Value of ultrasound in preoperative local staging in early breast cancer

PURPOSE

The purpose of this study was to determine the precision of breast ultrasound for the measurement of breast lesions compared to the histological measurement. A number of other dependent variables were also analyzed.

MATERIAL AND METHODS

460 patients with 445 malignant lesions were examined using breast ultrasound and the lesions were measured and compared to the histologically measured size. The data was further analyzed according to histology, tumor stage, age, grading and therapy.

RESULTS

Metric comparison showed good correlation between sonography and the pathologically measured size of breast lesions, especially in tumor stage T 1 and T 2 and within ductal invasive carcinomas. Higher tumor stages lead to imprecise measurements and the histological type of lobular invasive carcinoma also results in imprecise measurements. Age and grading do not influence measurement precision.

CONCLUSION

Breast ultrasound allows precise measurement of breast lesions especially at lower tumor stages. The higher the tumor stage, the more imprecise the measurement becomes. Multivariate analysis shows no cross impact between tumor stage and histological type with respect to the quality of measurement.

Guideline-conform systemic treatment improves survival of breast cancer patients

Abstract #2115

Purpose: The influence of guidelines for systemic therapy of early-stage breast cancer on survival of patients is still not clear. We investigated to which extend adherence to the St Gallen expert consensus recommendations can improve outcome of the disease.
 Methods: Clinical characteristics and survival data of 2454 patients with early breast cancer which received primary therapy between 1992 and 2005 at a cancer referral center were collected by patient chart review, queries to local death registries and physicians involved in follow-up care. Patients were assigned one of three risk categories and an algorithm based on the St Gallen Expert Consensus 2005 on primary therapy of early-stage breast cancer was developed to estimate risk reduction by compliance to consensus recommendations using different Cox proportional hazard models.
 Results: According to the St Gallen consensus recommendations, indication for endocrine therapy was classified as mandatory in 78.3% (n=1922) of patients and as optional in 3.7% (n=92). A significant risk reduction by guideline-compliant endocrine therapy in patients with mandatory indication (HR = 0.62, CI 0.48 - 0.81) and also in patients with optional indication for endocrine therapy (HR = 0.20, CI 0.04 - 0.90) was estimated after adjustment for prognostic factors, co-existing morbidity and adjuvant treatment measures. Based on the consensus, indication for chemotherapy was classified as mandatory in 42.5% (n=1044) of the patients and as optional in 53.7% (n=1318). A significant risk reduction was observed for both subgroups of patients after adjustment for prognostic factors, co-existing morbidity and adjuvant treatment measures (HR = 0.80, CI 0.59 - 1.09 and HR = 0.53, CI 0.33 - 0.86). Model based estimates of overall survival for the subgroup of patients for whom endocrine therapy is mandatory and chemotherapy is optional is shown in figure 1, even more pronounced effects were found in patients for whom both endocrine therapy and chemotherapy are mandatory.
 
 
 
 Conclusion: Systemic adjuvant therapy in accordance with the St Gallen consensus recommendations 2005 is clearly associated with prolonged survival. Chemotherapy and endocrine therapy are beneficial when applied in accordance with the indications of St. Gallen consensus recommendations.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2115.

Predicting nonsentinel node status in breast cancer preoperatively by molecular characterization of core needle biopsies with multiparametric protein analyses

21068

Background: Axillary lymph node dissection (ALND) still remains the standard treatment for breast cancer patients with sentinel lymph node (SLN) metastases. However, since only 40% to 60% of patients show additional lymph involvement, complete ALND offers no additional benefit for almost 50% of patients but carries a significant risk of axillary morbidity. In an attempt to achieve a more precise prediction for the individual patient a multivariable logistic-regression analysis of a large data set of eight histopathological variables has been published by the Memorial Sloan-Kettering Cancer Center (MSKCC) that predicts the likelihood of metastases in Non-SLNs with a ROC of 0,71. To achieve a more precise estimation of additional lymph node involvement preoperatively we analysed molecular markers of potential predictive value. Methods: Beside histopathological variables, fifty proteins of potential prognostic and predictive value were preoperatively quantified in lysates from 120 core needle biopsies with multiplex sandwich immunoassays. Biopsies, taken at the Breast Cancer Center of the University of Ulm Medical School, were classified as invasive mammary carcinomas. Variables which could be used to improve the accuracy of prediction of non-sentinel lymph node (NSLN) involvement were defined. Results: We demonstrated appropriate sensitivity, reproducibility, and robustness for this protein microarray technology to characterize proteins in core needle biopsies and generate reliable data sets. In an initial univariate data analysis (Mann Whitney test) six of the analysed parameters (TIMP2, p= 0,027; FasR, p = 0,0025; MIF, p= 0,030; FGF-2, p= 0,0020, PDGF AA/BB p= 0,027; RANTES p= 0,024) correlated with NSLN involvement beside known histopathological variables (i.e. tumor size, p= 0,006; grading, p = 0,0009). Conclusions: We defined molecular markers of diagnostic value to predict NSLN involvement. This might be an acceptable substitute to the known histopathological variables by the MSKCC nomogram to predict potential NSLN involvement preoperatively.

No significant financial relationships to disclose.

Protein multiplex sandwich immunoassay: A reliable and objective method for complete molecular characterization of breast cancer from core needle biopsies

20025

Background: Within the last years, protein microarrays have been developed to quantify a large number of parameters present in a given sample simultaneously. Such miniaturised and parallelised sandwich immunoassays are of general interest for all proteomic and diagnostic approaches in which several parameters have to be determined from small samples. We describe the development of a bead-based flow cytometry that represents a convenient approach for rapid multiplex detection of functional target molecules from breast cancer biopsies. Methods: Briefly, sonographically guided core needle biopsies (CNB) were performed from 120 breast cancer masses from different patients. All biopsies were carried out with an automated core biopsy device fitted with 14-gauge (22 mm excursion) needles. Tumor samples were frozen on at −70 Celsius and pulverized. Proteins were extracted, allowing the simultaneous quantification of more than hundred proteins by a bead-based multiplex sandwich immunoassay. Results: The total amount of extracted protein from tumor tissues (mean weight of 20 mg) ranged from 300 to 1000 μg. We demonstrate appropriate sensitivity, reproducibility, and robustness for this protein microarray technology to characterize clinical samples and generate reliable data sets. A set of multiplexed sandwich immunoassays based on Luminex beads were developed that identify marker proteins indicative of prognosis or response to therapeutic options. Up to almost hundred parameters were identified and quantified simultaneously of which estrogen, progesterone and HER2 status in the multiplex assay was highly significant correlated to results obtained by immunohistochemistry (IHC) (p < 0.01). Conclusions: Our results demonstrate that this new bead-based protein microarray technology rapidly and reliably characterizes tissue samples to generate data sets of molecular marker. Therefore, this technology may once replace traditional IHC in determining marker proteins indicative of prognosis or response to therapeutic options.

No significant financial relationships to disclose.

Ultrasound-guided large-core needle biopsies of breast lesions: analysis of 962 cases to determine the number of samples for reliable tumour classification

The objective of this one-institutional study was to determine the number of large-core needle biopsies (LCNB), under three-dimensional ultrasound (3D-US) validation, that are sufficient to obtain a reliable histological diagnosis of a sonographically detectable breast lesion. Over an 28-month period, 962 sonographically guided LCNB were performed under 3D-US validation to assess 962 breast lesions. All biopsies were carried out with an automated core biopsy device fitted with 14-gauge (22 mm excursion) needles. Data of 962 biopsied breast lesions were gathered. Surgical follow-up was available for 659 lesions. Breast malignancies were diagnosed by ultrasound-guided LCNB with a sensitivity of 98.2% by performing three cores per lesion. In few cases, the open surgical specimen revealed the presence of invasive carcinomas in contrast to initial LNCB-based classification as ductal carcinomas in situ (DCIS, 11 lesions), lobular carcinoma in situ (one lesion), and atypical ductal hyperpasia (one lesion). Owing to disagreement between classification based on breast-imaging and histological findings, eight of these tumours were subsequently excised. Of the lesions that were removed at the patients’ requests despite benign LCNB diagnosis, two were infiltrating carcinoma and one a DCIS. We demonstrate that three 3D-US-guided percutaneous core specimens are sufficient to achieve tissue for a reliable histological assessment of sonographically detectable breast lesions and allow the detection of malignancies with high sensitivity and low rate of false-negative diagnoses.

Sentinel-node biopsy for axillary staging in breast cancer: results from a large prospective German multi-institutional trial

PURPOSE

To analyse the reliability of sentinel-node biopsy (SNB) in a multicentre setting and define conditions for the routine use of the procedure.

MATERIAL AND METHODS

SNB with consecutive axillary clearing was performed in 1124 breast cancer patients. The detection rate of a sentinel lymph node and its dependence on the choice of lymphography technique, patient selection, and technical procedure were analysed. The diagnostic performance of the sentinel-node method was compared to clinical, ultrasound-guided and histological staging. In order to study training effects all learning periods were included.

RESULTS

Twenty-two institutions with a total of 89 surgeons participated in the trial. The detection rate (overall: 85.2%) was found to be related to the applied lymphography technique, the experience of the institution and various technical factors of the procedure itself. The false-negative rate (FNR, overall: 8.2%) was independent of patient selection and technical features. The FNR did not depend on experience in the application of the method, but seemed related to surgical accuracy to detect sentinel nodes. Compared to conventional staging procedures (palpation, ultrasound) SNB yielded highly reproducible results for the prediction of the axillary status even in a multicentre setting involving surgeons with different training status.

CONCLUSION

SNB is suited as standard of care procedure. Measures of quality control appear more important than learning periods to minimize the FNR.

Endoscopic axillary surgery in breast cancer

Background

The aim was to provide an assessment of the current status of endoscopic axillary surgery in patients with breast cancer.

Methods

Fifty-three patients underwent endoscopic lymphadenectomy. The surgical efficiency (operating time, number of resected nodes, intraoperative and postoperative complications), short-term morbidity (duration of drainage, total lymph flow, seroma rate) and long-term outcome (pain, numbness, mobility, strength, oedema) were assessed. The incidence and severity of different arm symptoms were compared with the results of 396 patients treated with a conventional axillary procedure. Finally, all available data relating to endoscopic axillary surgery were reviewed.

Results

The operating time ranged from 60 to 150 min. A mean 17 (range 10–28) lymph nodes was resected. The extent of postoperative lymphorrhoea (mean 372 ml) and the seroma rate (eight of 34 patients) were not significantly reduced in comparison with conventional surgery. The assessment of long-term morbidity revealed fewer disturbances of sensitivity and a decreased rate of severe symptom intensity for pain, oedema and complaints related to mobility.

Conclusion

Despite excellent visualization of anatomical landmarks and improved long-term morbidity, endoscopic lymph node dissection cannot be regarded as a suitable technique for routine axillary management in breast cancer because of long operating times.

Unusual neck mass in an adolescent: benign basal cell adenoma of the minor salivary glands of the piriform sinus

With an incidence of less than 3%, salivary gland tumors are rare in the head and neck. The percentage of basal cell adenomas within the group of salivary gland tumors is even less (0.2-2%). Salivary gland tumors occur very rarely in adolescents. The basal cell adenoma commonly affects older persons and occurs most frequently in the major salivary glands. We present the unusual case of a benign basal cell adenoma of the minor salivary glands of the piriform sinus in a 14 year old male patient. Unusual are the age of the patient, the histological type, size and localisation of the tumor.

Fluorine-18 2-deoxy-2-fluoro-D-glucose PET in the preoperative staging of breast cancer: comparison with the standard staging procedures

The present study compared the diagnostic accuracy of fluorine-18 2-deoxy-2-fluoro-D-glucose positron emission tomography (FDG-PET) with conventional staging techniques. The differentiation between malignant and benign lesions and the detection of multifocal disease, axillary and internal lymph node involvement, and distant metastases were evaluated. One hundred and seventeen female patients were prospectively examined using FDG-PET and conventional staging methods such as chest X-ray, ultrasonography of the breast and liver, mammography and bone scintigraphy. All patients were examined on a modern full-ring PET scanner. Histopathological analysis of resected specimens was employed as the reference method. The readers of FDG-PET were blinded to the results of the other imaging methods and to the site of the breast tumour. The sensitivity and specificity of FDG-PET in detecting malignant breast lesions were 93% and 75% respectively. FDG-PET was twofold more sensitive (sensitivity 63%, specificity 95%) in detecting multifocal lesions than the combination of mammography and ultrasonography (sensitivity 32%, specificity 93%). Sensitivity and specificity of FDG-PET in detecting axillary lymph node metastases were 79% and 92% (41% and 96% for clinical evaluation). FDG-PET correctly indicated distant metastases in seven patients. False-positive or false-negative findings were not encountered with FDG-PET. Chest X-ray was false-negative in three of five patients with lung metastases. Bone scintigraphy was false-positive in four patients. Three patients were upstaged since FDG-PET detected distant metastases missed with the standard staging procedure. It is concluded that, compared with the imaging methods currently employed for initial staging, FDG-PET is as accurate in interpreting the primary tumour and more accurate in screening for lymph node metastases and distant metastases. Due to a false-negative rate of 20% in detecting axillary lymph node metastases, FDG-PET cannot replace histological evaluation of axillary status.

Axilloscopy and endoscopic sentinel node detection in breast cancer patients

BACKGROUND

Sentinel node biopsy is a promising technique that allows the axillary status of breast cancer patients to be predicted with high accuracy. Reducing false negative results remains a major challenge for the improvement of this procedure. Furthermore, new techniques are required to achieve axillary clearing with less morbidity in cases of unsuccessful mapping or multicentric carcinoma. We analyzed whether axilloscopy and endoscopic sentinel node biopsy is a feasible procedure for visualization of the axillary space and resection of the sentinel node using endoscopic techniques.

METHODS

Following blue dye-guided lymphography and liposuction of the axillary fat, endoscopic axillary sentinel node biopsy was performed in 35 breast cancer patients. We then assessed the exposure of anatomical landmarks, the detection rate of the sentinel node, the false negative rate, and the accuracy of consecutive axillary clearing.

RESULTS

In almost every case, an excellent anatomical orientation was achieved. The detection rate for the sentinel node was 83.3%. In one case, the sentinel node did not reflect the status of the residual axilla. A mean number of 17.1 lymph nodes was harvested at consecutive axillary clearing.

CONCLUSIONS

Axilloscopy and endoscopic sentinel node biopsy, following liposuction of the axillary fat, is a feasible procedure that allows identification and minimally invasive resection of the sentinel node with high accuracy. The endoscopic approach might help to minimize the pitfalls of sentinel node biopsy by visualizing the axillary space. In future, it may become a technique that enables minimally invasive axillary clearing when complete lymphadenectomy is required.

[Endoscopic axillary lymph node excision--results of a pilot study]

OBJECTIVE

Assessment of axillary nodal status with reduced shoulder-arm-morbidity remains a major challenge for primary surgery of breast cancer patients. In a pilot study endoscopic axillary lymph node dissection was evaluated.

MATERIAL AND METHODS

In 30 breast cancer patients axillary lymphadenectomy was performed after liposuction using an endoscopic approach. During a learning phase of 15 cases an open revision was routinely carried out. Later complete endoscopic lymph node dissection was performed. The exposition of anatomical landmarks, the number of resected lymph nodes, postoperative lymphorrhea, histopathological signs of traumatisation were assessed as well as intra and postoperative complications.

RESULTS

In any case we found excellent exposure of anatomical landmarks. Following a learning curve of 15 cases the average number of resected lymph nodes was equal to the average number of lymph nodes resected with conventional techniques (18.2 vs. 18.4, median 17 vs 18). Minimal intraoperative complications were observed. Postoperative lymphorrhea and seroma rate were not remarkably reduced in comparison with open procedures.

CONCLUSIONS

Our study demonstrates, that endoscopic lymph node dissection may be performed with a low complication rate and with identical accuracy as achieved by open techniques.

CD95 (APO-1/Fas)-mediated apoptosis in colon epithelial cells: a possible role in ulcerative colitis

BACKGROUND & AIMS

Ligation of CD95 (APO-1/Fas) by antibody or CD95 ligand (CD95L) induces apoptosis and, in some cell lines, growth. Normal colonic epithelial cells constitutively express CD95. The function of CD95 on colonocytes is unknown. The aim of this study was to elucidate the role of epithelial CD95 in the normal colon and in ulcerative colitis.

METHODS

Intact colonic crypts were isolated, and the effects of CD95 ligation in vitro were studied. CD95L-expressing cells and apoptotic cells were detected in situ by RNA hybridization, immunohistochemistry, and DNA nick end labeling.

RESULTS

On CD95 ligation, isolated colonic crypt cells underwent apoptosis within 4 hours. No growth-promoting effect was observed. In normal colon, CD95L expression was restricted to few mononuclear cells randomly scattered within the lamina propria. Therefore, the CD95-CD95L system is very unlikely to operate in the regeneration of the colonic epithelium. However, in ulcerative colitis, the number of interstitial CD95L+ cells and the frequency of apoptosis in both lamina propria and epithelium were increased considerably. Further, a focal association of subepithelial CD95L+ mononuclear cells and epithelial apoptosis was observed.

CONCLUSIONS

In ulcerative colitis, soluble CD95L-mediated epithelial apoptosis may lead to a breakdown of the epithelial barrier function facilitating the invasion of pathogenic microorganisms.

Early detachment of colon carcinoma cells during CD95(APO-1/Fas)-mediated apoptosis. I. De-adhesion from hyaluronate by shedding of CD44

Ligation of CD95 (APO-1/Fas) cell surface receptors induces death in apoptosis-sensitive cells. Induction of apoptosis in adherent gamma interferon-stimulated HT-29 and COLO 205 colon carcinoma cells by cross-linking CD95 with anti-APO-1 monoclonal antibody resulted in detachment of the cells from hyaluronate starting about 1 h after antibody exposure. Loss of adhesion was paralleled by a substantial reduction of the multifunctional cell surface adhesion molecule CD44. As evidenced by cycloheximide treatment, this effect was not caused by impaired protein synthesis. Depletion of surface CD44 was also not due to membrane blebbing, since cytochalasin B failed to inhibit ascension from hyaluronate. Instead, ELISA and time kinetics showed increasing amounts of soluble CD44 in the supernatant of CD95-triggered cells. SDS-PAGE revealed that soluble CD44 had an apparent molecular mass of about 20 kD less than CD44 immunoprecipitated from intact cells. Thus, CD95-triggering induced shedding of CD44. Shedding is a novel mechanism operative in early steps of CD95-mediated apoptosis. Shedding surface molecules like CD44 might contribute to the active disintegration of dying epithelial cells in vivo.

Rapid onset of apoptosis in vitro follows disruption of beta 1-integrin/matrix interactions in human colonic crypt cells

BACKGROUND & AIMS

Apoptosis by loss of adherence is a recently described phenomenon termed "anoikis." beta 1, integrins are heterodimeric surface molecules mediating adhesion to the extracellular matrix. The aim of this study was to address whether anoikis accounts for the elimination of senescent enterocytes and, if so, whether beta 1 integrins are involved.

METHODS

Whole crypts were isolated from normal human colonic mucosa and examined in vitro.

RESULTS

The vast majority of cells in resuspended crypts rapidly underwent apoptosis within 4 hours. Apoptosis was partially inhibited when cells had contact with collagen I-coated membranes or when whole crypts were embedded in a collagen gel. Preincubation of crypts with an inhibiting anti-beta 1 antibody before readhesion caused a much higher apoptotic rate. Confocal microscopy of embedded crypts revealed two critical zones of high sensitivity to temporary loss of adherence: the base of the crypts where stem cells are supposed to reside and the crypt mouth including the surface epithelium.

CONCLUSIONS

Survival of colonic epithelia crucially depends on matrix adhesion and is likely to be guaranteed by beta 1-integrin/ matrix interaction. The data strongly suggest that anoikis is the way senescent colon cells die.

In situ detection of enterocytic apoptosis in normal colonic mucosa and in familial adenomatous polyposis

Physiological regeneration of colonic epithelium entails proliferation at the crypt base and cell loss by shedding or cell death. The aim of this study was to localise and assess the rate of apoptosis in normal and neoplastic colonic epithelium with respect to zones of proliferation. Familial adenomatous polyposis (FAP) was chosen as a model to study neoplastic transformation of colonic mucosa at an early stage. Apoptotic cells were detected in situ by TdT-mediated biotin-dUTP nick end labelling (TUNEL) in parallel to cells in cycle determined by Ki-67 immunohistochemistry using the monoclonal antibody MiB-1. By detection of genomic fragmentation, two different patterns of enterocytic apoptosis emerged: (a) apoptotic bodies being engulfed by adjacent epithelial cells, and (b) apoptotic cells with only subtle morphological changes being extruded into the gut lumen. The engulfment pattern was seen predominantly in the crypts of the normal colonic mucosa and, although very rare, was clearly confined to the basal proliferation compartment. The extrusion pattern was restricted to the luminal mucosal surface. Adenomas of FAP showed highly increased numbers of apoptotic bodies, which were scattered throughout the transformed mucosa. Both patterns of apoptosis were topographically intermingled although the extrusion pattern prevailed at the luminal adenoma surfaces. Whereas cells in cycle were somewhat more numerous in the upper parts of the crypts, apoptosis occurred with increased frequency at sites beneath the proliferation maximum suggesting an inverted direction of epithelial cell migration in adenomas. These results suggest two distinct routes towards enterocytic apoptosis in the colonic mucosa leading to engulfment or extrusion of dying cells. Adenomatous transformation of colon epithelium is associated with a considerable increase of the cellular turnover rate and with a severe disturbance of the microtopographical localisation of birth and death of enterocytes.

Differential expression of the microspike-associated protein moesin in human tissues

The protein moesin is a member of a gene family consisting of talin, ezrin, radixin, protein 4.1., and merlin. Proteins of this family are associated to the submenbranous cytoskeleton. Using monoclonal antibody 38/87 directed against moesin in immunochemical analysis, the 78 kDa moesin protein was demonstrated in endothelial cells and in cells of carcinoma, mesothelioma and lymphoid origin. Moesin was metabolically labeled by [32P]orthophosphate and reacted with an antibody against phosphotyrosine. Moesin also contains carbohydrate residues as demonstrated by immunostainings of digoxigenin-labeled sugar residues. The antibody 38/87 in comparison to antisera against radixin and ezrin was applied in immunohistological stainings on various human tissues. As a prominent feature, moesin as strongly expressed in endothelium of vessels in contrast to radixin and ezrin. Moesin but not radixin was observed in T and B lymphocytes. Further, moesin was expressed in basal layers of squamous epithelium and glandular ducts and lymphocytes. Subcellular expression of moesin was studied on cultured human endothelial cells of umbilical cord veins and the mesothelioma cell line CH3LC by confocal laser scanning microscopy. In subconfluently growing cells moesin showed a characteristic expression on extending microspikes at the basal cell level. Moesin was coexpressed with actin in the cortical cytoskeleton and on microspikes but not in stress fibers. The differential cellular expression of moesin and its pronounced occurrence on microspikes of growing cells support the possibility that moesin is a protein involved in plasma membrane-cytoskeleton interactions in specialized tissues.

The capacity of human malignant B-lymphocytes to disseminate in SCID mice is correlated with functional expression of the fibronectin receptor alpha 5 beta 1 (CD49e/CD29)

The alpha 5 beta 1 integrin (CD49e/CD29), a heterodimeric membrane protein, is the "classical" fibronectin receptor on many cell types. During B-cell ontogeny, expression of the alpha 5-subunit is developmentally regulated. The alpha 5 beta 1 is decisive for migration on fibronectin substrate and very likely cooperates with other adhesion molecules in transvascular trafficking. To test whether alpha 5 beta 1 influences local growth vs. disseminative spread of neoplastic B-cells in vivo, human B-cell lines mimicking different maturational stages were transferred s.c. into severe combined immunodeficiency (SCID) mice and examined for alpha 5 beta 1 expression and for adherence on fibronectin substrate in vitro and ex vivo. All cell lines were locally tumorigenic. Dissemination was observed in all animals carrying Nalm-6 tumors, in one animal with a BL 60 and in 2 mice carrying a Raji tumor. By contrast, Daudi, BJAB and U266 tumors did not disseminate. As evidenced by immunohistochemistry and flow cytometry, all lines and their tumors were to various extents beta 1-positive but showed considerable differences in alpha 5 expression. The functional surface expression of alpha 5 beta 1 correlated with fibronectin adherence of the lines. Daudi expressed alpha 5 beta 1 in a non-functional configuration which was rendered functional only upon applying high concentrations of Mg++ and Mn++. B-cell lines functionally expressing alpha 5 beta 1 at high or moderate levels disseminated in SCID mice while alpha 5-negative lines and Daudi did not. These results support the conclusion drawn from an earlier in situ analysis of human B-cell lymphomas/leukemias that the alpha 5 beta 1 integrin contributes to the disseminative phenotype of malignant B cells.

Fibronectin and fibronectin-receptors of the integrin type in normal colon mucosa, adenoma and carcinoma

Integrin alpha 3, alpha 4, alpha 5, and alpha v subunits heterodimerize with beta 1 and beta 3 chains to form functional fibronectin (FN) receptors. Two of them, alpha 4 beta 1 and alpha 5 beta 1, recognize FN as the only matrix molecule. Additional binding of laminin, collagen, and entactin is achieved by alpha 3 beta 1 while alpha v beta 1 and alpha v beta 3 also bind vitronectin. We investigated immunohistochemically the tissue distribution of FN and the expression of FN receptor alpha- and beta-chains in 20 normal colon tissues, 10 adenomas, 90 carcinomas, and 10 liver metastases derived thereof. In normal and adenomatous colon tissues FN was detected in association with reticular and fibrillar structures of the gut wall. The tumor stroma of carcinomas and liver metastases contained abnormally high amounts of FN which were detectable as chaotic deposits. Normal and adenomatous mucosa were alpha 3(+), alpha 4(-), alpha 5(-), alpha v(+/-), beta 1(+), beta 3(-) indicating that only promiscuous FN receptors were expressed. 21 of 90 carcinomas had a focal or complete loss of alpha 3 which was more often found in Dukes C/D tumors (p<0.005). The liver metastases more often had lower levels of alpha 3 expression compared to the primary tumor. The alpha v-expression was inconsistent and often weak. These losses of FN receptor constituents in carcinomas were not paralleled by any noticeable differences in stromal content or distribution pattern of FN, Enhanced expression/induction of FN receptors was found in only 2 of 90 carcinomas which focally neo-expressed the alpha 5-chain. This aberrant alpha 5 expression, however, was flow cytometrically found in 3/4 colon carcinoma cell lines which otherwise had receptor profiles corresponding to the in situ situation. FN-adherence of cell lines was variable. Anti-alpha 3 had no blocking effect on FN adherence of SW480, SW620, and COLO 205 but a minor effect on FN binding of HT-29. Anti-alpha 5 blocked FN adhesion whenever alpha 5 was expressed. Anti-av had no blocking effect while anti-beta 1 reduced FN adherence of all cell lines. The net biological effect(s) of aberrant expression of integrin type FN receptors in colon carcinomas is unpredictable as yet.

Comparative evaluation of integrin alpha- and beta-chain expression in colorectal carcinoma cell lines and in their tumours of origin

The integrin family consists of broadly expressed cell surface adhesion receptors, each member of which is composed of a non-covalently linked alpha/beta heterodimer. Integrin receptors are involved in the interaction with matrix proteins and may contribute to invasion and metastasis of carcinomas. To examine the biological role integrins play in colorectal carcinoma we compared the expression of integrin alpha- and beta-subunits in situ and in vitro. Eight newly established cell lines derived from immunohistochemically characterized colorectal carcinomas together with two sublines obtained after nude mouse passage and the commonly used colon carcinoma lines HT-29, SW480, SW620, and COLO 205 were investigated by immunocytochemistry and flow cytometry. The carcinomas in situ expressed alpha 1-, alpha 2-, alpha 3-, alpha 6-, alpha v- and beta 1-subunits in variable amounts while being devoid of alpha 4, alpha 5, and beta 3. The individual integrin profile of the tumour in tissue was essentially maintained in vitro. However, a neo expression of the alpha 5 chain was found, together with an induction or increase in alpha 1, alpha 2, alpha 3, alpha v and beta 1 levels. No decrease in integrin subunit expression was observed. Standard-serum and serum-free medium revealed no striking differences in alpha- and beta-chain expression in the cell lines HT-29 and COLO 205. In serum-free medium, SW480 showed a slight increase of alpha 1 and alpha 5 and a decrease of alpha 3 and alpha v while SW620 expressed more alpha 1. We conclude that the great variability of adhesion receptor expression of the integrin family in colorectal carcinomas in situ is essentially maintained in vitro, although culture conditions which are only marginally influenced by serum factors unpredictably lead to some increase in expression or even induction of several integrin subunits.

Expression of APO-1 (CD95), a member of the NGF/TNF receptor superfamily, in normal and neoplastic colon epithelium

APO-1 is a 48-kDa cell-membrane protein identical to the Fas antigen now designated CD95. It is a member of the NGF/TNF receptor superfamily. Anti-APO-1 monoclonal antibody induces apoptosis in a variety of cell types expressing this antigen. We immunohistochemically investigated APO-1 expression in normal colon mucosa, 20 adenomas, 258 colon carcinomas and 10 liver metastases and carried out in vitro studies using a panel of colon-carcinoma cell lines. Immunohistochemically, APO-1 was regularly expressed at the basolateral membrane of normal colon epithelia. In a minor fraction of colon adenomas and in 39.1% of colon carcinomas APO-1 expression was diminished and in 48.1% of carcinomas, predominantly of the non-mucinous type, APO-1 expression was completely abrogated. The normal level of APO-1 in carcinomas was correlated with the mucinous type. Reduced/lost APO-1 expression was more frequent in rectal carcinomas. Complete loss of APO-1 was more frequent in tumors that had already metastasized. APO-1 expression in liver metastases essentially corresponded to that of the primary tumors. Comparative analysis with data from previous studies revealed that the mode of APO-1 expression is correlated with that of HLA-A,B,C./beta 2m, HLA-DR, HLA-D-associated invariant chain and of the secretory component. Surface expression of APO-1 was heterogeneous in colon-carcinoma cell lines; SW480 expressed considerable amounts of APO-1 on all cells, while HT-29 constitutively did less so and only in a minority of cells. Surface density of APO-1 and the fraction of positive cells in HT-29 was enhanced by interferon-gamma (IFN-gamma) and, additively, by tumor necrosis factor-alpha (TNF-alpha), whereas in SW480 APO-1 expression was not modulated by these cytokines. We conclude that neoplastic transformation of colon epithelium often leads to a loss of the physiologic, high level of surface APO-1 by giving rise either to a stable lack of APO-1 or to an IFN-gamma/TNF-alpha-sensitive phenotype of inducible APO-1 expression.

Evaluation of the secretory component as a prognostic variable in colorectal carcinoma

Expression of the secretory component (SC) of IgA was investigated in normal colonic mucosa, in adenomas and in 188 colon carcinomas. Of the carcinoma patients, 149 underwent potentially curative surgical treatment. In particular, it was of interest to determine whether pathohistological or clinical parameters showed any association with the mode of SC expression in carcinomas. Irrespective of anatomical site, normal colon mucosa was generally SC-positive. Normal epithelium, however, displayed microheterogeneity in SC content, which was related to columnar and goblet-cell type and microtopographical site, implying a subtle regulatory mechanism. In contrast to adenomas, which were evenly SC-positive and showed focally weak SC expression in only 2 out of 20 cases, carcinomas were rather heterogeneous in their SC-expression pattern. In all, 48 carcinomas were entirely positive, 48 were completely negative and the remaining 92 showed various patterns of heterogeneous SC expression. The mode of SC expression was correlated with tumor staging, i.e., complete absence of SC was more often found in Dukes' C and D groups. In addition, the presence of SC in carcinomas was statistically correlated with the mucinous type. The mode of SC expression was not correlated with tumor grading and tumor location. The rate of disease-free survival and the risk of tumor-related death revealed a significant correlation with the mode of SC expression when patients who had received potentially curative or non-curative treatment were included in the log-rank test. Absence or low levels of SC expression were more frequent in the group that suffered a tumor relapse than in the recurrence-free cohort. Tumor-related death was more frequent when primaries were characterized by absence or low levels of SC expression. We conclude that absence or low levels of SC expression are an unfavorable prognostic variable in colorectal carcinoma.

Expression of CD59, a complement regulator protein and a second ligand of the CD2 molecule, and CD46 in normal and neoplastic colorectal epithelium

CD59 (protectin) and CD46 (membrane cofactor protein, MCP) are membrane-bound complement regulator proteins which inhibit complement-mediated cytolysis of autologous cells. CD59, a phosphatidyl-inositol-anchored glycoprotein, inhibits the formation of the terminal membrane attack complex (MAC) of complement and was found to be a second ligand for CD2 contributing to T-cell activation. In 20 colorectal normal mucosa samples, in ten adenomas, 71 carcinomas and in ten liver metastases derived thereof, CD59 was inconsistently expressed in the epithelial compartment. In carcinomas CD59 expression in the whole neoplastic compartment was more often found in well- and moderately differentiated tumours. By contrast, focal expression or even complete lack of CD59 was more often found in poorly differentiated tumours (P = 0.021). In addition, carcinomas without metastases at the time of operation (Dukes A/B) more often expressed CD59 in the entire neoplastic population compared to those carcinomas which had already metastasised (P = 0.018). There was no correlation between the mode of CD59 expression in colorectal carcinomas and the tumour type or location. CD46 has C3b/C4b binding and factor-I dependent cofactor activity and is broadly expressed in various cells and tissues. In the epithelial compartment of normal colorectal mucosa, of all adenomas, carcinomas and their liver metastases, CD46 was expressed throughout the epithelial compartment. Since CD46 was consistently expressed in colorectal carcinomas the low expression or even lack of CD59 in a subset of tumours might not lead to critical complement-mediated attack of CD59-negative tumour cells. Regarding CD59 as a natural T-cell ligand involved in cognate T-cell-target-cell interaction, however, loss of CD59 might well be a selection advantage, provided that tumour antigen-mediated T-cell toxicity in colorectal carcinoma exists.

Constitutive and induced expression of APO-1, a new member of the nerve growth factor/tumor necrosis factor receptor superfamily, in normal and neoplastic cells

BACKGROUND

APO-1 is a 48 kilodalton transmembrane, cysteine-rich glycoprotein identical with the Fas antigen which belongs to the nerve growth factor/tumor necrosis factor receptor superfamily. Cross-linking of APO-1 induces apoptotic cell death in sensitive cells.

EXPERIMENTAL DESIGN

As suggested by our preliminary results, APO-1 expression is not restricted to cells of the hematopoietic lineage. We therefore investigated APO-1 expression in normal human tissues and in various epithelial and nonepithelial tumors.

RESULTS

We show by immunohistochemistry that APO-1 is a non-lineage antigen constitutively expressed in a variety of epithelial cells. This includes the basal layers of various squamous epithelia, transitional epithelium and columnar epithelium of the biliary tract and intestine. Among the epithelial cell types of the reproductive system of both genders, APO-1 expression is complex. Except the satellite cells of autonomic ganglia, all cells of the nervous tissue are APO-1-negative. Among mesenchymal cells, constitutive APO-1 expression is rare but detectable in various kinds of activated cells, e.g. fibroblasts, osteoblasts, and subpopulations of endothelial cells. Within the immune system, APO-1 is broadly distributed among histiocytic cells but restricted to minor subpopulations of peripheral T and B cells. Immature T cells, i.e., thymocytes, do not express detectable APO-1-antigen. Expression of APO-1 was induced in phytohemagglutinin activated T cells and in a mammary carcinoma cell line by interferon-gamma alone and in combination with tumor necrosis factor alpha. Consistently, there was an in situ induction of APO-1 in several types of glandular epithelium in microtopographic association with lymphohistiocytic infiltrates. This inflammation-associated APO-1 induction went along with increased expression of this molecule within the lymphocytic compartment of the lesion. In tumors. APO-1 expression was heterogeneous. In comparison to their normal counterparts, some tumors showed abnormal hypo-expression or loss of APO-1. However, abnormal neo-expression was also found.

CONCLUSIONS

Tissue distribution, in vitro expression, and reaction upon cytokine-induced activation suggest that APO-1 might not only transmit apoptotic signals but might play a more general role in growth control.

Expression of beta 1 integrins in non-neoplastic mammary epithelium, fibroadenoma and carcinoma of the breast

beta 1 Integrins were examined immunohistochemically in normal and mastopathic mammary glands, 12 benign tumours and 90 carcinomas of the breast using monoclonal antibodies against beta 1 and alpha 1 to alpha 6 subunits. When compared with epithelial cells of non-neoplastic mammary glands and of benign tumours, carcinoma cells showed considerable quantitative changes in the pattern of alpha 2, alpha 3 and alpha 6 subunit expression. In contrast, the distribution pattern of beta 1, alpha 1, alpha 4 and alpha 5 antigens corresponded to the situation observed in non-neoplastic mammary gland epithelium in most instances. An abnormal expression of alpha 2 was found in 71.0% of the carcinomas ranging from a remarkably low number of alpha 2-positive tumour cells in 27.5% of the cases to a complete absence of the alpha 2 molecule in 43.5% of the carcinomas. Of the carcinomas 39.9% exhibited quantitative changes in alpha 3 expression with an abnormally low content of alpha 3-positive neoplastic cells in 15.4% and a complete absence of this molecule in 24.5% of the cases. Expression of alpha 6 was abnormal in 73.2% of the carcinomas, consisting in a greater number of alpha 6-negative tumour cells in 31.9% and in a complete absence of alpha 6 in 41.3% of the tumours. The abnormally low expression/absence of alpha 2 and alpha 3 subunits correlated with oestrogen receptor negativity (P < 0.033 and P < 0.04, respectively). In addition, abnormally low expression/absence of alpha 2 correlated with poor differentiation of the tumours (P < 0.014). The quantitative changes in the expression pattern of beta 1-associated alpha subunits in breast carcinomas may cause a disturbed cell-cell and/or cell-matrix interaction that increases the invasive and migratory property of the tumour cells.

Differential expression of annexins I and II in normal and malignant human mammary epithelial cells

Collagen-binding proteins (CBPs) of rat mammary tumors are identical to Ca(2+)-binding annexins. We have now isolated a protein of 38 kDa from the human mammary tumor cell line ALAB by collagen type I affinity chromatography as well as by extraction of calcium-binding proteins. The 38-kDa band of both preparations was identified as annexin II (calpactin I) by its reaction with an annexin II-specific monoclonal antibody in Western blot analysis. Annexin I (lipocortin I) was not detectable in these cells. Two other human cell lines, the SV40-transformed cell line SV3 and cell line HBL-100, both established from normal mammary glands, were also positive for annexin II and negative for annexin I. In vivo expression of annexins was investigated by immunohistological staining of normal and malignant human mammary tissue. The annexin II-specific mAb reacted with normal and tumor parenchyma whereas the annexin I-specific mAb reacted with acini and ductal myoepithelium of the normal mammary gland but showed no reaction with tumor tissue. Immunolocalization studies also showed annexin II expression in both normal and tumor stroma while only tumor stromal cells were found to be reactive with the antibody against annexin I. The differential expression of annexins in normal and malignant human mammary tissue suggests special functions of these proteins in the mammary gland.

Plasminogen activators and plasminogen activator inhibitors in human colorectal carcinoma tissues are not expressed by the tumour cells

Plasminogen activators (PA) have been implicated with the degradation of extracellular matrix during the invasive growth of metastasising tumour cells. The significance of PA expression in tumour cells for the in vivo growth of malignant tumours is still a matter of debate. We, therefore, performed immunohistological studies on human colon tumours using monoclonal antibodies against urokinase- (u-PA) and tissue-type plasminogen activator (t-PA) as well as against plasminogen activator inhibitors 1 and 2 (PAI-1, PAI-2). Normal colorectal mucosa of seven samples was negative for all four constituents of the PA system. Tumour epithelium of 64 colorectal carcinomas and 10 liver metastases was consistently negative for both, PA and their inhibitors. However, two of four human colon carcinoma cell lines weakly expressed u-PA, PAI-1 and PAI-2. Intestinal dendritic or fibroblast-like cells within the tumour tissue strongly expressed u-PA and, at a lower level, also t-PA, PAI-1 and PAI-2. Vascular endothelial cells were weakly positive for all components of the PA system in colon carcinoma. Our findings indicate that colon carcinoma cells in their natural environment do not express constituents of the PA system. PA activity, previously found in colon carcinoma tissue, is most likely derived from interstitial cells.

Decay-accelerating factor (DAF, CD55) in normal colorectal mucosa, adenomas and carcinomas

Decay-accelerating-factor (DAF, CD55), a phosphatidyl-inositol anchored glycoprotein, is a member of the cell membrane bound complement regulatory proteins that inhibit autologous complement cascade activation. DAF was found expressed on cells that are in close contact with serum complement proteins, but also on cells outside the vascular space and on tumour cells. Using CD55(BRIC110) and CD55(143-30) we show here that DAF(CD55) is only sporadically expressed on the luminal surface of normal colonic epithelium. However, 5/20 adenomas expressed DAF(CD55) on the cell surface of all tumour cells, 5/20 adenomas were completely negative, 10/20 adenomas expressed DAF(CD55) in various amounts. DAF(CD55) was expressed in various intensities on almost all tumour cells of the colon carcinoma cell line HT29. In 5/88 colorectal carcinomas DAF(CD55) was localised on the apical cell surface of all tumour cells, 31/88 were completely negative, 52/88 expressed DAF(CD55) in parts of their neoplastic populations. There was no correlation between the tumour grading, staging and location and the mode of DAF(CD55) expression, but DAF(CD55) was found more often in mucinous carcinomas (P = 0.007). Although the mode of DAF(CD55) expression is not correlated with tumour prognostic parameters, the upregulation of DAF(CD55) in a subset of adenomas and carcinomas needs further investigation concerning protection of tumour cells against complement cytotoxicity.

Adhesion receptor profile of thymic B-cell lymphoma

Primary thymic B-cell lymphoma is clinically characterized by aleukemic, highly aggressive local growth, infrequent distant metastasis, and infrequent secondary lymph node involvement. VLA-1 to VLA-6 are cell surface molecules binding to matrix molecules such as collagen, fibronectin, epiligrin, and laminin. VLA-4 additionally binds to VCAM-1 and ICAM-2, thus mediating intercellular adhesion. Other molecules involved in cell/cell adhesion are LFA-1 (CD11a/CD18), Mac-1(CD11b/CD18) and their ligand ICAM-1 (CD54), p150,95 (CD11c/CD18), LFA-3 (CD58), CD44, and LECAM-1. Twenty-three tumors, together with normal lymphoid tissue, were immunohistochemically examined to investigate the expression pattern of these molecules in thymic B-cell lymphomas and in their putative normal counterparts, namely thymic medullary B cells. Thymic B-cell lymphomas consistently lacked VLA-1,-2,-3,-5,-6, and CD11b, expressed ICAM-1 in 21 of 23 cases but were heterogenous for VLA-4, LFA-1, CD11c, LFA-3, CD44, and LECAM-1. Presence of LFA-1 correlated with LFA-3 expression (P = 0.029). The receptor profile of thymic B-cell lymphoma was reminiscent of the expressional status of normal thymic medullary B cells in some aspects but deviated in others: Assuming that, in terms of differentiation, thymic B-cell lymphoma is related to the asteroid variant of thymic medullary B cells, a propensity to down-regulate/lose VLA-4, CD11a, CD44, and LECAM-1 would have to be supposed in conjunction with a tendency to overexpress ICAM-1 and LFA-3. Sclerosis as an inconsistent phenomenon in thymic B-cell lymphoma was absent in 8 of 23 tumors. Presence of sclerosis correlated with LECAM-1 expression of the tumor cells (P = 0.038). Recent studies suggest that a locally growing/aleukemic phenotype of a B-cell neoplasia might be determined by the phenotype VLAs-, LFA-1+, ICAM-1+, CD44-, and LECAM-1-. Our data corroborate this view.

Altered content and distribution of tenascin in colitis, colon adenoma, and colorectal carcinoma

Tenascin is a fibroblast product and extracellular matrix protein probably excerting a fibronectin-antagonizing role. Tenascin is broadly distributed interstitially during embryogenesis but restricted to a small range of structures in normal adult tissues. Using tenascin antibodies and an indirect immunoperoxidase method, normal colon, colitis, colon adenomas, and colorectal carcinomas were examined for tissue distribution of tenascin. Normal mucosa displayed a sparce meshwork of microfibrillar tenascin in the lamina propria. The basement membrane was tenascin negative at the bottom of the crypt and developed into a positive band steadily broadening towards the mucosal surface. In colitis, this polarity was effaced; the basement membrane was a broad tenascin-positive band nearly throughout while interstitial tenascin was moderately increased. Loss of polarity in tenascin content of the basement membrane was a constant feature of adenomas, inconsistently paralleled by structural alterations in surface qualities and continuity of tenascin pattern of the basement membrane. These were most pronounced in carcinomas, where this interface was often discontinuous and had a rough surface; in addition, interstitial tenascin was considerably increased. In carcinomas, the rough surface aspect of the tenascin pattern of the basement membrane was correlated with presence of lymph node metastases (P = 0.04). It is concluded that alterations in tenascin pattern and content reflect complex disturbances in the interaction of inflamed/neoplastic colon epithelium and underlying matrix, leading to an organoid induction of tenascin in the inflammatory context and to induction together with structural abnormalities in neoplasia.

Adhesion molecules VLA-1 to VLA-6 define discrete stages of peripheral B lymphocyte development and characterize different types of B cell neoplasia

VLA-1 to VLA-6 are cell-surface molecules binding to matrix molecules such as collagen, fibronectin, epiligrin, and laminin. In addition, VLA-4 binds to VCAM-1 and ICAM-2, thus mediating intercellular adhesion prerogative for lymphocyte extravasation or 'homing'. Using frozen tissue of normal lymphoid organs and of 100 morphologically and immunologically typed B cell neoplasias, monoclonal antibodies to all six VAL-alpha and to the common beta-chain were applied to serial sections. VLAs were found differentially expressed in cytologically and microtopographically defined B-cell subsets [follicular mantle zone cells (MZ), follicular center cells (FC), extrafollicular cells (EF), and plasma cells (PC)] of normal spleen, lymph node, and thymic medulla (which contains an EF compartment). Thus, these cell types, which correspond to discrete stages of B cell development, can also be defined by their VLA status. Acute B lymphoblastic leukemia (ALL) was VLA-1-, 2-, 3 +/-, 4 +/-, 5 +/-, 6-. The VLA-1-, -2 +/-, 3+, -4+, -5+, -6-phenotype of chronic B lymphocytic leukemia (CLL) resembled that of MZ. Hairy cell leukemia (HCL) differed from CLL in its tendency to lack VLA-2, in its consistent lack of VLA-3, and altogether resembled splenic EF in its VLA profile. Mantle zone lymphoma (MZL) consistently expressed VLA-3 and -4 and frequently VLA-5. Nodal follicular center cell lymphomas (FCCL) were VLA-1- and -2- and very rarely expressed VLA-5 and -6. Thus, FCCL although roughly corresponding to FC, tended to aberrantly express VLA-3 and/or VLA-4. Burkitt's lymphoma resembled FCCL but expressed VLA-4 more frequently and at higher levels. Mediastinal clear cell lymphoma of B-cell type differed from FCCL in its regular lack of VLA-3, -5, and -6 and in frequently lacking VLA-4. Medullary plasmacytoma was VLA-1-, -2-, -3 +/-, -4 +/-, -5-, -6+, thus being the only B cell neoplasia which was consistently VLA-6+. With respect to the well-known clinical characteristics of the B cell malignancies examined, the leukemic phenotype might crucially depend on the presence of VLA-5.

Expression of beta 1-integrins, H-CAM (CD44) and LECAM-1 in primary gastro-intestinal B-cell lymphomas as compared to the adhesion receptor profile of the gut-associated lymphoid system, tonsil and peripheral lymph node

beta 1-Integrins (VLA-1 to -6) are cell-surface molecules binding to matrix molecules such as collagen, fibronectin and laminin. VLA-4 is the human homologue to the murine Peyer's patch homing receptor mediating cell/cell adhesion required for lymphocyte extravasation or "homing". Other structures which have a homing-receptor function through recognition of venular endothelium are H-CAM (CD44) and LECAM-1 (LAM-1, human MEL-14 equivalent). In order to elucidate whether these adhesion receptors are expressed in primary gastro-intestinal malignant B-cell lymphomas (GI BmL) which, in this case, might contribute to the initial confinement to this extranodal site, 31 extensively characterized tumors were examined together with reactive lymphoid tissues from small and large intestine, tonsil and lymph node using monoclonal antibodies (MAbs) against these receptors. All types of adhesion receptors were differentially expressed in the cytologically and microtopographically defined B-cell subsets [follicular center cells (FC), mantle-zone cells (MZ), extrafollicular cells (EF) and plasma cells (PC)] of the normal B-cell system. With the exception of differences in LECAM-1 levels among EF and PC of intestinal vs. nodal vs. tonsillar sites, receptor profiles were almost identical in different lymphoid organs. The expression pattern of these molecules in GI BmL was markedly heterogeneous, mimicking to some extent the receptor equipment of their reactive cellular counterpart. Thus, we failed to find a unifying adhesion receptor profile indicative of a tissue-specific homing of reactive and neoplastic B-cells.

Sporadic loss of leucocyte-function-associated antigen-3 (LFA-3) in colorectal carcinomas

Leucocyte-function-associated antigen-3 (LFA-3) is a cell surface glycoprotein involved in T-cell/target cell interaction. The expression of LFA-3 on the cell surface was found to be inevitably associated with the expression of HLA molecules. Loss of LFA-3 or HLA proteins on tumour cells might result in ineffective T-cell/target cell interaction and a failure of immunological tumour surveillance. Immunohistochemistry revealed that LFA-3 is expressed in normal colonic epithelium; however, in a minor fraction of colonic adenomas and in 50.3% of colorectal carcinomas LFA-3 expression was reduced or even absent. To investigate whether the presence or absence of LFA-3 in colorectal carcinomas influences the relapse rate and time of tumour-related death, 149 patients who underwent putatively curative surgery were surveyed for a maximum of 65 months (mean 48 months). In contrast to the prognostic role of tumour stage and grade, the presence versus absence of LFA-3 was not correlated with recurrence or survival. Regarding survival and growth of residual tumour cells after potentially curative resection of the initial tumour burden, we conclude that the status of LFA-3 expression in colorectal carcinoma seems to be irrelevant in vivo.

Expression of VLA-alpha 2, VLA-alpha 6, and VLA-beta 1 chains in normal mucosa and adenomas of the colon, and in colon carcinomas and their liver metastases

'Very late antigen' (VLA) proteins are members of the integrin superfamily with cell-surface receptor function and are involved in the cell-cell matrix interaction. They are heterodimers with a common beta 1 chain and different alpha chains counted through VLA-1 to VLA-6. The VLA-2 complex (alpha 2/beta 1) was found to act as collagen receptor on platelets and the VLA-6 complex (alpha 6/beta 1) as laminin receptor. Using monoclonal antibodies and an indirect immunoperoxidase method, we investigated the expression of VLA-alpha 2, VLA-alpha 6, and VLA-beta 1 chains in 20 normal colonic mucosa samples, in 20 colonic adenomas, and in 96 carcinomas together with 10 accompanying liver metastases. All three proteins were expressed throughout the colonic epithelium, except for VLA-alpha 2, which was present in the cryptic gland but was absent on the mucosal surface in some cases. In general, adenomas were strongly positive for the VLA proteins but 3 of 20 cases showed focal VLA-alpha 2-negative areas. The carcinomas revealed considerable heterogeneity of VLA-alpha 2 expression; ie, 59 tumors were completely positive, 35 tumors revealed a focal loss of antigen, and 2 cases were negative. This reduced antigen expression was statistically associated with Dukes' stage C/D (P = 0.003). VLA-alpha 6 was expressed throughout in all tumors. VLA-beta 1 was found extensively expressed in 77 carcinomas, partially expressed in 17 carcinomas, and was absent in 2 carcinomas. As compared to their primary tumors, liver metastases showed roughly corresponding patterns of antigen expression. The down regulation/loss of VLA proteins in a subset of epithelial colon tumors might cause a disturbed cell-cell/cell-matrix interaction that might augment the invasive property of their cells.

Stereology, flow cytometry, and immunohistochemistry of follicular neoplasms of the thyroid gland

A retrospective analysis of surgically resected thyroid cold solitary nodules was performed by stereology, DNA flow cytometry, and immunohistochemistry in 15 follicular adenomas and 15 well-differentiated follicular carcinomas to determine if a differential diagnosis of both follicular neoplasms can be done exclusively from cytologic criteria. Between 150 and 200 tumor cell nuclei (TCN) were studied per case for their TCN profile area, perimeter, and density, as well as for stereologic estimates, including the new parameter, volume-weighted mean particle volume (Vv). Flow-cytometric analyses included measurement of the DNA index and the percentage of cells in S phase and G2M phase. The same tumors were examined for the expression of thyroglobulin and the intermediate filaments vimentin and keratin. Follicular adenomas and follicular carcinomas did not show any significant differences in stereologic estimates related to TCN size. Both groups included similar proportions of diploid and aneuploid neoplasms. Aneuploid follicular neoplasms showed a significantly greater area, perimeter, and volume of TCN as compared with diploid tumors, regardless of their histologic diagnosis. Follicular adenomas and follicular carcinomas expressed a similar staining pattern for the tested immunoreagents, with a few cases coexpressing vimentin and keratin. From our results, a differential diagnosis of follicular neoplasms cannot be performed on the basis of cytologic aspirates exclusively. Infiltration of capsula or vessels remains the only safe indicator of malignancy in the absence of metastases. The lack of cytologic differences suggests that some follicular adenomas are preinvasive carcinomas, not yet showing infiltrative growth at the time of resection.