Atsuko Hara

Cyclooxygenase-2 and inducible nitric oxide synthase expression in human astrocytic gliomas: correlation with angiogenesis and prognostic significance

Angiogenesis, which plays a key role in the development of astrocytic gliomas, depends on the local balance between various molecules that induce and inhibit neovascularization. Whereas recent experimental studies have indicated that cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) regulate angiogenesis by modulating vascular endothelial growth factor (VEGF) production, little is known about the relationships among expression of these markers, angiogenesis, and clinical outcome in astrocytic glioma cases. We therefore examined immunohistochemical expression of COX-2, iNOS, and VEGF in 51 high-grade astrocytomas including 31 glioblastomas (grade IV) and 20 anaplastic astrocytomas (grade III), 49 low-grade astrocytomas (grade II), and 43 reactive astrogliosis specimens, and determined the relationship with microvessel density (MVD) and prognostic significance. Stepwise increase of immunoreactive scores for COX-2, iNOS, and VEGF was found from astrogliosis, through low-grade to high-grade astrocytoma. The COX-2 expression strongly correlated with iNOS, VEGF, and high MVD, both overall and in all tumors, whereas iNOS expression was weakly associated with VEGF and high MVD. Univariate analysis revealed a significant association between COX-2 overexpression and a poor outcome. The findings for COX-2 and VEGF-related angiogenesis raise the possibility that the COX-2 pathway may contribute to astrocytic tumorigenesis by promoting new vessel formation with prognostic implications.

Loss of expression of the gene deleted in colon carcinoma (DCC) is closely related to histologic differentiation and lymph node metastasis in endometrial carcinoma

Although frequent loss of the tumor suppressor gene deleted in colon carcinoma (DCC) has been demonstrated in endometrial carcinoma, an alteration of the expression during normal menstrual cycle and tumorigenesis from hyperplastic lesions is still unclear.

Hypoxia-mediated cancer stem cells in pseudopalisades with activation of hypoxia-inducible factor-1α/Akt axis in glioblastoma☆☆☆

Pseudopalisades (Ps) around necrotic foci are severely hypoxic and overexpress hypoxia-inducible factor (HIF) in glioblastoma (GBM). Hypoxic regions have been proposed as one of several distinct niches for cancer stem cells (CSCs) in GBM, but little is known about the association between Ps features and CSC properties. Herein, we focused on the biological role of Ps lesions. In clinical cases of GBM, expression of hypoxia-related molecules including HIF-1α, Glut-1, p27(Kip1), and pAkt was significantly increased in perinecrotic Ps lesions compared with nonnecrotic areas and perinecrotic lesions lacking Ps features. Significantly higher expression levels of several CSC-related markers, including CD133, Sox2, CD44s, and aldehyde dehydrogenase (ALDH) 1, were also observed in Ps lesions, which were positively correlated with expression of hypoxia-related molecules and pAkt. Ps lesions also showed increased number of apoptotic cells and decreased bcl-2 and survivin expression compared with the surrounding tissue. Short-term exposure of astrocytoma cell lines to cobalt chloride, which is known to mimic the effect of hypoxia, caused an increase in expression of both hypoxia- and CSC-related markers, in line with increases in the ALDH(high) cell population and number of spheroids. Inhibition of endogenous Akt by LY294002 resulted in decreased expression of Sox2, ALDH1, and CD133, leading to enhancement of cobalt chloride-mediated apoptotic events due to altered ratio of bcl-2 to bax expression. These findings suggest that Ps lesions within GBM may serve as a specialized hypoxic niche, in which the HIF-1α/pAkt axis is activated, in response to severe hypoxia.

Up-regulation of pS2 expression during the development of adenocarcinomas but not squamous cell carcinomas of the uterine cervix, independently of expression of c-jun or oestrogen and progesterone receptors.

The pS2 gene product was firstly identified as an oestrogen‐induced molecule in a breast cancer cell line, while recent studies demonstrate a close association with mucus‐secreting epithelia. To assess pS2 expression in uterine cervical adenocarcinomas (C‐ACas) and invasive squamous cell carcinomas (C‐ISCCs), a series of 94 and 86 cases, respectively, as well as 77 samples of normal cervix, were immunohistochemically investigated and the results compared with data for expression of oestrogen and progesterone receptors (ER and PR) and c‐jun. RT‐PCR and western blot assays were also applied to 21 cervical carcinomas and 24 normal tissues. With cervical glandular lesions, significant up‐regulation of pS2 expression at both the mRNA and the protein levels was observed for adenocarcinomas in situ (AISs) and overt carcinomas, closely linked with mucinous differentiation and tumour grades. pS2 scores were inversely related to ERα status for all cervical glandular categories, while there was no association with ERβ and PR values. In squamous lesions, pS2 values did not differ between normal and malignant lesions, in contrast to the significant down‐regulation of ERα expression with tumour development. Although c‐jun expression significantly correlated with ERα values for all squamous categories, it did not relate to pS2 status in either C‐ACas or ISCCs. These results indicate that alterations in pS2 expression may occur relatively early in the development of cervical glandular, but not squamous lesions, independently of factors known to promote transcription of the pS2 gene. Copyright

Colonic Mucin-Carbohydrate Components in Colorectal Tumors and Their Possible Relationship to MUC2, p53 and DCC Immunoreactivities

To clarify changes in mucus components during colorectal tumorigenesis, we developed novel monoclonal antibodies (Abs) against carbohydrate chains of human colorectal mucin (HCM) obtained from normal sigmoid and rectal mucosae. A hundred and ninety-nine cases of colorectal carcinoma and 67 cases of tubular adenoma, along with 250 normal colonic tissue samples, were investigated immunohistochemically. The results were compared with clinical stage, survival and MUC2 (core protein of the intestinal type mucin) expression, as well as with the status of the p53 and DCC (deleted in colorectal carcinomas) genes. In the normal colonic epithelium, HCM14 Ab reacted with the cytoplasmic regions of the goblet cells and enterocytes, while HCM21 Ab bound to mucous droplets in the former, suggesting a more mature carbohydrate structure. Both HCM14 and 21 scores were significantly decreased in adenomas and carcinomas. This is in line with an altered PAS-Alcian blue staining, indicating accumulation of mucins with incomplete or abnormal glycosylation in tumors. Levels of HCM14 and 21 binding tended to show a positive correlation with expression of MUC2 and DCC, and a negative association with p53 protein accumulation in carcinomas, although there was no apparent link to Dukes stage or the prognostic outcome. These findings suggest a possible involvement of alterations in mucin carbohydrate in colorectal tumor development. The observed changes may be associated with loss of MUC2 and DCC expression, as well as with p53 protein accumulation.

Cryptogenic NORSE Its distinctive clinical features and response to immunotherapy

Objective: To report the distinctive clinical features of cryptogenic new-onset refractory status epilepticus (C-NORSE) and the C-NORSE score based on initial clinical assessments. Methods: A retrospective study was conducted for 136 patients with clinically suspected autoimmune encephalitis who underwent testing for autoantibodies to neuronal surface antigens between January 1, 2007, and August 31, 2016. Eleven patients with C-NORSE were identified. Their clinical features were compared with those of 32 patients with anti-NMDA receptor encephalitis (NMDARE). Results: The clinical outcome of 11 patients (median age, 27 years; 7 [64%] women) with C-NORSE was evaluated after a median follow-up of 11 months (range, 6–111 months). Status epilepticus was frequently preceded by fever (10/11 [91%]). Brain MRIs showed symmetric T2/fluid-attenuated inversion recovery hyperintensities (8/11 [73%]) and brain atrophy (9/11 [82%]). Only 2 of the 10 treated patients responded to the first-line immunotherapy, and 4 of the 5 patients treated with IV cyclophosphamide responded to the therapy. The long-term outcome was poor in 8 patients (73%). Compared with 32 patients with NMDARE (median age, 27 years; 24 [75%] women), those with C-NORSE had more frequent prodromal fever, status epilepticus, ventilatory support, and symmetric brain MRI abnormalities, had less frequent involuntary movements, absent psychobehavioral symptoms, CSF oligoclonal bands, or tumor association, and had a worse outcome. The C-NORSE score was higher in patients with C-NORSE than those with NMDARE. Conclusions: Patients with C-NORSE have a spectrum of clinical-immunological features different from those with NMDARE. The C-NORSE score may be useful for discrimination between them. Some patients could respond to immunotherapy.

Bifunctional roles of survivin-ΔEx3 and survivin-2B for susceptibility to apoptosis in endometrial carcinomas

AbstractPurpose Alternative splicing variants of survivin have different biological roles on cell kinetics. Here, we focused on the effects of different variants, including wild type (wt), survivin-ΔEx3, and survivin-2B, on apoptosis and cell proliferation in endometrial carcinomas (Em Cas).MethodsExpression of survivin-wt, survivin-ΔEx3, and survivin-2B with reference to cell death and proliferation was investigated, using Em Ca cell lines and its clinical tissues.ResultsIshikawa cells stably overexpressing either survivin-ΔEx3 (Surv-ΔEx3#34) or survivin-2B (Surv-2B#17) demonstrated considerably lower proliferative activity, along with up-regulation of p21waf1. After TNF-α treatment, Surv-ΔEx3#34 cells showed an increase in apoptotic cells, while the effects were relatively minor in Surv-2B#17 cells. In contrast, doxorubicin treatment resulted in increased apoptotic cells in Surv-2B#17 but not Surv-ΔEx3#34 cells, along with decreased expression of bcl-2 relative to bax. Control Ishikawa cells also showed relatively higher endogenous mRNA expression of survivin-ΔEx3 and survivin-2B during treatment of TNF-α and doxorubicin, respectively. In addition, exogenous overexpression of each survivin variant resulted in inhibition of other endogenous isoforms, indicating that the relative proportion may contribute to regulation of the splicing machinery. In clinical samples, level of survivin-ΔEx3 relative to either survivin-wt or survivin-2B was significantly higher in Em Cas than non-neoplastic lesions. Moreover, survivin-ΔEx3 and survivin-wt were positively correlated with apoptosis and cell proliferation, respectively, in Em Cas.ConclusionsThese findings provided evidence that the balance among expression level of survivin variants may contribute to modulation of cell kinetics in Em Ca cells.

RECTAL GRANULAR-CELL TUMOR DIFFICULT TO DISTINGUISH FROM CARCINOID TUMOR

A 60‐year‐old man had a positive fecal occult‐blood test on a medical check‐up. Colonoscopy revealed a yellowish‐white submucosal tumor 8 mm in diameter in the rectum. Endoscopic ultrasonography showed a well‐demarcated mass with a homogeneous, low‐level, internal echo in the second to third layers of the rectal wall. A carcinoid tumor was suspected, and the mass was resected endoscopically. Histopathological examination revealed a granular‐cell tumor. Gastrointestinal granular‐cell tumors rarely arise in the rectum, and the preoperative diagnosis of small lesions is often difficult. In our patient, granular‐cell tumor was difficult to differentially diagnose because the endoscopic and endoscopic ultrasonographic findings closely resembled those of carcinoid tumor. Interestingly, the endoscopic characteristics of the rectal granular‐cell tumor in our patient resembled those of a carcinoid tumor.

Investigation of IgG4-positive cell infiltration in biopsy specimens from cases of hypertrophic pachymeningitis.

This study was an immunohistological study of IgG4-positive cell infiltration in 6 cases of hypertrophic pachymeningitis excluding secondary hypertrophic pachymeningitis caused by infectious diseases such as aspergillosis. The cases included 5 males and 1 female, ranging in age from 36 to 82 years (mean, 55 years). A biopsy was performed in all of the cases for diagnostic purposes, revealing fibrous dural hyperplasia with nonspecific inflammatory cell infiltration histologically. Two of the 6 patients had been treated with steroids before the biopsy, which was taken for poor response to steroid treatment. In these two cases, some IgG-positive cell infiltration of the thickened dura was observed; however, most of the cells were IgG4-negative. In the remaining four cases, many IgG- and IgG4-positive cells infiltrated the thickened dura and the IgG4-positive/IgG-positive cell ratio exceeded 40%. One of these patients was finally diagnosed with IgG4-related sclerosing disease, since he was diagnosed subsequently with retroperitoneal fibrosis. There was no evidence of any other lesions associated with IgG4-related sclerosing disease, other than in the dura. It is not rare for IgG4-positive cells to appear in the dura in cases of hypertrophic pachymeningitis; however, no IgG4-related systemic disease is present in these cases. Hypertrophic pachymeningitis with IgG4-positive cells may have some kind of relation to other systemic autoimmune diseases.

Spontaneous brain tumor imaging of aged rat by crystal X-ray interferometer-based phase-contrast X-ray CT

Background Crystal X-ray interferometer-based phase-contrast X-ray computed tomography (C-PCCT) enables the depiction of internal structures of biological tissue without contrast agents. Purpose To determine the advantage of this technique in visualizing detailed morphological structures of a rare spontaneous brain tumor in an aged rat. Material and Methods An aged rat’s spontaneous brain tumor was imaged by C-PCCT without contrast agent. Three-dimensional (3D) images of the tumor microvasculature were reconstructed and compared with pathological pictures. Results C-PCCT depicted the tumor’s various pathological features clearly, e.g. its cell density and vasculature, and blood clots caused by hemorrhaging and/or hematomas. The obtained images resembled pathological pictures with a magnification of ×20 and were used to reconstruct 3D images of the tumor vascularity up to approximately 26 µm in diameter. Conclusion Since C-PCCT is able to depict various pathological conditions, it might be useful for cancer research.