Triple-negative breast cancer: the impact of guideline-adherent adjuvant treatment on survival--a retrospective multi-centre cohort study.

Triple-negative breast cancer (TNBC) (ER-/PGR-/erb-2-) constitutes an aggressive subtype in breast cancer because it is accompanied by a significant decrease in overall survival (OAS) and recurrence-free survival (RFS) compared with hormone receptor positive breast cancers. This retrospective cohort study investigates the following issues: (1) Is there an impact of guideline-adherent treatment on RFS and OAS in TNBC? (2) Which adjuvant treatment has the most important impact on RFS and OAS in TNBC? This German retrospective multi-centre cohort study included 3,658 patients with primary breast cancer recruited from 2000 to 2005. The definition of guideline adherence was based on the German national S3 guideline for diagnosis and treatment of breast cancer (2004). A total of 371 patients (10.1%) had TNBC. Compared with HR+/erb-2- breast cancer (P = 0.001; HR = 1.75; 95% CI: 1.27-2.40), the recurrence rate of TNBC was significantly higher (P < 0.001; HR = 2.86; 95% CI: 2.17-3.76). Furthermore, the 5-year RFS and OAS was significantly lower in TNBC (RFS: 74.8% [95% CI: 68.8-80.8%] vs. 86.5% [95% CI: 84.6-88.4%] [log-rank P = 0.0001]) (OAS: 75.8% [95% CI: 69.9-81.8%] vs. 86.0% [95% CI: 84.1-87.9%] [log-rank P = 0.0001]). The most important parameters predicting RFS and OAS in TNBC after receiving guideline-conform chemotherapy are guideline-adherent surgery, radiotherapy, nodal status and grading. Overall, 66.8% TNBC were found with one or more (18%) guideline violations, which subsequently impaired OAS and RFS. The most important impact on OAS and RFS in TNBC patients was because of guideline violations (GV) concerning adjuvant radiotherapy and GV concerning adjuvant chemotherapy. Patients with TNBC primarily have a worse prognosis in terms of RFS and OAS than patients of a primarily non-TNBC phenotype. There is a strong association between guideline-adherent adjuvant treatment and improved survival outcome in TNBC. The outcome significantly decreases with the number of guideline violations.

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.

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]. / Die endoskopisch axilläre Lymphonodektomie--Ergebnisse einer Pilotstudie.

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.

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 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.

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.