Do-Youn Oh

Seoul National University, Sŏul, Seoul, South Korea

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Publications (182)504.53 Total impact

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    ABSTRACT: The aim of this study was to examine the efficacy and safety of everolimus in patients with progressive unresectable adenoid cystic carcinoma (ACC).
    BMC Cancer 11/2014; 14(1):795. · 3.33 Impact Factor
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    ABSTRACT: To evaluate the prognostic significance of phosphorylated Akt (p-Akt), phosphorylated mammalian target of rapamycin (p-mTOR), and total phosphatase and tensin homolog deleted on chromosome 10 (PTEN) expressions in patients undergoing adjuvant chemoradiotherapy (CRT) for proximal extrahepatic bile duct (EHBD) cancer.
    American Journal of Clinical Oncology 08/2014; · 2.55 Impact Factor
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    ABSTRACT: The purpose of this study was to evaluate treatment patterns, outcome and prognosticators for patients with leptomeningeal metastases from solid tumor. Medical records of 80 patients from January 1, 2004 to May 31, 2011 were retrospectively reviewed. Most frequent site of origin was the lung (59%) followed by the breast (25%). Most patients were treated with intrathecal chemotherapy (90%) and/or whole brain radiotherapy (67.5%). Systemic therapy was offered to 27 patients (33.8%). Percentage of patients treated with single, dual, and triple modality were 32.5%, 43.8%, and 23.8%, respectively. Median survival was 2.7 months and 1 yr survival rate was 11.3%. Multivariate analysis showed that negative cerebrospinal fluid cytology, fewer chemotherapy regimen prior to leptomeningeal metastases, whole brain radiotherapy, systemic therapy, and combined modality treatment (median survival; single 1.4 vs. dual 2.8 vs. triple 8.3 months, P<0.001) had statistical significance on survival. Subgroup analysis of non-small cell lung cancer (NSCLC) patients showed that targeted therapy had significant independent impact on survival (median survival; 10.5 vs. 3.0 months, P=0.008). Unlike previous reports, survival of patients with NSCLC primary was comparable to breast primary. Furthermore, combined modality treatment for all patients and additionally targeted therapy for NSCLC patients should be considered in the treatment of leptomeningeal metastases from solid tumor.
    Journal of Korean medical science. 08/2014; 29(8):1094-101.
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    ABSTRACT: Aim: To identify immunohistochemical (IHC) features associated with sensitivity to lapatinib-plus-capecitabine (LX) and resistance to trastuzumab in human epidermal growth factor receptor (HER)-2-positive metastatic breast cancer. Patients and Methods: Expression levels of estrogen receptor, progesterone receptor, epidermal growth factor receptor, HER2, HER3/phosphorylated HER3 (pHER3), phosphatase and tensin homolog, thymidylate synthase (TYMS), and thymidine phosphorylase by IHC were compared between patients treated with LX following trastuzumab failure. Results: In 35 patients, HER2 was the only biomarker associated with LX treatment outcomes. A high HER2 level was associated with significantly longer survival and a tendency towards longer time-to-progression and higher response rates. Acquisition of trastuzumab resistance was associated with higher pHER3 and TYMS expression. Elevated pHER3 was predictive of superior treatment outcomes. Conclusion: Up-regulation of pHER3 and TYMS was associated with trastuzumab resistance. High HER2 and increased pHER3 IHC levels correlated with favourable LX treatment outcomes in patients with HER2-positive metastatic breast cancer.
    Anticancer research 08/2014; 34(8):4275-4280. · 1.71 Impact Factor
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    ABSTRACT: The purpose of this study is to determine the maximum tolerated dose (MTD), safety, pharmacokinetics, and recommended phase II dose of an oral drug composed of paclitaxel and HM30181A, which is an inhibitor of P-glycoprotein, in patients with advanced cancers.
    Cancer research and treatment : official journal of Korean Cancer Association. 07/2014; 46(3):234-242.
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    ABSTRACT: A newly isolated mediastinal lymph node (LN) or a small pulmonary nodule, which appears during breast cancer surveillance, may pose a diagnostic dilemma with regard to malignancy. We conducted this study to determine which clinical factors were useful for the differentiation of malignant lesions from benign lesions under these circumstances.
    Cancer research and treatment : official journal of Korean Cancer Association. 07/2014; 46(3):280-287.
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    ABSTRACT: To investigate the efficacy of gemcitabine plus uracil-tegafur (UFT) combination chemotherapy as a salvage treatment in patients with metastatic colorectal cancer (MCRC).
    Cancer Chemotherapy and Pharmacology 06/2014; · 2.80 Impact Factor
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    ABSTRACT: Although KRAS mutation has a predictive role in stage IV colorectal cancer (CRC) patients treated with anti-EGFR therapy, there have been controversies in the prognostic impact of KRAS mutation in stage II or III disease. The purpose of this study was to assess the prognostic impact of KRAS and BRAF mutation in patients treated with adjuvant 5-fluorouracil/leucovorin/oxaliplatin (FOLFOX).
    Annals of Surgical Oncology 06/2014; · 4.12 Impact Factor
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    ABSTRACT: To analyze the outcome of patients with ampullary cancer who had undergone curative surgery followed by adjuvant chemoradiotherapy and to identify the prognostic factors for these patients METHODS:: Between January 1991 and August 2006, 71 patients with ampullary cancer underwent curative resection followed by adjuvant radiotherapy. There were 38 males and 33 females, and median age was 56 years (range, 28 to 77 y). Postoperative radiotherapy was delivered to tumor bed and regional lymph nodes up to 40 to 50 Gy at 2 Gy/fraction; 67 patients also received intravenous 5-fluorouracil as a radiosensitizer. Median follow-up duration was 72 months for survivors. There were 5 isolated locoregional recurrences, 20 isolated distant metastases, and 11 combined locoregional and distant relapses. The 5-year locoregional relapse-free and overall survival rates were 76.2% and 64.5%, respectively. On multivariate analysis, nodal ratio and histologic differentiation were significant prognostic factors for overall survival (P=0.0382 and 0.0331, respectively). Adjuvant chemoradiotherapy after curative resection can achieve a long-term survival rate in patients with ampullary cancer. Nodal ratio and histologic differentiation are independent prognostic factors for these patients.
    American journal of clinical oncology 04/2014; · 2.21 Impact Factor
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    ABSTRACT: High body mass index (BMI) is linked to an increased risk of developing pancreatic cancer (PC). However, in patients with advanced PC (APC), especially those receiving palliative chemotherapy, the impact of BMI on survival has not been investigated fully. To assess changes in BMI during the course of APC and their impact on patient survival, specifically for those receiving palliative chemotherapy. Consecutive patients with APC, all of whom were treated with palliative chemotherapy, were enrolled during 2003-2010. Clinical characteristics and prognoses were analyzed. A total of 425 patients participated (median age, 60.1 years). At diagnosis of APC, patients' BMI distribution of patients was as follow: <18.5 (45, 10.6%); 18.5-19.9 (67, 15.8%); 20.0-22.4 (156, 36.7%); 22.5-24.9 (107, 25.2%); 25.0-29.9 (49, 11.5%); and ≥30.0 (1, 0.2%). Median overall survival (OS) was 8.1 months (95% confidence interval 7.2, 9.1). Precancer BMI and baseline BMI (at diagnosis) had no impact on OS. Weight loss at diagnosis (precancer weight minus weight at diagnosis) and weight loss during first-line chemotherapy (both stipulated as BMI change ≥1) were associated with shortened OS (hazard ratio, 1.300; P = 0.012 and hazard ratio, 1.367; P = 0.010, respectively). In patients with APC undergoing palliative chemotherapy, decreases in BMI at APC diagnosis and during chemotherapy are more hazardous for OS than precancer BMI or baseline BMI (at diagnosis) as absolute values. Further studies are needed to validate this finding and investigate strategies to maintain BMI during chemotherapy in this setting.
    Journal of pain and symptom management 12/2013; · 2.42 Impact Factor
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    ABSTRACT: Circumferential resection margin (CRM) and distal resection margin (DRM) have different impact on clinical outcomes after preoperative chemoradiotherapy (CRT) followed by surgery. Effect and adequate length of resection margin as well as impact of treatment response after preoperative CRT was evaluated. Total of 403 patients with rectal cancer underwent preoperative CRT followed by total mesorectal excision between January 2004 and December 2010. After applying the criterion of margin less than 0.5 cm for CRM or less than 1 cm for DRM, 151 cases with locally advanced rectal cancer were included as a study cohort. All patients underwent conventionally fractionated radiation with radiation dose over 50 Gy and concurrent chemotherapy with 5-fluorouracil or capecitabine. Postoperative chemotherapy was administered to 142 patients (94.0%). Median follow-up duration was 43.1 months. The 5-year overall survival (OS), disease-free survival (DFS), distant metastasis-free survival (DMFS) rates, and locoregional control rates (LRC) were 84.5%, 72.8%, 74.2%, and 86.3%, respectively. CRM of 1.5 mm and DRM of 7 mm were cutting points showing maximal difference in a maximally selected rank method. In univariate analysis, CRM of 1.5 mm was significantly related with worse clinical outcomes, whereas DRM of 7 mm was not. In multivariate analysis, CRM of 1.5 mm, and ypN were prognosticators for all studied endpoints. However, CRM was not a significant prognostic factor for good responders, defined as patients with near total regression or T down-staging, which was found in 16.5% and 40.5% among studied patients, respectively. In contrast, poor responders demonstrated a significant difference according to the CRM status for all studied end-points. Close CRM, defined as 1.5 mm, was a significant prognosticator, but the impact was only prominent for poor responders in subgroup analysis. Postoperative treatment strategy may be individualized based on this finding. However, findings from this study need to be validated with larger cohort.
    BMC Cancer 12/2013; 13(1):576. · 3.33 Impact Factor
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    ABSTRACT: Vascular endothelial growth factor (VEGF)-A, VEGF165b, interleukin (IL)-1β, and transforming growth factor (TGF)-β1 are known to influence tumor angiogenesis. Clinical implications of these cytokines need to be elucidated. Using clinical data and baseline serum samples of 140 consecutive patients with advanced non-small cell lung cancer who received platinum-based combination chemotherapy, we investigated the association among serum cytokine levels, treatment outcomes, as well as leukocyte and platelet counts. The median age of patients was 64 years (range, 26 to 86 years). The male to female ratio was 104:36. High TGF-β1 and IL-1β levels were associated with shorter progression-free survival, and high VEGF-A and IL-1β levels were associated with shorter overall survival in the univariate analysis. VEGF165b was not related to the treatment outcomes. Leukocytosis and thrombocytosis were associated with shorter overall survival. The multivariate analysis demonstrated that VEGF-A, IL-1β, and leukocytosis were significant prognostic factors (p=0.0497, p=0.047, and p<0.001, respectively). Leukocytosis was not associated with recent pneumonia (p=0.937) and correlated with VEGF-A (p<0.001) and TGF-β1 (p=0.020) levels. Serum VEGF-A, TGF-1β, and IL-1β levels, in addition to leukocyte and platelet counts, are shown to be associated with clinical outcomes. Leukocyte and platelet counts are correlated with serum VEGF-A and TGF-β1 levels.
    Cancer Research and Treatment 12/2013; 45(4):325-33. · 1.96 Impact Factor
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    ABSTRACT: To develop nomograms for predicting the overall survival (OS) and relapse-free survival (RFS) in patients with extrahepatic bile duct cancer undergoing adjuvant chemoradiation therapy after curative resection. From January 1995 through August 2006, a total of 166 consecutive patients underwent curative resection followed by adjuvant chemoradiation therapy. Multivariate analysis using Cox proportional hazards regression was performed, and this Cox model was used as the basis for the nomograms of OS and RFS. We calculated concordance indices of the constructed nomograms and American Joint Committee on Cancer (AJCC) staging system. The OS rate at 2 years and 5 years was 60.8% and 42.5%, respectively, and the RFS rate at 2 years and 5 years was 52.5% and 38.2%, respectively. The model containing age, sex, tumor location, histologic differentiation, perineural invasion, and lymph node involvement was selected for nomograms. The bootstrap-corrected concordance index of the nomogram for OS and RFS was 0.63 and 0.62, respectively, and that of AJCC staging for OS and RFS was 0.50 and 0.52, respectively. We developed nomograms that predicted survival and recurrence better than AJCC staging. With caution, clinicians may use these nomograms as an adjunct to or substitute for AJCC staging for predicting an individual's prognosis and offering tailored adjuvant therapy.
    International journal of radiation oncology, biology, physics 11/2013; 87(3):499-504. · 4.59 Impact Factor
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    ABSTRACT: Epidermal growth factor (EGF) is a ligand for the epidermal growth factor receptor (EGFR). Human epidermal growth factor receptor 2 (HER2) shares common signal pathways and forms a heterodimer with EGFR. In this study, we investigated the clinical and pathologic implications of serum EGF levels in patients with HER2-positive metastatic breast cancer (MBC). We analyzed serum EGF levels from baseline serum samples of consecutive patients with HER2-positive MBC who received first-line trastuzumab plus taxane chemotherapy and correlated them with treatment outcomes and pathologic features. A total of 50 women were analyzed. The median age was 47 years (range 27-72 years). Patients with high serum EGF levels (≥10.0 pg/mL) had significantly longer overall survival (47.0 months (95 % confidence interval (CI) 28.3-65.7 months) vs. 23.3 months (95 % CI 13.5-33.1 months); p = 0.009) with a tendency toward longer progression-free survival (p = 0.123). Serum EGF levels were not associated with hematologic or cardiac adverse events. Progesterone receptor-positive patients had significantly higher serum EGF levels than progesterone receptor-negative patients (24.3 pg/mL (range 9.5-69.0 pg/mL) vs. 12.3 pg/mL (range 0.0-59.5 pg/mL); p = 0.006). Our data suggest that high serum EGF levels may be associated with good prognosis in patients with HER2-positive MBC receiving trastuzumab plus taxane chemotherapy. In addition, serum EGF levels were associated with progesterone receptor positivity.
    Cancer Chemotherapy and Pharmacology 09/2013; · 2.80 Impact Factor
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    ABSTRACT: PURPOSE: This study aimed to elucidate the clinical implication of human epidermal growth factor receptor 2/centromeric probe for chromosome 17 (HER2/CEP17) ratio and HER2 immunohistochemistry (IHC) results in patients with HER2 fluorescence in situ hybridization (FISH)-positive metastatic breast cancer (MBC) who received first-line trastuzumab plus taxane chemotherapy. METHODS: Using clinical data of patients with HER2 FISH-positive MBC who received first-line trastuzumab plus taxane chemotherapy, we analyzed the clinical outcome according to the HER2/CEP17 ratio and HER2 IHC analysis. RESULTS: Fifty-two women were analyzed. The median age was 50 years (range 27-69 years). Patients with a HER2/CEP17 ratio ≥3.0 had significantly longer progression-free survival (PFS) (17.2 vs. 7.4 months; p = 0.002) with a tendency toward higher response rate (RR) (p = 0.325) and longer overall survival (OS) (p = 0.129). Patients with HER2 IHC 1+ had significantly shorter OS (14.0 vs. 42.4 months; p = 0.013) along with a tendency toward lower RR (p = 0.068) and shorter PFS (p = 0.220). In the multivariate analysis, HER2/CEP17 ratio <3.0 (p = 0.004) and Eastern Cooperative Oncology Group (ECOG) PS 2 (p = 0.015) were significant factors for shorter PFS, and HER2 IHC 1+ (p = 0.015) and ECOG PS 2 (p = 0.036) were significant factors for poor OS. CONCLUSIONS: Our data support that HER2/CEP17 ratios and HER2 IHC scores may predict clinical outcome after first-line trastuzumab plus taxane chemotherapy in patients with HER2 FISH-positive MBC.
    Cancer Chemotherapy and Pharmacology 05/2013; · 2.80 Impact Factor
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    ABSTRACT: The prognostic significance of ataxia-telangiectasia mutated (ATM) expression in gastric cancer remains unclear. The functional loss of the ATM gene exhibits a biologic correlation with microsatellite instability (MSI). In this study, we investigated the significance of ATM expression with MSI by evaluating gastric cancer patients who had undergone curative resection. ATM expression was classified into low ATM expression (-,+/-,+) and high ATM expression (++,+++) using immunohistochemistry analysis. MSI status was classified as MSI-negative (MSS, MSI-Low) and MSI-positive (MSI-High). Of 321 patients, 205 (63.9%) exhibited low ATM expression and 116 (36.1%) exhibited high ATM expression. Low ATM expression was more frequently identified in patients of older age, more advanced stage, and with MSI-positive tumor (p=0.025, p=0.001, and p=0.014, respectively). The probability of 5-year disease-free survival (DFS) and overall survival (OS) was lower in low ATM expression group compared to the high ATM expression group (DFS: 62.5%, 76.4%, p=0.017, OS: 65.9%, 78.5%, p=0.027, respectively). According to MSI status, a subgroup of MSI-negative and low ATM expression cases exhibited the worst prognosis for DFS and OS; this subgroup also exhibited poorer DFS according to multivariable analysis (HR=1.8, 95% CI, 1.2-2.8, p=0.010), although prognostic value of ATM expression alone did not remain in the multivariable analysis. Taken together, these findings indicate that ATM expression with MSI status is an independent factor for gastric cancer prognosis in gastric cancer patients who received curative surgery. © 2013 Wiley Periodicals, Inc.
    International Journal of Cancer 05/2013; · 6.20 Impact Factor
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    ABSTRACT: BACKGROUND: We aimed to investigate the role of BRCA1 nuclear expression in sporadic gastric cancer; currently, the role remains unknown. METHODS: Patients with gastric cancer who received curative operation with D2 dissection were enrolled in this study. Adjuvant chemotherapy was administered at the discretion of the physician. According to BRCA1 nuclear expression analysis by immunohistochemistry (IHC) on tissue microarrays using anti-BRCA1 antibody MS110, BRCA1 expression was classified as negative, low expression, and high expression. RESULTS: Among 318 cases, 155 cases (48.7 %) were identified as BRCA1-negative by IHC and 96 cases (30.2 %) revealed BRCA1 low expression, 67 cases (21.0 %) showed BRCA1 high expression. The negative or reduced expression of BRCA1 was more frequent in more advanced-stage disease (p < 0.001) and was associated with perineural invasion (p = 0.032). Disease-free survival (DFS) was significantly decreased with reduced BRCA1 expression (p = 0.027). This tendency was also observed in overall survival (OS), although the difference was not significant. The poorer prognosis of BRCA1-negative tumors was overcome through adjuvant chemotherapy. The benefit of adjuvant chemotherapy for DFS and OS in stage III was enhanced only in BRCA1-negative tumors (p < 0.001, p < 0.001, respectively), but not in BRCA1-positive tumors (p = 0.236, p = 0.148, respectively). CONCLUSION: The reduction of BRCA1 nuclear expression is associated with advanced stage and perineural invasion. Moreover, negative BRCA1 nuclear expression is a predictive marker regarding the benefit of adjuvant chemotherapy in sporadic gastric cancer; these novel findings are of great importance, and further, larger studies are warranted.
    Cancer Chemotherapy and Pharmacology 04/2013; · 2.80 Impact Factor
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    ABSTRACT: PURPOSE: To report survival outcomes in patients with neuroendocrine tumor (NET) with hepatic metastasis who were treated by transcatheter arterial chemoembolization and determine prognostic factors that affect clinical outcome. MATERIALS AND METHODS: Patients with NET with hepatic metastasis who underwent chemoembolization between April 2002 and July 2011 were included in this single-center, retrospective study. Progression-free survival (PFS) and overall survival (OS) were calculated by Kaplan-Meier method. The influence of possible prognostic factors on survival was analyzed by log-rank method and multivariate Cox proportional-hazards method. RESULTS: Forty-six patients with hepatic metastasis from nonpancreatic NETs (npNETs; n = 24) or pancreatic NETs (pNETs; n = 22) were included. The median PFS and OS times for the entire group were 16.2 and 38.6 months, respectively, and response rate was 58.1%. Patients with npNET had a similar PFS (17.4 mo vs 15.3 mo) and longer OS (55.0 mo vs 27.6 mo) compared with those with pNET, but there were no significant differences in PFS and OS between groups (P = .398 and P = .375, respectively). By univariate analysis, enterobiliary communication, hepatic tumor burden, and extrahepatic metastasis before the first chemoembolization were significant prognostic factors for poor OS (P = .001, P = .010, and P<.0001, respectively). By multivariate analysis, the same prognostic factors were significant and had relative risks of 4.63, 2.71, and 5.09, respectively. CONCLUSIONS: Transcatheter arterial chemoembolization is an effective treatment modality for hepatic metastasis from NETs, with a median OS of 38.6 months and response rate of 58%. Enterobiliary communication, large hepatic tumor burden, and extrahepatic metastasis were significant risk factors for poor survival outcome.
    Journal of vascular and interventional radiology: JVIR 04/2013; · 1.81 Impact Factor
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    ABSTRACT: PURPOSE: Recently, the American Joint Committee on Cancer (AJCC) 7th edition proposed new response criteria for neoadjuvant chemotherapy (NAC) in breast cancer. The purpose of this study was to evaluate the clinical usefulness of AJCC response criteria. METHODS: A total of 398 consecutive stage II or III breast cancer patients who received NAC were enrolled in this study. AJCC response criteria were as follows: (1) complete response (CR)-absence of invasive carcinoma in the breast and node; (2) partial response (PR)-decrease in either or both T or N stage; (3) no response (NR)-no change or increase in either or both T or N stage. RESULTS: Complete response, PR, and NR by AJCC criteria were 9.8, 59.3, and 30.7 %, respectively. Among the 398 patients, 337 patients were available for both paired pre- and post- breast MRI and chest CT. AJCC response criteria were significantly associated with RECIST criteria (P < 0.001). AJCC response was significantly associated with relapse-free survival (RFS) and overall survival (OS). The 5-year RFS rates were 89.6 % in CR, 74.1 % in PR, and 62.6 % in NR (P = 0.002). The 5-year OS rates were 97.4 % in CR, 88.6 % in PR, and 78.3 % in NR (P = 0.012). When adjusting potential prognostic factors, AJCC response was independently associated with RFS and OS. CONCLUSIONS: AJCC response criteria for NAC in breast cancer have clinical usefulness in evaluating response of NAC, as well as predicting survival. AJCC response criteria can discriminate among patient subgroups with respect to survival.
    Annals of Surgical Oncology 03/2013; · 4.12 Impact Factor
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    ABSTRACT: A poly (ADP-ribose) polymerase (PARP) inhibitor is a rationally designed targeted therapy for cancers with impaired DNA repair abilities. RAD51C is a paralog of RAD51 that has an important role in the DNA damage response. We found that cell lines sensitive to a novel oral PARP inhibitor, olaparib, had low levels of RAD51C expression using microarray analysis, and we therefore hypothesized that low expression of RAD51C may hamper the DNA repair process, resulting in increased sensitivity to olaparib. Compared to the cells with normal RAD51C expression levels, RAD51C-deficient cancer cells were more sensitive to olaparib, and a higher proportion underwent cell death by inducing G2/M cell cycle arrest and apoptosis. The restoration of RAD51C in a sensitive cell line caused attenuation of olaparib sensitivity. In contrast, silencing of RAD51C in a resistant cell line enhanced the sensitivity to olaparib, and the number of RAD51 foci decreased with ablated RAD51C expression. We also found the expression of RAD51C was down-regulated in cancer cells due to epigenetic changes and the RAD51C expression was low in some gastric cancer tissues. Furthermore, olaparib significantly suppressed RAD51C-deficient tumor growth in a xenograft model. In summary, RAD51C-deficient cancer cells are highly sensitive to olaparib and offer preclinical proof-of-principle that RAD51C deficiency may be considered a biomarker for predicting the antitumor effects of olaparib.
    Molecular Cancer Therapeutics 03/2013; · 5.60 Impact Factor

Publication Stats

2k Citations
504.53 Total Impact Points

Institutions

  • 2011–2014
    • Seoul National University
      • • Department of Internal Medicine
      • • Medical Research Center
      Sŏul, Seoul, South Korea
    • National and Kapodistrian University of Athens
      • Department of Surgery
      Athens, Attiki, Greece
  • 2005–2014
    • Seoul National University Hospital
      • Department of Internal Medicine
      Sŏul, Seoul, South Korea
  • 2012
    • Korea Institute of Oriental Medicine
      Bucheon, Gyeonggi Province, South Korea
  • 2007–2011
    • Cancer Research Institute
      New York City, New York, United States
  • 2003–2011
    • CHA University
      • • Department of Internal Medicine
      • • College of Medicine
      • • Department of Neurology
      Seoul, Seoul, South Korea
  • 2009
    • National Cancer Center Korea
      Kōyō, Gyeonggi Province, South Korea
  • 2008
    • The Seoul Institute
      Sŏul, Seoul, South Korea
    • Seoul National University Bundang Hospital
      Sŏul, Seoul, South Korea
    • Seoul Veterans Hospital
      Sŏul, Seoul, South Korea