Kentaro Ohara

Histopathological investigation of glioblastomas resected under bevacizumab treatment

To date, no clinical observations have been reported for histopathological changes in human gliomas under antiangiogenic treatment. We collected six glioblastomas resected under bevacizumab treatment. Histopathological investigation was performed by hematoxilyn-eosin staining and immunohistochemistry for CD34, VEGF, VEGFR1/2, HIF-1α, CA9, and nestin as compared to eleven control glioblastomas to assess the differences in histological features, microvessel density, expression of VEGF and its receptors, tumor oxygenation, and status of glioma stem-like cells. In the six tumors resected under bevacizumab, microvascular proliferation was absent, and microvessel density had significantly decreased compared with that of the controls. The expressions of VEGF and its receptors were downregulated in two cases of partial response. HIF-1α or CA9 expression was decreased in five of the six tumors, whereas the decreased expression of these markers was noted in only one of the 11 control glioblastomas. The expression of nestin significantly decreased in the six tumors compared with that of the controls, with the remaining nestin-positive cells being relatively concentrated around vessels. We provide the first clinicopathological evidence that antiangiogenic therapy induces the apparent normalization of vascular structure, decrease of microvessel density, and improvement of tumor oxygenation in glioblastomas. These in situ observations will help to optimize therapy.

Src Plays a Key Role in ADAM28 Expression in v-src–Transformed Epithelial Cells and Human Carcinoma Cells

ADAM28, a disintegrin and metalloproteinase 28, is overexpressed by carcinoma cells with direct correlations with carcinoma cell proliferation and progression in human lung and breast carcinomas. However, the molecular mechanisms of ADAM28 gene expression in carcinoma cells remain elusive. Herein, we investigated the expression of ADAM28 in Madin-Darby canine kidney epithelial cells transformed by oncogenes, including v-src, LMP1, ErbB2, Ha-Ras, and c-Fos, and found that v-src transformants selectively induce ADAM28. Implantation of the v-src transformants showed a progressively growing tumor, which was significantly suppressed by local injections of anti-ADAM28 antibody. ADAM28 expression in v-src transformants was partially inhibited by treatment with inhibitors to Src kinase, mitogen-activated protein kinase kinase (MEK), phosphatidylinositol 3-kinase (PI3K), or mammalian target of rapamycin, and abrogated by v-Src kinase inhibitor, radicicol, or a mixture of MEK and PI3K inhibitors. Human carcinoma cell lines of the lung, breast, ovary, kidney, and colon showed ADAM28 expression, which was correlated with phosphorylation of c-Src and suppressed by the inhibitors in a similar way to v-src transformants. IHC of the human tumor tissues demonstrated co-expression of ADAM28 and phosphorylated Src in neoplastic cells of the breast, lung, and colon carcinomas and some adenomas of the colon, but not in nonneoplastic colon mucosa. Our data provide, to the best of our knowledge, the first evidence that Src is an inducer of ADAM28 gene expression through the MEK/extracellular signal-regulated kinase and PI3K/mammalian target of rapamycin pathways.

Childhood Sjögren syndrome presenting as acute brainstem encephalitis

Sjögren syndrome is an autoimmune disease characterized by dry mouth and eyes, known as sicca symptoms. The exact spectrum of neurological involvement, especially of the central nervous system, in childhood Sjögren syndrome has not been well defined. We report a girl who presented with acute febrile brainstem encephalitis. In retrospect, she had exhibited a preceding history of recurrent conjunctivitis and strong halitosis that could be considered as sicca symptoms. The histopathology results of a minor salivary biopsy, the presence of anti-SSA/Ro antibody, and keratoconjunctivitis confirmed the diagnosis of Sjögren syndrome. Commonly observed features in previously reported patients with childhood Sjögren syndrome and central nervous system complications have included fever at the time of neurologic presentation, cerebrospinal fluid pleocytosis, abnormal neuroimaging, and positivity for several specific antibodies. In children presenting with unknown acute febrile encephalopathy, Sjögren syndrome should be included in the differential diagnosis, especially when sicca symptoms are present.

A large coronary aneurysm and its probable precursor lesions in a patient with autosomal dominant polycystic kidney disease: An implication for the process of aneurysmogenesis

Coronary artery aneurysms are rare complications of autosomal dominant polycystic kidney disease (ADPKD), and their pathogenesis remains poorly understood. We report an autopsy case of a 64‐year‐old ADPKD patient with an asymptomatic, large (4 cm in diameter) saccular aneurysm arising from the left circumflex (LCX) branch of the coronary artery with only mild atherosclerotic changes. Autopsy also revealed small, focal defects of media with or without microaneurysm formation in the LCX, mesenteric and renal arteries, and a fibromuscular dysplasia‐like lesion with microaneurysm in the common iliac artery. Since polycystin‐1 and ‐2 are expressed in arterial smooth‐muscle cells, these findings imply that abnormal polycystin expression in ADPKD initially causes the focal medial defects, some of which might later progress to microaneurysms and then overt aneurysms. To the best of our knowledge, this is the first description of the pathologic findings of an ADPKD‐associated coronary aneurysm and its probable precursor lesions in arteries.

Clinical and Molecular Prognostic Factors for Long-Term Survival of Patients with Glioblastomas in Single-Institutional Consecutive Cohort

OBJECTIVE The purpose of this study was to clarify the clinical and molecular characteristics associated with long-term survival in patients with glioblastoma. METHODS We analyzed the characteristics of 96 glioblastoma patients. Long-term survivors (LTSs) were classified into moderate LTSs (mLTSs), who survived >3 years, and LTSs, who survived >5 years, and compared with short-term survivors (STSs). Clinical and molecular factors were investigated. RESULTS Younger age, better recursive partitioning analysis class, lack of subventricular zone (SVZ) involvement, promoter methylation of the O6-methylguanine-DNA methyltransferase (MGMT) gene, and loss of 19q were associated with mLTSs as compared with STSs. After adjustment for these factors, younger age and MGMT methylation remained independently associated with mLTSs. Younger age, better recursive partitioning analysis class, lack of SVZ involvement, and loss of 19q were associated with LTSs as compared with STSs. After adjustment, younger age and better preoperative Karnofsky performance scale (KPS) score remained independently associated with LTSs. Kaplan-Meier analyses revealed that younger age (<50 years), better preoperative KPS score (≥70), lack of SVZ involvement, and loss of 19q were associated with longer overall survival. In the multivariate analysis, only age was significantly associated with overall survival. CONCLUSIONS Younger age and better preoperative KPS score were the characteristics associated with LTSs as compared with STSs. MGMT promoter methylation was associated with mLTSs, but not with LTSs. In addition, lack of SVZ involvement and loss of 19q might be prognostic for longer survival.

ADAM28 is expressed by epithelial cells in human normal tissues and protects from C1q‐induced cell death

ADAM28 (disintegrin and metalloproteinase 28), which was originally reported to be lymphocyte‐specific, is over‐expressed by carcinoma cells and plays a key role in cell proliferation and progression in human lung and breast carcinomas. We studied ADAM28 expression in human normal tissues and examined its biological function. By using antibodies specific to ADAM28, ADAM28 was immunolocalized mainly to epithelial cells in several tissues, including epididymis, bronchus and stomach, whereas lymphocytes in lymph nodes and spleen were negligibly immunostained. RT‐PCR, immunoblotting and ELISA analyses confirmed the expression in these tissues, and low or negligible expression by lymphocytes was found in the lymph node and spleen. C1q was identified as a candidate ADAM28‐binding protein from a human lung cDNA library by yeast two‐hybrid system, and specific binding was demonstrated by binding assays, immunoprecipitation and surface plasmon resonance. C1q treatment of normal bronchial epithelial BEAS‐2B and NHBE cells, both of which showed low‐level expression of ADAM28, caused apoptosis through activation of p38 and caspase‐3, and cell death with autophagy through accumulation of LC3‐II and autophagosomes, respectively. C1q‐induced cell death was attenuated by treatment of the cells with antibodies against the C1q receptor gC1qR/p33 or cC1qR/calreticulin. Treatment of C1q with recombinant ADAM28 prior to addition to culture media reduced C1q‐induced cell death, and knockdown of ADAM28 using siRNAs increased cell death. These data demonstrate that ADAM28 is expressed by epithelial cells of several normal organs, and suggest that ADAM28 plays a role in cell survival by suppression of C1q‐induced cytotoxicity in bronchial epithelial cells.

Histopathological vascular investigation of the peritumoral brain zone of glioblastomas

To date, no histopathological vascular investigation focusing on peritumoral brain zone (PBZ) has been reported for glioblastoma. We analyzed 10 newly diagnosed cases of glioblastomas. For these PBZs, histopathological investigation was performed by hematoxylin–eosin (H&E) staining and immunohistochemistry was analyzed for CD31, CD34, Factor VIII, VEGF, VEGFR-1/2, Ki67, p53 and nestin. Although it was difficult to identify PBZ by H&E, Ki67 and p53 staining, there were apparent differences in nestin staining among PBZ, tumor core (TC), and normal zone (NZ). Therefore, in this study, we divided PBZ from TC and NZ by nestin staining. Differences in histological features, microvessel density, expression of VEGF and its receptors were assessed for PBZ, TC and NZ. The microvessel density, as determined by counting CD31, CD34 and VEGF receptors, and VEGF-A expression were lower in PBZ than TC. The expression patterns for CD31, CD34 and VEGF receptors in vessels show dissociation in PBZ. In addition, the vascular characteristics of the PBZ may correlate with findings of radiographic imaging. We provide the first clinicopathological evidence that PBZ exhibits unique angiogenic characteristics. These in situ observations will help to elucidate the mechanisms of tumor recurrence.

Comprehensive genetic characterization of rosette-forming glioneuronal tumors: Independent component analysis by tissue microdissection

A rosette‐forming glioneuronal tumor (RGNT) is a rare mixed neuronal‐glial tumor characterized by biphasic architecture of glial and neurocytic components. The number of reports of genetic analyses of RGNTs is few. Additionally, the genetic background of the unique biphasic pathological characteristics of such mixed neuronal‐glial tumors remains unclear. To clarify the genetic background of RGNTs, we performed separate comprehensive genetic analyses of glial and neurocytic components of five RGNTs, by tissue microdissection. Two missense mutations in FGFR1 in both components of two cases, and one mutation in PIK3CA in both components of one case, were detected. In the latter case with PIK3CA mutation, the additional FGFR1 mutation was detected only in the glial component. Moreover, the loss of chromosome 13q in only the neurocytic component was observed in one other case. Their results suggested that RGNTs, which are tumors harboring two divergent differentiations that arose from a single clone, have a diverse genetic background. Although previous studies have suggested that RGNTs and pilocytic astrocytomas (PAs) represent the same tumor entity, their results confirm that the genetic background of RGNTs is not identical to that of PA.

A case of papillary tumor of the pineal region with a long clinical history: molecular characterization and therapeutic consideration with review of the literature

A 37-year-old male patient initially visited another hospital at the age of 22 complaining of headache. At that hospital, magnetic resonance imaging (MRI) of his brain showed a heterogeneously enhancing mass with hydrocephalus in the pineal gland. The patient underwent ventriculo-peritoneal shunt placement with partial tumor resection of the mass, although pathologically, no definitive diagnosis was made regarding the tumor. At that time, he had left lower quadrantanopia and disturbances of extraocular movements (upward gaze palsy and limitation of lateral gaze). He was then followed as an outpatient at that hospital. When the patient was 31 years old, the headache returned and MRI scans of his brain revealed recurrence of the pineal tumor. He underwent two further operations via the occipital transtentorial approach. The pathological diagnosis was atypical choroid plexus papilloma. The patient then visited our hospital for a second opinion and further treatment (Fig. 1a). He first underwent a biopsy, and the diagnosis was pineal parenchymal tumor with intermediate differentiation (PPITD). He was administered two courses of chemotherapy with carboplatin and etoposide followed by focal irradiation (40 Gy in 20 fractions). However, the tumor was not very responsive to these treatments, and the patient underwent another operation for the residual tumor (partial removal) the following year; once again, the pathological diagnosis was PPTID. After the operation, he underwent intensity-modulated radiation therapy (IMRT) (30 Gy in 15 fractions). The residual tumor responded well to IMRT (partial response) (Fig. 1b, c), and the patient was followed as an outpatient. Five years after IMRT, MRI and positron emission tomography scans showed enlargement of the residual tumor (Fig. 1d, e). In addition, the patient’s symptoms were deteriorating, with progressive impairment of cognitive function and eye movement and an increase in gait disturbances. Therefore, he underwent another operation via high parietal approach. The tumor was only partially removed because of strong adhesion to the internal cerebral vein penetrating the tumor (Fig. 1f). This time, the pathological diagnosis was papillary tumor of the pineal region (PTPR). By this time, the patient could not walk due to weakness of extremities. He also suffered from cognitive deterioration and the majority of his time was spent in bed [Karnofsky performance status (KPS) 30]. Based on the reported similarities between PTPR and ependymoma, the presence of extensive perifocal edema and a few reports of success in the literature, the patient was treated with the combination chemotherapy of oral temozolomide (150 mg/m, days 1–5, 28-day cycle) and intravenous bevacizumab (7.5 mg/kg, day 0, every 4 weeks). The tumor showed a partial response to the combination therapy (Fig. 1g) and the patient’s symptoms began to gradually improve. To date, he has undergone a total of 16 courses of oral temozolomide and 18 courses of bevacizumab without any adverse events, and the treatment is still ongoing. The maximum response of the tumor was obtained after 6 courses of the combination chemotherapy, and the tumor volume has remained decreased for more than 14 months. Figure 1h shows the tumor 1 year after the initiation of the combination chemotherapy. The patient is & Hikaru Sasaki hsasaki@a5.keio.jp

Nontuberculous mycobacteria-associated spindle cell pseudotumor of the nasal cavity: a case report.

Mycobacterial spindle cell pseudotumor (MSP) is a rare mass‐forming lesion caused by mycobacterial infection, mostly in immunocompromised patients. Since it is composed of a proliferation of spindle‐shaped fibrohistiocytic cells without forming epithelioid cell granulomas, histological distinction from other spindle cell lesions is often difficult and its pathophysiology is poorly understood. MSP arising in the nasal cavity is extremely rare, and only two cases have been reported previously. Here we report a case of MSP of the nasal cavity in an 83‐year‐old man with no evidence of immunodeficient state. The resected tumor consisted of spindle cells, which contained numerous acid‐fast bacilli in the cytoplasm. By polymerase chain reaction and sequencing using DNA extracted from the paraffin sections, the bacilli were identified as Mycobacterium intracellulare. Immunohistochemistry revealed that the spindle cells were positive for CD68, CD11c and S100 protein, confirming the histiocytic nature of these cells. They were also positive for CD163 and CD204, suggesting that they showed a phenotype similar to alternatively activated (M2) macrophages and the phenotype might contribute to the maintenance of mycobacterial infection despite apparent immunocompetence of the host.