Mean Proliferating Cell Nuclear Antigen Research Articles

Expression of proliferating cell nuclear antigen and Ki-67 in renal cell carcinoma in eastern Indian patients

Background: Several molecular markers play important role in development and prognosis of renal cell carcinoma (RCC). Proliferating cell nuclear antigen (PCNA) and Ki-67 are such kind of molecular markers which may have prognostic significance in RCC and need to be studied about. Estimation of proliferation index by immunohistochemical expression analysis of PCNA and Ki-67 at different clinical stages of RCC samples and correlations of expression of the genes with different clinicopathological parameters between tumour tissue cells and adjacent normal tissue cells were the objectives.Methods: Thirty two patients of RCC who had been operated at one tertiary care institute of eastern India were taken for the study. Histopathological and immunohistochemistry analysis of PCNA and Ki-67 from tumour tissue and normal tissue were done. Patients who received radiotherapy, chemotherapy etc. before operation and who had benign tumours of the kidney in histopathological examination were excluded from the study.Results: Mean PCNA expression in normal renal tissue is 4.54%; whereas the clear cell RCC, papillary RCC and chromophobe RCC showed 49.81%, 50.75% and 66.50% of mean PCNA expression respectively. Mean expression of Ki-67 in normal tissues was 1.75%. Whereas the clear cell RCC, papillary RCC and chromophobe RCC showed 23.96%, 24.75% and 31% of mean Ki-67 expression respectively. Both molecular markers were positively correlated overall.Conclusions: PCNA and Ki-67 expression is increased in RCC when compared with normal tissues and it increases with Stage of RCC. PCNA expression is positively correlated with Ki-67 in different stages and histopathological groups of RCC.

Does statin pre-treatment affect right atrial myocyte apoptosis in coronary artery bypass graft patients? an in-vivo pilot study

Background: This study aims to investigate the possible protective effects of statin pretreatment against right atrial myocyte apoptosis in patients undergoing coronary artery bypass grafting. Methods: Twenty-nine consecutive patients were included in the study. Group 1 patients (n=12; male: 83.3%) were initiated on atorvastatin 40 mg/day on the day of hospital admission and group 2 patients (n=17; male: 82.3%) did not receive statin therapy. Right atrial samples were taken before cardiopulmonary bypass and fixed in 10% neutral formalin. Immunoperoxidase staining and TUNEL method were performed to detect apoptotic cells. The immunostained active caspase-3 and proliferating cell nuclear antigen (PCNA) cells were counted using a light microscope. Results: The mean apoptotic index was significantly lower in endocardial (p=0.04) and epicardial layers (p=0.01) of group 1 patients compared to those of group 2. Myocardial layer values were similar between the groups (p=0.35). The mean PCNA index in any layers was not significantly different between groups. Conclusion: Statin pretreatment before CABG seems to diminish cardiac myocyte loss, providing an explanation for their beneficial effects seen after open heart surgery.

Determination of cell proliferative activity by immnunohistochemical detection of proliferating cell nuclear antigen in N‐methyl nitrosoureainduced rat mammary tumours

Rodent experimental models are considered useful experimental systems to study mammary cancer, which occurs in rodents as a result of hormonal imbalance, much like the breast cancer in women. Rodent cells are easier to transform by chemical carcinogen due to their relatively poorer controls of genetic stability and DNA repair systems. Proliferating cell nuclear antigen (PCNA) is one of the most sensitive biomarkers to measure the cell proliferative activities in the neoplasms, especially when the otherwise undetectable PCNA protein over‐expresses to the immunohistochemically detectable levels. In the present study, mammary tumours were induced in Sprague Dawley rats by intraperitoneal administration of N‐methyl nitrosourea (MNU) chemical carcinogen. Palpable tumours were noticed after 60 days postinjection (dpi) with average latency period of 144 days, and 12 (46.15%) of 26 rats developed mammary tumours. A total of 18 tumours were diagnosed in 12 rats, including 2 cases (10%) of hyperplasia, 1 (5%) benign and 17 malignant tumours (85%). Malignant tumours included in situ ductal papillary carcinoma (11.11%), in situ ductal cribriform carcinoma (38.88%), invasive tubular adenocarcinoma (5.56%), invasive papillary carcinoma (16.67%) and invasive cribriform carcinoma (22.22%) were. PCNA immunohistochemistry revealed moderate to strong nuclear staining in neoplastic cells, with highest mean PCNA index of 55.53±10.13 in invasive cribriform carcinoma. The PCNA indices were significantly different (p<0.01; one way ANOVA) between control mammary gland, hyperplasia, benign and malignant tumours. It was concluded that the measurement of PCNA expressing cells employing immunohistochemistry can help in the determination of the level of malignancy in MNU‐induced rat mammary tumours.

Morphological evaluation of parathyroid adenomas and immunohistochemical analysis of pcna and ki-67 proliferation markers

Parathyroid adenomas are the most common cause of primary hyperparathyroidism. Biological studies have shown that parathyroid adenomas are monoclonal proliferations. Up to date, five cell types have been identified in normal parathyroid tissues; chief cells, vacuolated chief cells, dark chief cells, oxyphil cells and transitional oxyphil cells. Most parathyroid adenomas are predominantly composed of chief cells. In this study, we aimed to indicate the relationship between the predominant cell type in parathyroid adenomas and proliferating cell nuclear antigen, Ki-67 antigen, and serum parathormone levels and the gland weight. 15 cases who had a diagnosis of parathyroid adenomas were included in the study. Histopathologically, the predominant cell type was determined in all the cases. Paraffin blocks were immunohistochemically stained with proliferating cell nuclear antigen and Ki-67. The average parathormone level of the cases was 239.52 ± 36.61 pg/ml before surgery. Mean gland weight was 1.69 ± 0.49 g. Two of the cases showed atypical adenoma characteristics. The predominant cell type was vacuolated chief cell. Immunohistochemical investigation showed that the mean average Ki-67 index value was 4.26 ± 0.86%. The mean proliferating cell nuclear antigen index was 93.20± 45.72/10³. There was a meaningful relationship between gland weights and serum parathormone levels. There was no meaningful relationship between predominant cell types and serum parathormone levels, proliferating cell nuclear antigen index, and Ki-67 index. The chief cell was identified as the predominant cell type. It can be concluded that parathyroid adenomas come into existence as a result of neoplastic proliferation of chief cells, especially vacuolated chief cells.

Prognostic information of gastric carcinoma using Goseki system in relation to nuclear organizer region (AgNOR) and proliferating cell nuclear antigen (PCNA) expression

Objective: The present study was undertaken to find out the relationship of Goseki grading system (I-IV) with existing classification of WHO, Lauren and tumour differentiation of gastric carcinoma and its prognostic information in relation to AgNOR & PCNA expression. Materials and methods: To assess the reproducibility and usefulness of Goseki grading system thirty five gastric carcinoma were selected from January 2007 to July 2009 in the department of Pathology, Burdwan Medical College in West Bengal, India and analyzed in relation to existing grading system by chi-squared testing. Mean AgNOR count & mean PCNA leveling index quantities of different tissue sections were assessed according to different classification system of gastric carcinoma and interobserver variations of all data were evaluated from Spearman Rank-order Correlation Coefficient (rs ). Results: Highly significant predictable correlation of Goseki grading system for existing classification of gastric carcinoma was obtained statistically. Increasing values of mean AgNOR count and PCNA leveling index (2.35% & 15.14%, 2.91% & 21.32%, 3.08 %& 24.76% and 3.2% & 25.12 respectively) were observed from Grade I – IV of Goseki grade. Mucin rich (3.05% & 23.22%) and tubule poor (3.14% & 24.76%) tumours higher values than mucin poor (2.71% & 19.95%) and tubule rich (2.63% & 18.23%) tumors. No significant correlations were observed in other grading system. Conclusion: Following Goseki grading system increasing expression of proliferating marker in mucin rich than mucin poor tumours and tubules poor than tubules rich tumors indicate poor prognosis and tumour behavior. Simple system may help to select patients for adjuvant therapy. Key words: Goseki grade; gastric carcinoma; AgNOR; PCNA. DOI: 10.3329/bjms.v9i2.5655Bangladesh Journal of Medical Science Vol.09 No.2 Apr 2010 pp.76-86

Erbb2 Suppresses DNA Damage-Induced Checkpoint Activation and UV-Induced Mouse Skin Tumorigenesis

The Erbb2 receptor is activated by UV irradiation, the primary cause of non-melanoma skin cancer. We hypothesized that Erbb2 activation contributes to UV-induced skin tumorigenesis by suppressing cell cycle arrest. Consistent with this hypothesis, inhibition of Erbb2 in v-ras(Ha) transgenic mice before UV exposure resulted in both 56% fewer skin tumors and tumors that were 70% smaller. Inhibition of the UV-induced activation of Erbb2 also resulted in milder epidermal hyperplasia, S-phase accumulation, and decreased levels of the cell cycle regulator Cdc25a, suggesting altered cell cycle regulation on inhibition of Erbb2. Further investigation using inhibition or genetic deletion of Erbb2 in vitro revealed reduced Cdc25a levels and increased S-phase arrest in UV-irradiated cells lacking Erbb2 activity. Ectopic expression of Cdc25a prevented UV-induced S-phase arrest in keratinocytes lacking Erbb2 activity, demonstrating that maintenance of Cdc25a by Erbb2 suppresses cell cycle arrest. Examination of checkpoint pathway activation upstream of Cdc25a revealed Erbb2 activation did not alter Ataxia Telangiectasia and Rad3-related/Ataxia Telangiectasia Mutated activity but increased inhibitory phosphorylation of Chk1-Ser(280). Since Akt phosphorylates Chk1-Ser(280), the effect of Erbb2 on phosphatidyl inositol-3-kinase (PI3K)/Akt signaling during UV-induced cell cycle arrest was determined. Erbb2 ablation reduced the UV-induced activation of PI3K while inhibition of PI3K/Akt increased UV-induced S-phase arrest. Thus, UV-induced Erbb2 activation increases skin tumorigenesis through inhibitory phosphorylation of Chk1, Cdc25a maintenance, and suppression of S-phase arrest via a PI3K/Akt-dependent mechanism.

Retrospective – systematic study and quantitative analysis of cellular proliferation and apoptosis in normal, hyperplastic and neoplastic perianal glands in dogs

Neoplasms in the perianal region are frequently diagnosed in dogs. The aetiology is unknown, and most of them are benign. In this study, 240 neoplasms of the perianal glands of dogs were retrieved from the Department of Pathology archives of the Faculty of Veterinary Medicine and Zootechny of University of São Paulo (FMVZ/USP), from 1984 to 2004. All 240 cases were re-examined by two pathologists. Nine cases (4%) were diagnosed as hyperplasia, 49 (20%) as group I adenoma, 81 (34%) were classified as moderately differentiated adenomas of the group II, 46 (19%) were poorly differentiated adenomas of group II, 48 (20%) were carcinoma of the group III according to the classification proposed by Berrocal, and 7 (13%) were other kind of tumours. Males over 8 years of age were predominantly affected. Cell proliferation was quantified by counting proliferating cell nuclear antigen (PCNA) positive nuclei, and apoptosis was quantified by counting fluorescent eosin-stained apoptotic corpuscles (AC) in normal tissue, hyperplasia and in different histologic types of neoplasia of these glands. A parallel pattern of increase in both parameters (cell proliferation and apoptosis) was obtained. The net growth index (NGI), represents how much a cell population is proliferating or dying and was achieved by dividing the mean PCNA count in 1000 cells by the mean AC stain count in 1000 cells. NGI was different between hyperplasia and neoplasia; group I adenomas have a much higher potential of growth, and NGI decreases from benign towards malignant lesions. These results show up the importance of studying cell proliferation and apoptosis to understand the carcinogenesis of dog perianal gland.

Expression of Mina53 and its Significance in Gastric Carcinoma

To study the expression of Mina53 and its relationships with clinicopathological characteristics, antioncogene inactivation and tumor proliferation in human gastric carcinoma, and to explore the role of Mina53 in carcinogenesis and tumor progression. Expression of Mina53 and proliferating cell nuclear antigen (PCNA) was determined in gastric carcinoma (n=79), gastric dysplasia (n=21) and normal gastric tissues (n=20), while p53 was measured in gastric carcinoma tissues by immunohistochemistry. Mina53 was negatively expressed in all normal mucosa tissues. Dysplasia specimens showed weakly positive staining for Mina53 in 3 of 21 cases. Elevated expression of Mina53 was observed in 72 (91.1%) of the gastric carcinomas. No significant associations were found between Mina53 and clinicopathological characteristics such as sex, age, histological differentiation, distant metastasis and lymph node metastasis (p>0.05). There was a significant association with depth of invasion (X2=5.385, p<0.05) and TMN stage (X2=6.255, p<0.05). In gastric carcinoma, positive staining for p53 was detected in 53 of 79 cases (67.1%), showing a significant association with Mina53 (X2=5.161, p<0.05). The mean (+/- SD) PCNA labeling index for gastric carcinoma was 39.47+/-16.92%. Mina53 expression was positively associated with PCNA level (r=0.756, p<0.01). Mina53 was overexpressed in gastric carcinoma and associated with tumor proliferation and antioncogene inactivation. Mina53 could therefore play an important role in the carcinogenesis and progression of gastric carcinoma.

Expression of Mina53 and its significance in gastric carcinoma

To study the expression of Mina53 and its relationships with clinicopathological characteristics, antioncogene inactivation and tumor proliferation in human gastric carcinoma, and to explore the role of Mina53 in carcinogenesis and tumor progression. Expression of Mina53 and proliferating cell nuclear antigen (PCNA) was determined in gastric carcinoma (n=79), gastric dysplasia (n=21) and normal gastric tissues (n=20), while p53 was measured in gastric carcinoma tissues by immunohistochemistry. Mina53 was negatively expressed in all normal mucosa tissues. Dysplasia specimens showed weakly positive staining for Mina53 in 3 of 21 cases. Elevated expression of Mina53 was observed in 72 (91.1%) of the gastric carcinomas. No significant associations were found between Mina53 and clinicopathological characteristics such as sex, age, histological differentiation, distant metastasis and lymph node metastasis (p>0.05). There was a significant association with depth of invasion (X2=5.385, p<0.05) and TMN stage (X2=6.255, p<0.05). In gastric carcinoma, positive staining for p53 was detected in 53 of 79 cases (67.1%), showing a significant association with Mina53 (X2=5.161, p<0.05). The mean (+/- SD) PCNA labeling index for gastric carcinoma was 39.47+/-16.92%. Mina53 expression was positively associated with PCNA level (r=0.756, p<0.01). Mina53 was overexpressed in gastric carcinoma and associated with tumor proliferation and antioncogene inactivation. Mina53 could therefore play an important role in the carcinogenesis and progression of gastric carcinoma.

Role of Heparin on TNF-α and IL-6 Levels in Liver Regeneration after Partial Hepatic Resection

Objectives: The aim of this study was to investigate the effect of heparin on TNF-α and interleukin (IL)-6 levels and the complement system in liver regeneration in a murine model. Materials and Methods: 32 Wistar albino female rats weighing between 180 and 250 g were included in the study. The rats were divided into four groups as follows: group 1, treated with partial (50%) hepatectomy and intravenous heparin 1,000 IU/kg in repeated daily doses; group 2, treated with sham operation and intravenous heparin 1,000 IU/kg in repeated daily doses; group 3, treated with partial (50%) hepatectomy, and group 4 (controls), treated with only sham operation. Before the surgical intervention and after a general anesthetic had been administered to all rats, blood was taken from the left ventricle of each rat, and each sample was assessed to determine total complement hemolytic activity (CH₅₀/ml). On the 5th postoperative day, blood was taken to assess CH₅₀ activity and the levels of TNF-α and IL-6 via ELISA. Each rat was then killed by decapitation after which gravimetric analysis and immunohistochemical staining for proliferating cell nuclear antigen (PCNA) were performed. Results: Serum CH₅₀ activity of group 1 was 4% as compared to 51% in group 3 (p = 0.01). The serum TNF-α level of group 1 was 43 pg/ml as compared to 86 pg/ml in group 3 (p = 0.002). The serum IL-6 level of group 1 was 19 pg/ml as compared to 44 pg/ml in group 3 (p = 0.02). The serum IL-6 level of group 2 was 4 pg/ml as compared to 44 pg/ml in group 3 (p = 0.005). According to the results of gravimetric analysis, the mean regeneration rate of group 1 was 4.4% as compared to 22% of group 3 (p = 0.001). The mean PCNA index values of group 2 was the highest of all groups (p = 0.01). However, the mean PCNA index value of group 1 was the lowest of all groups (p = 0.01). Conclusion: Because of its anti-inflammatory action via the complement system, heparin produced an unfavorable effect on liver regeneration.

CLASSICAL OSTEOBLASTOMA, ATYPICAL OSTEOBLASTOMA, AND OSTEOSARCOMA. A COMPARATIVE STUDY BASED ON CLINICAL, HISTOLOGICAL, AND BIOLOGICAL PARAMETERS

To investigate the biological behavior of classical and atypical osteoblastomas in comparison to osteosarcomas. Based on histological parameters, 30 osteoblastomas were subclassified as classical osteoblastomas (23/30) or atypical osteoblastoma (high cellularity, prominent blue osteoid, and epithelioid osteoblasts--7/30). Comparative immunohistochemical and clinical analysis was performed in 17 cases of patients with high-grade osteosarcoma. Formalin-fixed, paraffin-embedded archival tissue was immunostained for p53 and proliferation cell nuclear antigen. Tumors with positive p53 stain underwent molecular analyses for fragments of exon 10. The mean proliferating cell nuclear antigen indexes for classical osteoblastoma, atypical osteoblastoma, and osteosarcoma were 33%, 61%, and 79%, respectively. The atypical subgroup showed similar results to those of the osteosarcoma group (P < 0.001). p53 protein was detected in 4 (13%) osteoblastomas (3 of these were atypical osteoblastoma), and 4 osteosarcomas (23%) also showed p53 positivity. DNA mutation performed in p53-positive cases was confirmed in exon 10 in 2 atypical osteoblastomas (2/3), 1 classical osteoblastoma (1/1), and 1 osteosarcoma (1/4). Disease recurrence was correlated with p53 expression (P = 0.009), atypical subtype (P = 0.031), spiculated blue bone on histology (P = 0.018), and proliferating-cell nuclear antigen labeling index > or =40 (P = 0.015). These results validate atypical osteoblastoma as an entity, with p53 and proliferation cell nuclear antigen immuno-expression closer to that of osteosarcoma than of classical osteoblastoma. Proliferating cell nuclear antigen labeling index and p53 may be useful predictors of recurrence.

Comparison of Argyrophilic Nucleolar Organiser Regions (AgNORS) with Proliferating Cell Nuclear Antigen (PCNA) in Different Grades of Transitional Cell Carcinoma of Urinary Bladder

Objective : To Compare Argyrophilic Nucleolar Organiser Regions (AgNORs) pattern with Proliferating nuclear antigen (PCNA) in different grades of transitional cell carcinoma. Design : Descriptive and Comparative study. Material and Methods : A total of fifty transurethrally resected bladder tumour samples (TUR BT) were collected from Mayo Hospital, Lahore and Services Hospital, Lahore and processed for H&E, AgNOR stain and PCNA stain. The grading of tumours were made on H&E stain. While AgNOR pattern and PCNA labeling index were recorded for each case. Results : A significant higher proportion of cases (p<0.02) with 3+ AgNOR dispersion were seen in grade III tumours. The AgNOR proliferative index in grade III tumour was significantly higher (p<0.05) as compared with grade II tumours. The cases with AgNOR dispersion of 3+ had significantly higher mean PCNA labeling index (p<0.02) when compared tumours of 2+ AgNOR dispersion. Conclusion : AgNOR and PCNA have significant role in grading of transitional cell carcinoma. The demon-stration of AgNOR dispersion is also a simple and cost effective procedure and could be considered as a substitute for PCNA labeling index. Key words: Nuclear organizer regions, PCNA, Transitional cell carcinoma.

Correlation between proliferating cell nuclear antigen and p53 protein expression and 5-year survival rate in nasopharyngeal carcinoma

Purpose To assess the prognostic significance of p53 protein and proliferating cell nuclear antigen (PCNA) expression in nasopharyngeal carcinoma. Materials and methods This study included 79 patients who had received treatment and regular follow-up for at least 5 years at a single institute. We used immunohistochemistry staining to assess p53 protein expression and PCNA labeling index (LI). Analyses were conducted on the association between each of the 2 biomarkers and pathological subtypes, TNM stage, the presence of locoregional recurrence, and 5-year survival rate. Results p53 Protein nuclear staining was positive in 49 patients (62%). The mean PCNA LI was 55.6%, ranging from 3.35% to 92.9%. High PCNA LI (>55.6%) might contribute to higher 5-year survival rate, but it did not reach statistical significance ( P = .09). Positive p53 protein staining and low PCNA LI were associated with the presence of locoregional recurrence. No statistical significance was found between p53 protein expression and PCNA LI and pathological subtypes and TNM stage. Conclusion p53 Protein and PCNA LI were not an ideal prognostic indicator in predicting 5-year survival rate in nasopharyngeal carcinoma. Future work will direct toward searching for other potential biomarkers with the hope to reinforce prediction of prognosis.

Clinicopathological Profile of Oral Soft Tissue Sarcoma

Objective: To ascertain the clinicopathological profile of oral soft tissue sarcoma.Patients and Methods: Between 1980 and 2000, twelve patients with oral soft tissue sarcoma were evaluated for the expression profile of tumour suppression gene products (p53, pRB, p16) proliferating cell nuclear antigen labelling index; invasive and metastatic potential by matrix metalloproteinase expression; and intratumoural microvessel density.Results: Oral soft tissue sarcomas generally presented as asymptomatic masses. All patients were treated by surgery except for 2 who had distant metastasis at presentation. Local recurrences after surgery were observed in 6 of the 10 operated patients (60.0%), and distant metastasis occurred in 7 of 12 patients (58.3%). Nine patients (75.0%) died despite treatment. In immunohistochemical studies, overexpression of p53 was noted in 6 of the 10 operated patients (60.0%) and loss of p16 expression was noted in 8 patients (80.0%). The mean proliferating cell nuclear antigen labelling index was 31.4%. Matrix metalloproteinase-2 and matrix metalloproteinase-9 expression was observed in all patients and the tumours showed low intratumoural microvessel density (mean, 4.5 per examination area).Conclusion: These observations illustrate the well-recognised high proliferative potential and aggressiveness without angiogenesis of oral soft tissue sarcomas.

Higher expressions of p53 and proliferating cell nuclear antigen (PCNA) in atrophic oral lichen planus and patients with areca quid chewing

The aim of the study was to examine the expressions of p53 and proliferating cell nuclear antigen (PCNA) in oral lichen planus (OLP) in relation to its clinical behavior and the patients' oral habits. Immunohistochemical study was carried out to investigate the expressions of p53 and PCNA in 56 OLP specimens. The results were correlated with the clinical behavior of the disease and the patients' oral habits. The expression rates were further compared with those of normal oral mucosa (NOM), epithelial hyperkeratosis (EH), epithelial dysplasia (ED), and squamous cell carcinoma (SCC). The staining rate of p53 (28.6%) and PCNA labeling index (LI) (27.6 +/- 8.8%) in OLP were similar to those in EH ( P = .868, .074, respectively), but higher than those of NOM and lower than those of ED and SCC (all P < .05). In OLP, no significant correlations were found between p53 or PCNA expression and the patients' age, gender, lesion duration, location, size, number of site, presence of pain, presence of local irritant, and the habits of alcohol drinking and cigarette smoking (all P > .05). In addition, the mean PCNA LI of p53+ cases was close to that of p53- cases (P = .38). However, the staining rate of p53 in OLP was higher in areca quid (AQ) chewers compared to abstainers (P = .001), and the mean PCNA LI in atrophic cases was higher than that in hypertrophic cases (P = .029). Interestingly, the staining rate of p53 and mean PCNA LI were significantly increased in AQ chewers with atrophic OLP (100%, 36.7% +/- 9.0%, respectively), which were similar to those in ED and SCC (all P > .05). Although this study could not confirm the precancerous nature of OLP by the relatively low p53 and PCNA expression, the results do suggest that atrophic form OLP and patients with AQ chewing habit may have a higher disease activity in view of higher expression rates of p53 and PCNA in the lesions.

Effects ofHelicobacter pyloriinfection on gastric epithelial cell kinetics in patients with chronic renal failure

To evaluate the effects of Helicobacter pylori infection on gastric epithelial cell kinetics in patients with chronic renal failure (CRF). Forty-four patients were enrolled in this study and divided into four groups with respect to their Helicobacter pylori (H pylori) and CRF status. Groups were labeled as follows: 1a: normal renal function, H pylori negative (n = 12), 1b: normal renal function, H pylori positive (n = 11), 2a: CRF, H pylori negative (n = 10), 2b: CRF, H pylori positive (n = 11). Upper gastrointestinal endoscopy was done in all the patients involved in the study. During endoscopical investigation, antral biopsy specimens were taken from each patient. In order to evaluate the cell apoptosis and proliferation in gastric epithelial cells, Bax and proliferating cell nuclear antigen (PCNA) labeling indexes (LI) were assessed with immunohistochemical staining method. For groups 1a, 1b, 2a, and 2b, mean Bax LI was identified as 34.4+/-13.7, 44.1+/-16.5, 46.3+/-20.5, 60.7+/-13.8, respectively and mean PCNA LI was identified as 36.2+/-17.2, 53.6+/-25.6, 59.5+/-25.6, 67.2+/-22, respectively. When the one-way ANOVA test was applied, statistically significant differences were detected between the groups for both Bax LI (P = 0.004 <0.01) and PCNA LI (P = 0.009 <0.01). When groups were compared further in terms of Bax LI and PCNA LI with Tukeyos HSD test for multiple pairwise comparisons, statistically significant difference was observed only between groups 1a and 2b (P = 0.006 <0.01). In gastric epithelial cells, expression of both the pre-apoptotic protein Bax and the proliferation marker PCNA increase with H pylori infection. This increase is more evident in patients with uremia. These findings suggest that uremia accelerates apoptosis and proliferation in gastric epithelial cells.

Clinicopathological study of diffuse type brainstem gliomas: analysis of 40 autopsy cases.

Diffuse type brainstem glioma is one of the most malignant types of brain tumors and the prognosis is extremely poor. The proliferative potential of these tumors is presumed to be very high, but there is little information about the cell kinetics of brainstem glioma because surgical resection is rarely performed. The histological grade, tumor spread, growth potential, and prognosis were evaluated in 40 autopsy cases of diffuse type brainstem glioma. To quantify the growth potentials of individual tumors, the proliferating cell indices of Ki-67 (MIB-1) and proliferating cell nuclear antigen (PCNA) monoclonal antibodies were measured. Mean MIB-1 and PCNA proliferating cell indices were 20.4% (24 cases) and 37.0% (28 cases), respectively, in 34 glioblastomas. The median survival time was 40 weeks in 22 treated patients. The mean PCNA proliferating cell index was 10.8% in four of five anaplastic astrocytomas and the median survival time in four treated patients was 91 weeks. The MIB-1 and PCNA proliferating cell indices of one astrocytoma were 2.9% and 20.3%, respectively, and the survival time was 56 weeks. The overall median survival time was 32 weeks. There was a significant difference in PCNA proliferating cell indices between glioblastomas and anaplastic astrocytomas (p < 0.05) and there was a significant difference in survival time between glioblastomas (40 weeks) and anaplastic astrocytomas plus astrocytoma (74 weeks) among the treated patients (p < 0.05). Supratentorial extension was more frequent in glioblastomas than in anaplastic astrocytomas (p < 0.05). Our results suggest that the majority of diffuse type brainstem gliomas are glioblastoma and the proliferative potential is probably as high as that of adult supratentorial glioblastoma. Supratentorial extension and dissemination are relatively frequent in the advanced stage. Anaplastic astrocytoma or astrocytoma is rarer and less infiltrative and proliferative, and carries a slightly better prognosis than glioblastoma.

Proliferating cell nuclear antigen assessed by a computer-assisted image analysis system in patients with chronic viral hepatitis and cirrhosis

Background. Assessment of liver cell proliferation by immunodetection of proliferating cell nuclear antigen may predict regenerative potential and survival of liver and hepatocellular carcinoma risk in patients with chronic viral hepatitis. Aim. To evaluate proliferating cell nuclear antigen status and its clinical significance in a large cohort of patients with chronic viral hepatitis and different degree of liver damage by a computer assisted imaging analysis system. Materials. Liver biopsies from 358 patients with chronic hepatitis (259 males, 49 years, 63% with hepatitis C infection, 27% with hepatitis B virus, 10% with multiple infections) were studied. Methods. Proliferating cell nuclear antigen was localised by immunoperoxidase on microwave oven pre-treated formalin-fixed, paraffin embedded sections using PC10 monoclonal antibody. Proliferating cell nuclear antigen labelling index was calculated by an automated imaging system (Immagini e Computers, Milan, Italy). Results. Mean proliferating cell nuclear antigen labelling index ranged from 0.1% for patients with minimal changes to 3.6% for those with cirrhosis and hepatocellular carcinoma. Overall, proliferating cell nuclear antigen labelling index was higher in males, in older patients, in multiple infections and in hepatitis C virus compared to hepatitis B virus related cases. By linear regression analysis, proliferating cell nuclear antigen labelling index correlated with older age, male gender, higher transaminase levels, hepatitis C virus, higher histological grading and staging: by multivariate analysis male gender, hepatitis C virus, higher grading and staging resulted as independent variables. Both hepatitis C virus or hepatitis B virus cirrhotics had similar liver cell proliferation rate but those with hepatitis B virus had higher prevalence of liver cell dysplasia with respect to those with hepatitis C virus. Conclusions. Proliferating cell nuclear antigen labelling index was a reliable assay for assessing liver cell proliferation rate in patients with chronic viral hepatitis and correlated with liver disease severity.

Immunohistochemical markers for prognosis of cerebral glioblastomas.

Glioblastoma is the commonest neuroectodermal tumor and the most malignant in the range of cerebral astrocytic gliomas. The prognostic utility of various biological markers for glioblastomas has been broadly tested but the results obtained are regarded as controversial. In the present study, 302 glioblastoma specimens were studied to evaluate a possible association between clinical outcome and expression of some immunohistochemical variables. Furthermore, tumors examined were subdivided on the three cytological subsets--small-cell (SGB), pleomorphic-cell (PGB) and gemistocytic (GGB). Immunohistochemical variables differed between various subsets: the number of p53-positive tumors was found to be prevailed among the PGB, whereas the number of tumors with EGFR and mdm2 positivity was significantly greater in SGB. GGB contained significantly lowest mean proliferating cell nuclear antigen (PCNA) labeling index (LI), greater number of p21ras positive cases, and higher mean apoptotic index (AI). Survival time in patients with SGB, EGFR and mdm2-positivity and PCNA LI >40% was found to be significantly shorter, whereas presence of p21ras and AI >0.5% were associated with prolonged survival. Multivariate analysis revealed that survival time is associated with SGB, EGFR-positivity, and AI (p = 0.0023, p = 0.0035 and p = 0.0029 respectively). We conclude that although some immunohistochemical variables were found to be significant for glioblastoma outcome, they appear to be closely related to biology of single cytological subsets. Furthermore, these variables exhibited no prognostic value when they were analyzed within each cytological subset separately. Therefore, the glioblastoma subdivision on three cytological subsets proposed by us is carrying some element of rationality but, undoubtedly, requires further prospective studies.

Characterization of myocardial hypertrophy by DNA content, PCNA expression and apoptotic index

Background: At present little is known about the biological basis of cellular alterations in myocardial hypertrophy. The present study aims to analyze proliferating cell nuclear antigen (PCNA) expression, DNA content and apoptosis, in several types of myocardial hypertrophy in order to define the biological characteristics of this process. Methods: The biological parameters were investigated in normal hearts ( n=4) and in 21 cases of left ventricular myocardial hypertrophy related to pressure overload ( n=7), post-infarction remodeling ( n=8) and hypertrophic cardiomyopathy (HCM) ( n=8). Results: The analyzed biomarkers were similar in hypertension and in remodeling, with a very high apoptotic index (mean values: 8.1 and 8.5%, respectively), a low PCNA positivity (mean values: 1.8 and 1.6%) and a prevalent diploid DNA content (DNA index: 1.2). Conversely, HCM showed a high mean PCNA index (21.2%) associated with a prevalence of hyperdiploid myocytes (DNA index: 1.8) and a low number of apoptotic cells (mean value: 1.7%). Conclusions: There are significant biological differences between hypertrophy in HCM and that related to arterial hypertension and post-infarction remodeling. Therefore, the combined evaluation of DNA content, PCNA and apoptotic indices could provide a powerful diagnostic tool in doubtful cases of myocardial primary or secondary hypertrophy and open new avenues in the clinical treatment of these entities.