Expression of proliferating cell nuclear antigen (PCNA) in gastric carcinoma: no evidence for prognostic value

It has been proposed that immunostaining with PC10, a monoclonal antibody against proliferating cell nuclear antigen (PCNA), is of prognostic value in gastric carcinoma. Gastric carcinomas from a series of 90 patients in whom survival data were known have been studied. There was no relation between the degree of PC10 immunostaining assessed semiquantitatively and survival.     

Expression of proliferating cell nuclear antigen (PCNA) in premalignant lesions of laryngeal epithelium

It is important to study the proliferative activity of cells in the premalignant lesions of laryngeal epithelium. Using PC-10, an antibody to PCNA and a standard immunohistochemical staining, we examined 11 cases of simple hyperplasia of epithelium (SHE), 32 cases of atypical hyperplasia of epithelium (AHE) and 42 cases of laryngeal squamous cell carcinoma (LSCC) for expression of PCNA, a protein associated with DNA polymerase delta and DNA replication. The results revealed that the PCNA indices in SHE, AHE and LSCC were 9.57%, 27.33% and 68.05%, respectively. The PCNA indices were 13.79%, 30.84% and 39.94%, in the mild, moderate and severe AHE, respectively. There were significant differences among the SHE, AHE and LSCC. A good correlation was found among different degrees of AHE. The pattern and location of PCNA positive cells in the intraepithelium had diagnostic importance. PCNA might provide a useful tool for studying cell proliferation in situ under normal and pathological conditions.     

Recurrence of meningiomas versus proliferating cell nuclear antigen (PCNA) positivity and AgNOR counting

Meningiomas have a wide range of biological potential and clinical behaviour. Histological findings are helpful in recognizing the malignant potential but often fail to correlate with clinical behaviour. This study attempts to correlate the silver nucleolar organizer regions (AgNORs) and proliferating cell nuclear antigen (PCNA) with clinicopathological features of biological activity. Thirty-four completely resected meningiomas were classified as benign [19], atypical [6] and malignant [9]. Forty-eight initial and recurrent tumour materials were investigated for staining of AgNORs and immunohistochemistry using monoclonal antibodies against PCNA (clone 19A2 and PC10). There were no difference between the recurrent and non-recurrent cases with regards to AgNOR, PC10 and 19A2 values. Also, no significant difference was found between the primary and recurrent tumours. Both PC10 and 19A2 labelling indices (LI) showed a significant difference between benign and malignant meningiomas. The 19A2 LI was 0.56 +/- 0.21 in benign and 2.45 +/- 16 in atypical meningiomas. The 19 A2 counts showed significant difference between benign and atypical tumours but PC10 values failed to show such a correlation AgNOR and PCNA indices were not found to be useful in predicting recurrences compared to the surgical procedure and histopathological criteria.     

Expression of the proliferating cell nuclear antigen (PCNA) in the rat thyroid gland after exposure to bromide

Support groups for individuals who stutter provide an opportunity for consumers to incorporate emerging or newly learned fluency skills in speaking situations outside of the speech-language clinic. One major theme of this article is to promote the idea that support groups can be utilized by clinicians and consumers as an important adjunct to fluency therapy. In addition to addressing feelings and attitudes associated with stuttering, the supportive environment of such groups serves to provide individuals who stutter with opportunities to work on improved communication skills with several different communication partners. For many, this is an important step in the successful transfer of fluency skills from the clinic to the "real world."     

p53 and c-jun expression in urinary bladder transitional cell carcinoma: correlation with proliferating cell nuclear antigen (PCNA) histological grade and clinical stage

OBJECTIVE: To investigate p53 and c-jun oncoproteins and proliferating cell nuclear antigen (PCNA) in transitional cell urinary bladder carcinomas (TCCs) and to determine their relationships to tumour grade, stage and survival. MATERIALS AND METHODS: The expression of p53, c-jun and PCNA was studied using immunohistochemistry in formalin-fixed, paraffin-embedded tissues in a series of 110 TCCs. RESULTS: 58% of our cases were positive for p53 and 88% for c-jun. A statistically very significant correlation (p < 0.0001) was observed between p53 and c-jun (r = 0.781), p53 and PCNA (r = 0.772), c-jun and PCNA (r = 0.831) as well as between each of the two oncoproteins and the histological grade and clinical stage (p < 0.001). There was no correlation of either p53, PCNA or c-jun with clinical outcome in terms of patients survival. CONCLUSION: p53 and c-jun proteins' overexpression are strongly related to rapid tumour cell proliferation and hence with aggressive growth in urinary bladder TCC. PCNA score remains an important prognostic index in transitional cell carcinoma of the bladder.     

Prognostic implications of proliferating cell nuclear antigen (PCNA), AgNORs and P53 in non-Hodgkin's lymphomas

We investigated the prognostic value of proliferating cell nuclear antigen (PCNA) and p53 oncoprotein expression and of nucleolar organiser region (NOR) scoring, in relation to classic clinicopathological parameters, in a series of non-Hodgkin's lymphomas (NHL). Paraffin embedded tissue from 91 patients with NHL was stained immunohistochemically with the monoclonal antibodies PC-10 (PCNA) and DO-1 (p53) and histochemically with the AgNOR technique. The median follow-up was 48 (4 to 193) months. The impact of PCNA and p53 expression and of AgNOR number on survival was tested using univariate as well as multivariate analysis, in order to circumvent the heterogeneity in histologic grade, type and therapy. Univariate analysis identified seven variables related to overall survival: histologic type and grade, clinical stage, chemotherapy, p53 labelling index (LI), PCNA LI and AgNOR score, whereas only one parameter i.e. histologic grade influenced disease-free survival. In multivariate analysis stage, PCNA LI and AgNOR score predicted independently overall survival. PCNA was also the only independent predictor of post-relapse survival and histologic grade the most important indicator of disease-free survival. In conclusion, PCNA expression and AgNOR number may be better predictors of overall and post-relapse survival than histologic grade. The latter remains the most valuable prognostic indicator of disease-free survival.     

Methodological aspects of the immunostaining of proliferating cell nuclear antigen (PCNA) in cytospin preparations of MCF-7 cell line

For the purpose of analysing the association between selected current socio-demographic characteristics and the history of induced abortion, 138 students of a Brazilian university, who had been pregnant at least once, were studied. These students were identified from among the 937 who returned, by mail, a self-administered, anonymous questionnaire distributed to all the female undergraduates. The subjects were divided into two groups, those who had and those who did not have a history of induced abortion. It was found that the largest percentage of women who had already had an induced abortion were of less than 24 years of age, were not living in marital union, had no religious affiliation and no living children at the time of the study. Analysis by logistic regression showed that having no living children was the only current characteristic associated with having had an induced abortion.     

Proliferating cell nuclear antigen (PCNA) expressed in human leptomeninges

Here we report on the presence of proliferating cell nuclear antigen (PCNA) in human leptomeninges from 35 normal subjects with ages ranging from 57 to 94 years. Strong immunoreactivity with PC10 (a monoclonal antibody to PCNA) was detected in the nuclei of meningothelial cells, smooth muscle cells of leptomeningeal vessels, and ependymal cells. An immunoblot of leptomeningeal homogenate with PC10 showed the presence of a single band at 35 KD, the expected molecular mass of PCNA. Ki-67, another marker for cell proliferation, was undetectable in human leptomeninges. These observations point to isolated PCNA expression in tissue in which cells are not actively proliferating.     

Detection of proliferating cell nuclear antigen (PCNA) in peripheral blood mononuclear cells and sera of patients with malignant lymphoma

The proximity of farms to badger setts was compared between farms that had experienced a tuberculosis breakdown and those that had not, over the 6 year period from 1988 to 1993. The data were derived from a badger removal study conducted in East Offaly County in the Republic of Ireland. Badger removal began in 1989 and continued through 1993; by the end of 1990, approximately 80% of all badgers caught in the 6 year period had been removed. All badgers were examined, grossly, for evidence of tuberculosis. Tuberculosis status of the approximately 900 study herds was based on the results of the single intradermal comparative skin test and/or lesions of bovine tuberculosis. All herds were tested at least once annually. The number of herds experiencing bovine tuberculosis declined over the period, particularly in the years 1992 and 1993. The data on farm and badger sett location were stored and analysed, initially, in a geographical information system. Owing to the badger removal programme, the distance between the barn yard of a typical farm and the nearest occupied badger sett increased, by about 300 m year-1, and by about 600 m year-1 to the closest infected sett. In bivariate analyses, in the years 1988 and 1989, the risk of tuberculosis declined with increasing distance to a badger sett containing one or more tuberculous badgers. In multivariable logistic regression analyses, year and the average number of cattle tested per farm per year were controlled. A second identical analysis was conducted to control for the repeated observations on the same herds using generalised estimating equations. In both analyses, the risk of a multiple reactor tuberculosis breakdown decreased for herds at least 1000 m away from an infected badger sett, and increased as the number of infected badgers per infected sett increased. Despite the significantly reduced risk of a breakdown with increasing distance to infected badger setts, the relationship was not strong (sensitivity and specificity of the model in the low 70% range) and explained only 9-19% of tuberculosis breakdowns.     

The dual function of the proliferating cell nuclear antigen (PCNA) in the response of human cells to UV damages

An auxiliary protein of DNA polymerases delta and epsilon, the proliferating cell nuclear antigen (PCNA), is necessary for efficient DNA replication in vivo and in vitro, and also for the repair synthesis in vitro, but its role in the excision repair of genome in vivo is not exactly established. In S-phase of unirradiated cells, PCNA is tightly bound to focal centers of DNA replication and is not removed by treatment with detergent Triton X-100, but is completely extracted from non-S-phase cells by the indicated detergent. It was shown earlier that after UV-irradiation PCNA could not be removed by the detergent even from non-S-phase cells. It was interpreted as the evidence of PCNA integration into the repair complex and of the participation of this protein in repair synthesis in vivo. In the present work the data were obtained indicating that the role of PCNA in cell response to UV-damage was not confined only to its possible involvement in repair synthesis. With the help of confocal microscopy it was established that in Triton X-100-extracted normal cells PCNA did not colocalize with the well known excision repair protein XPB/ERCC3, defective in cells from Xeroderma pigmentosum (complementation group B) patients. XPB-protein is induced by UV-irradiation in normal cells, and this induction is not observed in repair deficient cells. However, in such cells UV-light induces a detergent-resistant form of PCNA, and this form is obviously not connected with repair. It cannot be excluded that a rapid PCNA immobilization immediately after UV-irradiation of cells is needed for the facilitation of photochemical damage bypass during the subsequent replication of genome.     

Identification of S-phase cells with PC10 antibody to proliferating cell nuclear antigen (PCNA) by flow cytometric analysis

We estimated the expression of proliferating cell nuclear antigen (PCNA) in HeLa S3 cells by flow cytometry with monoclonal antibody (MAb) PC10. HeLa cells were fixed with six different fixation procedures: 15-min and 30-min acetone, 15-min acetone followed by 15-min methanol (acetone/methanol), 30-min methanol, 15-min methanol followed by 15-min acetone (methanol/acetone), and a mixture of acetone and methanol. The fixed cells were applied to MAb PC10 against PCNA and then treated with FITC. With five fixation procedures except for acetone/methanol, PCNA was expressed in almost all cells with similar shapes and different FITC intensity levels on PCNA/DNA bivariate cytograms, whereas acetone/methanol fixation allowed PCNA detection in S-phase cells with a cytogram that showed a horseshoe-like pattern with a peak level at mid-S-phase. Flow cytometric dual parameter analysis of PCNA/BrdU was carried out in HeLa cells to confirm detection of PCNA in S-phase cells with acetone/methanol fixation. The population of cells stained for both parameters, i.e., S-phase cells, was obviously discriminated from that of the non-S-phase cell in PCNA/BrdU bivariate cytograms. These results strongly suggest that PCNA used with acetone/methanol fixation would be equal to BrdU as an S-phase marker.     

Analysis of proliferative activity using anti-proliferating cell nuclear antigen antibody in gastric cancer tissue specimens obtained by endoscopic biopsy

BACKGROUND: Proliferative activities of tumors are thought to be prognostic features of malignant tumors, but their value as measured by proliferating cell nuclear antigen (PCNA) labeling remains unclear in gastric cancer. METHODS: PCNA labeling rates (LR) were quantified in 121 paraffin-embedded biopsy specimens from primary tumors by immunocytochemistry. RESULTS: Immunohistochemical analyses have demonstrated that PCNA presents an intense staining in the nuclei of tumor cells and mucous neck cells of gastric glands. The PCNA LR ranged from 12% to 79% (mean +/- standard deviation), and a significant correlation was found between bromodeoxyuridine labeling indices and PCNA LR: PCNA LR were closely associated with tumor size, serosal invasion, and nodal involvement. The patients with tumors with high PCNA LR (greater than 40%) were dead significantly earlier than were those with tumors with low PCNA LR: When the PCNA LR and all the clinicopathologic parameters were entered into a Cox regression model, PCNA LR emerged as an independent prognostic factor. CONCLUSION: These results indicate that PCNA LR may be a potentially useful prognostic factor for gastric cancer.     

Expression of proliferating cell nuclear antigen in corneas kept in long term culture

PURPOSE: To investigate the proliferative activity of the donor corneal cells and to examine how this property changed during long term culture. METHOD: Fourteen human corneas from donors (ages from 50-91) were cultured in the medium (MEM+8% FBS with or without dextran). The proliferating status of corneal cells was evaluated by immunohistochemical staining of proliferating cell nuclear antigen (PCNA) in the cells. Three corneas at each time point were fixed in paraformalin at day 0, day 3 and after 3 weeks cultured in medium as well as 3 weeks plus 2 or 5 days in fresh medium with 8% dextran. Paraffin-embedded corneas were sectioned to 4 microm and stained with antibody PC 10 against PCNA. The number of PCNA positive cells was identified under light microscope. RESULT: Prior to organ culture only basal limbal epithelial cells stained positive for PCNA. After 3 days in culture 50 percent of the epithelial cells were positive as were several keratocytes and some endothelial cells in the peripheral corneas. After 21 days no cells showed proliferative activity. After 21 days in culture and 5 days in fresh deswelling medium the essentially monolayered epithelium stained positively in the limbal area. The proliferative activity of the keratocytes in the anterior stroma was extensive. Endothelial cells stained positive in the peripheral cornea. CONCLUSION: Limbal epithelial cells appear to survive in the organ culture. The corneas may be worth evaluating as sources of stem cells for grafting. Likewise, the keratocytes survive organ culture and can be induced to proliferate after a change to fresh medium. The endothelium is stimulated to proliferate in organ culture and in fresh medium after long term storage.     

Proliferative activity of gastric cancer assessed by immunostaining for proliferating cell nuclear antigen

The growth activity of 107 gastric carcinomas was assessed by immunohistochemical staining for formalin-fixed, paraffin-embedded tissue with a monoclonal antibody against proliferating cell nuclear antigen (PCNA). When the tumor doubling times (Tds) of 10 patients were estimated from the serum levels of carcinoembryonic antigen and carbohydrate antigen 19-9, there was an inverse correlation between the Tds and PCNA labeling index (LI) at P = 0.055. Flow-cytometric analysis was carried out by double staining for PCNA and DNA using fresh materials from 14 patients. The PCNA-positive cell fraction revealed by flow cytometry showed a good linear correlation with PCNA LI in routinely stained tissue. The LI of well-differentiated adenocarcinoma was significantly higher than that of the poorly differentiated type. When the LI was analyzed in well- or poorly differentiated adenocarcinoma, the value was significantly higher in the well-differentiated type with hepatic metastasis and in the poorly differentiated type with lymph node metastasis.     

Proliferating cell nuclear antigen (PCNA) immunostaining--a prognostic factor in ovarian cancer?

The measurement of tumour cell proliferation is becoming increasingly recognised in defining prognostic groups. Proliferating cell nuclear antigen (PCNA) immunolocalisation can be used as an index of cell proliferation and may define the extent of departure from normal growth control. The monoclonal antibody PC10 stains PCNA in archival paraffin-embedded tissue. This study investigates its potential as a prognostic marker in early and advanced ovarian cancer. A three-stage immunoperoxidase technique was developed to detect the monoclonal antibody PC10. Archival paraffin-embedded tissue from 19 stage I ovarian tumours (13 malignant and six borderline) and 79 advanced (stage IIb-IV) ovarian tumours (patients entered into the Third North-West Thames Ovarian Cancer Trial) was immunostained with PC10. PC10 immunostaining was performed successfully in 91.8% of cases. The PC10 labelling index (PC10 LI) ranged from 1.5% to 88% with a mean value of 47.4%. Stage I borderline tumours had significantly lower PCNA labelling indexes than stage I malignant tumours (P < 0.048). In advanced disease there was an inverse correlation between PC10 and overall survival, and in those patients who underwent good debulking surgery (37 patients with disease < 2 cm diameter) a low PC10 value (< 36.5%) correlated with improved survival (log-rank trend test for survival, chi 2 = 5.75, P = 0.017). PCNA immunostaining defines a good prognostic subgroup in adequately debulked patients with ovarian cancer.     

Proliferating cell nuclear antigen (PCNA) expression in oral squamous cell carcinoma - an aid to conventional histological grading?

Decreased oxygen delivery and cellular hypoxia are major factors in the pathophysiology of shock. We studied the effects of 100% O2 at 0.1 and 0.3 MPa (1 and 3 atm abs) in severe hemorrhagic shock in awake, unrestrained rats. Shock was induced by withdrawing 50% of the total blood volume within 120 min. Blood pressure, heart rate, and the electroencephalogram (EEG) were recorded during the first 6 h of the protocol. The animals were observed for 7 days. The shock protocol resulted in 60 and 90% mortality after 1 day and at the end of 7 days, respectively. A single 90-min exposure to O2 at 0.1 and 0.3 MPa, which was started 30 min after bleeding, maintained mean arterial blood pressure at significantly higher values compared to untreated controls throughout the exposure period (P < 0.05). Oxygen therapy at both doses also improved the long-term survival rate and survival time significantly (P < 0.01). No clinical or EEG sign of CNS O2 toxicity was detected in O2-treated animals. Our results indicate that O2 given alone after severe bleeding exerts a beneficial effect on the long-term outcome of hemorrhagic shock in awake, unrestrained rats.     

Immunohistochemical studies of proliferating cell nuclear antigen and cathepsin D in transitional cell carcinoma of the urinary bladder

Immunohistochemical staining for proliferating cell nuclear antigen (PCNA) and cathepsin D was performed on 60 transitional cell carcinoma (TCC) specimens from 60 patients with bladder cancer. The percentage of PCNA-positive cells (PCNA-labelling index) was determined by counting 500 or 1,000 cells, and cathepsin D expression was graded according to the extent of immunoreactivity to anti-cathepsin D antibody. The PCNA-labelling index was significantly higher in high-grade and high-stage tumors compared to that in low-grade and low-stage tumors. Cathepsin D was highly positive in grade-1 tumors. In contrast, 82% of grade-3 tumors and 76% of advanced tumors showed negative or low reactivity to anti-cathepsin D. Groups of high PCNA-labelling index and negative cathepsin D had significantly poorer prognoses compared to those of the low PCNA group and cathepsin D highly positive group, respectively, in univariate analyses. However, neither of these two factors were independent prognostic factors in multivariate analyses. These results suggest that the PCNA-labelling index and cathepsin D expression may indicate the malignant potential of TCC and may be able to provide additional information for predicting survival when stratifying for grade of bladder cancer.     

Clinical relevance of p53 index and expression of proliferating cell nuclear antigen and Ki-67 in gastric cancer

To improve the therapeutic outcome for inoperable non-small-cell lung cancer, we applied definitive thoracic radiotherapy combined with concurrent administration of carboplatin and etoposide. We retrospectively analyzed 55 eligible patients with Stage III disease. The one-year rate of overall survival (OAS) and distant metastasis-free survival (DMFS) of the total group were 46.1% and 36.1%, respectively. Twenty-nine patients developed thoracic failures (52.7%) and 23 (41.8%) distant failures. Using univariate and multivariate analyses, radiation dose, performance status and LDH were revealed as significant prognostic factors of OAS, and LDH had a strong adverse effect on DMFS. Leucopenia of Grade 3 or higher was noted in 75.9%, anemia in 55.6%, thrombocytopenia in 59.3%, esophagitis in 20.4%, and lung injury in 10.9%. Sufficient gain was not obtained by our strategy, and higher morbidity, especially of lung, was noted than was expected. It was suspected that simultaneous use of oral etoposide might increase radiation pneumonitis, so one should take special care of unexpected toxicity in concurrent chemoradiotherapy. Both the hyperfractionated technique of radiotherapy and the time-dose modification of anti-tumor drugs should be considered in further steps.     

Proliferative potential of meningiomas evaluated by proliferating cell nuclear antigen expression

Meningiomas are principally benign in nature. Some meningiomas, however, grow fast or recur even after total removal. The biological behavior of meningiomas often can not be predicted from conventional histopathological studies. A monoclonal antibody against proliferating cell nuclear antigen (PCNA) was used to investigate the usefulness of the PCNA index as a parameter to estimate the proliferative activity of meningiomas. Fifty-two meningiomas were examined. The mean PCNA index of recurrent meningiomas (3.37 +/- 0.92%) was significantly higher than that of non-recurrent meningiomas (1.12 +/- 0.51%) (p < 0.005). The PCNA indices of recurrent cases were all higher than 2.0%. A semilog linear regression analysis between tumor doubling time and PCNA index showed a significant correlation (r = 0.90, p < 0.05). An inverse linear correlation between PCNA index and interval to recurrence was observed (r = 0.62, p < 0.05). A good linear correlation was also shown between PCNA index and BUdR labeling index (r = 0.88, p < 0.01). The results of this study suggest that, providing the methods of tissue processing, immunostaining and counting of positive nuclei are unified, the PCNA index is a useful parameter for estimating the biological behavior of meningiomas.