Search

Cancer stem cells (CSCs) possess the ability for self-renewal, differentiation, and tumorigenesis and play a role in cancer recurrence and metastasis. CSCs are usually sorted in analysis into side population (SP) cells using ultraviolet (UV) laser (350 nm) excitation; they cannot be stained with Hoechst 33342 because of their efflux ability. However, it is difficult to avoid cell damage using a UV laser. Therefore, we attempted to isolate CSCs using a violet laser (407 nm) excitation to avoid cellular DNA damage. We sorted SP cells and main population (MP) cells from a human endometrial cancer cell line using the FACSAria system equipped with a violet laser and analyzed the biological properties of these cells. SP cells exhibited drug efflux, self-renewal, differentiation abilities, and tumorigenicity. It was found that v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS) expression was significantly higher in SP cells than in MP cells. Our results suggest that CSCs exist in the SP fraction sorted using the FACSAria system equipped with a violet laser, which presents a useful tool to isolate small populations of viable putative CSCs from solid tumors and can be used to identify and characterize CSCs.

Endometrial cancer is one of the most common gynecological malignancies in Japan, where the disease shows an increasing morbidity. However, surgical therapy remains the treatment of choice for endometrial cancers that tend to be insensitive to radiation therapy and chemotherapy. Therefore, novel therapeutic strategies are required. The Notch signaling pathway regulates embryogenesis and cellular development, but deregulated Notch signaling may contribute to tumorigenesis in several cancers. Moreover, γ-secretase inhibitors have been shown to be potent inhibitors of the Notch signaling pathway; they suppress cellular proliferation and induce apoptosis in several cancer cells. In the present study, we investigated the effect of N-[N-(3, 5-difluorophenacetyl-L-alanyl)]-S-phenylglycine t-butyl ester (DAPT, γ-secretase inhibitor) on the cell proliferation and apoptosis in Ishikawa endometrial cancer cells. Real-time PCR detected mRNA derived from NOTCH1 and HES1, which are target genes of the Notch signaling pathway, in Ishikawa endometrial cancer cells. After blocking Notch signaling, cellular proliferation decreased, accompanied by increased expression of p21 mRNA and decreased expression of the cyclin A protein. Furthermore, blockade of Notch signaling induced apoptosis. These results suggest that the Notch signaling pathway may be involved in cell proliferation through cell cycle regulation and apoptosis in Ishikawa endometrial cancer cells. Inhibition of the Notch signaling pathway by γ-secretase inhibitors is expected to be a potential target of novel therapeutic strategies for endometrial cancer.

Objective: It was the aim of this study to evaluate the diagnostic utility of Notch-1 immunocytochemistry in distinguishing endometrial glandular and stromal breakdown (EGBD) from endometrial adenocarcinoma in endometrial cytology., Study Design: Samples of normal endometrium, EGBD and endometrial adenocarcinoma were subjected to immunocytochemical staining for Notch-1, and we examined the labeling index (LI) of Notch-1 (the ratio of intranuclear Notch-1-positive cells to total cells). We compared (1) the Notch-1 LI in normal endometrium, (2) the Notch-1 LI between normal endometrium and endometrial adenocarcinoma, and (3) the Notch-1 LI in normal endometrium, EGBD and endometrial adenocarcinoma., Results: In analysis item 1, the LI of Notch-1 was 32.9 ± 8.4, 19.4 ± 8.2 and 12.5 ± 7.5% in proliferative endometrium, secretory endometrium and atrophic endometrium, respectively. In analysis item 2, the LI of Notch-1 in endometrial adenocarcinoma was 45.2 ± 7.4%, which was significantly higher than that in normal endometrium. In analysis item 3, the LI of Notch-1 in EGBD was 31.3 ± 8.3%, which was significantly lower than that in endometrial adenocarcinoma., Conclusion: In conclusion, Notch-1 immunocytochemistry is a useful method for distinguishing between EGBD and endometrial carcinoma in endometrial cytology., (Copyright © 2012 S. Karger AG, Basel.)

Objective: The purpose of this study was to examine the utility of SurePath-liquid-based cytology (LBC) compared to conventional cytological preparations (CCP) in the identification of endometrial carcinoma., Methods: During a 13-month period, direct endometrial samples were collected from 120 patients using the Uterobrush. The material comprised 30 cases each of endometrial carcinoma, proliferative endometrium, secretory endometrium and atrophic endometrium. The following points were investigated:(i) the frequency of cell clumps in endometrial carcinoma; (ii) the area of cell nuclei; (iii) overlapping nuclei., Results: (i) Comparison of the frequency of cell clumps with irregular protrusion pattern and papillo-tubular pattern showed no statistically significant difference in either type of cell clump between CCP and LBC. (ii) Comparison of the nuclear area of cells showed a sequential decrease from endometrial carcinoma to secretory endometrium, to proliferative endometrium and to atrophic endometrium, which was significant in CCP and LBC. (iii) Nuclear area was significantly lower with LBC compared with CCP in endometrial carcinoma, secretory endometrium and proliferative endometrium but not atrophic endometrium. (iv) Comparison of the degree of overlapping nuclei showed a sequential decrease from endometrial carcinoma to proliferative endometrium, to secretory endometrium and to atrophic endometrium, which was significant in both CCP and LBC. (v) Comparison of the degree of overlapping nuclei between CCP and LBC showed no significant difference for normal types of endometrium, but LBC had significantly higher values (P < 0.0001) in endometrial carcinoma than in CCP., Conclusions: The results of this study revealed that applying diagnostic criteria used in CCP to LBC was easy to achieve, because LBC had excellent cytoarchitectural preservation and cells were well presented. Although we have not examined all cytological features of malignancy and have not considered atypical hyperplasia, we believe that this method may be a useful tool in the diagnosis of endometrial cytology.

Papillary metaplastic changes especially occur in both non-neoplastic and neoplastic endometrium. We tried to investigate to assess the relationship between endometrial cytologic diagnosis and papillary metaplasia. The material consists of 160 cases of cytologic smears obtained by direct sampling of the endometrial cavity comprising 54 cases of normal proliferative endometrium (NPE), 36 cases of glandular and stromal breakdown (EGBD), and 70 cases of endometrial hyperplasia without atypia (EH). As for the correlation between the appearance of papillary metaplasia and cytological diagnosis, a statistical significance test was performed. The material consists of 40 cases of cytologic smears examined by direct sampling of the endometrial cavity comprising 10 cases of EGBD with papillary metaplasia, 10 cases of G1 without papillary metaplasia, 10 cases of NPE without papillary metaplasia, and 10 cases of EH without papillary metaplasia. Using the comparison between appearance of papillary metaplasia and cytological diagnosis, a significant difference was only seen in the rate of correct diagnoses in EGBD cases. The nuclear area of papillary metaplastic cells in EGBD was 888.8, G1 was 928.7, NPE was 682.0, and EH was 722.2. Significant difference was observed between ECC cells in EGBD to NPE, between papillary metaplastic cells in EGBD to EH, between G1 to NPE, or between G1 to EH. This study provides new and important information on the correlation between endometrial cytological diagnosis and papillary metaplastic changes., (2009 Wiley-Liss, Inc.)

Various metaplastic changes may be present in endometrium, in which also cellular atypias may often be observed. Particularly, eosinophilic and ciliated changes (ECCs) occur in both nonneoplastic and neoplastic endometrium. This may cause confusion in the cytodiagnosis. This study was enterprised to investigate the possible help of immunocytochemical and cytogenetic study in the diagnostic and biologic assessment of ECC cells. In immunocytochemistry for p53 protein, Ki-67, and cyclin A, the material consists of 40 cases of cytologic smears examined by direct sampling of the endometrial cavity comprising 30 cases of ECC in endometrial glandular and stromal breakdown (EGBD) and 10 cases of well-differentiated adenocarcinoma (G1). After cytodiagnosis, immunostaining for p53 protein, Ki-67, and cyclin A was performed on multiple wet-fixed slides from each single case to evaluate the immunoreactivity, intensity of nuclear staining, and nuclear labeling index (N-LI). The intensity of nuclear staining was scored as negative (0), weak (1), moderate (2), or strong (3), and the N-LI was scored as less than 10% (0), from 10% to 25% (1), from 26% to 50% (2), or more than 50% (3), and the final score was calculated by adding both partial scores. A statistical significance test was performed by using Mann-Whitney U test, and the result was judged as significant when the P value was less than .05. For genetic mutation analysis of p53, the material comprised 6 cases of EGBD in which a high score was measured with immunocytochemistry for p53 protein, and the presence of ECC was confirmed on the hematoxylin and eosin. The ECC cells on paraffin-embedded specimens were captured using laser capture microdissection technology. Mutations in p53 gene (exons 5-8) were examined using DNA sequencing analysis. In immunocytochemistry for p53 protein, Ki-67, and cyclin A, the proportions of immunoreactive cells for p53 were statistically higher in ECC compared with those of G1 (P < .05). The proportions of the immunoreactive cells for Ki-67 and cyclin A were statistically higher in G1 compared with those of ECC (P < .05). (2) In genetic mutation analysis of p53, DNA sequencing of p53 in 6 cases revealed no mutations. The percentage of immunoreactive cells for p53 protein were higher in ECC than in G1, but the mutation point was not confirmed in genetic mutation analysis. The differential expression of these biologic parameters in ECC cells could be considered of possible relevance to the cytopathologic diagnosis in the future.

Background: For the current report, the authors examined the characteristic features of morphology and molecular biology of phosphatase and tensin homolog (PTEN), beta-catenin, and p53 immunocytochemistry in endometrial carcinoma by using thin-layer cytologic preparations., Methods: During a 6-month period, 120 endometrial samples were collected directly by using the Uterobrush, and thin-layer specimens were prepared. Immunocytochemical expression levels of PTEN, beta-catenin, and p53 were investigated by using 40 specimens of endometrial carcinoma (EC), and 30 specimens each of proliferative endometrium, secretory endometrium, and atrophic endometrium., Results: For PTEN immunoreactivity, the a cutoff value of 50% PTEN expression appeared to be useful for the correct diagnosis of EC in endometrial cytology. For beta-catenin immunoreactivity, an increase in cytoplasmic and nuclear beta-catenin expression and a loss of beta-catenin expression appeared to be useful for the correct diagnosis of EC in endometrial cytology and may aid in the stratification of EC into low grade and high grade EC. For p53 immunoreactivity, the application of a cutoff score >or=4 for nuclear p53 expression appeared to be useful for the diagnosis of high-grade EC in endometrial cytology., Conclusions: Immunocytochemical findings from a combination of PTEN, beta-catenin, and p53, in addition to cytomorphologic features, appeared to be useful for the more accurate diagnosis of EC in endometrial cytology., ((c) 2008 American Cancer Society.)

PTEN and beta-catenin are the most common genes for which genetic abnormalities are found in endometrioid adenocarcinoma (type I) and even in their precursors. Currently, the World Health Organization (WHO) classifies endometrial hyperplasia as a premalignant disease. However, one of the problems in the current WHO endometrial hyperplasia schema is that it is not always a reproducible classification system. Subsequently, the alternative molecular genetics and morphometric-based classification, referred to as the endometrial intraepithelial neoplasia (EIN) classification system, has been proposed. We reclassified endometrial lesions in Japanese women using the EIN category and compared them with the results of PTEN as well as beta-catenin immunohistochemistry. A total of 117 cases that were initially diagnosed as endometrial hyperplasia according to WHO classification were reevaluated histopathologically by the EIN diagnosis category. They were classified into 38 EIN and 32 benign architectural changes of unopposed estrogen (BAC), and 47 cases were excluded. In addition, for comparison, we examined 20 cases of normal proliferative endometrium (NPE). Subsequently, the expressions of PTEN and beta-catenin were analyzed immunohistochemically. Glandular epithelium was positive for PTEN in all the cases of NPE (20/20), whereas 12.5% (4/32) of BAC and 34.2% (13/38) of EIN were PTEN-null (negative). Endometrial intraepithelial neoplasia was significantly less frequently positive for PTEN than NPE (P < .025). The nuclear staining for beta-catenin was seen in 26.3% (10/38) of EIN cases, and the intensity was generally strong. Instead, none of the BAC or NPE showed positive nuclear staining. Thus, the nuclear staining was statistically more frequently seen in EIN than in the other 2 categories (P < .025 for each). In addition, 22 of 38 EIN cases (57.9%) were either PTEN-negative or nuclear beta-catenin-positive. This combination was statistically significantly more frequently seen than BAC (4/32, 12.5%) (P < .001) and NPE (0/20, 0%) (P < .0001). Immunohistochemical loss of PTEN and positive nuclear staining of beta-catenin were frequently seen in EIN but were not seen in NPE cases in Japanese women. The combination of PTEN-negative/beta-catenin-positive results may become the reliable marker for detecting EIN.

Background: Because cellular atypia is often limited in endometrial hyperplasia and well-differentiated endometrial adenocarcinoma (WHO Grade 1 adenocarcinoma), diagnostic criteria for endometrial cytology have not been fully established. New diagnostic criteria based on the composition and architecture of tissue fragments (cytoarchitecture) in the smears were used in the present study. Cytologic features are of less importance because the distinction between endometrial hyperplasia and Grade 1 adenocarcinoma relies more on architectural features than cellular changes. Cell clumps of various size are usually collected abundantly with cytologic material using a disposable scraping device and it was noticed that those cell clumps reflected the histologic architecture. The purpose of the current study was to determine the form of the cytoarchitecture that reflects the histologic structure and to examine the cellular features in endometrial hyperplasia and Grade 1 adenocarcinoma., Methods: The frequency of each type of cell clump (tube or sheet-shaped pattern, dilated or branched pattern, irregular protrusion, and papillotubular pattern) were obtained from 49 cases of normal proliferative endometrium (NPE) (patient age range, 28-51 yrs; average age, 39.9 yrs), 63 cases of endometrial hyperplasia without atypia (EH) (patient age range, 35-65 yrs; average age, 47.7 yrs), 13 cases of endometrial hyperplasia with atypia (AEH) (patient age range 47-65 yrs; average age, 53.8 yrs), and 49 cases of Grade 1 adenocarcinoma (patient age range, 42-73 yrs; average age, 58.9 yrs)., Results: Certain characteristics of the cytoarchitecture were observed. In the NPE, cell clumps with a tube or sheet-shaped pattern were found in 97.5% of cases. In the EH, cell clumps with a dilated or branched pattern were found in 34.9% of cases. In the Grade 1 adenocarcinoma, cell clumps with irregular protrusions were found in 61.8% cases, whereas a papillotubular pattern was present in 29.7% of cases., Conclusions: The results of the current study revealed that cytoarchitectural criteria appear to be more useful for the cytologic assessment of endometrial lesions, especially for the diagnosis of endometrial hyperplasia and Grade 1 adenocarcinoma., (Copyright 2006 American Cancer Society.)

p27 is regarded as a cyclin-dependent kinase inhibitor of the G1-to-S cell cycle progression by suppressing the kinase activity of cyclin/cyclin-dependent kinase complex. This study aimed to investigate p27 expression in the normal endometrium and endometrioid adenocarcinoma of the uterine corpus and the correlation of its expression with cell proliferation and clinicopathological parameters. Tissue samples of 127 endometrioid adenocarcinomas and 15 normal endometria were used in the study. Immunohistochemical staining for detecting p27 and Ki-67 was performed by the labelled streptavidin-biotin method on formalin-fixed and paraffin-embedded tissue samples. The expression was given as the labelling index, which indicates the percentage of positive nuclei. p27 staining was observed in the nuclei of the glandular cells in the functional layer of the secretory phase endometrium, whereas it was negative in those of the proliferative phase. In endometrioid adenocarcinomas, the labelling index of p27 expression paradoxically increased more significantly in the higher histological grades and was correlated with that of Ki-67. The high level of p27 expression was associated with clinicopathological parameters such as FIGO stage, lymph node metastasis, lymphovascular space involvement and myometrial invasion. High p27 expression was linked to higher grades of endometrioid adenocarcinoma, cell proliferation and some clinical prognostic factors. These results indicate that p27 might be an indicator of poor prognosis., (Copyright 2002 Cancer Research UK)

Objective: Vascular endothelial growth factor (VEGF)--that activates endothelial cell growth--has been considered to induce angiogenesis, which is indispensable to tumor-genesis and progression. In this study, an immunohistochemical analysis was carried out to clarify the correlation of VEGF expression with angiogenesis, p53 expression--of which the wild-type is considered to suppress VEGF expression--and histologic grade in endometrial carcinoma., Study Design: Immunohistochemical staining for detecting VEGF protein, factor VIII-related antigen of endothelial cells, and p53 protein was performed by the labeled streptavidin-biotin method on the formalin-fixed and paraffin-embedded tumor tissue of 104 patients with endometrial (endometrioid) carcinoma, including 69 with well-differentiated, 25 with moderately differentiated, and ten with poorly differentiated adenocarcinoma., Results: The labeling index of p53 expression was 19.9+/-28.8% in the high VEGF group, whereas in the low VEGF group it was 12.2+/-17.0%, showing that VEGF expression was significantly correlated with p53 expression (P<0.05). VEGF expression, however, was not correlated with either the number of microvessels in the tumor area or tumor histologic grade., Conclusion: VEGF expression was not a single specific indicator of angiogenesis in endometrial carcinoma, whereas it was significantly correlated with p53 expression.

Objective: To evaluate the usefulness of endometrial aspiration cytology for the preoperative diagnosis of ovarian carcinoma., Study Design: A total of 210 patients with ovarian carcinoma were investigated by endometrial aspiration cytology., Results: Fifty-five of 210 patients (26.2%) had positive endometrial aspiration cytology. The positive rates of endometrial cytology were 3.9% in stage I, 23.8% in stage II, 36.5% in stage III and 53.3% in stage IV. When classified by histologic type, the positive rates of endometrial cytology in patients with serous adenocarcinoma, mucinous adenocarcinoma, clear cell adenocarcinoma, undifferentiated carcinoma and yolk sac tumor were 38.9%, 11.8%, 21.1%, 16.7% and 16.7%, respectively. One hundred twenty-eight of 210 patients (61.0%) were positive on peritoneal cytology, and 54 of these 128 cases (42.2%) were also positive on endometrial cytology. The positive rates of endometrial cytology were especially high in patients with serous adenocarcinoma (51.2%) and those with clear cell adenocarcinoma (40.0%) among those who were positive on peritoneal cytology. Of 74 patients who were negative on peritoneal cytology, only one (1.4%) with mucinous adenocarcinoma had positive endometrial cytology. Hysterectomy was performed on 130 patients, and the positive rate of endometrial cytology was 100% in 4 patients with endometrial invasion and 15.9% in 126 cases without invasion., Conclusion: Endometrial aspiration cytology can detect ovarian carcinoma cells not only in patients with endometrial involvement but also in patients with positive peritoneal cytology. Endometrial aspiration cytology appears to be useful for the preoperative diagnosis of ovarian carcinoma.