Joong Bae Ahn

Dr. Joong Bae Ahn


Research Focus & Metrics

Academic Career Length

57Years (1970-Present)

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

Representative Publications

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27 February 2008 in Annals of Oncology
Verified
Journal Article
Open access
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SCS. H. Cheon
S. H. Cheon
SRSun Young Rha
Sun Young Rha
HJH.-C. Jeung
H.-C. Jeung
CIC.-K. Im
C.-K. Im
SKS. H. Kim
S. H. Kim
HCHyun Cheol Chung
Hyun Cheol Chung
Background: The benefit of surgical resection of liver metastases from gastric cancer has not been well established. The aim of this study was to evaluate the rationale for hepatic resection in patients with hepatic metastases from gastric cancer. Methods: Among 10 259 patients diagnosed with gastric adenocarcinoma in the Yonsei University Health System from 1995 to 2005, we reviewed the records of 58 patients with liver-only metastases from gastric cancer who underwent gastric resection regardless of hepatic surgery. Results: The overall 1-year, 3-year, and 5-year survival rates of 41 patients who underwent hepatic resection with curative intent were 75.3%, 31.7%, and 20.8%, respectively, and three patients survived >7 years. Of the 41 patients, 22 had complete resection and 19 had palliative resection. Between the curative and palliative resections, survival rates after curative intent were not different. The number of liver metastasis (solitary or multiple) was a marginally significant prognostic factor for survival. Conclusions: Surgery for liver metastases arising from gastric adenocarcinoma is reasonable if complete resection seems feasible after careful preoperative staging, even if complete resection is not actually achieved. Hepatic resection should be considered as an option for gastric cancer patients with hepatic metastases.

26 May 2016 in British Journal of Cancer
Verified
Journal Article
Open access
CKChang Gon Kim
Chang Gon Kim
JAJoong Bae Ahn
Joong Bae Ahn
MJMin Kyu Jung
Min Kyu Jung
SBSeung Hoon Beom
Seung Hoon Beom
CKChan Kim
Chan Kim
SSSang Joon Shin
Sang Joon Shin
The BJC is owned by Cancer Research UK, a charity dedicated to understanding the causes, prevention and treatment of cancer and to making sure that the best new treatments reach patients in the clinic as quickly as possible. The journal reflects these aims. It was founded more than fifty years ago and, from the start, its far-sighted mission was to encourage communication of the very best cancer research from laboratories and clinics in all countries. The breadth of its coverage, its editorial independence and it consistent high standards, have made BJC one of the world's premier general cancer journals. Its increasing popularity is reflected by a steadily rising impact factor.

1 May 2017 in Annals of Surgery
Verified
Journal Article
Open access
HCHong Jae Chon
Hong Jae Chon
WHWoo Jin Hyung
Woo Jin Hyung
CKChan Kim
Chan Kim
SPSohee Park
Sohee Park
JKJie-Hyun Kim
Jie-Hyun Kim
HJHei-Cheul Jeung
Hei-Cheul Jeung
The aim of this study was to analyze the clinicopathologic characteristics and prognosis of signet ring cell carcinoma (SRC) according to disease status (early vs advanced gastric cancer) in gastric cancer patients. The prognostic implication of gastric SRC remains a subject of debate. A retrospective analysis was performed using the clinical records of 7667 patients including 1646 SRC patients who underwent radical gastrectomy between 2001 and 2010. A further analysis was also performed after dividing patients into three groups according to histologic subtype: SRC, well-to-moderately differentiated (WMD), and poorly differentiated adenocarcinoma. SRC patients have younger age distribution and female predominance compared with other histologic subtypes. Notably, the distribution of T stage of SRC patients was distinct, located in extremes (T1: 66.2% and T4: 20%). Moreover, the prognosis of SRC in early gastric cancer and advanced gastric cancer was contrasting. In early gastric cancer, SRC demonstrated more favorable prognosis than WMD after adjusting for age, sex, and stage. In contrast, SRC in advanced gastric cancer displayed worse prognosis than WMD. As stage increased, survival outcomes of SRC continued to worsen compared with WMD. Although conferring favorable prognosis in early stage, SRC has worse prognostic impact as disease progresses. The longstanding controversy of SRC on prognosis may result from disease status at presentation, which leads to differing prognosis compared with tubular adenocarinoma.

8 July 2016 in BMC Cancer
Verified
Journal Article
Open access
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CKChan Kim
Chan Kim
EKEun Kyung Kim
Eun Kyung Kim
HJHun Jung
Hun Jung
HCHong Jae Chon
Hong Jae Chon
JHJung Woo Han
Jung Woo Han
HKHyo Song Kim
Hyo Song Kim
The PD-1/PD-L1 axis plays a paramount role in the immune escape of tumor cells by negative regulation of T-cell functions. The aim of the present study was to characterize the PD-L1 expression pattern and its clinical implication in soft-tissue sarcomas (STS). We analyzed PD-L1 expression in 82 STS patients with 5 subtypes: rhabdomyosarcoma, synovial sarcoma, Ewing sarcoma, epithelioid sarcoma, and mesenchymal chondrosarcoma. The median age at diagnosis was 26 (range: 1–78) and the male to female ratio was 1.6. The majority (80 %) of patients showed locoregional disease rather than metastatic disease at diagnosis. Thirty-five cases (43 %) showed PD-L1 expression and the proportion of PD-L1 expression was significantly different according to histologic subtypes (P = 0.004); highest in epithelioid sarcoma (100 %, 7/7), followed by synovial sarcoma (53 %, 10/19), rhabdomyosarcoma (38 %, 12/32), and Ewing sarcoma (33 %, 6/18), while it was not expressed in mesenchymal chondrosarcoma (0 %, 0/6). STS patients with PD-L1 expression had worse overall survival compared with those without PD-L1 expression (5-year survival rate: 48 % vs. 68 %, P = 0.015). The Cox proportional hazard model adjusted for histologic subtype, initial metastasis, and PD-L1 expression showed that PD-L1 expression was significantly associated with shorter overall survival (P = 0.037, HR 2.57, 95 % CI 1.060–6.231). We have confirmed PD-L1 expression in various STS of young population and demonstrated its independent negative prognostic role, thereby suggesting the PD-1/PD-L1 axis as a potential therapeutic target for the treatment of young STS patients.

30 July 2012 in BMC Genomics
Verified
Journal Article
Open access
PDF file
HKHan Sang Kim
Han Sang Kim
SKSang Cheol Kim
Sang Cheol Kim
SKSun Jeong Kim
Sun Jeong Kim
CPChan Hee Park
Chan Hee Park
HJHei-Cheul Jeung
Hei-Cheul Jeung
SRSun Young Rha
Sun Young Rha
Background: In the postgenome era, a prediction of response to treatment could lead to better dose selection for patients in radiotherapy. To identify a radiosensitive gene signature and elucidate related signaling pathways, four different microarray experiments were reanalyzed before radiotherapy.Results: Radiosensitivity profiling data using clonogenic assay and gene expression profiling data from four published microarray platforms applied to NCI-60 cancer cell panel were used. The survival fraction at 2 Gy (SF2, range from 0 to 1) was calculated as a measure of radiosensitivity and a linear regression model was applied to identify genes or a gene set with a correlation between expression and radiosensitivity (SF2). Radiosensitivity signature genes were identified using significant analysis of microarrays (SAM) and gene set analysis was performed using a global test using linear regression model. Using the radiation-related signaling pathway and identified genes, a genetic network was generated. According to SAM, 31 genes were identified as common to all the microarray platforms and therefore a common radiosensitivity signature. In gene set analysis, functions in the cell cycle, DNA replication, and cell junction, including adherence and gap junctions were related to radiosensitivity. The integrin, VEGF, MAPK, p53, JAK-STAT and Wnt signaling pathways were overrepresented in radiosensitivity. Significant genes includingACTN1,CCND1,HCLS1,ITGB5,PFN2,PTPRC,RAB13, andWAS, which are adhesion-related molecules that were identified by both SAM and gene set analysis, and showed interaction in the genetic network with the integrin signaling pathway.Conclusions: Integration of four different microarray experiments and gene selection using gene set analysis discovered possible target genes and pathways relevant to radiosensitivity. Our results suggested that the identified genes are candidates for radiosensitivity biomarkers and that integrin signaling via adhesion molecules could be a target for radiosensitization.

18 November 2010 in Cancer
Verified
Journal Article
Open access
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JAJoong Bae Ahn
Joong Bae Ahn
WCWoon Bok Chung
Woon Bok Chung
OMOsamu Maeda
Osamu Maeda
SSSang Joon Shin
Sang Joon Shin
HKHyun Soo Kim
Hyun Soo Kim
JIJean-Pierre Issa
Jean-Pierre Issa
BACKGROUND: In colorectal cancer (CRC), DNA methylation anomalies define distinct subgroups termed CpG island methylator phenotype 1 (CIMP1), CIMP2, and CIMP‐negative. The role of this classification in predicting recurrence and disease‐free survival (DFS) in resected stage III CRC was evaluated.METHODS: Sporadic cancers from 161 patients were analyzed. Bisulfite pyrosequencing was used to examine the methylation of 2 global DNA methylation markers (LINE‐1, Alu) and 9 loci (MINT1, MINT2, MINT31, P16, hMLH1, P14, SFRP1, SFRP2, and WNT5A). Mutations in BRAF and KRAS were assayed.RESULTS: Gene hypermethylation clustered in discrete groups of patients, indicating the presence of CIMP. K‐means clustering analysis identified 3 discrete subgroups: CIMP1 (n = 22, 13.7%), associated with proximal location and BRAF mutations; CIMP2 (n = 40, 24.8%), associated with KRAS mutations; and CIMP‐negative (n = 99, 61.5%), associated with distal location. In proximal CRC, CIMP1 was correlated with a higher recurrence rate (53% for CIMP1, 18% for CIMP2, and 26% for CIMP‐negative) and a worse DFS (P = .015). Also in proximal CRC, LINE‐1 methylation was lower in patients whose cancer recurred compared with those whose cancer did not recur (P = .049). In multivariate analysis, CIMP1 and low LINE1 methylation were independent prognostic factors for DFS in proximal CRC (P = .008 for classification by K‐means clustering analysis; P = .040 for LINE‐1 methylation status).CONCLUSIONS: DNA methylation is a useful biomarker of recurrence in resected stage III proximal but not distal CRC. However, as the number of CIMP1 cases was small in distal CRC, further study is required to validate our findings. Cancer 2011. © 2010 American Cancer Society.