Yoshihiro J. Ono

Hepatocyte growth factor secreted by ovarian cancer cells stimulates peritoneal implantation via the mesothelial-mesenchymal transition of the peritoneum.

OBJECTIVE A current working model for the metastatic process of ovarian carcinoma suggests that cancer cells are shed from the ovarian tumor into the peritoneal cavity and attach to the layer of mesothelial cells that line the inner surface of the peritoneum, and several studies suggest that hepatocyte growth factor (HGF) plays an important role in the dissemination of ovarian cancer. Our objectives were to evaluate the HGF expression of ovarian cancer using clinical data and assess the effect of HGF secreted from human ovarian cancer cells to human mesothelial cells. METHODS HGF expression was immunohistochemically evaluated in 165 epithelial ovarian cancer patients arranged as tissue microarrays. HGF expression in four ovarian cancer cell lines was evaluated by using semi-quantitative polymerase chain reaction, Western blotting and enzyme-linked immunosorbent assay. The effect of ovarian cancer cell derived HGF to the human mesothelial cells was assessed by using morphologic analysis, Western blotting and cell invasion assay. The effect of HGF on ovarian cancer metastasis was assessed by using in vivo experimental model. RESULTS The clinical data showed a significantly high correlation between the HGF expression and the cancer stage. The in vivo and in vitro experimental models revealed that HGF secreted by ovarian cancer cells induces the mesothelial-to-mesenchymal transition and stimulates the invasion of mesothelial cells. Furthermore, manipulating the HGF activity affected the degree of dissemination and ascite formation. CONCLUSIONS We demonstrated that HGF secreted by ovarian cancer cells plays an important role in cancer peritoneal implantation.

Estradiol-mediated hepatocyte growth factor is involved in the implantation of endometriotic cells via the mesothelial-to-mesenchymal transition in the peritoneum

The pathogenesis of endometriosis, a chronic painful gynecological disease characterized by the presence of endometrial tissue located outside of the uterus and often adhering to the peritoneum, is known to be estrogen dependent. However, the precise pathophysiology of endometriosis remains elusive. Recent studies indicate that the epithelial-to-mesenchymal transition (EMT) of human endometrial cells is important for the progression of endometriosis, and another previous study has implicated hepatocyte growth factor (HGF) in endometriosis progression. The aim of the present study was to examine the role of estradiol in the regulation of HGF production and progression of peritoneal endometriosis, focusing on the interactions between the peritoneum and endometriotic cells. Consequently, estradiol was found to promote the proliferation, invasion, and migration of immortalized human endometrial epithelial cells (hEECs) via HGF upregulation, and the estradiol-induced direct binding of estrogen receptor-α to the HGF promoter was confirmed on a chromatin immunoprecipitation (ChIP) assay. Estradiol also induced the EMT in hEECs by promoting HGF production. Furthermore, human mesothelial cells underwent the mesothelial-to-mesenchymal transition (MMT) during culture with estradiol-stimulated hEEC conditioned medium. Importantly, estradiol itself did not induce the MMT, and the estradiol-stimulated hEEC-conditioned medium in the presence of HGF antibodies reversed the MMT process. These results, which were obtained using immortalized hEECs, indicate that estradiol-induced HGF production may play a crucial role in the peritoneal implantation of human endometriotic cells by exerting proliferative and invasive effects via the EMT in hEECs and promoting the MMT in mesothelial cells.

Analyzing the possible involvement of anti-Müllerian hormone and anti-Müllerian hormone receptor II single nucleotide polymorphism in infertility

PurposeWe performed TaqMan genotyping assays of anti-Mullerian hormone (AMH) and anti-Mullerian hormone receptor type II (AMHRII) single nucleotide polymorphisms (SNPs) in order to investigate how their frequency and distribution affect infertility treatment outcome.MethodsEighty Japanese women (advanced age: n = 51, endometriosis: n = 18, male infertility as a control: n = 11) who undertook ART were included in the study, and all couples underwent a full infertility investigation protocol. In order to investigate the natural distribution of SNPs, a naturally pregnant group of 28 subjects was recruited from among women who conceived naturally and subsequently delivered in our department. Genomic DNA was extracted from peripheral blood and genotyping was conducted by TaqMan genotyping assay. The relationship of AMH and AMHRII SNPs and treatment outcome in infertile women. Comparison of allele and genotype frequencies of infertile patients with naturally pregnant women.ResultsAMHRII −482 A>G homozygote mutation was complicated with ISV 5–6 C>T homozygote mutation and showed a significantly lower oocyte retrieval rate compared with a wild type. Two of 3 cases of AMHRII −482 A>G homozygote mutation were poor responders, and the distribution and frequency of each allele of naturally pregnant women showed no statistical difference compared with infertile women.ConclusionsThis study revealed the possible involvement of AMHRII −482 A>G polymorphism on the malfunction of follicular development in Japanese women.

Preoperative MRI and intraoperative frozen section diagnosis of myometrial invasion in patients with endometrial cancer.

Objective The rate of lymph node metastasis is extremely low in patients with low-risk endometrial cancer; lymphadenectomy may be unnecessary for these patients under an accurate preoperative diagnosis. The aim of this study was to evaluate the diagnostic accuracy of myometrial invasion (MI) on preoperative magnetic resonance imaging (MRI) and intraoperative frozen sections (FSs). Materials and Methods Endometrial cancer was diagnosed in a total of 378 patients by preoperative endometrial curettage, preoperative magnetic resonance imaging MRI, and intraoperative FSs; the 378 patients underwent hysterectomy. The depth of MI was evaluated between the preoperative MRI, intraoperative FSs, and final paraffin sections (PSs). The histologic grade was also evaluated between preoperative endometrial curettage, intraoperative FSs, and final PSs. Results The sensitivity, specificity, positive predictive value, and negative predictive value for deep MI (≥50%) on MRI were 57.8%, 92.0%, 69.3%, and 87.5%, respectively, with a kappa value of 0.53. These figures on FSs were 66.7%, 97.9%, 90.9%, and 90.4%, with a kappa value of 0.71. When grade 3 endometrioid adenocarcinoma, serous carcinoma, clear cell carcinoma, and carcinosarcoma were considered high-grade tumors, the grade evaluation at the time of FSs was 70.2%, 99.0%, 96.1%, and 89.7%, with a kappa value of 0.75. In the patients with low-grade tumors, including grade 1 or 2 endometrioid adenocarcinoma on preoperative endometrial curettage, the rate of unexpected lymph node metastasis did not differ significantly between the patients who had a diagnosis of MI and lymph node metastasis by MRI and those with diagnosis of MI and histological grade by FSs (4.0% vs 2.6%; P > 0.05). Conclusions Frozen sections had a higher agreement rate for MI than MRI; however, MRI is still considered an acceptable modality to guide preoperative decisions regarding lymphadenectomy especially in grade 1 or 2 endometrioid adenocarcinoma.

CD24 expression is a marker for predicting clinical outcome and regulates the epithelial-mesenchymal transition in ovarian cancer via both the Akt and ERK pathways

The degree of peritoneal dissemination and chemotherapy-resistant tumors is related to the prognosis in patients with advanced-stage ovarian cancer. The epithelial-mesenchymal-transition (EMT) is a multifaceted pathological program that endows cancer cells with the ability to invade and disseminate. CD24 is frequently overexpressed in various human cancers and is correlated with a poor prognosis. We herein examined the functions of CD24 in human ovarian cancer cell lines and evaluated how it contributes to the molecular mechanism underlying the regeneration of cancer stem-like cells (CSCs) through the EMT mechanism in ovarian carcinoma. We demonstrated that CD24 was expressed in 70.1% of primary ovarian carcinoma tissues, which were obtained from 174 patients, and that the expression of CD24 was an independent predictor of survival in patients with ovarian cancer. The expression of CD24 has been found to be correlated with the FIGO stage, presence of peritoneal and lymph node metastasis. CD24 induces the EMT phenomenon, which is involved in cell invasion, the highly proliferative phenotype, colony formation and which is associated with cisplatin resistance and the properties of CSCs, via the activation of PI3K/Akt, NF-κB and ERK in Caov-3 cisplatin-resistant cell lines. CD24-positive ovarian carcinomas have been shown to have a greater potential for intra-abdominal tumor cell dissemination in in vivo models. Our findings suggest that CD24 induced the EMT phenomenon in ovarian cancer, and that CD24 amplified cell growth-related intracellular signaling via the PI3K/Akt and MAPK pathways by affecting the EMT signal pathways. We believe that CD24 is a key molecule of metastatic progression in the EMT phenomenon and a promising therapeutic target for advanced ovarian cancer.

A Low-Testosterone State Associated with Endometrioma Leads to the Apoptosis of Granulosa Cells

Although endometriosis is suspected to be a cause of premature ovarian insufficiency (POI), the mechanism(s) underlying this process have not been elucidated. Recently, androgens were shown to promote oocyte maturation and to play a role in folliculogenesis. In addition, several reports have documented low testosterone levels in the follicular fluid obtained from endometriosis patients. We therefore examined whether the low levels of serum testosterone are associated with the apoptosis of granulosa cells in follicles obtained from endometriosis patients. Serum samples were collected from 46 patients with endometriosis and from 62 patients without endometriosis who received assisted reproductive therapy. Specimens of the ovaries obtained from 10 patients with endometrioma were collected using laparoscopy. The mean serum testosterone concentration in the patients with endometriosis was significantly lower than that observed in the patients without endometriosis. Furthermore, high expression of a pro-apoptotic Bcl-2 member, BimEL, in the follicles was found to be associated with a low serum testosterone level. We clarified the underlying mechanisms using a basic approach employing human immortalized granulosa cells derived from a primary human granulosa cell tumor, the COV434 cell line. The in vitro examination demonstrated that testosterone inhibited apoptosis induced by sex steroids depletion via the PI3K/Akt-FoxO3a pathway in the COV434 cells. In conclusion, we elucidated the mechanism underlying the anti-apoptotic effects of testosterone on granulosa cells, and found that a low-testosterone status is a potentially important step in the development of premature ovarian insufficiency in patients with endometriosis.

Met Signaling Cascade Is Amplified by the Recruitment of Phosphorylated Met to Lipid Rafts via CD24 and Leads to Drug Resistance in Endometrial Cancer Cell Lines

Endometrial cancer is the most prevalent gynecologic cancer in the Western world, and the number of advanced chemotherapy-resistant cancers is increasing with the absolute increase in patients. The development of resistance to chemotherapeutic drugs by cancer cells represents a major challenge in the clinical cure of advanced and metastatic cancers. CD24 has been reported to be a marker for a poor prognosis in several tumors, and we herein examined the functions of CD24 in human endometrioid adenocarcinoma cell lines and evaluated how it contributes to cancer drug resistance. We demonstrated that CD24 was responsible for the recruitment of phosphorylated Met to the lipid raft domain of the cell membrane, resulting in amplification of the Met signaling cascade, ultimately leading endometrial cancer cells to express higher levels of ATP-binding cassette (ABC) transporters. Our findings suggest that CD24-mediated amplification of the Met cascade may contribute to the drug resistance of endometrial cancer. Mol Cancer Ther; 14(10); 2353–63. ©2015 AACR.

Postmenopausal patients with endometrial cancer of type 1 have elevated serum estradiol levels in the ovarian vein.

Objective Type 1 endometrial cancer (EC) is typically sex hormone sensitive; however, most women diagnosed with EC have already gone through menopause. Several studies have reported that the postmenopausal ovary is hormonally active, and estradiol (E2) production from the ovaries persists for as much as 10 years beyond menopause. The aim of this study was to evaluate whether sex steroid production from the ovaries contributes to the pathogenesis of type 1 EC. Materials and Methods This was a prospective study of 53 women treated for EC (28 cases of type 1 disease and 25 cases of type 2 disease). Serum specimens were collected from the peripheral and ovarian veins of participants undergoing bilateral oophorectomy. The sex steroid hormone levels and hormonal milieu on cervical cytology were evaluated as maturation value (MV). In addition, the degree of stromal hyperplasia of the ovary was evaluated histologically. Results Although the E2 levels of the peripheral veins did not show any significant differences [8.2 (5.1–12.4) vs 7.4 (5.1–11.7) pg/mL, respectively; P < 0.05], the patients with type 1 EC had a higher E2 level in the ovarian vein than those with type 2 EC [25 (13.8–42.5) vs 15 (10.0–23.0) pg/mL, respectively; P < 0.05]. There were also no significant differences in the rate of moderate to marked hyperplasia of the ovarian stroma between the groups; however, the thickness of the ovarian cortex demonstrated a correlation with the ovarian E2 level. In addition, the MV displayed a strong correlation with the ovarian E2 level, but not the peripheral E2 level. Conclusions The postmenopausal ovary is hormonally active, especially in patients with type 1 EC. The degree of ovarian stromal hyperplasia may (at least in part) contribute to the progression of type 1 EC, and MV may predict the level of E2 production from the ovaries in postmenopausal women.

Genitofemoral neuropathy after pelvic lymphadenectomy in patients with uterine corpus cancer.

Objective The aim of this study was to estimate the incidence, etiology, and outcomes of genitofemoral neuropathy after pelvic lymphadenectomy (PLD) for uterine corpus cancer. Materials and Methods The medical records of women who underwent PLD for uterine corpus cancer between June 2001 and June 2013 were reviewed. Information regarding neuropathy was directly reported by each subject. Results Thirty-two of 300 patients undergoing PLD during the defined period experienced postoperative neuropathy due to genitofemoral nerve injury, for an incidence of 10.7%. The patients treated with PLD with para-aortic lymphadenectomy (PALD) exhibited a lower rate of genitofemoral neuropathy than those treated without PALD (4.3% vs 13.5%, P = 0.01). The laparoscopy group displayed a higher rate of genitofemoral neuropathy than the laparotomy group (19.1% vs 9.1%, P = 0.04). A total of 81.3% of the patients experienced a full recovery, with a medium time to resolution of 6 months (3–12 months). The administration of adjuvant chemotherapy, including paclitaxel, did not extend the time to recovery. Conclusions Neuropathy resulting from genitofemoral nerve injury is not infrequent; however, most of the patients recover completely. In this study, the use of laparoscopic procedures increased the incidence of genitofemoral neuropathy, whereas that of PALD did not.

Foretinib (GSK1363089) induces p53-dependent apoptosis in endometrial cancer

Objective Foretinib (GSK1363089 or XL880), which is an oral multikinase inhibitor developed to primarily target the hepatocyte growth factor (HGF)/Met signaling pathway, has shown anti-tumor effects against some cancers in preclinical and clinical studies. Results HGF/Met signaling in endometrial cancer cell lines was stimulated in an autocrine manner, and was essential for cell survival. Inhibiting the HGF/Met signaling with foretinib induced p53-dependent apoptosis in endometrial cancer cell lines in vitro. Foretinib also showed significant anti-cancer effects in vivo in experiments using cell tumor xenografts. p53 mutations were observed in 37 (10.8%) of 344 endometrial cancer specimens. Conclusion The HGF/Met-MAPK/PI3K pathway in endometrial cancer is activated by HGF in an autocrine manner. Foretinib induces an anti-cancer effect through the anti-phosphorylation of Met, which results in the induction of p53-dependent apoptosis; foretinib was found to exert greater anti-cancer activity in endometrial cancer specimens with wild-type p53 than in specimens with p53 mutations. Our immunochemical analysis revealed that foretinib-induced p53-dependent apoptosis can be expected to have therapeutic potential in approximately 90% of endometrial cancer patients. Methods We evaluated the HGF/Met signaling pathway in endometrial cancer cell lines and assessed the anti-cancer effects of foretinib using in vitro and in vivo experimental models. Furthermore, endometrial cancer specimens were subjected to an immunohistochemical analysis.