Tomoyasu Bunai

EML4-ALK fusion transcripts, but no NPM-, TPM3-, CLTC-, ATIC-, or TFG-ALK fusion transcripts, in non-small cell lung carcinomas

EML4-ALK gene fusions have recently been discovered in a subset of human lung carcinomas, and fusions of the ALK tyrosine kinase gene with the NPM, TPM3, CLTC, ATIC, and TFG genes have been found in hematological malignancies. To elucidate the role of fusions between ALK and other genes in pulmonary carcinogenesis, we examined 77 non-small cell lung carcinomas (NSCLCs) for EML4-, NPM-, TPM3-, CLTC-, ATIC-, and TFG-ALK fusion transcripts by RT-PCR and subsequent sequencing analysis. Although no expression of NPM-, TPM3-, CLTC-, ATIC-, or TFG-ALK fusion transcripts were detected in any of the cases, expression of EML4-ALK fusion transcripts was detected in two (2.6%) of the 77 NSCLCs. In one of the two NSCLCs there was fusion between exon 13 of EML4 and exon 20 of ALK, i.e., variant 1, and in the other there was fusion between exon 20 of EML4 and exon 20 of ALK, i.e., variant 2. Both patients had a history of smoking, and histologically the carcinomas were adenocarcinoma. No somatic mutations were detected in the mutation cluster regions of the EGFR, K-RAS, and PIK3CA genes in these two carcinomas, however, a Pro177Ser mutation of the p53 gene was detected in the carcinoma that contained the variant 1 EML4-ALK fusion transcripts. In situ PCR of a paraffin block section showed that the carcinoma with expression of the variant 1 actually contained an EML4-ALK fusion gene. These results suggested that the EML4-ALK fusion gene product is involved in the carcinogenesis of a subset of NSCLCs.

PIK3CA mutation and amplification in human lung cancer

To explore the significance of phosphatidylinositol‐3‐kinase, catalytic, alpha (PIK3CA) in the carcinogenesis in human lung, mutations and copy number changes were investigated in 148 Japanese patients with primary cancer of the lung. For biological validation, the effects of exogenously expressed wild‐type and mutated PIK3CA were studied in an immortalized human airway epithelial cell line. Mutations in PIK3CA were found in five (3.6%) of the 139 available patients, and copy number gains were found in 21 (18.3%) of 115 patients, respectively. Overall, mutations or copy number gains were detected in 24 of the 106 patients (22.6%) for whom results in both analyses were available. The prevalence of copy number gains was higher in men, smokers, and in patients with squamous cell carcinoma than in the opposite categories. The copy number changes showed a trend toward higher prevalence in the earlier stages (P = 0.038). Interestingly, the presence of mutations and of copy number alterations were mutually exclusive in the present patients, implying that both entail equivalent oncogenic potential. Over‐expressed wild‐type PIK3CA and its two common mutants, K545E and H1047R, significantly enhanced the anchorage‐independent growth activity and migration activity of immortalized airway epithelium 16HBE14o– cells, but the effects of the K545E and H1047R mutants were more remarkable than those of the wild‐type. The present demonstrates an important role of PIK3CA in human lung carcinogenesis.

Depiction of microglial activation in aging and dementia: Positron emission tomography with [11C]DPA713 versus [11C](R)PK11195

The presence of activated microglia in the brains of healthy elderly people is a matter of debate. We aimed to clarify the degree of microglial activation in aging and dementia as revealed by different tracers by comparing the binding potential (BPND) in various brain regions using a first-generation translocator protein (TSPO) tracer [11C](R)PK11195 and a second-generation tracer [11C]DPA713. The BPND levels, estimated using simplified reference tissue models, were compared among healthy young and elderly individuals and patients with Alzheimer’s disease (AD) and were correlated with clinical scores. An analysis of variance showed category-dependent elevation in levels of [11C]DPA713 BPND in all brain regions and showed a significant increase in the AD group, whereas no significant changes among groups were found when [11C](R)PK11195 BPND was used. Cognito-mnemonic scores were significantly correlated with [11C]DPA713 BPND levels in many brain regions, whereas [11C](R)PK11195 BPND failed to correlate with the scores. As mentioned elsewhere, the present results confirmed that the second-generation TSPO tracer [11C]DPA713 has a greater sensitivity to TSPO in both aging and neuronal degeneration than [11C](R)PK11195. Positron emission tomography with [11C]DPA713 is suitable for the delineation of in vivo microglial activation occurring globally over the cerebral cortex irrespective of aging and degeneration.

Inverse relationship between the length of the EGFR CA repeat polymorphism in lung carcinoma and protein expression of EGFR in the carcinoma

There is a CA dinucleotide repeat polymorphism in the first intron of the epidermal growth factor receptor (EGFR) gene. Our aim was to examine the relationship between the CA repeat length in lung carcinoma and EGFR mutation, EGFR gene copy number, and EGFR protein expression level in the carcinoma.

A pilot study of serotonergic modulation after long‐term administration of oxytocin in autism spectrum disorder

Oxytocin (OT) and the serotonergic system putatively play important roles in autism spectrum disorder (ASD) etiology and symptoms, but no direct neurobiological evidence exists for long‐term OT administration effects on the brains serotonergic system. This pilot study examined 10 male participants with ASD who were administered OT intranasally for 8–10 weeks in an open‐label, single‐arm, nonrandomized, and uncontrolled manner. Positron emission tomography (PET) with a radiotracer (11C)−3‐amino‐4‐(2‐[(dimethylamino)methyl]phenylthio)benzonitrile (11C‐DASB) was used before and after OT treatment. The binding potential of serotonin transporter (11C‐DASB BPND) was then estimated. The main outcome measures were changes in 11C‐DASB BPND and their correlation with changes in symptoms. ASD participants showed significantly elevated 11C‐DASB BPND in the left inferior frontal gyrus extending to the left middle frontal gyrus. No significant correlation was found between the change in any clinical symptom and the change in 11C‐DASB BPND. This report of a pilot study is the first describing long‐term effects of OT on the brains serotonin system in ASD. Additional randomized controlled studies must be conducted to confirm whether activation of the serotonergic system contributes to the prosocial effect of OT in people with ASD. Autism Res 2017, 10: 821–828.

Subacute progressive ophthalmoplegia associated with dermatomyositis

Dermatomyositis is a systemic autoimmune disorder that primarily affects the skin and skeletal muscle in the extremities, and is characterized by weakness of the proximal groups of limb muscles. Extraocular muscle involvement is a very rare manifestation of dermatomyositis [5, 8]. We herein report a patient who manifested dermatomyositis with subacute progressive ophthalmoplegia. The patient was a 53-year-old Japanese male who presented with myalgia and difficulty in climbing stairs. He developed progressive diplopia with eyelid edema and ocular pain 2 weeks after presentation, followed by difficulties in raising his arms. No autoimmune, endocrinopathy, or malignant diseases were observed. The physical examination revealed the presence of Gottron’s papules on the dorsal surface of the hands, and a neurological examination showed symmetrical weakness of the proximal muscles, including the upper limbs muscles, and bilateral ophthalmoplegia with total limitations of eye movements (Fig. 1). There was no weakness of the facial muscles or bulbar palsy. Laboratory tests revealed an increased creatine kinase (CK) level (10,808 U/l; normal range, 25–190). There was no abnormal thyroid function or serum autoantibody, including antinuclear antibody, anti-acetylcholine receptor antibody, and anti-thyroid antibodies. No malignant tumors, including thymoma or thymic hyperplasia, were observed using whole-body CT and PET imaging. Intravenous edrophonium had no effect on the ophthalmoplegia. The repetitive nerve stimulation test was normal. The muscle biopsy at the left vastus medialis muscle revealed inflammatory myopathic changes, which showed the invasion of mononuclear cells into the interfascicular septae and within the fascicles, perifascicular atrophy, and variations in the muscle fiber size. An immunohistochemical analysis showed the mononuclear cells to be CD4and CD8-positive lymphocytes. Ragged red fiber or cytochrome c oxidase-negative fibers were absent. The patient was treated with 60 mg/day oral prednisolone. His ocular impairment, weakness of the proximal muscles, and elevated CK values became markedly improved 1 month after the steroid therapy. Orbital magnetic resonance imaging (MRI) scans revealed an increased thickness of the extraocular muscles on T1-weighted images (Fig. 2a) and high-intensity signals of the extraocular muscles on fat-suppressed T2-weighted images (Fig. 2c), which were both improved after the steroid therapy (Fig. 2b, d). No myositis-associated autoantibodies, including anti Jo-1, PM-Scl-100, PL-7, PL-12, EJ, OJ, KS, M2, Ku (p70/80), SRP, Rib-P antibodies and the antimitochondrial antibody of M2 subtype, were detectable in the serum. Previous reports have suggested that the ophthalmoplegia observed in inflammatory myopathies is caused by the S. Kono (&) T. Bunai T. Konishi K. Shirakawa H. Miyajima First Department of Medicine, Hamamatsu University School of Medicine, 1-20-1, Handayama, Hamamatsu 431-3192, Japan e-mail: satokono@hama-med.ac.jp

Neuroinflammation following disease modifying therapy in multiple sclerosis: A pilot positron emission tomography study

INTRODUCTION Chronic activation of microglia accelerates the neurodegenerative process in multiple sclerosis (MS). Although disease modifying therapy (DMT) is reportedly effective for neuroinflammatory responses in MS, the progression of neuroinflammation after DMT remains unclear. METHODS We evaluated microglial activation in six clinically stable relapsing-remitting MS patients after DMT by quantifying changes in translocator protein (TSPO) density using PET with [11C]DPA713, a selective TSPO tracer for microglial activation. All patients underwent [11C]DPA713 PET scans twice, and the scans were conducted one year apart. The binding potential (BPND) of the tracer was estimated using a simplified reference tissue model. RESULTS [11C]DPA713 BPND measured at 6months after DMT was significantly higher in the MS group than that in the control group. Compared with the first PET measurement, the one-year PET measurement revealed significantly elevated [11C]DPA713 BPND in broader brain regions covering the temporal and parietal cortices after one year of DMT. CONCLUSIONS The current results indicate that microglial activation may proceed in the entire brain of clinically stable MS patients even after receiving DMT.

Alterations in Phase-Related Prefrontal Activation During Cognitive Tasks and Nicotinic α4β2 Receptor Availability in Alzheimer’s Disease

BACKGROUND Evidence shows that the cholinergic system plays an important role in regulating working memory and that working memory-related prefrontal activation decreases with age and neuronal degeneration, such as Alzheimers disease (AD). However, the relation between attention-related α4β2 nicotinic cholinergic function and task-induced prefrontal activation especially time course-related activation remains to be explored. OBJECTIVE We aimed to elucidate the relationship between changes in task-induced oxy-hemoglobin concentration (cerebral blood flow, CBF) in the prefrontal cortex and the availability of α4β2 nicotinic receptors in the brain of AD patients in light of their task performance. METHODS Eleven mild-to-moderate AD patients and eleven normal elderly subjects underwent the near-infrared spectroscopy during easy and difficult working memory tasks for estimating prefrontal CBF changes and positron emission tomography with the α4β2 tracer [18F]2FA-85380 ([18F]2FA) for measuring the α4β2 nicotinic receptor binding. RESULTS Significant correlations between mean oxy-hemoglobin concentration in the channels with significant [group] main effects and prefrontal [18F]2FA binding were observed during the early easy task period in the normal group and during the late difficult task in the AD group. In addition, those prefrontal CBF responses were significantly correlated with not correct performance but the execution time to spend. CONCLUSION The α4β2 nicotinic acetylcholine receptors in the prefrontal cortex play an important role in increasing prefrontal activation when attending to novel stimuli, irrespective of the accuracy of the outcome. A delay in the cholinergic-induced increase in prefrontal activation in AD patients might explain their delayed responses in the cognitive task.

The Possible Link between GABAergic Dysfunction and Cognitive Decline in a Patient with Idiopathic Hypoparathyroidism.

Idiopathic hypoparathyroidism (IHP) is accompanied by cognitive impairment. We report the case of a 70-year-old IHP patient with cognitive disturbance. Brain computed tomography showed bilateral calcification in basal ganglia, thalamus, and cerebellum. Neuropsychological assessment revealed low scores for intelligence, memory, and perseverative errors. Brain positron emission tomography showed a significant reduction in [(18)F]-Fludeoxyglucose (FDG) uptake in bilateral frontal, left temporal and parietal cortices, along with a marked reduction in [(11)C]-flumazenil binding in left frontal, temporal, parietal, and bilateral cerebellum. These findings suggest cognitive impairment in IHP may be ascribed to GABAergic dysfunction, thus leading to, or coexisting with, cerebral hypometabolism.