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Objective: The impact of systematic retroperitoneal lymphadenectomy (SRL) remains controversial in patients with advanced ovarian clear-cell carcinoma (CCC) who are optimally debulked., Methods: Between 1986 and 2017, a total of 3,227 women with epithelial ovarian carcinoma were analyzed in a multi-institutional study. Among them, 166 optimally debulked women with stage IIB-IV CCC were collected (residual tumor of <1 cm). All patients were divided into 2 groups: 1) Group I (n=112): underwent standard radical surgery with SRL, 2) Group II (n=54): underwent non-staging limited surgery. The pathological slides were assessed based on central pathological review. Oncologic outcomes were compared between the two groups using a propensity score (PS)-matching technique to adjust for various clinicopathologic factors., Results: The median follow-up duration of all surviving women was 52.8 (1.6-184.2) months. Overall, 88 patients (53.0%) experienced recurrence and 68 patients (41.0%) died of the disease. In the original cohort, the 5-year overall survival (OS) rates of groups I and II were 57.9 and 64.9%, respectively (log-rank p=0.415). In the PS-adjusted cohort, the 5-year OS rates were 64.9 and 58.8% in women in groups I and II, respectively (p=0.453). Furthermore, in the PS-matched cohort after adjustment for multiple clinicopathologic factors, there was no significant difference in OS between the 2 groups (group I vs. group II; hazard ratio=1.170; 95% confidence interval=0.633-2.187; p=0.615)., Conclusions: This study suggests that the performance of SRL including radical surgery may not lead to a significant improvement in the oncologic outcome of advanced CCC patients with optimal cytoreduction., Competing Interests: No potential conflict of interest relevant to this article was reported., (Copyright © 2020. Asian Society of Gynecologic Oncology, Korean Society of Gynecologic Oncology.)

Background: Spectrin αII contributes to cisplatin and carboplatin resistance in ovarian serous carcinoma cells, and its expression in surgical specimens is a valid predictor of prognosis. We sought to identify effective drugs for spectrin αII-mediated cisplatin-resistant cells., Materials and Methods: We employed SKOV3 cells with small interfering RNA-mediated spectrin αII downregulation, serous carcinoma cells (NOS2), cisplatin-resistant cells (NOS2CR2), and oxaliplatin-resistant cells (NOS2OXR)., Results: In the drug-sensitivity test, oxaliplatin was not affected by the inhibition of spectrin αII expression and was effective for cisplatin-resistant NOS2CR2 cells. NOS2OXR cells did not express higher levels of spectrin αII compared to NOS2 in western blot analysis. Six non-platinum anticancer drugs were not affected by the inhibition and was effective for resistant NOS2CR2 and NOS2OXR cells. Doxorubicin exhibited potent cytotoxicity at 2 μM against both resistant cell lines., Conclusion: Pegylated liposomal doxorubicin/oxaliplatin regimen may be effective for cisplatin-resistant ovarian carcinoma with spectrin αII-overexpression., (Copyright© 2020, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Peritoneal dissemination of ovarian cancer (OvCa) arises from the surface of the peritoneum, covered by monolayer of mesothelial cells (MCs). Given that both OvCa cells and MCs are present in the same peritoneal metastatic microenvironment, they may establish cell-to-cell crosstalk or phenotypic alterations including the acquisition of platinum-resistance in OvCa cells. Herein, we report how OvCa-associated mesothelial cells (OCAMs) induce platinum-resistance in OvCa cells through direct cell-to-cell crosstalk. We evaluated mutual associations between OvCa cells and human primary MCs with in vitro coculturing experimental models and in silico omics data analysis. The role of OCAMs was also investigated using clinical samples and in vivo mice models. Results of in vitro experiments show that mesenchymal transition is induced in OCAMs primarily by TGF-β1 stimulation. Furthermore, OCAMs influence the behavior of OvCa cells as a component of the tumor microenvironment of peritoneal metastasis. Mechanistically, OCAMs can induce decreased platinum-sensitivity in OvCa cells via induction of the FN1/Akt signaling pathway via cell-to-cell interactions. Histological analysis of OvCa peritoneal metastasis also illustrated FN1 expression in stromal cells that are supposed to originate from MCs. Further, we also confirmed the activation of Akt signaling in OvCa cells in contact with TGF-β1 stimulated peritoneum, using an in vivo mice model. Our results suggest that the tumor microenvironment, enhanced by direct cell-to-cell crosstalk between OvCa cells and OCAMs, induces acquisition of platinum-resistance in OvCa cells, which may serve as a novel therapeutic target for prevention of OvCa peritoneal dissemination., (© 2020 The Authors. International Journal of Cancer published by John Wiley & Sons Ltd on behalf of UICC.)

Objective: The impact of 'standard full-staged radical surgery (SRS)' on overall survival (OS) in elderly patients with early-stage epithelial ovarian cancer (EOC) remains unclear. In the current study, we investigated the impact of SRS on OS in elderly patients with early-stage EOC in a multicentric analysis using a propensity score (PS)-matching technique., Methods: Between 1986 and 2017, 3227 patients with EOC were registered and accumulated by the Tokai Ovarian Tumor Study Group, consisting of 14 collaborating institutions, after a central pathological review. Among them, 204 elderly patients aged older than or equal to 65 years who had a stage I EOC were analyzed, including 72 patients who had received SRS (Group I) and 132 who had undergone non-SRS limited surgery (Group II). Oncologic outcomes were compared between the two groups using a PS-matching technique to adjust for various clinicopathologic risk factors., Results: The median follow-up duration of all surviving patients was 55.9 months. Consequently, 54 patients (26.5%) developed recurrence. In addition, 33 patients (16.2%) died of the disease. In the original cohort, the 5-year OS rates of Groups I and II were 95.8 and 82.3%, respectively. We identified a marginally significant difference between the two groups (Log-rank: P = 0.086). In the PS-matched cohort after adjustment for multiple clinicopathologic factors, there was no significant difference in OS between the two groups [OS (Group I vs. II), HR: 0.766 (95% CI: 0.271-2.165), P = 0.615]., Conclusions: After adjustment for clinicopathologic factors, non-SRS limited surgery may not worsen the oncologic outcome in elderly women with early-stage EOC. A large-scale clinical study is necessary to validate the findings., (© The Author(s) 2019. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Owing to its rarity, the carcinogenesis and molecular biological characteristics of squamous cell carcinoma arising from mature teratoma remain unclear. This study aims to elucidate the molecular background of malignant transformation from the aspects of microRNA (miRNA) profiling. We examined 7 patients with squamous cell carcinoma and 20 patients with mature teratoma and extracted their total RNA from formalin-fixed paraffin-embedded tissues. Then we prepared small RNA libraries and performed comprehensive miRNA sequencing. Heatmap and principal component analysis revealed markedly different miRNA profiling in cancer, normal ovarian and mature teratoma tissues. Then we narrowed down cancer-related miRNAs, comparing paired-cancer and normal ovaries. Comparisons of cancer and mature teratoma identified two markedly upregulated miRNAs (miR-151a-3p and miR-378a-3p) and two markedly downregulated miRNAs (miR-26a-5p and miR-99a-5p). In addition, these findings were validated in fresh cancer tissues of patient-derived xenograft (PDX) models. Moreover, several miRNAs, including miR-151a-3p and miR-378a-3p, were elevated in the murine plasma when tumor tissues were enlarged although miR-26a-5p and miR-99a-5p were not elucidated in the murine plasma. Finally, we performed target prediction and functional annotation analysis in silico and indicated that targets genes of these miRNAs markedly correlated with cancer-related pathways, including 'pathway in cancer' and 'cell cycle'. In conclusion, this is the first study on miRNA sequencing for squamous cell carcinoma arising from mature teratoma. The study identified four cancer-related miRNAs that were considered to be related to the feature of malignant transformation. Moreover, miRNAs circulating in the murine plasma of the PDX model could be novel diagnostic biomarkers., (© The Author(s) 2019. Published by Oxford University Press.)

Background: The aim of this study was to investigate how much the risks of recurrence and death are increased as a consequence of selecting fertility-sparing surgery (FSS) in young women with epithelial ovarian cancer (EOC)., Methods: After a central pathological review and search of the medical records from 14 collaborating hospitals, a non-randomized, observational cohort study was conducted between 1987 and 2015, including 1183 women with stage I EOC. Finally, a total of 285 patients with stage I EOC at reproductive age were recruited. Oncologic outcomes were compared between the FSS (N = 101) and radical surgery (RS) group (N = 184) using a propensity score (PS)-matching technique to adjust for relevant risk factors: the age, substage, histological type, grade, CA125 values, ascites cytology, ascites volume, and chemotherapy., Results: During 66.0 months (median) of follow-up, 42 patients (14.7%) developed recurrence, and 31 patients (10.9%) died. In the original cohort, there was no significant difference in overall survival (OS) or recurrence-free survival (RFS) between the FSS and RS groups {Log-rank: OS (P = 0.838), RFS (P = 0.377)}. In the PS-matched cohort after adjustment for multiple clinicopathologic factors, there was no significant difference in RFS or OS between the FSS and RS groups {RFS (FSS vs. RS), HR: 1.262 (95% CI: 0.559-2.852), P = 0. 575; OS (FSS vs. RS), HR: 1.206 (95% CI: 0.460-3.163), P = 0.704}., Conclusions: After adjustment for clinicopathologic factors, FSS in itself may not worsen the oncologic outcome in young women with early-stage EOC. A large-scale clinical study is necessary to validate the findings.

Background: Clear-cell carcinoma (CCC) in reproductive-age women is likely to become an increasingly critical issue regarding possibilities of infertility, hormonal dysfunction, and mortality. The aim of this study was to examine the long-term oncologic outcome and its prognostic indicators based on a multicentric cohort of young patients with CCC., Patients and Methods: During the period of 1990-2015, a total of 164 patients aged 45-year-old or younger were enrolled in the study. Clinicopathologic data of these young patients with CCC collected under a centralized pathological review system were subjected to uni- and multivariable analyses to evaluate overall survival (OS)., Results: The median follow-up was 73.8 months (range 5.2-244.2) in the surviving patients. Among these patients, 104 (63.4%) had FIGO I disease, and 22 (13.4%), 31 (18.9%), and 7 (4.3%) had II, III, and IV disease, respectively. The 5-year OS rate was 74.5%. On stratification by the FIGO stage, the 5-year OS rates were as follows: stage I (90.2%), stage II (57.9%), and stage III/IV (39.3%), respectively (P < 0.0001). Confining analysis to stage I patients, there was no difference in OS between those who underwent fertility-sparing surgery and those who received radical surgery (P = 0.1593). In relapsed patients, the median survival after recurrence was 11.6 months. In multivariable analysis of stage I patients, the capsule status was an independent prognostic indicator of OS {IC2/IC3 vs. IA/IC1: HR 4.293 (95% CI 1.140-16.422), P = 0.0318}., Conclusion: CCC patients staged greater than IC2/IC3 show a markedly increased risk of mortality. Thus, it is important to diagnose patients staged under IC2/IC3.

Background: Occasionally, ovarian tumors are found to have originated from non-ovarian organs as metastatic lesions since the ovary is a common site of metastasis from many cancers. The aim of the current study was to estimate the long-term oncologic outcome of patients with metastatic mucinous ovarian carcinoma (MmOC) in comparison with those with primary mucinous ovarian carcinoma (PmOC) at an advanced stage., Materials and Methods: The data of one hundred and sixty-seven patients with mucinous ovarian cancer, including 91 patients with MmOC from the digestive organs and 76 patients with stage III-IV PmOC, were retrospectively analyzed. The prognostic significances of clinicopathologic factors were evaluated employing both uni- and multivariable analyses. Pathological slides were evaluated based on centralized pathological review., Results: The median age of patients with PmOC and MmOC was 55 (18-81) and 51 years (30-82), respectively. With follow-up of a total of 167 patients, 145 patients (86.8%) developed recurrence. In addition, 122 patients (73.0%) died of the disease. Regardless of the residual tumor status, patients with PmOC did not a show a significantly poorer OS than those with MmOC. Furthermore, in a Cox multivariable hazard model, after adjustment for various clinicopathologic confounders, a gastric cancer (GC)-originated tumor and larger residual tumor were significant predictors of poorer OS [GC (vs. PmOC): HR (95% CI) 2.205 (1.303-3.654), P = 0.0036]., Conclusion: The oncologic outcome of patients with MmOC was extremely poor; however, it was almost the same as that of those with PmOC. We should recognize MmOC derived from gastric carcinoma as a highly aggressive malignancy.

Background: Fertility-sparing surgery (FSS) has mainly been chosen for young women with ovarian-confined/well-differentiated epithelial ovarian cancer (EOC). In general, FSS consists of at least conservation of contralateral ovary and the uterus with a staging surgery. However, information on the clinical outcome in women who underwent cystectomy as a fertility-preserving option is lacking., Methods: After a central pathological review and search of the medical records from multiple institutions between 1987 and 2015, a total of eight early-stage EOC patients treated with cystectomy as FSS were retrospectively evaluated. Diagnosis and staging were based on International Federation of Gynecology and Obstetrics criteria (2014). Surgery consisted of uni- or bilateral cystectomy. The oncologic and reproductive outcomes were assessed., Results: The median age was 29 years (range 26-38 years). The median follow-up time was 103.6 months (range 42.2-218.3 months). The stage was IA in 3, IC1 in 4, and IC3 in one patient. Five patients received adjuvant chemotherapy. After cystectomy, two patients experienced recurrence in the pelvic cavity and bilateral ovaries, respectively. The former patient died of the disease 42 months after cystectomy, and conversely, the latter one was rescued by subsequent radical surgery. Four full-term childbirths were observed in three patients., Conclusions: Although oophorectomy is considered as an appropriate fertility-preserving operation, cystectomy may be an unavoidable option when it is the only surgical procedure available. It is desirable to verify the utility by accumulating larger numbers of patients through a future registry system.

Objective: Complete tumor resection is considered essential in the management of patients with ovarian clear-cell carcinoma. There is a debate regarding whether patients with recurrent ovarian clear-cell carcinoma benefit from secondary cytoreductive surgery., Methods: Details of patients with clear-cell carcinoma were collected by the Tokai Ovarian Tumor Study Group (Nagoya University Hospital and 13 affiliated institutions) and evaluated between January 1990 and December 2015. Histology was confirmed after central pathological review. The primary endpoint of the study was disease-free survival after secondary cytoreductive surgery. Distributions of events were evaluated using the χ 2 test. Survival analysis was based on the Kaplan-Meier method. Survival curves were compared using the log-rank test. A value of p<0.05 was considered significant., Results: A total of 169 patients who underwent secondary cytoreductive surgery (N=25) or medical management (N=144) for recurrent clear-cell carcinoma were collected. The median age for patients undergoing secondary cytoreductive surgery was 50 years (range 35-66). Overall, 18 patients had complete resection. In patients who underwent secondary cytoreductive surgery, the median disease-free and post-recurrence survival periods were 10.9 months and 21.2 months, respectively. Moreover, among 18 patients who underwent complete resection, seven showed no evidence of disease during the observation periods. The median post-recurrence survival periods of patients with complete or incomplete resection were 30.1 months and 10.4 months, respectively (p=0.002). On stratification by the recurrence site, patients with intraperitoneal recurrence showed poorer post-recurrence survival than those with recurrence at other sites (p=0.016). However, comparison between the secondary cytoreductive surgery group versus the medical management group showed there was no difference in post-recurrence survival, even when considering complete tumor resection (p=0.114)., Conclusion: Patients with intraperitoneal recurrence or incomplete tumor resection had the worst survival after secondary cytoreductive surgery., Competing Interests: Competing interests: None declared., (© IGCS and ESGO 2019. No commercial re-use. See rights and permissions. Published by BMJ.)

Malignant ovarian neoplasm is one of the most lethal malignancies among cancers of the female reproductive system. Occasionally, these tumors originate from non-ovarian organs as metastatic lesions since the ovary is a frequent metastatic target of many cancers. However, there limited clinical information on metastatic ovarian carcinoma (MOC) and its hallmarks are unknown. During the period of 1986-2015, 4,284 patients with malignant ovarian neoplasm were identified using the Tokai Ovarian Tumor Study Group (TOTSG) database. Of these, excluding borderline malignant tumor, 3,478 patients with malignant ovarian cancer were extracted. The pathological slides were evaluated under central pathological review. Among them, a total of 143 (4.1%) patients with MOC were identified. The median age of patients with MOC was 54 (29-82) years. The most and second most frequent original tumors were colorectal (43%, N=62) and gastric (29%, N=42) carcinoma, respectively. The rates of carcinoma of the appendix, breast, and pancreas were 8, 6, and 4%, respectively. This is the one of the largest studies clarifying the rates of MOC among malignant ovarian neoplasms. Although the rate is low, we should keep in mind that MOC, particularly from colorectal and gastric cancer should be considered when encountering clinical practice of ovarian cancer., Competing Interests: The authors declare that they have no conflicts of interest.

Endometriosis, characterized by the presence of extra-uterine endometrium, is a common gynecologic disorder in reproductive-age women. Although the detailed molecular mechanism of etiology remains unelucidated, recent studies have gradually revealed both genetic and epigenetic backgrounds of the development of endometriosis. In clinical practice, endometriosis has been recognized as a precursor lesion of several types of malignancies and endometriosis-associated carcinoma. An imbalance between reactive oxygen species and local antioxidants has been reported to contribute to the development of endometriosis-associated carcinoma as well as the pathophysiology of this disease through a systemic inflammatory response in the peritoneal cavity. This review mainly presents an epidemiology, possible etiology of endometriosis, precursor lesions, molecular features, and the association between the microenvironmental accumulations of oxidative stress in endometriosis-associated ovarian cancer progression., (Copyright © 2018 Elsevier Inc. All rights reserved.)

The mesothelium, covered by a continuous monolayer of mesothelial cells, is the first protective barrier against metastatic ovarian cancer. However, mesothelial cells release tumor-promoting factors that accelerate the process of peritoneal metastasis. We identified cancer-associated mesothelial cells (CAMs) that had tumor-promoting potential. Here, we found that plasminogen activator inhibitor-1 (PAI-1) induced the formation of CAMs, after which CAMs increasingly secreted the oncogenic factors interleukin-8 (IL-8) and C-X-C motif chemokine ligand 5 (CXCL5), further promoting the metastasis of ovarian cancer cells in a feedback loop. After the formation of CAMs, PAI-1 activated the nuclear factor kappa B (NFκB) pathway in the CAMs, thus transcriptionally upregulating the expression of the downstream NFκB targets IL-8 and CXCL5. Moreover, PAI-1 correlated with peritoneal metastasis in ovarian cancer patients and indicated a poor prognosis. In both ex vivo and in vivo models, after PAI-1 expression was knocked down, the metastasis of ovarian cancer cells decreased significantly. Therefore, targeting PAI-1 may provide a potential target for future therapeutics to prevent the formation of CAMs and alleviate peritoneal metastasis in ovarian cancer patients., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Kinesin family member 20A (KIF20A), which is involved in cytokinesis and intracellular transportation, has been recently reported to be upregulated in several malignancies and may contribute to chemotherapeutic resistance. We examined the distribution and expression of KIF20A in clear‑cell carcinoma (CCC) of the ovary to elucidate its clinical significance and molecular mechanism. Paraffin sections from ovarian CCC tissues (N=43) were immunostained with KIF20A antibody, and the staining intensities were semi‑quantitatively evaluated. Furthermore, we investigated whether silencing of KIF20A contributes to the proliferation‑inhibitory potential using CCC cells. During the observational period, 18 patients (41.9%) developed recurrence. The median time to recurrence was 11.5 months. Patients in the high KIF20A expression group showed poorer progression‑free survival (PFS) and overall survival (OS) than those in the low expression group (P=0.0443 and P=0.0478, respectively). In multivariable analyses, KIF20A expression was also a significantly independent indicator of PFS and a marginally significant indicator of OS [PFS: HR (high vs. low), 5.488; 95% CI, 1.410‑24.772 (P=0.0136); OS: HR, 2.835; 95% CI, 0.854‑11.035, (P=0.0897)]. In in vitro studies, the ovarian CCC cell proliferation was significantly decreased by KIF20A silencing or in the presence of KIF20A inhibitor in CCC cells. Cell cycle G2/M arrest and a higher apoptosis‑induced fraction were more frequently observed in si‑KIF20A‑transfected CCC cells than in the control cells. Although the present study was preliminary, these data indicate the possible involvement of KIF20A in the proliferation of CCC, suggesting that targeting this molecule may contribute to reversing the malignant potential consequently affecting the oncologic outcome of CCC patients.

Background: Photodynamic therapy (PDT) is known as a minimally invasive treatment for cancer. 5-Aminolevulinic acid (ALA) is a precursor of the photosensitizing agent protoporphyrin IX (PpIX). Patients with ovarian clear-cell carcinoma (CCC) have poorer prognoses than those of patients with other histological CCC types. We evaluated the efficacy of ALA-PDT on CCC cells in vitro., Methods: We used seven human CCC cell lines to measure the cytotoxicity of ALA-PDT. PpIX production in cancer cells was measured using a micro-plate reader. Quantitative real-time PCR was performed to assess the mRNA levels of genes involved in the accumulation of PpIX in cancer cells. Additionally, we measured the enhancement in cytotoxicity with the use of an ABCG2 inhibitor., Results: We found that three cell lines were highly sensitive to ALA-PDT. In contrast, one cell line was resistant to ALA-PDT. The cytotoxicity of ALA-PDT varied among CCC cell lines. The IC50 values of ALA-PDT for the CCC cell lines had a wide range (30-882μM). The cytotoxicity of ALA-PDT was correlated with the intracellular PpIX accumulation. The cell lines sensitive to ALA-PDT expressed PEPT1 (an ALA uptake transporter). The cell line resistant to ALA-PDT expressed ABCG2 (a PpIX export transporter). In the resistant cell line, a combination treatment with both ALA and an ABCG2 inhibitor resulted in the promotion of cytotoxic sensitivity., Conclusion: The present study revealed the efficacy of ALA-PDT against CCC with chemoresistance in vitro., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Epithelial ovarian cancer (EOC) is believed to cause peritoneum dissemination through microenvironmental cell‑to-cell communication between the tumor and mesothelium, leading to the further acquisition of progressive and metastatic potentials. In the present study, we aimed to determine the role of cancer-associated mesothelial cells (CAMCs) in the promotion of tumor neovascularization and vascular permeability via enhanced vascular endothelial growth factor (VEGF) production. We examined whether a characteristic morphological change in human peritoneal mesothelial cells (HPMCs) was observed in the presence of malignant ascites and tumor-derived TGF-β. We focused on the enhanced production of VEGF in CAMCs and its crucial role in endothelial migration and tube formation. Normal HPMCs showed an epithelial morphology with a cobblestone appearance. When HPMCs were co-cultured with malignant ascites from patients with advanced EOC, a dramatic morphologic change was noted from an epithelioid pattern to an α-SMA-positive fibroblastic, mesenchymal pattern. Additionally, we found that EOC-derived TGF-β induced typical EMT-like morphological alteration in HPMCs, which was associated with CAMCs. We further discovered that CAMCs play a crucial role in the enhanced migration and tube formation of endothelial cells by the promotion of VEGF production. In conclusion, our findings indicate the possible involvement of CAMCs in the neovascularization of EOC and enhancement of vascular permeability, resulting in the formation of malignant ascites. The novel mechanism of CAMCs as a facilitator of EOC progression is displayed by microenvironmental cell-to-cell communication between EOC and the mesothelium.

Aim: Women with ovarian cancer (OC) often experience relapse and receive further repetitive chemotherapy. The objective of this study was to overview the remaining survival time after the final chemotherapy and to examine influential clinicopathologic indicators in those patients., Methods: The medical charts of deceased OC patients who had died of the disease between 2003 and 2012 were retrospectively reviewed. We investigated post-cancer-treatment survival (PCS) defined as the interval between the date of the final chemotherapy and death., Results: In all, 77 patients were enrolled. Three patients (3.9%) had received chemotherapy in the last 2 weeks. Eight (10.4%), 28 (36.4%), and 44 (57.2%) patients had received chemotherapy in the last 30, 60, and 90 days, respectively. There were no differences in either survival after recurrence or overall survival between the shorter (<75 days) and longer (≥75 days) PCS groups. On the other hand, patients in the shorter PCS group had significantly fewer chances of referral to a hospice or home-care than those in the latter group (P = 0.035). In multivariable analysis, a poorer performance status, an elevated white blood cell count, and a higher C-reactive protein value were significantly correlated with a shorter PCS (P = 0.004, 0.006 and 0.027, respectively)., Conclusion: Half of the patients received chemotherapy within 75 days of death and we did not identify any survival benefit in patients who received chemotherapy near the end of life. We should provide information to patients about their prognosis and discuss the timing of withdrawal from chemotherapy from the early stage of their recurrence., (© 2017 Japan Society of Obstetrics and Gynecology.)

Epithelial ovarian carcinoma (EOC) is associated with a poor prognosis because it shows peritoneal dissemination. To improve the prognosis, it is important to control peritoneal dissemination. However, it is still unclear how tumor cells detach from primary lesions and attach to the mesothelium. The establishment of an appropriate animal model is needed to gain an understanding of the mechanism of peritoneal dissemination in vivo. In the current study, we introduce the process from the local injection of EOC cells into the murine ovarian surface to the development of metastasis, including the peritoneum and distant organs. Female nude mice (BALB/c nu/nu) at 8 weeks of age were used. Under a microscopic field of view, EOC cells (1 x 10 5 cells/µl of medium-extracellular matrix (ECM)-based hydrogel/unilateral ovary/mouse) were injected into murine ovaries through a retroperitoneal approach from the dorsal flank. This proposed method is a less invasive procedure for the mouse and minimizes damage to the ovary. Here, we describe the methodological steps in the development of the original and metastatic tumor formation of EOC.

Anticancer drug sensitivity affects prognosis in ovarian carcinoma. Previously, we purified spectrin αII and βII tetramers from cisplatin-resistant ovarian serous adenocarcinoma cells and demonstrated that they contribute to platinum anticancer drug resistance. In this clinical study, we focused on the role of spectrin αII expression. It is our objective to demonstrate the potential of spectrin αII expression as a useful predictor of anticancer drug resistance and postoperative prognosis in epithelial ovarian carcinoma. Spectrin αII expression in the ovarian adenocarcinoma surgical specimens of 193 patients was examined by immunohistochemical staining. Staining strength was scored 3+, regarded as positive expression, and 2+, 1+, and 0, regarded as non-positive expression. Prognoses obtained from clinical records were evaluated by statistical analysis. In the 193 cases studied, positive spectrin αII expression was associated with worse overall survival when compared with non-positive expression (P < 0.001 by log-rank test), and spectrin αII expression was identified as an independent predictive factor of overall survival (hazard ratio[HR]: 3.77, 95% confidence interval[CI]: 1.77-8.00; P < 0.001 by multivariate Cox's proportional hazards model). In the study about progression-free survival, spectrin αII expression was not associated with prognoses. However, similar results as overall survival were obtained for survival after recurrence of the 92 recurrent cases (P = 0.0051 by log-rank test, HR: 4.49, 95% CI: 2.06-9.79; P < 0.001 by multivariate Cox's proportional hazards model). In a detailed overall survival study of 66 serous adenocarcinoma patients and 127 nonserous adenocarcinoma patients, similar results were also obtained. Spectrin αII expression is a useful predictor of anticancer drug resistance and postoperative prognosis in epithelial ovarian carcinoma.., (© 2016 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.)

Ovarian clear cell carcinomas often show a spherule-like mucoid stroma. In ascitic fluid, they form spheroids with a hollow acellular space. In spite of the absence of stromal cells, both the mucoid stroma and hollow spheroids contain abundant extracellular matrix, and one of the major components is hyaluronan. It has been suggested that tumor-derived hyaluronan plays a significant role in the formation of these structures. To clarify this, a hyaluronan inhibition assay was performed on HAC-2, a clear cell carcinoma cell line, in vitro. When hyaluronan synthesis was inhibited by 4-methylumbelliferone, HAC-2 failed to show the spherule-like accumulation of hyaluronan or hollow spheroids. Inhibition of hyaluronan synthesis was associated with the reduction of cell growth. Analysis of 28 archival ascites cytology specimens showed that clear cell carcinomas expressed hyaluronan more frequently than serous carcinomas (11 of 14 vs 3 of 14, respectively, P < 0.05). All of these facts indicate that tumor-derived hyaluronan is essential for the formation of the mucoid stroma or hollow spheroids, and that hyaluronan is also involved in the regulation of cell growth in ovarian clear cell carcinomas. The inhibition of hyaluronan synthesis could be a potential adjunctive therapy for refractory clear cell carcinomas outside the ovary., (© 2016 The Authors. Pathology International published by Japanese Society of Pathology and John Wiley & Sons Australia, Ltd.)

Here, we describe an human leukocyte antigen (HLA)-A*24:02-restricted cytotoxic T-lymphocyte (CTL) clone, 1G3, established from naïve CD8(+) T-lymphocytes obtained from a healthy donor stimulated with HLA-modified TOV21G, an ovarian cancer cell line. The 1G3 clone responds not only to ovarian cancer cells in the context of HLA-A*24:02 but also to allogeneic HLA-Cw*07:02 molecules through cross-reactive T-cell receptor recognition. Expression screening using a complementary DNA library constructed from TOV21G messenger RNA revealed that this alloreactivity was mediated through the nine-mer peptide VRTPYTMSY, derived from RNA-binding motif protein 4. To our knowledge, this study presents the first example of the allorecognition of an HLA-Cw molecule by HLA-A-restricted T-cells, thereby revealing a naturally processed epitope peptide. These findings provide the structural bases for the allorecognition of human T-cells. In addition, this study suggests that unexpected alloresponses occur in certain HLA combinations, and further study is needed to understand the mechanisms of alloreactivity for better prediction of alloresponses in clinical settings., (© 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Homeoproteins, a family of transcription factors that have conserved homeobox domains, play critical roles in embryonic development in a wide range of species. Accumulating studies have revealed that homeoproteins are aberrantly expressed in multiple tumors and function as either tumor promoters or suppressors. In this study, we show that two homeoproteins, HOXB13 and ALX4, are associated with epithelial to mesenchymal transition (EMT) and invasion of ovarian cancer cells. HOXB13 and ALX4 formed a complex in cells, and exogenous expression of either protein promoted EMT and invasion. Conversely, depletion of either protein suppressed invasion and induced reversion of EMT. SLUG is a C2H2-type zinc-finger transcription factor that promotes EMT in various cell lines. Knockdown of HOXB13 or ALX4 suppressed SLUG expression, and exogenous expression of either protein promoted SLUG expression. Finally, we showed that SLUG expression was essential for the HOXB13- or ALX4-mediated EMT and invasion. Our results show that HOXB13/SLUG and ALX4/SLUG axes are novel pathways that promote EMT and invasion of ovarian cancer cells.

Background: Patients with FIGO stage IV epithelial ovarian carcinoma have a poor but non-uniform prognosis. This study aimed to compare the survival of patients with serous or endometrioid tumours (S/E) and clear cell or mucinous tumours (non-S/E)., Methods: Data for 223 patients who underwent surgery between 1987 and 2010 and were diagnosed by centralized pathology review and were retrospectively analysed. The patients included 169 with S/E tumours and 54 with non-S/E tumours., Results: The median overall survivals (OSs) of the S/E and non-S/E groups were 3.1 and 0.9 years, respectively (P<0.001). Six patients (2.7%), all with non-S/E tumours, died within 6 weeks after the initial surgery. Multivariate OS analysis revealed that performance status, residual tumor, metastatic sites, no debulking surgery, and non-S/E tumours were independent poor prognostic factors. For patients with non-S/E tumours, prognosis was more favourable for single-organ metastasis, except for liver or distant lymph nodes, no residual tumor, and resection of metastasis (median OS: 4.1, 4.6, and 2.6 years, respectively)., Conclusions: In stage IV ovarian carcinoma, non-S/E tumours are associated with a significantly poorer prognosis and higher rates of early mortality compared to S/E tumours. Therefore, careful management and development of new strategies are required.

Objectives: We retrospectively analyzed the clinicopathological features and evaluated the prognostic indicators of recurrence in 132 patients with clear cell adenocarcinoma (CCC) of the ovary at reproductive age., Patients and Methods: Between 1986 and 2011, as a regional population-based study, clinicopathological data on 132 young patients with CCC, collected under the central pathological review system, were subjected to uni- and multivariable analyses to evaluate recurrence-free survival (RFS)., Results: The median age was 40 (27-45) years. The median follow-up period for surviving patients was 46.4 months. During the observation period, there were 16 recurrences in 87 patients with stage I tumors (18.4 %), 8 in 17 with stage II (47.1 %), and 16 in 28 with III-IV (57.1 %). Subsequently, 35 patients died of the disease. Those with stage I or II did not reach the median RFS. The median RFS of stage III-IV was 21.6 months. When analysis was confined to stage I patients, there was no significant difference in the RFS of CCC patients between IA and IC(r) (intraoperative capsule rupture) (P = 0.7957). In contrast, CCC patients with IC excluding IC(r) [IC(non-r)] showed a poorer RFS than those with IC(r) (P < 0.0001). In multivariable analysis confined to stage I patients, the substage group was only an independent prognostic factor for RFS [IA vs. IC(non-r)] [hazard ratio (HR) = 9.394; 95 % CI, 1.445-61.070; P = 0.0190]., Conclusion: We should keep in mind the greater risk of recurrence in patients with stage IC disease or higher, other than those stage IC patients with intraoperative rupture.

Objectives: This study was conducted to estimate the oncologic outcome of stage I epithelial ovarian carcinoma (EOC) patients after recurrence., Study Design: After central pathological review and searching of the medical records of multi-institutions, a total of 103 relapsed patients with stage I EOC were analyzed. The major endpoint was postrecurrence survival (PRS)., Results: The median follow-up for surviving patients was 57.5 (5.7-242.0) months. The median age was 52 (14-89). Among the patients, 19 (18.4%) had FIGO IA disease, and 4 (3.9%) and 80 (77.7%) had IB and IC disease, respectively. Regarding the histological type, the clear-cell type was the most frequently observed (N=42: 40.8%). The 3/5-year overall and PRS rates of all patients were 63.7/47.9 and 38.2/24.0%, respectively. The 5-year PRS rates of patients with serous, endometrioid, clear-cell, and mucinous tumors were 44.9, 35.0, 19.8, and 0%, respectively. On stratifying by the histological type, the overall and postrecurrence survival rates of patients with the mucinous/clear-cell types were significantly poorer than in those with the non-mucinous/clear-cell types (OS: P=0.0253, PRS: P=0.0016). In multivariate analyses, the FIGO stage (IA/IB vs. IC) and histological type (clear-cell/mucinous vs. non- clear-cell/mucinous) retained their significance as prognostic factors of a poorer PRS {stage IC (vs., Ia/b) Hr: 2.176 (95% CI: 1.059-4.470), P=0.0343: clear-cell/mucinous (vs. non- clear-cell/mucinous): HR: 2.486(95% CI: 1.416-4.364), P=0.0015)., Conclusions: Even if at stage I, once patients with a mucinous/clear-cell histology experience recurrence, subsequent survival is extremely poor., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Glypican-3 (GPC3) is specifically expressed in ovarian clear cell carcinoma (OCCC), hepatocellular carci-noma (HCC), and melanoma and lung cancer. GPC3 is being explored as a potential candidate for OCCC and HCC immunotherapy. As a tumor-associated antigen, induction of immune response of GPC3 in ovarian cancer remains elusive. We established a GPC3 transgenic mouse ovarian cancer cell line, OV2944-HM-1 (HM-1), and used the intraperitoneal ovarian cancer mouse model to investigate immune response in GPC3-expressing tumor. We found that GPC3 expression in the tumor increased F4/80+CD86+ macrophage (M1) proportion and caused GPC3-specific CD8+ T cell immune responses, and prolonged mouse survival. Our results demonstrated that GPC3 expression induced T cell-mediated immune response in this mouse ovarian cancer model and also provided supportive evidence that GPC3 is an ideal target for ovarian cancer immunotherapy.

The TGFβ-mediated alteration of the tumor microenvironment plays a crucial role in tumor progression. Mesothelial cells are the primary components of the tumor microenvironment for ovarian cancer cells; however, the exact role of TGFβ-stimulated mesothelial cells in ovarian cancer progression remains uncertain. In this report, we examined the effects of TGFβ-treated mesothelial cells on ovarian cancer progression. We show that TGFβ-stimulated human primary mesothelial cells (HPMC) are able to promote cancer cell attachment and proliferation and the activation of the promoter activities of MMP-2 and MMP-9, which are metalloproteinases necessary for tumor invasion. Expression of the miR200 family was downregulated in HPMCs by TGFβ stimulation, and restoration of the expression of miR200 family members in HPMCs suppressed cancer cell attachment and proliferation. Downregulation of the miR200 family by TGFβ induced fibronectin 1 production, which promoted cancer cell attachment to HPMCs. Finally, we demonstrated that the delivery of the miR200s to mesothelial cells in mice inhibited ovarian cancer cell implantation and dissemination. Our results suggest that alteration of the tumor microenvironment by the miR200 family could be a novel therapeutic strategy for ovarian cancer treatment., (©2014 American Association for Cancer Research.)

Ovarian cancer is the most lethal gynecologic malignancy, and clear cell adenocarcinoma of the ovary (OCCA), in particular, has a relatively poor prognosis among the ovarian cancer subtypes because of its high chemoresistance. Chromobox (CBX) 7 is a polycomb repressive complex 1 component that prolongs the lifespan of normal human cells by downregulating the INK4a/ARF expression which promotes cell-cycle progression. However, recent reports studying the relationship between CBX7 expression and patient survival have differed regarding the tumor cell origins, and the precise role of CBX7 in human carcinomas remains obscure. In this study, we analyzed CBX7 expression by immunohistochemistry in 81 OCCA patients and evaluated its association with their clinical outcomes. Both the overall and progression-free survival rates of the CBX7-positive patients were significantly shorter than those of the CBX7-negative patients (p < 0.05). CBX7 knockdown experiments using two OCCA cell lines, TOV21G and KOC-7C, revealed that cell viability was significantly reduced compared to the control cells (p < 0.001). Expression microarray analysis revealed that apoptosis-related genes, particularly tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), were significantly upregulated in CBX7 knockdown cells (p < 0.01). We further confirmed that CBX7 knockdown resulted in TRAIL-induced apoptosis in the OCCA cells. Thus, in this study, we showed for the first time that CBX7 was associated with a decreased OCCA prognosis. We also successfully demonstrated that the TRAIL pathway is a novel target for CBX7 expression modulation in these cells, and therapeutic agents utilizing the TRAIL pathway may be particularly effective for targeted OCCA therapy., (© 2013 UICC.)

Human REV7 (also known as MAD2L2 and MAD2B) is involved in DNA repair, cell cycle regulation, gene transcription, and carcinogenesis. In this study, we evaluated the expression of REV7 in epithelial ovarian cancer (EOC) and analyzed the association between its expression and chemosensitivity in ovarian clear cell carcinoma (CCC) cells. Expression of REV7 in human EOC tissues was assessed by immunohistochemical staining. Expression was detected in the majority of EOCs (92.0%) with especially high levels of expression frequently observed in CCCs (73.5%) compared with that of non-CCCs (53.4%). Enhanced immunoreactivity to REV7 was associated with poor prognosis represented by reduced progression-free survival in advanced stage (stage II-IV) EOC as assessed using Kaplan-Meier curves and log-rank tests. The effects of REV7 knockdown on cell proliferation and chemosensitivity in CCC cells were also analyzed in vitro and in vivo. Knockdown of REV7 in CCC cells decreased cell proliferation without affecting cell cycle distribution. Additionally, the number of apoptotic cells and DNA damaged cells were increased after cisplatin treatment. In a nude mouse tumor xenograft model, inoculated REV7-knockdown tumors showed significantly reduced tumor volumes after cisplatin treatment compared with those of the control group. These findings indicate that depletion of REV7 enhances sensitivity to cisplatin treatment in CCC, suggesting that REV7 is a candidate molecular target in CCC management., (© 2014 The Authors. Cancer Science published by Wiley Publishing Asia Pty Ltd on behalf of Japanese Cancer Association.)

Objectives: We reviewed the clinical outcomes of patients with early-stage epithelial ovarian cancer (EOC) who had undergone fertility-sparing surgery (FSS) to assess recurrence-free survival (RFS)., Study Design: After central pathological review and scanning of the medical records of multiple institutions, a total of 94 patients with stage I EOC (IA: 43 and IC: 51) treated with FSS were analyzed. IC substages were defined as follows: intraoperative spillage (IC1), preoperative capsule rupture or surface invasion (IC2), and positive cytology results (IC3)., Results: The median age was 30.5 (13-40) years. The median follow-up time was 66.6 months. Fourteen patients (14.9%) showed carcinoma recurrence. Eleven (11.7%) patients died of the disease. The total 5-year RFS rate including all women who received FSS was 84.3%. There was no significant difference in RFS between patients with IC1 and those with stage IA (P=0.9411). In contrast, the RFS rate of patients with IC2/3 was significantly poorer than in patients with stage IA (IA vs. IC2/3: P=0.0487, IC1 vs. IC2/3: P=0.0471). In further analyses according to each histological type and grade, the RFS rate of subjects with the mucinous type was the same as that of those with a clear-cell histology (P=0.3350). There was a significant difference in RFS of patients with grade 1 (G1) and G2-3 (P=0.0004). To eliminate selection bias from a number of clinicopathologic factors as thoroughly as possible, the age, FIGO stage, histological type, grade, and postoperative adjuvant chemotherapy were entered into multivariate RFS analyses. Cox multivariable analysis showed that the substage group and grade were independent prognostic factors for RFS., Conclusions: Confined to young women with intraoperative rupture, FSS may be proposed, if without tumor-associated dense adhesion. However, those with preoperative rupture, surface invasion, and positive cytology showed a greater risk of recurrence, suggesting that they are not recommended candidates. Although patients with G2-3 tumors showed a poorer prognosis than those with G1, the number of these subjects was so small that the current results should be reconfirmed in the next study., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Background: This study was conducted to assess the long-term clinical outcome for patients with recurrent mucinous epithelial ovarian cancer (RmOC) in comparison with recurrent serous epithelial ovarian cancer (RsOC)., Methods: Three hundred and eighty-four patients with recurrent ovarian cancer, including 340 RsOC and 44 RmOC patients, were analyzed in this study. The pathological slides were evaluated under central pathological review. The prognostic significance of clinicopathological factors was evaluated employing both uni- and multivariable analysis., Results: The 3- and 5-year postrecurrence survival (PRS) rates of patients with RmOC were 17.3, and 6.9 %, respectively. In contrast, those of patients with RsOC were 29.8 and 18.8 %, respectively. The PRS of patients with RmOC was significantly poorer than that of patients with RsOC (PRS: P = 0.0006). Moreover, either in the presence or absence of a residual tumor (RT) at initial surgery, the PRS of patients with RmOC was markedly poorer than that of patients with RsOC [RT (-): P < 0.0001: RT (+): P = 0.0912]. In multivariable analysis, a mucinous histology predicted a significantly poorer PRS (RmOC vs. RsOC: hazard ratio (HR) 2.080, 95 % confidence interval (CI) 1.434-3.016, P = 0.0001). Confining analysis to deceased patients (N = 302), the proportion of RmOC patients who died within 12 months following recurrence was markedly higher than that of RsOC [RmOC 69.2 %, RsOC: 41.1 % (P < 0.0001)]., Conclusions: The clinical outcome after recurrence in patients with RmOC was extremely poor. This confirms that RmOC should be considered a different entity from other epithelial ovarian cancers.

Carcinoembryonic antigen glypican-3 (GPC3) is expressed by>40% of ovarian clear cell carcinoma (CCC) and is a promising immunotherapeutic target. We previously reported the safety of and immunological and clinical responses to a GPC3-derived peptide vaccine in a phase I clinical trial of patients with advanced hepatocellular carcinoma (HCC). Although the efficacy of the GPC3-derived peptide vaccine against HCC patients was evaluated, other GPC3-positive cancer patients have not yet been investigated. Therefore, we conducted a phase II trial to evaluate the clinical outcome of ovarian CCC patients treated with a GPC3-derived peptide vaccine. The GPC3 peptide was administered at a dose of 3 mg per body. Patients received an intradermal injection of the GPC3 peptide emulsified with incomplete Freund's adjuvant. Vaccinations were performed biweekly from the first until the 6th injection and were then repeated at 6-week intervals after the 7th injection. Treatment continued until disease progression. We herein present two patients with chemotherapy-refractory ovarian CCC who achieved a significant clinical response in an ongoing trial of a GPC3 peptide vaccine. Case 1, a 42-year-old patient with advanced recurrent ovarian CCC with liver and retroperitoneal lymph node metastases, received the HLA-A24-restricted GPC3 peptide vaccine. Contrast-enhanced CT at week 10 revealed a partial response (PR) using RECIST criteria. Case 2 was a 67-year-old female with multiple lymph node metastases. She was injected with the HLA-A2-restricted GPC3 peptide vaccine. According to RECIST, PR was achieved at week 37. The stabilization of their diseases over one year provided us with the first clinical evidence to demonstrate that GPC3 peptide-based immunotherapy may significantly prolong the overall survival of patients with refractory ovarian CCC.

In an attempt to induce cytotoxic T lymphocytes (CTLs) that react to ovarian cancer cells, we isolated a CTL clone that specifically recognizes claudin-1 in an HLA-A*24:02-restricted manner. Naïve CD8(+) T lymphocytes were obtained from a healthy adult donor and stimulated twice in vitro with HLA-modified TOV21G cells that were originally derived from an ovarian clear-cell carcinoma line. The TOV21G modification involved RNAi-mediated gene silencing of intrinsic HLA molecules and lentiviral transduction of a synonymously mutated HLA-A*24:02. Then, cDNA library construction using mRNA extracted from the parental TOV21G cells and subsequent expression cloning were conducted. These experiments revealed that a CTL clone obtained from the bulk culture recognized a minimal epitope peptide RYEFGQALF, which was derived from an autoantigen claudin-1 presented by HLA-A*24:02 molecules. This clone exhibited cytolytic activities against three ovarian cancer cell lines and normal bronchial epithelial cells in an HLA-A*24:02-restricted manner. Our data indicate that HLA-modified cancer cells can be used as an artificial antigen-presenting cell to generate antigen-specific CTLs in a manner restricted by an HLA allele of interest., (Copyright © 2013 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.)

With proper and careful selection of patients, fertility-preserving surgery may be feasible in patients with ovarian malignancies. However, the loss of follicles by oophorectomy and chemotherapy results in decreased ovarian reserve, which consecutively affects reproductive capacity. We evaluated postoperative levels of serum anti-Müllerian hormone (AMH) in women with ovarian malignancies to assess the impact of the fertility-preserving surgery with or without the administration of chemotherapy on ovarian reserve. In 13 patients who underwent the fertility-preserving surgery with (n = 9) or without (n = 4) the administration of chemotherapy, serum AMH levels were measured and compared with serum AMH levels measured in patients undergone cystectomy for benign ovarian tumors as a control. We found that the mean AMH level in the treatment group measured 0.9 ng/mL, which was significantly lower than that measured in the control group (4.70 ± 3.77 ng/mL). The possibility of decreased ovarian reserve occurring in patients with ovarian malignancies following treatment with fertility-preserving surgery with or without the administration of chemotherapy should be considered for fertility planning.

Ovarian cancer is a highly invasive and metastatic disease with a poor prognosis if diagnosed at an advanced stage, which is often the case. Recent studies argue that ovarian cancer cells that have undergone epithelial-to-mesenchymal transition (EMT) acquire aggressive malignant properties, but the relevant molecular mechanisms in this setting are not well-understood. Here, we report findings from an siRNA screen that identified the homeobox transcription factor ALX1 as a novel regulator of EMT. RNA interference-mediated attenuation of ALX1 expression restored E-cadherin expression and cell-cell junction formation in ovarian cancer cells, suppressing cell invasion, anchorage-independent growth, and tumor formation. Conversely, enforced expression of ALX1 in ovarian cancer cells or nontumorigenic epithelial cells induced EMT. We found that ALX1 upregulated expression of the key EMT regulator Snail (SNAI1) and that it mediated EMT activation and cell invasion by ALX1. Our results define the ALX1/Snail axis as a novel EMT pathway that mediates cancer invasion., (©2012 AACR.)

Resistance to platinum- and taxane-based chemotherapy is a major cause of treatment failure in ovarian cancer. Thus, it is necessary to develop a predictive marker and molecular target for overcoming drug resistance in ovarian cancer treatment. In a previous report, using an in vitro model, we found that the RET finger protein (RFP) (also known as tripartite motif-containing protein 27, TRIM27) confers cancer cell resistance to anticancer drugs. However, the significance of RFP expression in cancer patients remains elusive. In this study, we showed that RFP was expressed in 62% of ovarian cancer patients and its positivity significantly correlated with drug resistance. Consistent with clinical data, depletion of RFP by RNA interference (RNAi) in ovarian cancer cell lines, SKOV3 and HEY, significantly increased carboplatin- or paclitaxel-induced apoptosis and resulted in reduced anticancer drug resistance. In a nude mouse tumor xenograft model, inoculated RFP-knockdown ovarian cancer cells exhibited lower carboplatin resistance than control cells. These findings suggest that RFP could be a predictive marker for chemoresistance in ovarian cancer patients and also a candidate for a molecular-targeted agent.

Background: It is controversial whether patients with stage I ovarian clear cell carcinoma (CCC) benefit from postoperative chemotherapy. This study was designed to evaluate the postoperative outcomes associated with the inclusion or exclusion of adjuvant therapy in these patients., Methods: A total of 185 patients who were treated for stage I CCC between 1991 and 2007 were retrospectively evaluated. All of the patients had received comprehensive surgical staging, and their condition had been diagnosed by a central pathological review system. Only one patient with stage IB was excluded from this study., Results: Median follow-up time was 62 months (range 7-191 months). Median age was 52 years (30-75 years). There were 41, 93, and 50 patients in stage IA, intraoperative capsule ruptured IC (rupture-IC), and all other-IC groups, respectively. The 5-year recurrence-free survival rates for the substage were 97.6%, 87.8%, and 70.4% (P < 0.001), respectively. Among 134 patients consisting of those in the stage IA and rupture-IC groups, 91 patients received adjuvant chemotherapy (AC) and 43 patients did not (non-AC). There was no significant survival difference in each substage group between the non-AC and AC groups in 5-year recurrence-free survival rate (stage IA, 100% vs 93.8%; rupture-IC, 94.1% vs 86.6%). Multivariate analysis demonstrated that there was no significant prognostic factor for both recurrence and survival among the IA and rupture-IC groups. Postoperative therapy, regimen, and chemotherapy cycles were not significantly affected., Conclusions: This study indicates that adjuvant chemotherapy does not contribute to the improving prognosis of stage IA ovarian CCC. Whereas the histological type is CCC, the routine adjuvant chemotherapy after comprehensive surgical staging may be unnecessary for patients with at least stage IA.

Aim: The effect of systematic retroperitoneal lymphadenectomy (SRL) remains controversial in patients with advanced epithelial ovarian cancer (aEOC) who are optimally debulked., Material and Methods: Demographic and clinicopathologic data were obtained from the Tokai Ovarian Tumor Study Group between 1986 and 2009. All patients were divided into two groups. Group A (n = 93): (i) patients did not undergo SRL; and (ii) lymph node exploration or sampling was optional. Group B (n = 87): patients underwent SRL. Survival curves were calculated using the Kaplan-Meier method. Differences in survival rates were analyzed using the log-rank test., Results: All pT3-4 aEOC patients were optimally debulked (residual tumor <1 cm). The median age was 55 years (range: 18-84). The 5-year progression-free survival (PFS) rates of groups A and B were 46.7 and 41.9%, respectively (P = 0.658). In addition, the 5-year overall survival (OS) rates were 62.9 and 59.0%, respectively (P = 0.853). Subsequently, there was no significant difference in OS and PFS in the two groups stratified to histological type (serous or non-serous type). Furthermore, there was no significant difference in recurrence rates in retroperitoneal lymph nodes regardless of completion of lymphadenectomy., Conclusion: Our data suggest that aEOC patients with optimal cytoreduction who underwent SRL did not show a significant improvement in survival irrespective of each histological type., (© 2012 The Authors. Journal of Obstetrics and Gynaecology Research © 2012 Japan Society of Obstetrics and Gynecology.)

Recent reports have shown that CXCR4 is expressed in various solid tumors and is involved in tumor development and metastasis. We examined the distribution and expression of this molecule in clear cell carcinoma of the ovary to elucidate its clinical significance. Paraffin sections from clear cell carcinoma of the ovary tissues (n = 42) were immunostained with CXCR4 antibody, and the staining intensities were evaluated. The clinicopathologic factors examined were age, FIGO (International Federation of Gynecology and Obstetrics) staging, preoperative value of cancer antigen 125 test, and residual tumor after cytoreductive surgery. Overall survival and progression-free survival were evaluated using the Kaplan-Meier method, and multivariate analysis was completed using Cox proportional hazards analysis. Of the 42 carcinomas, lower level CXCR4 immunoexpression was observed in 21 cases (50.0%) (CXCR4(low) group); and higher level immunoexpression, in 21 cases (50.0%) (CXCR4(high) group). Five-year overall survival was significantly poorer in the CXCR4(high) group than in the CXCR4(low) group (overall survival, CXCR4(low) group [90.2%], CXCR4(high) group [50.3%]; P = .0002). In addition, CXCR4(high) immunoexpression significantly predicted a poorer progression-free survival when compared with lower expression (5-year progression-free survival, CXCR4(low) group [90.5%], CXCR4(high) group [36.2%]; P < .0001). Furthermore, multivariate analyses including the age, preoperative cancer antigen 125 test value, FIGO stage, and CXCR4 expressions revealed that CXCR4(high) expression was an independent prognostic factor for poorer overall survival and progression-free survival of patients with clear cell carcinoma of the ovary (overall survival, P = .0011; progression-free survival, P = .0008, respectively). Our current study suggested that the assessment of CXCR4 immunoreactivity may be a useful prognostic indicator and that CXCR4 may play a critical role in the progression of clear cell carcinoma of the ovary., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Objectives: To estimate the long-term clinical outcome of patients with recurrent clear cell carcinoma (RCCC) of the ovary in comparison with those with recurrent serous adenocarcinoma (RSAC)., Patients and Methods: In this study, 113 patients with RCCC and 365 patients with RSAC were analyzed. The pathological slides were evaluated under central pathological review. End points were the overall survival (OS), postrecurrence survival (PRS), and timing of death of mortality cases., Results: The 5-year OS and PRS rates of patients with RCCC were 22.5 and 13.2%, respectively. In both OS and PRS, the prognosis of patients with RCCC was significantly poorer than that of the patients with RSAC (OS: P = 0.0007; PRS: P < 0.0001). Moreover, regardless of the status of the residual tumor (RT) at the initial surgery, the OS and PRS of the patients with RCCC were markedly shorter than those with RSAC (RT [-]: OS, P = 0.0005: PRS, P = 0.0002: RT [+]: OS, P < 0.0001: PRS, P < 0.0001). In multivariable analysis, the histological type was a significantly poorer prognostic indicator for OS and PRS (OS [RCCC vs RSAC]: hazard ratio, 2.302: 95% confidence interval, 1.723-3.076; P < 0.0001: PRS [RCCC vs RSAC]; hazard ratio, 2.353: 95% confidence interval, 1.756-3.155; P < 0.0001). Even in the deceased patients (n = 350), the rate of patients with RCCC dying within 12 months of recurrence was higher than that of RSAC (RCCC, 67.8%; RSAC, 40.7%; [P < 0.0001])., Conclusions: The long-term clinical outcome of patients with RCCC was extremely poor. We confirmed that RCCC should be investigated as a different malignancy compared with RSAC.

Aim: Primary ovarian malignant germ cell tumors (OMGCTs) are rare and difficult to diagnose. Immunohistochemistry can help in the diagnosis and development of new management strategies. The aim of this study was to investigate the frequency of CD117, CD133, SALL4, OCT4, TCL1 and glypican-3 marker expression in OMGCTs., Material and Methods: We examined the expression of six markers in 87 (85 pure and two mixed OMGCTs) cases of OMGCT using immunohistochemical staining. Staining was graded in a semiquantitative manner as follows: negative (no staining), 1+ (1-30% staining), 2+ (31-60% staining), or 3+ (>60% staining)., Results: All 27 dysgerminomas and all 31 YSTs showed CD117 expression, with only nine (29%) positively stained in immature teratomas. SALL4 and glypican-3 were strongly positive in 100 and 79.3%, respectively, of YSTs. All dysgerminomas were positive for OCT4, whereas all YSTs and immature teratomas were negative. 100% of dysgerminomas were positive for TCL1, but all immature teratomas were negative. CD133 expression showed generally the same tendency in the 3 OMGCTs., Conclusion: CD117 can be used as a diagnostic marker for dysgerminoma and YST. SALL4 is a more sensitive and specific marker for YSTs than glypican-3. SALL4 and OCT4 are useful in distinguishing YST from dysgerminoma., (© 2012 The Authors. Journal of Obstetrics and Gynaecology Research © 2012 Japan Society of Obstetrics and Gynecology.)

Objective: This study was conducted to estimate the long-term clinical outcome of patients with recurrent ovarian carcinoma (ROC)., Methods: Six hundred three patients with ROC were analyzed in this study. The pathological slides were evaluated under central pathological review. The prognostic significances of clinicopathologic factors were evaluated using both univariate and multivariate analysis., Results: The 5-year overall survival (OS) and postrecurrence survival (PRS) rates were 31.1 and 16.9%, respectively. On stratifying to treatment periods, the PRS has been prolonged over the last decade (year ≥2000) compared with before this period (year ≤1999) (P = 0.0002). In contrast, on stratifying to histological types and treatment periods, in both OS and PRS, the prognosis of patients with the nonmucinous/clear-cell histology, including serous, endometrioid, and other histological types, was significantly improved after 2000 compared with before (year ≤1999) (OS, P = 0.0009; PRS, P < 0.0001). In contrast, that of patients with the mucinous/clear-cell histology did not significantly differ regardless of the treatment period (≥2000 vs ≤1999: OS, P = 0.3887; PRS, P = 0.7617). In multivariate analysis, the stage, period of starting initial treatment, histological type, and the treatment-free interval were independent prognostic factors of a poor OS and PRS (OS/PRS: histological type: mucinous/clear-cell vs nonmucinous/clear-cell: hazard ratio, 1.300/1.498; 95% confidence interval [CI], 1.039-1.626/1.197-1.874)., Conclusions: Despite the continuous administration of treatment for ROC, survival is poor, and the extent of therapeutic progress differs according to the histological type.

Objective: In recent years it has been indicated that ecological niches play important roles in the maintenance of cancer stem cells (CSCs). We investigated interactions between peritoneal mesothelial cells and SC-OYST based on the hypothesis that peritoneal mesothelial cells have the potential to provide one of the niches for SC-OYST., Methods: We divided NOY1 cells into CD133-positive and -negative cells. Using the co-culture of NOY1 and peritoneal mesothelial cells, we compared the expression of CD133, colony formation, and the capacity for migration and invasion. In addition, we assessed the inhibitory effects of AMD3100, a neutralizing antibody against a chemokine receptor (CXCR4). Then, we examined whether AMD3100 affects the tumorigenicity of NOY1-CD133+ cells in vivo., Results: When NOY1 cells were co-cultured with peritoneal mesothelial cells, we observed the high-level expression of CD133. The number of colonies of NOY1-CD133+ cells was 2.4 times that of NOY1-CD133- cells. In contrast, on co-culture with peritoneal mesothelial cells, it was 4.3 times. When NOY1 cells were cultivated in the upper layer and peritoneal mesothelial cells were cultivated in the lower chamber, NOY1-CD133+ cells showed a greater capacity for migration and invasion than NOY1-CD133- cells. By adding AMD3100 to the co-culture systems, the colony formation, migration, and invasion of NOY1-CD133+ cells were inhibited. In addition, AMD3100 inhibited the tumorigenicity of NOY1-CD133+ cells in vivo., Conclusions: Our data suggest that peritoneal mesothelial cells have the potential to provide one of the niches for NOY1 cells. Investigation of the niches of SC-OYST will help elucidate important targets for therapeutic approaches., (Copyright © 2011 Elsevier Inc. All rights reserved.)

To overcome drug resistance in ovarian carcinoma, novel resistance mechanisms must be elucidated for clinical application. We purified 2 proteins in the 300 kDa range from cisplatin-resistant cells (NOS2CR2) by affinity chromatography with cisplatin-exposed Glutathione Sepharose 4B. The purified proteins were identified as spectrin αII and βII by peptide mass mapping analysis. Western blot analysis detected greater expression of spectrin αII and βII in NOS2CR2 than in wild-type cells (NOS2). The same result was obtained for spectrin βII expression by immunohistochemical staining. To determine whether spectrin αII and βII contribute to resistance, a drug sensitivity test was performed on SKOV3 ovarian cancer cells transfected with small interfering RNA. Sensitivity to platinum drugs was increased in the expression reduced cells. In a clinical study of five ovarian serous adenocarcinoma cases, tumor specimens taken after treatment with carboplatin stained more strongly for spectrin βII expression than untreated specimens. Fifty-two tumor specimens from 46 patients with ovarian serous adenocarcinoma were immunohistochemically stained for spectrin βII and scored. Tumors previously treated by chemotherapy scored higher than those not treated. Of 27 cases with detectable residual tumors at the time of surgery, cases scoring 4-6 had shorter progression-free survival periods after platinum-based chemotherapy than cases scoring 0-3 (p = 0.012). The cytoskeleton proteins Spectrin αII and βII contributed to drug resistance by anchoring the GS-Pt complex to the cell membrane, arresting cisplatin activity. Thus spectrin βII may be a useful predictor of platinum sensitivity in ovarian serous adenocarcinoma., (Copyright © 2011 UICC.)

Background: Clear-cell carcinoma of the ovary (CCC) is often diagnosed at childbearing age, or sometimes during treatment for infertility. Therefore, most young women with early-stage CCC wish to preserve their reproductive and endocrine functions if possible., Methods: Clinicopathologic data collected under the central pathological review system were subjected to survival analyses. We analyzed patients with stage I CCC who underwent fertility-sparing surgery (FSS, n = 16) and compared their long-term survival with those receiving radical surgery (n = 205), or patients with non-CCC undergoing FSS (n = 64)., Results: There was no difference in both the overall survival (OS) and disease-free survival (DFS) between patients with CCC who underwent FSS and those who received radical surgery [CCC/FSS (n = 16) versus CCC/radical (n = 205); OS: P= 0.519, DFS: P= 0.265]. Moreover, patients with CCC who underwent FSS did not show a poorer OS and DFS than non-CCC patients who underwent FSS (CCC/FSS versus non-CCC/FSS; OS: P= 0.584, DFS: P= 0.401), or those at the corresponding stage with no CCC. Furthermore, according to the series of patients with CCC in both the current study and four studies in the literature, there was no difference in the recurrence rate between patients with or without CCC who were treated conservatively (CCC/FSS: 13.2% versus non-CCC/FSS: 10.9%, P= 0.614)., Conclusions: Although our study did not have sufficient power to yield a definite conclusion, our data suggests that at least patients with stage IA CCC may be treated with FSS.

Objective: We analyzed a large number of stage I clear cell carcinoma of the ovary (CCC) patients to estimate the survival impact of the capsule status in stage I CCC patients, particularly in comparison with non-CCC patients., Methods: Clinicopathologic data on 564 patients with stage I epithelial ovarian cancer (EOC) collected under the central pathological review system were subjected to uni- and multivariable analyses to evaluate the disease-free survival (DFS) and overall survival (OS)., Results: There was no significant difference in both the OS and DFS of CCC patients between IA and IC(ir) (intraoperative capsule rupture) {IA vs. IC(ir); OS: P=0.1402, DFS: P=0.2701}. In contrast, CCC patients at IC(non-ir) {IC excluding for IC(ir), such as preoperative capsule rupture, positive ascites/washing, and surface involvement} showed a poorer OS and DFS than those at IC(ir), or those at the corresponding stage in non-CCC. In multivariable analysis, the capsule status was an independent prognostic factor of a poor OS and DFS {OS: HR, 2.832; 95% CI 1.156-6.938; P=0.023; DFS: HR, 4.327; 95% CI, 1.937-9.667; P=0.0004)} {In contrast, non-CCC: N.S. (OS/DFS)}. Furthermore, in CCC patients, intraperitoneal recurrences were more frequently observed in IC(non-ir) CCC than IA or IC(ir) CCC (P=0.0083) {In contrast, non-CCC: N.S.}., Conclusion: This study suggests that CCC patients other than those with intraoperative capsule rupture show a considerable risk for mortality despite adjuvant chemotherapy., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Objectives: To compare the clinical outcome of patients with stage I epithelial ovarian cancer (EOC) who received with fertility-sparing surgery (FSS) with those who underwent radical surgery (RS)., Methods: After a central pathological review and search of the medical records from multiple institutions, a total of 572 patients were retrospectively evaluated. All patients were divided into three groups: group A {FSS (n=74); age, ≤ 40}; groups B and C [RS; age, 40 ≥{(B), n=52}; 40<{(C), n=446}]., Results: Five-year overall survival (OS) and disease-free survival (DFS) rates of patients in the groups were as follows: group A, 90.8% (OS)/87.9% (DFS); group B, 88.3% (OS)/84.4% (DFS); group C, 90.6% (OS)/85.3% (DFS), respectively (OS, P=0.802; DFS, P=0.765). Additionally, there was no significant difference in OS and DFS among the three groups stratified to stage IA or IC (OS (IA), P=0.387; DFS (IA), P=0.314; OS (IC), P=0.993; DFS (IC), P=0.990, respectively). Furthermore, patients with a grade 1-2 or 3 tumours in the FSS group did not have a poorer prognosis than those in the RS group., Conclusions: Stage I EOC patients treated with FSS showed an acceptable prognosis compared with those who underwent RS.