Publications by authors named "Ensel Oh"

Solitary fibrous tumors (SFTs) are NAB2-STAT6 fusion-associated neoplasms. There are several subtypes of NAB2-STAT6 fusions, but their clinical significances are still unclear. Moreover, the mechanisms of malignant progression are also poorly understood.

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Triple-negative breast cancer (TNBC) is an aggressive breast cancer subtype characterized by poor patient prognosis and for which no targeted therapies are currently available. TNBC can be further categorized as either basal-like (BLBC) or quintuple-negative breast cancer (QNBC). In the present study, we aimed to identify novel molecular therapeutic targets for TNBC by analyzing the mRNA expression of TNBC-related genes in publicly available microarray data sets.

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Gastric cancer (GC), one of the most common cancers worldwide, has a high mortality rate due to limited treatment options. Identifying novel and promising molecular targets is a major challenge that must be overcome if treatment of advanced GC is to be successful. Here, we used comparative genomic hybridization and gene expression microarrays to examine genome-wide DNA copy number alterations (CNAs) and global gene expression in 38 GC samples from old and young patients.

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Triple-negative breast cancer is characterized by the absence of estrogen and progesterone receptors and human epidermal growth factor receptor 2, and is associated with a poorer outcome than other subtypes of breast cancer. Moreover, there are no accurate prognostic genes or effective therapeutic targets, thereby necessitating continued intensive investigation. This study analyzed the genetic mutation landscape in 70 patients with triple-negative breast cancer by targeted exome sequencing of tumor and matched normal samples.

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Dermatofibrosarcoma protuberans (DFSP) is a very rare soft tissue sarcoma, generally of low-grade malignancy. DFSP is locally aggressive with a high recurrence rate, but metastasis occurs rarely. To investigate the mechanism of metastasis in DFSP, we analyzed the whole exome sequencing data of serial tumor samples obtained from a patient who had a 10-year history of recurrent and metastatic DFSP.

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Girdin is an actin-binding Akt substrate that is an integral component of the PI3K/Akt signalling pathway. However, the clinicopathological significance of Girdin expression in breast cancer has not been clarified. The purpose of this study was to characterise the clinicopathological implication of Girdin expression in breast cancer.

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Background: Patient-derived xenograft (PDX) models are important tools in precision medicine and for the development of targeted therapies to treat cancer patients. This study aimed to evaluate our precision medicine strategy that integrates genomic profiling and preclinical drug-screening platforms, in order to personalize cancer treatments using PDX models.

Methods: We performed array-comparative genomic hybridization, microarray, and targeted next-generation sequencing analyses, in order to determine the oncogenic driver mutations.

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Mesenchymal-type cancers after epithelial mesenchymal transition (EMT) were recently shown to acquire chemoresistance through expressing EMT specific transcription factors. However, druggable (or actionable) target(s) for chemoresistance in mesenchymal-type lung cancers remain unidentified. Here, we used a public clinical genomic database and mesenchymal lung cancer cells (MLCC) model derived from the A549 lung adenocarcinoma cell line to demonstrate that BCL2 expression, which is highly induced in mesenchymal-type lung cancers, as a predictor of poor prognosis in mesenchymal lung cancer patients and association with acquired chemoradioresistance.

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Introduction: Response to mesenchymal-epithelial transition (MET) inhibitors in NSCLC with mesenchymal-epithelial transition gene (MET) exon 14 skipping (METex14) has fueled molecular screening efforts and the search for optimal therapies. However, further work is needed to refine the clinicopathologic and prognostic implications of METex14 skipping.

Methods: Among 795 East Asian patients who underwent a surgical procedure for NSCLC, we screened 45 patients with quintuple-negative (EGFR-negative/KRAS-negative/anaplastic lymphoma kinase gene [ALK]-negative/ROS1-negative/ret proto-oncogene [RET]-negative) lung adenocarcinomas by using reverse-transcriptase polymerase chain reaction and found 17 patients (37.

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Therapies targeting SRC family kinases (SFKs) have shown efficacy in treating non-small cell lung cancer (NSCLC). However, recent clinical trials have found that the SFK inhibitor dasatinib is ineffective in some patient cohorts. Regardless, dasatinib treatment may benefit some NSCLC patient subgroups.

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Introduction: The incidence rate of lung adenocarcinoma (LUAD), the predominant histological subtype of lung cancer, is elevated in Asians, particularly in female nonsmokers. The mutation patterns in LUAD in Asians might be distinct from those in LUAD in whites.

Methods: We profiled 271 resected LUAD tumors (mainly stage I) to characterize the genomic landscape of LUAD in Asians with a focus on female nonsmokers.

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Aims: We compared four common methods for measuring DNA methylation levels and recommended the most efficient method in terms of cost and coverage.

Materials & Methods: The DNA methylation status of liver and stomach tissues was profiled using four different methods, whole-genome bisulphite sequencing (WG-BS), targeted bisulphite sequencing (Targeted-BS), methylated DNA immunoprecipitation sequencing (MeDIP-seq) and methylated DNA immunoprecipitation bisulphite sequencing (MeDIP-BS). We calculated DNA methylation levels using each method and compared the results.

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Chronic exposure to TGFβ, a frequent occurrence for tumor cells in the tumor microenvironment, confers more aggressive phenotypes on cancer cells by promoting their invasion and migration while at the same time increasing their resistance to the growth-inhibitory effect of TGFβ. In this study, a transdifferentiated (TD) A549 cell model, established by chronically exposing A549 cells to TGFβ, showed highly invasive phenotypes in conjunction with attenuation of Smad-dependent signaling. We show that Snail protein, the mRNA expression of which strongly correlates with a poor prognosis in lung cancer patients, was highly stable in TD cells after TGFβ stimulation.

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Malignant pheochromocytoma/paraganglioma (PCC/PGL) is defined by the presence of metastases at non-chromaffin sites, which makes it difficult to prospectively diagnose malignancy. Here, we performed array CGH (aCGH) and paired gene expression profiling of fresh, frozen PCC/PGL samples (n = 12), including three malignant tumors, to identify genes that distinguish benign from malignant tumors. Most PCC/PGL cases showed few copy number aberrations, regardless of malignancy status, but mRNA analysis revealed that 390 genes were differentially expressed in benign and malignant tumors.

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Formalin fixing with paraffin embedding (FFPE) has been a standard sample preparation method for decades, and archival FFPE samples are still very useful resources. Nonetheless, the use of FFPE samples in cancer genome analysis using next-generation sequencing, which is a powerful technique for the identification of genomic alterations at the nucleotide level, has been challenging due to poor DNA quality and artificial sequence alterations. In this study, we performed whole-exome sequencing of matched frozen samples and FFPE samples of tissues from 4 cancer patients and compared the next-generation sequencing data obtained from these samples.

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While metastasis, the main cause of lung cancer-related death, has been extensively studied, the underlying molecular mechanism remains unclear. A previous clinicogenomic study revealed that expression of N-acetylgalactosaminyltransferase (GalNAc-T14), is highly inversely correlated with recurrence-free survival in those with non-small cell lung cancer (NSCLC). However, the underlying molecular mechanism(s) has not been determined.

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Surgery and radiation are the current standard treatments for cervical cancer. However, there is no effective therapy for metastatic or recurrent cases, necessitating the identification of therapeutic targets. In order to create preclinical models for screening potential therapeutic targets, we established 14 patient-derived xenograft (PDX) models of cervical cancers using subrenal implantation methods.

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MET, a cell surface receptor for hepatocyte growth factor, is involved in the development of triple-negative/basal-like breast cancer (TNBC/BLBC). However, its utility as a therapeutic target in this subtype of breast cancer is poorly understood. To evaluate MET fully as a potential therapeutic target for TNBC/BLBC, we investigated the relationship between MET expression and clinical outcomes of patients with breast cancer and the functional effect of MET inhibition.

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Introduction: The most common mechanism underlying overexpression and activation of anaplastic lymphoma kinase (ALK) in non-small-cell lung carcinoma could be attributed to the formation of a fusion protein. To date, five fusion partners of ALK have been reported, namely, echinoderm microtubule associated protein like 4, tropomyosin-related kinase-fused gene, kinesin family member 5B, kinesin light chain 1, and protein tyrosine phosphatase, nonreceptor type 3.

Methods: In this article, we report a novel fusion gene huntingtin interacting protein 1 (HIP1)-ALK, which is conjoined between the huntingtin-interacting protein 1 gene HIP1 and ALK.

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Rhabdomyosarcoma (RMS) is the most commonly occurring type of soft tissue tumor in children. However, it is rare in adults, and therefore, very little is known about the most appropriate treatment strategy for adult RMS patients. We performed genomic analysis of RMS cells derived from a 27-year-old male patient whose disease was refractory to treatment.

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Background: Despite significant improvements in colon cancer outcomes over the past few decades, preclinical development of more effective therapeutic strategies is still limited by the availability of clinically relevant animal models. To meet those clinical unmet needs, we generated a well-characterized in vivo preclinical platform for colorectal cancer using fresh surgical samples.

Methods: Primary and metastatic colorectal tumor tissues (1-2 mm(3)) that originate from surgery were implanted into the subcutaneous space of nude mice and serially passaged in vivo.

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Specificity protein 1 (SP1) is an essential transcription factor that regulates multiple cancer-related genes. Because aberrant expression of SP1 is related to cancer development and progression, we focused on SP1 expression in gastric carcinoma and its correlation with disease outcomes. Although patient survival decreased as SP1 expression increased (P<0.

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A model for a more precise prognosis of the risk of relapse is needed to avoid overtreatment of lymph node-negative breast cancer patients. A large derivation data set (n = 684) was generated by pooling three independent breast cancer expression microarray data sets. Two major prognostic factors, proliferation and immune response, were identified among genes showing significant differential expression levels between the good outcome and poor outcome groups.

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Background: Triple-negative breast cancers (TNBCs) and basal-like breast cancers (BLBCs) are known as poor outcome subtypes with a lack of targeted therapy. Previous studies have shown conflicting results regarding the difference of prognostic significance between TNBCs and BLBCs. In this study, we aimed to characterize the prognostic features of TNBCs, in view of BLBCs and quintuple-negative breast cancers (QNBC/5NPs).

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Normalization of mRNA levels using endogenous reference genes (ERGs) is critical for an accurate comparison of gene expression between different samples. Despite the popularity of traditional ERGs (tERGs) such as GAPDH and ACTB, their expression variability in different tissues or disease status has been reported. Here, we first selected candidate housekeeping genes (HKGs) using human gene expression data from different platforms including EST, SAGE, and microarray, and 13 novel ERGs (nERGs) (ARL8B, CTBP1, CUL1, DIMT1L, FBXW2, GPBP1, LUC7L2, OAZ1, PAPOLA, SPG21, TRIM27, UBQLN1, ZNF207) were further identified from these HKGs.

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