Sung Kim

Sungkyunkwan University, Sŏul, Seoul, South Korea

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Publications (111)407.56 Total impact

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    ABSTRACT: Despite the close link between cigarette smoking and the development of gastric cancer, little is known about the effects of cigarette smoking on surgical outcomes after gastric cancer surgery. The aim of this study was to investigate whether preoperative smoking status and the duration of smoking cessation were associated with short-term surgical consequences in gastric cancer surgery.
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    ABSTRACT: Growth factor receptors, often carrying tyrosine kinase activities in their cytoplasmic domains, are overexpressed in many cancers. Coactivation of receptor tyrosine kinases (RTKs) plays a critical role in tumor response to targeted therapeutics. We examined concomitant overexpression of EGFR and MET in patients with HER2+ and HER2- gastric cancers (GCs). Tissue microarray samples obtained from 1,589 GC patients who received R0 gastrectomy with extensive node dissection and adjuvant chemoradiationtherapy were analyzed by immunohistochemistry and fluorescence in situ hybridization. HER2+ was observed in 169 patients (11%). Out of 169 HER2+ patients, 15 (9%) were EGFR+ and MET+, 29 (17%) were EGFR+, 37 (22%) were MET+, and the remaining 88 patients (52%) were HER2+ only, without concomitant EGFR or MET overexpression. Greater number of overexpressed RTKs correlated with younger age (p<0.001), larger tumor size (p=0.027), intestinal histology (p<0.001), and shorter overall survival (p=0.002). The mean overall survival was 113 months for HER2-/EGFR-/MET- and 63 months for HER2+/EGFR+/MET+ subgroups. Patients with HER2+/EGFR+/MET+ GCs had a substantial risk of death with a hazard ratio of 3.01 (95% CI, 1.54–5.90), compared to HER2-/EGFR-/MET- GC patients. Using patient-derived tumor cell models isolated from pericardial effusion of HER2+ and MET+ GC cases, we demonstrated that the combination of HER2-inhibitor (lapatinib) and MET-inhibitor offered a more profound inhibition in the ERK/AKT pathway and cell proliferation than lapatinib alone. Co-overexpression of RTKs was demonstrated in small subsets of GC associated with aggressive behavior, and in these cases, combination therapy may be considered as potential treatment options. © 2014 Wiley Periodicals, Inc.
    International Journal of Cancer 08/2014; · 6.20 Impact Factor
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    ABSTRACT: Recently, three prospective randomized trials have shown that adjuvant radiotherapy (ART) after radical prostatectomy for the patients with pT3 and/or positive margins improves biochemical progression-free survival and local recurrence free survival. But, the optimal management of these patients after radical prostatectomy is an issue which has been debated continuously. The object of this study was to determine the necessity of adjuvant radiotherapy (ART) by reviewing the outcomes of observation without ART after radical prostatectomy (RP) in patients with pathologic indications for ART according to the American Urological Association (AUA)/American Society for Radiation Oncology (ASTRO) guideline. From a prospectively maintained database, 163 patients were eligible for inclusion in this study. These men had a pathological stage pT2-3 N0 with undetectable PSA level after RP and met one or more of the three following risk factors: capsular perforation, positive surgical margins, or seminal vesicle invasion. We excluded the patients who had received neoadjuvant hormonal therapy or adjuvant treatment, or had less than 24 months of follow-up. To determine the factors that influenced biochemical recurrence-free (BCR), univariate and multivariate Cox proportional hazards analyses were performed. Among the 163 patients, median follow-up was 50.5 months (24.0-88.2 months). Of those men under observation, 27 patients had BCR and received salvage radiotherapy (SRT). The multivariate Cox analysis showed that BCR was marginally associated with pre-operative serum PSA (P = 0.082), and the pathologic GS (HR, 4.063; P = 0.001) was an independent predictor of BCR. More importantly, in 87 patients with pre-operative PSA < 6.35 ng/ml and GS <= 7, only 3 developed BCR. Of the 163 patients who qualified for ART based on the current AUA/ASTRO guideline, only 27 (16.6%) developed BCR and received SRT. Therefore, using ART following RP using the current recommendation may be an overtreatment in an overwhelming majority of the patients.
    BMC Urology 04/2014; 14(1):30. · 1.69 Impact Factor
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    ABSTRACT: Although early detection and improved treatment have increased the number of long-term survivors, little is known about the prevalence and associations of clinically relevant fatigue (CRF) in disease-free stomach cancer survivors. Because no effective CRF management strategy yet exists, understanding CRF risk factors is important for developing treatment approaches. Stomach cancer survivors (N = 374) completed a mailed survey that included the Brief Fatigue Inventory, Beck Depression Inventory, and the European Organization for Research and Treatment of Cancer QLQ-C30 questionnaire and its gastric module QLQ-STO22. We assessed sociodemographic, clinical, and symptom characteristics using multivariate logistic regression models to identify CRF-associated factors. Approximately half of disease-free stomach cancer survivors reported CRF, which was associated with female gender, low economic status, rural residence, current smoker, early tumor progress, current depression, and poor performance. Significant relationships of CRF with current depression and poor performance status remained robust after adjusting for potential confounders. Most functional and symptom scores of fatigued survivors deteriorated more than in non-fatigued survivors. Additionally, congruence between tumor progress and surgery type might influence CRF severity. In disease-free stomach cancer survivors, CRF is a common problem that is strongly associated with quality of life and other symptoms. Current depression, poor performance, and perceived understanding regarding postoperative condition are important CRF risk factors. Thus, CRF management in this population should focus on identifying these factors.
    Supportive Care in Cancer 01/2014; · 2.09 Impact Factor
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    ABSTRACT: Despite the benefits from adjuvant chemotherapy or chemoradiotherapy, approximately one-third of stage II gastric cancer (GC) patients developed recurrences. The aim of this study was to develop and validate a prognostic algorithm for gastric cancer (GCPS) that can robustly identify high-risk group for recurrence among stage II patients. A multi-step gene expression profiling study was conducted. First, a microarray gene expression profiling of archived paraffin-embedded tumor blocks was used to identify candidate prognostic genes (N = 432). Second, a focused gene expression assay including prognostic genes was used to develop a robust clinical assay (GCPS) in stage II patients from the same cohort (N = 186). Third, a predefined cut off for the GCPS was validated using an independent stage II cohort (N = 216). The GCPS was validated in another set with stage II GC who underwent surgery without adjuvant treatment (N = 300). GCPS was developed by summing the product of Cox regression coefficients and normalized expression levels of 8 genes (LAMP5, CDC25B, CDK1, CLIP4, LTB4R2, MATN3, NOX4, TFDP1). A prospectively defined cut-point for GCPS classified 22.7% of validation cohort treated with chemoradiotherapy (N = 216) as high-risk group with 5-year recurrence rate of 58.6% compared to 85.4% in the low risk group (hazard ratio for recurrence = 3.16, p = 0.00004). GCPS also identified high-risk group among stage II patients treated with surgery only (hazard ratio = 1.77, p = 0.0053).
    PLoS ONE 01/2014; 9(3):e90133. · 3.73 Impact Factor
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    ABSTRACT: CD151, a transmembrane protein of the tetraspanin family, is implicated in the regulation of cell-substrate adhesion and cell migration. Overexpression of CD151 has been reported in several cancers and controls MET-dependent neoplastic growth by enhancing receptor signaling. However, association of CD151 overexpression with MET or tumor progression has not been reported in gastric cancer. We conducted immunohistochemical analysis of CD151 overexpression in 491 pT3 gastric carcinomas and analyzed the relationship with MET overexpression and prognostic significance. CD151 was highly expressed in 119 gastric carcinomas (24.2 %) and was significantly associated with higher pN stages. Patients with CD151-positive gastric cancer showed shorter overall (p = 0.003) and disease-free survival (p = 0.001) compared with patients with CD151-negative gastric carcinoma. CD151 overexpression was an independent prognostic factor for overall survival [hazard ration (HR) 1.335; 95 % CI 1.005-1.775; p = 0.046] and disease-free survival (HR 1.903; 95 % CI 1.348-2.685; p < 0.001). Co-overexpression of CD151 and MET was observed in 30 (6.1 %) gastric cancers and was more frequent in advanced pN stages than in other groups. Moreover, co-overexpression of CD151 and MET was a strong independent prognostic factor for overall survival (HR 3.163; 95 % CI 1.958-5.108; p < 0.001) and disease-free survival (HR 3.834; 95 % CI 2.145-6.852; p < 0.001). CD151 overexpression is an independent prognostic factor and could be a potential molecular therapeutic target in patients with advanced gastric cancers. Further studies are needed to establish the biological significance of CD151/MET co-overexpression and the potential of targeting both molecules as a therapeutic strategy.
    Annals of Surgical Oncology 12/2013; · 4.12 Impact Factor
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    ABSTRACT: Reoperations after gastrectomy for gastric cancer are performed for many types of complications. Unexpected reoperations may cause mental, physical, and financial problems for patients. The aim of the present study was to evaluate the causes of reoperations and to develop a strategic decision-making process for these reoperations. From September 2002 through August 2010, 6,131 patients underwent open conventional gastrectomy operations at Samsung Medical Center. Of these, 129 patients (2.1%) required reoperation because of postoperative complications. We performed a retrospective analysis of the patients using an electronic medical record review. Statistical data were analyzed to compare age, sex, stage, type of gastrectomy, length of operation, size of tumor, and number of lymph node metastasis between patients who had been operated and those who had not. The variables of age, sex, tumor stage, type of gastrectomy, length of operation, and number of lymph node metastases did not differ between the 2 groups. However, the mean tumor size in the reoperation group was greater than that in the non-reoperation group (5.0±3.7 [standard deviation] versus 4.1±2.9, P=0.007). The leading cause of reoperation was surgical-site infection (n=49, 0.79%). Patients with intra-abdominal bleeding were operated on again in the shortest period after the initial gastrectomy (6.3±4.2 days). Patients with incisional hernia were not reoperated on until after 208.3±81.0 days, the longest postoperative period. Tumor size was the major variable leading to reoperation after gastrectomy for gastric cancer. The most common complication requiring the reoperation was a surgical site-related complication.
    Journal of gastric cancer. 12/2013; 13(4):242-6.
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    ABSTRACT: Although the suicide rate of cancer survivors is higher than that of the general population, few studies have examined the potential risk factors. We assessed suicide ideation (SI) and investigated its correlates among survivors of stomach cancer, which is one of the most prevalent cancers in Korea. We surveyed 378 stage I-III stomach cancer survivors who had been disease free for at least 1 year. The survey contained demographic questions and quality of life assessments from the European Organization for Research and Treatment of Cancer QLQ-C30 and its stomach cancer-specific module, the McGill Quality of Life Questionnaire, the Brief Fatigue Inventory, and one question from the Beck Depression Inventory. We found that 131/378 stomach cancer survivors (34.7 %) experienced SI. Univariate analyses showed that SI was significantly associated with income, comorbidity, smoking, and the following quality of life factors: general health status, emotional functioning, fatigue, nausea/vomiting, dyspnea, appetite loss, constipation, diarrhea, financial problems, eating restriction, anxiety, dry mouth, trouble belching, hair loss, body image, existential well-being, and social support. Multivariate logistic regression confirmed that SI was independently associated with diarrhea (adjusted odds ratio (aOR) 2.84; 95 % confidence interval (CI) 1.44-5.62), hair loss (aOR 2.77; 95 % CI 1.04-7.36), existential well-being (aOR 6.18; 95 % CI 2.91-13.1), and usual fatigue (aOR 2.29; 95 % CI 1.30-4.06). Our findings reveal a high prevalence of SI among stomach cancer survivors and identify health-related quality of life issues such as diarrhea, hair loss, existential well-being, and fatigue as important risk factors of SI.
    Supportive Care in Cancer 09/2013; · 2.09 Impact Factor
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    ABSTRACT: Use of ultrasonically activated shears (UAS) is gaining popularity in open surgery but without concrete evidence. We conducted a prospectively randomized study to assess the efficacy of ultrasonic dissection in open gastrectomy for gastric cancer. Patients with gastric cancer who were to undergo gastrectomy with D2 lymph node dissection were enrolled and assigned to either the conventional surgery group (n = 125) or the UAS group (n = 128). The mean operating time was significantly reduced in the UAS group (89.3 ± 15.6 min) when compared to the conventional group (97.8 ± 17.2 min; p < 0.001). However, we did not find any significant difference in operative blood loss, the amount of postoperative abdominal drainage, or the rate of postoperative complications between the groups. A multivariate analysis for operating time revealed that the use of UAS, female gender and BMI less than 25 were significantly associated with reduced operating time. The operating time was significantly longer in the conventional group than in the UAS group (B 7.786; 95 % CI 4.103-11.468; p < 0.001). In the subgroup analysis, the use of UAS significantly reduced the operating time, especially in male patients, regardless of the BMI status. The use of UAS in gastrectomy for gastric cancer was a safe and efficient method, especially in terms of reducing operating time for male patients.
    Gastric Cancer 09/2013; · 3.99 Impact Factor
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    ABSTRACT: Although terminal cancer is a widely used term, its meaning varies, which may lead to different attitudes toward end-of-life issues. The study was conducted to investigate differences in the understanding of terminal cancer and determine the relationship between this understanding and attitudes toward end-of-life issues. A questionnaire survey was performed between 2008 and 2009. A total of 1242 cancer patients, 1289 family caregivers, 303 oncologists from 17 hospitals, and 1006 participants from the general population responded. A "6-month life expectancy" was the most common understanding of terminal cancer (45.6%), followed by "treatment refractoriness" (21.1%), "metastatic/recurrent disease" (19.4%), "survival of a few days/weeks" (11.4%), and "locally advanced disease" (2.5%). The combined proportion of "treatment refractoriness" and "6-month life expectancy" differed significantly between oncologists and the other groups combined (76.0% v. 65.9%, P = 0.0003). Multivariate analyses showed that patients and caregivers who understood terminal cancer as "survival of a few days/weeks" showed more negative attitudes toward disclosure of terminal status compared with participants who chose "treatment refractoriness" (adjusted odds ratio [aOR] 0.42, 95% confidence interval [CI] 0.22-0.79 for patients; aOR 0.34, 95% CI 0.18-0.63 for caregivers). Caregivers who understood terminal cancer as "locally advanced" or "metastatic/recurrent disease" showed a significantly lower percentage of agreement with withdrawal of futile life-sustaining treatment compared with those who chose "treatment refractoriness" (aOR 0.19, 95% CI 0.07-0.54 for locally advanced; aOR 0.39, 95% CI 0.21-0.72 for metastatic/recurrent). The understanding of terminal cancer varied among the 4 participant groups. It was associated with different preferences regarding end-of-life issues. Standardization of these terms is needed to better understand end-of-life care.
    Medical Decision Making 08/2013; · 2.89 Impact Factor
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    ABSTRACT: The establishment of better selection criteria for identifying sub-populations that may benefit from treatment is a key aspect of the development and success of targeted therapy. To investigate methods for assessing MET overexpression in gastric cancer, we conducted immunohistochemistry using a new anti-Total MET monoclonal antibody in a single-institution cohort of 495 patients. As antibody is directed against a membranous and/or cytoplasmic epitope, two interpretation methods were used: (1) membranous and cytoplasmic and (2) membranous alone. In selected 120 cases, copy number gain and mRNA expression levels were measured using quantitative real-time PCR. Further in situ hybridization confirmed the presence of MET gene amplification. Among the 495 gastric cancers, simultaneous membranous and cytoplasmic overexpression of MET was found in 108 cases (21.8%) and membranous alone overexpression was observed in 40 cases (8.1%). The highest correlation was observed in membranous and cytoplasmic staining of MET: MET expression scores correlated significantly with high MET mRNA levels (r=0.465, P<0.0001), increased copy number gain (r=0.393, P=0.000002) and amplification of MET gene. Moreover, patients with MET overexpression showed shorter overall survival (HR, 1.781; 95% CI, 1.324-2.395; P<0.001) and disease-free survival (HR, 1.765; 95% CI, 1.227-2.541; P=0.002) compared with patients without MET overexpression. However, membranous overexpression of MET did not highly correlate with mRNA level (r=0.274, P=0.002), copy number gain or survival (P>0.05). We developed highly correlating interpretation methods of MET immunohistochemistry in gastric carcinomas. MET overexpression is an independent prognostic factor and could be a potential target and predictor of benefit for targeted therapy with MET inhibitors.Modern Pathology advance online publication, 28 June 2013; doi:10.1038/modpathol.2013.108.
    Modern Pathology 06/2013; · 5.25 Impact Factor
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    ABSTRACT: BACKGROUND: Data regarding the difference in the clinical course from metastasis to prostate cancer-specific mortality (PCSM) following radical prostatectomy (RP) compared with radiation therapy (RT) are lacking. OBJECTIVE: To examine the association between primary treatment modality and prostate cancer-specific survival (PCSS) after metastasis. DESIGN, SETTING, AND PARTICIPANTS: We used the Surveillance Epidemiology and End Results-Medicare linked database from 1994 to 2007 for patients diagnosed with localized prostate cancer (PCa). We used cancer stage and Gleason score to stratify patients into low and intermediate-high risks. INTERVENTION: Radical prostatectomy or radiation therapy. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Our outcome is time from onset of metastases to PCSM. Propensity score matching and Cox regression were used to analyze the PCSM hazard for the RP group compared with the RT group. RESULTS AND LIMITATIONS: Our study consisted of 66 492 men diagnosed with PCa, 51 337 men receiving RT, and 15 155 men undergoing RP within 1 yr of cancer diagnosis. During the study period, 2802 men were diagnosed as having metastatic disease. A total of 916 men with metastases were included in the propensity-matched cohort; of these men, 186 died from PCa. During the follow-up, for the low-risk patients, the adjusted PCSS after metastasis was 86.2% and 79.3% in the RP and RT groups, respectively; for the intermediate-high-risk patients, the PCSS after metastasis was 76.3% and 63.3% in the RP and RT groups, respectively. The hazard ratios estimating the risk of PCSM between the RP and RT groups were 0.64 (95% confidence interval [CI], 0.36-1.16) and 0.55 (95% CI, 0.39-0.77) for the low- and intermediate-high-risk groups, respectively. Because of the nature of observational studies, the results may be affected by residual confounders and treatment indication. CONCLUSIONS: Following the development of metastases, men who received primary RP have a longer PCSS than men who received primary RT. Our results may have implications for the timing and nature of local PCa treatment.
    European Urology 05/2013; · 10.48 Impact Factor
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    ABSTRACT: BACKGROUND: Current rates of survival for gastric cancer patients are much improved compared with those of the past. The purpose of our study was to analyze the survival of gastric cancer patients according to time period and to examine how different prognostic factors are related to changing survival rates. METHODS: We analyzed data from 7,757 patients who underwent curative gastrectomy after diagnoses of gastric cancer at Samsung Medical Center from 1994 to 2006. Clinicopathologic characteristics and prognostic factors were analyzed retrospectively, with patients divided into period I, from 1994 to 2001, and period II, from 2002 to 2006. RESULTS: The 5-year, disease-free survival rate of patients with gastric cancer increased significantly from 76.7 % during period I to 85.9 % during period II (p < 0.001). The prognosis of the patient who underwent surgery during period I was worse than that of the patient in period II. When multivariate analyses were performed for each time period, independent prognostic factors for period I included patient age >60 years, tumor located in the whole stomach, tumor size, stage, vascular invasion, perineural invasion, and adjuvant chemotherapy. For period II, tumor size, vascular, and adjuvant chemotherapy were no longer independent prognostic risk factors. CONCLUSIONS: The disease-free survival of gastric cancer improved and prognostic factors changed over time. Active, concurrent chemoradiotherapy together with radical gastric resection performed by an expert surgeon seemed to contribute to the improvement in the survival rates of gastric cancer.
    Annals of Surgical Oncology 05/2013; · 4.12 Impact Factor
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    ABSTRACT: CONTEXT: Depression in cancer survivors affects the rest of their lives in many ways. OBJECTIVES: To estimate the prevalence of depression and identify associated factors in disease-free stomach cancer survivors. METHODS: We enrolled 391 stomach cancer survivors who had been disease-free for at least one year after surgery from the cancer registries of two hospitals in Korea. Stomach cancer survivors were mailed a survey that included the Beck Depression Inventory, the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30, and the associated stomach module, the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-stomach cancer module 22 questionnaire. RESULTS: Forty-four percent of survivors suffered from depression, and more women (49%) than men (42%) had high depression scores (Beck Depression Inventory >13). In multiple logistic regression analysis, lower income (odds ratio [OR] 2.49; 95% CI 1.64-3.78), problems with care before treatment (OR 1.92; 95% CI 1.23-2.98), body image change (OR 2.23; 95% CI 1.41-3.53), and symptoms of fatigue (OR 3.11; 95% CI 1.49-6.52), dyspnea (OR 2.57; 95% CI 1.48-4.45), or insomnia (OR 4.51; 95% CI 1.88-10.83) were associated with depression. CONCLUSION: The prevalence of depression was high in stomach cancer survivors even after the completion of treatment, especially among those with problems amenable to treatment, and we identified the associated factors. We suggest that the stomach cancer survivors should be screened for depression after the end of treatment.
    Journal of pain and symptom management 03/2013; · 2.42 Impact Factor
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    ABSTRACT: Gastric cancer (GC) is the most common malignancy. The incidence rates remain remarkably high in East Asians. Although genome-wide association studies in the Han Chinese and Japanese populations have so far yielded susceptibility loci for GC, these findings need to be validated in an independent ethnic group. To identify the potential heterogeneity by histological classified subtypes (intestinal and diffuse), we examined the previously reported associations in the Korean population. PRKAA1 at 5p13.1 was found to be more strongly associated with intestinal type (odds ratio, OR=1.39, 95% CI (confidence interval) =1.22-1.58, P=3.77 × 10(-7)) than diffuse type. In addition, PSCA at 8q23.3 was significantly replicated in diffuse type (OR=1.49, 95% CI=1.32-1.67, P=2.43 × 10(-11)) but far less significant in intestinal type. In conclusion, these findings could bring additional insights into the etiologic heterogeneity in gastric carcinogenesis mechanisms.Journal of Human Genetics advance online publication, 7 February 2013; doi:10.1038/jhg.2012.158.
    Journal of Human Genetics 02/2013; · 2.37 Impact Factor
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    ABSTRACT: To explore the target protein expression in separate tumors in a patient with synchronous multiple gastric carcinomas (SMGCs). Immunohistochemistry for HER2, EGFR, and MET were performed in 282 carcinomas from 141 patients. Of 141 patients with SMGCs, 11.3%, 23.4%, and 14.9% of cases showed HER2, EGFR, and MET protein overexpression, respectively. In SMGC cases with overexpression of target proteins in > 1 tumor, intertumoral heterogeneity was 81.3% (13/16) for HER2, 78.8% (26/33) for EGFR, and 90.5% (19/21) for MET protein. The concordance rate of HER2, EGFR, and MET expression between 2 carcinomas from the same patient was 90.8%, 81.6%, and 86.5%, respectively, with a kappa value below 0.3, indicating slight to fair agreement. We found a considerable intertumoral heterogeneity of target protein overexpression in SMGCs. Our findings support a multicentric origin for SMGC and emphasize the need to perform immunohistochemistry for all synchronous lesions.
    Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology 02/2013; 35(1):27-35. · 0.60 Impact Factor
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    ABSTRACT: Gastric carcinoma is one of the major causes of cancer-related mortality worldwide. Early detection and treatment leads to an excellent prognosis in patients with early gastric cancer (EGC), whereas the prognosis of patients with advanced gastric cancer (AGC) remains poor. It is unclear whether EGCs and AGCs are distinct entities or whether EGCs are the beginning stages of AGCs. We performed whole exome sequencing of four samples from patients with EGC and compared the results with those from AGCs. In both EGCs and AGCs, a total of 268 genes were commonly mutated and independent mutations were additionally found in EGCs (516 genes) and AGCs (3104 genes). A higher frequency of C>G transitions was observed in intestinal-type compared to diffuse-type carcinomas (P = 0.010). The DYRK3, GPR116, MCM10, PCDH17, PCDHB1, RDH5 and UNC5C genes are recurrently mutated in EGCs and may be involved in early carcinogenesis.
    PLoS ONE 01/2013; 8(12):e82770. · 3.73 Impact Factor
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    ABSTRACT: Background: To determine whether the Health Partner Program is effective in training long-term cancer survivors to be health coaches. Materials and Methods: We randomly assigned cancer survivors who were selected through a rigorous screening process to either the Health Partner Program or the waiting-list control group. The program consisted of 8 weeks of training in health management, leadership, and coaching. At baseline, 8, and 16 weeks, we measured primary outcomes using the Seven Habit Profile (SHP), the Korean Leadership Coaching Competency Inventory (KCCI), Ed Diner's Satisfaction with Life Scale (SWLS), and the Posttraumatic Growth inventory (PTGI) and secondary outcomes using the Hospital Anxiety and Depression Scale (HADS), the Impact of Event Scale-Revised (IES-R), and the Medical Outcomes Study (MOS) short form 36-item questionnaire (SF- 36). Results: We recruited 70 subjects and randomly assigned 34 to the intervention group. The Sharpen the Saw habit of the SHP increased significantly more in intervention group than in the control group (p = 0.049), as did most PTGI factors. The intervention group also showed a significantly greater enhancement of vitality (p = 0.015) and mental health (p = 0.049) SF-36 scores but no improvement in KCCI, SWLS, HADS, or IES-R scores. The intervention group also showed a greater clinically meaningful improvement in the "Think Win-Win" of SHP (p = 0.043) and in the personal strength score (p = 0.025) and total score (p = 0.015) of the PTGI. Conclusions: Long-term cancer survivors can benefit from the Health Partner Program to become health coaches.
    Asian Pacific journal of cancer prevention: APJCP 01/2013; 14(12):7229-35. · 1.27 Impact Factor
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    ABSTRACT: Oncogenic mutations in gastrointestinal stromal tumors (GISTs) predict prognosis and therapeutic responses to imatinib. In wild-type GISTs, the tumor-initiating events are still unknown, and wild-type GISTs are resistant to imatinib therapy. We performed an association study between copy number alterations (CNAs) identified from array CGH and gene expression analyses results for four wild-type GISTs and an imatinib-resistant PDGFRA D842V mutant GIST, and compared the results to those obtained from 27 GISTs with KIT mutations. All wild-type GISTs had multiple CNAs, and CNAs in 1p and 22q that harbor the SDHB and GSTT1 genes, respectively, correlated well with expression levels of these genes. mRNA expression levels of all SDH gene subunits were significantly lower (P≤0.041), whereas mRNA expression levels of VEGF (P=0.025), IGF1R (P=0.026), and ZNFs (P<0.05) were significantly higher in GISTs with wild-type/PDGFRA D842V mutations than GISTs with KIT mutations. qRT-PCR validation of the GSTT1 results in this cohort and 11 additional malignant GISTs showed a significant increase in the frequency of GSTT1 CN gain and increased mRNA expression of GSTT1 in wild-type/PDGFRA D842V GISTs than KIT-mutant GISTs (P=0.033). Surprisingly, all four malignant GISTs with KIT exon 11 deletion mutations with primary resistance to imatinib had an increased GSTT1 CN and mRNA expression level of GSTT1. Increased mRNA expression of GSTT1 and ZNF could be predictors of a poor response to imatinib. Our integrative approach reveals that for patients with wild-type (or imatinib-resistant) GISTs, attempts to target VEGFRs and IGF1R may be reasonable options.
    PLoS ONE 01/2013; 8(10):e77219. · 3.73 Impact Factor
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    ABSTRACT: PURPOSE: The aim of this study was to utilize the proteomics-based Collaborative Enzyme Enhanced Reactive (CEER) immunoassay to investigate protein tyrosine phosphorylations as diagnostic markers in gastric cancers (GCs). EXPERIMENTAL DESIGN: Protein lysates from fresh-frozen 434 advanced stage GCs were analyzed for phosphorylation of HER1, HER2, p95HER2, HER3, cMET, IGF1R and PI3K. The pathway activation patterns were segregated based on the tumor HER2 status. Hierarchical clustering was utilized to determine pathway coactivations in GCs. Prognostic value of pathway activation patterns was determined by correlating disease-free survival times of the various GC subgroups using Kaplan-Meier survival analysis. CEER was also used to determine the presence of tyrosine phosphorylated signaling cascades in circulating tumor cells (CTCs) and ascites tumor cells (ATCs). RESULTS: Utilizing a novel diagnostics immunoassay, CEER, we demonstrate the presence of p95HER2 and concomitantly activated signaling pathways in GC tumor tissues, CTCs and ATCs isolated from GC patients for the first time. p95HER2 is expressed in ∼77% of HER2(+) GCs. Approximately 54% of GCs have an activated HER1, HER2, HER3, cMET or IGF1R and demonstrate a poorer prognosis than those where these receptor tyrosine kinases (RTKs) are not activated. Hierarchical clustering of RTKs reveals co-clustering of phosphorylated HER1:cMET, HER2:HER3 and IGF1R-PI3K. Coactivation of HER1 with cMET renders GCs with a shorter disease-free survival as compared to only cMET activated GCs. CONCLUSIONS: Our study highlights the utility of a novel companion diagnostics technology, CEER that has strong implications for drug development and therapeutic monitoring. CEER is used to provide an increased understanding of activated signaling pathways in advanced GCs that can significantly improve their clinical management through accurate patient selection for targeted therapeutics.
    PLoS ONE 01/2013; 8(1):e54644. · 3.73 Impact Factor

Publication Stats

837 Citations
407.56 Total Impact Points


  • 2006–2014
    • Sungkyunkwan University
      • • Department of Surgery
      • • Department of Pathology
      • • School of Medicine
      Sŏul, Seoul, South Korea
  • 2013
    • Samsung Medical Center
      • Department of Hematology and Oncology
      Seoul, Seoul, South Korea
    • Taipei Medical University
      • Graduate Institute of Clinical Medicine
      Taipei, Taipei, Taiwan
    • Chungbuk National University
      Chinsen, North Chungcheong, South Korea
    • Seoul National University
      • Department of Biomedical Sciences
      Seoul, Seoul, South Korea
  • 2012–2013
    • Seoul National University Hospital
      Sŏul, Seoul, South Korea
    • Dongguk University
      Sŏul, Seoul, South Korea
    • Ulsan University Hospital
      Urusan, Ulsan, South Korea
  • 2011–2013
    • Cancer Institute of New Jersey (CINJ)
      New York City, New York, United States
  • 2004–2013
    • National Cancer Center Korea
      • Gastric Cancer Branch
      Kōyō, Gyeonggi Province, South Korea
  • 2011–2012
    • Robert Wood Johnson University Hospital
      New Brunswick, New Jersey, United States
  • 2008–2010
    • Hanyang University
      • College of Medicine
      Ansan, Gyeonggi, South Korea
  • 2009
    • Seoul Veterans Hospital
      Sŏul, Seoul, South Korea
    • Yonsei University Hospital
      • Surgery
      Seoul, Seoul, South Korea
    • National and Kapodistrian University of Athens
      • Division of Surgery V
      Athens, Attiki, Greece
    • Daegu Haany University
      Daikyū, Daegu, South Korea
    • Yonsei University
      • Department of Surgery
      Seoul, Seoul, South Korea