Cheol Kwak

Cheol Kwak


Research Focus & Metrics

Academic Career Length

25Years (2002-Present)

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

Representative Publications

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15 November 2024 in Nature Communications
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HCHyunsik Choi
Hyunsik Choi
SJSeung-Hwan Jeong
Seung-Hwan Jeong
CSCristina Simó
Cristina Simó
ABAnna Bakenecker
Anna Bakenecker
JLJordi Liop
Jordi Liop
Sei Kwang HahnSei Kwang Hahn
Sei Kwang Hahn
Most non-muscle invasive bladder cancers have been treated by transurethral resection and following intravesical injection of immunotherapeutic agents. However, the delivery efficiency of therapeutic agents into bladder wall is low due to frequent urination, which leads to the failure of treatment with side effects. Here, we report a urease-powered nanomotor containing the agonist of stimulator of interferon genes (STING) for the efficient activation of immune cells in the bladder wall. After characterization, we perform in vitro motion analysis and assess in vivo swarming behaviors of nanomotors. The intravesical instillation results in the effective penetration and retention of nanomotors in the bladder. In addition, we confirm the anti-tumor effect of nanomotor containing the STING agonist (94.2% of inhibition), with recruitment of CD8+ T cells (11.2-fold compared with PBS) and enhanced anti-tumor immune responses in bladder cancer model in female mice. Furthermore, we demonstrate the better anti-tumor effect of nanomotor containing the STING agonist than those of the gold standard Bacille Calmette-Guerin therapy and the anti-PD-1 inhibitor pembrolizumab in bladder cancer model. Taken together, the urease-powered nanomotor would provide a paradigm as a next-generation platform for bladder cancer immunotherapy.

11 May 2012 in BJU International
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YPYong Hyun Park
Yong Hyun Park
KBKyung Don Baik
Kyung Don Baik
YLYoung Ju Lee
Young Ju Lee
JKJa Hyeon Ku
Ja Hyeon Ku
HKHyeon Hoe Kim
Hyeon Hoe Kim
CKCheol Kwak
Cheol Kwak

2 June 2015 in BMC Cancer
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JKJa Hyun Ku
Ja Hyun Ku
MKMinyong Kang
Minyong Kang
HKHyung Suk Kim
Hyung Suk Kim
CJChang Wook Jeong
Chang Wook Jeong
CKCheol Kwak
Cheol Kwak
HKHyeon-Hoe Kim
Hyeon-Hoe Kim
Although lymph node (LN) status and the LN burden determine the outcome of bladder cancer patients treated with cystectomy, compelling arguments have been made for the incorporation of LN density into the current staging system. Here, we investigate the relationship between LN density and clinical outcome in patients with LN-positive disease, following radical cystectomy for bladder cancer. PubMed, SCOPUS, the Institute for Scientific Information Web of Science, and the Cochrane Library were searched to identify relevant published literature. Fourteen studies were included in the meta-analysis, with a total number of 3311 patients. Of these 14 publications, 6 studies, (533 patients), 10 studies (2966 patients), and 5 studies (1108 patients) investigated the prognostic association of LN density with disease-free survival (DFS), disease-specific survival (DSS), and overall survival (OS), respectively. The pooled hazard ratio (HR) for DFS was 1.45 (95 % confidence interval [CI], 1.10–1.91) without heterogeneity (I2 = 0 %, p = 0.52). Higher LN density was significantly associated with poor DSS (pooled HR, 1.53; 95 % CI, 1.23–1.89). However, significant heterogeneity was found between studies (I2 = 66 %, p = 0.002). The pooled HR for OS was statistically significant (pooled HR, 1.45; 95 % CI, 1.11–1.90) without heterogeneity (I2 = 42 %, p = 0.14). The results of the Begg and Egger tests suggested that publication bias was not evident in this meta-analysis. The data from this meta-analysis indicate that LN density is an independent predictor of clinical outcome in LN-positive patients. LN density may be useful in future staging systems, thus allowing better prognostic classification of LN-positive bladder cancer.

1 December 2014 in International braz j urol
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JKJa Hyeon Ku
Ja Hyeon Ku
MKMyong Kim
Myong Kim
WCWoo Suk Choi
Woo Suk Choi
CKCheol Kwak
Cheol Kwak
HKHyeon Hoe Kim
Hyeon Hoe Kim
Key words: Carcinoma; Transitional Cell; Urinary Tract; Ureter; C-Reactive Protein; Inflammation

9 October 2018 in International Journal of Cancer
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KLKyoung‐Hwa Lee
Kyoung‐Hwa Lee
SHSeokbong Hong
Seokbong Hong
MKMinyong Kang
Minyong Kang
CJChang Wook Jeong
Chang Wook Jeong
JKJa Hyeon Ku
Ja Hyeon Ku
CKCheol Kwak
Cheol Kwak

Verified
Journal Article
Open access
PDF file
MKMinyong Kang
Minyong Kang
CJChang Wook Jeong
Chang Wook Jeong
JKJa Hyun Ku
Ja Hyun Ku
CKCheol Kwak
Cheol Kwak
HKHyeon-Hoe Kim
Hyeon-Hoe Kim
Statins are cholesterol reduction agents that exhibit anti-cancer activity in several human cancers. Because autophagy is a crucial survival mechanism for cancer cells under stress conditions, cooperative inhibition of autophagy acts synergistically with other anti-cancer drugs. Thus, this study investigates whether combined treatment of atorvastatin and autophagy inhibitors results in enhancing the cytotoxic effects of atorvastatin, upon human bladder cancer cells, T24 and J82, in vitro. To measure cell viability, we performed the EZ-Cytox cell viability assay. We examined apoptosis by flow cytometry using annexin-V/propidium iodide (PI and western blot using procaspase-3 and poly (ADP-ribose) polymerase (PARP) antibodies. To examine autophagy activation, we evaluated the co-localization of LC3 and LysoTracker by immunocytochemistry, as well as the expression of LC3 and p62/sequestosome-1 (SQSTM1) by western blot. In addition, we assessed the survival and proliferation of T24 and J82 cells by a clonogenic assay. We found that atorvastatin reduced the cell viability of T24 and J82 cells via apoptotic cell death and induced autophagy activation, shown by the co-localization of LC3 and LysoTracker. Moreover, pharmacologic inhibition of autophagy significantly enhanced atorvastatin-induced apoptosis in T24 and J82 cells. In sum, inhibition of autophagy potentiates atorvastatin-induced apoptotic cell death in human bladder cancer cells in vitro, providing a potential therapeutic approach to treat bladder cancer.