Madoka Yamamoto

Demethylation restores SN38 sensitivity in cells with acquired resistance to SN38 derived from human cervical squamous cancer cells

Using seven monoclonal SN38-resistant subclones established from ME180 human cervical squamous cell carcinoma cells, we examined the demethylation effects of 5-aza-2′-deoxycytidine (5-aza-CdR) on the SN38-sensitivity of the cells as well as the expression of death-associated protein kinase (DAPK) in the SN38-resistant cells. The DAPK expression levels were evaluated among parent ME180 cells, SN38-resistant ME180 cells and cisplatin-resistant ME180 cells by methylation-specific DAPK-PCR, quantitative RT-PCR and western blot analysis. The SN38-resistant cells co-treated with SN38 and 5-aza-CdR strongly exhibited enhanced SN38-sensitivities resembling those found in the parent cells. In the SN38-resistant subclones, no relationships were found between the restored SN38 sensitivity and hypermethylation of the DAPK promoter, DAPK mRNA expression, DAPK protein expression and induction of DAPK protein after 5-aza-CdR treatment, unlike the strong suppression of 5-aza-CdR-induced DAPK protein expression in the cisplatin-resistant subclones. These findings indicate that reversibly methylated molecules, but not DAPK, may regulate SN38 resistance, and that demethylating agents can be strong sensitizing anticancer chemotherapeutic drugs for SN38-resistant cancers.

Downregulation of indoleamine 2, 3-dioxygenase expression in the villous stromal endothelial cells of placentas with preeclampsia

INTRODUCTION Previous studies have shown that indoleamine 2, 3-dioxygenase (IDO), an immunosuppressive enzyme that converts tryptophan to kynurenine, is expressed in the placenta and might play a role in the maintenance of pregnancy, although its associations with the pathogeneses of preeclampsia (PE) and fetal growth restriction (FGR) remain unclear. The objective of this study was to investigate the differences in IDO expression among normal, PE, and FGR placentas, and the associations between IDO expression and clinical symptoms, or the expression of fms-like tyrosine kinase receptor-1 (Flt-1). METHODS Immunohistochemical studies of IDO and Flt-1 expression were performed in human placentas that were complicated with FGR alone (n=19), PE alone (n=20), or both PE and FGR (n=39), and gestational age-matched controls (n=23). RESULTS It was found that IDO was expressed on endothelial cells in the villous stroma, while Flt-1 was located on trophoblast cells. The IDO expression level of the PE alone group was significantly lower than those of the FGR alone and control groups. The IDO expression of the PE+FGR group was significantly lower than that of the FGR alone group. Lower IDO expression was significantly correlated with more severe maternal hypertension or proteinuria in PE patients, who exhibited higher Flt-1 expression. The late onset PE patients exhibited significantly lower IDO expression than the early onset PE patients. CONCLUSION This study demonstrated that the downregulation of IDO expression on the endothelial cells of the villous stroma was associated with PE, but not FGR, suggesting that IDO might be involved in the pathophysiology of PE.

Adverse perinatal and neonatal outcomes in patients with chronic abruption–oligohydramnios sequence

Chronic abruption–oligohydramnios sequence (CAOS) is a clinical condition with lasting vaginal bleeding and oligohydramnios because of chronic placental abruption, which seems to cause preterm labor and neonatal chronic lung disease (CLD). This prompted us to explore the correlation between perinatal/neonatal outcomes and CAOS.

Ovarian steroid cell tumor, not otherwise specified, producing testosterone

Steroid cell tumor, not otherwise specified, is a rare type of ovarian sex cord‐stromal tumor with malignant potential. Some of these tumors produce testosterone. We describe a case of steroid cell tumor of the ovary associated with virilization. A 23‐year‐old nulliparous woman was found to have an ovarian tumor when she visited her primary doctor for virilization and oligomenorrhea. Magnetic resonance imaging revealed a solid left ovarian tumor 40 mm in size. Her laboratory data revealed elevated testosterone with normal levels of gonadotropins, estradiol, dehydroepiandrosterone sulfate and cortisol. She underwent left adnexectomy. On histopathologic and immunohistochemical analyses, the tumor was diagnosed as steroid cell tumor, not otherwise specified, without malignant behavior. After removal of the tumor, serum testosterone level decreased, and there have been no signs of recurrence.

Levels of serum-circulating angiogenic factors within 1 week prior to delivery are closely related to conditions of pregnant women with pre-eclampsia, gestational hypertension, and/or fetal growth restriction

We aimed to investigate maternal serum angiogenic marker profiles within 1 week prior to delivery in cases of gestational hypertension (GH), pre‐eclampsia (PE), and/or fetal growth restriction (FGR) with different clinical conditions.

Rapidly progressing large-cell neuroendocrine carcinoma arising from the uterine corpus: A case report and review of the literature

Large-cell neuroendocrine carcinoma (LCNEC) is a high-grade neuroendocrine tumor. LCNECs arising from the genital organs are highly malignant and rare, with <20 cases of LCNEC developing from the uterine endometrium reported to date. We herein present the case of a patient with LCNEC of the endometrium. The patient was a 52-year-old woman, who exhibited lower abdominal pain and rapid uterine enlargement during outpatient treatment for uterine myoma. The endometrial biopsy suggested a diagnosis of poorly differentiated carcinoma or carcinosarcoma. Based on magnetic resonance imaging and positron emission tomography/computed tomography, endometrial stromal sarcoma was suspected. The serum lactate dehydrogenase level was abnormally high. Due to the suspicion of stage IIIC malignant tumor of the uterine corpus, surgery was performed. The pathological diagnosis was stage IIIC2 LCNEC of the endometrium. Recurrence occurred in the vaginal stump, and concurrent chemoradiotherapy (CCRT) was initiated 1 month after the surgery. The residual lesions markedly shrank, but metastasis to the upper abdominal region and cervix subsequently developed. CCRT was attempted, but the associated adverse effects were severe and was switched to palliative treatment. The patient eventually succumbed to the disease 309 days after surgery.

Calreticulin Is Involved in Invasion of Human Extravillous Trophoblasts Through Functional Regulation of Integrin β1

Calreticulin (CRT), a molecular chaperone in the endoplasmic reticulum (ER), plays a variety of roles in cell growth, differentiation, apoptosis, immunity, and cancer biology. It has been reported that CRT is expressed in the human placenta, although its function in placental development is poorly understood. Appropriate invasion of extravillous trophoblasts (EVTs) into the maternal decidua is necessary for successful pregnancy. The objective of the present study was to investigate the expression and functional role of CRT in EVTs using the human EVT cell line HTR8/SVneo, in which CRT gene expression was knocked down. We found that CRT was highly expressed in the human placenta in the early stage of pregnancy and localized to the EVTs. CRT knockdown markedly suppressed the invasion ability of HTR8/SVneo cells. Furthermore, the adhesion to fibronectin was suppressed in the CRT-knockdown cells via the dysfunction of integrin α5β1. In the CRT-knockdown cells, terminal sialylation and fucosylation were decreased, and the core galactose-containing structure was increased in the N-glycans of integrin β1. In addition, the expression levels of several critical glycosyltransferases were changed in the CRT-knockdown cells, consistent with the changes in the N-glycans. These results showed that CRT regulates the function of integrin β1 by affecting the synthesis of N-glycans in HTR8/SVneo cells. Collectively, the results of the present study demonstrate that the ER chaperone CRT plays a regulatory role in the invasion of EVTs, suggesting the importance of CRT expression in placental development during early pregnancy.