at adherens junctions have multiple isoforms. Cadherin isoform switching (cadherin switching) occurs during normal developmental processes to allow cell types to segregate from one another. Tumor cells often recapitulate this activity and the result is an aggressive tumor cell that gains the ability to leave the site of the tumor and metastasize. At present, we understand some of the mechanisms that promote cadherin switching and some of the pathways downstream of this process that influence cell behavior. Specific cadherin family members influence growth-factor-receptor signaling and Rho GTPases to promote cell motility and invasion. In addition, p120-catenin probably plays multiple roles in cadherin switching, regulating Rho GTPases and stabilizing cadherins.

P-cadherin expression in breast cancer: a review

P-cadherin is frequently over-expressed in high-grade invasive breast carcinomas and has been reported to be an enhancer of migration and invasion of breast cancer cells, being correlated with tumour aggressiveness. In addition, expression of P-cadherin is well established as an indicator of poor prognosis in human breast cancer, which has stimulated our interest in studying its role in this setting. This review describes the most important findings on P-cadherin expression and function in normal mammary tissue and breast cancer cells, emphasizing that further research is required to elucidate the role played by this protein in human mammary tumours.

Laminin 5 expression in metaplastic breast carcinomas

Metaplastic carcinoma of the breast shows squamous, sarcomatous, or chondromatous differentiation and has a poor prognosis. Laminin 5 is a heterotrimer of alpha3, beta3, and gamma(2) [corrected] chains and induces aggressive properties in cancer cells including motility, invasion, and epithelial to mesenchymal transition. Twenty-five cases included 7 squamous, 4 sarcomatous, 8 chondroid, 1 fibromatosislike metaplastic carcinomas, and 5 cases with 2 metaplastic components. Tumors were stained with laminin 5-specific beta3 and gamma(2) [corrected] chain, p63, and cytokeratin 5/6 (CK 5/6) antibodies. All 4 antibodies stained normal myoepithelium. Both laminin 5 antibodies stained 24/25 (96%) of the tumors, with an identical distribution of the 2 chains in 87.5% of the positively staining cases. In contrast, p63 and CK 5/6 stained 68% and 64% of the tumors, respectively. By comparison, only 16% of high-grade carcinoma controls stained for laminin 5. Similar to the metaplastic carcinomas, all 12 triple negative tumors, those negative for estrogen receptor, progesterone receptor, and Her2/neu, expressed laminin 5. None of 4 breast sarcomas stained for either of the laminin 5 chains or CK 5/6, but 1 (25%) stained for p63. Laminin 5 expression in metaplastic and other basal-like carcinomas is of interest for several reasons. First, these data provide additional evidence of the myoepithelial and basal-like phenotype of these carcinomas. Second, these are the only breast carcinoma subtypes to demonstrate laminin 5 staining in a large proportion of cases. Third, expression of laminin 5 in metaplastic carcinomas may suggest a mechanism for their increased aggressiveness and epithelial to mesenchymal transition phenotype. Finally, compared with other myoepithelial markers, laminin 5 is more sensitive than those previously published. Thus laminin 5 may be helpful for making the diagnosis of metaplastic carcinomas in biopsies, allowing the potential for aggressive early treatment. Further study of other basal-like tumors for laminin 5 expression is warranted to determine the usefulness of laminin 5 in their diagnosis.

Tissue microarrays for testing basal biomarkers in familial breast cancer cases

CONTEXT AND OBJECTIVE

The proteins p63, p-cadherin and CK5 are consistently expressed by the basal and myoepithelial cells of the breast, although their expression in sporadic and familial breast cancer cases has yet to be fully defined. The aim here was to study the basal immunoprofile of a breast cancer case series using tissue microarray technology.

DESIGN AND SETTING

This was a cross-sectional study at Universidade Estadual de Campinas, Brazil, and the Institute of Pathology and Molecular Immunology, Porto, Portugal.

METHODS

Immunohistochemistry using the antibodies p63, CK5 and p-cadherin, and also estrogen receptor (ER) and Human Epidermal Receptor Growth Factor 2 (HER2), was per-formed on 168 samples from a breast cancer case series. The criteria for identifying women at high risk were based on those of the Breast Cancer Linkage Consortium.

RESULTS

Familial tumors were more frequently positive for the p-cadherin (p = 0.0004), p63 (p < 0.0001) and CK5 (p < 0.0001) than was sporadic cancer. Moreover, familial tumors had coexpression of the basal biomarkers CK5+/ p63+, grouped two by two (OR = 34.34), while absence of coexpression (OR = 0.13) was associated with the sporadic cancer phenotype.

CONCLUSION

Familial breast cancer was found to be associated with basal biomarkers, using tissue microarray technology. Therefore, characterization of the familial breast cancer phenotype will improve the understanding of breast carcinogenesis.

Molecular Targets of Growth, Differentiation, Tissue Integrity, and Ectopic Cell Death in Cancer Cells

Cancer cells continue to grow, lose their differentiation, and are found beyond their tissue boundaries, where they survive. These phenomena lead to cancer invasion and metastasis and are responsible for the outcome of the disease in cancer patients. Different factors determine where and when the cells will metastasize. The surrounding host cells, such as fibroblasts, macrophages, leukocytes, et cetera, and the extracellular matrix play an important role in the creation of the microenvironment for the cancer cells to invade. Blood and lymph vessels are not only the transporters of nutrients and metabolites for the primary tumor, these vessels also transport cancer cells to distant sites, where they metastasize. Angiogenesis and host cells are targets in cancer treatment. To monitor therapy or to predict cancer relapses, circulating tumor markers are used that reflect the molecular cross-talk between cancer and stromal cells.

Placental Cadherin and the Basal Epithelial Phenotype of BRCA1-Related Breast Cancer

PURPOSE

BRCA1-related breast cancer frequently has a basal epithelial phenotype, and P-cadherin is a basal marker. We undertook a detailed evaluation of the relationship among P-cadherin, prognostic markers in breast cancer, and outcome.

EXPERIMENTAL DESIGN

This study was restricted to 292 cases of first primary invasive breast cancer diagnosed in Ashkenazi Jewish women between 1980 and 1995. All available blocks were stained for P-cadherin, and 261 were included in the final statistical analyses, including 27 germ line BRCA1 mutation carriers and 8 BRCA2 mutation carriers. Descriptive analyses were done followed by survival analyses and a Poisson regression analysis.

RESULTS

P-cadherin was present in 80 of the 261 breast cancers (31%) and was more frequently present in tumors that have a basal epithelial phenotype [i.e., high-grade, estrogen receptor- and KIP1 (p27(Kip1))-negative tumors, with expression of cytokeratin 5/6, cyclin E, TP53, and presence of BRCA1 mutations and vascular nests (all P < 0.001)]. In a univariate survival model, expression of P-cadherin was associated with a relative risk (RR) of death from breast cancer at a 10-year follow-up of 2.9 (95% confidence interval, 1.8-4.7; P < 0.0001) and was a predictor of poor univariate survival in both lymph node-negative and -positive breast cancers. In a multivariate analysis, the effect of P-cadherin levels was not independent of other basal-related markers. Multivariable interaction modeling showed that P-cadherin positivity was highly predictive of a poor prognosis in small, node-negative breast cancers (RR, 7.1; P = 0.006).

CONCLUSIONS

P-cadherin is a marker for basal-like breast cancers and is strongly associated with the presence of a BRCA1 mutation. It is an adverse prognostic factor, particularly in small, node-negative breast cancers.

Lymphoepithelioma-like carcinoma of the breast: Report of a case mimicking lymphoma

Only 10 cases of lymphoepithelioma-like carcinoma of the breast have been reported in the literature. This report adds one more case to the published literature. A 62-year-old woman presented with a mass in her left breast on physical examination. The mammographic images showed a 3.0 cm, poorly defined mass in the upper outer quadrant. A biopsy was recommended. The gross specimen consisted of a 5 cm portion of breast parenchyma with no discrete tumor. On microscopic examination, the tumor was composed of sheets of epithelioid cells arranged as single cells or in cords partially obscured by a dense lymphocytic infiltrate. The epitheliod cells extensively expressed cytokeratin stain, but did not express E-cadherin. The lymphoid cells expressed L26 stain in the germinal centers, and CD3 stain in the T lymphocytes surrounding the germinal centers and in between tumor cells. In situ hybridization showed no evidence of Epstein-Barr virus infection in the tumor cells. An overall review of 11 cases shows that the disease is usually seen in older patients. In situ and invasive lobular component was reported in 36% of the cases. Eight of 11 were negative for E-cadherin, 36% were estrogen receptor-positive, 18% were progesterone receptor-positive, and all of them were HER2/neu negative. None of the reported cases have been associated with Epstein-Barr virus infection. Only two of the cases showed lymph node metastasis, and long-term follow-up in one of them showed good prognosis. In summary, lymphoepithelioma-like carcinoma of the breast is a tumor with a good prognosis that should be considered as a possible diagnosis in breast tumors with an intense lymphocytic infiltrate.

P-cadherin expression in canine mammary tissues

P-cadherin is a classical cadherin expressed by myoepithelial cells in mammary tissue. Its expression in human breast cancer has been associated with aggressive tumour behaviour. To analyse the possible role of P-cadherin in canine mammary carcinogenesis, its expression was examined immunohistochemically in 82 samples of normal (n=2), hyperplastic (n=11) and neoplastic (n=69) canine mammary tissues. In normal and hyperplastic canine mammary glands, P-cadherin was restricted to myoepithelial cells, usually at sites of cell-to-cell contact. In tumour tissues, however, P-cadherin expression was observed in both epithelial and myoepithelial cells, with a cytoplasmic pattern of cellular distribution. Aberrant epithelial P-cadherin immunolabelling was found in 19/44 (43%) benign tumours and in 16/25 (64%) malignant tumours (P<0.001). In malignant tumours, a significant correlation between P-cadherin expression intensity and histological type was observed (P<0.05).

Expression of P-cadherin, but not E-cadherin or N-cadherin, relates to pathological and functional differentiation of breast carcinomas

AIMS

To compare the expression of the cell adhesion molecules P-cadherin, N-cadherin, and E-cadherin in invasive and in situ breast carcinomas relative to clinicopathological features (size, node status, type, grade, and receptors) to determine whether expression patterns relate to specific tumour characteristics.

METHODS

Using immunohistochemistry, 110 invasive and in situ breast carcinomas were examined for the presence, extent, and localisation of all three cadherins. Findings were related to tumour size, type, grade, node status, oestrogen (ER), progesterone, and epidermal growth factor receptor (EGFR) expression for invasive carcinomas and to grade and receptors for in situ carcinomas.

RESULTS

P-cadherin was detected in 40% of invasive carcinomas, N-cadherin in 30%, and E-cadherin in 81%. For invasive carcinomas, the presence of P-cadherin significantly correlated with high grade, lack of ER and presence of EGFR, but not tumour size or node status. Carcinomas containing P-cadherin could be put into three categories dependent upon receptor and E-cadherin profile. There were no correlations between E/N-cadherin and size, grade, node status, or receptors. Three of 16 infiltrating lobular carcinomas expressed cytoplasmic but none membranous E-cadherin, and P-cadherin and N-cadherin were present in four carcinomas of this type. E-cadherin was found in all ductal carcinomas in situ, P-cadherin in a proportion of high grade tumours, and N-cadherin in a mixture of grades.

CONCLUSION

P-cadherin but not E/N-cadherin expression in breast carcinomas shows a strong correlation with higher grade (poorer differentiation), lack of ERs, and presence of EGFR, and its expression may aid in the further subdivision of high grade carcinomas.

Benign and malignant spindle cell lesions of the breast

Spindle cell lesions of the breast constitute a wide spectrum of benign and malignant proliferations. Myofibroblasts, normal cellular constituents of the mammary intra- and interlobular stroma, compose many of these lesions, which include reactive proliferations and benign or locally aggressive neoplasms. Because of its morphology, low-grade metaplastic spindle cell carcinoma, "fibromatosis-like" is also considered together with spindle cell lesions of the breast. Although certain of the lesions do not occur commonly, they represent diagnostic challenges. This review outlines the morphology of certain spindle cell lesions of the breast including pseudoangiomatous stromal hyperplasia, reactive spindle cell nodule, nodular fasciitis, myofibroblastoma, primary mammary fibromatosis, and low-grade metaplastic spindle cell carcinoma, "fibromatosis-like." The differential diagnosis and diagnostic work-up of these lesions is discussed, and their clinical treatment and prognosis briefly summarized.

The epithelial cell adhesion molecule (Ep-CAM) as a morphoregulatory molecule is a tool in surgical pathology

Cell adhesion receptors (CAMs) are actively involved in regulating various cell processes, including growth, differentiation, and cell death. Therefore, CAMs represent a large group of morphoregulating molecules, mediating cross-talk between cells and of cells with their environment. From this perspective, CAMs do contribute to cells and tissue organization, and in diseased tissue, to the disease development and biological characteristics. Therefore, observed changes in expression patterns of adhesion molecules may contribute to establish a diagnosis. A distinct shift in expression patterns in neoplastic epithelium has been described, for example for cadherins, integrins, and CD44. A relatively novel cell CAM, Ep-CAM, was first reported to be a pan-carcinoma antigen, although it is rather a marker of epithelial lineage. Several antibodies directed to Ep-CAM have been generated, and many epithelial tissues and their neoplastic appendages have been studied. This article outlines the results of these studies. Based on the results of these studies, we conclude that Ep-CAM immunohistochemistry can be a useful tool in the diagnosis of disturbed epithelial tissues.

Aberrant P-cadherin expression: is it associated with estrogen-independent growth in breast cancer?

Breast carcinomas represent a heterogeneous group of tumors, with a diverse biologic behavior, outcome, and response to therapy. Recent studies have demonstrated that alterations in the expression of adhesion molecules in cancer cells are related to aggressiveness and poor prognosis. The aim of our study was to investigate the expression of P-cadherin in breast carcinomas and correlate it with estrogen receptor (ER) status. We selected 73 ductal carcinomas in situ (DCIS) and 149 invasive carcinomas of the breast, and assessed the expression of P-cadherin as well as other biologic markers. P-cadherin expression showed a strong inverse correlation with ER expression in both types of breast carcinoma (in situ and invasive). P-cadherin-positive and ER-negative tumors were related to a higher histologic grade, a high proliferation rate, and expression of c-erbB-2. We demonstrated that P-cadherin identifies a subgroup of breast carcinomas that lacks ER expression, and correlates with higher proliferation rates and other predictors of aggressive behavior. We believe that these tumors represent an advanced step in cancer progression, and our data support the hypothesis that an estrogen-independent pathway regulates P-cadherin expression.

Novel and classic myoepithelial/stem cell markers in metaplastic carcinomas of the breast

Metaplastic carcinomas of the breast (MCBs) are unusual neoplasms characterized by an admixture of glandular epithelial components, which frequently exhibit features of squamous differentiation, and mesenchymal malignant components. Regardless of the presence of myoepithelial features in MCB, no consensus concerning their putative histogenesis has yet been achieved. Recently, novel putative myoepithelial markers have been developed, including p63, maspin, and P-cadherin. We assessed the expression of these myoepithelial markers in MCBs and compared their expression with classic myoepithelial markers. Immunohistochemistry using the streptavidin-biotin-peroxidase complex technique with antibodies raised against p63, maspin, P-cadherin, actin (clones CGA7, 1A4 and HHF35), cytokeratin 14 (Ck14), and vimentin was performed on 16 MCBs (7 matrix-producing MCBs, 6 adenosquamous MCBs, and 3 MCBs with heterologous elements). In healthy breast lobules and ducts adjacent to the tumors, myoepithelial cells showed distinctive and consistent immunoreactivity for p63, maspin, P-cadherin, actin, S-100 protein, and Ck14. Matrix-producing MCBs were positive for maspin in all cases, for p63 in 4 of 7 cases, and for P-cadherin in 4 of 7 cases. Adenosquamous MCB showed immunoreactivity for p63, maspin, and P-cadherin in 5 of 6 cases. All novel myoepithelial markers and Ck14 decorated squamous cell islands. MCBs with heterologous elements were positive for p63 in 1 case, for maspin in all 3 cases, and for P-cadherin in 2 cases. All cases showed at least one of the novel myoepithelial markers. Eleven of 16 cases were positive for actin. Eleven of 14 cases reacted with Ck14, and all cases that stained for S-100 protein (9 of 9) and vimentin (13 of 13) were also positive. Based on our findings, the balance of probabilities favors that MCBs may have a basal or myoepithelial cell histogenesis and differentiation.

E-cadherin promoter methylation can regulate its expression in invasive ductal breast cancer tissue in Chinese woman

Promoter methylation is an important mechanism of regulating E-cadherin expression. Methylation-specific PCR (MSP) assay was done to evaluate the promoter methylation status of E-cadherin gene in primary tumor samples from 23 cases of Chinese women with invasive ductal breast cancers. Western blotting assay was employed for E-cadherin and beta-actin expressions. Positive MSP results occurred in 26.1% (6/23) of primary tumor samples and none of four normal skin samples. These molecular events tended to occur in breast cancers associated with poor prognosis. Whereas the mean ratio of CDH1/beta-actin for six MSP-positive cases was 0.0290 +/- 0.0355, the mean ratio for 17 MSP-negative cases was 0.4726 +/- 0.5049 (P = 0.046). In conclusion, aberrant E-cadherin methylation preferentially occurs in invasive ductal breast cancer associated with poor prognosis and is one of the mechanisms of E-cadherin expression silence in breast cancers from Chinese women.

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.

Epithelial-type and neural-type cadherin expression in malignant noncarcinomatous neoplasms with epithelioid features that involve the soft tissues

CONTEXT

Transmembrane adhesion molecules, epithelial-type cadherin (ECAD) and neural-type cadherin (NCAD), help in regulating transformations between epithelial and mesenchymal cells in the developing embryo and in maintaining the epithelioid phenotype. Consequently, the presence of epithelioid cells in certain malignant noncarcinomatous neoplasms raises speculation that the expression of ECAD and NCAD in these neoplasms may have diagnostic significance.

OBJECTIVE

To investigate the utility of ECAD and NCAD immunoexpression in distinguishing malignant (noncarcinomatous) neoplasms with epithelioid features that involve the soft tissues.

DESIGN

Membranous immunoreactivity of anti-ECAD and anti-NCAD was evaluated on archived cases selected from the files of the Armed Forces Institute of Pathology.

RESULTS

Epithelial-type cadherin was found in biphasic synovial sarcoma (35 of 35 cases), malignant melanoma (13/21), monophasic fibrous synovial sarcoma (13/26), clear cell sarcoma (4/9), poorly differentiated synovial sarcoma (3/13), diffuse mesothelioma (4/20), malignant epithelioid peripheral nerve sheath tumor (1/6), and epithelioid sarcoma (5/62). Neural-type cadherin was observed in chordoma (11/11), biphasic synovial sarcoma (30/35), diffuse mesothelioma (14/20), malignant melanoma (14/25), epithelioid sarcoma (24/63), epithelioid angiosarcoma (1/4), poorly differentiated synovial sarcoma (2/13), clear cell sarcoma (1/10), and monophasic fibrous synovial sarcoma (1/26). Eighteen cases of primary cutaneous squamous cell carcinomas all tested positive for ECAD, whereas NCAD was focally observed in 5 cases. No expression of either molecule was observed in cases of epithelioid hemangioendothelioma (n = 9), alveolar soft part sarcoma (n = 8), and extraskeletal myxoid chondrosarcoma (n = 7).

CONCLUSIONS

Epithelial-type and neural-type cadherins are found in a variety of noncarcinomatous neoplasms with epithelioid features that involve the soft tissues and can be utilized, in association with other immunomarkers, in distinguishing chordoma (100% NCAD) from extraskeletal myxoid chondrosarcoma and conventional chondrosarcoma of bone (0% NCAD), squamous cell carcinoma (100% ECAD) from epithelioid sarcoma (8% ECAD), and biphasic synovial sarcoma (100% ECAD) from diffuse mesothelioma (20% ECAD).

The prognostic significance of P-cadherin in infiltrating ductal breast carcinoma

We have immunohistochemically investigated P-cadherin (P-CD) expression in a series of 210 infiltrating ductal carcinomas (IDC) in an attempt to assess the biological and prognostic relevance of P-CD in patients harboring IDCs. Although only 74/210 (35%) of IDCs expressed P-CD in >5% of tumor cells (P-CD-positive carcinomas), categorical analyses revealed that P-CD-positive IDCs were larger (26 +/- 21 cm versus 22 +/- 11 cm, P =.0568), of higher histological grade (P =.0001), and had more lymph node metastases (P =.0327) than P-CD-negative breast carcinomas. In addition, P-CD-positive tumors were negative for estrogen (P =.0001) and progesterone receptors (P =.0001) and showed reduced E-cadherin expression (P =.0276) more frequently than P-CD-negative tumors. Univariate analysis carried out in 171 patients demonstrated that P-CD expression was also an indicator of poor prognosis (chi(2) = 8.292, P =.004), extent of lymph node metastasis (chi(2) = 20.854, P =.0000), histological grade (chi(2) = 12.908, P =.0016), and negative progesterone receptors (chi(2) = 4.116, P =.042). However, only histological grade and nodal metastases emerged as independent prognostic markers in the multivariate analysis. These results suggest that although P-CD expression may be involved in the progression of IDCs, its value as an independent prognostic factor remains to be established.

Solid low-grade in situ carcinoma of the breast: role of associated lesions and E-cadherin in differential diagnosis

Low-grade solid in situ carcinomas of the breast are difficult to classify. The authors investigated 12 cases of in situ carcinomas with equivocal features and correlated their histologic attributes with those of the associated invasive carcinomas as well as with E-cadherin expression in both in situ and invasive disease. E-cadherin-positive in situ lesions were invariably associated with invasive carcinomas of the ductal type. In situ carcinomas that were E-cadherin negative were associated with invasive carcinomas of the lobular type in five of six cases. In all cases, the invasive carcinomas showed the same pattern of E-cadherin reactivity as the in situ lesions. Sharply defined cellular membranes, necrosis, and occasional microacini were seen in both E-cadherin-positive and negative in situ carcinomas, whereas intracytoplasmic lumina and a noncohesive appearance were seen only in E-cadherin-negative lesions.

Cadherin expression in glandular tumors of the cervix

BACKGROUND

The cadherins are homotypic adhesion proteins that are important in cell sorting during organogenesis. Classic cadherins include several different types that show tissue specific expression. Specific tissue expression of cadherins often is preserved in neoplastic transformation, and cadherin phenotype can be used to differentiate morphologically similar but histogenetically distinct tumors.

METHODS

The authors examined by using immunohistochemistry in paraffin sections the expression of E- (epithelial) and P- (placental) cadherin in 39 patients with glandular tumors of the cervix, including invasive adenocarcinoma, villoglandular adenocarcinoma, adenocarcinoma in situ (AIS), and adenoma malignum.

RESULTS

In all cases, E-cadherin was expressed in both normal and malignant glands without appreciable differences. P-cadherin, normally confined to basal epithelial cells and not observed in benign glands, was aberrantly expressed in neoplastic glands in 27 cases, including 96%(23 of 24 cases) of invasive cancers, 40% (2 of 5) of villoglandular carcinomas, 25% (2 of 8) of AIS, and 0% (0 of 2) of adenoma malignum.

CONCLUSIONS

The authors' results show that E-cadherin is uniformly expressed in glandular tumors of the cervix with no evidence of decreased expression in these tumors. In addition, P-cadherin is aberrantly expressed in most adenocarcinomas and appears to be preferentially expressed in invasive rather than in situ lesions. Thus, aberrant expression of P-cadherin may be a useful marker of invasive or aggressive clinical behavior in glandular lesions of the cervix.

Nuclear localization of E-cadherin expression in Merkel cell carcinoma

CONTEXT

Cadherins are cell-cell adhesion proteins that act as tumor suppressor genes and have a critical role in cell sorting and tissue formation during organogenesis. The pattern of cadherin expression constitutes a useful diagnostic and prognostic tool in the evaluation of tumors and for determining the histogenesis of tumor cells. We have previously characterized the cell types of several tumors based on the expression of individual cadherins.

OBJECTIVE

To investigate the expression of cadherins in Merkel cell carcinomas.

DESIGN

Paraffin immunohistochemical analysis of the 3 best-studied cadherins was performed on 35 cases of Merkel cell carcinoma.

RESULTS

E-cadherin was expressed in 34 (97%) of 35 Merkel cell carcinomas examined, N-cadherin was expressed in 22 (63%) of 35 cases, and P-cadherin was expressed in 15 (43%) of 35 cases. This frequency of cadherin expression was similar to a group of small cell and neuroendocrine tumors from other primary sites. Interestingly, the localization of E-cadherin expression was unique in Merkel cell carcinomas compared with other primary neuroendocrine tumors. Merkel cell carcinomas showed marked preference for nuclear versus membrane localization, whereas small cell tumors from other sites showed fewer cases of nuclear E-cadherin expression. The nuclear localization of E-cadherin did not correlate with cadherin-associated protein beta-catenin nuclear expression.

CONCLUSIONS

Our findings show that E-cadherin is the most frequently expressed cadherin in Merkel cell carcinoma, followed in frequency by N-cadherin then P-cadherin. The pattern of nuclear E-cadherin expression is more frequent for Merkel cell carcinoma than small cell tumors of other primary sites. These observations suggest that E-cadherin expression and function are altered in Merkel cell carcinoma, and this finding has potential use in the differential diagnosis of these tumors.