The role of the cell-cell adhesion molecule E-cadherin in large bowel tumour cell invasion and metastasis

Role of thrombospondin-1 expression in colorectal liver metastasis and its molecular mechanism

BACKGROUND

Thrombospondin-1 (THBS-1), a glycoprotein, is an endogenous inhibitor of angiogenesis and tumor growth. In this study, we investigated the clinical role and mechanism of THBS-1 expression in colorectal liver metastases, focusing on the relationships between its expression and tumor growth, epithelial-mesenchymal transition (EMT), and expression of other relevant molecules.

METHODS

Ninety-four patients who initially underwent curative hepatic resection were enrolled in this study and correlations between expression of THBS-1 (THBS-1 high [n = 35] and THBS-1 low [n = 59]) and tumor growth, Ki-67 labeling index (Ki-67 LI), expression of other relevant molecules, and microvessel density (MVD) investigated.

RESULTS

THBS-1 low expression correlated with more advanced grade of liver and lymph node metastases and significantly worse overall survival than strong THBS-1 expression (3-year survival: 96.7% vs. 65.4%, P < 0.01). Multivariate analysis identified THBS-1 low expression as an independent prognostic factor (HR 2.82, 95% CI 1.21-7.71, P = 0.01). THBS-1 low expression correlated positively with high Ki-67 LI (P < 0.05) and inversely with E-cadherin (P < 0.05) and hypoxia inducible factor-1α (HIF-1α) expression (P < 0.05); THBS-1 expression and MVD were not significantly correlated.

CONCLUSIONS

Low THBS-1 expression may be an independent poor prognostic factor that affects tumor growth and EMT acquisition. Additionally, THBS-1 may be regulated by the HIF-1 pathway.

Intraperitoneal Immunization with Cry1Ac Protoxin from Bacillus thuringiensis Provokes Upregulation of Fc-Gamma-II/and Fc-Gamma-III Receptors Associated with IgG in the Intestinal Epithelium of Mice

In humans, intestinal epithelial FcRn is expressed throughout life and mediates the bidirectional transport of IgG, but in mice, it is markedly expressed in neonatal intestine. In adults, its expression is only faintly upregulated after intestinal IgG induction such as that elicited by i.p. immunization with Cry1Ac protoxin (pCry1Ac) Bacillus thuringiensis. This led us to suggest that additional Fcγ receptors (Fcγ-R) may be participating in epithelial IgG uptake. So, first we determined whether CD16/32 [an epitope shared by Fcγ-RII (CD32) and Fcγ-RIII (CD16)] was expressed in the intestinal epithelia of mice. Using confocal microscopy and flow cytometry, we detected co-localization of IgG and CD16/32 in epithelial cells, whose frequency was increased by immunization with pCry1Ac. Western blot and cross-immunoprecipitation results with anti-CD16/32 and IgG antibodies in epithelial cell extracts suggested that epithelial cells bear both Fcγ-RII and Fcγ-RIII and contained IgG associated with Fcγ-RII/RIII. Using anti-CD32 and anti-CD16 antibodies, we confirmed by Western blot, confocal microscopy and flow cytometry that both Fcγ-RII and Fcγ-RIII were expressed and suggested that upregulation occurred upon immunization in intestinal epithelia. Finally, we examined the in vitro effect of anti-CD16/32, anti-CD16 and anti-CD32 antibodies on IgG uptake and transport by intestinal epithelial cells and found that it was partially reduced. Although further studies are still required, our results suggest that Fcγ-RII and Fcγ-RIII might participate in the uptake and/or transport of IgG through the intestinal epithelia of adult mice.

Micropapillary pattern and poorly differentiated clusters represent the same biological phenomenon in colorectal cancer: a proposal for a change in terminology

OBJECTIVES

Colorectal carcinomas (CRCs) with a micropapillary pattern and those showing high counts of poorly differentiated clusters (PDCs) are characterized by a higher probability to develop nodal metastases and have a worse prognosis. In light of the morphologic similarity to the micropapillary component, we aimed to verify whether PDCs also display an inverted secretory pattern.

METHODS

The immunohistochemical expression of MUC1 and E-cadherin was assessed in a cohort of CRCs with PDCs and compared with that observed in CRCs without PDCs.

RESULTS

PDCs in our cases always displayed an inverted MUC1 pattern. In addition, we found abnormal (lost or cytoplasmic) expression of E-cadherin in PDCs.

CONCLUSIONS

The altered expression of MUC1 and E-cadherin may account for the aggressive behavior and higher metastatic potential of CRCs with high PDC counts and indicate an epithelial-mesenchymal transition. Our findings suggest that regardless of the morphologic aspect, PDCs and the micropapillary component may reflect the same biological phenomenon in CRCs. Thus, we wonder whether the micropapillary areas should be considered a variant of CRCs or more objectively counted as PDCs to predict prognosis. We also believe that the term PDC better describes the biological phenomena underlying this peculiar morphologic aspect in comparison with the misnomer micropapillary.

Study of β-catenin, E-cadherin and vimentin in oral squamous cell carcinoma with and without lymph node metastases

Abstract

Virtual slides

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/6506095201182002.

Genome-wide activities of RNA binding proteins that regulate cellular changes in the epithelial to mesenchymal transition (EMT)

The epithelial to mesenchymal transition (EMT) and reverse mesenchymal to epithelial transition (MET) are developmentally conserved processes that are essential for patterning of developing embryos and organs. The EMT/MET are further utilized in wound healing, but they can also be hijacked by cancer cells to promote tumor progression and metastasis. The molecular pathways governing these processes have historically focused on the transcriptional regulation and networks that control them. Indeed, global profiling of transcriptional changes has provided a wealth of information into how these networks are regulated, the downstream targets, and functional consequence of alterations to the global transcriptome. However, recent evidence has revealed that the posttranscriptional landscape of the cell is also dramatically altered during the EMT/MET and contributes to changes in cell behavior and phenotypes. While studies of this aspect of EMT biology are still in their infancy, recent progress has been achieved by the identification of several RNA binding proteins (RBPs) that regulate splicing, polyadenylation, mRNA stability, and translational control during EMT. This chapter focuses on the global impact of RBPs that regulate mRNA maturation as well as outlines the functional impact of several key posttranscriptional changes during the EMT. The growing evidence of RBP involvement in the cellular transformation during EMT underscores that a coordinated regulation of both transcriptional and posttranscriptional changes is essential for EMT. Furthermore, new discoveries into these events will paint a more detailed picture of the transcriptome during the EMT/MET and provide novel molecular targets for treatment of human diseases.

Prognostic significance of transforming growth factor beta (TGF-β) signaling axis molecules and E-cadherin in colorectal cancer

The transforming growth factor beta (TGF-β) signaling pathway has been considered both a tumor suppressor and a cancer promoter. Additionally, downregulation of cell adhesion molecules such as E-cadherin plays an important role in the metastatic potential of colorectal cancer (CRC). The aim of the present study was to evaluate TGF-β, TGF-β type I receptor (TGF-βR1), TGF-β type II receptor (TGF-βR2), Smad4, pSmad2/3, and E-cadherin expression in colorectal carcinoma and to correlate the obtained data with other standard prognostic parameters, such as disease stage, metastases, and patient survival. TGF-β, TGF-βR1, TGF-βR2, Smad4, pSmad2/3, and E-cadherin expression was evaluated immunohistochemically in 195 unrelated CRC specimens and the results subjected to various statistical analyses. TGF-β was expressed in 71.28%, TGF-βR1 in 61.0%, TGF-βR2 in 54.4%, Smad4 in 61.5%, pSmad2/3 in 71.3%, and E-cadherin in 50.26% of the colorectal carcinoma samples tested. The correlation of immunoexpression with the clinicopathological parameters of CRC revealed that the high expression of TGF-β and low expression of TGF-βR1, TGF-βR2, Smad4, pSmad2/3, and E-cadherin were correlated with tumor-node-metastasis (TNM) stage of disease. High TGF-β expression and low TGF-βR1, TGF-βR2, Smad4, and pSmad2/3 expression were also correlated with lymph node metastasis. The Kaplan-Meier survival curves demonstrated a clear association of cancer-specific overall survival with high TGF-β, as well as low TGF-βR1, TGF-βR2, Smad4, pSmad2/3, and E-cadherin expression. Our results suggest that TGF-β, TGF-βR1, TGF-βR2, Smad4, pSmad2/3, and E-cadherin are closely related to TNM stage of CRC. Moreover, TGF-β, TGF-βR2, Smad4, pSmad2/3, and E-cadherin emerge as valuable independent biomarkers of prognosis in CRC patients.

E-cadherin expression in plasmacytoid, signet ring cell and micropapillary variants of urothelial carcinoma: comparison with usual-type high-grade urothelial carcinoma

Loss of E-cadherin expression has been linked to the invasive phenotypes of a variety of neoplasms, including lobular breast cancer. The expression of E-cadherin in variants of urothelial carcinoma relative to usual-type urothelial carcinoma, maximum depth of invasion and angiolymphatic invasion has not been well characterized. A total of eight cases of micropapillary urothelial carcinoma, four cases of plasmacytoid urothelial carcinoma, two cases of urothelial carcinoma with signet ring cell differentiation and two cases of urothelial carcinoma with mixed plasmacytoid and signet ring cell differentiation, all obtained from cystectomy/cystoprostatectomy cases, were identified. In all nine cases of usual-type invasive and noninvasive high-grade urothelial carcinoma were also included in the study. Immunohistochemical staining of E-cadherin was performed in all cases. Pathological parameters including depth of invasion and presence of angiolymphatic invasion were documented. Maximum depth of invasion: In micropapillary urothelial carcinoma, extravesical extension was seen in three of eight cases; muscularis propria invasion in four of eight cases; and lamina propria invasion in one of eight cases. In plasmacytoid urothelial carcinoma, extravesical extension was observed in two of four cases, and muscularis propria invasion and lamina propria invasion in one of four cases each. In urothelial carcinoma with signet ring cell differentiation, extravesical extension and muscularis propria invasion was seen in one of two cases each. In urothelial carcinoma with mixed plasmacytoid and signet ring cell differentiation, muscularis propria invasion and lamina propria invasion was observed in one of two cases each. In usual-type high-grade urothelial carcinoma, extravesical extension was seen in six of nine cases and noninvasive in three of nine cases. In angiolymphatic invasion, micropapillary urothelial carcinoma was observed in eight of eight cases; plasmacytoid urothelial carcinoma in two of four cases; urothelial carcinoma with signet ring cell differentiation in one of two cases; and urothelial carcinoma with mixed plasmacytoid and signet ring cell differentiation in one of two cases. Usual-type high-grade urothelial carcinoma was seen in six of nine cases. E-cadherin expression: All eight cases of micropapillary urothelial carcinoma were positive for E-cadherin in the micropapillary component and adjacent usual-type urothelial carcinoma. The four cases of plasmacytoid urothelial carcinoma, two cases of urothelial carcinoma with signet ring cell differentiation and two cases of urothelial carcinoma with mixed plasmacytoid and signet ring cell differentiation were all negative for E-cadherin. All nine additional cases of usual-type high-grade urothelial carcinoma were diffusely positive for E-cadherin. E-cadherin is diffusely positive in usual-type urothelial carcinoma and micropapillary urothelial carcinoma, irrespective of pathological stage and angiolymphatic invasion. Loss of E-cadherin expression may be a marker of plasmacytoid and signet ring cell differentiation in urothelial carcinoma.

E-cadherin as an invasion suppressor

The loss of epithelial differentiation in carcinomas, which is accompanied by increased mobility and invasiveness of the tumour cells, is often a consequence of reduced intercellular adhesion. Recent reports have indicated that the primary cause for the 'scattering' of the cells in invasive carcinomas is a disturbance of the integrity of intercellular junctions often involving the cell adhesion molecule E-cadherin. It has also been suggested that during invasion, carcinoma cells convert to a sort of mesenchymal stage, as do normal epithelial cells during development. Permanent and transient molecular mechanisms lead to the impairment of junction integrity of epithelial cells and thus to the progression of carcinomas towards a more invasive state.

Dietary omega-3-polyunsaturated fatty acids prevent the development of metastases of colon carcinoma in rat liver

BACKGROUND

Fish oil consisting of omega-3 polyunsaturated fatty acids (PUFA) seems to reduce the incidence of colon cancer. The effect of PUFAs on metastasis of colon carcinoma is still unclear.

AIM

The study was designed to examine the effects of a diet rich in omega-3-PUFAs on a model of colorectal metastasis.

METHODS

Thirty animals (WAG/Rij) were randomly assigned to receive an omega-3 diet or a control diet to evaluate their effect on tumor growth. The target male rats (WAG/Rij) were fed a diet containing 15% omega-3-fatty acids three days before and 28 days after intervention and the control rats received 15% coconut oil at the same time points. CC 531 cells, a moderately differentiated colon adenocarcinoma, were injected into the spleen of each rat. After 28 days of diet, animals were sacrificed. The tumor growth was evaluated macroscopically and microscopically in liver tissue. The tissue was examined after immunostaining and the use of monoclonal antibodies.

RESULTS

PUFAs decreased the index of tumor load from 1.54 in the controls to 0.79 in the treatment group (P = 0.036). While 69.2% of the control animals were tumor positive, only 21.4% of the target animals showed tumor after omega-3-fatty acid (P < 0.05).

CONCLUSION

We could show that omega-3-fatty acids may decrease malignant metastatic tumor growth in the liver.

The relationship between the expression of E-cadherin and tumor recurrence and progression in high-grade stage T1 bladder urothelial carcinoma

OBJECTIVE

To evaluate the relationship between the expression of E-cadherin (E-CD) and tumor recurrence and progression in patients with high-grade stage T1 urothelial carcinoma of bladder.

METHODS

Fifty-two patients who had primary high-grade stage T1 urothelial carcinoma were enrolled to the study. The pathologic specimens of patients were evaluated and staged as T1a and T1b according to muscularis mucosae involvement by the tumor. The immunohistochemical demonstration of E-CD was accomplished by using immunoperoxidase method and all the specimens were examined under light microscope for E-CD level.

RESULTS

The mean age of the patients was 64.0 +/- 7.7 (range 36-81) years. The mean follow-up period was 56.4 +/- 19.4 (range 14-84) months. Among 52 patients, 27 (52%) of them were stage T1b and 25 (48%) were T1a tumors. The recurrence rates for T1a and T1b groups were 52% (n = 13) and 92.6% (n = 25), respectively (P < 0.05). The expression of E-CD was homogenous in 52% of pT1a and 14.8% of T1b tumors (P < 0.05). In T1a group with recurrence, homogeneous E-CD staining ratio was 30.7% (n = 4/13), but it was 75% (n = 9/12) in T1a patients without recurrence (P < 0.05). In T1b group with recurrence, the homogenous expression of E-CD was 12% (n = 3/25) and the expression of E-CD was heterogenous in 88% (n = 22/25) of them (P < 0.05). In T1a group, progression of the disease was detected in 28% (n = 7/25) of the patients, but disease progression was seen in 55.5% (n = 15/27) of T1b group patients (P < 0.05). In T1a group with progression, heterogeneous E-CD staining ratio was 85.7% (n = 6/7), but it was 80% (n = 12/15) in T1b patients with progression. The effects of tumor number, tumor size and carcinoma in situ presence on recurrence were evaluated within each group. It was determined that parameters such as tumor number and tumor size had no significant effect on recurrence of the groups. The mean survival rates were statistically different between the groups. On multivariate analysis only E-cadherin expression (P = 0.012, odds ratio 6.291, 95% confidence interval for odds ratio 1.303-4.72) and tumor stage (P = 0.003, odds ratio 11.58, 95% confidence interval for odds ratio 2.446-8.542) remained independently significant as predictors of recurrence.

CONCLUSION

E-CD expression was decreased in pathologic specimens of bladder tumor patients with muscularis mucosae involvement and this condition correlated well with tumor recurrence.

Instillation of taurolidine/heparin after laparotomy reduces intraperitoneal tumour growth in a colon cancer rat model

OBJECTIVE

To investigate whether irrigation of the abdominal cavity after laparotomy for caecum resection with taurolidine/heparin or adhesion prophylactic substances reduces intraperitoneal tumour growth or the local recurrence rate in a colon carcinoma rat model.

METHODS

60 BDIX rats underwent caecum resection after intraperitoneal inoculation of 1 x 10(4) colon carcinoma cells (DHD/K12/TRb). Intergel, Interceed, taurolidine/heparin or NaCl 0.9% were intraperitoneally applied after randomisation. Finally, the total number and total weight of intraperitoneal metastases were determined as well as the adhesion score according to Moreno. Metastatic tissue was examined histologically and immunohistochemically (E-cadherin, CD44, beta(1)-integrin).

RESULTS

Taurolidine/heparin significantly reduced not only the total number (3 vs. 11 in the control group) but also the total weight (65 vs. 330 mg) of intraperitoneal metastases in comparison to the control group (p = 0.003 and p = 0.005). E-Cadherin expression in the metastatic tissue of animals treated with taurolidine/heparin was significantly decreased (p = 0.016).

CONCLUSION

Taurolidine/heparin effectively reduces intraperitoneal tumour growth when used as an intraoperative lavage. These results represent a good rationale for intraoperative adjuvant irrigation with taurolidine/heparin during resection of colon cancer.

Influence of intraperitoneal application of taurolidine/heparin on expression of adhesion molecules and colon cancer in rats undergoing laparoscopy

BACKGROUND

Recent experimental studies have shown that intraperitoneal administration of taurolidine/heparin causes a reduction of local tumor growth after laparoscopy in rat models. It might be that the anti-adherent activities of these agents are responsible for this effect. In this study we investigated the adhesion molecules E-cadherin, beta1-integrin, and CD44.

MATERIALS AND METHODS

Following a 10,000 colon adenocarcinoma cells' (DHD/K12/TRb) intraperitoneal application a cecum resection and a partial parietal peritoneum resection (1 x 1 cm) were performed using a three trocar technique in 30 BD IX rats. After randomization in two groups, the cecum suture line and the parietal peritoneal defect were either lavaged with 1 mL of 0.5% taurolidine/10 IU heparin or with equal amounts of 0.9% normal saline solution. Rats were sacrificed four weeks after operation and total tumor growth was determined. E-cadherin, beta1-integrin, and CD44 were assessed immunohistochemically on the tumor tissue.

RESULTS

The expression of E-cadherin was significantly reduced to 46.7% (complete loss of staining) in the taurolidine/heparin group. Although no significant difference was detected concerning the beta1-integrin and CD44 expression, a slightly reduced expression level with 26.7% of negative staining in metastases of the taurolidine/heparin group was observed. The total tumor weight (171.1 +/- 181.2 mg) as well as the total number of tumor lesions was also reduced by the substances compared to the control group (283.2 +/- 91.4 mg).

CONCLUSIONS

Taurolidine/heparin led to a significant reduction of local tumor growth. Additionally a reduction of the expression of E-cadherin was observed. However, the biological behavior of this molecule is multivariant, controversial and still unclear. Further studies should elucidate its role in the epithelial tumor genesis.

Expression of E-cadherin in gastric carcinoma and its correlation with lymph node micrometastasis

AIM: To examine the expression of E-cadherin in the primary tumor and to evaluate its relationship with lymph node micrometastasis (LNM).

METHODS: The authors studied 850 lymph nodes resected from 30 patients with gastric carcinoma who underwent gastrectomy with lymphadenectomy using reverse transcription polymerase chain reaction (RT-PCR) assay in addition to H&E staining. Cytokeratin-20 (CK-20) gene marker was used in this assay. The level of E-cadherin expression in the primary tumor was examined by immunochemical technique (EliVision^TM plus).

RESULTS: LNM was detected in 77 (12.5%) lymph nodes of 14 patients (46.7%) with gastric carcinoma. The incidence of LNM was significantly higher in the diffuse type (12 of 19 cases, 63.2%) than in the intestinal type of gastric carcinoma (2 of 11 cases, 18.2%, P = 0.026). The incidence of LNM also increased in accordance with the depth of tumor invasion. The loss of expression of E-cadherin in primary tumors was found in 14 (46.7) of 30 tumors. The absence of E-cadherin expression was significantly associated with the Lauren classification (P = 0.026), lymph node metastasis (P = 0.011), the grade of differentiation (P = 0.004) and the lymphatic invasion (P = 0.001). Expression of E-cadherin was negative in 10 (71.4%) of the 14 patients with LNM, and in 4 (25%) of the 16 patients without LNM (P = 0.026).

CONCLUSION: The current results indicate that the RT-PCR assay is useful for the detection of LNM and can significantly increase the detection rate of lymph node metastasis in patients with gastric carcinoma. The Lauren classification and depth of tumor invasion are significantly associated with lymph node micrometastases. Our findings also indicate that E-cadherin may play an important role in determining the growth type and differentiation of gastric carcinoma. The loss of E-cadherin expression may contribute to LNM.

Expression of E-cadherin in human colorectal cancer

AIM

To investigate the expression of E-cadherin, a calcium-dependent cell-cell adhesion molecule in colorectal carcinoma. Antibodies to E-Cadherin were used to establish the association of their expression with the clinicopathological characteristics of this disease using immunohistochemical methods.

METHODS

Immunohistochemical analysis for E-cadherin was carried out in formalin-fixed, paraffin-embedded sections of neoplastic colorectal tissues and non-neoplastic ones adjacent to the lesion from 49 patients who underwent surgery, by the standard peroxidase-antiperoxidase method. Expression of this antigen in normal and malignant epithelium and stromal cells was compared.

RESULTS

Both neoplastic and normal tissues showed expression of E-cadherin. There was, however, higher expression of E-cadherin in epithelial cells in both tumour and normal tissues than stromal cells. The percentage of expression in epithelial cells of well-differentiated tumours was significantly higher than moderately differentiated tumours. Loss of normal membranous expression and the presence of cytoplasmic and mixed staining were found frequently in tumour tissues (p = 0.004). This loss of membranous expression, however, did not correlate with Duke's staging, tumour grade, sex, size or site of the tumour.

CONCLUSION

This study suggests that the lower expression of E-cadherin in less differentiated tumours may explain their aggressive nature, although loss of membranous expression was not significantly correlated to Duke's staging, tumour grade, sex, size and site of tumour.

E-cadherin and cytokeratin subtype profiling in effusion cytology

Diagnostic utility of E-cadherin (E-CD) and cytokeratin (CK) subtype profiling in effusion cytology was investigated, employing immunocytochemistry on cellblock sections available from 211 metastatic carcinomas (MC), 6 mesotheliomas and 73 reactive mesothelial hyperplasias (MH). E-CD and monoclonal carcinoembryonic antigen (mCEA) stained 85% (120/141) and 65% (138/211) of MC, respectively. E-CD staining of MC was frequently heterogeneous (76/120) and absent in all anaplastic carcinomas (0/2). E-CD stained none (0/57) of MH while mCEA and epithelial membrane antigen (EMA) stained 12% (9/73) and 32% (16/32) of MH, respectively. Of 6 mesotheliomas, E-CD focally stained in 2 while mCEA stained none and EMA stained all. CK20 and CK17 stained none of MH or mesotheliomas. CK20 stained 15% of MC and CK 17 stained 22% of MC. CK5/6 and high molecular weight CK stained all mesotheliomas, 56% and 88% of MH, 26% and 39% of MC, respectively. MC showed predominant CK7+/20-expression, with the exceptions of MC from mucinous type of colon/rectum and ovary showing predominant CK20 positive. E-CD may be a useful positive marker for MC in effusion cytology, although it may focally stain in some mesotheliomas. Any positive staining for CK20 of MC suggests MC from the gastrointestinal tract or ovary among others.

Increased peritoneal dissemination after laparotomy versus pneumoperitoneum in a mouse cecal cancer model

BACKGROUND

The effect of carbon dioxide (CO(2)) pneumoperitoneum on the liberation of cancer cells from the primary tumor is not clear. This study investigated the influence of laparotomy versus CO(2) pneumoperitoneum on the progression of colon cancer with serosal invasion in a mouse model.

METHODS

Pieces of human colon adenocarcinoma (HT29) tumor were implanted in the cecal wall of 45 BALB/c nude mice. Each mouse underwent one of three procedures: laparotomy, CO(2) pneumoperitoneum, or anesthesia (control). Three weeks later, the size and weight of cecal tumors, the number of nodules, and the tumor volume score of peritoneal dissemination were examined. Another 45 mice were treated in the same way. The cecal tumor was resected on days 1, 3, or 5 after treatment. Total RNA was isolated from the resected tumors. The expression of E-cadherin and beta-1 integrin messenger RNA (mRNA) was examined by semiquantitative real-time reverse transcriptase-polymerase chain reaction assay.

RESULTS

Significantly more nodules of peritoneal dissemination were found in the laparotomy group than in the control group (p < 0.05). The tumor volume score of peritoneal dissemination in the laparotomy group was significantly higher than in the other two groups (p < 0.05). The expression of E-cadherin mRNA at day 5 in the laparotomy group was significantly less than in the other two groups (p < 0.05). There were no differences in beta-1 integrin among three groups.

CONCLUSIONS

Peritoneal dissemination was more extensive after laparotomy than after CO(2) pneumoperitoneum in a mouse model of cecal cancer with serosal invasion. Decreased expression of E-cadherin mRNA in tumors after laparotomy, but not after CO(2) pneumoperitoneum, may be associated with the increase in peritoneal dissemination.

Expression of E-cadherin, and CD44s and CD44v6 and its association with prognosis in head and neck cancer

OBJECTIVES

In the current study, the expression of E-cadherin, CD44s, and CD44v6 has been noted as markers for tumor metastasis and prognosis in several tumors, so we examined whether or not E-cadherin, CD44s, and CD44v6 are useful markers for evaluating the prognosis of mesopharyngeal cancer patients.

METHODS

The expression of E-cadherin, CD44s, and CD44v6, was evaluated immunohistochemically using monoclonal antibodies against epitopes of standard and variant proteins, in paraffin-embedded mesopharyngeal cancer tissues from 57 patients who had received curative therapy.

RESULTS

Tumor tissues from 47 (82.5%) patients showed positive immunoreactivity with monoclonal antibody against E-cadherin, 43 (75.4%) patients showed positive expression with CD44, and 45 (78.9%) patients showed positive expression with CD44v6. The expression of CD44v6 was slightly correlated with tumor volume, and lymph node metastasis, and stage classification (P > 0.05). However, there was no significant correlation between the expression of E-cadherin, CD44s and CD44v6 and clinicopathological characteristics. Concerning the prognosis, the survival period of patients with CD44s positive tumors was shorter than that of patients with CD44s negative tumors (18.2% versus 52.1%, 5-year survival, P > 0.05). The survival period of patients with CD44v6 positive tumors was also shorter than that of patients with CD44v6 negative tumors (12.8% versus 55.6%, 5-year survival, P > 0.05).

CONCLUSION

These results suggest that CD44v6 may be related to tumor invasion and metastasis, and both CD44s and CD44v6 may be useful markers for poor prognosis in head and neck cancer.

Adhesion-related proteins E-cadherin, P-cadherin, CD44, and CD44v6, and antimetastatic protein nm23H1 in complete hydatidiform moles in relation to invasion potential

Cell adhesion has an essential role in regulating metastasis, and loss of cell adhesion is a classic feature of invasion. There is currently a great deal of interest in the role of adhesion proteins and the antimetastatic protein nm23H1 in the progression of cancer. However, reports on the expression of these proteins in complete hydatidiform moles (CHMs) are limited. In the present study, expression of the adhesion molecules E-cadherin, P-cadherin, CD44, and CD44v6, and the antimetastatic protein nm23H1 was assessed in relation to the invasive potential of CHMs. This is the first report on the expression of these proteins in CHMs. Immunohistochemical assessment was carried out in CHMs (105 cases including 15 cases of invasive moles) and compared with that of gestational age-matched normal placentae (95 cases). The expression of the adhesion proteins ranged from mild to moderate intensity with a general down-regulation in the molar trophoblasts, the down-regulation in CD44 and CD44V6 being highly significant. No relation was, however, noticed with the invasiveness or the persistence of the disease. nm23H1 protein, on the other hand, was significantly down-regulated in the molar trophoblasts with none of the invasive lesions showing intense expression. The study thus suggests down-regulation of adhesion proteins, especially that of CD44 and CD44v6, to be an early step in the transformation to molar placenta with reduced expression of nm23H1 conferring an invasive potential to the trophoblasts.

Neoexpression of N-cadherin in E-cadherin positive colon cancers

In our study, we aimed to investigate the expression of N-cadherin and E-cadherin and their dependency on epithelial-mesenchymal transition regulators SNAI1, SIP1 and TWIST in human colon cancer. Expression of E-cadherin and N-cadherin was examined by immunohistochemistry in 80 colon carcinomas by using paraffin embedded and formalin fixed tissues. Those cases were partly analyzed for mRNA expression of N-cadherin (42 cases), TWIST (18 cases), SNAI1 (25 cases) and SIP1 (25 cases) by real-time quantitative RT-PCR. Additionally, colon carcinomas that showed amplification of 20q13, the localization of the human SNAI1 gene, were examined. We found cytoplasmic and/or membrane-associated immunoreactivity of N-cadherin in 35/80 (44%) of the cases. However, there was no correlation to upregulated TWIST mRNA levels, as we have shown previously for diffuse-type gastric cancers with abnormal N-cadherin expression. Reduced and/or cytoplasmic E-cadherin immunoreactivity was detected in 19% (15/80) of the cases. Expression of SNAI1 or SIP1 mRNA was not seen in any of the 25 cases analyzed. There was no correlation between amplification of 20q13 and SNAI1 mRNA expression. Remarkably, N-cadherin was almost exclusively expressed in those cases showing normal E-cadherin immunoreactivity, suggesting a mutual exclusion between abnormal E-cadherin reduction and upregulation of N-cadherin. For the first time, we postulate a role for N-cadherin in primary colon cancer progression, which may be similar to the effect discovered by others in breast cancer cell lines, where coexpressed N-cadherin can exert a dominant function over E-cadherin's adhesive function and thus promote tumor invasiveness.

Heterogeneous expression and association of beta-catenin, p16 and c-myc in multistage colorectal tumorigenesis and progression detected by tissue microarray

Most colorectal carcinomas (CRCs) arise from adenomas through an archetypal pathogenic pathway, the adenoma-carcinoma-metastasis sequence. Aberrant expression of beta-catenin, p16, E-cadherin and c-myc appears to have played important roles in the development and/or progression of CRC, but their precise distribution pattern and associations in different pathologic loci along CRC's pathogenic pathway have not been thoroughly examined. In this study, a tissue microarray (TMA) containing 85 advanced CRCs in different Dukes stages was constructed. In each of 85 cases, tissue specimens from normal mucosa and primary carcinomas in different layers of the bowel wall were included in the TMA. Tissue specimens from matched adenoma, lymph node metastases and distant metastases were obtained from 22, 21 and 21 cases, respectively. Expression patterns of beta-catenin, p16, E-cadherin and c-myc were evaluated by immunohistochemistry. The results revealed that nuclear expression of beta-catenin, p16 and c-myc was quantitatively increased from normal mucosa to premalignant adenoma, primary carcinoma and lymph node metastatic carcinoma; the frequency of nuclear overexpression of beta-catenin and p16 in lymph node metastases was significantly higher than that in distant metastases (p < 0.05). These results suggest an association between nuclear overexpression of beta-catenin and/or p16 and CRC lymph node metastasis but not distant metastasis. The results also showed that correlative high nuclear expression of beta-catenin and c-myc was observed in primary carcinomas involving the serosa and lymph node metastases (p < 0.05) but not in other pathologic regions of CRCs, suggesting that the tumor microenvironment in different pathologic loci of colorectal tumorigenesis and progression may influence c-myc responsiveness to beta-catenin/Tcf activation.

Value of E-cadherin and N-cadherin immunostaining in the diagnosis of mesothelioma

Distinguishing between epithelioid mesothelioma and pulmonary adenocarcinoma involving the pleura can be difficult on routine histological preparations. This differential diagnosis can be greatly facilitated by using immunohistochemical markers. E-cadherin and N-cadherin are among the newly described markers that have been proposed as potentially useful in the diagnosis of mesothelioma. E-cadherin and N-cadherin are members of the cadherin family of calcium-dependent cell adhesion molecules that play an important role in the embryogenic development and maintenance of normal tissue. Although several investigations have indicated that immunostaining for these markers can be useful in discriminating between mesotheliomas and adenocarcinomas, others have not confirmed this observation. In an attempt to resolve this controversy, the present study investigated 31 epithelioid mesotheliomas and 29 pulmonary adenocarcinomas for E-cadherin and N-cadherin expression using the 5H9, HECD-1, and clone 36 anti-E-cadherin antibodies, and the 3B9 and clone 32 anti-N-cadherin antibodies. Among the mesotheliomas, 68% reacted with the clone 36, 52% reacted with the HECD-1, and 19% reacted with the 5H9 anti-E-cadherin antibodies, and 74% reacted with the 3B9 and 71% reacted with the clone 32 anti-N-cadherin antibodies. Of the adenocarcinomas, 93% stained with the clone 36, 90% reacted with the HECD-1, and 90% reacted with the 5H9 anti-E-cadherin antibodies, 45% reacted with the clone 32 and 34% reacted with the 3B9 anti-N-cadherin antibodies. Based on the frequent strong reactivity with adenocarcinomas but not with mesotheliomas, it is concluded that only the 5H9 anti-E-cadherin antibody may have some utility in discriminating between epithelioid pleural mesotheliomas and pulmonary adenocarcinomas. The causes of the disparate results reported in the literature on the value of E-cadherin and N-cadherin immunostaining in distinguishing between mesotheliomas and pulmonary adenocarcinomas are unclear, but a significant factor appears to be differences in the reactivity of the antibodies used.

Expression of E-cadherin, alpha-catenin, and beta-catenin in the process of lymph node metastasis in oral squamous cell carcinoma

Regional lymph node metastasis is a very important prognostic indicator. In the metastatic process, reduction in cell to cell adhesion including E-cadherin-catenin cell adhesion complex is an essential step. We investigated immunohistochemical expression of E-cadherin, alpha-catenin and beta-catenin in 159 tissue samples from patients with oral squamous cell carcinoma and examined the correlation between their expressions and the presence of regional lymph node metastasis. Significantly greater reduction in expression levels of E-cadherin, alpha-catenin and beta-catenin was found in the metastatic group (n=64) compared to the nonmetastatic group (n=95) (P=0.007, 0.001, 0.001, respectively). However, there was no significant correlation between their expressions and the features of the regional metastasis, the number of metastatic lymph nodes or the presence of extracapsular metastasis. These data suggest that evaluation of the immunohistochemical expression of E-cadherin, alpha-catenin and beta-catenin is extremely valuable for the diagnosis of metastatic occurrence.

Effects of carbon dioxide and nitrogen on adhesive growth and expressions of E-cadherin and VEGF of human colon cancer cell CCL-228

AIM: To study the effects of carbon dioxide on the metastatic capability of cancer cells, and to compare them with that of nitrogen.

METHODS: The colon cancer cell CCL-228 was treated with 100% carbon dioxide or nitrogen at different time points and then cultured under normal condition. Twelve hours after the treatment, the survival rates of suspension cells and the expressions of e-cadherin and VEGF were examined.

RESULTS: After 60 min of carbon dioxide and longer time of nitrogen treatment, the suspended cells increased and the expression of e-cadherin decreased while the expression of VEGF was enhanced significantly. And the effects of nitrogen were similar to, but weaker than, those of carbon dioxide.

CONCLUSION: Carbon dioxide may improve the metastatic capability of cancer cells and its effects are significantly stronger than that of nitrogen. A sequential use of carbon dioxide and nitrogen in pneumoperitoneum may take the advantage of both gases.

Cell-cell adhesion in the normal ovary and ovarian tumors of epithelial origin; an exception to the rule

Cells are held together either by direct cell-cell contact or adhesion to extra-cellular matrix. Cell-cell adhesion in epithelial cell sheets consists of junctions, i.e. tight-, adherens- and gap-junctions. The adherens junctions, which are build up by the cadherin/catenin complex, are the main topic of this review, especially the aspect of its role in ovarian tumor biology. The ovarian surface epithelium is the origin for approximately 90% of the malignant ovarian tumors. The tumors arise from the inclusion cysts, localized in the ovarian stroma and grow solid, cystic or in mixed formations. Intra-abdominal spread of the ovarian cancer is common and this is a process that theoretically could be closely connected with impaired cell-cell adhesion. However, as we stand today, descriptive and functional studies on the cadherin-catenin complex and its cell signaling role in ovarian tumorigenesis reveals data that suggests a conversion of the mesothelial-like cells of the ovarian surface to a more epithelial phenotype with normal cell-cell adhesion prior to tumor differentiation. In later stages, invasive ovarian tumors still strongly express several cadherins, which are contrary to many other tumors, i.e. prostate and thyroid adenocarcinomas.

Gains and losses of adhesion molecules (CD44, E-cadherin, and beta-catenin) during oral carcinogenesis and tumour progression

The aim of this study was to define whether or not the impaired expression of CD44, E-cadherin (E-cad), and beta-catenin (beta-cat) correlates with the clinical evolution and prognosis of oral cancer. Ninety-three primary oral squamous cell carcinomas (OSCCs) with tumour-adjacent normal and/or dysplastic mucosa, 30 associated metastases, and 12 recurrences were immunostained for CD44s, -v3, -v4, -v5, -v6, -v7, -v9, E-cad, and beta-cat. In non-neoplastic epithelium, all molecules investigated were constitutively expressed in the basal layers. In the majority of dysplasias, immunoreactivity for all adhesion molecules was increased, but there was restricted loss for CD44s, E-cad, and beta-cat in a few cases. In carcinomas, a striking accumulation of CD44s, v3, v4, v9 and a loss of E-cad/beta-cat were observed at the invasive tumour front. In metastases and recurrences, besides a loss of CD44s, v4, v7, and E-cad, a significant increase of v9 was recorded, whereas CD44v5 and v6 remained unchanged. Clinically, reduced expression of CD44v3, E-cad, and changes of CD44v9 phenotype within the primary tumours correlated significantly with poor prognosis; decreased beta-cat expression was a predictive marker for nodal metastases. These findings indicate that there is some perturbed expression of adhesion molecules during the stepwise course of oral carcinogenesis and tumour progression. Distinct phenotypic alterations project poor prognosis, while others predict metastasis. Some of these restricted molecular changes may serve as potential targets for future antibody-based tumour therapy.

The expression of E-cadherin and catenins in colorectal tumours from familial adenomatous polyposis patients

Familial adenomatous polyposis patients (FAP) harbour a germline mutation of the adenomatous polyposis coli gene (APC), and APC mutations are early events in the development of sporadic colorectal neoplasms. The APC protein interacts with beta-catenin and gamma-catenin and APC mutations are believed to play a role in the altered levels of beta-catenin in colorectal tumours. Immunohistochemical studies have shown changes in the expression and distribution of E-cadherin and catenins in sporadic colorectal neoplasms. This study assessed the expression and distribution of E-cadherin and catenins in colorectal neoplasms and non-neoplastic mucosa from FAP patients. The expression and cellular distribution of E-cadherin and catenins were studied by immunohistochemistry in 61 adenomas, five carcinomas, and non-neoplastic mucosa from 18 FAP patients. mRNA levels in the carcinomas were studied by in situ hybridization. The expression of E-cadherin and catenins was increased in over 80% of the adenomas, with evident cytoplasmic immunoreactivity. There was increased expression of E-cadherin and catenin in the carcinomas, with a notable increase in the levels of mRNA, in comparison with the non-neoplastic mucosa.

Deranged expression of the E-cadherin/beta-catenin complex and the epidermal growth factor receptor in the clinical evolution and progression of oral squamous cell carcinomas

BACKGROUND

Deranged expression and function of the E-cadherin/beta-catenin (E-cad/beta-cat) complex and the epidermal growth factor receptor (EGFR) have been implicated in the development and progression of carcinomas.

METHODS

To estimate the role of these molecules in oral cancer, we investigated 75 primary oral squamous cell carcinomas (OSCCs) with adjacent normal and/or dysplastic mucosa, 30 paired metastases and 12 recurrences by immunohistochemistry.

RESULTS

All three molecules were constitutionally expressed in the basal/parabasal layers of tumour adjacent 'normal' epithelium, in contrast to a significant increase of EGFR and heterogeneous expression of E-cad/beta-cat in dysplasia. In OSCCs, over-expression of EGFR correlated significantly with lower tumour grade and poor prognosis, loss of E-cad was a significant marker for shortened survival, reduced beta-cat staining was a predictive marker for lymph node metastasis.

CONCLUSIONS

There is a perturbance in intercellular adhesion molecules and EGFR expression/function in oral cancer with major clinical impact. E-cad and beta-cat seem to inhibit EGFR to enhance the progression of OSCCs.

The expression of E-cadherin and catenins in sporadic colorectal carcinoma

The E-cadherin/catenin complex plays a major role in epithelial cell-cell adhesion. Immunohistochemical studies have highlighted perturbation in the expression and distribution of E-cadherin and catenins in sporadic colorectal neoplasms. In this study, we compared the expression of E-cadherin and catenins (alpha-, beta-, and gamma-catenin) in 30 sporadic colorectal carcinomas with that in the adjacent nonneoplastic mucosa and assessed whether any perturbation in the level of expression occurred at the messenger RNA (mRNA) or protein level. We also compared the expression of E-cadherin and catenins in 13 lymph node deposits and the primary tumors. Immunohistochemistry was used to study the level of expression and cellular distribution of E-cadherin and catenins. Levels of mRNA were studied by in situ hybridization. E-cadherin and catenin immunoreactivity was increased with cytoplasmic accumulation in more than 85% of the neoplasms. There were marked increases in the levels of mRNA in the carcinomas compared with the nonneoplastic mucosa. Nuclear localization of beta-catenin was higher at the invasive margin of some tumors, but expression of E-cadherin and catenin transcripts in the lymph node deposits showed no consistent relationship to that in the primary tumors.

Changes of E-cadherin and beta-catenin in human and mouse intestinal tumours

An immunohistochemical analysis of E-cadherin and beta-catenin was performed in human colorectal cancer as well as in surrounding normal intestinal tissue. We also analysed the expression of these two cell adhesion proteins in transgenic Apc1638N mice as a model of human familial adenometous polyposis syndrome. In the normal intestinal mucosa of both species, E-cadherin and beta-catenin were localized along the lateral plasma membranes of epithelial cells. In intestinal tumour cells, however, they were also present in the cytoplasm. The expression of both proteins was reduced in human and mouse tumours. The pattern of their distribution was frequently heterogenous with strongly positive cells in a mosaic of negative ones. Further, E-cadherin and beta-catenin expression did not correlate to the Duke's staging of tumours and therefore neither can be used as prognostic criteria.

Detection and prediction of micrometastasis in the lymph nodes of patients with pN0 gastric cancer

BACKGROUND

The clinicopathologic significance of micrometastasis (MM) and tumor cell microinvolvement (TCM) in regional lymph nodes as identified by immunohistochemical staining for cytokeratin expression was evaluated in patients with node-negative gastric cancer.

METHODS

MM was defined as tumor cells with stromal reaction, and TCM was defined as individual tumor cells without stromal reaction. We investigated 1761 lymph nodes obtained from 67 gastric cancer patients whose diagnosis showed no lymph node metastasis by routine histological examination. The depth of tumor invasion was T1 (submucosa) in 33 patients and T2 (muscularis propria and subserosa) in 34 patients. The lymph nodes were examined immunohistochemically for the presence of tumor cells using anti-cytokeratin AE1/AE3 monoclonal antibody. Both the biopsy tumor specimens obtained prior to surgery and the resected primary tumors were immunostained with E-cadherin (E-cad) monoclonal antibody.

RESULTS

Thirty (1.5%) of the 1761 lymph nodes showed MM and/or TCM. MM with or without TCM was found in 10 patients, and TCM alone was found in 4 patients; 6 (18.2%) of the 33 patients with T1 tumor and 8 (23.5%) of the 34 patients with T2 tumor had occult lymph node metastasis. The 5-year survival rate was worse among those with MM with or without TCM, than among those without MM. Nearly all of the patients with MM and/or TCM had reduced or negative E-cad expression in the primary tumor.

CONCLUSIONS

We demonstrated that the incidence of MM and/or TCM in the lymph nodes of patients with gastric cancer is quite high, and that such metastasis is associated with the prognosis of patients with pN0. Examination of E-cad expression in biopsy tumor specimens may be useful for predicting MM and/or TCM.

E-cadherin and adenomatous polyposis coli mutations are synergistic in intestinal tumor initiation in mice

BACKGROUND & AIMS

Inactivation of the adenomatous polyposis coli (APC) gene is observed at early stages of intestinal tumor formation, whereas loss of E-cadherin is usually associated with tumor progression. Because both proteins compete for the binding to beta-catenin, an essential component of the Wnt signaling pathway, reduction of E-cadherin levels in an Apc mouse model could influence both tumor initiation and progression. In addition, loss or haploinsufficiency of E-cadherin may affect tumorigenesis by altering its cell-adhesive and associated functions.

METHODS

Apc1638N mice were bred with animals carrying a targeted E-cadherin knockout mutation.

RESULTS

Double heterozygous animals showed a significant 9-fold and 5-fold increase of intestinal and gastric tumor numbers, respectively, compared with Apc1638N animals. The intestinal tumors of both groups showed no significant differences in grading and staging. Loss of heterozygosity analysis at the Apc and E-cadherin loci in both intestinal and gastric Apc(+/1638N)/E-cad(+/-) tumors revealed loss of the wild-type Apc allele in most cases, whereas the wild-type E-cadherin allele was always retained. This was supported by a positive, although reduced, staining for E-cadherin of intestinal tumor sections.

CONCLUSIONS

Introduction of the E-cadherin mutation in Apc1638N animals enhances Apc-driven tumor initiation without clearly affecting tumor progression.

BAG-1 expression correlates highly with the malignant potential in early lesions (T1 and T2) of oral squamous cell carcinoma

BAG-1 is a Bcl-2-binding protein that functions as an anti-apoptotic molecule. In this report we show a possible correlation between BAG-1 expression levels and the probability of oral squamous cell carcinoma (SCC) progression. We investigated BAG-1 expression levels in 22 patients diagnosed with early lesions (T1 and T2) of oral SCCs using immunohistochemistry and western blotting. High steady-state levels of BAG-1 were detected in 13 out of 22 cases (59%). High BAG-1 expression was observed more frequently in cases with nodal metastasis (89%) than in those without nodal metastasis (38%) (P<0. 03), suggesting that BAG-1 expression levels may correlate with the pathological stage of oral SCCs. Furthermore, BAG-1 expression levels correlated with the WHO grade, i.e. 45% in grade-I cases as opposed to 72% in grade-II cases (P<0.02). These data suggest that an analysis of BAG-1 expression may be useful in establishing a prognosis for patients with oral SCCs, and especially in predicting the metastatic potential of SSCs.

Role of E-cadherin in peritoneal dissemination of the pancreatic cancer cell line, panc-1, through regulation of cell to cell contact

The present study was designed to clarify the molecules responsible for peritoneal dissemination of cancer cells. We established sublines with high (HP cells) and low (LP cells) passing activity through the membrane of a transwell chamber. The cell lines were established from the human pancreatic cancer cell line, Panc-1. LP cells demonstrated an octagonal shape and tight adhesion, whereas HP cells exhibited a spindle shape and grew with less cell-cell contact in vitro. It was found that HP cells demonstrated a high degree of peritoneal dissemination in nude mice following peritoneal injection of these cells compared to LP cells. We subsequently investigated the expression of certain adhesion molecules. Consequently, we found that LP cells exhibited a stronger expression of E-cadherin than HP cells. On the other hand, there was no difference in the expression of CD44H and beta1 integrin between these two sublines. Passing activity of LP cells through the membrane of the invasion chamber increased to nearly equal levels with HP cells following treatment with anti-human E-cadherin antibody. Moreover, transfection of mouse E-cadherin cDNA into HP cells reduced both passing activity through the membrane of the invasion chamber and peritoneal dissemination in nude mice to levels similar to that of LP cells. In conclusion, these results indicated that loss of E-cadherin facilitates both passing activity in an invasion chamber and peritoneal dissemination, playing a causative role in peritoneal dissemination of cancer cells.

E-cadherin expression in skin tumors using an AMeX immunohistostaining method

The AMeX (acetone-methylbenzoate-xylene) method results in good preservation of tissue and morphological details, almost equivalent to that of routinely processed formalin-fixed and paraffin-embedded tissue specimens, and of antigenicity equivalent to that of fresh frozen tissue specimens. It has been reported that the expression of the cell-cell adhesion molecule E-cadherin is often decreased in some types of carcinomas. A decrease in E-cadherin expression is associated with the invasive or metastatic potential of tumor cells. We immunohistochemically examined the expression of E-cadherin with anti-E-cadherin monoclonal antibody in various skin tumors (25 basal cell carcinomas, 11 squamous cell carcinomas, 9 keratoacanthomas, and 11 Bowen's disease) using the AMeX method and found that this method preserved antigenicity well without pretreatment. E-cadherin expression was decreased in 18.2% of squamous cell carcinomas and 33.3% of keratoacanthomas. On the other hand, it was preserved in almost all Bowen's disease and basal cell carcinomas. From the results of our study, we suggest that Bowen's disease and basal cell carcinoma do not have much metastatic potential due to retention of high levels of E-cadherin expression. We hope to apply the AMeX method to other immunohistochemical examinations because this is a very useful staining method.

An immunohistochemical study of E-cadherin expression in human squamous cell carcinoma of the skin: relationship between decreased expression of E-cadherin in the primary lesion and regional lymph node metastasis

E-cadherin is a Ca(2+)-dependent, intercellular adhesion molecule that is specifically expressed in epithelial tissues and is essential for maintaining intercellular connections. It has been reported that E-cadherin expression of tumor cells is often decreased in some types of metastasizing carcinomas as compared with those without metastasis. We immunohistochemically examined the expression of E-cadherin with anti-E-cadherin monoclonal antibody and compared primary lesions of human squamous cell carcinoma of the skin (SCC) with regional lymph node metastasis to those without regional lymph node metastasis. Tumor samples from fifty-five cases of SCC (32 cases of SCC without metastasis and 23 cases with metastasis) were formalin-fixed, paraffin-embedded, and examined. E-cadherin was reduced or absent in 39 (70.9%) out of 55 cases of SCC, and in 21 (91.3%) of 23 cases with regional lymph node metastasis. Our results suggest that the decreased expression of E-cadherin in the primary lesion is correlated with regional lymph node metastasis in SCC and that it is more frequently correlated with well-differentiated than with poorly differentiated SCC. E-cadherin may be useful as a marker for metastatic potential in well-differentiated SCC.

Cadherin-catenin expression in primary colorectal cancer: a survival analysis

Both cell adhesion and cell signalling events are mediated by components of the cadherin-catenin complex. Loss of expression of the components of this complex have been shown to correlate with invasive behaviour in many tumour types although their exact role in colorectal cancer remains unclear. Immunohistochemical analysis of the expression of components of the cadherin-catenin complex in colorectal cancers from 60 patients was undertaken. Loss of memberanous expression of E-cadherin, alpha-catenin and beta-catenin was demonstrated in 52%, 85% and 40% of tumours respectively. Focal nuclear expression of beta-catenin (< 75% of cells per section), usually associated with cytoplasmic expression, was clearly demonstrated in 19 (32%) tumours while widespread nuclear expression (> 75% of tumour cells per section) was seen in 11 (18%) tumours. Loss of membranous alpha-catenin expression significantly correlated with tumour de-differentiation (P = 0.009). There was a trend towards an association between advanced tumour stage and loss of membranous expression of alpha-catenin or beta-catenin, although these associations were not statistically significant. Univariate analysis revealed that advanced Dukes' stage, tumour de-differentiation, loss of membranous beta-catenin expression, cytoplasmic beta-catenin expression and widespread nuclear expression of beta-catenin all correlated with short survival following apparently curative resection of the primary tumour. However, only Dukes' stage (P = 0.002), tumour grade (P = 0.02) and widespread nuclear expression of beta-catenin (P = 0.002) were independent predictors of short survival. Disturbed growth signalling events in colorectal tumours are thought to result in nuclear accumulation of beta-catenin. Consequently, tumours with widespread nuclear expression of beta-catenin are likely to have severely abnormal growth characteristics, and which therefore might be predictive of short survival in these patients.

Cadherin and catenin expression in normal human bronchial epithelium and non-small cell lung cancer

Cadherins are transmembrane cell adhesion molecules (CAMS) that mediate cell-cell interactions and are important for maintenance of epithelial cell integrity. This function is dependent on an indirect interaction between the cytoplasmic domain of the cadherin molecule with three cytoplasmic proteins known as alpha-, beta-, and gamma-catenin (-cat). Growing evidence suggests that alterations in cadherin or catenin expression or function may be important to the development of an invasive or metastatic phenotype. Immunohistochemical techniques were used to study the expression of the two major epithelial cadherins, E-cadherin (E-cad) and P-cadherin (P-cad) as well as alpha- and gamma-cat in normal bronchial epithelium and in a series of carefully TMN-staged pulmonary adenocarcinomas (n = 21) and squamous cell carcinomas (n = 7). The cadherin profile of normal pseudostratified bronchial epithelium was heterogeneous. Basilar cells strongly expressed P-cad, alpha- and gamma-cat, while columnar cells moderately expressed E-cad, alpha- and gamma-cat. In contrast to other epithelial tumors, E-cad on non-small cell lung carcinomas was actually upregulated, however, a decrease in P-cad expression was noted in 68%. At least one cadherin or catenin was downregulated, compared to normal bronchial epithelium, in 82% of tumors examined. With the exception of an association between loss of P-cad expression and poorly differentiated state, changes in cadherin and catenin expression levels were not significantly correlated to tumor stage, cell type, or nodal status. These findings illustrate that alteration of expression of cadherins and catenins are often found in non-small cell lung carcinoma when compared to the progenitor bronchial epithelium, and may play a role in the development of the malignant phenotype.

The impact of transurethral resection of bladder tumour on serum levels of soluble E-cadherin

OBJECTIVE

To evaluate soluble E-cadherin (sE-cadherin) as a potential tumour marker in patients with transitional cell carcinoma (TCC) of the bladder (previously shown to correlate with tumour grade, number of Ta/T1 tumours at presentation and a positive 3-month check cystoscopy) by assessing its serum concentration in relation to transurethral resection of bladder tumour (TURBT).

PATIENTS AND METHODS

Samples of venous blood were obtained from 25 patients with bladder cancer: (i) before cystoscopy/TURBT: (ii) intraoperatively, during tumour resection; and (iii) on the first day after surgery. Levels of sE-cadherin were measured using an enzyme-linked immunosorbent assay.

RESULTS

Sixty-three serum samples from patients with TCC of the bladder were available for analysis (23 before, 21 during and 19 after surgery). Patients with G2/3 tumours had significantly higher median preoperative levels of sE-cadherin (16.37 and 13.03 microg/mL, respectively) than those with G1 tumours (9.493 microg/mL; P = 0.0164). There was no correlation between tumour stage and preoperative sE-cadherin concentration. The median concentrations of sE-cadherin were not significantly different before, during and after TURBT.

CONCLUSIONS

This study confirmed the previous finding that higher levels of serum sE-cadherin correlate with increasing tumour grade but not with clinicopathological stage. Serum sE-cadherin levels are not significantly altered by TURBT in the immediate perioperative period.

Immunophenotypic and prognostic analysis of E-cadherin and beta-catenin expression during breast carcinogenesis and tumour progression: a comparative study with CD44

AIMS

This study was performed to investigate whether immunohistochemical expression of E-cadherin (E-cad) and beta-catenin (beta-cat) in conjunction with CD44 may correlate with the clinical evolution and prognosis of breast cancer.

METHODS AND RESULTS

One-hundred and forty-two routinely processed breast tissue samples including normal breast, benign lesions, in situ and invasive carcinomas were investigated. E-cad and beta-cat were strongly expressed by luminal and basal cells in normal glands, benign proliferative and early neoplastic intraductal lesions. Contrarily, CD44 was expressed exclusively by myoepithelial cells in normal breast, whereas different isoform expression patterns were observed in premalignant and malignant lesions. Simultaneous lack of E-cad/beta-cat expression was detected in in situ and invasive lobular carcinomas in contrast to ductal lesions, in which the differential loss of the molecules was associated with poorer differentiation, irrespective of CD44 immunophenotype. Reduced E-cad (P = 0.003), beta-cat (P = 0.03) and increased CD44v4 (P = 0.005) and v7 (P = 0.007) expression were significantly associated with positive lymph node status. Decreased E-cad and lack of CD44v6 expression correlated with poor survival. There was no difference between the expression of either molecule in in situ and invasive components within the same tumour.

CONCLUSIONS

Our results indicate that changes in E-cad, beta-cat and CD44 expression occur early in breast carcinogenesis; they are involved in tumour differentiation, but events additional to their deranged expression are needed to acquire an invasive phenotype.

E-cadherin and catenins: molecules with versatile roles in normal and neoplastic epithelial cell biology

E-cadherin and its associated cytoplasmic proteins alpha-, beta-, and gamma-catenin, play a crucial role in epithelial cell-cell adhesion and in the maintenance of tissue architecture. Perturbation in the expression or function of any of these molecules results in loss of intercellular adhesion, with possible consequent cell transformation and tumour progression. The catenins are connected to many structural and functional proteins, which in turn influence their functions. Among these molecules are type 1 growth factor receptors, which along with other molecules are believed to alter the function of catenins through tyrosine phosphorylation. A recent finding is the association between the catenins and the adenomatous polyposis coli gene product (APC). APC mutation is an early event in colorectal carcinogenesis. It may possibly do so through perturbation of the critical cadherin/catenin complex. Further studies of the cadherin/catenin complex and its connections may give insight into the early molecular interactions critical to the initiation and progression oftumours, which should aid in the development of novel therapeutic strategies for both prevention and treatment.

E-cadherin and calretinin: a useful combination of immunochemical markers for differentiation between mesothelioma and metastatic adenocarcinoma

AIMS

To assess the diagnostic accuracy of combinations of antibodies in the differential diagnosis of metastatic carcinomas and mesotheliomas in pleural lesions.

METHODS AND RESULTS

The specificity and sensitivity of the commercially available antibodies Ber-EP4, MOC-31, CEA, B72.3, CD15, E-cadherin and calretinin were evaluated using an indirect immunoperoxidase staining technique. This technique was applied to formalin-fixed, paraffin-embedded tissue blocks of pleural lesions. Twenty-one patients with metastatic carcinoma (MC) and 20 patients with malignant mesothelioma (MM) were included. The combination E-cadherin/calretinin had the highest specificity (MC 100% and MM 91%) and sensitivity (MM 100% and MC 91%) considering both categories of tumours.

CONCLUSIONS

The combination of E-cadherin/calretinin appears to be a suitable panel for distinguishing metastatic carcinomas and mesotheliomas in pleural lesions. The additional value of other markers is limited.

Management strategies for colorectal liver metastases--Part I

Colorectal cancer is a common malignancy and the incidence of this disease is increasing. Approximately 50% of patients with colorectal cancer die from recurrent disease following an apparently curative resection of the primary tumour and the liver is the most frequent site of relapse. Although only a small proportion of patients will benefit from resection of liver metastases, this form of treatment offers the only possibility of cure. In selected patients, 5-year survival rates of 25-35% may be achieved following liver resection. A poor prognosis after resection of hepatic metastases is likely when there are more than three metastatic deposits, involved resection margins often as a result of ¿wedge' resections, when there is extrahepatic disease, or when there is nodal involvement at the primary tumour site. Regional hepatic artery infusion chemotherapy may provide palliation and possibly even prolongation of survival for some patients with unresectable metastases. Cytoreductive techniques may also provide palliation in selected patients with hepatic metastases unsuitable for resection; cryotherapy is the most promising of these methods.

Prognostic significance of E-cadherin expression in human colorectal cancer tissue

The expression of E-cadherin was determined by immunohistochemical staining in tumor tissue and in adjacent normal mucosae taken from 100 resected specimens of colorectal carcinomas. The expression of E-cadherin was preserved in all normal mucosae, but in the tumor tissue specimens it was preserved in 43, heterogeneous in 32, and lost in 25 samples. The lost or heterogeneous expression of E-cadherin correlated closely to the following: an advanced clinical stage of colorectal cancer, advanced tumor penetration, undifferentiated tumor histology, widespread lymph node involvement, liver metastasis, and permeation into the lymphatic and venous channels. The lost or heterogeneous expression of E-cadherin in tumor tissue was also significantly associated with an increased incidence of tumor recurrence after apparently curative resection, a reduced overall survival rate, and a reduced disease-free patient survival rate. A multivariate analysis disclosed that the expression of E-cadherin in tumor tissue was a significant prognostic variable independent of other clinicopathological features.

E-cadherin expression in upper-urinary-tract carcinoma

Carcinoma of the upper urinary tract is a relatively rare neoplasm, and few studies have dealt with clinicopathological findings and prognosis in a large number of cases. The purpose of our investigation was to look for a possible relation between E-cadherin (E-CD) immunoreactivity and clinicopathologic findings or clinical outcome in transitional-cell carcinoma of the upper urinary tract (TCC-UUT). To this end, we investigated E-CD immunoreactivity in 154 cases of TCC-UUT. E-CD immunoreactivity was recognized as being of "normal" pattern in 29.2% of samples. The relationship between E-CD immunoreactivity and clinicopathologic findings was significant for stage, grade and pattern of growth. The 5-year disease-free rate for 147 cases and 5-year overall survival rate for 154 cases were 55.7% and 71.5%, respectively. A univariate analysis of survival revealed that stage, grade, pattern of growth and E-CD immunoreactivity all had a significant effect on disease-free and overall survival rates. In the final models of multivariate analysis, however, we found that, for disease-free survival and for overall survival, only stage was a factor for progression or prognosis. Detection of E-CD immunoreactivity appears to be of limited value in deciding the prognosis of TCC-UUT.

E-cadherin expression in human epithelial ovarian cancer and normal ovary

The ovarian surface epithelium (OSE) is the origin of the majority of human ovarian cancers. These adenocarcinomas are characterized by initial local growth followed by spreading into the peritoneal cavity at later stages of tumor progression. The cell-adhesion molecule E-cadherin (E-cad) plays an important role in maintaining tissue integrity. Disappearance or impaired function of E-cad have often been associated with tumor formation and invasion in vivo and in vitro. The cell-specific expression of E-cad was investigated in normal human ovaries (n = 12), in benign (n = 5) and borderline (n = 4) ovarian epithelial tumors and in adenocarcinomas of different stages and histological grades (n = 18), by immunohistochemistry and immunoblotting. An ovarian cancer cell line (NIH-OVCAR3) was used as a reference. The epithelial origin of the cells was confirmed with cytokeratin (AE1/AE3) staining. In normal ovaries, the expression of E-cad was limited to inclusion cysts or deep clefts lined with OSE, whereas no staining of the OSE could be demonstrated at the surface of the ovary. In contrast, benign and borderline tumors uniformly expressed E-cad. This was observed in malignant tumors of all stages despite their degree of differentiation. E-cad was also present in metastasis from such tumors. The cell-specific expression of E-cad in inclusion cysts of normal ovaries and in epithelial layers of borderline tumors indicates a role for E-cad in the early events of the progression to a malignant phenotype. E-cad was not downregulated in later stages of ovarian cancer progression.

Differential expression of N-cadherin in pleural mesotheliomas and E-cadherin in lung adenocarcinomas in formalin-fixed, paraffin-embedded tissues

The differential diagnosis of pleural mesotheliomas and lung adenocarcinomas presents a continued challenge in the practice of surgical pathology. Paraffin immunohistochemistry (IHC) using different panels of antibodies can be helpful in some cases, but, as yet, no antigen is expressed specifically in mesotheliomas nor in adenocarcinomas. Using well characterized monoclonal antibodies (MAb) that recognized distinct mesenchymal and epithelial adhesion proteins, N-cadherin (13A9 MAb) and E-cadherin (E9 MAb), respectively, we found previously that in frozen-section IHC mesotheliomas and adenocarcinomas had distinct cadherin phenotypes: mesotheliomas were positive for N-cadherin, and lung adenocarcinomas were positive for E-cadherin. Using antigen-retrieval methods, we successfully extended our study to formalin-fixed, paraffin-embedded tissue sections. Tumors from 28 patients (14 originally diagnosed as mesotheliomas, and 14 diagnosed as adenocarcinomas) were stained with 13A9 MAb and E9 MAb. Review of hematoxylin-eosin sections excluded from analysis one case previously diagnosed as mesothelioma, which represented a hemangiopericytoma. Of the remaining 27 cases, 12 of 13 mesotheliomas were positive for N-cadherin and negative for E-cadherin. The exception was a multifocal microscopic papillary tumor of apparent mesothelial origin, which was negative for both N-cadherin and E-cadherin. Conversely, 13 of 14 adenocarcinomas were E-cadherin positive and N-cadherin negative except for one adenocarcinoma with focal N-cadherin expression. One case of a poorly differentiated adenocarcinoma invading skeletal muscle was negative for both 13A9 and E9. These studies confirmed the utility of the cadherin antibodies in distinguishing pleural mesotheliomas from lung adenocarcinomas. The reactivity of the cadherin-specific antibodies with antigens in paraffin sections make them powerful and reliable markers in the practice of diagnostic surgical pathology.