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With 100-nm-thick 3C-SiC intermediate layer, GaN layer of relative high quality was obtained on Si substrate by using a maskless epitaxial lateral overgrowth (ELO). The three-dimensional growth of maskless ELO process was investigated with wafer reflectance collected during growth. Low temperature cathodoluminescence observation confirmed the improvement of the GaN quality by ELO. An AlN interlayer was used to prevent crack of the GaN epilayer. As a result, the as-grown GaN layer shows a crack-free surface with long atomic steps. The threading dislocation density is lower than 1 × 109 cm−2 in GaN layer underneath AlN interlayer. [ABSTRACT FROM AUTHOR]

Background:To elucidate clinicopathological characteristics of non-small-cell lung carcinoma (NSCLC) cases carrying RET rearrangements causing oncogenic fusions to identify responders to therapy with RET tyrosine kinase inhibitors.Methods:We investigated 1874 patients with carcinomas, including 1620 adenocarcinomas (ADCs), 203 squamous cell carcinomas (SCCs), 8 large cell carcinomas, and 43 sarcomatoid carcinomas (SACs). Fluorescence in situ hybridisation (FISH) and/or reverse transcription-PCR (RT-PCR) were performed to detect RET gene rearrangement.Results:In all, 22 cases (1.2%) showed RET rearrangements; all cases were of ADC histology. Of the 22 patients, 19 possessed KIF5B-RET fusion genes, whereas 3 possessed CCDC6-RET fusion genes. The RET-rearranged tumours were significantly more common in younger patients (P=0.038) and tended to occur in patients with no history of smoking (P=0.051). In addition, RET rearrangements were not associated with gender, occupational history (particularly radioactive exposure), tumour size, lymph node status, tumour stage, or patient survival. The predominant growth pattern in RET-rearranged ADCs was lepidic in 6 cases, papillary in 9 cases, acinar in 2 cases, micropapillary in 1 case, and solid in 4 cases. Cells with cytoplasmic mucin production were at least focally present in 12 of the 22 (54.5%) RET-rearranged ADC cases. Among the 21 analysed RET-rearranged tumours, RET immunopositivity was observed in 15 cases (71.4%), and was significantly associated with RET rearrangement (P<0.001).Conclusions:The RET rearrangements were observed in 1.2% of NSCLCs. All cases of RET rearrangement were ADCs. The RET rearrangements were more likely to be observed in younger patients. Although cytoplasmic mucin production was at least focally present in 54.5% of RET-rearranged ADCs, specific histological features were not detected. [ABSTRACT FROM AUTHOR]

Lung cancer shows diverse histological subtypes. Large-cell neuroendocrine cell carcinoma and small-cell lung carcinoma show similar histological features and clinical behaviors, and can be classified as high-grade neuroendocrine carcinoma (HGNEC) of the lung. Here we elucidated the molecular classification of pulmonary endocrine tumors by copy-number profiling. We compared alterations of copy number with the clinical outcome of HGNEC and identified a chromosomal gain of the DEK oncogene locus (6p22.3) that was significantly associated with poor prognosis. We further confirmed that DEK overexpression was associated with poor prognosis in a larger set of HGNEC. Downregulation of DEK by small hairpin RNA led to a marked reduction of in vitro colony formation, in vivo tumorigenicity and chemo-resistance, and was associated with loss of lung cancer stem cell markers. Gene expression profiling revealed that DEK downregulation was associated with altered expression of transcriptional regulators, which specifically include known targets of interchromosomal translocations in hematopoietic tumors, and knockdown of these epigenetic modifiers affected colony formation activity. Our study showed that DEK overexpression, partly through an increase in its gene dose, mediates the activity of global transcriptional regulators and is associated with tumor initiation activity and poor prognosis in HGNEC. [ABSTRACT FROM AUTHOR]

Preoperative chemotherapy is a promising strategy in patients with early-stage resectable non-small-cell lung cancer (NSCLC); optimal chemotherapy remains unclear. Clinical (c-) stage IB/II NSCLC patients were randomised to receive either two cycles of docetaxel (D)-cisplatin (P) combination chemotherapy (D 60 mg m(-2) and P 80 mg m(-2) on day 1) every 3-4 weeks or three cycles of D monotherapy (70 mg m(-2)) every 3weeks. Thoracotomy was performed 4-5 weeks (DP) or 3-4 weeks (D) after chemotherapy. The primary end point was 1-year disease-free survival (DFS). From October 2002 to November 2003, 80 patients were randomised. Chemotherapy toxicities were mainly haematologic and well tolerated. There were two early postoperative deaths with DP (one intraoperative bleeding and one empyema). Pathologic complete response was observed in two DP patients. Docetaxel-cisplatin was superior to D in terms of response rate (45 vs 15%) and complete resection rate (95 vs 87%). Both DFS and overall survival were better in DP. Disease-free survival at 1, 2 and 4 years were 78, 65 and 57% with DP, and were 62, 44 and 36% with D, respectively. Preoperative DP was associated with encouraging resection rate and DFS data, and phase III trials for c-stage IB/II NSCLC are warranted. [ABSTRACT FROM AUTHOR]

Background and Objectives Many sequences of variants in the ABO blood group system have been analysed, but genetic information is not available on the rare Am phenotype blood group. We isolated the Am phenotype in one family and performed molecular analysis on this allele. Materials and Methods Exons 6 and 7 of the ABO gene were analysed using genomic DNAs from members of one family containing Am phenotype individuals via polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP) and DNA sequencing. Results In the Am allele, two single base substitutions were detected compared with the A101 allele. Both were C → T mutations at nucleotide positions 467 and 761. PCR–RFLP using the Acc I restriction enzyme was performed to detect the Am allele in 214 samples that had already been determined as type A or O by serological tests, but no sample was found to contain an Am allele. Conclusions In this study a new allele with a single-base substitution at nucleotide position 761 was identified in the Am phenotype. We designated this new allele as A112 (according to the guidelines for human gene nomenclature) and determined that PCR–RFLP analysis using the Acc I restriction enzyme will be useful for detecting this allele. [ABSTRACT FROM AUTHOR]

In this work, the stress distribution of a thick GaN layer, which was realized with multiple AlN interlayers (ILs) on a 3C-SiC/Si (1 1 1) substrate, was mapped by low-temperature cathodoluminescence spectroscopy. A relaxation of compressive stress was distinguished in the top GaN layers above the AlN ILs by the inhomogeneous luminescent property. Through cross-sectional transmission electron microscopy, misfit dislocations (MDs) transformed from threading dislocations were observed. Analysis confirmed that the transformation process of dislocations should account for a part of compressive stress relaxation. As a result, a trade-off between compressive stress induction and dislocation transformation effects, both of which were induced by the AlN ILs, was proposed. In this model, the mean length of MDs in the GaN/AlN multi-layer structure was evaluated as L = 84 nm. [ABSTRACT FROM AUTHOR]