Insulin-like growth factor II mRNA-binding protein 3 (IMP3) has been reported to enhance proliferation and invasion in various cancers. The role of IMP3 on neuroblastoma (NB) is unknown. We aimed to clarify the prognostic significance of IMP3 expression in patients with NB. By microarray analysis, high IMP3 expression was found in patients with poor outcome. IMP3 expression in 90 NB samples was analyzed by immunohistochemical staining to correlate with clinical stages, histology, and patient outcome. Positive IMP3 expression was detected in 52 of 90 patients, and was significantly correlated with undifferentiated histology, advanced stages, MYCN amplification, and poor outcome. In subgroups, positive IMP3 expression could predict an even worse prognosis in patients with advanced disease, with normal MYCN status, or with MYCN amplification (P = 0.005, P = 0.001, and P = 0.033, respectively). The IMP3 expression decreased by induction of differentiation with retinoid acid treatment in SK-N-DZ and SK-N-SH cells in vitro. The invasion ability of NB cells also decreased as IMP3 knockdown by using RNA interference in vitro. In summary, high expression of IMP3 in NB might contribute to the undifferentiated phenotype and invasive behaviors, leading to a poor prognosis. Determining IMP3 expression in NB could help to improve a personalized therapy. (Cancer Sci 2011; 102: 2191-2198 N euroblastoma (NB), a common cancer of early childhood that originates from primitive sympathetic neural precursors, has a remarkable heterogeneity of clinical behaviors ranging from spontaneous regression to rapid progression and death. Therapeutic options are proposed according to the Children's Oncology Group risk stratification criteria based on clinical and biological factors, including clinical stage, MYCN status, age at diagnosis, histology, and ploidy status.(1,2) Treatment strategy, which ranges from observation alone to intensive multimodal therapy, depends on the risk stratification of the patient in one of the three subgroups of low-, intermediate-, and high-risk of death. Although several biological and molecular prognostic factors have been identified, amplification of the MYCN oncogene, which occurs in roughly 20% of primary NB, is one of the most powerful prognostic factors in NB.(3) The co-opting neurotrophin pathways including the neurotrophin receptors (TrkA, TrkB, and TrkC) and their ligands (NGF, BDNF, and neurotrophin-3, respectively), which regulate the differentiation, apoptosis, and growth of neural cells, are also important prognosis-related factors in NB.(4) However, some patients with a normal MYCN copy number still present with clinically aggressive progression similar to those with MYCN-amplified tumors, suggesting that other unfavorable molecules determining inferior survival may exist.(5,6)The insulin-like growth factor II mRNA-binding protein 3 (IMP3), also known as L532S or K homology domain-containing protein overexpressed in cancer (KOC), is a member of the RNA-binding protein family that includes IMP1, IMP2...

Compositional abruptness of the interfaces is one of the important factors to determine the performance of Group IV semiconductor heterojunction (Si/Ge or Si/SiGe) nanowire devices. However, forming abrupt interfaces in the nanowires using the common vapor-liquid-solid (VLS) method is restricted because large solubility of Si and Ge in the Au eutectic liquid catalyst makes gradual composition change at the heterojunction after switching the gas phase components. According to the VLS growth mechanism, another possible approach to form an abrupt interface is making a change of the semiconductor concentration in the eutectic liquid before precipitation of the second phase. Here we show that the composition in AuSiGe eutectic liquid on SiGe nanowires of low Ge concentration (≤6%) can be altered by thermal oxidation at 700 °C. During the oxidation process, only Si is oxidized on the surface of the eutectic liquid, and the Ge/Si ratio in the eutectic liquid is increased. The subsequently precipitated SiGe step at the liquid/solid interface has a higher Ge concentration (∼20%), and a compositionally abrupt interface is produced in the nanowires. The growth mechanism of the heterojunction includes diffusion of Si and Ge atoms on nanowire surface into the AuSiGe eutectic liquid and step nucleation at the liquid/nanowire interface.

A stacking metal-insulator-semiconductor (MIS) solar cell structure, which integrates an n-type MIS solar cell with a p-type MIS solar cell, is proposed to effectively enlarge the open-circuit voltage (V oc ). The measured V oc is up to 0.71 V under simulated air mass 1.5 illumination (100 mW/cm 2 ). This V oc is larger than those of the n-type or p-type MIS solar cells with or without surface passivation. In this letter, we successfully demonstrate the feasibility of the V oc enhancement of MIS solar cells by using a stacking structure. Index Terms-Metal-insulator-semiconductor (MIS) solar cells, open-circuit voltage, photovoltaic devices, stacking solar cells.

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