p53 protein expression and oestrogen and progesterone receptor status in invasive ductal breast carcinomas

p53 protein expression and oestrogen and progesterone receptor status in invasive ductal breast carcinomas The p53 protein expression and oestrogen and progesterone receptors status was investigated in correlation to the grade of malignancy of primary breast carcinomas. Our material constituted imprints from surgical biopsies of 75 invasive ductal breast cancer cases. The p53 protein expression was investigated immunocytologically using the monoclonal antibody p53 DO-7 (DAKO). A biochemical DCC method was applied for the detection of oestrogen and progesterone receptors for all tumours. Fifty-one percent of breast cancer cases were p53 protein positive. A statistically significant association of p53 protein expression and high tumour grade was found (chi2=23.72, d.f.=2, P < 0.001). A statistically significant association was also found between oestrogen and progesterone receptor positive cases and the grade of malignancy (P < 0.001). A negative association between p53 protein expression and oestrogen (ER) and progesterone receptors (PgR) positivity was found. From our results it appears that it is possible to distinguish from grade II tumours two subgroups of cases, one with low malignancy potential and p53 (-), ER (+), PgR (+), and another subgroup with high malignancy potential and phenotype p53 (+), ER (-), PgR (-). The last subset of patients could actually benefit from adjuvant therapy.     

Nuclear image analysis of immunohistochemically stained cells in breast carcinomas

Hitherto, the relationship between malignancy-associated morphological features in single tumour cells and the expression of markers indicating functional properties of these cells remained widely unknown. This study was aimed at describing differences in the size, shape and chromatin structure between tumour cells with different marker expression for progesterone receptors (PgR) and p53. Two series of breast cancers, consisting of 50 PgR-positive, and 39 p53-negative and 49 p53-positive mammary carcinomas, were investigated. The immunohistochemical staining was performed on paraffin sections using 3-amino-9-ethylcarbazole as the chromogenic substrate. By means of a cytometry workstation equipped with a computer-controlled motorised scanning stage, about 500 positive and negative tumour cells in each case were localised in the microscope and categorised by a scoring system for their staining intensity. After destaining, the tissue sections were Feulgen-stained. Then, all the tumour cells were relocated automatically and analysed by high resolution image cytometry. Among the numerous size, shape, and texture features used in the system, several variables of the nuclear contour and chromatin structure were found to be significantly different between the positive and negative tumour cell populations. Nuclei without PgR had more malignancy-associated morphological features than PgR-positive cells. Whereas p53-negative nuclei had a higher degree of regularity, their positive counterparts exhibited higher DNA ploidy values.     

Estrogen- and progesterone receptors in normal cycling endometrium as studied by end-point titration

A thorough knowledge of the normal physiological fluctuations in estrogen-(ER) and progesterone receptors (PgR) is essential to characterize the changes in ER and PgR in the abnormal endometrium. We investigated the distribution of ER and PgR in frozen human cycling endometrial tissue using the commercially available ER-and PgR-ICA kits. Two-fold end-point titration (EPT) of ER and PgR antibodies was implemented to semi-quantitate more accurately ER and PgR. Semiquantitation of ER and PgR using EPT was significantly correlated to results obtained using either simple scoring or enzyme-immunoassay (EIA) methods. ER and PgR staining fluctuated in relation to the menstrual cycle. In most subphases PgR exceeded ER in both epithelial and stromal cells. Highest levels of ER and PgR were demonstrated in the glands of the functionalis in mid-to-late proliferative phases, whereas both receptors were almost undetectable by immunohistology in the glands of mid-to-late secretory phases. Endometrial stromal cells had high and nearly constant EPT values for PgR, but low values for ER througout the menstrual cycle. EPT values for ER and PgR were generally higher in the basalis than in the functionalis but showed similar cyclic fluctuations. Our results further substantiate the view that the response to hormonal stimulation is cell-type specific, and suggest differences in steroid metabolism according to cell type and layer.     

Role of bone marrow imprints in haematological diagnosis: a detailed study of 3781 cases

X. Gong, X. Lu, X. Wu, R. Xu, Q. Tang, G. Xu, L. Wang, X. Zhang and X. Zhao Role of bone marrow imprints in haematological diagnosis: a detailed study of 3781 cases Objectives: To explore the role of imprints in routine bone marrow (BM) diagnosis. Methods: The cellularity and diagnostic accuracy of BM imprints, aspirate smears and trephine biopsy sections from 3781 patients were assessed using routine cytochemical staining. Seventy‐nine cases of lymphoma and 114 cases of plasma cell myeloma (PCM) were selected for correlation analysis of tumour cell infiltration patterns. Another 21 cases of lymphoma were selected to detect t(14;18)(q32;q21) and t(11;14)(q13;q32) by fluorescent in situ hybridization (FISH) on BM imprints, and the G‐banding technique was performed for comparison. Results: BM imprints were better than smears for evaluating cellularity. In the BM imprint group, diagnostic accuracy for metastatic carcinoma, myeloproliferative neoplasm, myelodysplastic/myeloproliferative neoplasm and PCM was better than in the smear group, while accuracy for megaloblastic anaemia, acute myeloid leukaemia, refractory cytopenia with unilineage or multilineage dysplasia, refractory anaemia with excess blasts and lymphoplasmacytic lymphoma was higher than in the section group, but not statistically different from the smear group. Good correlation of infiltration patterns of lymphoma and myeloma cells was found between BM imprints and sections (r = 0.90 and 0.78, respectively). Detection of t(11;14)(q13;q32) by FISH on imprints was higher than G‐banding analysis. Conclusions: BM imprints show features of both smears and trephine sections. Imprints are superior to smears for evaluation of cellularity, and are also better than sections for analysis of cytological changes. In addition, FISH on BM imprints markedly improves the identification of chromosomal abnormalities.     

Comparison of the oestrogen and progesterone receptor status in primary breast carcinomas as evaluated by immunohistochemistry and immunocytochemistry: a consecutive series of 267 patients

A.M. Domanski, N. Monsef, H.A. Domanski, D. Grabau and M. Fernö
Comparison of the oestrogen and progesterone receptor status in primary breast carcinomas as evaluated by immunohistochemistry and immunocytochemistry: a consecutive series of 267 patients Objective: The use of cytological specimens to evaluate tumour biomarkers in metastatic breast cancer lesions has attracted increased interest because of the considerable number of reports that have shown discordance between the primary tumour and metastatic lesion. Oestrogen receptor (ER) and progesterone receptor (PgR) assays are crucial for the management of patients with breast cancer, in both adjuvant and palliative settings. The aim of this study was to compare the ER and PgR immunocytochemical analysis of fine needle aspiration (FNA) samples with the immunohistochemistry (IHC) of surgical specimens and core biopsies from primary breast cancers. Methods: The FNA specimens were prepared as cell blocks (n = 25) or ThinPreps (n = 258) for the immunocytochemistry (IC) ER and PgR analyses. Sixteen patients were excluded because of lack of follow‐up (n = 1), neoadjuvant therapy (n = 3) or cell counts in their fine needle aspirates that were too low (n = 12). The results of IC on 25 cell blocks and 242 ThinPreps were compared with IHC on the corresponding core needle biopsies (n = 16) or excised tumours (n = 251). The ER and PgR status was defined as negative (when less than 10% of the nuclei were stained) or positive (when equal or more than 10% of the nuclei were stained). Kappa statistics were used to evaluate the concordance. Results: The ER concordance was 98% with ThinPrep (κ = 0.93) and 92% with cell block (κ = 0.82). The corresponding values for PgR were 96% (κ = 0.91) and 96% (κ = 0.92). Conclusions: Our results confirm that, in cases in which biopsies or surgical specimens are not available, IC (with either cell block or ThinPrep techniques) is a reliable method for the determination of the ER and PgR status performed under strict conditions using primary breast carcinomas, and is therefore potentially useful in metastatic settings.     

Steroid receptors in the developing and the adult rabbit endocervix and in endocervical epithelial cells isolated by flow cytometry

Immunocytochemistry with monoclonal antibodies H222 and JZB39 was used to study nuclear estrogen (ER) and progesterone (PgR) receptors, respectively, in the cervix during differentiation and in the adult rabbit. The undifferentiated state of the cervix of 2-week-old rabbits correlates with a paucity of immunoreactive nuclear ER, while the epithelium of most of these animals showed moderate immunostaining for the nuclear PgR. The cervical epithelium, stroma and muscle cells of 1-month-old rabbits, showed weak immunostaining for the ER, while staining for PgR remained comparable to that of 2-week-old rabbits. For 2-4-month old rabbits the epithelium was characterized by moderate immunostaining for the nuclear ER and strong immunostaining for the PgR. Strong, heterogeneous immunostaining for nuclear ER and PgR receptors in endocervical epithelial cells from 6-month-old (adult), estrous rabbits suggested there are subpopulations of cells that express differential sensitivity to steroid hormones. In order to characterize such subpopulations, live endocervical epithelial cells were sorted with a flow cytometer on the basis of forward angle light scatter (FSC) and side scatter (SSC) signals which correlated with cell size and secretory granule content, respectively. Secretory cells, as verified by ultrastructural analysis and histochemical staining, expressed the highest FSC and SSC signals and were designated fraction "a". Changes in the hormonal status of the animals altered the intrinsic light scatter properties of fraction "a" cells as follows: maximum FSC and SSC signals were reported for cells from estrous animals; ovariectomy or progesterone-dominance decreased cell size (FCS) and secretory granule content (SSC), while treatment of ovariectomized rabbits with estradiol increased both parameters. When fraction "a" cells from estrous rabbits were incubated with the monoclonal antibodies, two distinct subpopulations of secretory cells were identified by intensity and pattern of nuclear staining for the ER and PgR. Changes in the hormonal status of the animals produced changes in the intensity of nuclear immunostaining, however both cell types remained distinguishable on the basis of immunostain pattern reflecting either permanent or transitory differences in them, and differential hormone sensitivity. The presence of nuclear ER and PgR proteins in these cells confirms their function is bireceptor-mediated.     

Effect of Fixation on Interphase Cytogenetic Analysis by Direct Fluorescence in Situ Hybridization on Cell Imprints

The direct fluorescent in situ hybridization (FISH) technique using a centromere-specific DNA probe for chromosome 11 was applied on fresh tissue imprints from melanomas and pituitary adenomas. The cell imprints were fixed in acetone and formalin, and the influence of fixation was evaluated. Acetone fixed imprints gave a sharp and intense fluorescent signal in a large number of cells from both tumors without any pretreatment. In contrast, formalin fixed imprints disclosed a weak hybridization signal in a few cells even after careful enzymatic digestion. Direct FISH on acetone fixed cell imprints represents a simple and time saving technique applicable to any laboratory for the study of numerical chromosomal abnormalities.     

Cytology of Ki-1 (CD-30) positive large cell lymphoma

To study the cytomorphology of Ki-1 (CD-30) positive anaplastic large cell lymphoma, imprints and fine needle aspirates from a total of 20 of these tumours were collected. The results show that these tumours have a highly pleomorphic and variable picture, which can be easily confused with other poorly differentiated large cell tumours. Typical morphological differences between the B-cell and T-cell variety were found. B-cell tumours more often showed nuclear multilobation, a fine, hypochromatic chromatin pattern, and many lymphoglandular bodies. T-cell tumours more often displayed multinucleation, window nuclei, and a hyperchromatic coarse chromatin pattern. The diagnosis of anaplastic large cell Ki-1 positive lymphoma, B-cell type or T-cell type, should be included in the differential diagnosis of any large cell tumour of uncertain origin with mainly dissociated tumour cells. Immunocytochemistry is recommended to establish the correct diagnosis.     

Clinicopathologic Characteristics of Oestrogen Receptor-Positive/Progesterone Receptor-Negative/Her2-Negative Breast Cancer According to a Novel Definition of Negative Progesterone Receptor Status: A Large Population-Based Study from China

PurposeA lack of progesterone receptor (PgR) expression in oestrogen receptor-positive (ER+) tumours is associated with worse survival. PgR status is usually defined as positive or negative using 1% positive nuclei as a cut-off point. In this study, we aimed to assess the clinicopathologic characteristics of ER+/PgR-/HER2- tumours by comparing them with ER+/PgR+/HER2- tumours using a PgR cut-off point of 20% as a divisive criterion.MethodsWe analysed 1,522 patients with primary breast cancer who had undergone surgery at the Cancer Center of Fudan University between 2012 and 2014. Age, grade, tumour size, lymph node status and lymphovascular invasion were assessed. Multinomial logistic regression, linear regression and chi-square test models were applied to assess associations between ER, PR and clinical features.ResultsER+/PgR-/HER2- tumours showed poorer clinicopathologic characteristics relative to ER+/PgR+/HER2- tumours using a PgR threshold of 20% instead of 1%. The clinicopathologic characteristics did not differ between tumours with purely negative PgR expression and tumours with a PgR percentage ranging from 1% to 19%. The prognostic significance of PR expression appeared more pronounced in patients under a high Ki-67 status than those under a low Ki-67 status.ConclusionsBased on these findings, we propose the use of a novel threshold of 20% to define PgR status. Nevertheless, the impact of this new criterion on patient management and clinical treatment requires additional study.     

Image cytometry of aneuploidy, growth fraction (MoAb Ki-67) and hormone receptors (ER, PR) immunocytochemical assays in breast carcinomas

DNA nuclear content was assessed in human breast carcinomas (n = 132) using image cytometry. Optical density histograms of Feulgen stained cell imprints from fresh tissue samples, subsequently frozen for immunocytochemical assays, were determined by the SAMBA system and used for the DNA index, the ploidy balance (PB) and the proliferation index (PI) computation. The three parameters were correlated to (i) histological data (tumour grade, vascular and/or lymph node invasion) and to (ii) growth fraction (Ki67), hormone receptor antigenic sites (ER, PR) and intramedullar (bone marrow) biopsies and anti-KL1-positive epithelial cells. It was shown that 57% of breast carcinomas were aneuploid. Aneuploidy PI significantly correlated to the criteria of poor prognosis such as high tumour grade, vascular and lymphatic invasion and to increased Ki67-positive cells, and the absence of or low ER and PR. Since image cytometry is easy to handle and perfectly suitable for current diagnostic practice in pathology departments, particularly for tumour cell ploidy assessment and standardized analysis of immunostaining procedures with morphological control of the preparation, we conclude that image cytometry, as performed with the SAMBA, must be regarded as a relevant tool for prognosis evaluation and therapy guidance in individual patients.     

Cytologic diagnosis and subtyping of rhabdomyosarcoma

atahan s,., aksu ö. and ekinci c. (1998) Cytopathology 9, 389–397
Cytologic diagnosis and subtyping of rhabdomyosarcoma
We reviewed the cytological findings of 38 cases of rhabdomyosarcoma (RMS) with histological confirmation performed during a period of 15 years and proposed a morphological subtyping based on the most prominent cytologic features. Seventeen of these cases were alveolar, 14 cases embryonal, and seven botryoid subtypes. From these cases, a total of 43 samples, of which 37 were fine needle aspiration (FNA) biopsies and six were touch imprints, were evaluated. Detailed cellular features were identified which enabled differentiation into histological subtypes. In the alveolar RMSs, most tumour cells were small and lymphocyte-like, having finely granular chromatin. The finding of cells with more abundant cytoplasm, eccentrically located nuclei and bi/multinucleated tumour cells in a background of mucosubstance helped in the differential diagnosis. Two cell types, including large, tadpole or ribbon-shaped tumour cells and small, round cells with scant cytoplasm, were seen in embryonal RMSs. In botryoid RMSs, a cell type with tightly grouped nuclei within elongated cytoplasm similar to a myotubular structure was observed in addition to the two cell types of embryonal RMSs. We conclude that with experience it will be possible to subtype these tumours by cytologic examination alone.     

Animal age-, dose- and cell line-dependent growth of human neuroblastoma in nude mice. A statistical analysis.

Cells lines from human neuroblastoma (NB) and T/lymphoma (T-L) were injected subcutaneously (sc) in female CD1 nu/nu athymic nude mice. Results obtained after the observation of tumour growth were statistically analyzed by SAS. The following four parameters were considered: 1) dose of injected cells, 2) type of injected tumour (NB or T-L), 3) age of mice after individuation of three groups of animals (group A, 4-9 weeks old, group B, 9-20 weeks old, group C, > 20 weeks old), 4) injected cell line within the same tumour type. Latency time (LT), corresponding to the interval between cell inoculum and the appearance of a 5 mm diameter subcutaneous mass, and survival time (ST), corresponding to the interval between cell inoculum and the appearance of a 20 mm diameter subcutaneous tumour mass, were considered to evaluate tumour growth. Results showed that mass progression is affected by the number of injected cells and both LT and ST are age- and dose-dependent; furthermore, significant differences were recorded by using different NB and T-L cell lines. Group C showed longer LT than other groups; group B animals showed a statistically significant longer ST than groups A and C (p < 0.001). Our results indicate that growth of human NB in athymic mice is faster in young animals, which also show a significantly poorer prognosis, while better ST was observed in old and middle-aged animals. Results show statistically significant differences of both LT and ST in animals differing in age and in animals inoculated with different cell amounts. These results seem not to be related with biological properties of NB cells too, since neither the occurrence of MYCN amplification nor chromosome 1p deletion significantly modified such behaviour.     

Nuclear DNA ploidy in mammary carcinomas; using nuclear size as co-parameter reveals more complex patterns.

Static DNA measurements using nuclear size as a co-parameter have been made on cell populations from 106 consecutive patients with proper imprints from fresh tumour tissues or fine-needle aspirates. When DNA content is plotted against the nuclear size of each individual cancer cell in a scatter diagram, different patterns are found. These patterns indicate the presence of subpopulations, which may be overlooked using conventional flow cytometric analysis or other techniques relying only on the nuclear DNA content. The presence of these subpopulations might, in addition, interfere with a correct definition and estimation of the percentage of S-phase cells.     

Image cytometry of estrogen receptors in breast carcinomas

A significant level of estrogen receptors (ER) in breast cancer cells is an indication of tumor differentiation and suggests that a homeostatic control of cell growth may persist in these cancers. In medical practice, the Dextran-coated charcoal assays (DCCA) are still the most frequently used test to characterize patients having ER-positive malignant breast tumors and for whom hormonal therapy is justified. Nevertheless, this routine biochemical technique is not satisfactory because it is a broad method unsuitable for revealing receptor tissue heterogeneity. However, immunocytochemical labeling, such as the ER-ICA method, which involves a monoclonal antibody linked to peroxidase, is a specific reaction for this purpose but which until now was not quantitative. The present study uses an original cell preparation technique combining the PAP reaction with toluidine blue counterstain for image analysis on the SAMBA system. Special software has been developed for the quantitative analysis of immunocytochemistry in cancers. Results obtained showed a high correlation between the DCCA values and the score derived from the mean ER concentration per positive tumor cell and the labeling index. In addition, intracell and intratumor heterogeneity can be displayed according to several parameters and were shown to vary according to tumor and to antiestrogen (Tamoxifen) presurgical therapy.     

Hollow spheroids in ascites of ovarian clear cell carcinoma: how are they formed and how do they behave?

N. Kato, K. Narutomi, M. Fukase and T. Motoyama Hollow spheroids in ascites of ovarian clear cell carcinoma: how are they formed and how do they behave? Objective: Although the multicellular aggregates (spheroids) in malignant ascites are usually solid throughout, they sometimes have acellular hollow spaces, especially in ascites of ovarian clear cell carcinoma. The purpose of this study is to analyse the origin and behaviour of hollow spheroids. Methods: Archival cytological and histological specimens of 32 ovarian carcinomas, including 12 clear cell carcinomas, were reviewed. HAC‐2, a clear cell carcinoma cell line, was injected into the abdominal cavity of nude mice for direct comparison of ascitic cytology and tumour histology. Spheroids that were collected from nude mice ascites were cultured in vitro to observe their behaviour. Results: Five of six clear cell carcinomas with hollow spheroids showed spherule‐like hyaluronan‐rich stroma in their tumour tissue, whereas those without hollow spheroids did not. After heterotransplantation, both ascites and tumour imprints showed small or large hollow spheroids. Hyaluronan was detected in the former but not in the latter. The abdominal tumours showed compact spherule‐like hyaluronan‐rich stroma, enlarged oedematous stroma or intermediate stroma. In both size and hyaluronan status, small and large hollow spheroids were approximately comparable to spherule‐like hyaluronan‐rich stroma and oedematous stroma, respectively. During culture in vitro, hollow spheroids were maintained as hollow spheroids in suspension, and produced daughter hollow spheroids. Conclusions: The hollow space in the spheroids originates from spherule‐like hyaluronan‐rich stroma, where water trapping by hyaluronan causes enlargement of the space. The matrix within the hollow space serves as a scaffold that regulates cell polarity and matrix production.     

Progesterone receptor detection and quantification in breast tumors by bivariate immunofluorescence/DNA flow cytometry

A method was developed for the detection of progesterone receptors (PgR) by flow cytometry (FCM) in cell suspensions obtained from mechanically dispersed fragments of operated breast cancers. Two monoclonal antibodies were tested for sensitivity and specificity on four breast cancer cell lines of known PgR expression and a calibration curve thus established. A simple procedure was used to calculate the level of PgR expression, taking into account the relative displacement of total cellular fluorescence compared to nonspecific fluorescence for each sample and the average DNA content of the cells derived from the corresponding histograms. The PgR-specific immunofluorescence of the tumor specimens measured in arbitrary units (channels) was then transformed to fmoles/mg DNA by comparison with the calibration curve. The FCM-derived results were compared with those of a conventional immunoenzymatic PgR assay on 30 surgical samples. PgR content ranged from 10 to 22,000 fmoles/mg DNA and linear regression analysis yielded a good correlation (r = 0.86). With a threshold of positivity of 300 fmoles/mg DNA, the two methods concurred for 28 of 30 tumors (93%). Nine specimens were analyzed repeatedly, showing good reproducibility. This method could prove to be more useful than the biochemical assays on homogenates, since it allows the simultaneous analysis of receptor expression in individual cells and of DNA index (ploidy).     

An investigation of cut-points for primary breast cancer oestrogen and progesterone receptor assays

Oestrogen and progesterone receptor (ER and PgR) assay values are frequently used in medical decision-making for breast cancer patients. We have proposed statistical standardization of receptor assay values to improve inter-laboratory comparability, and now report the use of standardized log units (SLU) to investigate the effects of ER and PgR cut-points on time to first recurrence outside the breast (DFS). Between 1980 and 1986, there were 678 primary breast cancer patients treated at the Henrietta Banting Breast Centre (HBBC). The effects of ER and PgR cut-points were examined with multivariate analyses considering the variables: age, tumour size, nodal status, weight and adjuvant treatment. We considered receptor assay cut-points ranging from −1.0 to +1.0 SLU (ER between 7 and 166 fmol/mg protein; PgR between 7 and 181 fmol/mg protein). PgR was included in the multivariate prognostic models more often than ER, although patients had a better prognosis with both larger ER and PgR values. There was no best cut-point for ER or PgR, and there was strong evidence that ER and PgR should be considered as continuous rather than dichotomous (negative, positive) variables. Patient prognosis should also be more comparable with SLU.     

Malignant lymphoma of follicle centre cells with marked nuclear lobation

Four cases of malignant B-cell lymphoma characterized by a conspicuous component of tumour cells with markedly lobatated nuclei are described. Two exhibited a follicular and two a diffuse growth pattern. The tumour cell population formed a continuous spectrum comprising both cells resembling normal follicle centre cells and multilobated lymphoma cells. Cytomorphological analysis of the multilobated cell group indicated a differentiation series from centroblast-like cells with moderately lobated nuclei to large and medium-sized cells with marked nuclear lobation which revealed features of centrocytes. In three cases (1, 3, and 4) the majority of these multilobated cells showed plasmacytoid differentiation in their cytoplasm in conjunction with the synthesis of monotypical cytoplasmic immunoglobulin. No plasmacytoid features were present in a fourth case (2). In only one case (4) monotypical surface immunoglobulin was detectable on the tumour cells. A close relationship between the multilobated tumour cells and follicle centre cells was further substantiated by the finding of a similar cell variant in the follicle centres of a control group of non-neoplastic lymph nodes. It included cells with plasmacytoid differentiation which synthesized polytypical immunoglobulin. We consider this type of B-cell lymphoma with a conspicuous component of cells with lobated nuclei as a variant of malignant lymphoma, centroblastic/centrocytic.     

Evaluation of c-erbB-2 overexpression and Her-2/neu gene copy number heterogeneity in Barrett's adenocarcinoma.

Amplification of the Her-2/neu gene is accompanied by overexpression of its cell surface receptor product, c-erbB-2 protein. To investigate the degree of intratumoural heterogeneity we applied immunohistochemistry in primary Barrett's adenocarcinoma (BCA) (n = 6) and dysplasia adjacent to the carcinoma (n = 4). In addition, fluorescence in situ hybridisation (FISH) was performed in primary BCA (n = 5) and dysplastic areas (n = 4). For an objective evaluation digital image analysis and laser scanning microscopy were used. Five of six BCA showed a marked intratumoral heterogeneous staining pattern ranging from areas in which the tumour cells were negative or faintly positive to tumour areas with a strong staining of the entire membrane. Among the two dysplastic areas also a heterogeneous staining pattern was observed. FISH analysis revealed marked heterogeneity of intratumoral gene copy number changes in all BCA showing populations with different fractions of cells with polysomy, low level amplification and high level amplification. One dysplasia showed a minor population with Her-2/neu signal clusters. In conclusion, we observed marked intratumoural heterogeneity of c-erbB-2 protein overexpression and Her-2/neu gene copy number in the majority of the primary BCA analyzed. Digital image analysis and laser scanning microscopy were helpful in quantifying the variations in protein expression and DNA copy number in individual tumour cells. The observed heterogeneity could hamper the exact diagnostic determination of the c-erbB-2 status in small biopsies and possibly influence the effectiveness of a potential c-erbB-2 targeting therapy. Figures on http://www.esacp.org/acp/2000/20-1/walch.htm+ ++.     

Differential effects of calcium deprivation on the cytoskeleton of non-tumorigenic and tumorigenic rat liver cells in culture

Normal rat liver T51B epithelial cells and Morris no. 7795 hepatoma cells growing exponentially were exposed for 24 h to standard medium containing low (0.02 mM) calcium, a concentration which drastically reduces the proliferation of normal but not tumour cells. Cell surface morphology was examined by scanning electron microscopy (SEM); and the distribution and organization of microtubules, cytokeratin and vimentin filaments, and microfilaments were analysed by indirect immunofluorescence microscopy using specific antibodies. Calcium deprivation caused the loss of intercellular cohesion in both cell types and the appearance of some microvilli and blebs, particularly on tumour cells. However, marked differential (normal vs tumour cells) effects on the organizational integrity of the cytoskeleton fibrillar network were observed. Extracellular calcium deprivation led to a particular rearrangement of microtubules, and a perinuclear accumulation of cytokeratin and vimentin filaments in normal, but not in tumour cells. A massive concentration of actin-containing microfilaments was observed in the cell periphery and blebs of hepatoma cells. In the light of the possible involvement of calcium in controlling cytoskeleton assembly, the differing cytoskeletal changes of the two cell types may be linked to their diffferent proliferative capabilities in low-calcium medium.