Diagnostic value of p53 protein and flow cytometric DNA analysis in the study of serous effusions

OBJECTIVE: To investigate the diagnostic value of p53 protein and DNA analysis in the study of serous effusions. STUDY DESIGN: A total of 76 samples of serous effusions were studied by immunohistochemistry for p53 protein and flow cytometric (FCM) DNA analysis. The results were correlated with final cytologic diagnoses, which were confirmed by immunohistochemistry using antibodies against cytokeratin, carcinoembryonic antigen, epithelial membrane antigen and fibronectin. RESULTS: Final cytologic diagnoses included 28 malignant effusions and 48 benign effusions. No expression of p53 protein was seen in benign effusions. In contrast, p53 protein expression was seen in 19/28 (sensitivity 68%) malignant effusions. FCM detected aneuploid cells in 12/28 (43% sensitivity) of malignant and 0/46 of benign effusions. Immunohistochemical determination of p53 protein combined with FCM DNA analysis increased sensitivity to 79%. CONCLUSION: Immunohistochemical determination of p53 protein and FCM DNA analysis can aid in making an accurate and specific diagnosis of serous effusions, but the principal limitation of these tests is their relatively low sensitivity.     

Immunohistochemical panel for distinguishing between carcinoma and reactive mesothelial cells in serious effusions

OBJECTIVE: This study was designed to assess whether a new panel of antibodies is a useful adjunct in the differential diagnosis of carcinoma and reactive mesothelial cells. STUDY DESIGN: Complete, one-hour immunohistochemistry using antibodies against cytokeratin (CK), carcinoembryonic antigen (CEA), epithelial membrane antigen (EMA) and fibronectin was applied to cell blocks from 76 pleural and peritoneal fluid specimens. Fifty patients with histologically diagnosed primary carcinomas and 26 without evidence of malignancy were included. The results were correlated with routine cytologic results. RESULTS: The final cytologic diagnoses were 28 malignant effusions and 48 benign effusions. CEA and EMA were present in 25 (89%) and 24 (86%) of 28 carcinoma cases, respectively. These determinants were absent from reactive mesothelial cells. Fibronectin strongly labeled reactive mesothelial cells, with no staining of carcinoma cells. Carcinoma cells expressed at least two antibodies to CK, CEA and EMA and were negative to fibronectin. Reactive mesothelial cells expressed both CK and fibronectin. In 6 of 28 carcinoma cases (21%) the immunohistochemical panel identified carcinoma cells that were not recognized initially on routine cytologic examination. CONCLUSION: A panel of CEA, EMA and fibronectin monoclonal antibodies appears to be suitable for distinguishing between carcinoma cells and reactive mesothelial cells in serous effusions.     

Neurofibroma and cellular neurofibroma with atypia: a report of 14 tumors

The clinical significance of nuclear atypia in neurofibromas that lack necrosis or significant mitotic activity has not been systematically studied. We reviewed 14 neurofibromas from six patients with mild to marked nuclear atypia, with low mitotic activity in some tumors. Five tumors also had areas of increased cellularity consistent with cellular neurofibroma. Necrosis was absent. All patients were treated by conservative excision. Clinical follow-up, ranging from 8 months to 6 years, showed that none of the tumors recurred or metastasized. To further characterize these neoplasms, we assessed p53 expression, proliferation rate, and DNA content because these methods have been suggested by others as useful in differentiating benign from malignant nerve sheath tumors. p53 expression was detected by immunostaining in one tumor with 5% positive cells and in two tumors with rare positive cells (<1%). The remaining 11 tumors were negative. Tumor cell proliferation rate as determined by Ki-67 immunostaining showed <5% positive cells in 13 tumors. In one tumor, 10% of the cells were Ki-67 positive. Using flow cytometry methods and paraffin-embedded tissue, all tumors had diploid DNA content with an S phase fraction ranging from 5.2% to 18.2% (mean 9.4%). No significant differences were observed between the neurofibromas and cellular neurofibromas. For comparison, we studied three malignant peripheral nerve sheath tumors (MPNSTs). All MPNSTs had relatively high p53 (range 10-16%; mean 12%) and Ki-67 (range 32-42%; mean 38.0%) staining. One of the MPNSTs was aneuploid. The S phase fraction of the MPNSTs ranged from 8.1% to 51.8% (mean 28.6%). These results suggest that clinically benign neurofibromas, both usual and cellular types, can have significant cytologic atypia that can be accompanied by low mitotic activity. Conservative surgical excision for these tumors is adequate. The results of p53 and Ki-67 immunostaining and DNA content and S-phase analysis by flow cytometry support this interpretation. In addition, in tumors with borderline histologic findings, results of these ancillary studies may be useful in distinguishing benign from malignant nerve sheath tumors.     

Immunohistochemical detection of p53 and Bcl-2 in colorectal carcinoma: no evidence for prognostic significance

To evaluate the prognostic significance of immunohistochemically detected p53 and Bcl-2 proteins in colorectal cancer, tissue sections from 238 paraffin-embedded colorectal carcinomas were immunostained for p53 (MAb DO-7 and CM-1 antiserum) and Bcl-2 (MAb Bcl-2:124). Staining patterns were assessed semiquantitatively and correlated with each other and with sex, age, tumour site, Dukes' classification, tumour differentiation, mucinous characteristics, lymphocyte and eosinophilic granulocyte infiltration, and patient survival. In our series, 35% of carcinomas showed no nuclear staining and 34% (DO-7) to 40% (CM-1) showed staining in over 30% of tumour cell nuclei. A majority of carcinomas that had been immunostained with CM-1 showed cytoplasmic staining, but this was not observed with DO-7. With respect to Bcl-2, 51% of tumours were completely negative, 32% displayed weak and 15% moderate staining; only 3% showed strong positive staining. No evidence was found for reciprocity between Bcl-2 expression and nuclear p53 accumulation. From 13 cases containing tumour-associated adenoma, four were Bcl-2 negative in premalignant and malignant cells, in another four cases these cells showed similar staining intensities and in the remaining cases only the malignant colorectal cells were Bcl-2 negative. Therefore, our data indicate that Bcl-2 is dispensable in the progression towards carcinoma. Except for an association between nuclear p53 accumulation and mucinous tumours (P = 0.01), no significant correlation was found between the clinicopathological parameters mentioned above and immunostaining pattern of (nuclear or cytoplasmic) p53 or Bcl-2.     

Fine-needle aspiration biopsy of the breast

Fine-needle aspiration biopsy of the breast was perfomred in 503 cases which were subsequently examined histologically. There were 192 cases of cancer and 311 benign lesions. The cytological technique consisted of fixation in 50% ethyl alcohol, Millipore filtration and Papanicolaou staining. Of the 192 malignant lesions, the aspiration biopsy findings were originally reported as malignant (Papanicolaou Gr. V) in 138 cases (71.9%) and after review of the specimens in 161 cases (83.9%). The figures for strongly suspicious findings (Gr. IV) were 19 (9.9%) originally and 6 (3.1%) after the review, in moderately suspicious findings (Gr. III) 14 (7.3%), respectively. Of the false negative cases four (2.1%) were due to inadequate specimens. In the 311 histologically benign cases malignancy was originally strongly suspected cyologically (Gr. IV) in five (1.4%) and Gr. III findings occurred in 22 suspected cytologically (Gr. IV) in five (1.4%) and Gr. III findings occurred in 22 cases (7.1%). After review, no strongly suspicious findings were left. Gr. III findings numbered nine (2.9%). There were no false psoitive (Gr V) cases in this series. Cytological manifestations are described and some clinicopathological aspects of fine-needle aspiration biospy of the breast are discussed. The orientation period with continuous cytohistological comparisons ie is essential for successful aspiration biopsy diagnosis.     

Usefulness of argyrophilic nucleolar organizer regions score to differentiate suspicious malignancy in pulmonary cytology

OBJECTIVE: Pulmonary cytologic specimens reported as "suspicious for malignancy" pose problems in clinical management. Silver staining for argyrophilic nucleolar organizer regions (AgNOR) has proved useful in making a cytopathologically differential diagnosis between benign and malignant cells. This study aimed to evaluate the usefulness of AgNOR score in the diagnosis of pulmonary cytologic specimens deemed inconclusive by conventional staining methods. METHODS: Pulmonary cytologic specimens initially reported as suspicious for malignancy with Papanicolaou or May-Grünwald-Giemsa (MGG) staining obtained from 35 proved cases were destained then restained using the AgNOR technique. Another 35 cases with clear cytologic diagnosis were also examined for comparison. The median number of dots, defined as the AgNOR score, was used to differentiate malignant from benign specimens. RESULTS: Malignant cases had significantly higher AgNOR scores than benign ones (p<0.001). There were no significant differences among smears previously stained with Papanicolaou or MGG method, among specimens obtained via bronchoscopic brushing, fine-needle aspiration of lung or pleural effusion, or among subgroups of malignant diseases. Based on the results of our previous study, the cutoff value of the AgNOR score to differentiate benignancy from malignancy was set at 6. At this setting, the sensitivity and specificity of AgNOR score were 88% and 80%, respectively, in aiding a differential diagnosis of pulmonary cytologic specimens initially classified as suspicious for malignancy. For those cases with a clear cytologic diagnosis, the sensitivity and specificity of AgNOR score were 92% and 100%, respectively. For all cases, the sensitivity of AgNOR score was 90% and the specificity was also 90%. CONCLUSIONS: The AgNOR score is of value in aiding a differential diagnosis between benign and malignant lesions in pulmonary specimens with equivocal cytologic features.     

Clinicopathologic analysis of bcl-2 immunostaining in breast carcinoma

Tissue sections of 81 breast carcinomas and 19 benign breast tissues were immunostained with a monoclonal antibody to the bcl-2 gene product, a cytoplasmic protein that regulates apoptosis. The degree of immunoreactivity was then compared with clinicopathologic parameters and to immunostaining for mutated p53 gene product. Immunoreactivity for bcl-2 was present consistently in lymphocyte populations and in residual benign lobules. Apocrine metaplasia (n = 6) and lactating breast (n = 1) exhibited minimal bcl-2 expression, whereas duct hyperplasia (n = 10) showed staining of cells primarily at the periphery of the involved structure and adenosis (n = 7) displayed staining in a majority of cells. Neoplastic epithelial bcl-2 immunoreactivity was negative or minimally positive (staining in 1-5% of cells) in 42% of cases, heterogeneous (staining in 6-30% of cells) in 27% of cases, and diffuse (> 30% of cells) in 31% of cases. Immunostaining for bcl-2 correlated with the presence of estrogen receptor (bcl-2 negative, 16% estrogen receptor positive versus bcl-2 positive, 88% estrogen receptor-positive; P < 0.001), with differentiation (bcl-2 negative, 62% poorly differentiated versus bcl-2 positive, 8% poorly differentiated; P < 0.001) and with better disease-free survival (bcl-2 negative, 82% recurrence versus bcl-2 positive, 28% recurrence; P = 0.0001; 52-mo mean follow-up). Immunostaining for p53 in greater than 5% of tumor cells was observed in 39% of cases and was more frequent in bcl-2-negative tumors (18/35, 51%) as opposed to bcl-2-positive tumors (14/46, 30%); P = NS. Disease recurrence correlated with p53 staining, which was observed in 51% of tumors that relapsed versus only 22% of tumors that did not recur. We conclude that bcl-2 is expressed in benign breast tissues that retain proliferative capacity and partial differentiation. Moreover, in neoplastic breast tissue, it is better correlated with a differentiated, "hormonally responsive," prognostically favorable phenotype than with disabled p53 gene function.     

A phase II trial of weekly infusional 5-fluorouracil in combination with low-dose leucovorin in patients with advanced colorectal cancer

We examined 59 breast cancers for p53 and bcl-2 protein expression by immunohistochemistry. The results were correlated with Ki-67 immunostaining. p53-negativity was noted in 40 cases and the remaining 19 tumours were p53-positive. Thirty-six tumours showed strong expression of bcl-2 and in 23 no staining for this protein was observed. We found statistically significant reverse correlation between expression of p53 and bcl-2 in majority of carcinomas: 31 cases were bcl-2 positive and p53-negative, and 14 tumours were bcl-2-negative and p53-positive. Six carcinomas showed no nuclear staining for Ki-67 and in the remaining 53 the percent of cancer cells positive for Ki-67 ranged from 1 to 60 (mean: 14.6). In these 53 cases we found that bcl-2-positive tumours were characterized by lower proliferation than bcl-2-negative tumours, the mean value of Ki-67 immunostaining being 10.7% and 23.0%, respectively. p53-negative tumours showed lower proliferation than p53-positive tumours: mean Ki-67 index was 10.2% and 23.9%, respectively. We conclude that immunohistochemically detected p53 and bcl-2 proteins show a significant inverse relationship in majority of breast carcinomas and their expression correlates with tumour proliferation (Ki-67 immunostaining).     

Carcinoma of the penis--appraisal of a modified tumour-staging system

OBJECTIVE: To determine the effect of double immunostaining in the differential diagnosis of the benign vs. malignant nature of breast lesions with fine needle aspiration results. STUDY DESIGN: The study group consisted of 26 samples aspirated from patients with borderline breast lesions. RESULTS: Direct immunostaining by means of monoclonal antibodies directed against individual intermediate filament proteins keratin 8 and 17 revealed that the percentage of K8+K17+ cells in material from patients with fibrocystic disease and fibroadenoma significantly exceeded that found in carcinoma specimens. The diagnoses were confirmed histologically. CONCLUSION: The quantitative method applied in the analysis of double-immunostained cytologic aspirates is recommended for the differential diagnosis of the benign vs. malignant nature of breast lesions in borderline cases.     

Pallidal activity during dystonia: somatosensory reorganisation and changes with severity

The molecular mechanisms by which advanced cases of cutaneous T cell lymphoma (CTCL) (mycosis fungoides/Sezary syndrome) undergo large cell transformation (LCT) and develop the morphologic appearance of a large cell lymphoma, are undefined. We used immunohistochemical analysis and polymerase chain reaction/single strand conformational polymorphism to examine whether p53 mutations are associated with disease progression and LCT in CTCL. p53 protein immunohistochemistry was performed on 37 paraffin embedded biopsies from 27 patients with CTCL; LCT was present in 15 biopsies. Overexpression of p53 protein was found in 11 of 37 CTCL biopsies including 10 of 15 biopsies (67%) with LCT in which p53 staining was predominantly seen in large transformed cells. In contrast, p53 immunostaining was found in only one of 22 CTCL biopsies without LCT (p < 0.0004). Serial biopsies revealed acquisition of p53 expression following LCT in two patients in whom initial diagnostic biopsies without LCT were p53 negative by immunostaining. All p53 protein positive biopsies were from advanced lesions (cutaneous tumors or extracutaneous sites); none of 12 patch/plaque stage CTCL biopsies demonstrated p53 staining. Polymerase chain reaction/single strand conformational polymorphism and sequencing analysis of p53 exons 4-8 was performed in 11 cases where frozen tissue was available. No mutations were detected in six cases positive for p53 protein expression. These results suggest overexpression of p53 protein in LCT and disease progression of CTCL by a mechanism other than p53 gene mutation, in most cases.     

A new whole-body exposure chamber for human skin and lung challenge experiments--the generation of wheat flour aerosols

The expression of BCL-2 protein was evaluated immunohistochemically in 23 intracystic papillary carcinomas (IPCs) of the breast. Twenty-two patients were female and one male, aged 49-90 years (median 72). Twenty-one cases had a benign behaviour, while two cases developed local recurrence. Of the 23 tumours, 19 (82%) were immunoreactive for BCL-2, the majority of positive carcinomas showing intense cytoplasmic staining of more than 50% neoplastic cells. The intensity of BCL-2 expression was significantly correlated with prognostic markers such as estrogen receptor (ER) positivity (p = 0.001), cathepsin D (CD) reactivity in the neoplastic cells (p = 0.001) and low growth fraction, evaluated by proliferating cell nuclear antigen (PCNA) immunostaining (p = 0.008). An inverse relationship was also found between BCL-2 and p53 protein (p = 0.001). Three cases of high grade (G3) IPC expressed p53, high PCNA index, and CD (the latter only in the stromal cells), but no immunostaining for BCL-2 and ER. Thus, absence of BCL-2 expression in high grade IPC was associated with ER-negative, rapidly proliferating and p53-positive immunophenotype. All high grade tumours showed invasion of the cystic wall. Local recurrence developed in one of these. The authors conclude that BCL-2 immunoreactivity in IPC is related with tumour grade and with a range of molecular markers of favourable prognosis such as ER positive status, CD expression in the neoplastic cells, and low PCNA index. These findings are consistent with the indolent clinical course and the very favourable prognosis of IPC of the breast.     

Moclobemide effects on prolactin plasma levels in healthy individuals: the hormonal increase induced by a single dose is maintained during a 4-week period of drug intake

AIMS: To examine the relation between the expression of p53 protein and the chaperone heat shock protein (hsp)72/73 in a population at high risk for gastric carcinoma, using single and double immunohistochemistry, and to compare the expression of these two proteins with clinicopathological features. METHODS: Monoclonal antibodies were used to investigate the expression of p53 protein and hsp72/73 in 46 human gastric carcinomas. A double immunohistochemical technique was used in cases that showed p53/hsp72/73 coexpression. RESULTS: p53 immunoreactivity was present in 11 tumours (24%), and hsp72/73 immunostaining was observed in 22 cases (48%). p53 expression was observed as nuclear staining in tumoral cells. hsp72/73 expression was demonstrated mainly as cytoplasmic staining, but six tumours also showed focal weak nuclear staining. Seven cases showed p53 and hsp72/73 coexpression with immunoreactivity for both proteins in the same neoplastic cells, three of them with focal areas of nuclear coexpression. p53 expression was seen more frequently in cases that showed a high intensity (+ + +) of hsp72/73 staining. No significant association was observed between the expression of the two proteins and clinicopathological features. CONCLUSIONS: More than half of our cases may have some impairment in p53 protein growth suppressive function, as a result of p53 gene alterations or complex formation. The positive correlation between p53 expression and intensity of hsp72/73 supports the postulate of a p53 regulating function for the chaperone hsp72/73. A high intensity of hsp72/73 immunohistochemical staining could be used as an indirect marker of p53 gene abnormalities.     

Diagnostic associations of p53 immunostaining in fine needle aspiration cytology of the breast

Duplicate cytospin preparations were made from 46 symptomatic breast fine needle aspirates. One of each pair was assigned to benign or malignant categories by one experienced observer as part of the "triple approach" patient assessment. The other was immunostained with DO7, a monoclonal antibody to recombinant p53 protein, and rated by another observer as positive or negative for nuclear staining, unaware of the cytodiagnosis. Positive controls included carcinomas known to have mutant p53, while negative controls were of the reagent substitution type. Of the 26 aspirates with a benign cytodiagnosis (verified by the triple approach), 23 were p53 protein-negative and three positive. Of the 20 with a malignant cytodiagnosis (histologically confirmed), six were p53 protein-negative and 14 positive (exact P < 0.0001). As a diagnostic test this would give 70% sensitivity and 88% specificity.     

Prevention of the major complications of diabetes mellitus. What is the evidence?]

AIMS: Although fine needle biopsy (FNB) is a well established diagnostic technique there continues to be controversy concerning its use in the pre-operative assessment of intraparotid masses. The purpose of this study was to evaluate the diagnostic accuracy, specificity and sensitivity of FNB in parotid tumours and consequently to asses its clinical value. METHODS: Over a 6-year period, 129 consecutive patients with parotid masses underwent pre-operative FNB evaluation and in 121 of these cases the cytological diagnosis was confirmed. RESULTS: Out of the 86 cases cytologically diagnosed as benign, two false negative results were obtained by FNB, whereas out of the 38 cytological diagnoses of malignant tumours one case was found histologically to be Warthin's tumour. In the FNB results of the two cases suspicious for malignancy, one was confirmed histologically as malignant. Three cases of FNB with inadequate material were found to be benign lesions. In this trail, the diagnostic accuracy of FNB was 96.7%, the specificity, 97.6% and the sensitivity, 95%. CONCLUSIONS: Our results show that FNB is a valuable examination technique in the pre-operative evaluation of parotid masses.     

The dysregulated podocyte phenotype: a novel concept in the pathogenesis of collapsing idiopathic focal segmental glomerulosclerosis and HIV-associated nephropathy

Immunocytochemical demonstration of metallothionein (MT) has been reported as a useful prognostic tool in human breast cancer. The aim of this study was to determine the immunohistochemical location of MT in canine mammary tumours and its possible correlation with the morphologic characteristics of these tumours. Surgical specimens from spontaneous malignant (n = 20) and benign mammary neoplasms (n = 20) were processed for routine histological examination and immunohistochemical study. An indirect immunoperoxidase technique, using monoclonal antibody E9 against horse MT was employed. Intensity of the stain, the percentage of immunoreactive tumour cells and immunohistochemical overexpression of MT was estimated for each case. Metallothionein over-expression, defined as those cases with more than 10% immunopositive cells, was detected in both benign and malignant mammary tumours. However, strong immunostaining intensity was seen in benign tumours, whereas in malignant tumours immunopositive cells stained weakly. Positive MT immunostaining occurred in neoplastic epithelial cells, and some chondrocytes present in mixed mammary tumours. However, staining intensity was variable in immunopositive cells. Differences in staining intensity between the primary malignant mammary tumour, tumour emboli and metastatic cells within a lymph node were also noted. Myoepithelial cells and connective tissue did not stain for MT. We concluded that metallothionein immunostaining cannot be used as a diagnostic or prognostic tool in canine mammary neoplasms. However, results of this study support the hypothesis that MT has a role in tumour proliferation and tumour progression.     

Does p53 immunostaining improve diagnostic accuracy in urine cytology?

The frequent change of the transitional cell carcinoma of the urinary tract accounts for the fact that cytological abnormalities in urinary specimens are often not sufficient to enable a definitive diagnosis of malignancy. The purpose of this work was to evaluate the possible use of p53 protein in increasing the diagnostic accuracy of urinary cytology. The expression of p53 was investigated by immunocytochemistry in two groups of urinary specimens, one cytologically positive and the other cytologically negative for cancer. Immunostaining was carried out using a monoclonal antibody to p53. In the positive group, in which bladder cancer was confirmed by cystoscopy and biopsy (31 cases), positive reaction for p53 was found in 55% of the cases (17 cases). In the negative group (92 cases), presence of cancer was histologically ascertained in 64 cases and in this group 15 cases (23.4%) showed positive p53 staining. In the remaining 28 cases of this group, where TCC was not present, 7 cases showed p53 positivity in non-neoplastic urothelial cells. This result shows that, while immunocytochemical detection of p53 in urinary specimens may be used for prognostic evaluation of patients with bladder cancer, it does not contribute to the diagnostic accuracy in cases with morphologically inconclusive or negative cytology. The sensitivity and specificity of the method in detecting bladder carcinoma were 23.5 and 75%, respectively.     

Benign and malignant cells in effusions: diagnostic value of image DNA cytometry in comparison to cytological analysis

Identifying tumor cells in body cavity fluids reliably is a well-known diagnostic problem. Since cytometric quantitation of nuclear DNA content appears to be a promising new tool in the diagnosis and prognostic evaluation of many solid human tumors, we examined its validity in detecting malignant cells in cytologically positive effusions. For this purpose, image DNA cytometric measurements, including the evaluation of DNA-ploidy and the calculation of the DNA index (DI), were performed in 80 body cavity fluids. The results were correlated with cytology, clinical course and final histological diagnoses. We used aneuploidy, as shown by interactive image DNA cytometry, as a marker for the malignancy of cells that occur in body cavity fluids with a 100% specificity and 94.8% sensitivity. Cytological investigation showed a 92.3% specificity and 95.4% sensitivity. Combining both methods raised the specificity to 100% and the sensitivity to 98.5% and had a positive predictive value of 100% and a negative predictive value of 93.8%. The DNA-index (DI) was significantly higher in malignant effusions than in benign effusions: 1.5 +/- 0.74 (mean +/- SD) versus 1.11 +/- 0.26 (p < 0.05). Along with the difficult cytological evaluation of malignant cells in body cavity fluids, image DNA cytometry can be a helpful additional method for evaluating these cells. Combining the two techniques results in a highly specific and sensitive prediction of malignant cells. We, therefore, suggest using these methods for the reliable identification of tumor cells in effusions.     

Defective proximal tubule lysosomal acidification by Bence Jones proteins. An immunoelectron microscopy study

AIMS: To determine their significance, we examined the expression pattern of the four epidermal growth factor receptor (EGFR) family members as well as the phosphotyrosine kinase activity in breast tumour tissues. METHODS AND RESULTS: Fifty-three malignant breast tumours, four breast cancer cell lines, and 10 benign breast tumours were investigated. Fifty-three per cent (28/53) of the malignant tumours expressed EGFR protein, and the majority of these positive tumours were strongly positive. Eighty per cent (8/10) of the benign tumours also expressed EGFR protein, but all in a lower or moderate level. An association between EGFR expression and increasing malignancy grade was found in the group of infiltrating ductal carcinomas. Of the malignant tumours, 35.8% (19/53) expressed c-erbB-2 protein and 17% (9/53) c-erbB-3 protein, while no expression of c-erbB-2 and c-erbB-3 proteins was found in the benign tumours. Contrary to previous reports, we observed c-erbB-4 receptor protein to be less expressed in the malignant breast tumours. The 'normal' breast epithelial cells adjacent to the malignant tumours and the benign tumours demonstrated intensified membrane staining for c-erbB-4, while a number of the malignant tumours demonstrated a weak cytoplasmic staining or were negative. However, several malignant tumours with strong membrane staining for the c-erbB-4 protein were also found. No simple association between the expression of the four receptors and phosphotyrosine kinase activity was found. CONCLUSION: Our study has revealed a complex expression pattern of the EGFR family members in breast tumour cells. While the data about EGFR, c-erbB-2, c-erbB-3 and phosphotyrosine are largely in line with what has been reported, we found the c-erbB-4 protein expression to be decreased in the malignant tumours.     

P53 protein expression and DNA ploidy in common epithelial tumors of the ovary

OBJECTIVE: To investigate p53 protein expression and DNA content in imprints from surgical biopsies of common epithelial tumors of the ovary. STUDY DESIGN: The study was based on 60 cases of epithelial tumors of the ovary (15 benign, 3 border-line and 42 malignant). For the demonstration of p53 protein, immunocytochemical staining with the avidin-extravidin technique was performed using monoclonal antibody p53 DO-7. DNA content was measured by image cytometry after Feulgen staining. RESULTS: There was a strong correlation between p53 expression and aneuploidy, with the difference between diploid and aneuploid tumors statistically significant (P < .001). A correlation was found between DNA ploidy, histologic grade and clinical stage (P < .001 and P < .05), respectively. There was no correlation between DNA ploidy and histologic type (P = .89). No correlation was observed between p53 protein expression and grade or clinical stage of the tumors. Nevertheless, a correlation of p53 expression between early (I, II) and advanced stages (III, IV) (P < .05) was observed. All benign and borderline tumors were diploid and did not express p53 protein. CONCLUSION: The results of the present study and the data in the literature stress the value of p53 expression and DNA ploidy in assessing the malignant potential of common epithelial ovarian cancers. However, the clinical application of these data requires further study.     

Expression of DNA topoisomerase I, DNA topoisomerase II-alpha, and p53 in metastatic malignant melanoma

New anticancer drugs that target DNA topoisomerase I (topo I) are showing activity against a wide variety of solid human neoplasms. These drugs work by a novel mechanism of action and cause topo I-mediated DNA breaks. These DNA breaks become lethal in cycling cells when they interact with the replication fork. Because of the challenges in treating metastatic malignant melanoma, we performed an immunohistochemical study of this group of neoplasms to search for the presence of molecular markers that might indicate tumor response to topo I active drugs. Using a new immunohistochemical stain for topo I, we found elevation of this protein in 10 of 24 cases (41.6%) of metastatic malignant melanoma. The metastatic tumors that showed increased expression of topo I (2+ or 3+) had statistically significant higher proliferation indices, measured by immunohistochemical staining for DNA topo II-alpha, than did metastatic lesions with no detectable topo I expression. The average topo II-alpha index of metastatic melanomas with 2+ topo I expression was 45.1 (SD = 17.9) and with 3+ topo I expression was 52.3 (SD = 32.5). These values were found to be statistically different (P = .05) than the average topo II-alpha index of 18.9 (SD = 17.7) found for metastatic melanomas without detectable topo I immunostaining. Immunohistochemical staining for p53 suggested abnormal p53 function in 6 of the 10 melanomas (60%), which showed elevations of topo I (2 to 3+ topo I immunostaining) but normal p53 function in all 14 metastatic lesions that showed normal topo I expression.