The prognostic value of PTEN, p53, and beta-catenin in endometrial carcinoma: a prospective immunocytochemical study

An Overview of Endometrial Cancer with Novel Therapeutic Strategies

Endometrial cancer (EC) stands as the most prevalent gynecologic malignancy. In the past, it was classified based on its hormone sensitivity. However, The Cancer Genome Atlas has categorized EC into four groups, which offers a more objective and reproducible classification and has been shown to have prognostic and therapeutic implications. Hormonally driven EC arises from a precursor lesion known as endometrial hyperplasia, resulting from unopposed estrogen. EC is usually diagnosed through biopsy, followed by surgical staging unless advanced disease is expected. The typical staging consists of a hysterectomy with bilateral salpingo-oophorectomy and sentinel lymph node biopsies, with a preference placed on a minimally invasive approach. The stage of the disease is the most significant prognostic marker. However, factors such as age, histology, grade, myometrial invasion, lymphovascular space invasion, tumor size, peritoneal cytology, hormone receptor status, ploidy and markers, body mass index, and the therapy received all contribute to the prognosis. Treatment is tailored based on the stage and the risk of recurrence. Radiotherapy is primarily used in the early stages, and chemotherapy can be added if high-grade histology or advanced-stage disease is present. The risk of EC recurrence increases with advances in stage. Among the recurrences, vaginal cases exhibit the most favorable response to treatment, typically for radiotherapy. Conversely, the treatment of widespread recurrence is currently palliative and is best managed with chemotherapy or hormonal agents. Most recently, immunotherapy has emerged as a promising treatment for advanced and recurrent EC.

PTEN Deficiency in Tubo-Ovarian High-Grade Serous Carcinoma is Associated with Poor Progression-Free Survival and is Mutually Exclusive with CCNE1 Amplification

As a critical tumor suppressor, PTEN has gained much attention in cancer research. Emerging evidence suggests an association between PTEN status and clinical outcome in certain tumors, and may be predictive of response to several therapies. However, the significance of PTEN deficiency in tubo-ovarian high-grade serous carcinomas (HGSCs) is still poorly understood. We evaluated PTEN expression in HGSCs and determined its clinical relevance. A cohort of 76 HGSC specimens was profiled using tissue microarray. Immunohistochemistry (IHC) of PTEN, ER, PR, AR, CD8, FOXP3, and PD-L1 was performed. Targeted gene panel testing by massively parallel sequencing was performed in 51 cases. PTEN deficiency (complete or subclonal loss) detected by IHC was identified in 13 of the 62 HGSCs (21%) and was significantly correlated with reduced expression of ER and worse first progression-free survival (P < .05) but not with PD-L1 expression, the density of intratumoral T lymphocytes, or overall survival. In our cohort, tumor progression within 1 year of PARP inhibitor therapy was found more frequently in PTEN-deficient cases than in PTEN-intact cases (100% vs 52%). Molecular profiling showed that intragenic mutation or deletion was not the predominant mechanism for PTEN inactivation in HGSCs. In addition, CCNE1 amplification was found to be mutually exclusive with PTEN deficiency at both protein and DNA levels. An analysis of the genomic data from 1702 HGSC samples deposited with The Cancer Genome Atlas database obtained from cBioPortal confirmed the low rate of detection of PTEN gene alterations and the mutually exclusive nature of PTEN loss and CCNE1 amplification in HGSCs. These findings indicate that PTEN deficiency defines a distinct clinically significant subgroup of HGSCs with a tendency for ER negativity, wild-type CCNE1 status, inferior clinical outcomes, and potential drug resistance. These tumors may benefit from PI3K pathway inhibitors in combination with other ovarian cancer regimens, which deserves further investigation.

Nuclear Expression of β-Catenin Is Associated with Improved Outcomes in Endometrial Cancer

Beta-catenin is involved in intercellular adhesion and participates in the Wnt signaling pathway. This study evaluated the expression pattern and prognostic value of β-catenin in a series of endometrial carcinoma patients. Immunohistochemical analyses were used to assess the expression and subcellular localization of β-catenin from tissue sections of 74 patients with endometrial carcinoma. No correlation was found between beta-catenin expression and clinicopathological parameters. Patients expressing nuclear β-catenin (n = 13; 16%) showed a more favorable prognosis than patients expressing membranous β-catenin; the 5-year disease-related survival rate was 100% for cases expressing nuclear β-catenin, compared with 73.8% (SE 0.08) of cases expressing membranous β-catenin (p = 0.04). Although statistical significance was not reached (p = 0.15), cases expressing nuclear β-catenin showed a 5-year disease-free survival rate of 90.9% (SE 0.08) compared with 67.4% (SE 0.08) of cases expressing membranous β-catenin. Univariate Cox analysis revealed that membranous β-catenin expression was found to be associated with a relative risk of death of 33.9 (p = 0.04). The stage of disease (p = 0.0006), histology (p = 0.003), and grading (p = 0.008) were also significantly correlated with disease-free survival according to univariate Cox analyses. Determining β-catenin expression and localization patterns may predict survival in patients with endometrial cancer and, therefore, should be considered a potential prognostic marker of disease.

Relationship between polycomb-group protein BMI-1 and phosphatases regulating AKT phosphorylation level in endometrial cancer

The PI3K/AKT pathway is frequently activated in endometrial carcinoma. BMI‐1 (B‐lymphoma Mo‐MLV insertion region 1) protein affects expression of PTEN (phosphatase and tensin homolog) in some cancers, but its significance for endometrial tumorigenesis is not known. The objective of this study was to determine the relationship between BMI‐1 and expression of factors affecting AKT (protein kinase B) phosphorylation level in endometrial cancer. The expression of proteins and mRNAs was investigated in endometrial cancer specimens and samples of non‐neoplastic endometrial tissue by Western blot and RT‐PCR, respectively. The impact of BMI‐1 down‐regulation on AKT phosphorylation and expression of genes coding for several phosphatases were studied in HEC1A cells. The results showed that BMI‐1 depletion caused increase in PHLPP1 and PHLPP2 (PH domain and leucine‐rich repeat protein phosphatases 1/2) expression and decrease in phospho‐AKT (pAKT) level. In more advanced tumours with higher metastatic potential, the expression of BMI‐1 was lower compared to tumours less advanced and without lymph node metastasis. There were significant inverse correlations between BMI‐1 and PHLPPs, especially PHLPP1 in normal endometrial samples. The inverse correlation between BMI‐1 and PHLPP1/PHLPP2 expression was observed in PTEN positive but not PTEN negative cancers. Low PHLPP2 expression in tumours predicted poorer overall survival. BMI‐1 impacts on AKT phosphorylation level in endometrial cells by regulation of PHLPP expression.

Recent advances in endometrial cancer: a review of key clinical trials from 2015 to 2019

In the past few years, we have seen several important advances in understanding of and therapy for endometrial cancer. This review highlights key recent abstracts and publications in endometrial cancer from 2015 to 2019. We focus on clinical trials in surgical staging and the utility of sentinel lymph node mapping, adjuvant treatment for high-risk disease and HER2/neu-positive serous tumors, combination therapy for recurrent disease, molecular biology, and immunotherapy.

Expression of p53 and PTEN in human primary endometrial carcinomas: Clinicopathological and immunohistochemical analysis and study of their concomitant expression

Endometrial carcinoma is a common malignancy of the female genital tract. Alterations in the expression levels of various oncogenes and tumor suppressor genes serve important roles in the carcinogenesis and biological behavior of endometrial carcinoma. The aim of the present study was to evaluate the combination and individual expression of p53 and phosphatase and tensin homolog (PTEN) protein in human endometrial carcinoma. In addition, the correlation of these proteins with clinicopathological parameters was also assessed. Retrospective immunohistochemical analysis of the expression of p53 and PTEN tumor suppressor proteins was conducted in 99 women with endometrial carcinoma. The overall rate of p53 and PTEN positivity was 89 and 77%, respectively, according to the sum of stain intensity and scores of immunopositive cells. The sum of p53 positivity correlated strongly with PTEN expression (ρ=0.256; P=0.044). The concomitant sum of p53 and PTEN expression was identified in 45% of patients with endometrial adenocarcinoma. Notably, the sum of the immunohistochemical expression of p53 was significantly correlated with patient age (P=0.037), histologic type (P=0.008), histologic grade (P=0.002) and fallopian and/or ovarian invasion (P=0.014). Furthermore, PTEN expression was associated with myometrial invasion (ρ=−0.377; P=0.002) and clinical stage (P=0.019). In addition, concomitant p53 and PTEN expression was correlated with patient age (P=0.008) and histologic differentiation (P=0.028). The findings indicated a correlation between the expression of p53 and PTEN in endometrial adenocarcinoma, which suggested an intrinsic association between expression levels of these tumor suppressor genes. The study also suggested that concomitant p53 and PTEN expression contributed in characterizing the tumor behavior of endometrial carcinoma. Taken together, the present study suggested the combined expression of p53 and PTEN in the development of high-grade endometrial carcinoma in older patients. In addition, the findings indicated activation of different molecular pathways in the tumor progression between low-grade and high-grade endometrial carcinomas.

Concomitant p53 and PTEN immunoexpression to predict the risk of malignancy in endometrial polyps

The aim of this retrospective cross-sectional study was to assess the usefulness of phosphase and tensin homolog deleted on chromosome 10 (PTEN) and p53 protein immunoexpression in predicting the risk of malignancy in endometrial polyps. The study was conducted at tertiary public hospital, university teaching center, and private practice clinic.A total of 159 patients with endometrial polyps who underwent hysteroscopic polypectomy between January 2010 to December 2014 were included. p53 and PTEN immunoexpression were assessed in histologic endometrial polyp samples. Patients were allocated into 2 groups: group A, endometrial polyps without atypia (120), and group B, endometrial polyps with atypia (39), which were subdivided into A1 (80) and B1 (21) = p53-/PTEN+ immunostaining; A2 (20) and B2 (11) = p53+/PTEN+; A3 (14) and B3 (4) = p53+/PTEN-; A4 (6) and B4 (3) = p53-/PTEN-.There was no significant difference between groups regarding clinical and epidemiologic parameters, except for age. Neoplasia incidence within groups was higher when at least 1 marker was abnormally stained (in group A, P = .0089, odds ratio [OR] = 13.94 [1.62; 120.27]; in group B, P = .0255, OR 12.73 [1.38; 117.27]). Overall neoplasia incidence was higher in group B than in group A (20.5% vs 5.8%; P = .0113). Malignant neoplasia was found more frequently in patients with p53+ (P = .0006, OR = 7.67 [2.30; 25.54]) and PTEN- (P = .0043; OR = 5.43 [1.77; 16.61]).Immunohistochemical analysis using p53 and PTEN as markers, either alone or concomitantly, can be useful to predict malignant transformation in cases of endometrial polyps.

CTNNB1 (beta-catenin) mutation identifies low grade, early stage endometrial cancer patients at increased risk of recurrence

Although the majority of low grade, early stage endometrial cancer patients will have good survival outcomes with surgery alone, those patients who do recur tend to do poorly. Optimal identification of the subset of patients who are at high risk of recurrence and would benefit from adjuvant treatment has been difficult. The purpose of this study was to evaluate the impact of somatic tumor mutation on survival outcomes in this patient population. For this study, low grade was defined as endometrioid FIGO grades 1 or 2, while early stage was defined as endometrioid stages I or II (disease confined to the uterus). Next-generation sequencing was performed using panels comprised of 46-200 genes. Recurrence-free and overall survival was compared across gene mutational status in both univariate and multivariate analyses. In all, 342 patients were identified, 245 of which had endometrioid histology. For grades 1-2, stages I-II endometrioid endometrial cancer patients, age (HR 1.07, 95% CI 1.03-1.10), CTNNB1 mutation (HR 5.97, 95% CI 2.69-13.21), and TP53 mutation (HR 4.07, 95% CI 1.57-10.54) were associated with worse recurrence-free survival on multivariate analysis. When considering endometrioid tumors of all grades and stages, CTNNB1 mutant tumors were associated with significantly higher rates of grades 1-2 disease, lower rates of deep myometrial invasion, and lower rates of lymphatic/vascular space invasion. When both TP53 and CTNNB1 mutations were considered, presence of either TP53 mutation or CTNNB1 mutation remained a statistically significant predictor of recurrence-free survival on multivariate analysis and was associated with a more precise confidence interval (HR 4.69, 95% CI 2.38-9.24). Thus, mutational analysis of a 2 gene panel of CTNNB1 and TP53 can help to identify a subset of low grade, early stage endometrial cancer patients who are at high risk of recurrence.

Genome-wide analysis of gynecologic cancer: The Cancer Genome Atlas in ovarian and endometrial cancer

Cancer typically develops due to genetic abnormalities, but a single gene abnormality cannot completely account for the onset of cancer. The Cancer Genome Atlas (CGA) project was conducted for the cross-sectional genome-wide analysis of numerous genetic abnormalities in various types of cancer. This approach has facilitated the identification of novel AT-rich interaction domain 1A gene mutations in ovarian clear cell carcinoma, frequent tumor protein 53 (TP53) gene mutations in high-grade ovarian serous carcinoma, and Kirsten rat sarcoma and B-rapidly accelerated fibrosarcoma proto-oncogene, serine/threonine kinase gene mutations in low-grade ovarian serous carcinoma. Genome-wide analysis of endometrial cancers has led to the establishment of four subgroups: Polymerase ultramutated, microsatellite instability hypermutated, genome copy-number low and genome copy-number high. These results may facilitate the improvement of the prediction of patient prognosis and therapeutic sensitivity in various types of gynecologic cancer. The enhanced use of currently available therapeutic agents and the development of novel drugs may be facilitated by the novel classification of ovarian cancer based on TP53 mutations, the efficacy of poly (ADP-ribose) polymerase inhibitors for tumors with breast cancer 1/2 mutations and the effect of phosphoinositide-3-kinase (PI3K)/mammalian target of rapamycin inhibitors for tumors with mutations in the PI3K/protein kinase B signaling pathway. Important results have been revealed by genome-wide analyses; however, the pathogenic underlying mechanisms of gynecologic cancer will require further studies and multilateral evaluation using epigenetic, transcriptomic and proteomic analyses, in addition to genomic analysis.

The significance of markers in the diagnosis of endometrial cancer

Endometrial cancer is one of the most common cancers experienced by women throughout the world. It is also the most common malignancy within the female reproductive system, representing 37.7% of all disorders. The incidence increases with age, and is diagnosed most frequently in women between 45 and 65 years old. In the last few years, numerous studies have been performed to identify tumour biomarkers. Biomarkers include not only protein routinely used as tumour markers but also genes and chromosomes. The limiting factor in the use of markers in the diagnosis of endometrial cancer is their lack of specificity. However, specific markers for endometrial cancer are the subject of much research attention. Although moderately elevated levels of markers are present in a number of inflammatory or non-malignant diseases, significantly increased levels of markers indicate the development of cancer. Recently, research has been focused on the identification of molecular changes leading to different histological subtypes of endometrial cancer. In this paper the authors reviewed several currently investigated markers. Progress in these investigations is very important in the diagnostics and treatment of endometrial cancer. In particular, the identification of novel mutations and molecular profiles should enhance our ability to personalise adjuvant treatment with genome-guided targeted therapy.

PTEN loss is a context-dependent outcome determinant in obese and non-obese endometrioid endometrial cancer patients

Endometrial cancer incidence is increasing, due in part to a strong association with obesity. Mutations in the phosphatidylinositol 3-kinase (PI3K) pathway, the central relay pathway of insulin signals, occur in the majority of endometrioid adenocarcinomas, the most common form of endometrial cancer. We sought to determine the impact of PI3K pathway alterations on progression free survival in a cohort of endometrioid endometrial cancers. Prognostic utility of PIK3CA, PIK3R1, and PTEN mutations, as well as PTEN protein loss by immunohistochemistry, was explored in the context of patient body mass index. Reverse-phase protein arrays were utilized to assess protein expression based on PTEN status. Among 187 endometrioid endometrial cancers, there were no statistically significant associations between PFS and PIK3CA, PIK3R1, PTEN mutation or loss. When stratified by body mass index, PTEN loss was associated with improved progression free survival (P < 0.006) in obese (body mass index ≥ 30) patients. PTEN loss resulted in distinct protein changes: Canonical PI3K pathway activation was observed only in the non-obese population while decreased expression of β-CATENIN and phosphorylated FOXO3A was observed in obese patients. These data suggest the impact of PTEN loss on tumor biology and clinical outcomes must be interpreted in the context of body mass index, and provide a potential explanation for discrepant reports on the effect of PTEN status and obesity on prognosis in endometrial cancer. This reveals a clinically important interaction between metabolic state and tumor genetics that may unveil the biologic underpinning of obesity-related cancers and impact ongoing clinical trials with PI3K pathway inhibitors.

PIpelle Prospective ENDOmetrial carcinoma (PIPENDO) study, pre-operative recognition of high risk endometrial carcinoma: a multicentre prospective cohort study

BACKGROUND

Endometrial carcinoma is the most common gynaecologic malignancy in industrialised countries and the incidence is still rising. Primary treatment is based on preoperative risk classification and consists in most cases of hysterectomy with bilateral salpingo-oophorectomy. In patients with serous and clear cell histology a complete surgical staging is mandatory. However, in routine clinical practice final histology regularly does not correspond with the preoperative histological diagnosis. This results in both over and under treatment.

METHODS/DESIGN

The aim of this multicentre, prospective cohort study is to select a panel of prognostic biomarkers to improve preoperative diagnosis of endometrial carcinoma in order to identify those patients that need extended surgery and/or additional treatment. Additionally, we will determine whether incorporation of cervical cytology and comorbidity could improve this preoperative risk classification. All patients treated for endometrial carcinoma in the participating hospitals from September 2011 till December 2013 are included. Patient characteristics, as well as comorbidity are registered. Patients without preoperative histology, history of hysterectomy and/or endometrial carcinoma or no surgical treatment including hysterectomy are excluded. The preoperative histology and final pathology will be reviewed and compared by expert pathologists. Additional immunohistochemical analysis of IMP3, p53, ER, PR, MLH1, PTEN, beta-catenin, p16, Ki-67, stathmin, ARID1A and L1CAM will be performed. Preoperative histology will be compared with the final pathology results. Follow-up will be at least 24 months to determine risk factors for recurrence and outcome.

DISCUSSION

This study is designed to improve surgical treatment of endometrial carcinoma patients. A total of 432 endometrial carcinoma patients were enrolled between 2011 and 2013. Follow-up will be completed in 2015. Preoperative histology will be evaluated systematically and background endometrium will be classified. This is the first study incorporating immunohistochemistry, cervical cytology and comorbidity to define the optimal panel of prognostic biomarkers that contribute in clinical decision making in the management of endometrial carcinoma.

TRIAL REGISTRATION

Netherlands Trial Register number NTR3503.

WWP2 and its association with PTEN in endometrial cancer

We wished to determine if WWP2 gene expression and PTEN protein levels inversely correlate in human endometrial cancer tissues. Fifty-one endometrioid endometrial tumors and five normal endometrial controls were available for analysis. PTEN protein levels were assessed by immunohistochemistry (IHC). WWP2 and PTEN gene expression were quantitated by RT PCR. Clinical and pathologic information was collected by chart review.

We found that in tumors with low PTEN protein but normal mRNA expression there were significantly higher levels of WWP2 expression (p = 0.0017). Increased WWP2 expression was not associated with clinical prognostic factors including lymphovascular space invasion, ≥ 50% myometrial invasion, grade, stage or recurrence. WWP2 expression was not different statistically between tumors and normal controls (p = NS). Therefore, in this cohort, tumors with low PTEN protein but normal mRNA expression had elevated levels of WWP2 expression. This suggests that WWP2 may be playing a role in PTEN degradation in endometrial cancer.

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WWP2 is a ubiquitin ligase shown to degrade PTEN in previous studies.

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We investigated WWP2 levels in endometrial cancers.

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WWP2 levels in tumors with normal gene expression but loss of PTEN protein on IHC were compared to tumors without PTEN protein loss on IHC.

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WWP2 levels were significantly higher in tumors with normal gene expression but loss of PTEN protein on IHC

Induction of human chronic myeloid leukemia K562 cell apoptosis by virosecurinine and its molecular mechanism

Virosecurinine is a major alkaloid of the plant Securinega suffruticosa and has been found to be a potent agent in inducing the differentiation of cancer cells. The present study aimed to investigate the antitumor effects of virosecurinine by inducing the apoptosis of leukemic K562 cells and to examine the underlying mechanisms. K562 cells were treated with different concentrations of virosecurinine (6.25, 12.5, 25, 50, 100 and 200 µmol/l) for 24, 48 and 72 h. The cell counting kit (CCK)‑8 method was used to detect the antitumor effect of K562 cells in vitro. Flow cytometry was used to observe the apoptotic ratio and analyze the cell cycle following treatment with virosecurinine in K562 cells. Light and electron microscopy was used to identify morphological alterations in the virosecurinine‑treated K562 cells. The mRNA levels of mammalian target of rapamycin (mTOR), SH2 domain‑containing inositol‑5'‑phosphatase 2 (SHIP2), phosphatase and tensin homologue (PTEN) and breakpoint cluster region (BCR)/Abelson (ABL) were detected pre and post‑virosecurinine treatment using reverse transcription quantitative polymerase chain reaction (RT‑qPCR). The generation depression effects of K562 cells cultured in vitro were detected using CCK‑8 technology, which revealed a dose and time‑dependent association. The IC50 was 32.984 µmol/l at 48 h. Flow cytometric analysis indicated that treatment with virosecurinine at concentrations of 6.25, 25 and 50 µmol/l increased the apoptotic rate of the K562 cells and caused G1/S phase arrest. RT‑qPCR indicated that virosecurinine upregulated the gene expression of PTEN and downregulated the expression of mTOR, SHIP‑2 and BCR/ABL in K562 cells. Virosecurinine inhibited the growth and proliferation of the K562 cell lines and induced apoptosis in K562 cells by affecting the expression of mTOR, SHIP2, BCR/ABL and PTEN.

Expression of PTEN in endometrial liquid-based cytology

OBJECTIVES

Endometrial cytology offers a reliable alternative to biopsy in endometrial cancer detection and it may be useful in obtaining material to study prognostic and predictive markers. Over the years, new sampling devices have been developed. Molecular alterations in endometrial cancers were previously described using formalin-fixed paraffin-embedded tissues with particular attention, in endometrioid carcinomas, to the PTEN-PI3K pathway. PTEN evaluation could be useful in endometrial carcinomas for selecting patients for target therapies.

STUDY DESIGN

We studied 51 endometrial samples collected using the Endogyn device and 71 obtained with the Endoflower dispositive device, and processed using liquid-based cytology. Most of the cases were matched with a corresponding histological biopsy. The overall accuracy of Endoflower was 100%. Immunohistochemistry (IHC) and immunocytochemistry (ICC) for PTEN were performed using monoclonal antibody 6H2.1 from DAKO.

RESULTS

The IHC showed PTEN-null glands in 4 cases. The same cancers were negative in ICC. Among the 10 carcinomas on cytology, PTEN-null glands were found in 1 case. All the normal endometrium control cases were positive in cytology and histology.

CONCLUSIONS

Our results suggest that endometrial devices provide useful material for the diagnosis and evaluation of PTEN expression.

HER-2/neu is an independent prognostic factor in type I endometrial adenocarcinoma

PURPOSE

To define the prognostic significance of HER-2/neu and PTEN expression in patients with endometrioid (type I) endometrial cancer.

METHODS

Seventy-seven patients with endometrioid endometrial carcinoma were included in the study, in a period between 1996 and 2009. Patients with coexisting malignancy and those having incomplete immunohistochemical data or clinical follow-up were excluded. Histological staging was defined according to the revised FIGO staging (2009). Clinico-pathologic and immunohistochemical characteristics were correlated in a multivariate Cox regression analysis with overall survival (OS), cancer-related survival (CRS) and disease-free survival (DFS).

RESULTS

Mean age of the patients was 62.7 years. The median follow-up was 67 months (9-124 months). HER-2/neu expression was detected in 18.2 % (n = 14), and PTEN expression in 72.7 % (n = 56) of our patients. Multivariate Cox regression analysis showed that patient's age, FIGO staging and HER-2/neu expression were independent prognostic factors for OS, CRS and DFS. PTEN expression did not significantly affect survival outcomes of the present study.

CONCLUSIONS

HER-2/neu but not PTEN expression is an independent prognostic factor for type I endometrial carcinoma.

Overexpression of cytoplasmic β-catenin inhibits the metastasis of the murine osteosarcoma cell line LM8

Background

Previously, we found that treatment of LM8 murine osteosarcoma cells with genistein, an isoflavone found in soy, increased the cellular level of β-catenin and decreased its invasive and motile potential. The purpose of this study is to investigate whether the expression of β-catenin in LM8 cells is associated with metastatic potential in nude mice. To this end, we used untreated and genistein-treated LM8 cells.

Methods

LM8 cells were treated for 3 days with or without 50 μM genistein and harvested by trypsinization. Untreated (the control group) and genistein-treated (the genistein group) cells were subcutaneously inoculated into the backs of male nude mice. After 25 days of inoculation, the tumors, lungs, and livers were excised, fixed in 10% formalin, and embedded in paraffin. The sections of formalin-fixed, paraffin-embedded lungs and livers were stained with hematoxylin-eosin (H&E) to confirm the absence or presence of metastatic tumors. The expression of β-catenin within the primary tumor was immunohistochemically examined.

Results

All mice in the control group (n = 8) exhibited large primary tumors, while in the genistein group (n = 8), one mouse showed no tumor formation and the remaining seven mice exhibited smaller primary tumors compared with the control group. The tumor mass of the genistein group was 23% of that of the control group. In the control group, multiple metastatic tumors were found in the lung and/or liver and the metastatic incidence was 100% in the lung and 87.5% in the liver. Six of seven tumor-bearing mice in the genistein group developed no metastatic tumors in the lung or liver, and this group was termed the genistein/metastasis(-) subgroup. Positive β-catenin immunostaining was observed in the cytoplasm of tumor cells, and the β-catenin-labeling index was higher in the genistein/metastasis(-) subgroup than in the control group. The intensity of cytoplasmic β-catenin immunostaining was stronger in the genistein/metastasis(-) subgroup compared with the control group, and the β-catenin-labeling score was 1.9-times higher in the former subgroup than in the latter group.

Conclusions

Overexpression of cytoplasmic β-catenin in LM8 cells causes inhibition of the growth of primary tumors and loss of the metastatic potential to the lung and liver.

The expression of PTEN is associated with improved prognosis in patients with ampullary adenocarcinoma after pancreaticoduodenectomy

CONTEXT

Phosphatase and tensin homolog (PTEN) is one of the most frequently inactivated tumor suppressor genes in sporadic cancers. Somatic mutations of PTEN occur in many tumors including those of the gastrointestinal and hepatobiliary tracts. Loss of PTEN expression is associated with poor prognosis in patients with metastatic colonic adenocarcinoma, gastroesophageal junction adenocarcinoma, gastric adenocarcinoma, and pancreatic ductal adenocarcinoma.

OBJECTIVE

To study the expression of PTEN and its significance in ampullary adenocarcinoma (AA).

DESIGN

We constructed tissue microarrays by using archival tissue from 92 patients (55 males, 37 females; median age, 63 years; age range, 37 to 87 years) with previously untreated AA who underwent pancreaticoduodenectomy at our institution. PTEN expression was evaluated by immunohistochemistry, scored semiquantitatively (based on staining intensity and percentage positive tumor cells), and correlated with clinicopathologic features and survival.

RESULTS

Of 92 cases, 23 (25.0%) were PTEN negative. Loss of PTEN expression correlated with lymph node metastasis (P = .004), advanced American Joint Committee on Cancer (AJCC) stage (P = .02), and higher frequency of recurrence (P = .03). Patients with PTEN-negative tumors had shorter disease-free survival (DFS, mean: 89.0 ± 20.8 months) and overall survival (OS, mean: 93.1 ± 19.1 months) than those with PTEN-positive tumors (DFS, mean: 161.4 ± 11.7 months, P = .01; OS, mean: 175.4 ± 11.0 months, P = .001). In multivariate analyses, PTEN expression was a prognostic factor for both DFS and OS, independent of AJCC stage, lymph node status, pathologic tumor (pT) stage, and differentiation.

CONCLUSIONS

Loss of PTEN expression is associated with poor DFS and OS in patients with AA after curative surgery. PTEN expression may be used as a prognostic marker for patients with resected AA.

Expression of p53 in imprint smears of endometrial carcinoma

The aims of this study were to determine the expression of p53 protein in endometrial adenocarcinomas (as a potential prognostic indicator before treatment) as well as normal endometrium in imprint smears and to correlate the results with clinicopathologic parameters of primary untreated endometrial cancer patients. Two hundred fifty five patients were evaluated with endometrial imprint cytology during a 29-month period. Endometrial samples freshly resected from women who underwent total abdominal hysterectomy were studied. One hundred twenty six patients had endometrial carcinoma and 129 cases were diagnosed as normal endometrium. The expression of p53 was assessed by immunocytochemistry. Positive staining was correlated with increased surgical-pathological stage, histological grade and lymph node metastases. High expression of p53 staining was significantly more frequent in histological type II than type I endometrial adenocarcinoma. High-grade endometrial carcinoma had higher proportions and stronger intensity compared with low-grade carcinoma. Negative immunostain for p53 protein was found in proliferative, secretory, and atrophic endometrium. Immunocytochemical findings from p53 stain, in addition to cytomorphologic features, appeared to be useful in the diagnosis and in the postoperative prognosis of endometrial carcinoma in endometrial cytology, especially if combined with other markers. High p53 expression correlates with morphologic features of aggressiveness and the expression pattern of p53 correspond to the expected cyclic/atrophic pattern in normal endometrium.

Characterization of disease progression in ovarian cancer by utilizing 'chemograms' of ovarian cancer stem cells

INTRODUCTION

Ovarian cancer is one of the leading causes of death in women with cancer. First-line chemotherapy with platinum compounds and taxane compounds has been effective, but most patients develop a relapse of the disease due to drug resistance. There is growing evidence that this resistance may be due to the presence of ovarian cancer stem cells.

DISCUSSION

Cells with properties of cancer stem cells have been isolated from the ascitic fluid of ovarian cancer patients. This subset of cells is highly tumourigenic compared to the rest of the cells in the ascitic fluid. They are known to exude harmful chemicals from their cytoplasm and have been found to be resistant to chemotherapeutic agents. This property has been utilized to purify them by fluorescence assisted cytometry to yield a subset of cells which are called 'side population'. These cells exhibit the properties of cancer stem cells and their role in disease progression is being currently investigated. The course of the disease can be potentially characterized at the cellular level by closely studying this cell population. They can also be cultured in different combinations of chemotherapeutic agents at varying concentrations to obtain 'chemograms' which are sensitivity charts. Chemotherapeutic agents which produce the most effective kill curves can then be rationally used as a second-line chemotherapy if the disease relapses. These sensitivity charts can provide insight into emerging patterns of chemoresistance and also help discover surface markers that accurately identify ovarian cancer stem cells.

CONCLUSION

The high rate of disease relapse in patients with ovarian cancer requires a new and different approach utilizing the sensitivity of cancer stem cells. Isolating and characterizing the resistance patterns of ovarian cancer stem cells may provide a rational approach towards an effective and individualized chemotherapeutic regimen.

Utility of Ki-67, p53, Bcl-2, and Cox-2 biomarkers for low-grade endometrial cancer and disordered proliferative/benign hyperplastic endometrium by imprint cytology

In this report, the authors examined the characteristic features of morphology and molecular biology of Ki-67, p53, Bcl-2, and cyclooxygenase-2 (Cox-2) immunocytochemistry in low-grade endometrioid endometrial carcinoma (LG-ENEC) and disordered proliferative (DP)/benign hyperplastic (BH) endometrium. We carried out a prospective study by collecting endometrial imprints from freshly resected uteri over a 20-month period and finally 104 patients were evaluated with endometrial cytology. We focused on LG-ENECs, as well as on BH endometrium and its precursor lesion, DP endometrium, firstly because of the overlapping cytomorphology of these pathologic entities and secondly because of the lack of agreement in the differential diagnosis of atypical hyperplasia from complex hyperplasia and well-differentiated endometrial carcinoma, even in curettage specimens. Ki-67 expression of LG-ENEC showed predominance in comparison with DP/BH endometrium. Furthermore, high levels of Bcl-2 (>50%) were expressed only in DP/BH endometrium. DP/BH endometrium was negative for p53 marker, except from two cases of BH endometrium. Cox-2 expression ≥50% was found only in LG-ENECs. Using Ki-67, Bcl-2, p53, and Cox-2 markers, we managed to distinguish fully DP/BH endometrium from LG-ENEC. Higher Ki-67%/Bcl-2% rate and also higher Cox-2 expression were found in LG-ENEC cases with FIGO stage ≥ IC, than in cases with FIGO stage < IC. The immunocytochemical findings from a combination of Ki-67, p53, Bcl-2, and Cox-2, may differentiate LG-ENEC from DP/BH endometrium with overlapping cytomorphology. Immunocytochemistry appeared to be useful also for the correlation between LG-ENEC and FIGO stage.

Molecular characterization of endometrial cancer: a correlative study assessing microsatellite instability, MLH1 hypermethylation, DNA mismatch repair protein expression, and PTEN, PIK3CA, KRAS, and BRAF mutation analysis

Endometrial cancer is associated with numeric and structural chromosomal abnormalities, microsatellite instability (MSI), and alterations that activate oncogenes and inactivate tumor suppressor genes. The aim of this study was to characterize a set of endometrial cancers using multiple molecular genetic and immunohistochemical techniques. Ninety-six cases were examined for genomic alterations by MSI, MLH1 promoter hypermethylation, p53 and mismatch repair protein expression (MLH1, MSH2, MSH6, PMS2), and PTEN, PIK3CA, KRAS, and BRAF mutation analysis. At least 1 alteration was identified in 48 of 87 (55%) specimens tested for PTEN, making it the most common abnormality in this study. A PIK3CA alteration was observed in 16 (17%) specimens. Twenty-nine of 94 (31%) MSI tested tumors exhibited an MSI-H phenotype. Of the 29 MSI-H cases, 24 (83%) were positive for methylation of the MLH1 promoter region. Twenty-three (82%) of the 28 MSI-H cases with immunohistochemistry results showed loss of expression of MLH1/PMS2 (n=19), MSH2/MSH6 (n=2), or MSH6 only (n=2). Of the 19 MSI-H cases with loss of MLH1/PMS2 on immunohistochemistry, 18 were positive, and 1 was equivocal for MLH1 promoter hypermethylation. Twelve of 94 cases (13%) analyzed for KRAS mutations were found to have a mutation. No BRAF V600E mutations were indentified. This study provides a comprehensive molecular genetic analysis of commonly analyzed targets in a large cohort of endometrial cancers.

Association of mammalian target of rapamycin with aggressive type II endometrial carcinomas and poor outcome: a potential target treatment

The classification of endometrial carcinoma divided into types I and II has shown clinical usefulness. Molecular alterations of PTEN and Wnt/β-catenin have been identified in this neoplasia. However, the role of mammalian target of rapamycin according to subcellular localization in the pathogenesis of this neoplasia and its prognostic significance are not well defined. We studied the expression of phosphorylated mammalian target of rapamycin, PTEN, and β-catenin and their relationship with clinicopathologic features, molecular factors (microsatellite instability, mismatch repair, and BRAF genes) and patients' survival in a series of 260 nonconsecutive endometrial carcinomas. Tissue microarrays were manually constructed, and genomic DNA was extracted from paraffin-embedded cylinders (1 mm thick) from preselected tumor areas. The mammalian target of rapamycin in the nuclei (mTORC2; 47%) or cytoplasm (mTORC1; 48%) were seen in type II endometrial carcinoma, the latter also in advanced stages (P ≤ .046). PTEN loss (58%) was detected in type I endometrial carcinoma of grade 1, at early stage, with mismatch repair gene loss (24.4%) and microsatellite instability-positive status (22%; P ≤ .05). Nuclear β-catenin (16%) was found in type I tumors of younger patients (P ≤ .003). In contrast, BRAF-V600E mutations were not detected (0%). Mammalian target of rapamycin cytoplasmic high expression implied poorer prognosis (P = .02; Kaplan-Meier, log-rank test), but grade 3 tumors, vascular invasion, advanced stage, or PTEN presence correlated independently with a negative impact on survival (all P ≤ .036; Cox analysis). Our results show that mammalian target of rapamycin, PTEN, and β-catenin are independently involved in different molecular subtypes of endometrial carcinoma with diverse patients' prognosis and support their distinctive treatment based on targeted drugs.

Predicting the Coexistence of an Endometrial Adenocarcinoma in the Presence of Atypical Complex Hyperplasia: Immunohistochemical Analysis of Endometrial Samples

Objective

This study aimed to determine whether immunohistochemical markers in complex atypical endometrial hyperplasia could predict the presence of a concurrent endometrial carcinoma.

Methods

Endometrial biopsies of 39 patients with complex atypical hyperplasia were selected retrospectively between 1999 and 2006. Only patients who underwent a hysterectomy were included. A coexisting endometrial carcinoma was present in 25 patients (64%). Immunohistochemical analysis was performed on formalin-fixed paraffin-embedded sections of the endometrial biopsies, using antibodies for MIB-1, β-catenin, E-cadherin, p53, PTEN, CD44, HER2-neu, survivin, COX-2, tenascin, and bcl-2. To evaluate the potential utility of these markers, a prediction model was constructed.

Results

In the univariate analysis, expressions of both PTEN and HER2-neu were significantly different between the groups with and without a coexisting endometrial carcinoma (P < 0.05). Loss of PTEN staining was found in 13 (54%) and 1 (7%) of the patients with and without a coexistent carcinoma, respectively (odds ratio, 16.55; 95% confidence interval [CI], 1.87–146.65). HER2-neu expression was found in only 2 (8.6%) and 6 (43%) patients with and without a coexistent carcinoma, respectively, and was excluded from further analysis because of its low expression. A prediction model containing PTEN expression only showed an area under the curve of 73.4% (95% CI, 57.3%–89.6%). After adding MIB-1 and p53, discriminative power improved to 87.2% (95% CI, 75.1%–99.3%).

Conclusions

This study showed that PTEN expression in complex endometrial hyperplasia is a promising factor for the prediction of the presence of a coexisting endometrial carcinoma, and prediction may even better when MIB-1 and p53 expressions are considered simultaneously.

Strategies for distinguishing low-grade endometrioid and serous carcinomas of endometrium

Distinction between endometrioid and serous carcinomas of the endometrium has important prognostic and therapeutic implications. Misdiagnosing a serous carcinoma as endometrioid can have significant consequences for the patient and pathologist. Although many cases are straightforward and easy to classify, there are occasional problematic cases. This review focuses on strategies that help differentiate between low-grade endometrioid carcinoma and serous carcinoma of the endometrium. We will discuss clinical, morphologic, and immunohistochemical differences between the 2 entities and provide practical tips for practicing pathologists when confronted with this differential diagnosis.

Activation of the phosphatidylinositol 3'-kinase/AKT pathway in neuroblastoma and its regulation by thioredoxin 1

Neuroblastoma is a malignant pediatric tumor with poor survival. The phosphatidylinositol 3'-kinase/AKT pathway is a crucial regulator of cellular processes including apoptosis. Thioredoxin 1, an inhibitor of tumor-suppressor phosphatase and tensin homolog, is overexpressed in many tumors. The objective of this study was to explore phosphatidylinositol 3'-kinase/AKT pathway activation and regulation by thioredoxin 1 to identify potential therapeutic targets. Immunohistochemical analysis was done on tissue microarrays from tumor samples of 101 patients, using antibodies against phosphatidylinositol 3'-kinase, AKT, activated AKT, phosphatase and tensin homolog, phosphorylated phosphatase and tensin homolog, thioredoxin 1, epidermal growth factor receptor, vascular endothelial growth factor and receptors (vascular endothelial growth factor 1 and vascular endothelial growth receptor 2), platelet-derived growth factor receptors, insulin-like growth factor 1 receptor, neurotrophic tyrosine kinase receptor type 2, phosphorylated 70-kd S6 protein kinase, 4E-binding protein 1, and phosphorylated mammalian target of rapamycin. Using 3 neuroblastoma cell lines, we investigated cell viability with AKT-specific inhibitors (LY294002, RAD001) and thioredoxin 1 alone or in combination. We found activated AKT and AKT expressed in 97% and 98%, respectively, of neuroblastomas, despite a high expression of phosphatase and tensin homolog correlated with thioredoxin 1. AKT expression was greater in metastatic than primary tumors. Insulin-like growth factor 1 receptor, tyrosine kinase receptor type 2, vascular endothelial growth receptor 1, and downstream phosphorylated 70-kd S6 protein kinase were correlated with activated AKT. LY294002 and RAD001 significantly reduced AKT activity and cell viability and induced a G(1) cell cycle arrest. Thioredoxin 1 decreased cytotoxicity of AKT inhibitors and doxorubicin, up-regulated AKT activation, and induced cell growth. Thus, vascular endothelial growth receptor 1, tyrosine kinase receptor type 2, insulin-like growth factor 1 receptor, and thioredoxin 1 emerged as preferentially committed to phosphatidylinositol 3'-kinase/AKT pathway activation as observed in neuroblastoma. Thioredoxin 1 is a potential target for therapeutic intervention.

Biomarkers and microsatellite instability analysis of curettings can predict the behavior of FIGO stage I endometrial endometrioid adenocarcinoma

The prognostic value of molecular biomarkers, microsatellite instability, DNA ploidy and morphometric mean shortest nuclear axis in endometrial cancer is conflicting, possibly due to the fact that different studies have used mixtures of histotypes, FIGO stages and different non-standardized non-automated methods. We have evaluated the prognostic value of classical prognostic factors, molecular biomarkers, microsatellite instability, DNA ploidy and morphometric mean shortest nuclear axis in a population-based cohort of FIGO stage I endometrial endometrioid adenocarcinomas. Curettings of 224 FIGO stage I endometrial endometrioid adenocarcinoma patients were reviewed. Clinical information, including follow-up, was obtained from the patients' charts. Microsatellite instability and morphometric mean shortest nuclear axis were obtained in whole tissue sections and molecular biomarkers using tissue microarrays. DNA ploidy was analyzed by image cytometry. Univariate (Kaplan-Meier method) and multivariate (Cox model) survival analysis was performed. With median follow-up of 66 months (1-209), 14 (6%) patients developed metastases. Age, microsatellite instability, molecular biomarkers (p16, p21, p27, p53 and survivin) and morphometric mean shortest nuclear axis had prognostic value. With multivariate analysis, combined survivin, p21 and microsatellite instability overshadowed all other variables. Patients in which any of these features had favorable values had an excellent prognosis, in contrast to those with either high survivin or low p21 (97 vs 78% survival, P<0.0001, hazard ratio=7.8). Combined high survivin and low p21 values and microsatellite instability high identified a small subgroup with an especially poor prognosis (survival rate 57%, P=0.01, hazard ratio=5.6). We conclude that low p21 and high survivin expression are poor prognosis indicators in FIGO stage I endometrial endometrioid adenocarcinoma, especially when high microsatellite instability occurs.

Cadherins, catenins and cell cycle regulators: impact on survival in a Gynecologic Oncology Group phase II endometrial cancer trial

OBJECTIVE

We evaluated the clinical relevance of catenins, cadherins and cell cycle regulators in stage IV or recurrent endometrial carcinoma in a multi-center phase II trial (GOG protocol #119).

METHODS

Tissue microarrays of metastatic or recurrent (n=42) tumor were developed and immunohistochemistry was performed. Average expression (percent staining x intensity) was assessed in tumor epithelium ((E)) and stroma ((S)) and categorized into tertiles (T1, T2, T3) for E-cadherin(E), N-cadherin(E), alpha-catenin(E), beta-catenin(E), gamma-catenin(E), p120-catenin(E) and Ki-67(E); as negative, below median or above median for p16(E), p27(E) and CD44(S); or as negative or positive for p53(E), Ki-67(S) and APC(S) (adenomatous polyposis coli). End points included response and survival.

RESULTS

E-cadherin(E), p16(E), and p53(E) varied by race (p=0.003, p=0.024, p=0.002,) and N-cadherin(E), Ki-67(E), p16(E) and p27(E) by tumor type (p=0.015, p=0.011, p=0.005, p=0.021). Correlations were observed among E-cadherin(E) with p120(E) (r=0.66), p53(E) (r=-0.32), alpha-catenin(E) (r=0.52), beta-catenin(E) (r=0.58), and gamma-catenin(E) (r=0.58). High E-cadherin(E) (T2 or T3) versus low (T1) expression was associated with better survival in unadjusted (hazard ratio [HR]=0.14, 95% confidence interval [CI]=0.06-0.37 or HR=0.17, 95% CI=0.07-0.42) and adjusted models (HR=0.18, 95% CI=0.05-0.59 or HR=0.22, 95% CI=0.07-0.70). High p16(E) versus negative expression was associated with worse survival in unadjusted (HR=3.87, 95% CI=1.74-8.61) and adjusted (HR=4.18, 95% CI=1.28-13.6) models. Positive versus negative expression of p53(E) was associated with worse survival in unadjusted (HR=2.31, 95% CI=1.16-4.60) but not adjusted models.

CONCLUSIONS

E-cadherin(E) and p16(E) appear to be clinically relevant, independent prognostic factors in stage IV or recurrent endometrial cancers treated with Tamoxifen and Medroxyprogesterone acetate, and merit further study.

Evaluation of apoptosis in cytologic specimens

A hallmark of neoplasia is dysregulated apoptosis, programmed cell death. Apoptosis is crucial for normal tissue homeostasis. Dysregulation of apoptotic pathways leads to reduced cytocidal responses to chemotherapeutic drugs or radiation and is a frequent contributor to therapeutic resistance in cancer. The literature pertaining to detection of apoptotic pathway constituents in cytologic specimens is reviewed herein. Virtually all methods for detecting apoptosis, including classic cytomorphologic evaluation, TUNEL assay, immunocytochemistry, and gene sequence analysis, may be applied to cytologic samples as well as tissue. Components of both intrinsic and extrinsic apoptotic pathways have been studied, including many reports examining p53 and bcl-2, as well as studies of caspase inhibitory proteins XIAP and survivin, death receptors and ligands such as Fas, Fas-ligand, and TRAIL. p53 undergoes oncogenic alteration more than any other protein; its immunocytochemical detection almost always connotes loss of its physiologic role as an inducer of apoptosis in response to a damaged genome. Several reports establish cytologic sampling as being as useful as tissue sampling. In one respect cytologic sampling is superior to tissue sampling in particular, by allowing clinicians to repeat sampling of the same tumor before and after administration of therapy; a number of reports use this approach to attempt to predict tumor response by assaying the effect of chemotherapy on the induction of apoptosis.

Prognostic value of microsatellite instability (MSI) and PTEN expression in women with endometrial cancer: results from studies of the NCIC Clinical Trials Group (NCIC CTG)

AIM

The impact of PTEN status and microsatellite instability (MSI) on the prognosis of women with endometrial cancer is controversial. The aim of this study was to investigate MSI and PTEN expression in two patient populations using data from NCIC CTG studies.

METHODS

Archival paraffin embedded tumour from women with endometrial cancer enrolled in NCIC CTG studies: EN5 (stage I/II) and IND 126, 148 and 160 (advanced/recurrent disease) were examined for MSI using BAT25/26 and for PTEN expression using immunohistochemistry. PTEN and MSI status were correlated with clinicopathologic variables and survival using data from NCIC CTG trial databases.

RESULTS

PTEN and MSI results were available from 128 and 163 patients, respectively. MSI+ tumours were more common in women enrolled in EN5 compared to the IND studies (p=0.01). PTEN negative tumours were associated with improved survival in both univariate (hazard ratio (HR) 0.55, 95% confidence interval (CI) 0.32-0.94; p=0.03) and multivariate (adjusted HR 0.54, 95% CI 0.30-0.96; p=0.03) analyses in women enrolled in IND studies. Microsatellite stable tumours were associated with an improved prognosis in univariate (HR 0.18, 95% CI 0.06-0.51; p<0.0001) and multivariate (adjusted HR 0.16, 95% CI 0.05-0.5; p<0.0001) analyses in women enrolled in EN5. There was no significant correlation between MSI and PTEN status.

CONCLUSIONS

PTEN negative tumours in women with advanced disease are associated with improved survival. MSI+ tumours are more common in early stage disease and in this group of women are associated with a worse prognosis.

p53 overexpression in morphologically ambiguous endometrial carcinomas correlates with adverse clinical outcomes

The distinction between uterine serous and endometrioid carcinomas can usually be achieved by morphologic examination alone. However, there are occasional 'morphologically ambiguous endometrial carcinomas' that show overlapping serous and endometrioid features and defy histologic classification. The primary aim of this study was to assess the clinical significance of p53 overexpression using immunohistochemistry in such tumors. Related aims included (1) assessing interobserver diagnostic concordance for histologic subclassification of these tumors using a panel of pathologists with and without gynecologic pathology expertise and (2) elucidating the histologic features that correlate with p53 status. Thirty-five such cases were identified during the study period. p53 overexpression was seen in 17 of 35 cases. Tumors with p53 overexpression were associated with a significantly inferior progression-free survival and disease-specific survival compared with those that lacked p53 overexpression (3-year progression-free survival and disease-specific survival were 94 and 100% in patients with no p53 overexpression, and 52 and 54% in patients with p53 overexpression; P=0.02 and 0.003, respectively). The consensus diagnosis rendered by gynecologic pathologists was predictive of disease-specific survival (P=0.002), but not progression-free survival (P=0.11). Although the interobserver diagnostic concordance (kappa=0.70) was substantial for gynecologic pathologists, and highly associated with p53 status (77% of 'favor serous' cases showed p53 overexpression, whereas only 25% of 'favor endometrioid' cases showed p53 overexpression; P=0.005), the concordance between the consensus diagnosis of the two specialized pathologists versus each of three non-specialized pathologists was poor (kappa=0.13-0.25). The histologic feature that correlated most with p53 overexpression was the presence of diffuse high nuclear grade. p53 immunohistochemistry assays in morphologically ambiguous endometrial carcinomas are roughly as clinically informative as gynecologic pathology consultation and can be helpful for prognostic assessment and therapeutic decision making in difficult endometrial carcinomas.

Altered PTEN expression; a diagnostic marker for differentiating normal, hyperplastic and neoplastic endometrium

Background

Different molecular alterations have been described in endometrioid endometrial carcinoma (EECA). Among them the most frequently altered is loss of the PTEN protein, a tumor suppressor gene. The purpose of this study was to evaluate the expression pattern of PTEN gene in normal, hyperplastic and neoplastic endometrium.

Methods

In a study in a referral gynecologic hospital in Tehran, Iran, immunohistochemical (IHC) evaluation of PTEN was performed on 87 consecutive specimens to the following three groups; group A- normal proliferative endometrium(n = 29); group B- hyperplastic endometrium [including simple hyperplasia without atypia(n = 21) and complex hyperplasia with atypia (n = 8)] and group C- EECA(n = 29). Immunostaining of cells was analyzed by arbitrary quantitative methods according to both slide's area staining and intensity of color reaction.

Results

PTEN immunoreactivity was present in all normal proliferative endometrium, all simple hyperplasia, 75% of atypical complex hyperplasia and in 48% of EECA (P < 0.001). The intensity of PTEN reaction was significantly higher in group with proliferative endometrium than hyperplastic endometrium and EECA (P < 0.001).

Conclusion

PTEN expression was significantly higher in cyclical endometrium than in atypical hyperplasia and endometrioid carcinoma.

Utility of PTEN expression of endometrial "surface epithelial changes" and underlying atypical endometrial hyperplasia

Surface epithelial changes (SECs) have been reported to be associated with endometrial carcinoma in about 49% of cases. They have also been seen to be associated with endometrial hyperplasia. Although morphologically benign, these lesions are considered a marker for underlying malignancy. Their true biologic nature, however, is not known. PTEN has been reported to be altered in endometrial carcinomas and endometrial precancers where no morphologic changes are appreciated. The current study aims to investigate PTEN status in the endometrial SECs. Thirty-two cases of endometrial biopsy are divided into 2 groups: group 1 had 18 cases of SEC and underlying endometrial atypical hyperplasia and group 2 had 14 cases of SEC alone. Four-micron sections were cut from each block and stained with antibodies to PTEN. One section was stained with hematoxylin and eosin to confirm the presence of the area of interest. Positive and negative control slides were run with each batch of staining. All 32 cases were followed for a median period of 54 (range, 21 to 84) months. Overall, PTEN alteration (NULL) was found in 12 of the 32 cases of endometrial samples (37.5%) examined. In group 1, 10 of the 18 cases (56%) of atypical endometrial hyperplasia with "SECs" showed PTEN NULL. Of these 10 cases, 6 (60%) cases showed FIGO grade 1 endometrioid carcinoma in subsequent hysterectomy specimens. Two other cases (20%) had atypical endometrial hyperplasia only. In group 2, two of the 14 (14%) cases of SECs alone showed PTEN NULL phenotype. These 2 patients were followed for 26 and 63 months, respectively, and subsequent endometrial biopsies and pap smears were negative. Of the remaining 12 cases that retained PTEN, 9 cases (75%) were negative when followed for a median of 54 months (range, 21 to 84 mo). SECs seem to be a heterogeneous entity. Presence of PTEN NULL phenotype in SECs and associated endometrial hyperplasia does not necessarily predict an increased incidence of endometrioid carcinoma in subsequent follow-up. However, absence of PTEN NULL phenotype in SECs alone may predict a benign follow-up.

Should Preoperative Pathology Be Used to Select Patients for Surgical Staging in Endometrial Cancer?

Introduction:

The decision to offer surgical staging in endometrial cancer is often based on preoperative histology and grade from endometrial biopsy or dilatation and curettage. The primary objective of this study was to evaluate the concordance between preoperative and final pathology from a population-based study of endometrial cancer to address whether preoperative biopsy is a reliable determinant in selecting patients for surgical staging.

Methods:

Retrospective cohort study in Ontario, Canada, from 1996 to 2000. The study included all women with a preoperative diagnosis of endometrioid adenocarcinoma on endometrial biopsy or dilatation and curettage, followed by definitive surgery. All other histological types were excluded. Surgical staging rates were compared according to preoperative pathology. Primary outcome measure was the concordance between preoperative and final pathology, expressed as a Spearman correlation coefficient (ρ). A multivariable logistic regression estimated the effects of demographic variables and grade on our outcome measure.

Results:

There were 1804 evaluable cases in this study. For preoperative grades 1, 2, and 3 endometrioid adenocarcinoma, surgical staging rates were 9.1%, 13.7%, and 25.6%, respectively. Concordance rates with final pathology were 73%, 52%, and 53%, respectively. There was only moderate concordance between preoperative and final pathology (ρ = 0.52). There was no significant difference in concordance rates according to age, year, or hospital volume, but lower concordance rates among teaching hospitals.

Conclusion:

Preoperative biopsy has only a moderate ability to predict final pathology in endometrial cancer, and therefore, additional factors should be considered in selecting patients for a surgical staging procedure.

Proteomics and cancer epidemiology

Profiling of differentially expressed proteins is perhaps the most important and useful approach in developing tools for risk assessment in a population, diagnostic screening, and therapeutics. Proteomic markers have potential for identifying individuals at high risk of developing cancer; however, these markers have not been extensively used in cancer epidemiologic studies. Several markers have to be clinically validated. In this chapter, methods used in proteomic analysis of clinical samples, challenges in the proteomics and cancer epidemiology, and their potential solutions are discussed.

Junctional Adhesion Molecule: An Expression in Human Endometrial Carcinoma

Junctional adhesion molecule A (JAM-A) is involved in cell-cell contact and tight junction formation. Loss of cell adhesion molecules may be associated with high histologic grade and invasiveness of endometrial carcinoma. We attempted to determine JAM-A expression in human endometrial carcinoma and its correlations with pathologic features, stage, and survival. Junctional adhesion molecule A expression in human endometrial carcinoma was evaluated by immunohistochemistry. In addition, we cultured human well and poorly differentiated endometrial adenocarcinoma cell lines, Ishikawa cells, and KLE in 3-dimensional basement membrane preparation, and JAM-A expression in these cells was assessed by real-time reverse transcription-polymerase chain reaction and immunohistochemistry. Junctional adhesion molecule A immunostaining intensity was negatively correlated with histologic grade (τ = −0.420, P < 0.0001), myometrial invasion (τ = −0.306, P < 0.01), and stage (τ = −0.383, P < 0.0001). Low JAM-A immunostaining intensity was associated with positive vascular space involvement (P < 0.01). Moreover, low immunostain intensity was significantly (P < 0.0001) related to low overall survival rate and progression-free survival rate. Additionally, in our 3-dimensional epithelial cell culture, JAM-A expression in poorly differentiated adenocarcinoma was significantly lower than that in well-differentiated adenocarcinoma (P < 0.001). Junctional adhesion molecule A expression seems to be reduced in high-grade or advanced endometrial carcinoma and may be a prognostic factor.

Prognostic factors in endometrial carcinoma

Endometrial carcinoma is the most common malignancy of the female genital tract in industrialized countries, and occurs predominantly after the menopause. Although most endometrial carcinomas are detected at low stage, there is still a significant mortality from the disease. In postmenopausal women, prolonged life expectancy, changes in reproductive behavior and prevalence of overweight and obesity, as well as hormone replacement therapy use, may partially account for the observed increases of incidence rates in some countries. In order to improve treatment and follow-up of endometrial carcinoma patients, the importance of various prognostic factors has been extensively studied. The identification of high-risk groups would make it possible to avoid unnecessary adjuvant treatment among patients with a good prognosis. Over the past few decades, several studies have demonstrated the prognostic importance of different parameters including lymph node status, histological type of carcinoma (serous carcinoma and clear cell carcinomas are poor prognostic types), histological grade, stage of disease, depth of myometrial invasion, lymphovascular space involvement and cervical involvement. Other factors currently being investigated are estrogen and progesterone receptor status, p53 status, flow cytometric analysis for ploidy and S-phase fraction, and oncogenes such as HER-2/neu (c-erbB-2).

PTEN and rapamycin inhibiting the growth of K562 cells through regulating mTOR signaling pathway

OBJECTIVE

To investigate, in vitro, the regulatory effects of tumor-suppressing gene PTEN on mTOR (mammalian target of rapamycin) signaling pathway, the effects of transfected PTEN and rapamycin on the growth inhibition, and apoptosis induction for human leukemia cell line K562 cells.

METHODS

K562 cells were transfected with recombined adenovirus-PTEN vector containing green fluorescent protein (Ad-PTEN-GFP), followed by the treatment of the cells with or without rapamycin. The proliferation inhibition rate and apoptotic rate of these transfected and/or rapamycin treated K562 cells were measured by MTT assay and flow cytometry (FCM), the expression levels of PTEN-, mTOR-, cyclinD1- and P27kip1- mRNA were measured by real-time fluorescent relative-quantification reverse transcriptional PCR (FQ-PCR), the protein expression levels of PTEN, Akt, p-Akt were detected by western blotting.

RESULTS

The proliferation of K562 cells was inhibited by PTEN gene transfection with/without the treatment of rapamycin. The expression levels of PTEN- and P27kip1- mRNA were up-regulated, and the mTOR- and cyclinD1- mRNA were down-regulated in K562 cells after the cells transfected with wild type PTEN gene and treated with rapamycin.

CONCLUSION

PTEN and rapamycin inhibited mTOR expression by acting as an upstream regulator of mTOR. Low dose rapamycin in combination with over-expressed PTEN might have synergistic effects on inhibiting the proliferation and promoting apoptosis of K562 cells.

PI3 kinase/AKT pathway as a therapeutic target in multiple myeloma

The development of novel therapies for multiple myeloma depends on a comprehensive understanding of the events leading to cellular proliferation and survival. Controlling pathways that regulate growth signals is an emerging and complementary approach to myeloma treatment. The PI3K/Akt pathway is a central gatekeeper for crucial cellular functions including adhesion, angiogenesis, migration and development of drug resistance. Established proteins and genes such as mTOR, p53, NF-kappaB and BAD are all regulated through PI3K and Akt activation, making them attractive targets for broad downstream effects. Direct PI3K inhibition has demonstrated impressive tumor inhibition and regression in cell-line and animal models, and multiple agents including SF1126 are currently in clinical trials. Drugs such as perifosine that are specific for Akt are also in development. Combinations of these agents with existing therapies are rational approaches on the path to improving myeloma treatment.