16 research outputs found

    Riding the wave: Distributional properties and process explanations of merger and acquisition waves

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    Although Mergers and Acquisitions (M&A) are potential value-creation opportunities, why they tend to occur in waves is a mystery to scholars and managers alike. Most models of M&A waves are unilevel, reductionist, and Gaussian, whereas wave patterns are arguably multi-level, emergent, and non-normally distributed. Using complexity theory, I interpret waves as emergent expressions of a self-organized critical ecology of firms conceptualized as a complex adaptive system. My observation that aggregate U.S. M&A waves from 1895 to 2008 are power-law-distributed lends support. The view that waves are self-organized critical phenomena, similar to earthquakes and avalanches, facilitates integration of prior wave theories. I then employ process-tracing to generate a historical narrative of the Great Merger Wave of 1898-1903, from which I obtain a robust process for waves consistent with a CAS interpretation of these phenomena: (1) a privatizing, market-expanding and financially innovating transportation network generates (2a) laissez-faire regulation, (2b) economic competition, and (2c) financial arbitrage, leading to (3) a burst of consolidation. My process explanation explains the power law's emergence, and may help to understand better the process dynamics of M&A waves

    Genome-wide association study of lung adenocarcinoma in East Asia and comparison with a European population.

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    Lung adenocarcinoma is the most common type of lung cancer. Known risk variants explain only a small fraction of lung adenocarcinoma heritability. Here, we conducted a two-stage genome-wide association study of lung adenocarcinoma of East Asian ancestry (21,658 cases and 150,676 controls; 54.5% never-smokers) and identified 12 novel susceptibility variants, bringing the total number to 28 at 25 independent loci. Transcriptome-wide association analyses together with colocalization studies using a Taiwanese lung expression quantitative trait loci dataset (n = 115) identified novel candidate genes, including FADS1 at 11q12 and ELF5 at 11p13. In a multi-ancestry meta-analysis of East Asian and European studies, four loci were identified at 2p11, 4q32, 16q23, and 18q12. At the same time, most of our findings in East Asian populations showed no evidence of association in European populations. In our studies drawn from East Asian populations, a polygenic risk score based on the 25 loci had a stronger association in never-smokers vs. individuals with a history of smoking (Pinteraction = 0.0058). These findings provide new insights into the etiology of lung adenocarcinoma in individuals from East Asian populations, which could be important in developing translational applications

    Genome-wide association study of lung adenocarcinoma in East Asia and comparison with a European population

    Get PDF
    Lung adenocarcinoma is the most common type of lung cancer. Known risk variants explain only a small fraction of lung adenocarcinoma heritability. Here, we conducted a two-stage genome-wide association study of lung adenocarcinoma of East Asian ancestry (21,658 cases and 150,676 controls; 54.5% never-smokers) and identified 12 novel susceptibility variants, bringing the total number to 28 at 25 independent loci. Transcriptome-wide association analyses together with colocalization studies using a Taiwanese lung expression quantitative trait loci dataset (n = 115) identified novel candidate genes, including FADS1 at 11q12 and ELF5 at 11p13. In a multi-ancestry meta-analysis of East Asian and European studies, four loci were identified at 2p11, 4q32, 16q23, and 18q12. At the same time, most of our findings in East Asian populations showed no evidence of association in European populations. In our studies drawn from East Asian populations, a polygenic risk score based on the 25 loci had a stronger association in never-smokers vs. individuals with a history of smoking (P interaction  = 0.0058). These findings provide new insights into the etiology of lung adenocarcinoma in individuals from East Asian populations, which could be important in developing translational applications

    Identification of Genomic and Molecular Traits that Present Therapeutic Vulnerability to HGF-targeted therapy in Glioblastoma.

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    Background: Cancer is a complex disease with profound genomic alterations and extensive heterogeneity. Recent studies on a large-scale genomics have shed lights on the impact of core oncogenic pathways which are frequently dysregulated in a wide spectrum of cancer types. Aberrant activation of hepatocyte growth factor (HGF) signaling axis has been associated with promoting various oncogenic programs during tumor initiation, progression, and treatment resistance. As a result, HGF-targeted therapy has emerged as an attractive therapeutic approach. However, recent clinical trials involving HGF-targeted therapies have demonstrated rather disappointing results. Thus, an alternative, in-depth assessment of new patient stratification is necessary to shift the current clinical course. Methods: To address such challenges, we have evaluated therapeutic efficacy of YYB-101, a HGF neutralizing antibody, in a series of primary glioblastoma stem cells (GSCs) both in vitro and in vivo. Furthermore, we performed genome and transcriptome analysis to determine genetic and molecular traits that exhibit vulnerability to HGF-mediated therapy. Results: We have identified differentially expressed genes, including MET, KDR, and SOX3 which are associated with tumor invasiveness, malignancy, and unfavorable prognosis in glioblastoma patients. We also demonstrated HGF-MET signaling axis as a key molecular determinant in GSC invasion and also discovered that a significant association in HGF expression existed between mesenchymal phenotype and immune cell recruitment. Conclusions: Up-regulation of MET and mesenchymal cellular state are essential in generating HGF-mediated therapeutic responses. Our results provide an important framework for evaluating HGF-targeted therapy in future clinical settings

    Association between GWAS-identified lung adenocarcinoma susceptibility loci and EGFR mutations in never-smoking Asian women, and comparison with findings from Western populations

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    To evaluate associations by EGFR mutation status for lung adenocarcinoma risk among never-smoking Asian women, we conducted a meta-analysis of 11 loci previously identified in genome-wide association studies (GWAS). Genotyping in an additional 10,780 never-smoking cases and 10,938 never-smoking controls from Asia confirmed associations with eight known single nucleotide polymorphisms (SNPs). Two new signals were observed at genome-wide significance (P < 5 × 10-8), namely, rs7216064 (17q24.3, BPTF), for overall lung adenocarcinoma risk, and rs3817963 (6p21.3, BTNL2) which is specific to cases with EGFR mutations. In further sub-analyses by EGFR status, rs9387478 (ROS1/DCBLD1) and rs2179920 (HLA-DPB1) showed stronger estimated associations in EGFR-positive compared to EGFR-negative cases. Comparison of the overall associations with published results in Western populations revealed that the majority of these findings were distinct, underscoring the importance of distinct contributing factors for smoking and non-smoking lung cancer. Our results extend the catalogue of regions associated with lung adenocarcinoma in non-smoking Asian women and highlight the importance of how the germline could inform risk for specific tumour mutation patterns, which could have important translational implications
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