Possible role of adrenomedullin in the pathogenesis of tubal ectopic pregnancy

CONTEXT

Tubal ectopic pregnancy (tEP) is currently the leading cause of pregnancy-related deaths during the first trimester. Our current knowledge on the molecular pathogenesis is limited.

OBJECTIVE

The objective of the study was to find out the possible role of adrenomedullin (ADM) in the pathogenesis of tEP.

DESIGN

This was an experimental in vitro study on oviductal tissue.

SETTING

The study was conducted at a university teaching hospital.

PATIENTS AND INTERVENTIONS

Patients included those having oviducts removed surgically during salpingectomy for tEP or hysterectomy for benign gynecological conditions. Oviductal tissues were incubated in hormonal condition mimicking early pregnancy before used for in vitro experiments.

MAIN OUTCOME MEASURES

Plasma ADM concentration, oviductal expression of ADM and its receptors, ciliary beat frequency, smooth muscle contraction were measured.

RESULTS

The ciliary beat frequency and frequency of muscle contraction were lower in the oviducts from patients with tEP than those from simulated normal pregnancy. The plasma and oviductal tissue ADM levels were also lower. The decreases in ciliary beat and frequency of contraction were restored to normal after ADM treatment.

CONCLUSIONS

The results suggest that the lower ADM level in the oviducts of tEP may lead to the decrease in ciliary beating and muscle contraction, with the result that the embryo is retained and implanted in the oviduct. Our findings explain for the first time the etiology of tubal pregnancy on the basis of an impairment of the transport of the fertilized ovum resulting from an ADM deficiency and raise the possibility of using the plasma ADM level as a predictor for tubal ectopic pregnancy.

P-cadherin cooperates with insulin-like growth factor-1 receptor to promote metastatic signaling of gonadotropin-releasing hormone in ovarian cancer via p120 catenin

Gonadotropin-releasing hormone (GnRH) is a potent prometastatic factor in ovarian cancer, but the intracellular signaling events are not well understood. The classical Gα(q)-phospholipase C signal transduction pathway known to operate in the pituitary is not involved in GnRH actions at non-pituitary targets. Here we showed that GnRH treatment of ovarian cancer cells led to a rapid and remarkable tyrosine phosphorylation of p120 catenin (p120(ctn)), which was mediated by P-cadherin. The use of P-cadherin small interfering RNA or neutralizing antibodies to inhibit P-cadherin expression and function resulted in diminished p120(ctn) activation, confirming that the effect was P-cadherin specific. On exploring how P-cadherin, which lacks intrinsic kinase activity, might regulate the activation of p120(ctn), we found that P-cadherin could induce the ligand-independent activation of insulin-like growth factor-1 receptor (IGF-1R). Inhibition of IGF-1R expression or its activity significantly inhibited GnRH-induced p120(ctn) activation, and the subsequent cell migration and invasion. In addition, we showed that IGF-1R regulation by P-cadherin was associated with complex formation between IGF-1R and P-cadherin, and this regulation was also observed to be in vivo correlated with metastasis. Furthermore, using a mouse model of ovarian cancer metastasis, GnRH receptor knockdown was shown to diminish peritoneal dissemination of tumors and ascites formation. These findings suggest for the first time that GnRH can initiate an outside-in p120(ctn) signal transduction through the cross-talk between P-cadherin and IGF-1R, thus providing a novel molecular mechanism by which GnRH may control the high level of aggressiveness and invasion and metastasis potential that are characteristic of ovarian cancer.

Atypical glandular cells diagnosed during pregnancy and the postpartum period: a retrospective analysis

OBJECTIVES

The objective of the study was to determine the prevalence and clinical significance of atypical glandular cells (AGC) or atypical glandular cells of undetermined significance (AGUS) diagnosed in pregnant and postpartum women.

STUDY DESIGN

Smears having a diagnosis of AGC or AGUS, taken from pregnant and postpartum (within six weeks after delivery) women between 1995 and 2008 were reviewed and subclassified according to the Bethesda 2001 classification. Case records were then reviewed and a second cytology review was performed after disclosure of the follow-up data.

RESULTS

Among 91,133 smears taken from pregnant and postpartum women, 70 had AGC or AGUS (0.07%) diagnosed. Follow-up data were available in 40 cases, with mean duration of follow-up being 43 months. Among the 40 patients with follow-up data, nineteen had smears with coexisting squamous abnormalities. Thirty patients had positive pathology, including 18 (45%) cervical intraepithelial neoplasia III (CIN III), four (10%) cervical adenocarcinoma-in situ, three (7.5%) squamous cell carcinoma of cervix, four (10%) condylomas and one (2.5%) hydatidiform mole. On review, 24 out of 32 smears with AGC 'not otherwise specified' ('NOS') had significant pathology.

CONCLUSIONS

AGC found on cervical smears during pregnancy and the postpartum period is uncommon. The chance of having significant cervical pathology, however, is high and colposcopy should be performed.

Activated Stat3 expression in gestational trophoblastic disease: correlation with clinicopathological parameters and apoptotic indices

AIMS

To assess the expression profile of the activated form of signal transducer and activator of transcription (Stat)3 in gestational trophoblastic disease (GTD) and correlate the findings with clinicopathological parameters.

METHODS AND RESULTS

By immunohistochemistry, both cytoplasmic and nuclear expression of p-Stat3-Ser(727) was demonstrated in 88 trophoblastic tissues, including placentas and GTD. Nuclear immunoreactivity of p-Stat3-Ser(727) was significantly higher in hydatidiform mole (HM) (P < 0.001) and choriocarcinoma (P = 0.009) when compared with normal placentas. Placental site trophoblastic tumours (PSTT) and epithelioid trophoblastic tumours (ETT) also demonstrated higher nuclear p-Stat3-Ser(727) expression than their normal trophoblast counterparts. Higher p-Stat3-Ser(727) expression was confirmed in choriocarcinoma cell lines, JEG-3 and JAR, than in a normal trophoblast cell line, with both nuclear and cytoplasmic fractions demonstrated by immunoblotting. Spontaneously regressed HM showed significantly increased nuclear and cytoplasmic p-Stat3-Ser(727) immunoreactivity over those that developed gestational trophoblastic neoplasia (GTN) (P = 0.013, P = 0.039). There was a significant positive and inverse correlation between nuclear p-Stat3-Ser(727) immunoreactivity and apoptotic indices [terminal deoxynucleotidyl transferase (TdT)-mediated deoxyuridine triphosphate (dUTP) nick end labelling and M30 CytoDeath antibody] (P = 0.001, P < 0.001, Spearman's rho test) and Bcl-2 expression (P = 0.034), respectively.

CONCLUSIONS

p-Stat3-Ser(727) plays a role in the pathogenesis of GTD, probably through the regulation of apoptosis. p-Stat3-Ser(727) immunoreactivity is a potential marker in predicting GTN in HM.

Over-expression of FOXM1 transcription factor is associated with cervical cancer progression and pathogenesis

The Forkhead Box M1 (FOXM1) transcription factor plays a crucial role in regulating expression of cell cycle genes which are essentially involved in cell proliferation, differentiation and transformation. Recent studies have reported that aberrant expression of FOXM1 in a variety of human cancers is associated with their aggressive behaviour. However, the functional significance of FOXM1 in human cervical cancer is not known. We have shown that FOXM1 was significantly over-expressed in cervical squamous cell carcinoma (SCC) compared to normal cervical epithelium immunohistochemically (p < 0.001). In addition, intratumoural FOXM1 positivity was increased in cervical intraepithelial neoplasia (CIN) and carcinoma, compared with that in normal epithelium, indicating that FOXM1 is involved in tumour progression. Indeed, this is supported by clinicopathological analysis that the over-expression of FOXM1 was significantly associated with tumour late stage (p = 0.012) and cell proliferation marker, Ki67 (p < 0.001). Functionally, enforced expression of FOXM1c in FOXM1-deficient cervical cancer cells (C33A) remarkably enhanced cell proliferation and anchorage-independent growth ability. Conversely, depletion of FOXM1 by RNA interference in FOXM1-over-expressing cervical cancer cells (SiHa) caused significant inhibition on cell proliferation and anchorage-independent growth ability on soft agar. This inhibitory phenomenon was associated with the reduced expressions of cyclin B1, cyclinD1 and cdc25B but increased expression of p27(Kip1) and p21(Cip1). Our findings suggest a role for FOXM1 in the development and pathogenesis of human cervical SCC.

Methylation profile in benign, borderline and malignant ovarian tumors

PURPOSE

Promoter hypermethylation is a common phenomenon in neoplasm. The aims of this study were (a) to compare the methylation profiles in different types of ovarian tumors and (b) to determine the possible relationship between the methylation status and different clinicopathologic characteristics.

METHODS

We examined the promoter methylation status of 9 tumor suppressor genes (RARbeta2, TMS1, RIZ1, P15, P16, PTEN, MINT31, APC and HIC1) in 89 ovarian cancers, 16 borderline ovarian tumors, 19 benign ovarian tumors, 16 normal ovarian tissue and 5 ovarian cancer cell lines. The methylation status was examined with respect to clinicopathologic characteristics of the ovarian cancer patients.

RESULTS

Methylation indices for ovarian cancer, borderline ovarian tumor, benign ovarian tumor, normal ovarian tissue and ovarian cancer cell lines were 28.8, 20.1, 10.5, 11.8 and 42.2%, respectively. It was significantly higher in ovarian cancer, borderline ovarian tumor and ovarian cancer cell lines (X (2) test, P < 0.001, P = 0.01 and P < 0.001, respectively) than benign or normal ovarian tissues. In ovarian cancer, concurrent methylation of at least two genes (CM2) was associated with early stage disease (X (2) test, P = 0.035) and less recurrence (X (2) test, P = 0.020). When the methylation statuses of the nine genes as well as CM2 were included in multivariate Cox Regression analysis, CM2 was the only independent predictor for survival (P = 0.013).

CONCLUSION

CM2 was an independent predictor for survival in ovarian cancer.

Association of decreased mitochondrial DNA content with ovarian cancer progression

Mitochondrial DNA (mtDNA) content in ovarian carcinomas was assessed by quantitative PCR. Results show that mtDNA content in tumour cell was significantly higher than that in normal ovary. Change in mtDNA content was not related with patients' age or tumour stages. However, the average mtDNA copy number in pathological low-grade tumours was over two-fold higher than that in high-grade carcinomas (P=0.012). Moreover, type I carcinomas also had a significantly higher mtDNA copy number than in type II carcinomas (P=0.019). Change in mtDNA content might be an important genetic event in the progression of ovarian carcinomas.

Microsatellite instability in mitochondrial genome of common female cancers

To investigate the occurrence of mitochondrial genome instability in primary cervical, endometrial, ovarian, and breast carcinomas, we analyzed 12 microsatellite regions in mitochondrial DNA (mtDNA) of tumor tissues and their matched normal controls. Four of the 12 microsatellite markers starting at nucleotide position (np) 303, 514, 956, and 16184, respectively, exhibited instability as indicated by the change in length of short base-repetitive sequences of mtDNA in cancer tissue relative to that in control normal tissue from the same patient. About 25.4% of cervical cancers, 48.4% of endometrial cancers, 21.9% of ovarian cancers, and 29.4% of breast cancers carried one or more mitochondrial microsatellite instability (mtMSI). mtMSI was frequently detected in the D-loop region but rarely occurred in the coding region. A relatively long C tract interrupted by a T residue is the mtMSI hot spot in all four types of cancer studied. Different tumors have different mtMSI profiles. In particular, the frequency of mtMSI in endometrial cancer was significantly higher than in the other three types of cancer. Furthermore, carriers of a germ-line T to C polymorphism at np 16189 could be more susceptible to breast cancer development in light of the higher frequency detected in cancer patients than in normal individuals.

Differential Gene Expression Identified in Complete Hydatidiform Mole by Combining Suppression Subtractive Hybridization and cDNA Microarray

Complete hydatidiform mole (CHM) is a type of gestational trophoblastic disease with pure paternal chromosome contribution and unpredictable malignant potential. As an attempt to assess the molecular pathogenesis of CHM, suppression subtractive hybridization (SSH) combined with cDNA microarray was used to compare the gene expression pattern of CHM compared with normal first-trimester placenta of similar gestational ages. cDNA microarray analysis using tissue-specific chips constructed with subtracted cDNA libraries identified 13 differentially expressed gene transcripts. Quantitative real-time polymerase chain reaction (PCR) confirmed up-regulation of human chorionic gonadotropin beta subunit (CGB) (P=0.0008) and KIAA1200 (P=0.0005), a G-protein regulator, as well as down-regulation of osteopontin (SPP1) (P<0.0001) in 14 genotyped CHM when compared with 15 normal placentas. These candidate genes may contribute toward understanding the mechanism involved with the development and progression of CHM.

Single nucleotide polymorphisms of follicle-stimulating hormone receptor are associated with ovarian cancer susceptibility

Epidemiological studies suggested that ovulation was associated with ovarian carcinogenesis. Follicle-stimulating hormone (FSH) played an important role in follicular development and was recently found to affect growth of ovarian epithelial cells. Single nucleotide polymorphisms (SNPs) Thr307Ala and Asn680Ser were two non-synonymous variations in the coding region of the FSH receptor (FSHR) gene. This hitherto first case-control study investigating the association between these two FSHR SNPs and the risk of ovarian cancer involved 202 histopathologically confirmed ovarian cancer patients and 266 age-matched cancer-free control subjects using restriction fragment length polymorphism assay and direct sequencing. Our results demonstrated that the 307Ala and 680Ser carriers were associated with significantly increased risk of developing serous and mucinous types of ovarian cancers (P < 0.0005, OR = 2.60, 95% CI = 1.56-4.34; and P < 0.0005, OR = 2.89, 95% CI = 1.73-4.84, adjusted for age, respectively) but not endometrioid and clear cell types. The two SNPs were found to be in modest linkage disequilibrium, D' = 0.804 and 0.701, r2 = 0.581 and 0.406 for the cancer and control groups, respectively. The major haplotype of 307Ala-680Ser was also associated with higher cancer risk (P = 0.033, OR = 1.39, 95% CI = 1.03-1.88), especially for the serous and mucinous carcinomas (P = 0.001, OR = 1.82, 95% CI = 1.27-2.60). Our results suggested that the two FSHR SNPs might affect the susceptibility of women to specific subtypes of ovarian cancer. Different types of ovarian cancer might adopt distinct carcinogenetic pathways. Such understanding may be important in selecting patients for ovulation induction therapy.

Caspase activity is downregulated in choriocarcinoma: a cDNA array differential expression study

BACKGROUND

Placental trophoblast can be considered to be pseudomalignant tissue and the pathogenesis of gestational trophoblastic diseases remains to be clarified.

AIMS

To examine the role of caspases 8 and 10, identified by differential expression, on trophoblast tumorigenesis.

METHODS

cDNA array hybridisation was used to compare gene expression profiles in choriocarcinoma cell lines (JAR, JEG, and BeWo) and normal first trimester human placentas, followed by confirmation with quantitative real time polymerase chain reaction and immunohistochemistry. Caspase 10 and its closely related family member caspase 8 were analysed.

RESULTS

Downregulation of caspase 10 in choriocarcinoma was detected by both Atlastrade mark human cDNA expression array and Atlastrade mark human 1.2 array. Caspase 10 mRNA expression was significantly lower in hydatidiform mole (p = 0.035) and chorioarcinoma (p = 0.002) compared with normal placenta. The caspase 8 and 10 proteins were expressed predominantly in the cytotrophoblast and syncytiotrophoblast, respectively, with significantly lower expression in choriocarcinomas than other trophoblastic tissues (p < 0.05). Immunoreactivity for both caspase 8 and 10 correlated with the apoptotic index previously assessed by terminal deoxynucleotidyl transferase mediated dUTP nick end labelling (p = 0.02 and p = 0.04, respectively) and M30 (p < 0.001 and p = 0.003, respectively) approaches.

CONCLUSIONS

These results suggest that the downregulation of capases 8 and 10 might contribute to the pathogenesis of choriocarcinoma.

Effect of all-trans retinoic acid on tissue dynamics of choriocarcinoma cell lines: an organotypic model

BACKGROUND

All-trans retinoic acid (ATRA) is a natural vitamin A derivative that has a profound effect on the regulation of cell growth, differentiation and death.

AIM

To investigate the tissue dynamic and cellular invasion effects of ATRA in choriocarcinoma (CCA), an aggressive trophoblastic tumour, by using a three-dimensional organotypic culture model system and cell invasion assay, respectively.

METHODS

An organotypic culture model of two CCA cell lines, JAR and JEG, was established. The effects of 1 microM ATRA on proliferation, differentiation and apoptosis on this CCA model were assessed by morphological assessment of the mitotic and apoptotic figures as well as by Ki-67 and caspase-related M30 cytoDeath antibody immunohistochemistry and the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labelling (TUNEL) assay. The effect of ATRA on p53 and its regulated protein product, WAF1/Cip1, was also evaluated with DO7 and p21(WAF1) antibodies, respectively. Moreover, the effect of ATRA on cellular (CCA) invasion was also investigated with Cell Invasion Kit on the JEG cell line.

RESULTS

ATRA was found to induce marked apoptosis in organotypic cultures of both cell lines, as evidenced by increased M30-positive cells (p<0.0001) and increased TUNEL-positive cells (p<0.0001) in treated cultures; to decrease proliferation, as evidenced by decreased Ki-67-positive cells (p<0.0001); and to decrease p53-DO7 immunoreactivity (p<0.0001) and increase p21(WAF1) (p<0.0001) immunoreactivity. 1.5 microM ATRA was found to effectively inhibit JEG cell invasion in the cell invasion assay.

CONCLUSION

ATRA treatment was found to inhibit invasion and proliferation and enhance apoptosis, probably by the activation of caspases and induction of differentiation. ATRA and synthetic retinoids may be alternative agents for the treatment of CCA.

Id helix-loop-helix proteins are differentially expressed in gestational trophoblastic disease

AIMS

To assess the expression of Id proteins in trophoblastic tissues and to correlate this with clinical parameters, proliferative and apoptotic indices as well as to related oncogene expression.

METHODS AND RESULTS

Immunohistochemistry for Id1, Id2, Id3 and Id4 was performed on 83 trophoblastic tissues including 17 normal first-trimester placentas, seven term placentas, 47 hydatidiform moles (HM), and 12 spontaneous miscarriages. The four Id proteins were predominantly expressed in the villous and implantation site intermediate trophoblast. Expression of Id1 in HM was significantly higher than that in normal placenta (P = 0.0006) and spontaneous miscarriage (P = 0.0001) but did not correlate with subsequent development of gestational trophoblastic neoplasia (GTN). Id1 expression correlated with the proliferation index as assessed by MCM7 (P = 0.003) and Ki67 (P = 0.017) and with the apoptotic activity assessed by TUNEL (P = 0.001) and M30 CytoDeath antibody (P = 0.013). Moreover, the expression of Id1 correlated with the expression of p53 (P = 0.004), p21(WAF1) (/CIP1) (P = 0.003) but not with p16 (P = 0.107).

CONCLUSIONS

Id proteins may play a role in the regulation of proliferative and apoptotic activity in trophoblastic tissue and are potentially useful in differentiating molar and non-molar gestation, but are not helpful in predicting GTN.

Replicative MCM7 protein as a proliferation marker in endometrial carcinoma: a tissue microarray and clinicopathological analysis

AIMS

To assess, in tissue microarray (TMA), the proliferative activity of endometrial carcinoma using one of the minichromosome maintenance (MCM) proteins (MCM7), and to explore its potential value for prognosis. MCM proteins are essential for eukaryotic DNA replication and have recently been used to define the proliferative compartments in human tissues.

METHODS AND RESULTS

Immunohistochemistry for MCM7 and Ki67 was performed on TMAs constructed from 212 cases of endometrial carcinoma. MCM7 and Ki67 expression was quantified according to the extent of nuclear staining. An analysis was carried out of the association between MCM7 expression and that of Ki67 and the clinicopathological characteristics of endometrial carcinoma. MCM7 and Ki67 immunoreactivity was clearly evident in the nuclei of tumour cells. MCM7 and Ki67 labelling indices in endometrial carcinomas correlated with each other (P < 0.001). A significant correlation existed between the MCM7 labelling index and histological grade (P = 0.008) and patients' age at diagnosis (P < 0.001). Well-differentiated carcinomas and younger patients had a lower MCM7 index. Poor survival was observed in patients with endometrial carcinoma with a high MCM7 index (P = 0.03) and MCM7 was found to be an independent prognostic factor by multivariate analysis (P = 0.04). The Ki67 labelling index correlated with histological grade (P = 0.01) but had no significant prognostic impact (P = 0.50).

CONCLUSIONS

In this TMA study on endometrial carcinoma, MCM7 was found to be a more reliable and useful marker than Ki67 in assessing tumour proliferation and in the prognosis of patients.

Chromosome in situ hybridisation, Ki-67, and telomerase immunocytochemistry in liquid based cervical cytology

AIMS

To assess the potential value of chromosome in situ hybridisation (CISH), Ki-67, and telomerase immunocytochemistry in liquid based cervical cytology to help detect carcinoma cells and precursors.

METHOD

Sixty ThinPrep processed cervical cytology samples were studied: 23 cases within the normal limit, 13 low grade squamous intraepithelial lesions (LSILs), 10 high grade squamous intraepithelial lesions (HSILs), six squamous cell carcinomas, three endocervical adenocarcinomas, two cervical adenosquamous cell carcinomas, and three endometrial adenocarcinomas. CISH was performed with DNA probes specific for the pericentromeric regions of chromosome 11 and 16. Hybridisation signals were visualised with the streptavidin-biotin peroxidase technique. The monoclonal MIB1 and polyclonal TRT-H231 antibodies were used to detect Ki-67 and telomerase immunoreactivity, respectively.

RESULTS

Non-specific background staining was almost absent in CISH slides. Normal squamous and glandular cells showed a diploid chromosomal pattern. A relative gain in chromosomes 11 and 16 (aneusomy) was seen in HSIL and the carcinomas (p<0.0001). In MIB1 stained smears, normal cells and koilocytes showed inconspicuous immunoreactivity, whereas strongly immunoreactive nuclei were found in cancer cells and HSIL (p<0.0001). Not only carcinoma and HSIL cells, but also some normal cells, showed cytoplasmic staining for telomerase.

CONCLUSIONS

These preliminary results indicate that ThinPrep processed cervical smears are suitable for CISH and immunocytochemical studies. The neoplastic squamous and glandular cells were easily identified based on nuclear aneusomy and strong Ki-67 immuoreactivity in the context of abnormal nuclear morphology. This is the first study to apply CISH in cervical cytology using an immunoenzymatic approach.

Detection of hypermethylated genes in tumor and plasma of cervical cancer patients

OBJECTIVE

The aim of this study is to investigate the prevalence of promotor CpG island methylation of the death-associated protein kinase (DAPK), p16, and O(6)-methylguanine-DNA methyltransferase (MGMT) genes in both tumor and plasma samples of cervical cancers.

METHODS

Methylation-specific PCR (MSP) was employed to detect promotor CpG island methylation of the DAPK, p16, and MGMT genes in 85 surgical tumor tissue samples and 40 pretreatment plasma samples from cervical cancers.

RESULTS

Promotor CpG island methylation of DAPK, p16, and MGMT was detectable, respectively, in 60%, 28.2%, and 18.8% of cases of cervical tumor DNA; and in 40%, 10%, and 7.5% of cases of patients' plasma DNA. Moreover, at least one of the three methylated genes was detected in 75.3% (64/85) of cases of tumor and in 55% (22/40) of cases of plasma. Higher prevalence of methylation of DAPK was found in squamous cell carcinoma than in adenocarcinoma in both univariate and multivariate analysis. Methylation of p16 was significantly associated with that of MGMT in both univariate and multivariate analysis. The methylation pattern in primary tumor and plasma was found to be concordant in 23 patients with matched tissue and plasma samples. In cases positive for DAPK and p16 methylation in tumor, detection in the paired plasma sample was 64.3% (9/14) and 33.3% (3/9), respectively.

CONCLUSIONS

Promotor CpG island methylation is a frequent event in cervical carcinogenesis. Detection of the methylated sequences in the circulation suggests that plasma DNA methylation warrants further study to determine its potential role in cancer management.

A retrospective review on atypical glandular cells of undetermined significance (agus) using the Bethesda 2001 classification

OBJECTIVE

The Bethesda system for reporting cervicovaginal cytologic diagnoses was recently revised in 2001. Pathologists are required to report not only whether the smear favors neoplastic changes, but also the origin of the abnormal cells. In this study, archival smears were reviewed to evaluate the usefulness of the new classification.

METHODS

Smears having atypical glandular cells taken between January 1995 and December 1997 were reviewed and subclassified according to the revised Bethesda classification. Case records were then reviewed and cases with discrepancies between the cytological evaluation and corresponding final histological diagnoses were further reviewed.

RESULTS

There were 138 smears reviewed. The mean age of the patients was 47 (range, 18 to 78). Thirty-four smears favored neoplasia and 104 favored "NOS" ("not otherwise specified"). Sixty smears favored endocervical origin and 78 endometrial origin. Forty-three patients (31%) had significant pathologies, including 12 (8.7%) patients with high-grade CIN, 2 (1.4%) with low-grade CIN, 5 (3.6%) with HPV infection, 7 (5.1%) with carcinoma of the corpus, 1 (0.7%) with cervical adenocarcinoma in situ, 4 (2.9%) with adenocarcinoma of the cervix, 3 (2.2%) with endometrial hyperplasia, and 5 (3.6%) with carcinoma of the ovary. Two (1.4%) patients had double primary female genital malignancies and 2 patients (1.4%) had extragenital malignancies. Significant correlation was found between smears "favor neoplasia" and a final diagnosis with significant pathology (chi(2) test, P < 0.05). Significant association was found between AGC favored endocervical origin and a final diagnosis with cervical diseases (chi(2) test, P < 0.05). Four of the 43 patients who had significant pathologies had lesions found during their subsequent visits and all of them had cervical smears classified as AGC "favor neoplasia".

CONCLUSION

AGC found on cervical smears are an indication for early and intensive investigation.

Methylation status and expression of E-cadherin and cadherin-11 in gestational trophoblastic diseases

The clinical significance of cadherins in gestational trophoblastic diseases (GTD) is not fully understood. In this study, the expression of E-cadherin and cadherin-11 in 12 normal placentas, 32 cases of hydatidiform mole (HM) including 15 complete HMs and 17 partial HMs, and five choriocarcinomas was investigated by immunohistochemistry and correlated with follow-up of HMs. Cases with available frozen blocks were further analyzed by western blot and semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR). Methylation of E-cadherin was investigated by methylation-specific PCR in six normal first trimester placentas, 19 HMs and their associated deciduas. E-cadherin expression was localized to cytotrophoblast and intermediate trophoblast whereas cadherin-11 was expressed in syncytiotrophoblast, intermediate trophoblast, and decidua. Immunoreactivity of E-cadherin was reduced in choriocarcinoma and complete HM when compared with that in normal first trimester placenta (P < 0.01, P = 0.04). Hypermethylation of E-cadherin was demonstrated in three complete HMs with the lowest level of E-cadherin. Compared with normal first trimester placenta, immunoreactivity of cadherin-11 was higher in complete HM (P = 0.02), but lower in choriocarcinoma (P = 0.02). Such differential expression was confirmed by western blot and semiquantitative RT-PCR. No obvious association was observed between the development of persistent trophoblastic disease with the expression of E-cadherin and cadherin-11.

Minichromosome maintenance protein 7 expression in gestational trophoblastic disease: correlation with Ki67, PCNA and clinicopathological parameters

AIMS

To assess the proliferative activity of gestational trophoblastic disease (GTD) using one of the novel proliferation markers (MCM7) and to determine its prognostic value in hydatidiform mole (HM).

METHODS AND RESULTS

Immunohistochemical staining for MCM7 was performed on 122 samples of paraffin-embedded trophoblastic tissues including 22 normal first-trimester placentas, 12 term placentas, 12 spontaneous miscarriages (SM), 21 partial moles (PM), 44 complete hydatidiform moles (CM), and 11 choriocarcinomas (CCA). The correlations between the proliferative indices assessed by MCM7, proliferating cell nuclear antigen (PCNA) and Ki67 (MIB1) immunoreactivity as well as clinical progress were assessed. MCM7 immunoreactivity was found predominantly in the nuclei of cytotrophoblast and intermediate trophoblast and decreased with placental maturation. MCM7 expression was highest in CCA, followed by CM, PM, normal first-trimester placenta, SM and term placenta. MCM7 index was significantly higher in PM and CM than in SM (P = 0.007, P < 0.001) but not between PM and CM themselves (P = 0.560). Eighteen of the 65 patients with HM developed persistent trophoblastic disease (PTD) requiring chemotherapy. There was no significant difference in MCM7 indices between the patients who developed PTD and those who did not (P = 0.312). MCM7 indices correlated well with Ki67 (P = 0.002) but not with PCNA (P = 0.054) indices. MCM7 indices demonstrated less variability than PCNA and Ki67 and may be a better proliferation marker than the latter two.

CONCLUSIONS

We conclude that MCM7 is useful in differentiating molar and non-molar gestations but is not helpful in discriminating PM from CM or in predicting PTD.

Methylation status and expression of E-cadherin and cadherin-11 in gestational trophoblastic diseases

The clinical significance of cadherins in gestational trophoblastic diseases (GTD) is not fully understood. In this study, the expression of E-cadherin and cadherin-11 in 12 normal placentas, 32 cases of hydatidiform mole (HM) including 15 complete HMs and 17 partial HMs, and five choriocarcinomas was investigated by immunohistochemistry and correlated with follow-up of HMs. Cases with available frozen blocks were further analyzed by western blot and semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR). Methylation of E-cadherin was investigated by methylation-specific PCR in six normal first trimester placentas, 19 HMs and their associated deciduas. E-cadherin expression was localized to cytotrophoblast and intermediate trophoblast whereas cadherin-11 was expressed in syncytiotrophoblast, intermediate trophoblast, and decidua. Immunoreactivity of E-cadherin was reduced in choriocarcinoma and complete HM when compared with that in normal first trimester placenta (P < 0.01, P = 0.04). Hypermethylation of E-cadherin was demonstrated in three complete HMs with the lowest level of E-cadherin. Compared with normal first trimester placenta, immunoreactivity of cadherin-11 was higher in complete HM (P = 0.02), but lower in choriocarcinoma (P = 0.02). Such differential expression was confirmed by western blot and semiquantitative RT-PCR. No obvious association was observed between the development of persistent trophoblastic disease with the expression of E-cadherin and cadherin-11.

Specific expression of VCY2 in human male germ cells and its involvement in the pathogenesis of male infertility

Abnormal spermatogenesis in men with Y-chromosome microdeletions suggests that genes important for spermatogenesis have been removed from these individuals. VCY2 is a testis-specific gene that locates in the most frequently deleted azoospermia factor c region in the Y chromosome. We have raised an antiserum to VCY2 and used it to characterize the localization of VCY2 in human testis. Using Western blot analysis, the affinity-purified polyclonal VCY2 antibody gave a single specific band of approximately 14 kDa in size, corresponding to the expected size of VCY2 in all the collected human testicular biopsy specimens with normal spermatogenesis. Immunohistochemical analyses showed that VCY2 localized to the nuclei of spermatogonia, spermatocytes, and round spermatids, except elongated spermatids. At the ultrastructural level, VCY2 expression was found in the nucleus of human ejaculated spermatozoa. To determine the possible relationship of VCY2 with the pathogenesis of male infertility, we examined a group of infertile men with and without Y-chromosome microdeletions and with known testicular pathology using VCY2 antibody. VCY2 was weakly expressed at the spermatogonia and immunonegative in spermatocytes and round spermatids in testicular biopsy specimens with maturation arrest or hypospermatogenesis. The specific localization of the protein in germ cell nuclei indicates that VCY2 is likely to function in male germ cell development. The impaired expression of VCY2 in infertile men suggests its involvement in the pathogenesis of male infertility.

High frequency of mitochondrial genome instability in human endometrial carcinomas

To investigate the occurrence of somatic mitochondrial DNA (mtDNA) mutations in human primary endometrial carcinomas, we sequenced the D-loop region, the 12S and 16S rRNA genes of mtDNA of cancer tissues and their matched normal controls. About 56% (28 out of 50) of cases carry one or more somatic changes in mtDNA including deletion, point mutation and mitochondrial microsatellite instability (mtMSI), namely the change in length of short base-repetitive sequences of mtDNA. In particular, mtMSI was frequently detected in 89% (25 out of 28) of all the cases carrying somatic changes followed by point mutations (25%; seven out of 28) and deletion (3.5%; one out of 28). The CCCCCTCCCC sequences located in the Hypervariable Regions I and II of the D-loop and 12S rRNA gene are instability hot spot regions in endometrial carcinomas. It is suggested that errors in replication may account for the high frequency of mtMSI in human endometrial carcinomas. The relatively high prevalence of mtMSI may be a potential new tool for detection of endometrial cancer.

Expression of e-cadherin and beta-catenin in trophoblastic tissue in normal and pathological pregnancies

E-cadherin and beta-catenin are cell-cell adhesion molecules, which are thought to play an important role in trophoblastic differentiation and remodelling during gestation. Their expression may be altered in pathological conditions with trophoblastic invasion. In this study, we used immunohistochemical methods to study the pattern of expression of E-cadherin and beta-catenin in villous trophoblastic tissue in normal and pathological pregnancies. In villous trophoblastic tissue, E-cadherin had a membranous distribution, whereas beta-catenin had a mixed-membranous and granular cytoplasmic distribution. The levels of expression of E-cadherin and beta-catenin correlated with each other. From first to third trimesters, the expression of both E-cadherin and beta-catenin showed a decreasing trend. In preeclampsia, there was an up-regulation of E-cadherin and beta-catenin expression. In placenta accreta, the level of expression of both did not differ from that in normal third-trimester placenta. In gestational trophoblastic diseases, there was a general trend of down-regulation of both E-cadherin and beta-catenin. Altered expression of E-cadherin and beta-catenin may play a role in the development of normal and pathological placentas.

Detection of human papillomavirus DNA in malignant lesions from Chinese women with carcinomas of the upper genital tract

OBJECTIVE

The aim of this study was to determine the prevalence of high-risk oncogenic human papillomaviruses (HPVs) in malignant lesions from Hong Kong Chinese women with carcinomas of the upper genital tract.

METHODS

The presence of high-risk HPVs in 55 cases of endometrial adenocarcinomas and 60 cases of primary epithelial ovarian cancers was detected by polymerase chain reaction (PCR) using consensus primers complementary to late 1 (L1) gene of the genital HPVs. Amplified PCR products were verified and typed by Southern blot analysis using (32)P-labeled DNA probes prepared from cloned HPV-16 and -18 plasmids. To confirm the presence of high-risk HPV types in the tumor tissues, PCR amplification using HPV type 16- and 18-specific primers for part of the E6 gene were also carried out.

RESULTS

While HPV-18 was not detected, HPV-16 DNA sequences were identified in 5 (9.1%) of the 55 studied endometrial carcinoma samples. Of the 5 HPV-16-positive cases, there were 4 stage I, and 1 stage II endometrial cancer. In addition, 6 (10%) of the 60 epithelial ovarian carcinomas were positive for high-risk HPVs, which included 5 cases with HPV-16 and 1 case with HPV-18. Clinical staging revealed that 5 of the 6 HPV-positive cases were stage I and the remaining case was stage III ovarian cancer. Histology of the 6 HPV-positive cases showed that there were 1 case of clear-cell adenocarcinoma, 1 case of mucinous cystadenocarcinoma, and 4 cases of mucinous tumor of borderline malignancy. No other HPV types were detected.

CONCLUSION

High-risk HPV was detected in approximately 10% of the tumor samples from women with upper genital tract carcinomas. As compared to the high positive rate of HPV infections in cervical cancer, it appears that HPV infection plays a relatively minor role in the pathogenesis of endometrial and ovarian carcinomas.

Current understandings of the molecular genetics of gestational trophoblastic diseases

Gestational trophoblastic disease (GTD) is a heterogeneous group of diseases characterized by abnormally proliferating trophoblastic tissues. This includes partial and complete hydatidiform moles, invasive mole, choriocarcinoma and placental site trophoblastic tumour. Cytogenetic studies revealed that hydatidiform moles contain either solely (as in complete moles) or an excess (as in partial moles) of paternal contribution to the genome. Genomic imprinting is believed to play a pivotal role in the pathogenesis of hydatidiform moles. However its precise role and mechanism remains poorly understood. Hydatidiform mole carries a potential of malignant transformation. Similar to other human cancers, malignant transformation in gestational trophoblastic tumours is likely a multistep process and involves multiple genetic alterations including activation of oncogenes and inactivation of tumour suppressor genes. In addition, expression of telomerase activity, altered expression of cell--cell adhesion molecules and abnormal expression of matrix metalloproteinases have also been reported in GTD. These represent disruption of the delicate balance and regulation of cellular processes including proliferation, differentiation, apoptosis and invasion. The significance of these alterations in the pathogenesis and malignant transformation of gestational trophoblastic diseases is reviewed in this paper.

Immunohistochemical and mutational analysis of p53 tumor suppressor gene in gestational trophoblastic disease: correlation with mdm2, proliferation index, and clinicopathologic parameters

The role of p53 in the pathogenesis of gestational trophoblastic disease (GTD) was investigated. Immunohistochemical studies for p53, its regulator mdm2, and proliferation marker Ki67 were performed on paraffin-embedded tissues of 28 partial moles (PM), 57 complete moles (CM), 14 choriocarcinomas (CCA), and 31 normal placentas. Three antibodies to p53 (DO-7, Ab-2, Ab-3) were used and demonstrated immunoreactivity for wild-type p53 protein predominantly in the nuclei of cytotrophoblasts. Direct DNA sequencing of 36 hydatidiform moles using frozen tissues confirmed an absence of mutational changes in exons 5-8. CCA was found to have the highest p53 protein expression, followed by CM, PM, and normal placenta (P < 0.001). In normal placentas (P = 0.0001), PM, and CM (P = 0.016), an inverse correlation between their gestational age and p53 expression was observed. p53 expression was found to correlate with proliferation index in normal placenta (P = 0.0001) and all three groups of GTD (P = 0.012). Significant correlation between p53 and mdm2 expression was also observed (P < 0.01). The distinctive expression of p53 wild-type protein in the cytotrophoblasts and its positive correlation with the proliferative index suggests that its overexpression in GTD may be related to its effect on cell proliferation. The parallel expression of mdm2 and p53 also supports the presence of an autoregulatory feedback loop in the control of this process. No correlation could be found between clinical progress of the patients with hydatidiform moles, and the p53 (P = 0.78) or mdm2 protein (P = 0.54) expression suggesting that neither of them carries any prognostic significance.