Yu Abe

A genome-wide association study identifies RNF213 as the first Moyamoya disease gene.

Moyamoya disease (MMD) shows progressive cerebral angiopathy characterized by bilateral internal carotid artery stenosis and abnormal collateral vessels. Although ∼15% of MMD cases are familial, the MMD gene(s) remain unknown. A genome-wide association study of 785 720 single-nucleotide polymorphisms (SNPs) was performed, comparing 72 Japanese MMD patients with 45 Japanese controls and resulting in a strong association of chromosome 17q25-ter with MMD risk. This result was further confirmed by a locus-specific association study using 335 SNPs in the 17q25-ter region. A single haplotype consisting of seven SNPs at the RNF213 locus was tightly associated with MMD (P=5.3 × 10−10). RNF213 encodes a really interesting new gene finger protein with an AAA ATPase domain and is abundantly expressed in spleen and leukocytes. An RNA in situ hybridization analysis of mouse tissues indicated that mature lymphocytes express higher levels of Rnf213 mRNA than their immature counterparts. Mutational analysis of RNF213 revealed a founder mutation, p.R4859K, in 95% of MMD families, 73% of non-familial MMD cases and 1.4% of controls; this mutation greatly increases the risk of MMD (P=1.2 × 10−43, odds ratio=190.8, 95% confidence interval=71.7–507.9). Three additional missense mutations were identified in the p.R4859K-negative patients. These results indicate that RNF213 is the first identified susceptibility gene for MMD.

Clinical and immunological evaluation of zoledronate-activated Vγ9γδ T-cell-based immunotherapy for patients with multiple myeloma

OBJECTIVE To evaluate the potential anti-tumor activity of zoledronate-activated Vgamma9gammadelta T cells in vivo, we initiated a pilot study involving administration of zoledronate-activated Vgamma9gammadelta T lymphocyte-activated killer (LAK) cells to patients with multiple myeloma. MATERIALS AND METHODS Subjects (n = 6) received four intravenous infusions at 2-week intervals of zoledronate-activated Vgamma9gammadelta T LAK cells generated from the culture of peripheral blood mononuclear cells (PBMCs) in the presence of zoledronate and interleukin-2. If the M-protein level in the patients serum remained at baseline following four intravenous infusions, the patient underwent four more treatments at 4-week intervals. Subjects (n = 6) received a median of 0.99 x 10(9) Vgamma9gammadelta T LAK cells per infusion. RESULTS No serious treatment-related adverse effects were observed during the study period. The percentage of Vgamma9gammadelta T cells in PBMCs and absolute numbers of Vgamma9gammadelta T cells in peripheral blood, particularly those of CD45RA(-)CD27(-) effector memory (TEM) Vgamma9gammadelta T-cell subsets increased in all the patients. Percentages of Vgamma9gammadelta T cells and TEM Vgamma9gammadelta T cells in bone marrow also increased in all the patients so far tested. M-protein levels in the serum remained at baseline in four of six patients and increased in two of six patients. Soluble major histocompatibility complex class I chain-related antigen A was detected only in the serum of patients whose M-protein level increased. CONCLUSION Administration of zoledronate-activated Vgamma9gammadelta T LAK cells is a safe and promising immunotherapy approach for treatment of patients with multiple myeloma.

Prevalence and clinical features of Costello syndrome and cardio-facio-cutaneous syndrome in Japan: findings from a nationwide epidemiological survey.

Costello syndrome and cardio‐facio‐cutaneous (CFC) syndrome are congenital anomaly syndromes characterized by a distinctive facial appearance, heart defects, and intellectual disability. Germline mutations in HRAS cause Costello syndrome, and mutations in KRAS, BRAF, and MAP2K1/2 (MEK1/2) cause CFC syndrome. Since the discovery of the causative genes, approximately 150 new patients with each syndrome have been reported. However, the clinico‐epidemiological features of these disorders remain to be identified. In order to assess the prevalence, natural history, prognosis, and tumor incidence associated with these diseases, we conducted a nationwide prevalence study of patients with Costello and CFC syndromes in Japan. Based on the result of our survey, we estimated a total number of patients with either Costello syndrome or CFC syndrome in Japan of 99 (95% confidence interval, 77–120) and 157 (95% confidence interval, 86–229), respectively. The prevalences of Costello and CFC syndromes are estimated to be 1 in 1,290,000 and 1 in 810,000 individuals, respectively. An evaluation of 15 adult patients 18–32 years of age revealed that 12 had moderate to severe intellectual disability and most live at home without constant medical care. These results suggested that the number of adult patients is likely underestimated and our results represent a minimum prevalence. This is the first epidemiological study of Costello syndrome and CFC syndrome. Identifying patients older than 32 years of age and following up on the patients reported here is important to estimate the precise prevalence and the natural history of these disorders.

Epilepsy in RAS/MAPK syndrome: Two cases of cardio-facio-cutaneous syndrome with epileptic encephalopathy and a literature review

We report two individual cases of cardio-facio-cutaneous (CFC) syndrome with severe neurological impairment consisting of infantile spasms with hypsarrhythmia and refractory epilepsy with multifocal epileptic paroxysms such as modified hypsarrhythmia. Both cases shared diffuse brain atrophy and severely delayed myelination on neuroimaging. Genetic analysis revealed individual heterozygous mutations in the KRAS (phenotype of CFC/Noonan syndrome) and BRAF genes (phenotype of CFC syndrome). Neurological impairment in cases with mutations in the RAS/MAPK (mitogen activated protein kinase) signal pathway may be more severe, and could be linked to some forms of refractory epilepsy, especially epileptic encephalopathy that includes infantile spasms.

The usefulness of subtraction ictal SPECT and ictal near-infrared spectroscopic topography in patients with West syndrome.

The recent findings on subtraction ictal SPECT and ictal near-infrared spectroscopic topography in patients with West syndrome were summarized and its availability for presurgical evaluation was discussed. The subtraction ictal SPECT study in patients with West syndrome demonstrated the cortical epileptic region and subcortical involvement, which may consist of epilepsy networks related to the spasms. Moreover, subtraction ictal SPECT may have predictive power for short-term seizure outcome. Patients with a symmetric hyperperfusion pattern are predicted to have a better seizure outcome, whereas patients with asymmetric hyperperfusion pattern may develop poor seizure control. Importantly, asymmetric MRI findings had no predictive power for seizure outcome. Multichannel near-infrared spectroscopic topography applied to the patients with West syndrome detected an increase in regional cerebral blood volume in multiple areas which were activated either simultaneously or sequentially during spasms. Topographic changes in cerebral blood volume were closely correlated with spasm phenotype, suggesting that the cortex is involved in the generation of spasms. In conclusion, subtraction ictal SPECT may be considered as a useful tool for presurgical evaluation of patients with West syndrome and investigation of the pathophysiology of spasms. The ictal near-infrared spectroscopic topography should be more investigated to see if this is useful tool for presurgical evaluation.

Xq26.1-26.2 gain identified on array comparative genomic hybridization in bilateral periventricular nodular heterotopia with overlying polymicrogyria

Periventricular nodular heterotopia (PNH) with overlying polymicrogyria (PMG) is a recently described, developmental brain malformation; however, the causative genes of this malformation have not yet been identified. We report on a 5‐year‐old Japanese male with bilateral PNH with overlying PMG. He had mild intellectual disability, distinctive facial features, short stature, and microcephaly, with cardiac disorders. No mutation was identified in Sanger sequences for FLNA and ARFGEF2; however, array comparative genomic hybridization revealed an approximately 0.8Mb gain at Xq26.1‐26.2, which included three genes: IGSF1, OR13H1, and FIRRE. We identified the same 3‐copy gain in his mother; despite identifying the same abnormality in the mother, it must still be considered as a possible cause for the abnormalities, as X‐inactivation in the mother could have led to her not expressing the same phenotype. This case may provide important clues for identifying the genes responsible and help in the understanding of the pathogenesis of this disorder.

Unique discrepancy between cerebral blood flow and glucose metabolism in hemimegalencephaly

Hemimegalencephaly (HME) presents as severe refractory seizures and requires early surgical treatment to prevent progression to catastrophic epilepsy. Single-photon emission computed tomography (SPECT) and positron emission tomography (PET) are useful imaging techniques for the presurgical evaluation of patients with intractable epilepsy. However, the results in HME are variable and no study has compared SPECT and PET performed at around the same time. We performed SPECT and PET for nine patients with HME, which was defined as a whole or part of affected hemisphere enlargement (three males, six females; age range 0.5-20 years). The ictal and interictal states were determined based on the presence or absence of clinical seizures during all PET examinations and majority of SPECT examinations. The perfusion pattern in the malformed hemisphere was increased or equal, despite the reduced glucose metabolism in six out of nine patients. Five of the six patients who underwent early surgical treatment showed this kind of perfusion/metabolism discrepancy. Importantly, even the non-affected hemisphere in early infantile cases already lacked the normal hypoperfusion and hypometabolism patterns of immature frontal lobes, which was most prominent in case with poor surgical prognosis. In all six surgical patients, epileptic seizures appeared before 4 months of age. By contrast, none of the non-surgical patients had seizures before 4 months of age. In conclusion, although the number of patients examined is small and the result is still preliminary, the perfusion/metabolism discrepancy found in this study may show potential characteristic aspect of HME and further study with simultaneous EEG recording will make clear if this finding can be useful indicator for early surgical treatment in HME.

Smith-Magenis Syndrome With West Syndrome in a 5-Year-Old Girl: A Long-Term Follow-Up Study

Smith-Magenis syndrome is characterized by multiple congenital anomalies and mental retardation caused by the heterozygous deletion of chromosomal region 17p11.2. We present a long-term follow-up study of a girl with Smith-Magenis syndrome and West syndrome. West syndrome became apparent at 7 months of age. Since then, mental retardation, particularly in terms of language development, became increasingly more obvious. The patients spasms and hypsarrhythmia disappeared after a course of adrenocorticotropic hormone therapy, but focal seizures reappeared at the age of 3 years and 3 months. Her craniofacial dysmorphia and mental retardation became increasingly evident compared to her condition at the onset of West syndrome. Chromosome analysis detected the characteristic 17p deletion, which was then confirmed via fluorescent in situ hybridization analysis. This is the second report of a patient with Smith-Magenis syndrome and West syndrome; taken together, these results suggest that Smith-Magenis syndrome may be a further cause of West syndrome.

The clinical significance of decrease in CD138 positive cell ratio in multiple myeloma

CD138 has been considered to be strongly expressed in multiple myeloma cells. However, CD138⁺ cells were decreased in some patients during the course of treatment. To clarify the clinical significance of this finding, we evaluated the correlations of CD138 levels with laboratory data employing flow cytometry. We found that CD138⁺ cells were decreased in 12 patients during treatment and were retained in the remaining 105 patients throughout their clinical courses. For nine (75%) patients in the CD138⁺ cells reduced group, median survival time was 25 months after the reduction in CD138⁺ cells was detected, and all nine died of myeloma. Furthermore, extramedullary lesions and specific cytogenetic abnormalities [del(17p), t(4;14), amplification of c-MYC] were observed in some patients when the number of CD138⁺ cells started to decrease. Interestingly, 2 of 3 patients who survived until the end of observation period showed re-increase in their CD138⁺ levels. Taking these observations together, it is unclear whether reduction of the number of CD138⁺ cells is associated with a poor prognosis and resistance to drugs. However, if treatment does not produce a reincrease in CD138⁺ levels, long term survival might be difficult to achieve.

Amelioration of NK cell function driven by Vα24 + invariant NKT cell activation in multiple myeloma

NK cells represent a first line of immune defense, but are progressively dysregulated in multiple myeloma (MM) patients. To restore and facilitate their antitumor effect, NK cells are required in sufficient quantities and must be stimulated. We initially assessed the proportions of NKT and NK cells in 34 MM patients. The frequencies of both in PBMC populations correlated with those in BMMNCs irrespective of low BMMNC numbers. We then assessed the adjunctive effect of stimulating NKT cells with CD1d and α-GalCer complexes on the NK cells. The expression of NKG2D on CD56dimCD16+ NK cells and DNAM-1 on CD56brightCD16- NK cells increased after NKT cell activation. Apparently, NK cell-mediated anti-tumor effects were dependent on NKG2D and DNAM-1 ligands on myeloma cells. Thus, NK cell function in patients could be ameliorated, beyond the effect of immunosuppression, by NKT cell activation. This NKT-driven NK cell therapy could represent a potential new treatment modality.