Prognostic significance of proliferating cell nuclear antigen (PCNA) expression in gliomas

The relationship between proliferating cell nuclear antigen (PCNA) expression and various clinicopathological indices (age, sex, tumour location, histological type and grade and treatment) and post-operative survival were studied in patients with central nervous system gliomas using univariate and multivariate analysis. The expression of PCNA (PC10 score) was examined immunohistochemically using the monoclonal antibody PC10 on paraffin sections from 45 cases. Univariate analysis showed that a high PC10 score as well as older age, high histological grade and the histological type (astrocytoma) were associated with reduced survival. However, multivariate analysis revealed that only PC10 score and histological type had independent prognostic significance. The most important feature influencing PC10 score was the tumour grade. Regarding the patients who relapsed, the survival from the time of original diagnosis was related to the relapse-free period, while the PC10 score of the primary tumour emerged as the only independent predictor of survival following the first recurrence. These results indicate that PCNA expression is an independent prognostic indicator in CNS gliomas.     

Proliferation in malignant mesothelioma as determined by mitosis counts and immunoreactivity for proliferating cell nuclear antigen (PCNA)

In order to assess its discriminating and prognostic value, we studied immunoreactivity for proliferating nuclear cell antigen (PCNA) in human malignant mesothelioma (31 cases) and in human non-neoplastic mesothelium (33 cases with reactive mesothelium and 20 cases of normal mesothellum) using the murine monoclonal antibody PC 10. We also compared it with mitosis counts expressed as the mitotic volume index (MV index). There were differences between malignant mesothelioma, reactive mesothelium, and normal mesothelium for percentage of PCNA immunoreactive cells (mean ± SD; 27 ± 9, 9·5 ± 5·1, and 3·6 ± 1·6, respectively) and for their MV index (20·3 ± 4·5, 9·4 ± 2·1, and 3·6 ± 0·6, respectively). The median actuarial survival was 10·1 months for patients with less than 25 per cent PCNA immunoreactive cells, 9·4 months for patients with less than 20 mitoses per mm² of tumoural tissue, 5·9 months for patients with more than 25 per cent PCNA immunoreactive cells, and 5·3 months for patients with more than 20 mitoses per mm² of tumoural tissue. Our results suggest that PCNA immunoreactivity is useful in discriminating between neoplastic and non-neoplastic mesothelium and that it may have prognostic value in malignant mesothelioma.     

The clinical significance of autoantibodies to the proliferating cell nuclear antigen (PCNA)

Autoantibodies targeting the proliferating cell nuclear antigen (PCNA) were first described over 30 years ago and are historically most commonly associated with systemic lupus erythematosus (SLE). The primary antigenic target is a 34 kDa protein that is part of the DNA polymerase delta multi-protein complex. A number of diagnostic platforms have incorporated PCNA into their diagnostic assays and algorithms. However, little is known about the clinical utility of autoantibodies to PCNA, especially with novel detection systems. This review will focus on the history of the discovery of the PCNA autoantigen and the current status of the diagnostic significance of anti-PCNA and suggest future studies that are required to strengthen our understanding of their clinical utility.     

Expression of proliferating cell nuclear antigen (PCNA) in dysplasia of the bronchial epithelium

Proliferating cell nuclear antigen (PCNA) is expressed in cells in the cell cycle and has been studied as a marker of proliferation in lung and other tumours. We have noted immunocytochemical differences in PCNA expression between normal and neoplastic bronchial cells. As bronchial dysplasia is considered preneoplastic, we have examined PCNA expression in this condition. PCNA staining in 47 cases of bronchial dysplasia and 32 samples of normal bronchial epithelium was compared. Of the dysplasias, three were mild, 11 moderate, and 33 severe. A significant increase in PCNA counts over normal epithelium was seen only in moderate and severe dysplasias. In dysplasia, mitotic indices showed a significant positive correlation with the percentage of PCNA-positive cells. We conclude that in moderate and severe dysplasias there is an increase in the number of cells expressing PCNA and undergoing division, indicating abnormal growth control.     

增殖细胞核抗原阳性细胞在幼年大鼠前脑的分布

目的　探讨幼年大鼠前脑内是否存在增殖细胞。方法　用增殖细胞核抗原 (PCNA)单克隆抗体PC10免疫组化研究。结果　PCNA阳性反应部位分两类 :一类为圆形或卵圆形深染颗粒 ,具有核的形态和大小 ,主要分布于吻侧迁移流、室管膜下带和部分血管壁 ;散在分布于尾壳核、运动皮质、隔区和斜角带 ;有时见“镜影核” ,主要存在于尾壳核 ;另一类为整胞体染色 ,见于室管膜、室管膜下带和吻侧迁移流。结论　幼年大鼠前脑内存在增殖细胞     

Immunohistochemistry of proliferating cell nuclear antigen (PCNA), laminin, and electron microscopy by tannic acid fixation in surface epithelial-stromal ovarian tumors

The distribution of proliferating cell nuclear antigen (PCNA), laminin, and basement membrane in surface epithelial-stromal ovarian tumors was studied using immunohistochemical and cytochemical techniques. PCNA is a useful means of differentiating between borderline and malignant tumors. The distribution of laminin-positive materials in malignant tumors showed that laminin synthesis in these tumors is quite different from that which occurs in benign or borderline tumors. This corresponded with electron microscopic findings by tannic acid fixation showing pleomorphism of cell organelles and discontinuity of the basement membrane in malignant tumors.     

Haemangiopericytomas: the prognostic value of immunohistochemical staining with a monoclonal antibody to proliferating cell nuclear antigen (PCNA)

Forty-two cases of haemangiopericytoma were studied retrospectively using immunohistochemical staining with PC10, a monoclonal antibody to PCNA. The percentage of tumour cells with positive staining for PCNA was found to correlate well with histological grading. Clinical follow-up data were available in 25 adults and showed no known deaths in 11 cases with a low proportion (less than 14%) of positive cells. Out of 14 cases with a high number (greater than or equal to 14%) of positive cells, seven patients are known to have died, two had metastases, and in a further two there have been multiple recurrences of tumour. DNA flow cytometry was performed on 26 cases but this showed no correlation with PC10 staining or clinical outcome. Staining with PC10 may be of particular value in the identification of patients at greatest risk of rapid tumour metastasis and early death.     

A study of cell proliferation in formalin-fixed, wax-embedded bone marrow trephine biopsies using the monoclonal antibody PC10, reactive with proliferating cell nuclear antigen (PCNA).

We have investigated proliferation in bone marrow trephine biopsies from 32 patients with normal or abnormal haemopoiesis, using the monoclonal antibody PC10, which detects proliferating cell nuclear antigen (PCNA), together with immunohistochemical markers of haemopoietic cell lineage. PCNA immunostaining revealed the pattern of proliferation within individual haemopoietic lineages in normal marrow. Two unexpected observations were made: of erythroid cells, only pro-erythroblasts and occasional early normoblasts reacted, and positivity of megakaryocytes was unrelated to nuclear lobulation or CD61 expression. The pathological cases represented conditions in which haemopoiesis is increased (reactive hyperplasia, chronic granulocytic leukaemia, myeloproliferative and myelodysplastic syndromes, megaloblastic anaemia). Increases in the number, and disturbances of the spatial organization, of PCNA-expressing cells were present to a variable extent in all cases. Sheets of PCNA-positive megaloblastoid erythrocytes were frequently found in myelodysplastic and myeloproliferative tissue, associated with marked disturbances in the spatial organization of all haemopoietic lineages. Cases of megaloblastic anaemia due to vitamin B12/folate deficiency also demonstrated greatly increased erythroid PCNA expression, with positivity in some giant metamyelocytes. In addition to reflecting increased proliferation, elevated PCNA expression in some bone marrow pathologies may be due to altered kinetics of the protein induced by disturbances in growth factor production.     

Proliferating cell nuclear antigen (PCNA) expression in Hodgkin's disease.

Previous studies of the proliferating cell fraction in Hodgkin's disease (HD) have been directed towards the classical Hodgkin and Reed-Sternberg cells (HRS) to the exclusion of the background population and have not included cases of nodular lymphocyte predominant Hodgkin's disease (NLPHD). Using an antibody to proliferating cell nuclear antigen (PCNA), we have determined the growth fraction of HRS cells and L&H cells in paraffin sections of 15 cases of classical HD [12 nodular sclerosis (NS), 3 mixed cellularity (MC)] and eight cases of NLPHD. By double staining with anti-PCNA and antibodies to B cells (CD20) and T cells (CD45RO), we also determined the growth fraction and immunophenotype of the background population in each case. In classical HD, 50.4 per cent of HRS cells were PCNA-positive and judged to be proliferating, which is comparable to previous studies, while in NLPHD 76.9 per cent of L&H cells were PCNA-positive. In both classical HD and NLPHD, the majority of PCNA-positive cells in the background were T cells, which showed a growth fraction of 57.8 and 68.5 per cent, respectively; in comparison, only 4 per cent of B cells were PCNA-positive in each type of HD. L&H cells are widely accepted to be B cells and there is growing evidence that HRS cells are also B cell-derived. Our results underline a relationship between classical HD and NLPHD and suggest that the characteristic histological features of both diseases may be caused by the production and release of cytokines from altered B cells.     

Assessment of rejection in orthotopic human heart transplantation using proliferating cell nuclear antigen (PCNA) as an index of cell proliferation.

Myocardial biopsies taken during the management of cardiac transplantation were stained for proliferating cell nuclear antigen (PCNA). Counts of PCNA-positive interstitial cells were compared, in retrospect, with the reported histological grade of rejection. Biopsies without rejection had negligible numbers of PCNA-positive cells. Ascending grades of rejection were paralleled by an increase in the number of PCNA-positive cells [grade 1, 13 +/- 35 (mean +/- SD); grade 2a, 38 +/- 40; grade 2b, 91 +/- 75; grade 3, 170 +/- 78]. While highly significant, in statistical terms, the overlap in the counts between different grades means that prediction of rejection from the PCNA count alone is not feasible. Biopsies graded as 0 or 1 and which immediately preceded more severe rejection episodes showed no increase in PCNA-positive cells. The majority of PCNA-positive cells are fibroblasts, although in grade 2b and 3 rejection a small population of PCNA-positive T lymphocytes occurs. PCNA staining is also seen in cardiac myocytes immediately after transplantation, during rejection episodes, and late after transplantation in the absence of rejection. The positive PCNA staining of cardiac myocytes probably reflects DNA synthesis that occurs with the shift toward polyploidy in hypertrophy.     

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

Cytospins of a human breast cancer cell line (MCF-7) were studied for the expression of PCNA, a cell cycle-related protein, using a variety of fixation and immunostaining procedures. The best fixative for PCNA was found to be buffered formaldehyde solution at 4°C followed by methanol at 20°C, whereas alcoholic fixatives decreased greatly the PCNA immunoreactivity. Air-drying procedures of cytospins prior to and after fixation greatly undermined the PCNA immunostaining. A modified immunoperoxidase method provided a stronger staining of the PCNA-reactive cells than the alkaline phosphatase anti-alkaline phosphatase (APAAP) technique. PCNA immunoreactivity could be maintained up to 2 mo, putting slides in methanol at ? 2°C. In conclusion, our report indicates that PCNA is a labile antigen, which may critically be affected by temperature and air-drying procedures. © 1994 Wiley-Liss, Inc.     

Proliferating cell nuclear antigen (PCNA) expression in formalin-fixed tissue of non-small cell lung carcinoma

An immunohistochemical study of non-small cell lung carcinoma using PC10, a monoclonal antibody against PCNA, was performed on tissues routinely processed with formalin fixation and paraffin embedding. The PCNA labelling index and mitotic index were determined from sections of these tissues. Tumours showed a high mean PCNA labelling index of 53.3%. The mean mitotic index was 10.3/1000 cells. Inter-examiner agreement of mitotic counting was good. A linear correlation between the PCNA labelling index and mitotic index was demonstrated (r = 0.71, P less than 0.00001). It is concluded that immunohistochemical nuclear labelling with anti-PCNA on routinely processed tissue is a simple technique for the assessment of proliferation in non-small cell lung carcinoma.     

The prognostic importance of the nucleolar organizer region (AgNOR), Ki-67 and proliferating cell nuclear antigen (PCNA) in primary nonurachal bladder adenocarcinoma

The aim of this study was to investigate the role of tumor proliferation in patients with nonurachal bladder adenocarcinoma. Samples were obtained from 16 patients (12 men and 4 women, mean age 62 years) with primary nonrurachal bladder adenocarcinoma. The 16 formalin-fixed specimens were stained immunohistochemically for Ki-67 antigen and PCNA using MIB-1 and PC-10 antibodies. In addition, the AgNOR quantity was assessed using the colloid silver nitrate staining technique in all cases. The Ki-67, PCNA and AgNOR proliferation indices were found to be significantly higher in high-grade and invasive tumors. The higher the grade (p<0.01) and stage (p<0.01), the higher were the proliferation indices. Patients whose tumor samples had a high Ki-67, PCNA and AgNOR proliferation index showed a higher incidence of local recurrence (p<0.01) and distant metastasis (p<0.01). In conclusion, our results suggest that Ki-67, PCNA and AgNOR proliferation scores may be important prognostic indices in nonurachal bladder adenocarcinomas.     

Expression of proliferating cell nuclear antigen (PCNA) and Ki-67 in unicystic ameloblastoma

The expression of proliferating cell nuclear antigen (PCNA) and Ki-67 was studied in unicystic and solid ameloblastoma (follicular and plexiform types) using a biotin-streptavidin method on routinely processed paraffin sections. To determine percentage PCNA and Ki-67 labelling indices, positive tumour cells and total tumour cells were counted in areas of each unicystic ameloblastoma corresponding to cystic linings, intraluminal nodules and invading tumour islands, and in solid ameloblastomas. Positive cells in basal and suprabasal layers of cystic tumour lining were also counted with respect to the length of basement membrane determined by image analysis. In unicystic ameloblastoma the invading islands exhibited a significantly higher PCNA labelling index (29.2 ± 16.4%) than intraluminal nodules (13.6 ± 5.4%; P < 0.05). Cystic tumour lining had relatively few PCNA positive cells and a labelling index (5.5 ± 3.3%) significantly lower than invading islands (P < 0.001) or intraluminal nodules (P < 0.003). The labelling indices of solid ameloblastomas of follicular type (48.1 ± 12.9%) were significantly higher than those of cystic tumour lining (P < 0.0001), intraluminal nodules (P < 0.001) and invading islands (P < 0.04) in unicystic ameloblastoma. Similar relationships were found for Ki-67 expression except that comparisons involving invading islands and intraluminal nodules were not significant, a finding probably due to the smaller number of specimens available for quantitative analysis. These results indicate differences in proliferative potential between different areas of unicystic ameloblastoma and between unicystic and solid lesions. The fact that invading tumour islands within the fibrous tissue wall showed high labelling indices is in agreement with the clinical observation that their presence may be related to recurrence after conservative surgery. This provides a biological basis for indicating more radical surgical excision as the treatment of choice for this subgroup of lesions.     

Induction of proliferating cell nuclear antigen and Ki-67 expression by cytomegalovirus infection

With the goal of facilitating viral reproduction, cytomegalovirus (CMV) induces changes in the host cell replication machinery. Very little information is available, however, on the effects brought about by CMV on proliferating cell nuclear antigen (PCNA) and Ki-67 expression in infected cells. Fifty-five paraffin-embedded tissue samples (43 gastrointestinal, 10 skin, and 2 kidney biopsies) with both histological and immunohistochemical evidence of CMV infection were investigated for PCNA and Ki-67 expression by the avidin– biotin–peroxidase method. Of the 55 cases studied, 47 were positive for PCNA and 46 for Ki-67. PCNA and Ki-67 immunostaining was more striking in CMV-immunoreactive, inclusion-free cell nuclei, whereas cell nuclei exhibiting well-developed CMV inclusions either showed a weak peripheral signal for both proliferation markers, or were completely negative. Enhanced PCNA and Ki-67 expression appears to be among the changes induced by CMV infection in host cells. Moreover, this induction seems to reach its peak during the earlier phases of CMV infection and abate as the infection proceeds to its inclusion-forming phases, when a sufficiently high viral load would have been attained. © 1998 John Wiley & Sons, Ltd.     

P53 and proliferating cell nuclear antigen (PCNA) expression in non-tumoral liver diseases

The tumor suppressor gene p53 is known to be involved in the negative regulation of cell growth. Proliferating cell nuclear antigen (PCNA), which is a nuclear protein and a component of the DNA replication process, is also involved in growth regulation. Both have been studied as progression markers in various tumors including hepatocellular carcinoma. In the present study, the aberrant p53 protein and PCNA expressions in non-tumoral liver diseases were investigated. Using monoclonal antibodies anti-p53 (D07-DAKO) and anti-PCNA (PC10-DAKO), 149 samples were stained, including 10 normal and 10 tumoral control liver tissues. p53 Overexpression was detected in 52 specimens (35%) whereas PCNA positivity was found in 96 (64%). There were 21 different pathological entities but most of the positive samples could be grouped into four types of diseases; namely, non-specific reactive hepatitis, steatohepatitis, chronic hepatitis and cirrhosis. Statistical analyses performed on these groups revealed that p53 positivity was found to be significantly higher in steatohepatitis (P < 0.05), while PCNA positivity did not show any statistical significance. The number of samples showing both p53 and PCNA positivity was 42 but their coexistence was not found to be significant. Certain cytological alterations like nuclear pleomorphism, steatosis and cholestasis, in addition to necroinflammatory activity, were evaluated for their possible impact on p53 and/or PCNA positivity. Necroinflammatory activity in steatohepatitis and steatosis in chronic hepatitis was found to be significant for p53 positivity (P < 0.05). In contrast, nuclear pleomorphism in non-specific reactive hepatitis was found to be significant for PCNA positivity (P < 0.05).     

A comparison of proliferating cell nuclear antigen (PCNA) immunostaining, nucleolar organizer region (AgNOR) staining, and histological grading in gastrointestinal stromal tumours.

Gastrointestinal stromal tumours are lesions in which it is difficult to predict clinical outcome from the histological appearances. Sixty cases were studied using three different methods of assessing aspects of cellular proliferation; these were (i) immunostaining for proliferating cell nuclear antigen (PCNA), (ii) interphase nucleolar organizer region staining (AgNORs), and (iii) a histological grading system based on mitotic counts. Both PCNA immunostaining and AgNOR counts were found to correlate well with histological grading and all three methods independently showed good correlations with survival. This suggests that these proliferation-associated markers may be used as additional features to support histological grading in this relatively uncommon group of tumours.     

Ovarian follicle counts using proliferating cell nuclear antigen (PCNA) and semi-automated image analysis in rats

Ovarian follicle counting is a method to assess ovarian toxicity in reproductive toxicity studies in rats. Although ovarian follicle counting has been traditionally performed manually on hematoxylin and eosin (H&E)-stained sections, the use of immunohistochemical methods, including human cytochrome P450 1B1 (CYP1B1) and proliferating cell nuclear antigen (PCNA), have been used to enhance the visibility of the primordial and primary follicles to facilitate manual counting. In this study, serial sections from both ovaries from ten 3-month-old female Sprague Dawley rats were stained using routine H&E and immunohistochemistry for PCNA. Counting of primordial and primary follicles was performed manually using these two stains and by semi-automated image analysis of PCNA-stained slides. Although manual counting of PCNA-stained slides is preferable to manual counting of H&E-stained slides, manual counting involves variability between individual counters. Semi-automated image analysis of PCNA-stained slides yields an accurate and consistent count of these primordial/primary follicles and eliminates variability between individual counters.     

Sequential induction of Hsp25 and proliferating cell nuclear antigen in the kidney after burn

Burn injury elicits a wide range of intracellular signaling events leading to alterations in phenotypes of distant organs. Renal dysfunction is one of several serious postburn complications. To better understand the underlying mechanisms of renal dysfunction among burn patients, we investigated alterations in the expression of heat shock proteins (Hsps) and cell cycle-associated proteins in the kidney after burn. Following an approximately 18% total body surface area burn, blood and kidney samples were harvested from mice at several time points. Serum levels of blood urea nitrogen increased significantly at 3 h and returned to basal levels at Day 1 implying a transient dysfunction of glomerular filtration. The expression of Hsp25 was increased at Day 1, whereas no changes in Hsp70 expression were observed. An increase in proliferating cell nuclear antigen (PCNA), a marker of cell proliferation, peaked at Day 3, and its expression was predominantly limited to cells appearing to be tubular epithelial cells in the cortex. In contrast, no significant alterations in the p21 mitosis inhibitor were noted. Furthermore, increases in histones H1 and H2A at Day 3 paralleled the PCNA induction suggesting a burn-mediated alteration in cell cycle activities. The results from this study suggest that a sizeable burn may trigger sequential activation of signaling events involved in the early pathogenesis and subsequent recovery of the kidney after burn.