In-sun Chu

Dr. In-sun Chu


Research Focus & Metrics

Academic Career Length

21Years (2006-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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30 November 2015 in Clinical Cancer Research
Verified
Journal Article
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SLSe-Ra Lee
Se-Ra Lee
YRYun-Gil Roh
Yun-Gil Roh
SKSeon-Kyu Kim
Seon-Kyu Kim
JLJu-Seog Lee
Ju-Seog Lee
SSSo-Young Seol
So-Young Seol
Sun-Hee LeemSun-Hee Leem
Sun-Hee Leem
Purpose: Previous study identified E2F1 as a key mediator of non–muscle-invasive bladder cancer (NMIBC) progression. The aim of this study was to identify the E2F1-related genes associated with poor prognosis and aggressive characteristics of bladder cancer. Experimental Design: Microarray analysis was performed to find E2F1-related genes associated with tumor progression and aggressiveness in the gene expression data from 165 primary patients with bladder cancer. The biologic activity of E2F1-related genes in tumor progression and aggressiveness was confirmed with experimental assays using bladder cancer cells and tumor xenograft assay. Results: The expression of E2F1 was significantly associated with EZH2 and SUZ12. The overexpression of E2F1, EZH2, and SUZ12 enhanced cancer progression including cell colony formation, migration, and invasiveness. Knockdown of these genes reduced motility, blocked invasion, and decreased tumor size in vivo. E2F1 bound the proximal EZH2 and SUZ12 promoter to activate transcription, suggesting that E2F1 and its downstream effectors, EZH2 and SUZ12, could be important mediators for the cancer progression. In addition, we confirmed an association between these genes and aggressive characteristics. Interestingly, the treatment of anticancer drugs to the cells overexpressing E2F1, EZH2, and SUZ12 induced the expression of CD44, KLF4, OCT4, and ABCG2 known as cancer stem cell (CSC)–related genes. Conclusions: The link between E2F1, EZH2, and/or SUZ12 revealed that E2f1 directly regulates transcription of the EZH2 and SUZ12 genes. The signature of E2F1–EZH2–SUZ12 shows a predictive value for prognosis in bladder tumors and the E2F1–EZH2–SUZ12–driven transcriptional events may regulate the cancer aggressiveness and chemo-resistance, which may provide opportunity for development of new treatment modalities. Clin Cancer Res; 21(23); 5391–403. ©2015 AACR.

14 November 2012 in BMC Cancer
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Journal Article
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NSNa Ri Shin
Na Ri Shin
EJEun Hui Jeong
Eun Hui Jeong
CCChang In Choi
Chang In Choi
HMHyun Jung Moon
Hyun Jung Moon
CKChae Hwa Kwon
Chae Hwa Kwon
DPDo Youn Park
Do Youn Park
Background: Epithelial–mesenchymal transition (EMT) plays a significant role in tumor progression and invasion. Snail is a known regulator of EMT in various malignant tumors. This study investigated the role of Snail in gastric cancer.Methods: We examined the effects of silenced or overexpressed Snail using lenti-viral constructs in gastric cancer cells. Immunohistochemical analysis of tissue microarrays from 314 patients with gastric adenocarcinoma (GC) was used to determine Snail’s clinicopathological and prognostic significance. Differential gene expression in 45 GC specimens with Snail overexpression was investigated using cDNA microarray analysis.Results: Silencing of Snail by shRNA decreased invasion and migration in GC cell lines. Conversely, Snail overexpression increased invasion and migration of gastric cancer cells, in line with increased VEGF and MMP11. Snail overexpression (≥75% positive nuclear staining) was also significantly associated with tumor progression (P < 0.001), lymph node metastases (P = 0.002), lymphovascular invasion (P = 0.002), and perineural invasion (P = 0.002) in the 314 GC patients, and with shorter survival (P = 0.023). cDNA microarray analysis revealed 213 differentially expressed genes in GC tissues with Snail overexpression, including genes related to metastasis and invasion.Conclusion: Snail significantly affects invasiveness/migratory ability of GCs, and may also be used as a predictive biomarker for prognosis or aggressiveness of GCs.

12 June 2014 in Clinical Cancer Research
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Journal Article
Open access
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SKSeon-Kyu Kim
Seon-Kyu Kim
YRYun-Gil Roh
Yun-Gil Roh
KPKiejung Park
Kiejung Park
Tae-Hong KangTae-Hong Kang
Tae-Hong Kang
WKWun-Jae Kim
Wun-Jae Kim
ICIn-sun Chu
In-sun Chu
Purpose: Although standard treatment with transurethral resection and intravesical therapy (IVT) is known to be effective to address the clinical behavior of non–muscle-invasive bladder cancer (NMIBC), many patients fail to respond to the treatment and frequently experience disease recurrence. Here, we aim to identify a prognostic molecular signature that predicts the NMIBC heterogeneity and response to IVT. Experimental Design: We analyzed the genomic profiles of 102 patients with NMIBC to identify a signature associated with disease recurrence. The validity of the signature was verified in three independent patient cohorts (n = 658). Various statistical methods, including a leave-one-out cross-validation and multivariate Cox regression analyses, were applied to identify a signature. We confirmed an association between the signature and tumor aggressiveness with experimental assays using bladder cancer cell lines. Results: Gene expression profiling in 102 patients with NMIBC identified a CCNB1 signature associated with disease recurrence, which was validated in another three independent cohorts of 658 patients. The CCNB1 signature was shown to be an independent risk factor by a multivariate analysis and subset stratification according to stage and grade [HR, 2.93; 95% confidence intervals (CI), 1.302–6.594; P = 0.009]. The subset analysis also revealed that the signature could identify patients who would benefit from IVT. Finally, gene network analyses and experimental assays indicated that NMIBC recurrence could be mediated by FOXM1–CCNB1–Fanconi anemia pathways. Conclusions: The CCNB1 signature represents a promising diagnostic tool to identify patients with NMIBC who have a high risk of recurrence and to predict response to IVT. Clin Cancer Res; 20(12); 3233–43. ©2014 AACR.

1 December 2019 in EBioMedicine
Verified
Journal Article
Open access
BSBic-Na Song
Bic-Na Song
SKSeon-Kyu Kim
Seon-Kyu Kim
JMJeong-Yeon Mun
Jeong-Yeon Mun
YCYoung Deuk Choi
Young Deuk Choi
Sun-Hee LeemSun-Hee Leem
Sun-Hee Leem
ICIn-sun Chu
In-sun Chu
Although various molecular subtypes of bladder cancer (BC) have been investigated, most of these studies have focused on muscle-invasive BC (MIBC). A few studies have investigated non-muscle-invasive BC (NMIBC) or NMIBC and MIBC together, but none has classified progressive NMIBC or immune checkpoint inhibitor (ICI)-based therapeutic responses in early-stage BC patients. A total of 1,934 samples from seven patient cohorts were used. We performed unsupervised hierarchical clustering to stratify patients into distinct subgroups and constructed a classifier by applying SAM/PAM algorithms. We then investigated the association between molecular subtypes and immunotherapy responsiveness using various statistical methods. We explored large-scale genomic datasets encompassing NMIBC and MIBC, redefining four distinct molecular subtypes, including a subgroup containing progressive NMIBC and MIBC with poor prognosis that would benefit from ICI treatment. This subgroup showed poor progression-free survival with the distinct features of high mutation load, activated cell cycle, and inhibited TGFβ signalling. Importantly, we verified that BC patients with this subtype were significantly responsive to an anti-PD-L1 agent in the IMvigor210 cohort. Our results reveal an immunotherapeutic option for ICI treatment of highly progressive NMIBC and MIBC with poor prognosis. This research was supported by the National Research Foundation of Korea grant funded by the Korean government, a grant from the Korea Health Technology R&D Project through the Korea Health Industry Development Institute, funded by the Ministry of Health and Welfare, Republic of Korea, and a grant from the KRIBB Research Initiative Program.

22 November 2010 in Genes, Chromosomes and Cancer
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Journal Article
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JYJu Dong Yang
Ju Dong Yang
ZSZhifu Sun
Zhifu Sun
CHChunling Hu
Chunling Hu
JLJinping Lai
Jinping Lai
RDRebecca Dove
Rebecca Dove
LRLewis R Roberts
Lewis R Roberts
The heparin‐degrading endosulfatases sulfatase 1 (SULF1) and sulfatase 2 (SULF2) have opposing effects in hepatocarcinogenesis despite structural similarity. Using mRNA expression arrays, we analyzed the correlations of SULF expression with signaling networks in human hepatocellular carcinomas (HCCs) and the associations of SULF expression with tumor phenotype and patient survival. Data from two mRNA microarray analyses of 139 and 36 HCCs and adjacent tissues were used as training and validation sets. Partek and Metacore software were used to identify SULF correlated genes and their associated signaling pathways. Associations between SULF expression, the hepatoblast subtype of HCC, and survival were examined. Both SULF1 and 2 had strong positive correlations with periostin, IQGAP1, TGFB1, and vimentin and inverse correlations with HNF4A and IQGAP2. Genes correlated with both SULFs were highly associated with the cell adhesion, cytoskeletal remodeling, blood coagulation, TGFB, and Wnt/β‐catenin and epithelial mesenchymal transition signaling pathways. Genes uniquely correlated with SULF2 were more associated with neoplastic processes than genes uniquely correlated with SULF1. High SULF expression was associated with the hepatoblast subtype of HCC. There was a bimodal effect of SULF1 expression on prognosis, with patients in the lowest or highest tertile having a worse prognosis than those in the middle tertile. SULFs have complex effects on HCC signaling and patient survival. There are functionally similar associations with cell adhesion, ECM remodeling, TGFB, and WNT pathways, but also unique associations of SULF1 and SULF2. The roles and targeting of the SULFs in cancer require further investigation.

8 February 2024 in Nature Communications
Verified
Journal Article
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SLSeong Eun Lee
Seong Eun Lee
SPSeongyeol Park
Seongyeol Park
SYShinae Yi
Shinae Yi
NCNa Rae Choi
Na Rae Choi
MLMi Ae Lim
Mi Ae Lim
YKYea Eun Kang
Yea Eun Kang
The role of the serine/glycine metabolic pathway (SGP) has recently been demonstrated in tumors; however, the pathological relevance of the SGP in thyroid cancer remains unexplored. Here, we perform metabolomic profiling of 17 tumor-normal pairs; bulk transcriptomics of 263 normal thyroid, 348 papillary, and 21 undifferentiated thyroid cancer samples; and single-cell transcriptomes from 15 cases, showing the impact of mitochondrial one-carbon metabolism in thyroid tumors. High expression of serine hydroxymethyltransferase-2 (SHMT2) and methylenetetrahydrofolate dehydrogenase 2 (MTHFD2) is associated with low thyroid differentiation scores and poor clinical features. A subpopulation of tumor cells with high mitochondrial one-carbon pathway activity is observed in the single-cell dataset. SHMT2 inhibition significantly compromises mitochondrial respiration and decreases cell proliferation and tumor size in vitro and in vivo. Collectively, our results highlight the importance of the mitochondrial one-carbon pathway in undifferentiated thyroid cancer and suggest that SHMT2 is a potent therapeutic target.