Proliferating cell nuclear antigen in epithelial ovarian cancer: relation to results at second-look laparotomy and survival

Proteomic and Bioinformatic Studies for the Characterization of Response to Pemetrexed in Platinum Drug Resistant Ovarian Cancer

Proteomics and bioinformatics are a useful combined technology for the characterization of protein expression level and modulation associated with the response to a drug and with its mechanism of action. The folate pathway represents an important target in the anticancer drugs therapy. In the present study, a discovery proteomics approach was applied to tissue samples collected from ovarian cancer patients who relapsed after the first-line carboplatin-based chemotherapy and were treated with pemetrexed (PMX), a known folate pathway targeting drug. The aim of the work is to identify the proteomic profile that can be associated to the response to the PMX treatment in pre-treatement tissue. Statistical metrics of the experimental Mass Spectrometry (MS) data were combined with a knowledge-based approach that included bioinformatics and a literature review through ProteinQuest™ tool, to design a protein set of reference (PSR). The PSR provides feedback for the consistency of MS proteomic data because it includes known validated proteins. A panel of 24 proteins with levels that were significantly different in pre-treatment samples of patients who responded to the therapy vs. the non-responder ones, was identified. The differences of the identified proteins were explained for the patients with different outcomes and the known PMX targets were further validated. The protein panel herein identified is ready for further validation in retrospective clinical trials using a targeted proteomic approach. This study may have a general relevant impact on biomarker application for cancer patients therapy selection.

Utility of Proliferation Markers Ki-67 and Proliferating Cell Nuclear Antigen (PCNA) in the Evaluation of Uterine Papillary Serous Carcinomas

We examined proliferation markers Ki-67 and proliferating cell nuclear antigen (PCNA) to determine whether immunohistochemical staining results could predict outcome in 22 uterine papillary serous carcinomas (UPSC). Eighteen tumors (82%) had increased proliferation as demonstrated by Ki-67 immunostaining with 50% of these patients dying of disease. Twenty tumors (91%) showed high PCNA immunoreactivity; 60% of these patients died of disease. Most UPSC exhibit high immunoreactivity to Ki-67 and/or PCNA, which showed no correlation with outcome or stage. These results may reflect the aggressive clinical behavior of UPSC. We conclude that Ki-67 and PCNA immunohistochemistry have limited use as prognostic indicators in UPSC.

Lead article: The prognostic significance of proliferating cell nuclear antigen (pcna) in laryngeal cancer

Squamous cell carcinoma arising from upper aerodigestive tract carries with it a significant morbidity and mortality and, over the last few decades, its incidence has steadily increased. The management of patients requires thorough investigation to determine the local, regional, and distant extent of the disease, and treatment options include surgery, radiotherapy, chemotherapy, or combinations of these.Despite the large number of therapeutic and hsitopathologic studies in print, there is currently no morphologic or cytologic feature available which consistenly predicts outcome in patients with laryngeal carcinoma. The use of proliferating cell nuclear antigen (PCNA), a newly available marker of a cell's proliferative activity ( S-phase fraction), was evaluated in 25 cases of squamous cell carcinoma of the larynx. PCNA scores differed, statistically significantly as far as the localization of the lesion, pathological grade, clinical stage, presence of lymph node metastases and prognosis of the patients were concerned.These data suggest that PCNA is an indicator of the malignant potential of the larynx. PCNA can be used in decision making for treatment and assessing prognosis in carcinoma of the larynx.

Predictive and prognostic protein biomarkers in epithelial ovarian cancer: recommendation for future studies

Epithelial ovarian cancer is the most lethal gynecological malignancy. Due to its lack of symptoms, this disease is diagnosed at an advanced stage when the cancer has already spread to secondary sites. While initial rates of response to first treatment is >80%, the overall survival rate of patients is extremely low, mainly due to development of drug resistance. To date, there are no reliable clinical factors that can properly stratify patients for suitable chemotherapy strategies. Clinical parameters such as disease stage, tumor grade and residual disease, although helpful in the management of patients after their initial surgery to establish the first line of treatment, are not efficient enough. Accordingly, reliable markers that are independent and complementary to clinical parameters are needed for a better management of these patients. For several years, efforts to identify prognostic factors have focused on molecular markers, with a large number having been investigated. This review aims to present a summary of the recent advances in the identification of molecular biomarkers in ovarian cancer patient tissues, as well as an overview of the need and importance of molecular markers for personalized medicine in ovarian cancer.

Cellular Proliferation, Cell Death, and Liver Histology in Gambusia affinis After Dietary Exposure to Benzidine and 2-Aminofluorene

Chronic exposure to arylamines through diet and/or smoking has been associated with genetic changes and tumorigenesis. Cellular proliferation, apoptosis, and histological changes in liver tissue were investigated in Gambusia affinis ( G affinis) after chronic dietary exposure to 6.9 mM and 0.069 mM concentrations of benzidine (BZ), 2-aminofluorene (2AF), and their combination for 4, 8, and 12 weeks, respectively. The proliferation assay indicated non–dose-dependent increases in cellular proliferation over the controls for all treatment groups at 4 and 12 weeks but not at 8 weeks except for the low dose of 2AF. The apoptosis assay showed effects in the low-dose group of 2AF and BZ at 4 weeks only. Hematoxylin/eosin staining of liver tissue revealed an increase in oval/spindle cell proliferation and altered foci formation in the treated groups compared with controls. These results demonstrate a mammalian-like response to 2AF and BZ in G affinis liver.

Targeting slow-proliferating ovarian cancer cells

Advanced ovarian cancer has a high rate of recurrence and mortality despite relative chemosensitivity at the time of initial treatment. Conventional chemotherapeutic agents typically target rapidly dividing cells. Disease relapse may therefore result from the survival and later emergence of latent slow-proliferating and/or quiescent cancer cells. We sought to identify drugs that target this cell population and to investigate the influence of these cells on outcome of patients in remission from advanced ovarian cancer. Drugs with increased efficacy against slower proliferating cells were identified using correlation-based screening of 44,657 compounds tested on the NCI-60 panel of cancer cell lines. Validation of candidates was performed in comparison with Cisplatin or Paclitaxel and by manipulation of proliferation rates by serum deprivation. Cytostatic and cytocidal effects were evaluated using MTT assays and active caspase-3 immunocytochemistry. Ki-67 proliferation indices were determined for tumors from 104 patients in remission. UCN-01 efficacy was correlated with longer doubling time among the NCI-60 cell lines (R = 0.54, p < 0.0001) and in a panel of 24 ovarian cancer cell lines (R = 0.42, p = 0.04), whereas this was not the case for Cisplatin (R = -0.10, p = 0.65) and Paclitaxel efficacy correlated with shorter doubling time (R = -0.52, p = 0.009). Cytostatic and cytocidal effects of UCN-01 were increased in serum-deprived cells. A low proliferation index was associated with presence of persistent disease at second-look surgery (p = 0.01) and poor survival (disease-free survival, p = 0.002; overall survival, p = 0.04). These results suggest that targeting quiescent ovarian cancer cells may be a worthwhile therapeutic approach to improving survival of women with ovarian cancer.

Yin yang 1 modulates taxane response in epithelial ovarian cancer

Survival of ovarian cancer patients is largely dictated by their response to chemotherapy, which depends on underlying molecular features of the malignancy. We previously identified YIN YANG 1 (YY1) as a gene whose expression is positively correlated with ovarian cancer survival. Herein, we investigated the mechanistic basis of this association. Epigenetic and genetic characteristics of YY1 in serous epithelial ovarian cancer were analyzed along with YY1 mRNA and protein. Patterns of gene expression in primary serous epithelial ovarian cancer and in the NCI60 database were investigated using computational methods. YY1 function and modulation of chemotherapeutic response in vitro was studied using small interfering RNA knockdown. Microarray analysis showed strong positive correlation between expression of YY1 and genes with YY1 and transcription factor E2F binding motifs in ovarian cancer and in the NCI60 cancer cell lines. Clustering of microarray data for these genes revealed that high YY1/E2F3 activity positively correlates with survival of patients treated with the microtubule-stabilizing drug paclitaxel. Increased sensitivity to taxanes, but not to DNA cross-linking platinum agents, was also characteristic of NCI60 cancer cell lines with a high YY1/E2F signature. YY1 knockdown in ovarian cancer cell lines results in inhibition of anchorage-independent growth, motility, and proliferation but also increases resistance to taxanes, with no effect on cisplatin sensitivity. These results, together with the prior demonstration of augmentation of microtubule-related genes by E2F3, suggest that enhanced taxane sensitivity in tumors with high YY1/E2F activity may be mediated by modulation of putative target genes with microtubule function.

Alterations in the p53 pathway and prognosis in advanced ovarian cancer: a multi-factorial analysis of the EORTC Gynaecological Cancer group (study 55865)

PURPOSE

The study was designed to determine independent prognostic variables in suboptimally debulked advanced ovarian cancer patients entered in the randomised phase III study EORTC 55865.

EXPERIMENTAL DESIGN

Retrospectively collected paraffin blocks from 169 patients with stages IIb-IV epithelial ovarian cancer, taken at primary debulking surgery, were analysed. All patients were treated with cyclophosphamide and cisplatin (CP), and followed up for a median of 10 years. Expression of p53, bcl-2, P21, Ki-67 and HER-2 status was assessed by immunohistochemistry (IHC).

RESULTS

Expression of p21, a downstream effector of the p53 gene, was found to be a favourable prognostic factor for survival (HR 0.58, CI 0.36-0.94, p=0.025) in addition to FIGO stage (HR 1.54, CI 1.08-2.21, p=or<0.02). For progression free survival (PFS), both p21 (HR 0.52) and Ki-67 (HR 0.6) were significant factors.

CONCLUSION

P21 overexpression is a positive prognostic factor for survival and PFS in advanced ovarian carcinoma with residual lesions of more than 1 cm.

Prognostic significance of Ki-67 antigen immunostaining (MIB-1 monoclonal antibody) in ovarian cancer

OBJECTIVE

To assess the potential usefulness of Ki-67 antigen expression as a predictor of outcome in ovarian cancer through the analysis of MIB-1 monoclonal antibody reactivity.

METHODS

Cell proliferation and clinicopathologic variables were assessed in 26 patients with primary epithelial ovarian cancer who had undergone exploratory laparotomy. The expression of primary tumor proliferation related to Ki-67 antigen was immunohistochemically evaluated by MIB-1 monoclonal antibody.

RESULTS

The value of Ki-67 labeling index (LI) ranged between 0 and 92.6% with a mean of 48.9%. Ki-67 LI correlated well with the mitotic index, but not the histological subtype. Ki-67 LI of more than 40%was defined as a higher proliferating tumor by a receiver operating characteristic curve analysis. Higher proliferating tumors were identified in 14 patients (54% of all subjects). The patients with higher proliferating tumors had a statistically significantly worse prognosis compared with those with lower proliferating tumors (p<0.001).

CONCLUSIONS

The present study demonstrates that the proliferating index detected by Ki-67 antigen immunostaining is a useful factor for predicting the survival of patients with ovarian cancer.

Cell kinetics and apoptosis in laryngeal carcinoma patients

Cellular proliferation and apoptosis are both implicated in the process of carcinogenesis. The objective of this study was to access the prognostic significance of the expression of proliferating cell nuclear antigen (PCNA) and the apoptosis-related genes (bax, bcl-2, and p53) in laryngeal carcinoma patients. Thirty consecutive patients with stage I to IV squamous cell laryngeal carcinoma were treated in our department from 1992 to 1994. We immunohistochemically studied the expression of PCNA and bax, bcl-2, and p53 genes in their tumor specimens. Five healthy men were used as the control group. The staining results were correlated with clinicopathologic data. The PCNA protein expression was correlated with a significantly worse survival in those patients who were bax-negative (0% versus 42.86%, p = .0445). Similarly, the presence of PCNA led to an unfavorable clinical outcome in those patients who were bax-negative, bcl-2-negative, and p53-negative (0% versus 50%, p = .0278). Expression of bcl-2 protein was found to be an independent prognostic factor related to an unfavorable clinical outcome (p = .0262). The expression of bcl-2 protein appears to predict survival in laryngeal carcinoma patients. Furthermore, the combined study of proliferation markers and apoptosis-related genes helped us to identify a high-risk group of patients who may benefit from a more aggressive treatment protocol.

Molecular aspects of ovarian cancer

Ovarian cancer is caused by genetic alterations that disrupt proliferation, apoptosis, senescence and DNA repair. Approximately 10% of ovarian cancers arise in women who have inherited mutations in cancer susceptibility genes (BRCA1 or BRCA2). The ability to perform genetic testing allows identification of women at increased risk who can be offered prophylactic oophorectomy or other interventions aimed at preventing ovarian cancer. The vast majority of ovarian cancers are sporadic, resulting from the accumulation of genetic damage over a lifetime. Several specific genes involved in ovarian carcinogenesis have been identified, including the p53 tumour suppressor gene and HER2/ neu andPIC3KA oncogenes. The recent availability of expression microarrays has facilitated the simultaneous examination of thousands of genes, and this promises to extend further our understanding of the molecular events involved in the development of ovarian cancers. Hopefully, this knowledge can be translated into effective screening, treatment, surveillance, and prevention strategies in the future.

Expression of cell cycle proteins in ovarian carcinoma cells in serous effusions-biological and prognostic implications

OBJECTIVE

The aim of this study was to investigate the expression of cell cycle proteins in ovarian carcinoma cells in serous effusions and respective solid tumors.

METHODS

Fifty-five malignant effusions and 38 tumors (20 primary, 18 metastatic) were immunohistochemically stained for cyclin A, p27(kip1), and Ki-67. Staining extent (0-100% cells) and intensity (0-3 scale) were scored. Cyclin A and p27(kip1) expression was additionally studied in 29 malignant effusions using immunoblotting. Immunohistochemistry results in effusions were evaluated for possible association with clinicopathologic parameters.

RESULTS

Nuclear immunoreactivity for all markers was detected on carcinoma cells in the majority of effusions using immunohistochemistry. Similarly, immunoblotting showed the presence of cyclin A and p27(kip1) in 29/29 and 25/29 specimens, respectively. Intense (3) immunoreactivity for Ki-67 was detected more often in peritoneal effusions, compared with those of pleural location (P = 0.036). Staining in primary and metastatic lesions was generally comparable to that of tumor cells in effusions. Staining for p27(kip1) was more diffuse in effusion specimens obtained prior to the institution of chemotherapy (P = 0.042). In an analysis of all effusions, an association was observed between the number of cells that were immunoreactive for Ki-67, cyclin A, and p27(kip1) (cyclin A-Ki-67: P = 0.008; p27(kip1)-Ki-67: P = 0.019; cyclin A-p27(kip1): P = 0.032). In survival analysis, the presence of more diffuse (P = 0.042) and intense (P = 0.019) staining for cyclin A correlated with prolonged overall survival.

CONCLUSIONS

The expression of the studied cell cycle markers does not differ markedly between ovarian carcinoma cells in the pleural and peritoneal cavity, supporting our previous studies of several metastasis-associated molecules. The presence of cyclin-A-positive cell populations is associated with a more favorable disease outcome, possibly due to the targeting of proliferating cells by chemotherapeutic agents. However, the decline in the fraction of p27(kip1)-positive cells in posttreatment specimens may point to additional mechanisms involved in this selection.

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.

[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.

Immunogold labelling of PCNA and Ki-67 antigen at the ultrastructural level in laryngeal squamous cell carcinoma and its correlation with lymph node metastasis and histological grade

Streptavidin-gold was used for the immunolocalization of PCNA and Ki-67 antigen at the ultrastructural level with a postembedding technique in biopsies of 15 patients with laryngeal squamous cell carcinoma. Positive immunoelectron staining was obtained in 9 cases for PCNA (60%) and in 8 cases for Ki-67 (53%). PCNA was predominantly found in heterochromatin of the nucleus of laryngeal carcinoma cells in a granular pattern. Positivity for PCNA was not found in nucleoli. In 4 cases, positive staining was observed both in nucleus and cytoplasm. In the cytoplasm, it was found to be present on the endoplasmic reticulum and on ribosomes throughout the cytoplasm. Ki-67 antigen was localized in the nucleus where it was associated with heterochromatin and euchromatin. It was also observed in nucleoli in all cases. Cytoplasmic localization of Ki-67 antigen was similar to that of PCNA. All 8 cases that were positive for Ki-67 were also positive for PCNA. Control incubations did not result in labelling with steptavidin-gold particles for both antigens. A significant correlation between PCNA and Ki-67 expression in association with pathological characteristics such as nodal status and histological grade was not found. Our data indicate that Ki-67 antigen staining correlates with PCNA labelling, whereas a relationship between proliferation markers and tumour progression was not found.

Molecular and cytokinetic pretreatment risk assessment in endometrial carcinoma

OBJECTIVE

Our objective was to determine whether cytokinetic and molecular analyses of curettage specimens can provide a mechanism for triage of patients with endometrial cancer before initiating definitive surgical treatment.

METHODS

Pretreatment analysis consisted of flow cytometric determination of ploidy, S-phase fraction (SPF), and proliferative index (PI) and immunohistochemical determination of expression of proliferating cell nuclear antigen, HER-2/neu, and p53 in curettage specimens from 134 patients with endometrial carcinoma who subsequently had surgical staging and definitive surgical treatment. Fisher's exact test or chi(2) was used to examine the association between pretreatment variables and traditional surgical-pathologic indices. The log-rank test was used for univariate survival analysis. Cox proportional hazards identified the most important molecular factors.

RESULTS

Nondiploid status, SPF >/=9%, and PI >/=14% were associated with the traditional posttreatment prognostic indices, stage, grade, and histologic subtype. Univariate survival analysis demonstrated a correlation between nondiploid status, SPF >/=9%, PI >/=14%, and p53 overexpression and decreased progression-free survival (PFS) and disease-related survival (DRS). Stepwise Cox regression analysis identified p53 overexpression and SPF >/=9% as the most significant pretreatment molecular risk factors. A model stratifying patients according to whether none, one, or both of these two pretreatment factors were present showed that when both factors are present the risk for recurrence was higher (RR = 7.07; 95% confidence interval [CI], 3.06-16.38; P < 0.01) and death due to disease was higher (RR = 9.93; 95% CI, 3.92-25.19; P < 0.01) than when no factors are present. In the group with both factors, 5-year PFS and DRS estimates were 41 and 44%, respectively, compared with 86 and 86% and 90 and 92% for the "none" and "one" groups, respectively.

CONCLUSION

When observed simultaneously, increased SPF and p53 overexpression defined a group of patients at high risk for rapid recurrence and death due to disease. Pretreatment molecular analysis of curettage specimens could provide a mechanism of triage that could be applied before definitive surgical treatment.

Tumour cell kinetics as predictors of response in canine lymphoma treated with chemotherapy alone or combined with whole body hyperthermia

Kinetic parameters including potential doubling time (Tpot), duration of S phase (Ts), labelling index (LI), and DNA index (DI) were obtained from 42 dogs with previously untreated lymphoma. Standard flow cytometric techniques using BrdUrd were employed. All dogs were treated with L-asparaginase and remission was induced in 26 dogs, which were then randomized to receive chemotherapy only (doxorubicin [DOX] alone or with lonidamine) or chemotherapy plus whole body hyperthermia (WBH). Dogs were treated every 3 weeks for up to five treatments and evaluated every 3 weeks for evidence of tumour recurrence. Within this subset of animals there was no difference in outcome based on treatment group. Median values for Tpot, Ts and LI were 3.4 days, 7.23 h and 12.49%, respectively. Dogs that had tumours with LI > or = 20% had a shorter time until recurrence than dogs with tumours characterized by LI < 20%. In dogs treated only with chemotherapy, dogs bearing tumours with longer than median Tpot and Ts values and lower than median LI had significantly longer remission duration than dogs with more rapidly proliferating tumours. Dogs treated only with chemotherapy, which had longer than median Tpot and Ts values and lower than median LI, had significantly longer remission duration than all other dogs in the study. The mechanisms in which kinetics are associated with response to chemotherapy are not clear and vary depending on tumour type and treatment regimen. More work is needed to understand factors involved in cell killing during in vivo hyperthermia.

Influence of chemotherapy on the expression of p53, HER-2/neu and proliferation markers in ovarian cancer

OBJECTIVE

Mutated p53 and HER-2/neu play a role in the etiology of ovarian cancer. It is important to know whether the expression of these proteins is affected by platinum-containing chemotherapy.

STUDY DESIGN

Together with the cell proliferation markers Ki-67 and PCNA, the expression of p53 and HER-2/neu was assessed before and after chemotherapy. Paraffin-embedded tumor sections from 20 patients with ovarian cancer and four patients with benign disorders of the ovaries (controls) were analyzed. The expression of p53 was determined by the antibodies DO-1 and BP53-12. In addition to HER-2/neu and PCNA specific antibodies, MIB-1 was used to detect Ki-67.

RESULTS

The expression of all markers was higher in ovarian cancer patients than in non-malignant controls. MIB-1 showed a significant increase of expression after chemotherapy (P=0.002). HER-2/neu, p53 and PCNA also showed a clear increase after treatment, but this was not statistically significant. HER-2/neu is of prognostic relevance with respect to the response to chemotherapy (P=0.005) and survival (P=0.0002).

CONCLUSION

The different markers tested all increase after chemotherapy, but the differences are not statistically significant. Low HER-2/neu expression correlates with good outcome at second look.

p53, c-erbB2, and PCNA status in benign, proliferative and malignant ovarian surface epithelial neoplasms: a study of 75 cases

Low malignant potential tumors of the ovary are believed to behave in a manner intermediate to their benign and malignant counterparts. However, recent evidence suggests these lesions are in fact benign and better classified as proliferative. Based on our previous work and evaluating p53, c-erbB2, and PCNA status in a full spectrum of ovarian surface epithelial tumors, with emphasis on low malignant potential tumors, we tested this hypothesis. Immunohistochemical stains with monoclonal antibodies were used on 75 archival ovarian neoplasms. The results demonstrated anti-p53 reactivity in 30 carcinomas (40%), 2 of which were proliferative, and no reactivity in the benign tumors. Overexpression of c-erbB2 was seen in 31 malignant neoplasms (64.5%), 4 of which were proliferative (22.1%), and none in benign tumors. The PCNA proliferative index showed means of 42.8%, 22.8%, and 14.9% with benign, low malignant potential, and malignant tumors, respectively. Predicting immunoreactivity in carcinomas for anti-PCNA (Student t test), anti-p53, and anti-c-erbB2 (Pearson chi2 test) versus a lack of immunoreactivity in proliferative tumors indicate P values of .001, <.001, and <.001, respectively. These data show significant differences in the expression of these markers in ovarian tumors and suggest a possible role for these oncogenes as supplemental tools in diagnostic pathology. Further, our findings also support the designation of proliferative as opposed to the current nomenclature of low malignant potential tumors.

Tumor response to neoadjuvant chemotherapy correlates with the expression of P-glycoprotein and PCNA but not GST-pi in the tumor cells of cervical carcinoma

OBJECTIVE

To identify the clinicopathological and chemoresistant factors predicting the response to neoadjuvant chemotherapy and the patient prognosis in high-risk cervical carcinomas.

METHODS

We retrospectively reviewed 47 patients with locally advanced or bulky cervical carcinoma treated with two courses of intraarterial infusion of cisplatin, doxorubicin, mitomycin C, and 5-fluorouracil (5-FU), followed by radical hysterectomy at our hospital between 1988 and 1995. Expressions of the chemoresistance-related proteins, such as P-glycoprotein, glutathione S-transferase pi (GST-pi), and proliferating cell nuclear antigen (PCNA) in the tumor cells, were examined by immunohistochemistry using pretreatment biopsy specimens. These results were compared with the chemotherapeutic response, which was evaluated by magnetic resonance imaging (MRI) and histopathology. Outcome of the patients was also studied.

RESULTS

Chemotherapeutic effect of either complete (CR) or partial (PR) response on MRI was obtained in 36 of the 47 (86%) patients. Poor response to chemotherapy was significantly correlated with P-glycoprotein expression (P < 0.005) and low PCNA labeling (P < 0. 05), but not GST-pi expression in the tumor cells. Independent prognostic factors for patient survival were parametrial involvement and lymph node metastasis. Neither the expression of GST-pi nor PCNA was correlated with the patient survival.

CONCLUSION

Assessment of the expression of P-glycoprotein and PCNA is potentially useful for the prediction of tumor response to neoadjuvant chemotherapy for cervical carcinomas.

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.

Modulation of expression of p53 and cell proliferation in locally advanced cervical carcinoma after neoadjuvant combination chemotherapy

OBJECTIVE

In the present study, we investigated changes of p53 expression and the cell proliferation index detected with MIB 1 in tumors before and after neoadjuvant combination chemotherapy with respect to the outcome of the disease. Our aim was to define more appropriately the significance of chemotherapy in locally advanced cervical carcinoma.

MATERIALS AND METHODS

Our study included 17 women with locally advanced squamous cervical carcinoma who had been admitted to the Institute of Gynecology and Obstetrics Ancona University, between January 1990 and December 1994. The patients received neoadjuvant combination chemotherapy consisting of three cycles of cisplatin (80 mg/m2) and bleomycin (30 mg/m2). After chemotherapy, radical surgery was performed. Bioptic specimens were obtained from cervical tumors before and after chemotherapy and processed for immunohistochemical staining with a monoclonal antibody against p53 and with the monoclonal antibody MIB 1.

RESULTS

Thirteen patients (76.5%) showed a clinical response (4 complete and 9 partial), while of the remaining 4 cases (23.5%) 3 had no change and 1 showed progression after neoadjuvant combination chemotherapy. A significant relationship was observed between the overexpression of p53 and the sensitivity to chemotherapy; responder patients showed a higher frequency of p53 positive cells than non-responders (P = 0.03). No significant relationship with MIB 1 index was observed. Both expression of p53 protein (P < 0.001) and reaction with MIB 1 (P = 0.003) significantly decreased after chemotherapy. The decrease in expression of p53 protein and staining with antibody MIB 1 was particularly evident in patients who responded to chemotherapy.

DISCUSSION

In tumors, p53 protein and index of proliferating cells as determined with MIB 1 showed a significant modulation after treatment, suggesting an association with sensitivity to chemotherapy. However, the limited number of our series of patients does not permit a statement on the clinical implication of expression of p53 and cell proliferation in patients undergoing neoadjuvant combination chemotherapy for locally advanced cervical carcinoma.

Comparative flow cytometric analysis of Ki-67 and proliferating cell nuclear antigen (PCNA) in solid neoplasms

The proliferation associated antigens, Ki-67 and proliferating-cell nuclear antigen (PCNA), have been widely used in studies assessing the growth fraction in human malignancies. It remains unclear, however, whether these markers yield similar assessments of proliferative activity in any given neoplasm. In this study, we compared Ki-67 and PCNA expression in 93 malignant solid neoplasms using bivariate flow cytometric analysis of these antigens and DNA content. The growth fractions measured by Ki-67 and PCNA were compared and correlated with acridine orange (AO) analysis and tumor grade. Our results indicate a significant difference between Ki-67 and PCNA values in neoplasms of low and intermediate grade (P = 0.002); Ki-67 values were significantly lower than those obtained by PCNA in this group. No statistical difference between Ki-67 and PCNA values was found in high grade neoplasms (P = 0.38). Analysis of different cell cycle compartments indicates that the observed difference in the positivity of these markers was due to their differential expression in the G0/1 segment of the cell cycle. We conclude that Ki-67 may better reflect the proliferative activity in solid neoplasms than does PCNA.

High correlation with survival of proliferating cell nuclear antigen expression in mucoepidermoid carcinoma of the parotid gland

We tested the hypothesis that proliferating cell nuclear antigen can predict survival in patients with mucoepidermoid carcinoma. Formalin-fixed, paraffin-embedded, tissue resected specimens from 43 patients with no prior treatment for mucoepidermoid carcinoma of the parotid gland were immunostained with the PC10 monoclonal antibody to proliferating cell nuclear antigen with the peroxidase/antiperoxidase method. Proliferating cell nuclear antigen levels were defined as the number of nuclei with strong immunostaining divided by the total cell count and were expressed as percentages. Both univariate and multivariate analyses were performed on 12 additional prognostic variables to determine the relative proliferating cell nuclear antigen level to predict survival. The median proliferating cell nuclear antigen level was 7. Five percent of patients with proliferating cell nuclear antigen levels less than 7 died of their disease compared with 48% of those with proliferating cell nuclear antigen levels of 7 or more. Multivariate analysis indicates proliferating cell nuclear antigen to be the most important parameter in predicting survival. Thus the measurement of proliferating cell nuclear antigen is a useful predictor of survival for patients with mucoepidermoid carcinoma of the parotid gland.

Comparative flow cytometric analysis of proliferating cell nuclear antigen (PCNA) antibodies in human solid neoplasms

Proliferating cell nuclear antigen (PCNA), an auxiliary protein of DNA polymerase delta, associated with DNA synthesis, is increasingly used to determine tumor growth rate. To determine the growth fraction by PCNA, various antibodies and fixation procedures are being used. We assessed the flow-cytometric measurement of PCNA using three monoclonal antibodies (PC10, 19F4, and 19A2) and two fixation protocols (paraformaldehyde and methanol) in tissue-culture cell lines and human solid neoplasms to determine their potential clinical application. Thirty-one solid tumors and four normal tissues were analyzed, along with MOLT-4 and HL-60 cell lines as positive controls and normal peripheral blood lymphocytes as a negative control. PC10 with methanol fixation consistently detected higher PCNA positivity in human solid neoplasms than 19F4 and 19A2. Using PC10, the differences in positivity among fixation methods occurred in the G0/1 phase, not in S + G2M, of the cell cycle. No correlation was found between PCNA positivity and tumor grade and DNA ploidy in tumors analyzed. A statistical correlation was found between overall PCNA positivity and RNA content as determined by acridine orange analysis. The growth fraction by PCNA in solid neoplasms was most reliably determined by PC10 with methanol fixation.