- Email: [email protected]
P3.02-030 Inhibitory Effects of Mitochondrial TRAP1 on Gefitinib-Resistance in Non-Small Lung Cancer Cells
S2248
P3.02-029 218 Cases of EGFR/ALK Gene Status Analysis in Chinese Lung Squamous Cell Carcinoma C. Xu,1 W. Wang,2 W. Zhuang,3 Z. Song,2 Y. Chen,1 G. Chen,1 M. Fang,2 T. Lv,4 Y. Song4 1Pathology, Fujian Provincial Cancer Hospital, Fuzhou/CN, 2Zhejiang Cancer Hospital, Hangzhou/CN, 3Medical Oncology, Fujian Provincial Cancer Hospital, Fuzhou/CN, 4Department of Respiratory Medicine, Jinling Hospital, Nanjing University School of Medicine, Nanjing/CN Background: Due to the low frequency of EGFR mutation and ALK fusion gene in lung squamous cell carcinoma. Thus the efficacy of icotinib and crizotinib for these patients is not well known. The aim of this study is to investigate the mutations of EGFR gene and ALK fusion gene in lung squamous cell carcinoma. Method: The reverse transcription polymerase chain reaction (RT-PCR) method was used to detect the tissues in 218 patients of lung squamous cell carcinoma with paraffin tissue EGFR gene mutation and ALK fusion gene. Result: The total mutation rate in 218 patients of squamous cell carcinoma was 54.71% (151/276). EGFR gene mutation rate was 2.29% (5/218), which was both found in 19del and L858R, ALK fusion gene positive rate was 6.14% (7/114). Conclusion: There are a certain proportion of EGFR gene mutation and ALK fusion gene in lung squamous cell carcinoma, and the detection the EGFR gene mutation and ALK fusion gene cannot be ignored in squamous cell carcinoma. Keywords: EGFR gene, Squamous cell carcinoma, ALK gene
P3.02-030 Inhibitory Effects of Mitochondrial TRAP1 on Gefitinib-Resistance in Non-Small Lung Cancer Cells E. Jeong, K. Hwang Internal Medicine, Wonkwang University Hospital, Iksan,jeonbuk/KR Background: TNF receptor-associated protein 1 (TRAP1) has been reported to be upregulated in some tumors, and protected against apoptosis and oxidative stress. This study was designed to investigate overcoming gefitinib resistance in NSCLC through a mechanism-based approach using gamitrinib variant containing triphenylphosphonium (G-TPP), TRAP1 inhibitor. Method: We developed an in vitro model of acquired resistance to gefitinib by continuously treating HCC827 with escalating doses. The effects of G-TPP on apoptosis and ROS-dependent mitochondrial dysfunction in HCC827GR cells were examined by annexin V binding assay, MitoSoX, and immunoblot analysis and we tested the effects of pretreated with NAC or DPI, free radical scavenger. In addition, TRAP1 and antioxidant MnSOD were respectively knocked down or overexpressed to determine its role in modulating ROSmediated apotosis signals by G-TPP. Result: Downregulation of TRAP1 through siRNA or G-TPP enhanced ROS-mediated apoptosis whereas TRAP1 overexpression attenuated ROS-mediated apoptosis induced by gefitinib. On the other hand, pretreatment with NAC or DPI prevents apoptosis induced by gefitinib and G-TPP. We next showed that the combination of gefitinib and G-TPP resulted in decreased expression of MnSOD in HCC827GR cells, not HCC827 cells. MnSOD siRNA and combined with gefitinib and G-TPP resulted in a greater apoptosis. In contrast, overexpression of MnSOD could confer protection against the apoptosis reduced by gefitinib and G-TPP. Conclusion: TRAP1 downregulation could overcome gefitinib resistance in NSCLC via ROSmediated apoptotic pathway. Moreover, enhanced apoptosis by gefitinib and G-TPP in HCC827GR cells was due, at least in part, to the downregulation of MnSOD. Keywords: TRAP1, Gefitinib resistance, Lung cancer
Journal of Thoracic Oncology
Vol. 12 No. 11S2
P3.02-031 Detection of Activating EGFR Mutations and Resistant T790M Mutation from cfDNA in Malignant Pleural Effusion(MPE-DNA) K. Lee,1 O.S.h. Chan,2 T. Mok,1 A. Chan,3 C. Lee,4 A. Fontela,4 T. Yung,5 V. Chan,1 A. Wong,1 K.H. Wong,1 S. Fung,3 W. Gai3 1Clinical Oncology, Prince of Wales Hospital, Chinese University of Hong Kong, Hong Kong/HK, 2Department of Clinical Oncology, Pamela Youde Nethersole Eastern Hospital, Hong Kong/HK, 3Chemical Pathology, Prince of Wales Hospital, Chinese University of Hong Kong, Hong Kong/HK, 4 Clinical Research Unit, St. George Hospital, Sydney, Kogarah/NSW/AU, 5 Sanomics Limited Hong Kong, Hong Kong/HK Background: Analysis of activating EGFR and resistant T790M mutations from plasma cfDNA is now recognized as one of the standard testing methods in clinical practice.(Mok et al CCR 2015, Oxnard et al JCO 2016) Sensitivity varies from 60 to 80% while specificity is above 90%. Malignant pleural effusion (MPE) is an alternative rich source of cfDNA and efficacy of mutation testing from this sample source remains unclear. Method: Objectives of this study is to study the feasibility of testing EGFR mutations using MPE-DNA and to compare the diagnostic utilities with plasma cfDNA in lung cancer patients with known EGFR mutation status established by tumor tissue. 10 ml of blood and 10 ml of pleural fluid were collected after consent. DNA was extracted and tested by digital PCR (Sanomics Inc. Hong Kong, China). Result: We enrolled 45 patients between November 2016 and May 2017. Patient demographics are summarized as follows: male (n¼21) vs female (n¼24); tissue EGFR wild type (n¼13) vs mutation (n¼24) vs unknown (n¼8); treatment naïve (n¼26) vs progression of TKI (n¼19). Diagnostic utilities are summarized in table below. 9 plasma samples were positive for T790M compared to 14 samples of MPE-DNA being positive. (Detection rate: 0.20 vs 0.31, respectively) Total of 6 negative T790M plasma samples were tested positive in MPE-DNA, and vice versa, 2 samples. Concordance rate of T790M testing between plasma cfDNA and MPE-DNA is 0.82. Conclusion: It is feasible to detect activating EGFR and resistant T790M mutations from MPE-DNA. Sensitivity of testing MPE-DNA is similar if not better than plasma cfDNA. Further investigation is warranted. Keywords: EGFR, cell-free DNA, biomarker EGFR mutation
Sensitivity Specificity Concordance Mean allele frequency of cfDNA only (range)
Plasma cfDNA vs tumor
MPE-DNA vs tumor
0.83 0.92 32/37¼0.86 13.43% (0.10%-58.66%)
0.92 0.92 34/37¼ 0.92 31.77% (1.21%-83.40%)
P3.02-032 Spatial Heterogeneity of EGFR and KRAS Variant Allele Frequencies Correlates with Histological Patterns of Lung Adenocarcinomas S. Dietz,1 A. Harms,2 V. Endris,2 F. Eichhorn,3 M. Kriegsmann,2 R. Longuespée,2 A. Stenzinger,2 A. Warth,4 D. Kazdal,2 H. Sültmann1 1 Cancer Genome Research Group, German Cancer Research Center (Dkfz) and National Center for Tumor Diseases (Nct), Heidelberg/DE, 2 University Hospital Heidelberg, Institute of Pathology, Heidelberg/DE, 3 Department of Thoracic Surgery, Thoraxklinik at the University Hospital Heidelberg, Heidelberg/DE, 4Translational Lung Research Center (TLRC) Heidelberg, German Center for Lung Research (DZL), Heidelberg/DE
P3.02-029 218 Cases of EGFR/ALK Gene Status Analysis in Chinese Lung Squamous Cell Carcinoma C. Xu,1 W. Wang,2 W. Zhuang,3 Z. Song,2 Y. Chen,1 G. Chen,1 M. Fang,2 T. Lv,4 Y. Song4 1Pathology, Fujian Provincial Cancer Hospital, Fuzhou/CN, 2Zhejiang Cancer Hospital, Hangzhou/CN, 3Medical Oncology, Fujian Provincial Cancer Hospital, Fuzhou/CN, 4Department of Respiratory Medicine, Jinling Hospital, Nanjing University School of Medicine, Nanjing/CN Background: Due to the low frequency of EGFR mutation and ALK fusion gene in lung squamous cell carcinoma. Thus the efficacy of icotinib and crizotinib for these patients is not well known. The aim of this study is to investigate the mutations of EGFR gene and ALK fusion gene in lung squamous cell carcinoma. Method: The reverse transcription polymerase chain reaction (RT-PCR) method was used to detect the tissues in 218 patients of lung squamous cell carcinoma with paraffin tissue EGFR gene mutation and ALK fusion gene. Result: The total mutation rate in 218 patients of squamous cell carcinoma was 54.71% (151/276). EGFR gene mutation rate was 2.29% (5/218), which was both found in 19del and L858R, ALK fusion gene positive rate was 6.14% (7/114). Conclusion: There are a certain proportion of EGFR gene mutation and ALK fusion gene in lung squamous cell carcinoma, and the detection the EGFR gene mutation and ALK fusion gene cannot be ignored in squamous cell carcinoma. Keywords: EGFR gene, Squamous cell carcinoma, ALK gene
P3.02-030 Inhibitory Effects of Mitochondrial TRAP1 on Gefitinib-Resistance in Non-Small Lung Cancer Cells E. Jeong, K. Hwang Internal Medicine, Wonkwang University Hospital, Iksan,jeonbuk/KR Background: TNF receptor-associated protein 1 (TRAP1) has been reported to be upregulated in some tumors, and protected against apoptosis and oxidative stress. This study was designed to investigate overcoming gefitinib resistance in NSCLC through a mechanism-based approach using gamitrinib variant containing triphenylphosphonium (G-TPP), TRAP1 inhibitor. Method: We developed an in vitro model of acquired resistance to gefitinib by continuously treating HCC827 with escalating doses. The effects of G-TPP on apoptosis and ROS-dependent mitochondrial dysfunction in HCC827GR cells were examined by annexin V binding assay, MitoSoX, and immunoblot analysis and we tested the effects of pretreated with NAC or DPI, free radical scavenger. In addition, TRAP1 and antioxidant MnSOD were respectively knocked down or overexpressed to determine its role in modulating ROSmediated apotosis signals by G-TPP. Result: Downregulation of TRAP1 through siRNA or G-TPP enhanced ROS-mediated apoptosis whereas TRAP1 overexpression attenuated ROS-mediated apoptosis induced by gefitinib. On the other hand, pretreatment with NAC or DPI prevents apoptosis induced by gefitinib and G-TPP. We next showed that the combination of gefitinib and G-TPP resulted in decreased expression of MnSOD in HCC827GR cells, not HCC827 cells. MnSOD siRNA and combined with gefitinib and G-TPP resulted in a greater apoptosis. In contrast, overexpression of MnSOD could confer protection against the apoptosis reduced by gefitinib and G-TPP. Conclusion: TRAP1 downregulation could overcome gefitinib resistance in NSCLC via ROSmediated apoptotic pathway. Moreover, enhanced apoptosis by gefitinib and G-TPP in HCC827GR cells was due, at least in part, to the downregulation of MnSOD. Keywords: TRAP1, Gefitinib resistance, Lung cancer
Journal of Thoracic Oncology
Vol. 12 No. 11S2
P3.02-031 Detection of Activating EGFR Mutations and Resistant T790M Mutation from cfDNA in Malignant Pleural Effusion(MPE-DNA) K. Lee,1 O.S.h. Chan,2 T. Mok,1 A. Chan,3 C. Lee,4 A. Fontela,4 T. Yung,5 V. Chan,1 A. Wong,1 K.H. Wong,1 S. Fung,3 W. Gai3 1Clinical Oncology, Prince of Wales Hospital, Chinese University of Hong Kong, Hong Kong/HK, 2Department of Clinical Oncology, Pamela Youde Nethersole Eastern Hospital, Hong Kong/HK, 3Chemical Pathology, Prince of Wales Hospital, Chinese University of Hong Kong, Hong Kong/HK, 4 Clinical Research Unit, St. George Hospital, Sydney, Kogarah/NSW/AU, 5 Sanomics Limited Hong Kong, Hong Kong/HK Background: Analysis of activating EGFR and resistant T790M mutations from plasma cfDNA is now recognized as one of the standard testing methods in clinical practice.(Mok et al CCR 2015, Oxnard et al JCO 2016) Sensitivity varies from 60 to 80% while specificity is above 90%. Malignant pleural effusion (MPE) is an alternative rich source of cfDNA and efficacy of mutation testing from this sample source remains unclear. Method: Objectives of this study is to study the feasibility of testing EGFR mutations using MPE-DNA and to compare the diagnostic utilities with plasma cfDNA in lung cancer patients with known EGFR mutation status established by tumor tissue. 10 ml of blood and 10 ml of pleural fluid were collected after consent. DNA was extracted and tested by digital PCR (Sanomics Inc. Hong Kong, China). Result: We enrolled 45 patients between November 2016 and May 2017. Patient demographics are summarized as follows: male (n¼21) vs female (n¼24); tissue EGFR wild type (n¼13) vs mutation (n¼24) vs unknown (n¼8); treatment naïve (n¼26) vs progression of TKI (n¼19). Diagnostic utilities are summarized in table below. 9 plasma samples were positive for T790M compared to 14 samples of MPE-DNA being positive. (Detection rate: 0.20 vs 0.31, respectively) Total of 6 negative T790M plasma samples were tested positive in MPE-DNA, and vice versa, 2 samples. Concordance rate of T790M testing between plasma cfDNA and MPE-DNA is 0.82. Conclusion: It is feasible to detect activating EGFR and resistant T790M mutations from MPE-DNA. Sensitivity of testing MPE-DNA is similar if not better than plasma cfDNA. Further investigation is warranted. Keywords: EGFR, cell-free DNA, biomarker EGFR mutation
Sensitivity Specificity Concordance Mean allele frequency of cfDNA only (range)
Plasma cfDNA vs tumor
MPE-DNA vs tumor
0.83 0.92 32/37¼0.86 13.43% (0.10%-58.66%)
0.92 0.92 34/37¼ 0.92 31.77% (1.21%-83.40%)
P3.02-032 Spatial Heterogeneity of EGFR and KRAS Variant Allele Frequencies Correlates with Histological Patterns of Lung Adenocarcinomas S. Dietz,1 A. Harms,2 V. Endris,2 F. Eichhorn,3 M. Kriegsmann,2 R. Longuespée,2 A. Stenzinger,2 A. Warth,4 D. Kazdal,2 H. Sültmann1 1 Cancer Genome Research Group, German Cancer Research Center (Dkfz) and National Center for Tumor Diseases (Nct), Heidelberg/DE, 2 University Hospital Heidelberg, Institute of Pathology, Heidelberg/DE, 3 Department of Thoracic Surgery, Thoraxklinik at the University Hospital Heidelberg, Heidelberg/DE, 4Translational Lung Research Center (TLRC) Heidelberg, German Center for Lung Research (DZL), Heidelberg/DE