Proliferation in the normal cervix and in preinvasive cervical lesions

Association of TGFβ signaling with the maintenance of a quiescent stem cell niche in human oral mucosa

A dogma in squamous epithelial biology is that proliferation occurs in the basal cell layer. Notable exceptions are squamous epithelia of the human oral cavity, esophagus, ectocervix, and vagina. In these human epithelia, proliferation is rare in the basal cell layer, and the vast majority of cells positive for Ki67 and other proliferation markers are found in para- and suprabasal cell layers. This unique human feature of a generally quiescent basal cell layer overlaid by highly proliferative cells offers the rare opportunity to study the molecular features of undifferentiated, quiescent, putative stem cells in their natural context. Here, we show that the quiescent human oral mucosa basal cell layer expresses putative markers of stemness, while para- and suprabasal cells are characterized by cell cycle genes. We identified a TGFβ signature in this quiescent basal cell layer. In in vitro organotypic cultures, human keratinocytes could be induced to express markers of these quiescent basal cells when TGFβ signaling is activated. The study suggests that the separation of basal cell layer and proliferation in human oral mucosa may function to accommodate high proliferation rates and the protection of a quiescent reserve stem cell pool. Psoriasis, an epidermal inflammatory hyperproliferative disease, exhibits features of a quiescent basal cell layer mimicking normal oral mucosa. Our data indicate that structural changes in the organization of epithelial proliferation could contribute to longevity and carcinogenesis.

Oncogenic human papillomaviruses activate the tumor-associated lens epithelial-derived growth factor (LEDGF) gene

The expression of the human papillomavirus (HPV) E6/E7 oncogenes is crucial for HPV-induced malignant cell transformation. The identification of cellular targets attacked by the HPV oncogenes is critical for our understanding of the molecular mechanisms of HPV-associated carcinogenesis and may open novel therapeutic opportunities. Here, we identify the Lens Epithelial-Derived Growth Factor (LEDGF) gene as a novel cellular target gene for the HPV oncogenes. Elevated LEDGF expression has been recently linked to human carcinogenesis and can protect tumor cells towards different forms of cellular stress. We show that intracellular LEDGF mRNA and protein levels in HPV-positive cancer cells are critically dependent on the maintenance of viral oncogene expression. Ectopic E6/E7 expression stimulates LEDGF transcription in primary keratinocytes, at least in part via activation of the LEDGF promoter. Repression of endogenous LEDGF expression by RNA interference results in an increased sensitivity of HPV-positive cancer cells towards genotoxic agents. Immunohistochemical analyses of cervical tissue specimens reveal a highly significant increase of LEDGF protein levels in HPV-positive lesions compared to histologically normal cervical epithelium. Taken together, these results indicate that the E6/E7-dependent maintenance of intracellular LEDGF expression is critical for protecting HPV-positive cancer cells against various forms of cellular stress, including DNA damage. This could support tumor cell survival and contribute to the therapeutic resistance of cervical cancers towards genotoxic treatment strategies in the clinic.

Specific types of human papillomaviruses (HPVs) are closely linked to the development of malignant tumors, such as cervical cancer. Virtually all cervical cancers contain HPV DNA and the tumorigenic growth behavior of cervical cancer cells is dependent on the activity of two viral oncogenes, called E6 and E7. It is important to study the activities by which the HPV oncogenes can support the growth of tumor cells. This should allow new insights into the molecular mechanisms of virus-induced carcinogenesis and could also be useful for developing novel approaches for cancer therapy. We here show that the HPV oncogenes stimulate and maintain expression of the cellular LEDGF gene in HPV-positive cancer cells. Consistently, pre-malignant and malignant lesions of the cervix exhibit significantly increased LEDGF protein levels. LEDGF is crucial for the protection of tumor cells against various forms of cellular stress, including DNA damage. LEDGF stimulation by the viral oncogenes could be a critical survival mechanism by which HPVs support the growth of cervical cancer cells and provide resistance towards chemo- and radiotherapy in the clinic.

Nucleoporin 88 expression in normal and neoplastic squamous epithelia of the uterine cervix

This study investigated the expression of nucleoporin 88 (Nup88) in formalin-fixed, paraffin-embedded archival tissues of cervical specimens consisting of normal ectocervical squamous epithelia (n = 34), low-grade squamous intraepithelial lesions corresponding to cervical intraepithelial neoplasia (CIN) 1 (n = 9), high-grade squamous intraepithelial lesions corresponding to CIN2 and CIN3 (n = 28), and invasive squamous cell carcinoma (ISCC; n = 30) to determine whether expression of this factor is involved in the progression of the morphological spectrum from normal cervical epithelia to CIN and cervical ISCC. A standard immunohistochemical technique was performed using a Ventana BenchMark XT immunostainer with a mouse antihuman monoclonal antibody to Nup88. Immunostaining was scored with regard to quantity and intensity of positively stained cells, with final immunoscores from 0 to 12 in each case. Nucleoporin 88 immunoscores increased significantly from normal ectocervical squamous epithelia to CIN1, CIN2/3, and ISCC (P < .0001, analysis of variance). Cervical intraepithelial neoplasia 2/3 as isolated lesions and adjacent to ISCC did not differ significantly. A significant correlation was noticed for immunoscores of CIN2/3 adjacent to ISCC and the corresponding ISCC (P = .0007). This study indicates that Nup88 is significantly overexpressed in high-grade CIN lesions and ISCC compared with normal ectocervical squamous epithelia and CIN1. However, Nup88 evaluation is of limited value as a diagnostic marker in individual cases.

Activation of the enhancer of zeste homologue 2 gene by the human papillomavirus E7 oncoprotein

The malignant phenotype of human papillomavirus (HPV)-positive cancer cells is maintained by the activity of the viral E6 and E7 genes. Here, we identified the polycomb group gene enhancer of zeste homologue 2 (EZH2) as a novel downstream target for the viral oncogenes in HPV-transformed cells. EZH2 expression was activated by HPV16 E7 at the transcriptional level via E7-mediated release of E2F from pocket proteins. RNA interference analyses showed that continuous EZH2 expression is required for the proliferation of HPV-positive tumor cells by stimulating cell cycle progression at the G1-S boundary. In addition to its growth-promoting activity, EZH2 also contributed to the apoptotic resistance of cervical cancer cells. Furthermore, we found that HPV-positive dysplastic and tumorigenic cervical lesions were characterized by high levels of EZH2 protein in vivo. We conclude that the E7 target gene EZH2 is a major determinant for the proliferation of HPV-positive cancer cells and contributes to their apoptotic resistance. Moreover, EZH2 may serve as a novel therapeutic target for the treatment of cervical cancer.

Thickness of the cervical epithelium of autopsied patients with acquired immunodeficiency syndrome

Several general pathologic processes that affect the uterine cervix have been described in Brazil and in the world. The aim of the current study was to evaluate morphometrically the cervical epithelium of autopsied patients with AIDS. This is a cross-sectional study of the cervix of 38 women autopsied from 1993 to 2003. We evaluated the cervix of women aged 20 to 40 years, 20 with AIDS (52.63%) and 18 without (47.37%). The inflammatory infiltrate found in the AIDS patients was more accentuated and predominantly composed of monocytes, which is characteristic of chronic inflammation. In addition, necrosis, fibrosis, and metaplasia were also more frequent in these patients. The cervical epithelium was considerably thinner in the AIDS patients. This hypotrophy occurred because of a significantly accentuated reduction in the number and surface area of cells (P < .01). There was still a significant correlation between the thickness of the epithelium and the nutritional status of AIDS patients. General pathologic processes, which affect the cervices of patients with AIDS, especially hypotrophy, could facilitate the penetration of other infectious agents. We suggest that the nutritional status of these patients and the adherence to antiretroviral therapy be routinely evaluated and the use of condoms stimulated even between HIV-positive partners to prevent possible increases in the viral load and reinfections that contribute to the aggravation of the disease.

Extracellular signal-regulated protein kinase is activated in cervical intraepithelial neoplasms but inactivated in invasive cervical carcinoma

The extracellular signal-regulated protein kinase (ERK) signaling pathway has been reported to play important roles in cell growth in various neoplasms. The purpose of the present study was to immunohistochemically analyze the phosphorylation status (activity) of ERK in 24 cases of cervical carcinoma using an antiphosphorylated ERK antibody (alphap-ERK Ab) that specifically recognizes the phosphorylated form of ERK (p-ERK). In normal cervical epithelium, p-ERK was found to be confined to basal cells that were negative for Ki-67, suggesting that ERK was not activated in proliferating normal cervical epithelium. In cervical intraepithelial neoplasms (CIN), increased abnormal parabasal cells were positive for both p-ERK and Ki-67, suggesting that ERK activation in CIN may be involved in tumor cell proliferation. In contrast, it was found that, in invasive cervical carcinomas, almost all the carcinoma cells were positive for Ki-67 but negative for p-ERK, suggesting that, in contrast to many other types of cancers, the ERK signaling pathway is downregulated in invasive cervical carcinoma. These findings suggest that the phosphorylation status of ERK differs between CIN and invasive carcinomas, and that downregulation of the ERK signaling pathway may contribute to transformation of CIN to invasive cervical carcinomas.

Altered expression of cellular membrane molecules of HLA-DR, HLA-G and CD99 in cervical intraepithelial neoplasias and invasive squamous cell carcinoma

OBJECTIVE

The aim of this study was to investigate the role of HLA-DR, HLA-G and CD99 during cervical carcinogenesis and to examine the prognostic significance of these protein expressions in invasive squamous cell carcinoma (SCC).

METHODS

Using specific antibodies for HLA-DR, HLA-G and CD99, we examined protein expressions in 19 normal cervix, 15 mild dysplasia (CIN I), 22 moderate dysplasia (CIN II), 23 severe dysplasia (CIN III), and 34 invasive squamous cell carcinoma by immunohistochemistry. And we detected the expression of Ki67 in the same specimens.

RESULTS

None of normal cervix and CINs except three cases of CIN III expressed HLA-DR. HLA-DR expression increased progressively with the grade of the tumor, and significant differences could be observed between grade 1 and grade 2 (P<0.01) and between grade 1 and grade 3 (P<0.05). In all normal epithelial control samples, HLA-G expression was seen in ectocervical squamous and endocervical columnar epithelium and the staining was strong and uniform. Only a small proportion of CINs and SCCs showed reduced expression of HLA-G. Compared with the results in the control samples, CINs and SCCs showed significantly reduced expression of HLA-G (P<0.001). SCCs showed significantly increased expression of CD99 when compared with normal cervix and CINs (P<0.05). Ki67 was expressed in all specimens. Significant differences were observed between CINs and normal cervix (P<0.001) and SCCs and controls (P<0.001), but no significant differences could be observed between SCCs and CINs. None of the expressions of these proteins was associated with any of clinicopathological parameters.

CONCLUSIONS

These results indicate that increased expression of HLA-DR and CD99 may be related to the evolution of cervical cancer. All protein expressions were not associated with clinicopathological parameters.

The Ki-67 Labeling Index Is Not a Useful Predictor for the Follow-up of Cervical Intraepithelial Neoplasia 1

OBJECTIVE

Our aim was to determine whether the Ki-67 immunostaining pattern, present on diagnosis of cervical intraepithelial neoplasia (CIN), predicts the change from low-grade to high-grade CIN over a 2-year period after diagnosis.

MATERIALS AND METHODS

Of 59 cervical biopsy samples from 59 patients diagnosed as having cervical CIN, 35 were diagnosed as CIN 1 and 24 were diagnosed as CIN 2 or CIN 3. The Ki-67 immunostain showed immunopositive cells in the upper two thirds of the epithelium in all specimens. Two hundred nuclei were counted in 25 high-power fields in each specimen, including all of the epithelial layers, to determine the mean number of Ki-67-positive cells. In situ hybridization was used to demonstrate and type human papillomavirus. The chi test, Fisher exact test, Student t test, one-way analysis of variance, and Tukey test were used for statistical analysis, with significance set at p < .05.

RESULTS

The mean Ki-67 labeling index for CIN 1, CIN 2, CIN 3, and CIN 2,3 were, respectively, 32.5%, 43.2%, 53.2%, and 47.8%. The statistical study showed significant differences between CIN 1 versus CIN 2, CIN 1 versus CIN 3, and CIN 1 versus CIN 2,3. For CIN 1, the mean Ki-67 labeling index was 32.8% when the lesion disappeared and was 34.6% for persisting lesions. There was no statistically significant difference.

CONCLUSIONS

Ki-67 labeling index did not predict persisting CIN 1.

A three-dimensional organotypic culture of the human uterine exocervix for studying mucosal epithelial differentiation and migrating leukocytes

We report on a three-dimensional organotypic culture in vitro of explants from the human uterine exocervix. Exocervical fragments (2-3 mm3) from pre-menopausal women were cultured on sponges submerged in Dulbecco's Modified Eagle's Medium containing p-nonylphenol and 10% fetal bovine serum for up to 3 weeks and the viability and cellular responses were assayed. The fragments were analyzed by immunohistochemistry for the expression and distribution of a broad spectrum of cellular markers: p63, Ki-67, involucrin, high molecular weight cytokeratins, estrogen receptor-alpha, vimentin, CD45, and CD31. The fragments preserved their tissue architecture and cellular heterogeneity comparable to that observed in exocervical tissue in vivo. Prior to culture, the original epithelium was composed of stratified multilayered keratinocytes with integrated monocyte/dendritic-like cells in the basal and suprabasal layers. The epithelium began to exfoliate in culture and within 4 days appeared to have lost its differentiated high-zone layers of keratinocytes. After 10 days a new epithelium, slightly different from the original one, was formed; it displayed an increasing prominence of basal and suprabasal keratinocyte layers, containing infiltrating leukocytes that had probably migrated from the submucosa. The epithelium subsequently lost its organization, concomitant with a progressive involution of the stroma. Subepithelial capillaries appeared to be well maintained throughout the culture period. Aside from the maintenance of cellular heterogeneity within the fragments of exocervix, these culture systems are a valuable tool for studying the mechanisms of epithelial regeneration, and may prove to be a useful model for studying mucosal immunity.

Endometriosis-associated ovarian carcinoma: differential expression of vascular endothelial growth factor and estrogen/progesterone receptors

BACKGROUND

Multiple epidemiologic and histologic studies have suggested that ovarian endometriosis can give rise to malignant ovarian tumors, primarily those of epithelial origin. The progression of endometriosis to endometriosis-associated ovarian carcinoma (EAOC) has not been investigated thoroughly and is poorly understood at best. Using immunohistochemical methods, we compared the differential expression patterns of various cytokines and growth factors in atypical endometriosis (AE) and EAOC.

METHODS

Using the Johns Hopkins Pathology Data Bank, tissue blocks from patients diagnosed with EAOC or AE were identified. Tissue blocks were stained for 4 markers: vascular endothelial growth factor (VEGF), Ki-67, estrogen receptor (ER), and progesterone receptor (PR).

RESULTS

Seventeen cases of EAOC and 8 cases of AE were identified. Staining for VEGF was documented in 16 of 17 (94%) EAOC tissue blocks and in only 1 of 8 (12.5%) AE tissue blocks (P < 0.0001). Only 4 of the 17 (23%) EAOC tissue blocks exhibited positive staining for ER, compared with 8 of 8 (100%) AE tissue blocks (P = 0.0005). Positive staining for PR was noted in only 6 of 17 (35%) EAOC samples but was present in 8 of 8 (100%) AE samples (P = 0.003). Seventy percent of EAOC samples exhibited positive staining for Ki-67, compared with 37.5% of AE samples (P = 0.19).

CONCLUSIONS

EAOC appears to be associated with overexpression of VEGF and reduced expression of both ER and PR. Variations in VEGF expression may be associated with the malignant transformation of endometriosis and may present both diagnostic and therapeutic options for the treatment of ovarian malignancies.

Changes in the topological expression of markers of differentiation and apoptosis in defined stages of human cervical dysplasia and carcinoma

OBJECTIVE

We compared the capacity of cells in normal cervical epithelium, progressive stages of CIN, and invasive carcinoma to proliferate, differentiate, and undergo apoptosis.

METHODS

We investigated 30 conizations showing regular squamous epithelium of the ectocervix, all stages of cervical preinvasive neoplastic lesions (CIN I to III), or invasive carcinoma. The expression of the cell proliferation and differentiation marker Ki67 and Mad-1, respectively, and of the apoptosis-related proteins bcl-2, active caspase-3, and DNase I was analyzed on paraffin sections by immunohistochemistry. The expression of DNase I or -like enzymes was also analyzed at the level of their gene transcripts by in situ hybridization. In addition, apoptotic events were identified by in situ end labeling of fragmented DNA (ISEL).

RESULTS

Expression of Ki67 was restricted to suprabasal cells in normal cervical epithelium but increased with CIN severity and invasive carcinoma. ISEL demonstrated apoptosis in superficial layers of normal, CIN I, and CIN II epithelium, whereas in CIS (CIN III) and invasive carcinoma, ISEL-positive cells were additionally observed at varying epithelial locations. Bcl-2 immunostaining remained restricted to the basal layer of all preneoplastic and neoplastic stages. Active caspase-3 was present in the suprabasal layer and extended to all upper layers in normal epithelium and slightly decreased with increasing dysplasia. In invasive carcinoma it was restricted to few scattered cells. The differentiation marker Mad-1 extended from the spinous to the superficial layer in regular epithelium, but gradually shifted to more superficial layers with increasing CIN grade and invasive carcinoma. A similar topological change was observed for DNase I with increasing CIN grade. In CIS and invasive carcinoma, DNase I immunopositive cells were solely interspersed within neoplastic cells. In contrast, DNase I specific mRNA was present in all epithelial layers in CIN III and neoplasia, suggesting a translational block of the expression of DNase I or -like enzymes.

CONCLUSION

Our data indicate that the elevated proliferation observed with increasing CIN severity and carcinoma was not paralleled by a similar increase in cell elimination. Most of the dysplastic and neoplastic cervical epithelial cells appeared incapable of entering terminal differentiation and complete it by apoptosis, possibly due to their failure to express or activate apoptosis executing enzymes.

Immunohistochemical visualization of histone H1 phosphorylation in squamous intraepithelial lesions of the gynecologic tract

Immunohistochemical staining was performed on gynecologic tract squamous intraepithelial lesions using a novel phosphorylation-specific monoclonal antibody (designated 12D11) that detects histone H1 when phosphorylated at a cyclin-dependent kinase (CDK)-responsive epitope. Findings were compared to immunostaining by MIB-1, an extensively studied antibody probe of proliferation. Routinely fixed and processed archival sections were subjected to distinct antigen retrieval and staining protocols for each antibody and were processed for immunodetection of either Ki-67 (with MIB-1) or phosphohistone H1, using a streptavidin-biotin kit and diaminobenzidine as chromagen. For 12D11 staining, antigen retrieval was performed at pH 4.0, and the antibody incubation buffer was supplemented with 1.0 M NaCl. Both 12D11 and MIB-1 stained parabasal cells in normal squamous epithelium. Staining by 12D11 and MIB-1 of cells in progressively higher strata was found to correlate with the severity of lesions. The mean proportion of positively stained cells was higher in MIB-1-stained sections than in 12D11-stained sections in normal squamous epithelium and in all grades of squamous intraepithelial lesions. We conclude that the changes in expression patterns of CDK-phosphorylated histone H1 in the spectrum of gynecologic squamous intraepithelial lesions are similar to staining patterns obtained with the proliferation probe MIB-1. The differing proportion of cells stained by MIB-1 and 12D11 suggests that phosphohistone H1 may be a useful alternative proliferation marker that detects a different subpopulation of cycling cells in premalignant squamous lesions.

How should we grade CIN?

How should we grade CIN? The grading of cervical intraepithelial neoplasia (CIN) is problematic. CIN represents a morphological continuum, but biopsies displaying this lesion are classified into two (e.g. Bethesda) or three grade categories, sometimes with poor reproducibility. There are also difficulties in reliably distinguishing low-grade CIN from its reactive simulants. Because of problems with inter- and intra-observer disagreement in the grading of CIN and the diagnosis of low-grade lesions, three expert contributions were commissioned to address the question 'how should we grade CIN?'.

Recent advances in immunohistochemistry in gynaecological pathology

Recent years have witnessed significant developments in the use of immunohistochemistry in diagnostic gynaecological pathology. This review details the most significant of these. In ovarian pathology, differential cytokeratin staining (CK7 and 20) assists in distinguishing between a primary ovarian adenocarcinoma and a metastatic adenocarcinoma, especially of colorectal origin. The development of markers characteristic of ovarian sex cord-stromal tumours (especially alpha-inhibin) facilitates diagnosis of these neoplasms which is often difficult by morphology alone due to the wide differential diagnosis. In the uterus, the distinction between a primary endometrial and endocervical adenocarcinoma may be facilitated by use of a small panel of antibodies, including CEA, ER and vimentin. Newly developed antibodies such as CD10 and h-caldesmon may be of use in the diagnosis of uterine mesenchymal lesions, especially in the distinction between endometrial stromal and smooth muscle lesions. Proliferation markers, such as MIB1, are of value in the cervix in the diagnosis of preinvasive squamous and glandular lesions. Recent studies have shown that cervical adenoma malignum exhibits a gastric phenotype. Advances have also been made in trophoblastic disease with the development of antibodies reactive against trophoblast such as alpha-inhibin, mel-Cam and p57. A newly developed monoclonal antibody HMGIC which is expressed in vulvovaginal aggressive angiomyxoma may prove to be of value in the often difficult distinction of this lesion from its histological mimics.

Proliferation in "atypical" atrophic pap smears

OBJECTIVE

Atrophic cervical epithelium of postmenopausal women may mimic high-grade cervical intraepithelial neoplasia (CIN2-3) in Papanicolaou-stained cervical smears (Pap smears). Women with such an "atypical" Pap smear need a repeated Pap smear after a course of estrogens before a definite diagnosis can be made. The aim of this study was to determine whether measurement of proliferative activity in Pap smears of postmenopausal patients that were difficult to interpret is a reliable test for differentiating between cervical atrophy and high-grade CIN.

METHODS

Pap smears obtained before and after estrogen treatment of 30 postmenopausal women with an atypical Pap smear were restained with the monoclonal antibody MIB1 to visualize proliferating cells. The proliferative activity index (PAI) was subsequently measured in order to explore the feasibility of a recently proposed PAI-based diagnostic decision tree to reduce the number of estrogen courses and follow-up Pap smears in postmenopausal women.

RESULTS

The PAI-based test to discriminate between cervical atrophy and high-grade CIN resulted in 100 and 96% correct diagnoses in women with high-grade CIN and cervical atrophy, respectively. Only 2 of the 30 women would have needed a repeated Pap smear after estrogen treatment for definite diagnosis if the PAI-based diagnostic decision had been used.

CONCLUSIONS

Measurement of PAI in MIB1 restained Pap smears is a simple, reliable, safe, and probably also cost-effective method to obtain a substantial reduction of diagnostic estrogen courses and subsequent Pap smears in postmenopausal women with an atypical Pap smear.

Ovarian endometriosis associated with ovarian carcinoma: a clinicopathological and immunohistochemical study

OBJECTIVE

The purpose of this study was to demonstrate the incidence, the histopathological characteristics, and the proliferation activity of endometriosis and atypical endometriosis associated with ovarian carcinoma.

METHODS

Microscopic slides of primary lesions from 127 patients with primary ovarian carcinoma were reviewed. The presence or absence of endometriosis and the transitions from typical endometriosis to atypical endometriosis and from atypical endometriosis to carcinoma were also histologically evaluated. Ki-67 immunoreactivity of typical and atypical endometriosis and carcinoma was examined. In addition, endometrial metaplasias were also evaluated.

RESULTS

Of the 127 patients, 37 had endometriosis: 70% (30/43) had clear cell adenocarcinoma, 43% (3/7) had endometrioid adenocarcinoma, 7% (4/60) had serous adenocarcinoma, and none (0/17) had mucinous adenocarcinoma. Thirty-three cases showed typical endometriosis and 29 cases had atypical endometriosis (25 cases had both). Tufting and the stratification of the lining epithelium were observed in 25 and 23 cases, respectively. The transition from typical endometriosis to atypical endometriosis was observed in 22 cases, and the transition from atypical endometriosis to carcinoma, in 23 cases. Only one case showed a direct transition from typical endometriosis to carcinoma. The mean Ki-67 indices were as follows: ovarian carcinoma, 23.1; atypical endometriosis, 9.9; typical endometriosis, 2.7. In 18 cases with metaplasia in endometriosis, eosinophilic metaplasia and ciliated metaplasia were the most common types. Five cases had two types of metaplasia.

CONCLUSIONS

Ovarian carcinomas, especially clear cell and endometrioid adenocarcinomas, are highly associated with endometriosis. Atypical endometriosis shows proliferation activity intermediate to those of typical endometriosis and ovarian carcinoma, suggesting it is a precancerous status.

Biomarkers as surrogates for cancer development

Biomarkers are routinely applied in the management of chronic diseases to reduce morbidity and mortality through early diagnosis, as well as to assess the necessity for, and responsiveness to, applied interventions. Biomarkers yield mechanistic insights into layers of biologic organization from molecule to organelle, to cell, and finally to cellular organization and tissue. A step-wise approach to the development of tissue-based biomarkers is presented. These biomarkers may serve as molecular targets for scientific inquiry and intervention, as well as approvable endpoints for clinical trials.

Decreased expression of Ki-67 in atrophic cervical epithelium of post-menopausal women

Papanicolaou-stained cervical smears (Pap smears) of post-menopausal women often present difficulties in distinguishing atrophic cervical epithelium from high-grade cervical intraepithelial neoplasia (CIN2-3). The aim of this study was to disclose differences in proliferative activity in normal cervical epithelium, cervical atrophy, and high-grade CIN lesions, in order to develop specific and sensitive classifiers to discriminate between cervical atrophy and high-grade CIN, both in cervical smears and in tissue sections. A case-control study was done on 83 patients. Proliferative activity was assessed in histological sections using the monoclonal antibody MIB1. An image analysis system was used to characterize different proliferation-associated features. Preceding Pap smears were restained with MIB1 and proliferative activity was measured by a point-counting procedure, carried out on a training set of 32 cases and a test set of 51 cases. In cervical atrophy, proliferative activity was significantly lower than in normal epithelium (p<0.001). Proliferative activity measured in both biopsies and cervical smears was considerably higher in high-grade CIN than in normal epithelium (p<0.001). Discriminant analyses resulted in four classifiers, based on proliferation parameters, to discriminate between cervical atrophy and high-grade CIN, and between CIN2 and CIN3, in biopsy specimens and cervical smears, respectively. The two classifiers for biopsy specimens resulted in 100% correct classification. Application of the classifier obtained from the training set of Pap smears resulted in 100% correct classification of the Pap smears in the test set. The classifier to discriminate between CIN2 and CIN3 in Pap smears, obtained from 36 patients, resulted in 87% and 90% correct classification, respectively.

Expression of topoisomerase II and Ki-67 in cervical carcinoma--clinicopathological study using immunohistochemistry

AIM

To study the correlation between the expression of topoisomerase II and Ki-67 antigen and disease outcome in cervical squamous cell carcinomas.

EXPERIMENTAL DESIGN

Forty-nine cervical carcinomas, 10 cases of high-grade cervical intraepithelial neoplasia (CIN II-III) and 5 control cervices were stained by monoclonal antibodies for topoisomerase II and Ki-67 (MIB-1 clone). Nuclear counts were correlated with patient age, tumor stage, histological grade and survival.

RESULTS

Thirteen patients died of disease, 35 remained free of disease, and one patient was lost to follow up. Ki-67 counts were higher in CIN lesions, when compared to both invasive carcinomas and control cervices. Topoisomerase II counts were comparable for CIN and invasive tumors. No immunoreactivity for topoisomerase was detected in control cases. Neither stage nor grade was associated with nuclear counts using either marker. In multivariate survival analysis, stage (p=0.001), grade (p=0.03) and older patient age (p=0.02) predicted poor survival. Ki-67 counts predicted survival with borderline significance (p=0.07), while topoisomerase II counts were not related to survival.

CONCLUSION

Ki-67 and topoisomerase II counts do not appear to have a significant role in the prediction of survival in cervical squamous cell carcinoma.