p53 expression in oat and non-oat small cell lung carcinomas: correlations with proliferating cell nuclear antigen.

AIMS--To investigate the immunohistochemical expression of p53 protein in small cell lung carcinoma (SCLC), comparing it with that in non-small cell carcinoma (NSCLC); and to evaluate the correlation between p53 and proliferating cell nuclear antigen (PCNA) expression as well as between p53 and PCNA expression and survival. METHODS--Paraffin wax embedded tissues from 61 cases of primary lung carcinoma were stained for p53 protein and PCNA using the monoclonal antibodies 1801 and PC-10, respectively, in a standard avidin-biotin immunoperoxidase method. RESULTS--Of the 61 lung carcinomas 35 (57%) were positive for p53 (range 1% to 90%). Ninety percent of the non-oat SCLC contained positive cells and the labelling index (LI) was significantly higher than that of the oat SCLC (p < 0.001). SLCC also displayed a higher p53 LI than NSCLC (p < 0.01); no difference was found between squamous carcinoma, adenocarcinoma, and oat cell carcinoma. A p53 LI of greater than 1% tended to be associated with nodal metastases (p < 0.05), and p53 expression in node positive tumours as well as in oat cell carcinomas was indicative of poorer survival (p < 0.01 and p < 0.1, respectively). A p53 Li of greater than 60% was a negative prognostic factor in non-oat SCLC (p < 0.05). PCNA LI was highest in non-oat SCLC and lowest in NSCLC; oat cell carcinomas had a mean LI intermediate between NSCLC and non-oat SCLC (NSCLC v oat cell carcinoma p < 0.05 and oat cell v non-oat cell carcinomas p < 0.01). A PCNA LI was not correlated with nodal metastases or survival, but there was a significant positive correlation between PCNA LI and p53 LI (rs = 0.484, p < 0.001). CONCLUSIONS--p53 and PCNA expression differ substantially among the various types of lung carcinomas. Substantial differences were also found between oat and non-oat types of SCLC, indicating that SCLC is heterogeneous as far as proliferation rate and altered p53 expression is concerned. p53 seems to be of some prognostic value. The relation between PCNA and p53 expression indicates that the PCNA gene is slightly upregulated by p53.     

Correlation between histological grade, MIB-1, p53, and recurrence in 69 completely resected primary intracranial meningiomas with a 6 year mean follow-up

Sixty-nine intracranial, totally excised meningiomas were immunostained for MIB-1 and p53 protein expression. According to the 1993 WHO criteria, revised by Perry et al., the 69 meningiomas were classified into: grade I = 54 benign meningiomas, grade II = 10 atypical meningiomas, grade III = 5 malignant meningiomas. The patients were followed until death or for an average of 6.7 years. The 69 meningiomas were divided into two groups, according to the absence (n = 42) or presence (n = 27) of recurrences. In the last group we included 3 patients who died of meningioma recurrence. According to the percentage of MIB-1 positively stained cells, meningiomas were divided into three groups: <1% (n = 36), 1-10% (n = 28), >10% (n = 5). We found the MIB-1 labeling index (LI) <1% in 33 grade I (61%) and in 3 grade II (30%) meningiomas. On the other hand, 7 grade II (70%) and all grade III (100%) meningiomas presented a MIB-1 LI >1%. Correlation between histological grade and MIB-1 LI was statistically significant (p = 0.0006). The correlation between MIB-1 LI and follow-up was also highly significant (p < 0.001): the majority of meningiomas which did not recur (32/42 equal to 76%) were characterized by a low (<1%) MIB-1 LI. In the recurrence group MIB-1 LI was significantly higher than in the disease-free patients' group. Moreover, MIB-1 appeared to be a prognostic parameter not strongly related to the histological grade. In fact, it was significantly higher in recurrent histologically benign meningiomas, as compared with benign meningiomas without recurrence (p = 0.0006). Positive p53 protein expression (>1%) was shown in 26/45 meningiomas (57%), with an LI of 1-10% in 18 (40%) and an LI of >10% in 8 (17%) meningiomas. Although the p53 LI tended to be higher in atypical and malignant meningiomas, no significant correlation was found between the p53 expression and the recurrence (p = 0.05). The authors conclude that quantitative MIB-1 labeling is a useful technique in the routine diagnostic assessment of meningiomas, and helpful in obtaining more information about prognosis and thereby in planning the most suitable treatment.     

p53, c-myc p62 and proliferating cell nuclear antigen (PCNA) expression in non-Hodgkin's lymphomas.

AIMS--To investigate the immunohistochemical expression of p53 protein in non-Hodgkin''s lymphomas (NHL) and its relation to that of c-myc p62 oncoprotein and proliferating cell nuclear antigen (PCNA). METHODS--Paraffin wax embedded tissue from 90 non-Hodgkin''s lymphomas (72 B cell and 18 T cell) was stained immunohistochemically for p53 protein, c-myc p62 oncoprotein, and PCNA using the monoclonal antibodies DO7, c-myc 1-9 E10, and PC-10, respectively. RESULTS--Of the non-Hodgkin''s lymphomas studied, 55 (61%) stained positively for p53 protein. The proportion of positive cases increased from low grade non-Hodgkin''s lymphoma and was higher in tumours of T cell origin. The percentage of positive cells (labelling index or LI) was significantly lower in low grade non-Hodgkin''s lymphoma, but no difference was established between intermediate and high grade non-Hodgkin''s lymphoma. In a large proportion of low grade non-Hodgkin''s lymphoma the LI was below 1%. c-myc p62 immunoreactivity was identified in all cases. A significant positive correlation was established between p53 LI and c-myc p62 LI (rs = 0.453) as well as between p53 LI and PCNA LI (rs = 0.338). CONCLUSIONS--p53 immunoreactivity was present in about half the cases of non-Hodgkin''s lymphoma and was related to the grade of malignancy and possibly to the B or T cell origin of the tumour. It was also associated with the proliferation state as expressed by PCNA LI and c-myc p62 expression, indicating that the expression of these three cell cycle-related genes might be interrelated.     

Expression of cyclin D1, Ki-67 and PCNA in non-small cell lung cancer: prognostic significance and comparison with p53 and bcl-2

Uncontrolled cell proliferation is the hallmark of malignant tumours. Thus, the proliferative potential of tumour cells is an important prognostic factor. However, evaluation of the prognostic significance of the expression of proteins involved in regulation of cell proliferation remains controversial. In the present study, expression of Ki-67, PCNA and cyclin D1 was estimated in a group of 89 surgically resected non-small cell lung carcinomas using immunohistochemistry. The results were compared with expression of bcl-2 and p53 and with clinicopathological parameters including patients' survival. Ki-67 and PCNA were found to be moderately and highly expressed in 39% and 44% of the tumours, respectively. There was a strong correlation between Ki67 and PCNA expression. Forty five of 88 tumours (51%) showed overexpression of cyclin D1. Surprisingly, cyclin D1 was mainly localized in the cytoplasm and only a small group of tumours (9/88, 10%) showed nuclear staining as well. Bcl-2 and p53 expression was observed in 69% and 30% of the tumours, respectively. All these markers were found to be independent of clinicopathological parameters, except for Ki-67 and bcl-2 expression, which was associated with squamous cell carcinomas. It is concluded that none of the markers that were studied can be used as an independent prognostic factor, whereas the following combinations of markers may have favourable prognostic value: p53 positivity and low Ki-67 expression, p53 positivity and lack of cyclin D1 expression, bcl-2 positivity and low Ki-67 expression, and lack of cyclin D1 expression and low Ki-67 expression.     

Immunohistochemical analysis of bcl-2 and p53 expression in breast carcinomas: their correlation with Ki-67 growth fraction

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).     

Prognostic value of tumour associated antigen immunoreactivity and apoptosis in cerebral glioblastomas: an analysis of 168 cases

AIMS: To evaluate a possible association between clinical outcome in patients with glioblastoma and expression of some immunohistochemical variables and apoptosis. METHODS: 168 selected patients with cerebral glioblastomas were studied retrospectively. Tumour specimens were examined immunohistochemically with antibodies to proliferating cell nuclear antigen (PCNA), p53, bcl-2, and epidermal growth factor receptor (EGFR) to detect the intracellular receptor domain. Apoptosis was detected by in situ end labelling. Multivariate analysis was performed using the Cox proportional hazard model. RESULTS: On univariate analysis the PCNA labelling index, immunoexpression of EGFR, and the apoptotic index were significantly related to glioblastoma outcome. Survival time was reduced as PCNA labelling index increased and apoptotic index decreased (p = 0.0073 and p = 0.00031, respectively). Survival time in patients with EGFR positive tumours was found to be reduced (p = 0.00024). Multivariate analysis showed independent prognostic value for the EGFR positivity and apoptotic index only (p = 0.0053 and p = 0.0039, respectively). There was no association between clinical outcome of glioblastoma and p53 or bcl-2 immunostaining. CONCLUSIONS: EGFR immunoreactivity and apoptotic index were found to be useful for assessing prognosis of individual glioblastomas but it seems unlikely that p53 and bcl-2 immunohistochemistry will be of value in determining survival in such patients.     

DNA topoisomerase IIα expression correlates with cell proliferation but not with recurrence in intracranial meningiomas

AIMS: To assess the value of topoisomerase IIalpha (TopoIIalpha) as a novel proliferation-associated molecule, by correlating its immunohistochemical expression with Ki67 (MIB-1), cell proliferating cell nuclear antigen (PCNA) and mitotic index in meningiomas. Furthermore, to investigate its relation to standard clinicopathological parameters and patients' outcome. METHODS AND RESULTS: This retrospective study comprised a consecutive series of 57 patients with primary intracranial benign and atypical meningiomas. Six tumours recurred (10.5%) following complete surgical resection, within a follow-up period ranging from 21 to 108 months (median 60 months). Archival formalin-fixed paraffin-embedded sections were stained with standard immunohistochemical methods. The lower proliferation indices were obtained with TopoIIalpha and the higher ones with PCNA. TopoIIalpha labelling index (LI) ranged from 0.1% to 10% (median 0.5%) and, along with Ki67 and PCNA LI, increased with malignancy grade (P=0.049, P=0.045 and P < 0.001, respectively), displaying though a significant overlapping between grades. A significant positive correlation was shown between TopoIIalpha and Ki67 (P < 0.001) or PCNA (P=0.032). In univariate and multivariate survival analysis, TopoIIalpha failed to predict meningioma recurrence and did not affect disease-free survival. Only tumour size and Ki67 LI provided significant prognostic information in this regard. CONCLUSIONS: TopoIIalpha expression may be useful as a novel proliferation marker in meningiomas, presenting several advantages over the markers currently in use, notably providing a better estimate of the number of cycling cells and a more uniform nuclear staining pattern. However, it fails to discriminate between benign and atypical neoplasms and does not provide prognostic information beyond that obtained by Ki67.     

EGFR and p53 expression and proliferative activity in parathyroid adenomas; an immunohistochemical study

EGFR (epidermal growth factor receptor), p53, and proliferative markers provide some clues as to the formation of several tumours. In this study the mechanism of the genesis of parathyroid adenomas was investigated using immunohistochemistry. Sections of parathyroid adenomas from 12 cases were stained using PCNA (proliferating cell nuclear antigen), EGFR, and p53 immunohistochemistry. Correlations between PCNA LI (labelling index), EGFR expression, p53 expression, age, serum parathormone, Ca and P levels, and tumour diameter were investigated. PCNA LI was 45.8+/-33.1 (mean+/-standard deviation) and all the cases were somewhat positive. Five cases (41.67 %) were EGFR positive. Maximum 10 % of the cells were positive in these cases. All the cases were p53 negative. There was a correlation between PCNA LI and serum parathormone level (r=0.607, p=0.036). According to these results, parathormone synthesis is high when the proliferative activity of parathyroid adenoma is high. Four of the five EGFR-positive patients were below 35 years of age. These data may indicate that formation of parathyroid adenoma in young patients is related to a mechanism involving EGFR. Absence of p53 expression suggests that p53 mutation is not a common component of parathyroid adenomas.     

Apoptotic activity and bcl-2 immunoreactivity in meningiomas. Association with grade and outcome

We retrospectively evaluated 90 meningiomas for bcl-2 expression, apoptosis counts (per 10 high-power fields [HPF]), MIB-1 labeling indices (LI), and mitosis counts (per 10 HPF). Characteristics were as follows: 37 low-grade (benign) meningiomas: mean apoptosis count, 1.2; MIB-1 LI, 1.0; mitosis count, 0.1; and bcl-2 positivity, 40%; 29 atypical meningiomas: apoptosis count, 3.3; MIB-1 LI, 5.5; mitosis count, 2.2; and bcl-2 positivity, 62%; 24 malignant meningiomas: apoptosis count, 6.5; MIB-1 LI, 12.0; mitosis count, 6.0; and bcl-2 positivity, 67%. By univariate analysis, MIB-1 LI, apoptosis and mitosis counts, and tumor grade were associated significantly with death due to tumor; by multivariate analysis, only mitosis count was independently associated with death due to tumor. We compared similar data for 27 patients with nonrecurrent tumors and 32 patients with recurrent meningiomas. Histologic sections from the initially resected tumor and from the most recent recurrence were reviewed. Only the apoptosis count was significantly higher by univariate analysis in the initial resection specimens from tumors that ultimately recurred vs nonrecurrent tumors. Expression of bcl-2, MIB-1 LI, and mitosis count did not correlate with recurrence. By multivariate analysis, only extent of surgical resection was associated significantly with tumor recurrence. Although bcl-2 immunostaining was not associated statistically with outcome, bcl-2 positivity was more common in atypical and malignant meningiomas than in low-grade tumors.     

Proliferation marker MIB-1 correlates well with proliferative activity evaluated by BrdU in breast cancer: An immunohistochemical study including correlation with PCNA, p53, c-erbB-2 and estrogen receptor status

The proliferative activity of 30 cases of non-treated invasive ductal breast carcinoma was evaluated by bromodeoxyuri-dine (BrdU), proliferation marker (MIB-1) and proliferating cell nuclear antigen (PCNA), and the relation between these proliferation markers and histologlcal subtype and histolog-ical grade were investigated. In addition, the association of these proliferation markers with overexpression of p53 protein, c-erbB-2 oncoprotein, estrogen receptor (ER) status and clinicopathologic findings were also examined. The BrdU labeling index (LI), MIB-1 score and PCNA labeling rate (LR) correlated with the histological grade. However, there was no statistical difference in proliferative activity among the histological subtypes. A linear strong correlation was demonstrated between BrdU Li and MIB-1 score (r=0.732). Significant correlation was also found between BrdU LI and PCNA LR (r=0.446); however, the relation between MIB-1 score and PCNA LR was weak. BrdU LI and MIB-1 score correlated positively with tumor size, TNM stage and over-expression of p53, and negatively with the presence of ER. PCNA LR correlated only with p53. These results indicate that MIB-1 is closely associated with BrdU in clinicopathologic findings and is a more useful tool for evaluating cell proliferation than PCNA. However, it will be necessary to consider the clinical significance of MIB-1 immunohisto-chemistry cautiously until further widespread clinical and pathological studies are performed.     

DETECTION OF p53 AND bcl-2 PROTEIN IN CARCINOMA OF THE RENAL PELVIS AND URETER INCLUDING DYSPLASIA

Ninety-four patients with transitional cell carcinoma (TCC) of the renal pelvis and ureter, including dysplastic lesions, were studied for p53 and bcl-2 protein expression by immunohistochemistry. Twenty-one patients were also studied for p53 gene mutations by direct sequencing and for bcl-2 gene rearrangement by Southern blot analysis. Overexpressed p53 protein was detected in 26 cases (27·7 per cent). bcl-2 immunostaining was observed in 21 tumours (22·3 per cent), including four cases with labelling for p53. Furthermore, the dysplastic lesions surrounding 19 p53-positive tumours also stained for p53. bcl-2 expression was also detected frequently in dysplastic lesions adjacent to 14 bcl-2-positive TCCs. Positive reactions of dysplastic lesions were also found adjacent to 37 bcl-2-negative tumours. p53 point mutation was detected in 6 of 21 cases. Five of the six cases were positive for p53 protein. bcl-2 positivity was detected in 3 of 21 tumours, without bcl-2 gene rearrangements in the major breakpoint region. Overexpressed p53 protein was frequently detected in both high-grade ( P <0·05) and invasive tumours ( P <0·05). In three cases of p53-positive non-papillary invasive tumours, bcl-2 was found in non-invasive portions, but was not present in invasive areas. These findings suggest that overexpression (mutation) of p53 and/or bcl-2 protein may be early events in tumourigenesis and that p53 alterations in particular are essential for the maintenance of a malignant phenotype in tumour development.     

Expression of P-glycoprotein in hepatocellular carcinoma: a potential marker of prognosis.

AIMS: (1) To investigate the immunohistochemical expression of the multidrug resistance gene (MDR1) product P-glycoprotein in histological samples from 31 hepatocellular carcinomas (HCCs); and (2) to correlate the results with cell proliferation, p53 expression, the disease-free interval, and cumulative patient survival. METHODS: C219 (a monoclonal antibody), CM-1 (a polyclonal rabbit anti-human antibody) and PC10 (a monoclonal mouse anti-human antibody) were used to detect expression of P-glycoprotein, p53 and proliferating cell nuclear antigen (PCNA), respectively, by means of the avidin-biotin peroxidase method. RESULTS: Membrane bound positivity for P-glycoprotein was observed in 20 (65%) of the 31 HCCs. Cytoplasmic globular positivity was also seen in some cases. There were no significant associations between expression of P-glycoprotein and cell proliferation (determined by PCNA immunoexpression and the mitotic count), or p53 expression. Patients with P-glycoprotein positive tumours had a shorter disease-free interval than those with P-glycoprotein negative tumours, and also had a shorter survival time. There was no difference in survival between P-glycoprotein positive patients who had or had not received chemotherapy, suggesting that chemotherapy (mainly mitomycin-C) did not affect survival in these patients. CONCLUSIONS: Expression of P-glycoprotein in HCCs is associated with a shorter disease-free interval and shorter survival time. As expression of P-glycoprotein was not associated with cell proliferation or expression of p53, its effect on disease progression and survival seems to be independent of these factors.     

p53 Protein,PCNA staining,and DNA content in follicular neoplasms of the thyroid gland

Forty-nine follicular adenomas and 11 follicular carcinomas of the thyroid were investigated by immuno-histochemistry for the expression of p53 protein and proliferating cell nuclear antigen (PCNA). The DNA ploidy and the S-phase fraction (SPF) of the neoplasms were analysed by flow cytometry. Twelve adenomas (24 per cent) and six carcinomas (55 per cent) were DNA non-diploid (P=0·07). The carcinomas had a higher proliferation rate than the adenomas when assessed either by SPF size (median 9·9 per cent vs. 2·9 per cent, P=0·0003) or by PCNA staining intensity (P<0·0001). Some scattered nuclei in two (4 per cent) adenomas and in three (27 per cent) carcinomas stained positively for p53 (P=0·04). The two adenomas with positive staining for p53 were subserially sectioned, but no signs of invasion were found; both patients are alive and well 6 and 7 years after surgery. One of the two adenomas showing positive p53 nuclear staining was DNA aneuploid, and both were positive in PCNA staining, but their SPFs were low (2·1 and 3·3 per cent). We conclude that p53 protein expression is not confined to follicular carcinomas; scattered p53-positive cells may also be present in histologically and clinically benign follicular adenomas. Because both follicular adenomas and carcinomas may be DNA aneuploid and their SPF and PCNA staining distributions overlap, the distinction between follicular adenoma and carcinoma should still be based on histological criteria.     

Different proliferative patterns characterize different preinvasive breast lesions

The study of cell-cycle associated proteins Ki-67/MIB-1, bcl-2 and p53 could clarify some features regarding the early phases of neoplastic progression in the breast. An extensive immunohistochemical study was carried out of the expression of these markers in all kinds of preinvasive breast lesions and their collateral normal parenchyma, a type of analysis not previously reported. The specimens were 35 florid ductal hyperplasias (FDHs), 8 atypical ductal hyperplasias (ADHs), 12 well-differentiated intraductal carcinomas (WDICs), 20 intermediately differentiated intraductal carcinomas (IDICs), 14 poorly differentiated intraductal carcinomas (PDICs), 12 atypical lobular hyperplasias (ALHs), 12 type-A lobular carcinomas in situ (LCIS), 150 normal small-size ducts and 365 lobules. All FDHs, ADHs, WDICs, and lobular lesions showed low proliferation (Ki-67/MIB-1), bcl-2 positivity, and p53 negativity; all PDICs expressed high proliferation, while 85 per cent and 7 per cent were p53 and bcl-2 positive respectively; IDICs showed high proliferation (50 per cent), bcl-2 expression (70 per cent), and p53 positivity (30 per cent), but no correlation between the expression of these markers was observed. Independent of the type of collateral lesion and age of the patient, 90 per cent and 10 per cent of small ducts/lobules showed low and high proliferation and diffuse and low bcl-2 expression respectively; no p53 positivity was observed. The modulation of cell proliferation and apoptosis control in ductal lesions could be the expression of a progression from hyperplasia/WDIC to PDIC, in which IDICs represent the link, owing to their immunoprofile. An alternative purely speculative hypothesis is that the different immunoprofile of the preinvasive lesions reflects their different origin in normal breast parenchyma. Low proliferative or bcl-2 positive lobules could be the site of origin of the lesions maintaining this phenotype, namely FDHs, ADHs, WDICs and lobular lesions, while highly proliferative or bcl-2 negative lobules could be the site in which PDICs develop. Consequently, preinvasive breast lesions could express a different regulation of apoptosis control and proliferative activity from the very beginning, rather than a modulation during neoplastic progression. Copyright © 1999 John Wiley & Sons, Ltd.     

An evaluation of six antibodies for immunohistochemistry of mutant p53 gene product in archival colorectal neoplasms

Immunohistochemical detection of intranuclear p53 gene product may indicate mutation of the p53 suppressor gene on chromosome 17p. We used six commercially available antibodies for p53 immunohistochemistry on 19 archival colorectal neoplasms and compared the results with the mutation status of the p53 gene and 17p allelic deletion status. By Friedman's ranking analysis, use of mouse monoclonal antibody DO7 with Target Unmasking Fluid (TUF) for antigen retrieval was the most sensitive and specific procedure (P<0·0001). Six of 7 cases with high expression (p53 Labeling Index >30 per cent using a CAS 200 image analyser) had p53 mutation. Of seven tumours without expression (LI < 1 per cent), six had no mutation and one had a truncating mutation which prohibited nuclear localization of gene product. The low expression group (1 per cent < LI <30 per cent, n = 5) consisted of three tumours without and two tumours with mutation. The sensitivity of high expression with the DO7–TUF method for p53 gene mutation was 67 per cent with specificity of 90 per cent, predictive value of a positive of 86 per cent, predictive value of a negative of 75 per cent, and efficiency of 79 per cent. This study suggests that immunohistochemistry is valuable for assessing p53 gene mutations in colorectal neoplasms, but further study is needed to elucidate the precise link between immunohistochemistry and molecular genetic alterations.     

Apoptosis in epithelial ovarian tumors

It is now recognized that apoptosis plays an important role in the pathogenesis of tumors. This study evaluated the extent of apoptosis in different grades of ovarian tumors and correlated it with the expression of apoptosis regulatory genes, p53 and bcl-2 and with the total proliferative compartment of the tumor defined by the expression of the proliferating cell nuclear antigen (PCNA). Apoptosis was evaluated by the TUNEL (Tdt-mediated dUTP biotin nick end labelling) assay. Expressions of p53, bcl-2 and PCNA were analyzed by immunohistochemistry. A negative correlation was observed between the expression of bcl-2 and the extent of apoptosis (r = -0.3336, p = 0.019). P53 accumulation directly correlated with the extent of apoptosis (r = 0.485, p = 0.00041). The labelling index of PCNA also showed correlation with expression of p53 (r = 0.49, p = 0.00000). Apoptosis was significantly higher in poorly differentiated tumors when compared to the well- and moderately-differentiated tumors (r = 0.49152, p = 0.00034). Such poorly-differentiated tumors also showed high p53 overexpression and loss of bcl-2 expression. The present study thus provides evidence that dysregulation of apoptosis and its regulatory genes is associated with increasing malignant potential and may thus contribute to the pathogenesis of ovarian tumors.     

乳腺癌细胞凋亡、增殖与相关基因表达、突变的关系

目的:研究乳腺癌细胞凋亡、细胞增殖及相关基因表达、突变的关系,为乳腺癌细胞凋亡、细胞增殖失衡的基因调控机制提供依据。方法:分别应用TUNEL法、免疫组化S-P法和PCR-SSCP法检测54例乳腺癌标本凋亡指数(AI)和增殖指数(MI),Bcl-2、p53、c-erbB-2、PCNA、Ki67、TopoⅡ蛋白表达和p53基因突变。结果:54例乳腺癌AI平均9.40±3.78,MI平均5.96±2.36,AI与MI呈显著正相关(r=0.46,P＜0.01)。Bcl-2、PCNA、Ki67、TopoⅡ表达与AI、MI均呈显著正相关(P＜0.01)。p53表达、c-erbB-2表达、p53突变与MI呈显著正相关(P＜0.01)。p53基因突变类型与AI呈显著相关(P＜0.05)。结论:乳腺癌细胞凋亡、增殖失衡与相关基因异常表达、突变有关。     

P 53 and PCNA in Non Hodgkin's lymphoma--an immunohistochemical evaluation

P 53 positivity and PCNA labelling index were studied in 50 cases of node based Non Hodgkin's lymphomas, P 53 positivity was observed in a spectrum of these disorders, suggesting that P 53 mutations play a role in the genesis of these tumours. P 53 positivity incresed from low through intermediate to high grade tumours and thus may be of prognostic value in these lesions. PCNA labelling index (LI) was higher in high grade tumours. P 53 and PCNA immunoreactivity showed a relationship in that PCNA LI was seen to be more than 30% in P 53 positive tumours. P 53 positivity appears to be related to the subtype and proliferation rate of NHL.     

Apoptosis is associated with atypical or malignant change in meningiomas. An in situ labelling and immunohistochemical study

Aims : Although necrosis is an important phenomenon with implications for grading and prognostication in meningiomas, the alternate form of cell death, apoptosis, has not been extensively studied. In this series, we aimed to determine whether apoptosis in meningiomas correlated with histological types and grading. We also looked for a relationship between expression of apoptosis-related genes bcl-2 , p53 , c-myc and apoptosis in meningiomas.  

Methods and results

Fifty-one meningiomas of diverse histological subtypes and grades were investigated with in-situ end-labelling of DNA fragments as well as immunohistochemical analysis of three apoptosis-related genes: p53 , bcl-2 and c-myc . Our results showed that the apoptosis index was significantly higher in high-grade meningiomas (0.12%, n  = 12) in than the benign meningiomas (0.023%, n  = 39) ( P  = 0.001) but there was no difference among the different histological subtypes of the benign meningiomas ( P  = 0.125). There is no obvious relationship between p53, bcl-2 and c-myc staining and apoptosis index in this group of meningiomas.  

Conclusion

We conclude that apoptosis is an important phenomenon in meningiomas and that it is associated with atypical or malignant changes in meningiomas. Apoptosis in meningiomas has no clearcut relationship with expression of p53 , bcl-2 and c-myc .     

Immunohistochemical analysis of bcl-2 expression in transitional cell carcinoma of the bladder.

AIMS: To evaluate the expression of bcl-2 in transitional cell carcinoma (TCC) of the bladder; to compare bcl-2 expression with clinicopathological findings, p53 immunoreactivity, proliferating cell nuclear antigen (PCNA) expression, 2c deviation index (2cDI), 5c exceeding rate (5cER), and the mean nuclear area (MNA). METHODS: Cystectomy specimens from 77 patients with untreated, non-metastatic TCC of the bladder were studied. Expression of bcl-2, p53 and PCNA was detected immunohistochemically using the following monoclonal antibodies: bcl-2/124, DO-7 and PC10, respectively. Nuclear DNA content was analysed using static cytometry. RESULTS: Bcl-2 was expressed in 19 (24.7%) of 77 TCCs and in 74 (96.1%) of 77 normal samples of transitional epithelium (taken from normal tissue adjacent to the tumour in each case). In all cases, bcl-2 immunoreactivity was more intense in normal transitional epithelium than in TCC. In normal transitional epitehlium and superficial TCC bcl-2 immunoreactivity was observed at the basal layer, and not at the invasive front. Bcl-2 immunoreactivity was invesely correlated with histological grade and p53 immunoreactivity, and was not correlated with the pT category, disease progression, PCNA expression, 2cDI, 5cER, and the MNA. No significant correlation was found between bcl-2 expression and overall survival. CONCLUSIONS: Bcl-2 expression in TCC of the bladder seems to be associated with a less aggressive phenotype and does not play an important role in tumour progression.