Medicine, South Korea
Medicine, South Korea

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Sundar R.,National University of Singapore | Cho B.-C.,Yonsei Cancer Center | Brahmer J.R.,Sidney Kimmel Comprehensive Cancer Center | Soo R.A.,National University of Singapore
Therapeutic Advances in Medical Oncology | Year: 2015

New insight on the interaction between the immune system and tumor has identified the programmed death-1/programmed death-1 ligand pathway to be a key player in evading host immune response. The immune checkpoint modulator, nivolumab (BMS-936558/ONO-4538), is the first PD-1 inhibitor to gain regulatory approval, for the treatment of patients with unresectable melanoma. This review will discuss results from early phase studies of nivolumab in solid tumors including non-small cell lung cancer (NSCLC) as well as studies of nivolumab in combination with chemotherapy, other immune modulators and molecular targeted therapy in patients with NSCLC. © The Author(s), 2015.


Sundar R.,National University of Singapore | Soong R.,National University of Singapore | Cho B.-C.,Yonsei Cancer Center | Brahmer J.R.,Sidney Kimmel Comprehensive Cancer Center | And 2 more authors.
Lung Cancer | Year: 2014

Advances in the understanding of the role of the immune system in tumor immunosurveillance have resulted in the recognition that tumors can evade immune destruction via the dysregulation of co-inhibitory or checkpoint signals. This has led to the development of a generation immunotherapeutic agents targeting the immune checkpoint pathway. Recent early phase studies of immune checkpoint modulators, such as CTLA-4, PD-1 and PD-L1 inhibitors in NSCLC have reported promising results with prolonged clinical responses and tolerable toxicity. This article provides an overview of co-stimulatory and inhibitory molecules that regulate the immune response to tumors, recent therapies that have been developed to exploit these interactions and the role of predictive biomarkers in treatment selection. © 2014 Elsevier Ireland Ltd.


Tan C.-S.,National University of Singapore | Cho B.-C.,Yonsei Cancer Center | Soo R.A.,National University of Singapore | Soo R.A.,University of Western Australia
Lung Cancer | Year: 2016

Since the discovery of sensitizing EGFR mutations as a predictive marker of sensitivity to EGFR tyrosine kinase inhibitors (TKIs), the field of targeted therapy in non-small cell lung cancer (NSCLC) has been revolutionized. Patients harbouring these sensitizing mutations treated with EGFR TKI have derived significant clinical outcome when compared with standard platinum based chemotherapy doublets. However disease progression invariably occurs at a median of about 9-13 months from initiation treatment, if acquired resistance commonly due to the development of EGFR T790M mutation. A novel class of "third generation" EGFR TKIs have been developed that is sensitising and T790M mutant-specific whilst sparing WT EGFR, representing a significant breakthrough in the treatment in NSCLC patients with acquired resistance harboring these genotypes. Early phase clinical data suggest the third generation EGFR TKIs such as osimertinib, rociletinib, and HM61713 are highly efficacious and well tolerated. Another promising class of EGFR TKI such as AZD3759 has been designed to penetrate blood brain barrier to treat brain metastases and leptomeningeal disease and has showed promising responses in patients with brain metastases. Acquired resistance to third generation EGFR TKIs has been reported including EGFR C797S. Given its non-invasive nature, plasma ctDNA is being explored as a possible approach to detect T790M mutation and to also inform on novel molecular mechansims of tertiary resistance to third generation EGFR TKIs. An understanding of the mechanisms of acquired resistance to the third-generation EGFR TKIs will greatly aid in the development of the next generation of EGFR TKIs. © 2016 Elsevier Ireland Ltd.


Soo R.A.,National University of Singapore | Soo R.A.,National University Hospital Singapore | Loh M.,National University of Singapore | Loh M.,University of Western Australia | And 6 more authors.
Journal of Thoracic Oncology | Year: 2011

Introduction: Although interethnic differences in survival to cytotoxic chemotherapy in patients with non-small cell lung cancer exist, an analysis of survival outcomes based on ethnicity has not yet been fully evaluated systematically using large patient cohorts. Furthermore, recent trial results may be confounded by the use of the epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI). Methods: A meta-analysis was performed using trials identified through MEDLINE. Summary data on median overall survival (OS), time to progression, progression-free survival, and overall response rate (ORR) were collected from randomized controlled trials. Outcomes were compared between Asian and Caucasian studies. Results: Of the 1182 citations identified, 391 treatment arms (Asian 90 and Caucasian 301) were analyzed. The median OS and ORR in Asian and Caucasian studies for all chemotherapy regimens was 10.1 and 8.0 months (p < 0.001) and 32.2 and 25.9% (p < 0.001), respectively. The median OS in Asian and Caucasian studies for monotherapy, platinum doublets, and three drugs or more combination was 9.9 and 6.8 months, 10.4 and 8.6 months, and 9.4 and 8.0 months, respectively (all p < 0.001). In studies published pre-EGFR TKI, the median OS and ORR in Asian and Caucasian studies for all chemotherapy regimens was 9.1 versus 7.3 months (p < 0.001), respectively, and 29.0 and 23.0% (p < 0.006), respectively. The median OS in Asian and Caucasian studies for monotherapy, platinum doublets, and three drugs or more combination pre-EGFR TKI was 8.9 and 6.5 months (p < 0.005), 9.1 and 7.5 months (p < 0.001), and 9.3 and 7.6 months (p < 0.003), respectively. In third-generation platinum doublets, the median OS in Asian and Caucasian studies was 11.3 and 9.5 months (p < 0.001), respectively, and ORR was 35.0 and 29.8% (p < 0.001), respectively. Conclusion: Ethnic differences in survival and response rate to chemotherapy exist and should be considered in clinical trial designs especially in the global context. Copyright © 2011 by the International Association for the Study of Lung Cancer.


Wang H.-Y.,M Technology Inc. | Ahn S.,Yonsei University | Kim S.,Yonsei University | Park S.,Yonsei University | And 4 more authors.
Experimental and Molecular Pathology | Year: 2014

Circulating tumor cells (CTCs) are an independent prognostic factor for patients with breast cancer. However, the role of CTCs in early breast cancer management is not yet clearly defined. The aim of this study was to isolate and characterize CTCs in blood sample of a breast cancer patient as a biomarker for monitoring treatments efficacy. In this study, 692 blood samples from 221 breast cancer patients and 376 healthy individuals was used to detect CTCs with multiple markers including epithelial cell adhesion molecule (EpCAM), cytokeratin (CK) 19, human epidermal growth factor (HER) 2, Ki67, human telomerase reverse transcriptase (hTERT), and vimentin using quantitative reverse transcription PCR (RT-qPCR). A total of 153 (69.2%) blood samples of 221 patients with breast cancer were found to be positive for at least one of the cancer-associated marker gene before treatment. After chemotherapy, no CTCs were found in 28 (33.3%) of the 84 blood samples analyzed for the presence of CTCs using the RT-qPCR, whereas 56 (66.7%) blood samples were still found to be positive for at least one of the markers. After completing the therapy, the CTC positivity rate decreased to 7 (20.6%) in the neoadjuvant group, whereas this increased to 7 (14%) cases in the adjuvant group. There was no statistically significant relationship between TNM stage and detection of CTC-related markers. Data from this study suggest that RT-qPCR assay for the detection of CTC markers might be useful in selecting appropriate therapeutics and for monitoring treatment efficacy in breast cancer patients. © 2014 Elsevier Inc.


Lee Y.,Center for Lung Cancer | Shim H.S.,Yonsei University | Park M.S.,Yonsei University | Kim J.-H.,Yonsei University | And 4 more authors.
Clinical Cancer Research | Year: 2012

Purpose: This study aimed to search for predictors of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKI) efficacy in previously treated patients with advanced squamous cell lung carcinoma in which EGFR mutations are very rare. Experimental Design: EGFR gene copy numbers were assessed by FISH and evaluated as predictors of EGFR-TKI efficacy in 71 patients with advanced squamous cell lung cancerwhoreceived gefitinib or erlotinib as a second-line or higher therapy. The tumors were classified into EGFR/FISH-positive (high polysomy/ gene amplification) and EGFR/FISH-negative (other) groups. Results: EGFR/FISH was positive in 19 (26.7%) patients. Only EGFR/FISH positive status was correlated with the EGFR-TKIs response (EGFR/FISH + vs. EGFR/FISH -, 26.3% vs. 2.0%; P = 0.005). In a multivariate analysis, the risk of progression was lower in EGFR/FISH-positive patients (HR of EGFR/FISH + vs. EGFR/ FISH -, 0.57; P = 0.057) or patients experiencing grade 2 or more rash (HR for rash grade 2 or more vs. less than 2, 0.54; P = 0.042), compared with EGFR/FISH-negative patients or those experiencing grade of less than 2 rash, respectively. When the combined criteria of EGFR/FISH and skin rash severity were analyzed, EGFR/FISH-negative patients with grade less than 2 rash had poorer clinical outcomes than patients with positive EGFR/FISH or grade 2 or more rash, apparent as a lower response rate (0.0% vs. 21.4%; P = 0.003) and a shorter median progression-free survival (1.13 months vs. 3.90 months; P = 0.0002). Conclusions: EGFR/FISH and skin rash severity may be used to identify which patients are likely to gain a benefit from EGFR-TKIs in this population. ©2012 AACR.


Rha S.Y.,Yonsei University | Park Y.,Eulji University | Song S.K.,Yonsei Cancer Center | Lee C.E.,Yonsei Cancer Center | Lee J.,Eulji University
European journal of oncology nursing : the official journal of European Oncology Nursing Society | Year: 2015

PURPOSE: The role of family caregivers in cancer care continues to expand, and it has been suggested that the caregiving influences health-promoting behaviors. The purpose was to describe the caregiving burden and health-promoting behaviors of the family caregivers of cancer patients and to determine the relationship between caregiving burden and health-promoting behaviors.METHOD: A cross-sectional descriptive study was conducted involving 227 family caregivers of adult cancer patients. Caregiving burden was measured using the Korean version of the Zarit Burden Interview (K-ZBI), and health-promoting behaviors were determined using structured questionnaires.RESULTS: Considerable burden was experienced by the caregivers of cancer patients (K-ZBI score of 36.51 ± 12.54, mean ± SD). However, caregiving burden did not influence caregivers' physical activity, diet, smoking, alcohol consumption, or adherence to cancer screening tests. When the caregivers were compared to controls from the Korea National Health and Nutrition Examination Survey V utilizing adjusted proportions, caregivers were less likely to perform physical activities (16.0% vs. 29.1%, p < 0.001), but more likely to adhere to alcohol consumption recommendations (76.3% vs. 35.0%, p < 0.001) and receive cancer screening services for stomach (68.5% vs. 56.8%, p < 0.011), breast (81.4% vs. 58.8%, p < 0.001), and cervical cancer (75.3% vs. 55.0%, p < 0.001).CONCLUSIONS: The caregivers of cancer patients reported considerable caregiving burden. However the burden was not associated with health-promoting behaviors. Physical inactivity among caregivers may require interventions to promote health of caregivers.IMPLICATIONS FOR PRACTICE: Relieving caregiving burden and improving caregivers' physical activities need to be considered as separate care issues in planning interventions for caregivers of cancer patients. Copyright © 2014 Elsevier Ltd. All rights reserved.


Kim H.S.,Yonsei University | Kim S.C.,Korea Research Institute of Bioscience and Biotechnology | Kim S.J.,Yonsei University | Park C.H.,Yonsei University | And 5 more authors.
BMC Genomics | Year: 2012

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 including ACTN1, CCND1, HCLS1, ITGB5, PFN2, PTPRC, RAB13, and WAS, 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. © 2012 Kim et al.; licensee BioMed Central Ltd.


Kim C.G.,Yonsei Cancer Center
British Journal of Cancer | Year: 2016

Background:Among colorectal cancers (CRCs), high-frequency microsatellite instability (MSI-H) is associated with a better prognosis, compared with low-frequency MSI or microsatellite stability (MSI-L/MSS). However, it is unclear whether MSI affects the prognosis of recurrent CRCs.Methods:This study included 2940 patients with stage I–III CRC who underwent complete resection. The associations of MSI status with recurrence patterns, disease-free survival (DFS), overall survival from diagnosis to death (OS1), and overall survival from recurrence to death (OS2) were analysed.Results:A total of 261 patients (8.9%) had MSI-H CRC. Patients with MSI-H CRC had better DFS, compared to patients with MSI-L/MSS CRC (hazard ratio (HR): 0.619, P<0.001). High-frequency microsatellite instability CRC was associated with more frequent local recurrence (30.0% vs 12.0%, P=0.032) or peritoneal metastasis (40.0% vs 12.3%, P=0.003), and less frequent lung (10.0% vs 42.5%, P=0.004) or liver metastases (15.0% vs 44.7%, P=0.01). Recurrent MSI-H CRC was associated with worse OS1 (HR: 1.363, P=0.035) and OS2 (HR: 2.667, P<0.001). An analysis of patients with colon cancer yielded similar results.Conclusions:Recurrence patterns differed between MSI-H CRC and MSI-L/MSS CRC, and recurrent MSI-H CRCs had a worse prognosis.British Journal of Cancer advance online publication 26 May 2016; doi:10.1038/bjc.2016.161 www.bjcancer.com. © 2016 Cancer Research UK


Lee Y.J.,Yonsei Cancer Center | Cho B.C.,Yonsei Cancer Center | Jee S.H.,Yonsei Cancer Center | Moon J.W.,Yonsei Cancer Center | And 6 more authors.
Journal of Clinical Oncology | Year: 2010

Purpose: Active tobacco smoking has been associated with the incidence of epidermal growth factor receptor (EGFR) mutations. However, the impact of environmental tobacco smoke (ETS) on EGFR mutations has been unknown. We investigated an association between ETS exposure and EGFR mutations in never smokers with non-small-cell lung cancer (NSCLC). Patients and Methods: We enrolled 179 consecutive never smokers who were newly diagnosed with NSCLC. The history of ETS exposure was obtained with a standardized questionnaire that included exposure period, place, and duration. The nucleotide sequences of exons 18 to 21 on EGFR gene were determined using nested polymerase chain reaction amplification. Results: The incidence of EGFR mutations was significantly lower in patients with ETS exposure than in those without (38.5% v 61.4%; P = .008). In a logistic regression model that adjusted for sex and histology, an adjusted odds ratio (AOR) for the risk of EGFR mutations with exposure to ETS was 0.40 (95% CI, 0.20 to 0.81; P = .011). In quartile groups based on total smoker-year, the AORs for the lowest- to highest-quartile groups were 0.59 (95% CI, 0.23 to 1.49), 0.50 (95% CI, 0.17 to 1.50), 0.48 (95% CI, 0.20 to 1.18), and 0.22 (95% CI, 0.08 to 0.62; Ptrend = .028). Among the types of ETS exposure, adulthood ETS and household ETS were significantly associated with the incidence of EGFR mutations. Patients with ETS exposure showed a lower response rate to EGFR tyrosine kinase inhibitors than did patients without ETS exposure (24.6% v 44.8%; P = .053). Conclusion: ETS exposure is negatively associated with EGFR mutations in never smokers with NSCLC. © 2009 by American Society of Clinical Oncology.

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