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

Current understanding of the genomic abnormities in premature ovarian failure: chance for early diagnosis and management

Premature ovarian failure (POF) is an insidious cause of female infertility and a devastating condition for women. POF also has a strong familial and heterogeneous genetic background. Management of POF is complicated by the variable etiology and presentation, which are generally characterized by abnormal hormone levels, gene instability and ovarian dysgenesis. To date, abnormal regulation associated with POF has been found in a small number of genes, including autosomal and sex chromosomal genes in folliculogenesis, granulosa cells, and oocytes. Due to the complex genomic contributions, ascertaining the exact causative mechanisms has been challenging in POF, and many pathogenic genomic characteristics have yet to be elucidated. However, emerging research has provided new insights into genomic variation in POF as well as novel etiological factors, pathogenic mechanisms and therapeutic intervention approaches. Meanwhile, scattered studies of transcriptional regulation revealed that ovarian cell function also depends on specific biomarker gene expression, which can influence protein activities, thus causing POF. In this review, we summarized the latest research and issues related to the genomic basis for POF and focused on insights gained from their biological effects and pathogenic mechanisms in POF. The present integrated studies of genomic variants, gene expression and related protein abnormalities were structured to establish the role of etiological genes associated with POF. In addition, we describe the design of some ongoing clinical trials that may suggest safe, feasible and effective approaches to improve the diagnosis and therapy of POF, such as Filgrastim, goserelin, resveratrol, natural plant antitoxin, Kuntai capsule et al. Understanding the candidate genomic characteristics in POF is beneficial for the early diagnosis of POF and provides appropriate methods for prevention and drug treatment. Additional efforts to clarify the POF genetic background are necessary and are beneficial for researchers and clinicians regarding genetic counseling and clinical practice. Taken together, recent genomic explorations have shown great potential to elucidate POF management in women and are stepping from the bench to the bedside.

Bioinformatics analysis of the prognostic biomarkers and predictive accuracy of differentially expressed genes in high-risk multiple myeloma based on Gene Expression Omnibus database mining

Background

Multiple myeloma (MM) is still an intractable disease for modern clinical system, and more researches are necessary for development of more effective therapeutic strategies. This study attempted to screen and validates the biomarkers in the progression of MM via excavating Gene Expression Omnibus (GEO) database. Identification of a biomarker may help not only facilitate early diagnosis and management but also identify individuals at risk for poor prognosis and development of MM.

Methods

The mRNA expression profile of the GSE87900 dataset was analyzed by GEO2R. Using the SangerBox online program, differentially expressed genes (DEGs) in high-risk MM samples were screened with the filter criteria of P<0.05 and |logFC| >1. The SangerBox online analysis tool was used to analyze the volcano plot. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis was performed for DEGs. Twenty patients with high-risk MM and 20 patients with standard-risk MM from Taian City Central Hospital were included. Real-time quantitative polymerase chain reaction (RT-qPCR) was used to verify the selected key genes in MM tissues.

Results

A total of 611 DEGs were obtained. GO functional enrichment analysis showed that the DEGs were mainly enriched in the DNA replication process at the biological level, and the top DEGs were CACYBP, PCNA, MCM6, SMC1A, DTL, GINS4, MCM2, CDT1, RRM2, BRCA1, RFC5, MCM4, GINS3, GINS1, MCM10, CDC7, CDAN1, BRIP1, GINS2, CDK1, NFIB, and BARD1. The expression of CDC7 and PCNA was significantly different in high-risk MM and standard-risk MM as determined by RT-qPCR. Receiver operating characteristic (ROC) analysis showed that the areas under the curve predicted by CDC7 and PCNA were 0.900 and 0.8863, respectively, which allowed the identification of CDC7 and PCNA could be a potential biomarker of MM. Kaplan-Meier survival analysis showed that MM patients with high CDC7 and PCNA expression had shorter 2-year overall survival (OS) (P<0.05).

Conclusions

CDC7 and PCNA can be used as biomarkers for the prognosis of high-risk MM and evaluate the prognosis of MM patients, which is helpful for guiding the clinical treatment of MM patients.

Proliferating cell nuclear antigen presentation, as a marker of folliculogenesis, in the transplanted ovarian tissue

AIM

One of the most important ways to understand the ovarian biology is studding the initiation of primordial follicle development and subsequent folliculogenesis control. In this study, proliferating cell nuclear antigen (PCNA) presentation was used as a marker of follicular development in the thawed ovarian tissue (OT) following transplantation onto chick embryo chorioallantoic membrane (CAM) using two methods of freezing of slow freezing and vitrification.

METHODS

Samples of OT from 10 patients were subjected to slow freezing and vitrification. After warming, CAM transplantation was done and PCNA proliferation index (PI; percent of PCNA-positive granulosa cells) was calculated for each follicle stage. Image J software was used to determine the mean staining intensity.

RESULTS

PCNA was positive for granulosa cells and oocytes nuclei, but negative for ooplasm. There were no remarkable PCNA staining in the granulosa cells of primordial follicles, but increased significantly as follicle progression (p < 0.05). Proliferation rate was also insignificantly higher in the vitrified than slow freezing group, before and after transplantation (p < 0.05). Lower PCNA presentation index was observed after CAM transplantation (p < 0.05). The earliest stage of follicular recruitment took place in the transitional follicles, before squamous cells transform to cuboidal cells.

CONCLUSION

PCNA showed that follicles had proliferation power after cryopreservation. Higher presentation after vitrification may indicate accelerated folliculogenesis in the thawed OT.

An Overview of Candidate Therapeutic Target Genes in Ovarian Cancer

Ovarian cancer (OC) shows the highest mortality rate among gynecological malignancies and, because of the absence of specific symptoms, it is frequently diagnosed at an advanced stage, mainly due to the lack of specific and early biomarkers, such as those based on cancer molecular signature identification. Indeed, although significant progress has been made toward improving the clinical outcome of other cancers, rates of mortality for OC are essentially unchanged since 1980, suggesting the need of new approaches to identify and characterize the molecular mechanisms underlying pathogenesis and progression of these malignancies. In addition, due to the low response rate and the high frequency of resistance to current treatments, emerging therapeutic strategies against OC focus on targeting single factors and pathways specifically involved in tumor growth and metastasis. To date, loss-of-function screenings are extensively applied to identify key drug targets in cancer, seeking for more effective, disease-tailored treatments to overcome lack of response or resistance to current therapies. We review here the information relative to essential genes and functional pathways recently discovered in OC, often strictly interconnected with each other and representing promising biomarkers and molecular targets to treat these malignancies.

Beyond the Biomarker: Understanding the Diverse Roles of Human Epididymis Protein 4 in the Pathogenesis of Epithelial Ovarian Cancer

Human epididymis protein 4 (HE4) is an important clinical biomarker used for the detection of epithelial ovarian cancer (EOC). While much is known about the predictive power of HE4 clinically, less has been reported regarding its molecular role in the progression of EOC. A deeper understanding of HE4’s mechanistic functions may help contribute to the development of novel targeted therapies. Thus far, it has been difficult to recommend HE4 as a therapeutic target owing to the fact that its role in the progression of EOC has not been extensively evaluated. This review summarizes what is collectively known about HE4 signaling and how it functions to promote tumorigenesis, chemoresistance, and metastasis in EOC, with the goal of providing valuable insights that will have the potential to aide in the development of new HE4-targeted therapies.

The Value of Cell Proliferation and Angiogenesis in the Prognostic Assessment of Ovarian Granulosa cell Tumors

Objectives

Most cases of granulosa cell tumors (GCT) of the ovary are characterized by a relatively good outcome. However, some tumors behave aggressively and some tend to recur many years after the initial diagnosis. Tumor growth depends on cell proliferation and angiogenesis. Thus, proliferative indices and microvessel density were studied to determine possible valuable methods to assess the GCT patient's outcome.

Methods and study design

Paraffin-embedded tissue blocks were available for 60 patients with primary GCT and were investigated by immunostaining with monoclonal antibodies against PCNA, Ki-67 and factor VIII-related antigen. The follow-up was available for 51 patients and ranged from 25 to 206 months. A clinical follow-up distribution of patients was made: 8 patients with recurrence (group I); 6 patients who lived with no evidence of recurrence for 100 months or more (group II), and 37 patients alive with no evidence of recurrence in the follow-up period of less than 100 months (group III).

Results

There was a statistical correlation between PCNA and Ki-67 proliferative indices. A significant increase (P «0.05) of mean PCNA and Ki-67 proliferative indices and mean tumor size was seen in patients of Group I compared to those of Group II. The mean PCNA proliferative index positively correlated with the mean Ki-67 proliferative index for Groups I and II. Mean microvessel density showed a positive correlation with mean PCNA and Ki-67 proliferative indices and with mean tumor size for Group I, whereas it was negatively correlated with PCNA proliferative index and tumor size for Group II. A positive correlation was found between mean mitotic count and both proliferative indices only for Group II. The following features were indicative of a relatively poor prognosis: GCT measuring >9 cm in diameter, PCNA >4.0%, Ki-67 >1.2%, and diffuse, insular and sarcomatoid histologic patterns.

Conclusions

The findings support the importance of proliferative factors, tumor size and histologic patterns as possible prognostic indicators for estimating the biologic behavior of patients with GCT. Unfortunately, angiogenesis did not seem to be a useful determinant parameter of a possible aggressive behavior. However, a longer follow-up period with larger series may be required to assess the value of the parameters in prediction of patient survival.

Flow Cytometric and Immunohistochemical Correlations in High Incidence Human Solid Tumors

475 patients with carcinoma at different sites (141 colon-rectum; 102 breast; 50 stomach; 48 kidney; 46 head and neck; 41 bladder; 47 other sites) submitted to surgery have been analyzed after histopathological staging and grading, by flow cytometry (monoparametric DNA content analysis) and immunohistochemistry (p53, c-erbB-2, and PCNA expression). In breast cancer patients the presence of receptors for estrogen (ER) and progesterone (PGR) has also been determined. Flow cytometry-derived parameters were DNA ploidy, fraction of cells in S-phase (SPF), and DNA content heterogeneity (multiclonal stem cell lines with different DNA index and/or more than one subpopulations with different ploidy levels in different samples from the same tumor). Correlations of the results obtained by the different techniques have been attempted by the non-parametric Spearman's rank correlation approach. Significant associations (P «0.05) were found between the histopathological, immunohistochemical and flow cytometric parameters considered in some anatomical regions, such as stomach (p53 vs DNA content aneuploidy and vs heterogeneity), colon-rectum (TNM vs p53 and vs heterogeneity), bladder (grading vs DNA content aneuploidy and vs heterogeneity). Tumor heterogeneity proved to be dependent on the number of tumor samples taken. The results of this preliminary assessment will subsequently be compared with the data obtained from a currently ongoing follow-up survey.

Targeted proteomic assays for quantitation of proteins identified by proteogenomic analysis of ovarian cancer

Mass spectrometry (MS) based targeted proteomic methods such as selected reaction monitoring (SRM) are emerging as a promising tool for verification of candidate proteins in biological and biomedical applications. The Clinical Proteomic Tumor Analysis Consortium (CPTAC) of the National Cancer Institute has investigated the standardization and analytical validation of the SRM assays and demonstrated robust analytical performance on different instruments across different laboratories. An Assay Portal has also been established by CPTAC to provide the research community a resource consisting of large sets of targeted MS-based assays, and a depository to share assays publicly. Herein, we report the development of 98 SRM assays that have been thoroughly characterized according to the CPTAC Assay Characterization Guidance Document; 37 of these passed all five experimental tests. The assays cover 70 proteins previously identified at the protein level in ovarian tumors. The experiments, methods and results for characterizing these SRM assays for their MS response, repeatability, selectivity, stability, and endogenous detection are described in detail. Data are available via PeptideAtlas, Panorama and the CPTAC Assay Portal.

Bidirectional Estrogen-Like Effects of Genistein on Murine Experimental Autoimmune Ovarian Disease

This study was to investigate the bidirectional estrogen-like effects of genistein on murine experimental autoimmune ovarian disease (AOD). Female BALB/c mice were induced by immunization with a peptide from murine zona pellucida. The changes of estrous cycle, ovarian histomorphology were measured, and the levels of serum sex hormone were analyzed using radioimmunoassay. Proliferative responses of the ovary were also determined by immunohistochemistry. Administration of 25 or 45 mg/kg body weight genistein enhanced ovary development with changes in serum sex hormone levels and proliferative responses. Meanwhile, the proportions of growing and mature follicles increased and the incidence of autoimmune oophoritis decreased, which exhibited normal ovarian morphology in administration of 25 or 45 mg/kg body weight genistein, while a lower dose (5 mg/kg body weight genistein) produced the opposite effect. These findings suggest that genistein exerts bidirectional estrogen-like effects on murine experimental AOD, while a high dose (45 mg/kg body weight) of genistein may suppress AOD.

PIK3R3 induces epithelial-to-mesenchymal transition and promotes metastasis in colorectal cancer

Class IA PI3K plays an essential role in the invasion and metastasis of cancer. However, the mechanisms and specific functions of PI3K isoforms in tumor invasion and metastasis are not fully understood. We evaluated the role of PIK3R3, a PI3K regulatory subunit encoded by the PIK3R3 gene, in colorectal cancer invasion and metastasis. Clinical specimens and cell lines data show that the expression level of PIK3R3 is associated with colorectal cancer metastasis. Overexpression of PIK3R3 increases tumor migration and invasion in vitro and promotes metastasis of colorectal cancers in vivo. Furthermore, we investigated that the overexpression of PIK3R3 depends on SNAI2, inducing significant epithelial-to-mesenchymal transition (EMT). Downregulation of PIK3R3 reverses this process, which possibly contributes to the enhanced invasive and metastasizing abilities of colorectal cancer cells. In this study, we found that PIK3R3 plays an important role in colorectal cancer metastasis and might be a potential and specific target for therapies against metastatic colorectal cancer.

Apoptosis and cell proliferation correlated with tumour grade in peritoneal fluids of patients with serous ovarian cancer

OBJECTIVE

Apoptosis and cell proliferation in peritoneal fluids of patients with ovarian serous adenocarcinoma have not been well described in cytology. To investigate the contribution of cell death to the growth of this tumour we analysed both apoptosis and cell proliferation in peritoneal fluids of patients with ovarian serous adenocarcinoma.

METHODS

We studied 40 tumours from 40 patients with ovarian serous adenocarcinoma. Twelve tumours were high grade, 13 were moderately differentiated and 15 were poorly differentiated. The detection of DNA fragments in situ using the terminal deoxyribonucleotidy transferase (TDT)-mediated dUTP-digoxigenin nick-end labelling (TUNEL) assay was applied to investigate active cell death (apoptosis), and the MIB-1 antigen was used to investigate cell proliferation.

RESULTS

The TUNEL indices were 0.29 ± 0.05, 0.79 ± 0.10 and 2.1 ± 0.90 in Grade I, Grade II and Grade III ovary carcinomas, respectively. The MIB-1 antigen labelling indices were 6.5 ± 0.09, 12.9 ± 3 and 25.8 ± 6.2, respectively, in the same order of tumour differentiation. The differences in both TUNEL and MIB-1 labelling indices were statistically significant between Grade I, Grade II and Grade III carcinomas and there was a positive correlation between the two indices (P < 0.001).

CONCLUSIONS

Apoptosis and cell proliferation increased as the grade of tumour increased in ovarian serous adenocarcinoma, suggesting a rapid turnover of the tumour cells in tumours of higher grade, and may play an important role in the growth and the extension of such cancer cells in the peritoneal cavity.

A novel biomarker for the detection of esophageal adenocarcinoma

OBJECTIVES

Proliferating cell nuclear antigen is a component of the DNA synthesome and functions in DNA replication and repair. Our group has recently identified an acidic isoform of proliferating cell nuclear antigen, cancer-specific proliferating cell nuclear antigen, that appears to be present only in malignant tissue. We sought to determine the presence of cancer-specific proliferating cell nuclear antigen in esophageal dysplasias and invasive adenocarcinomas to assess its potential utility in discriminating malignancy.

METHODS

With a polyclonal antibody to cancer-specific proliferating cell nuclear antigen, immunohistochemical staining was performed on samples from a total of 30 patients with Barrett esophagus with varying degrees of dysplasia and 18 patients with invasive adenocarcinoma. We also performed cancer-specific proliferating cell nuclear antigen immunohistochemical staining on a commercially available tissue microarray and on specimens obtained from endoscopic biopsies. As controls, immunohistochemical staining for cancer-specific proliferating cell nuclear antigen was performed on normal esophageal tissue and immunohistochemical staining for proliferating cell nuclear antigen was performed on all specimens with a commercially available antibody.

RESULTS

Of the Barrett esophagus specimen, 14 showed no dysplasia, 8 showed low-grade dysplasia, and 8 showed high-grade dysplasia. None of these specimens stained positively for cancer-specific proliferating cell nuclear antigen. Of the 18 adenocarcinoma specimens, all stained positively for cancer-specific proliferating cell nuclear antigen. There was no significant cancer-specific proliferating cell nuclear antigen expression in normal esophageal tissue, and proliferating cell nuclear antigen expression was noted to a high degree in all tissues.

CONCLUSIONS

Cancer-specific proliferating cell nuclear antigen appears to demonstrate high specificity for esophageal adenocarcinoma. This marker therefore may prove useful in differentiating invasive cancer from high-grade dysplasia. Cancer-specific proliferating cell nuclear antigen also holds future promise as a biomarker for esophageal adenocarcinoma.

Proliferative activity of early ovarian clear cell adenocarcinoma depends on association with endometriosis

OBJECTIVE

To investigate differences in the biological characteristics of ovarian clear cell adenocarcinoma based on the presence/absence of endometriosis and tumor proliferative activity.

METHODS

Stage I ovarian clear cell adenocarcinoma patients were divided into groups with and without endometriosis, and immunohistochemical expression of proliferating cell nuclear antigen was determined in surgical specimens. Then xenograft models of human ovarian clear cell adenocarcinoma with or without human ectopic endometrium were created in severe combined immunodeficiency mice, and tumor growth was assessed from the wet weight and the bromodeoxyuridine uptake. Furthermore, a xenograft model of human endometriosis was made with or without ovarian clear cell adenocarcinoma and cytokine production was investigated.

RESULTS

The proliferating cell nuclear antigen labeling index was significantly lower in the tumors of patients with endometriosis compared to the tumors of patients without endometriosis. In tumor-bearing mice, the tumor weight and bromodeoxyuridine uptake were both significantly lower when ovarian clear cell adenocarcinoma was associated with endometriosis than in its absence. Release of transforming growth factor-beta1 and interleukin-6 from the ectopic human endometrium was greater in the presence of clear cell adenocarcinoma than without it, and transforming growth factor-beta1 levels showed a significant difference.

CONCLUSION

The proliferative activity of early ovarian clear cell adenocarcinoma seems to depend on the association of this cancer with endometriosis. When endometriosis is associated with ovarian clear cell adenocarcinoma, there is a change of its cytokine production that may inhibit tumor growth.

The prognostic value of proliferating cell nuclear antigen (PCNA) and p53 protein expression in patients with advanced nasopharyngeal carcinoma

CONCLUSION

p53 protein and proliferating cell nuclear antigen (PCNA) were not ideal prognostic indicators in advanced nasopharyngeal carcinoma (NPC). Further investigation in searching for other potential biomarkers is needed to enhance the prediction of treatment outcome.

OBJECTIVE

To assess the prognostic significance of p53 protein and PCNA expression in patients with advanced NPC.

PATIENTS AND METHODS

This study included 46 patients with advanced NPC who had received treatment and regular follow-up for at least 5 years. We used immunohistochemistry (IHC) staining to assess p53 protein expression and PCNA labeling index, and correlate them with pathological subtypes, TNM stage, the presence of locoregional recurrence, and 5-year survival rate.

RESULTS

p53 nuclear staining was positive in 32 patients (69.6%). All cases had positive PCNA nuclear staining with labeling index (LI) ranging from 6.5% to 92.9% (mean 53.4%). Only advanced T stage was found to be associated with high PCNA LI. Overexpression of p53 and PCNA LI had no impact on 5-year survival in this study group.

Molecular profiling of platinum resistant ovarian cancer

The aim of this study is to discover a gene set that can predict resistance to platinum-based chemotherapy in ovarian cancer. The study was performed on 96 primary ovarian adenocarcinoma specimens from 2 hospitals all treated with platinum-based chemotherapy. In our search for genes, 24 specimens of the discovery set (5 nonresponders and 19 responders) were profiled in duplicate with 18K cDNA microarrays. Confirmation was done using quantitative RT-PCR on 72 independent specimens (9 nonresponders and 63 responders). Sixty-nine genes were differentially expressed between the nonresponders (n=5) and the responders (n=19) in the discovery phase. An algorithm was constructed to identify predictive genes in this discovery set. This resulted in 9 genes (FN1, TOP2A, LBR, ASS, COL3A1, STK6, SGPP1, ITGAE, PCNA), which were confirmed with qRT-PCR. This gene set predicted platinum resistance in an independent validation set of 72 tumours with a sensitivity of 89% (95% CI: 0.68-1.09) and a specificity of 59% (95% CI: 0.47-0.71)(OR=0.09, p=0.026). Multivariable analysis including patient and tumour characteristics demonstrated that this set of 9 genes is independent for the prediction of resistance (p<0.01). The findings of this study are the discovery of a gene signature that classifies the tumours, according to their response, and a 9-gene set that determines resistance in an independent validation set that outperforms patient and tumour characteristics. A larger independent multicentre study should further confirm whether this 9-gene set can identify the patients who will not respond to platinum-based chemotherapy and could benefit from other therapies.

Angiotensin II type 1 receptor expression in ovarian cancer and its correlation with tumour angiogenesis and patient survival

Angiotensin II, a main effector peptide in the renin–angiotensin system, acts as a growth-promoting and angiogenic factor via type 1 angiotensin II receptors (AT₁R). We have recently demonstrated that angiotensin II enhanced tumour cell invasion and vascular endothelial growth factor (VEGF) secretion via AT₁R in ovarian cancer cell lines in vitro. The aim of the present study was to determine whether AT₁R expression in ovarian cancer is correlated with clinicopathological parameters, angiogenic factors and patient survival. Immunohistochemical staining for AT₁R, VEGF, CD34 and proliferating cell nuclear antigen (PCNA) were analysed in ovarian cancer tissues (n=67). Intratumour microvessel density (MVD) was analysed by counting the CD34-positive endothelial cells. Type 1 angiotensin II receptors were expressed in 85% of the cases examined, of which 55% were strongly positive. Type 1 angiotensin II receptors expression was positively correlated with VEGF expression intensity and MVD, but not with histological subtype, grade, FIGO stage or PCNA labelling index. In patients who had positive staining for AT₁R, the overall survival and progression-free survival were significantly poor (P=0.041 and 0.017, respectively) as compared to those in patients who had negative staining for AT₁R, although VEGF, but not AT₁R, was an independent prognostic factor on multivariate analysis. These results demonstrated that AT₁R correlated with tumour angiogenesis and poor patient outcome in ovarian cancer, suggesting its clinical potential for a novel molecular target in strategies for ovarian cancer treatment.

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.

Expression profiling of serous low malignant potential, low-grade, and high-grade tumors of the ovary

Papillary serous low malignant potential (LMP) tumors are characterized by malignant features and metastatic potential yet display a benign clinical course. The role of LMP tumors in the development of invasive epithelial cancer of the ovary is not clearly defined. The aim of this study is to determine the relationships among LMP tumors and invasive ovarian cancers and identify genes contributing to their phenotypes. Affymetrix U133 Plus 2.0 microarrays (Santa Clara, CA) were used to interrogate 80 microdissected serous LMP tumors and invasive ovarian malignancies along with 10 ovarian surface epithelium (OSE) brushings. Gene expression profiles for each tumor class were used to complete unsupervised hierarchical clustering analyses and identify differentially expressed genes contributing to these associations. Unsupervised hierarchical clustering analysis revealed a distinct separation between clusters containing borderline and high-grade lesions. The majority of low-grade tumors clustered with LMP tumors. Comparing OSE with high-grade and LMP expression profiles revealed enhanced expression of genes linked to cell proliferation, chromosomal instability, and epigenetic silencing in high-grade cancers, whereas LMP tumors displayed activated p53 signaling. The expression profiles of LMP, low-grade, and high-grade papillary serous ovarian carcinomas suggest that LMP tumors are distinct from high-grade cancers; however, they are remarkably similar to low-grade cancers. Prominent expression of p53 pathway members may play an important role in the LMP tumor phenotype.

Characterisation of the progression of azaserine-induced rat pancreatic adenocarcinoma by proliferative cell nuclear antigen, basement membrane laminin and trypsinogen immunohistochemistry

The progression of azaserine-induced rat pancreatic adenocarcinoma (AC) was characterised using quantitative and semiquantitative immunohistochemistry for proliferating cell nuclear antigen (PCNA), basement membrane laminin (BML) and trypsinogen (TG). Samples were taken 5-20 months after initiation. High PCNA-labelling indices (PCNA LIs) were measured 5 months after the induction of atypical acinar cell nodules (AACNs), which decreased later and stagnated until a further decline in the month 10 adenomas. Then a second premalignant proliferative wave was observed (month 13) within the adenoma stage. Later, in month 20 differentiated ACs PCNA LIs fell to the host tissue level but were found highest in the month 20 anaplastic ACs indicating a switch to malignant proliferation. Month 20 invasive ACs showed a number of separate proliferative foci. In early AACNs, BML decreased and remained low till the local maximum in the month 13 adenoma. Invasive ACs did not express BML. Month 5 AACN and differentiated AC were TG deficient but anaplastic AC regained its TG expression. However invasive AC was again TG negative. These results are discussed in combination with our previous data on progressional changes of autophagic capacity and microvessel densities.

Expression of polo-like kinase in ovarian cancer is associated with histological grade and clinical stage

Polo-like kinase (PLK), a cell cycle-regulated, cyclin-independent serine/threonine protein kinase, has been shown in recent reports to play a critical role during tumorigenesis. To investigate whether PLK plays a general role as a tumor marker of ovarian cancers, we examined the expression of PLK protein in ovarian cancers, and analyzed the relationship between PLK protein expression and histological grade. Immunohistochemically, the majority of PLK was found in the cytoplasm (around the nucleus), and a portion was found in the nucleus of ovarian cancer glands and also in the fluid secreted from these glands. PLK was expressed at the basement membrane of cancer glands and partly expressed in the head portion of papillary cancer tissues. A significant correlation was found between percentages of PLK-positive cells and histological grade of ovarian cancer (P<0.001). However, the expression of proliferating cell nuclear antigen, Ki-67, and cyclin B1 was independent of PLK expression. Taken together, these findings suggest that PLK expression may reflect the degree of malignancy rather than the degree of proliferation in ovarian cancer. Thus, in addition to being of diagnostic value, PLK activity in ovarian tumors may be modulated by chemotherapeutic agents or gene therapy to therapeutic effect.

p53 and related proteins in epithelial ovarian cancer

We conducted a retrospective immunohistochemical evaluation of the prognostic significance of the expression of p53 and the related proteins Bax, Bcl-2, growth arrest and DNA damage (Gadd45), murine double minute 2 (Mdm2) and p21(WAF1/CIP1) in chemonaive tumours taken from 66 patients with ovarian cancer. Ki-67 expression (a marker of cell proliferation) was also evaluated immunohistochemically, while apoptosis within malignant cells was determined with the terminal deoxynucleotidyltransferase-mediated dUTP nick-end labelling (TUNEL) assay. The expression of each of the following proteins was significantly associated in the tumours (P < 0.05 unless otherwise stated): Bax with Bcl-2 (P < 0.01); Bax with Mdm2; p21(WAF1/CIP1) with Gadd45 (P < 0.01); p21(WAF1/CIP1) with p53; p53 with Mdm2. Univariate analysis showed that expression of p53, Bax, bulk residual disease and International Federation of Gynecology and Obstetricians (FIGO) stage were all strongly correlated with response to chemotherapy (P < 0.01). Similarly, the FIGO stage and Ki-67 expression (P < 0.01), as well as pathological subtype and bulk residual disease (P < 0.05), were prognostic factors for disease progression. The FIGO stage and Ki-67 expression were significant prognostic factors for overall survival (P < 0.01), with Gadd45 expression and pathological subtype also significant (P < 0.05) in a univariate analysis. Multivariate analysis for response to chemotherapy showed that expression of p53, Bax and FIGO stage were all independent prognostic factors (P < 0.01). The FIGO stage was the most important independent prognostic factor for progression and survival on multivariate analysis (P < 0.01). However, Ki-67 expression was also an independent prognostic factor for disease progression (P < 0.05) and approached significance for survival (P = 0.055). Taken together, these data suggest that determination of Ki-67 expression could supplement established prognostic factors.

DNA ploidy analysis and cell proliferation in congenital sacrococcygeal teratomas

BACKGROUND

Congenital sacrococcygeal teratoma is the most common germ cell tumor in infants and children. It usually is diagnosed at birth, is benign, and consists of fully differentiated mature tissues. Congenital sacrococcygeal teratomas (SCTs) also may contain immature tissues, most commonly of neural origin. The proportion of malignant teratomas increases with advancing age, but the relation between mature and immature SCTs is not well understood. Thus, it is very important to determine proliferative activity, DNA ploidy, and DNA index to predict biologic behavior of these tumors.

METHODS

DNA ploidy and cell proliferation were analyzed by flow cytometry, and the expression of proliferating cell nuclear antigen (PCNA) and Ki-67 were analyzed immunohistochemically on paraffin embedded tissue.

RESULTS

All the tumors that were surgically treated within 3 months after birth, including immature teratoma, were diploid. Strongly positive PCNA immunostaining was found in both immature teratomas, and weakly positive PCNA was found in nine cases. Weak positivity for Ki-67 was observed in 2 cases, and moderate positivity was observed in 6 cases including immature teratomas.

CONCLUSION

The value of flow cytometry in the prediction of biologic behavior of congenital SCT should be analyzed further. Our results suggest that Ki-67 and especially PCNA may reflect the proliferative activity of these tumors.

[Proliferating cell nuclear antigen (PCNA) in ovarian carcinoma and its relation to lymph node metastasis and prognosis]

OBJECTIVE

To investigate expression of proliferating cell nuclear antigen (PCNA) in ovarian epithelial cancer and its relation to lymph node metastasis, second-look laparotomy (SLL) and prognosis.

METHODS

Monoclonal antibody PC10 was used to stain PCNA in archival paraffin-embedded tissues.

RESULTS

PC10 immunostaining was performed successfully in all 74 primary and 31 intraperitoneal metastatic tumors. The expression of PCNA was significantly elevated in 31 metastatic tumors compared with their primary tumor from the same patient (7.94 vs 6.89, P = 0.042). The expression was more marked in bilateral than in unilateral ovarian cancer but it was not associated with lymph node metastasis, clinical stage, histologic grade and subtype. In 28 patients with stage III ovarian cancer undergone SLL, the mean immunoreactive score (IRS) of PCNA of the primary tumor was significantly higher in patients with negative SLL than in those with positive SLL (7.59 vs 6.10, P = 0.03). Since chemotherapy was performed following surgical debulking, negative SLL more frequently seen in patients with high PCNA expression might suggest better chemotherapeutic sensitivity due to higher proliferation fraction of tumor cells. Univariate analysis of survival indicated that the overall survival was inversely associated with the level of PCNA expression, while multivariate analysis with Cox's model showed that independent prognostic factors were the residual tumor after primary debulking (P < 0.001) and clinical stage (P < 0.05), followed by PCNA expression (P = 0.09).

CONCLUSION

The expression of PCNA may be useful in predicting prognosis, but is not correlated with lymph node metastasis.

The combined evaluation of p53 accumulation and of Ki-67 (MIB1) labelling index provides independent information on overall survival of ovarian carcinoma patients

BACKGROUND

The prognostic implications of p53 accumulation, bcl-2 immunoreactivity and tumour proliferative fraction in ovarian carcinomas are still debated.

PATIENTS AND METHODS

One hundred twelve ovarian carcinomas were immunostained for p53 protein, for bcl-2 and for the cell cycle-associated Ki-67 antigen. The immunostaining results were correlated with conventional clinico-pathological variables, response to induction chemotherapy, and patient survival.

RESULTS

p53 accumulation and bcl-2 immunoreactivity in more than 10% of neoplastic cells were detected in 61 (54.5%) and 42 (37.5%) cases, respectively. A positive correlation between p53 accumulation and high (more than 30% neoplastic cells) MIB1 labelling index (r = 0.235; P = 0.015) was ascertained, whereas no significant association was found between bcl-2 immunoreactivity and p53 accumulation or MIB1 labeling index. Both p53 accumulation and MIB1 immunoreactivity correlated significantly with a reduced overall survival, but the association was lost in multivariate analysis. However, patients with tumours simultaneously showing p53 accumulation and MIB1 labelling index higher than 30% had significantly reduced overall survivals, in both univariate and multivariate analyses.

CONCLUSION

The simultaneous evaluation of p53 accumulation and MIB1 labelling index has independent prognostic implications in common epithelial malignancies of the ovary, irrespective of the disease stage.

Decrease in tumor volume and histologic response to intraarterial neoadjuvant chemotherapy in patients with cervical and endometrial adenocarcinoma

Our purpose was to evaluate the utility of clinicopathological and biological markers prior to treatment in predicting the immediate response to chemotherapy in cervical and endometrial adenocarcinomas. Twelve patients with locally advanced cervical adenocarcinomas and 16 patients with endometrial adenocarcinomas received intraarterial neoadjuvant chemotherapy (NAC) consisting of cisplatin and doxorubicin before surgical resection. The decrease in tumor volume on magnetic resonance imaging (MRI) ([tumor volume before NAC - tumor volume after NAC]/tumor volume before NAC x 100) and the histologic response to NAC were assessed. Five factors prior to NAC (nuclear grade, pretreatment tumor volume, PCNA index, p53 protein expression, and DNA ploidy) were analyzed for correlation with the decrease in tumor volume and histologic response in cervical and endometrial adenocarcinoma, respectively. In cervical adenocarcinoma, patients with higher PCNA index tumor (> or = 40.2%) showed a significantly greater decrease in tumor volume than those with lower PCNA index (P < 0.05). In patients with endometrial adenocarcinoma, those with a smaller tumors (< 30.3 cm3) showed a significantly greater decrease than those with a larger tumors (P < 0.001). Tumors with higher PCNA index (> or = 31.5%) and negative p53 protein expression appeared to respond better than other tumors, but the difference was not statistically significant. Nuclear grade and DNA ploidy were not correlated with decrease in tumor volume either in cervical adenocarcinoma or in endometrial adenocarcinoma. Four cases of effective histologic response (2 complete responses [no microscopic residual tumor] and 2 marked responses [no macroscopic residual tumor]) were noted only in patients with endometrial adenocarcinoma who had a smaller tumor, higher PCNA index, and negative p53 protein expression. Pretreatment tumor volume and PCNA index were the only significant predictive factors (P < 0.05). Results suggest that the PCNA index in cervical and endometrial adenocarcinomas and the pretreatment tumor volume in endometrial adenocarcinoma appeared to be potentially useful in predicting the immediate response to the chemotherapy.

Differences in cell proliferation and prognostic significance of proliferating cell nuclear antigen and Ki-67 antigen immunoreactivity in in situ and invasive carcinomas of the extrahepatic biliary tract

BACKGROUND

Cell proliferative activity is an important indicator of growth and behavior of various human tumors. Immunostaining of tissue sections with proliferating cell nuclear antigen (PCNA) and Ki-67 antibodies appears to be reliable in the assessment of tumor cell proliferation. This study examined differences in cell kinetics between neoplastic and nonneoplastic lesions of the gallbladder and biliary tract using an antibody against PCNA and Ki-67.

METHODS

There were a total of 27 cancer cases comprising patients with invasive carcinoma of the gallbladder (n = 13), common bile duct (n = 5) and ampulla of Vater (n = 8). Cases of chronic cholecystitis (n = 11) from the nonneoplastic group; carcinoma in situ (CIS) of the gallbladder (n = 4) and ampulla (n = 6) from the noninvasive group. Cell cycle activity was determined in sections of routinely formalin fixed, paraffin processed, biopsy material using immunohistochemical stains for the monoclonal PCNA, PC10, KI-67, and MIB-1. The expression of PCNA and MIB-1 in these conditions was determined by calculating the percentage of cell nuclei that stained positively to obtain the PCNA and MIB-1 indices, respectively.

RESULTS

The PCNA and MIB-1 indices in chronic cholecystitis were significantly lower than those obtained in both moderately and poorly differentiated adenocarcinoma of the gallbladder (P < 0.001). Similarly, cases of ampullary and gallbladder CIS had significantly lower PCNA and MIB-1 indices than the invasive carcinoma cases (P < 0.001). There was a strong correlation between PCNA and MIB-1 expression (r = 0.828, r2 = 0.686; P = 0.001), although the PCNA index was generally higher than that of MIB-1. The poorly differentiated adenocarcinomas of the gallbladder had higher mean PCNA and MIB-1 indices but reduced patient survival when compared with the moderately differentiated carcinomas.

CONCLUSIONS

In conclusion, gallbladder, ampulla, and common bile duct carcinomas have significantly higher PCNA and MIB-1 indices than CIS and nonneoplastic lesions. Because tumors with higher PCNA or MIB-1 indices are associated with a poorer prognosis, both PCNA and MIB-1 may be useful markers of tumor cell proliferative activity and biologic behavior in gallbladder, ampullary, and common bile duct carcinomas.

Immunohistochemical study on the prognostic value of MIB-1 in gastric carcinoma

The prognostic significance of tumour cell proliferation was investigated in a series of 418 gastric carcinomas using the monoclonal antibody MIB-1. Owing to strong intratumoural heterogeneity of MIB-1 expression three different proliferation indices (PIs) were determined in all carcinomas: (1) PImax in areas of maximal tumour cell proliferation, (2) PIrand in areas randomly distributed over the whole tumour. (3) PIfront in areas exclusively located at the tumour invasion front. There was a strong intertumoral heterogeneity with PImax ranging from 4.9% to 92.2%, PIrand ranging from 3.4% to 81.4% and PIfront ranging from 4.2% to 87.1%. The mean values were 51.3% +/- 19.7 for PImax, 34.2% +/- 18.3 for PIrand and 37.2% +/- 19.5 for PIfront. Whereas no statistically significant correlation could be found between proliferative activity and the clinicopathological parameters depth of invasion, lymph node involvement or grade of tumour differentiation, there was a positive correlation between a high proliferation index at the tumour invasion front (PIfront) and the presence of blood or lymphatic vessel invasion. No significant correlation could be demonstrated between the different proliferation indices and survival, even when different subgroups of patients were analysed separately. The present results suggest that the immunohistochemical evaluation of the proliferation activity has no predictive value for the prognosis of gastric cancer patients or the identification of subgroups of patients who may be at higher risk.