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1.  BRAF Fusions Define a Distinct Molecular Subset of Melanomas with Potential Sensitivity to MEK Inhibition 
Purpose
Recurrent “driver” mutations at specific loci in BRAF, NRAS, KIT, GNAQ, and GNA11 define clinically-relevant molecular subsets of melanoma, but >30% are “pan-negative” for these recurrent mutations. We sought to identify additional potential drivers in “pan-negative” melanoma.
Experimental Design
Using a targeted next-generation sequencing (NGS) assay (FoundationOne™) and targeted RNA sequencing, we identified a novel PAPSS1-BRAF fusion in a “pan-negative” melanoma. We then analyzed NGS data from 51 additional melanomas genotyped by FoundationOne™, as well as melanoma RNA, whole genome and whole exome sequencing data in The Cancer Genome Atlas (TCGA), to determine the potential frequency of BRAF fusions in melanoma. We characterized the signaling properties of confirmed molecular alterations by ectopic expression of engineered cDNAs in 293H cells.
Results
Activation of the mitogen-activated protein kinase (MAPK) pathway in cells by ectopic expression of PAPSS1-BRAF was abrogated by MEK inhibition but not by BRAF inhibition. NGS data analysis of 51 additional melanomas revealed a second BRAF fusion (TRIM24-BRAF) in a “pan-negative” sample; MAPK signaling induced by TRIM24-BRAF was also MEK inhibitor sensitive. Through mining TCGA skin cutaneous melanoma dataset, we further identified two potential BRAF fusions in another 49 “pan-negative” cases.
Conclusions
BRAF fusions define a new molecular subset of melanoma, potentially comprising 4–8% of “pan-negative” cases. Their presence may explain an unexpected clinical response to MEK inhibitor therapy or assist in selecting patients for MEK directed therapy.
doi:10.1158/1078-0432.CCR-13-1746
PMCID: PMC3880773  PMID: 24345920
melanoma; BRAF fusion; BRAF rearrangement; next-generation sequencing; BRAF inhibitor; MEK inhibitor; vemurafenib; trametinib
2.  Enabling a Genetically Informed Approach to Cancer Medicine: A Retrospective Evaluation of the Impact of Comprehensive Tumor Profiling Using a Targeted Next-Generation Sequencing Panel 
The Oncologist  2014;19(6):616-622.
To determine the clinical impact of extensive genetic analysis, the use of a targeted next-generation sequencing (NGS) platform (FoundationOne) in advanced cancer patients was reviewed. Mutational profiling using a targeted NGS panel identified potentially actionable alterations in a majority of the patients. The assay identified additional therapeutic options and facilitated clinical trial enrollment. As time progresses, NGS results will be used to guide therapy in an increasing proportion of patients.
Background.
Oncogenic genetic alterations “drive” neoplastic cell proliferation. Small molecule inhibitors and antibodies are being developed that target an increasing number of these altered gene products. Next-generation sequencing (NGS) is a powerful tool to identify tumor-specific genetic changes. To determine the clinical impact of extensive genetic analysis, we reviewed our experience using a targeted NGS platform (FoundationOne) in advanced cancer patients.
Patients and Methods.
We retrospectively assessed demographics, NGS results, and therapies received for patients undergoing targeted NGS (exonic sequencing of 236 genes and selective intronic sequencing from 19 genes) between April 2012 and August 2013. Coprimary endpoints were the percentage of patients with targeted therapy options uncovered by mutational profiling and the percentage who received genotype-directed therapy.
Results.
Samples from 103 patients were tested, most frequently breast carcinoma (26%), head and neck cancers (23%), and melanoma (10%). Most patients (83%) were found to harbor potentially actionable genetic alterations, involving cell-cycle regulation (44%), phosphatidylinositol 3-kinase-AKT (31%), and mitogen-activated protein kinase (19%) pathways. With median follow-up of 4.1 months, 21% received genotype-directed treatments, most in clinical trials (61%), leading to significant benefit in several cases. The most common reasons for not receiving genotype-directed therapy were selection of standard therapy (35%) and clinical deterioration (13%).
Conclusion.
Mutational profiling using a targeted NGS panel identified potentially actionable alterations in a majority of advanced cancer patients. The assay identified additional therapeutic options and facilitated clinical trial enrollment. As time progresses, NGS results will be used to guide therapy in an increasing proportion of patients.
doi:10.1634/theoncologist.2014-0011
PMCID: PMC4041676  PMID: 24797823
Next-generation sequencing; Genotype; Precision medicine; Molecular targeted therapy; Cancer; Mutation
3.  Using Multiplexed Assays of Oncogenic Drivers in Lung Cancers to Select Targeted Drugs 
IMPORTANCE
Targeting oncogenic drivers (genomic alterations critical to cancer development and maintenance) has transformed the care of patients with lung adenocarcinomas. The Lung Cancer Mutation Consortium was formed to perform multiplexed assays testing adenocarcinomas of the lung for drivers in 10 genes to enable clinicians to select targeted treatments and enroll patients into clinical trials.
OBJECTIVES
To determine the frequency of oncogenic drivers in patients with lung adenocarcinomas and to use the data to select treatments targeting the identified driver(s) and measure survival.
DESIGN, SETTING, AND PARTICIPANTS
From 2009 through 2012, 14 sites in the United States enrolled patients with metastatic lung adenocarcinomas and a performance status of 0 through 2 and tested their tumors for 10 drivers. Information was collected on patients, therapies, and survival.
INTERVENTIONS
Tumors were tested for 10 oncogenic drivers, and results were used to select matched targeted therapies.
MAIN OUTCOMES AND MEASURES
Determination of the frequency of oncogenic drivers, the proportion of patients treated with genotype-directed therapy, and survival.
RESULTS
From 2009 through 2012, tumors from 1007 patients were tested for at least 1 gene and 733 for 10 genes (patients with full genotyping). An oncogenic driver was found in 466 of 733 patients (64%). Among these 733 tumors, 182 tumors (25%) had the KRAS driver; sensitizing EGFR, 122 (17%); ALK rearrangements, 57 (8%); other EGFR, 29 (4%); 2 or more genes, 24 (3%); ERBB2 (formerly HER2), 19 (3%); BRAF, 16 (2%); PIK3CA, 6 (<1%); MET amplification, 5 (<1%); NRAS, 5 (<1%); MEK1, 1 (<1%); AKT1, 0. Results were used to select a targeted therapy or trial in 275 of 1007 patients (28%). The median survival was 3.5 years (interquartile range [IQR], 1.96-7.70) for the 260 patients with an oncogenic driver and genotype-directed therapy compared with 2.4 years (IQR, 0.88-6.20) for the 318 patients with any oncogenic driver(s) who did not receive genotype-directed therapy (propensity score–adjusted hazard ratio, 0.69 [95% CI, 0.53-0.9], P = .006).
CONCLUSIONS AND RELEVANCE
Actionable drivers were detected in 64% of lung adenocarcinomas. Multiplexed testing aided physicians in selecting therapies. Although individuals with drivers receiving a matched targeted agent lived longer, randomized trials are required to determine if targeting therapy based on oncogenic drivers improves survival.
doi:10.1001/jama.2014.3741
PMCID: PMC4163053  PMID: 24846037
4.  Driver mutations among never smoking female lung cancer tissues in China identify unique EGFR and KRAS mutation pattern associated with household coal burning 
Respiratory medicine  2013;107(11):10.1016/j.rmed.2013.08.018.
Lung cancer in never smokers, which has been partially attributed to household solid fuel use (i.e coal), is etiologically and clinically different from lung cancer attributed to tobacco smoking. To explore the spectrum of driver mutations among lung cancer tissues from never smokers, specifically in a population where high lung cancer rates have been attributed to indoor air pollution from domestic coal use, multiplexed assays were used to detect >40 point mutations, insertions, and deletions (EGFR, KRAS, BRAF, HER2, NRAS, PIK3CA, MEK1, AKT1, and PTEN) among the lung tumors of confirmed never smoking females from Xuanwei, China [32 adenocarcinomas (ADCs), 7 squamous cell carcinomas (SCCs), 1 adenosquamous carcinoma (ADSC)]. EGFR mutations were detected in 35% of tumors. 46% of these involved EGFR exon 18 G719X, while 14% were exon 21 L858R mutations. KRAS mutations, all of which were G12C_34G>T, were observed in 15% of tumors. EGFR and KRAS mutations were mutually exclusive, and no mutations were observed in the other tested genes. Most point mutations were transversions and were also found in tumors from patients who used coal in their homes. Our high mutation frequencies in EGFR exon 18 and KRAS and low mutation frequency in EGFR exon 21 are strikingly divergent from those in other smoking and never smoking populations from Asia. Given that our subjects live in a region where coal is typically burned indoors, our findings provide new insights into the pathogenesis of lung cancer among never smoking females exposed to indoor air pollution from coal.
doi:10.1016/j.rmed.2013.08.018
PMCID: PMC3848251  PMID: 24055406
EGFR; KRAS; lung cancer; never smoking; China; driver mutations; tumor tissue
5.  MSEA: detection and quantification of mutation hotspots through mutation set enrichment analysis 
Genome Biology  2014;15(10):489.
Many cancer genes form mutation hotspots that disrupt their functional domains or active sites, leading to gain- or loss-of-function. We propose a mutation set enrichment analysis (MSEA) implemented by two novel methods, MSEA-clust and MSEA-domain, to predict cancer genes based on mutation hotspot patterns. MSEA methods are evaluated by both simulated and real cancer data. We find approximately 51% of the eligible known cancer genes form detectable mutation hotspots. Application of MSEA in eight cancers reveals a total of 82 genes with mutation hotspots, including well-studied cancer genes, known cancer genes re-found in new cancer types, and novel cancer genes.
Electronic supplementary material
The online version of this article (doi:10.1186/s13059-014-0489-9) contains supplementary material, which is available to authorized users.
doi:10.1186/s13059-014-0489-9
PMCID: PMC4226881  PMID: 25348067
6.  Dual Inhibition of EGFR with Afatinib and Cetuximab in Kinase Inhibitor-Resistant EGFR-Mutant Lung Cancer With and Without T790M Mutations 
Cancer discovery  2014;4(9):1036-1045.
EGFR-mutant lung cancers responsive to reversible EGFR inhibitors (gefitinib/erlotinib) develop acquired resistance, mediated by second-site EGFR T790M mutation in >50% cases. Preclinically, afatinib (irreversible ErbB family blocker) plus cetuximab (anti-EGFR monoclonal antibody) overcomes T790M-mediated resistance. This phase Ib study combining afatinib and cetuximab enrolled heavily pretreated patients with advanced EGFR-mutant lung cancer and acquired resistance to erlotinib/gefitinib. Patients provided post-acquired-resistance tumor samples for profiling EGFR mutations. Among 126 patients, objective response rate (overall 29%) was comparable in T790M-positive and T790M-negative tumors (32% vs. 25%; P = 0.341). Median progression-free survival was 4.7 months (95% confidence interval, 4.3–6.4); median duration of confirmed objective response was 5.7 months (range, 1.8–24.4). Therapy-related grade 3/4 adverse events occurred in 44%/2% of patients. Afatinib/cetuximab demonstrated robust clinical activity and a manageable safety profile in EGFR-mutant lung cancers with acquired resistance to gefitinib or erlotinib, both with and without T790M mutations, warranting further investigation.
doi:10.1158/2159-8290.CD-14-0326
PMCID: PMC4155006  PMID: 25074459
afatinib; cetuximab; acquired resistance
7.  Genome-wide association analysis identifies new lung cancer susceptibility loci in never-smoking women in Asia 
Lan, Qing | Hsiung, Chao A | Matsuo, Keitaro | Hong, Yun-Chul | Seow, Adeline | Wang, Zhaoming | Hosgood, H Dean | Chen, Kexin | Wang, Jiu-Cun | Chatterjee, Nilanjan | Hu, Wei | Wong, Maria Pik | Zheng, Wei | Caporaso, Neil | Park, Jae Yong | Chen, Chien-Jen | Kim, Yeul Hong | Kim, Young Tae | Landi, Maria Teresa | Shen, Hongbing | Lawrence, Charles | Burdett, Laurie | Yeager, Meredith | Yuenger, Jeffrey | Jacobs, Kevin B | Chang, I-Shou | Mitsudomi, Tetsuya | Kim, Hee Nam | Chang, Gee-Chen | Bassig, Bryan A | Tucker, Margaret | Wei, Fusheng | Yin, Zhihua | Wu, Chen | An, She-Juan | Qian, Biyun | Lee, Victor Ho Fun | Lu, Daru | Liu, Jianjun | Jeon, Hyo-Sung | Hsiao, Chin-Fu | Sung, Jae Sook | Kim, Jin Hee | Gao, Yu-Tang | Tsai, Ying-Huang | Jung, Yoo Jin | Guo, Huan | Hu, Zhibin | Hutchinson, Amy | Wang, Wen-Chang | Klein, Robert | Chung, Charles C | Oh, In-Jae | Chen, Kuan-Yu | Berndt, Sonja I | He, Xingzhou | Wu, Wei | Chang, Jiang | Zhang, Xu-Chao | Huang, Ming-Shyan | Zheng, Hong | Wang, Junwen | Zhao, Xueying | Li, Yuqing | Choi, Jin Eun | Su, Wu-Chou | Park, Kyong Hwa | Sung, Sook Whan | Shu, Xiao-Ou | Chen, Yuh-Min | Liu, Li | Kang, Chang Hyun | Hu, Lingmin | Chen, Chung-Hsing | Pao, William | Kim, Young-Chul | Yang, Tsung-Ying | Xu, Jun | Guan, Peng | Tan, Wen | Su, Jian | Wang, Chih-Liang | Li, Haixin | Sihoe, Alan Dart Loon | Zhao, Zhenhong | Chen, Ying | Choi, Yi Young | Hung, Jen-Yu | Kim, Jun Suk | Yoon, Ho-Il | Cai, Qiuyin | Lin, Chien-Chung | Park, In Kyu | Xu, Ping | Dong, Jing | Kim, Christopher | He, Qincheng | Perng, Reury-Perng | Kohno, Takashi | Kweon, Sun-Seog | Chen, Chih-Yi | Vermeulen, Roel | Wu, Junjie | Lim, Wei-Yen | Chen, Kun-Chieh | Chow, Wong-Ho | Ji, Bu-Tian | Chan, John K C | Chu, Minjie | Li1, Yao-Jen | Yokota, Jun | Li, Jihua | Chen, Hongyan | Xiang, Yong-Bing | Yu, Chong-Jen | Kunitoh, Hideo | Wu, Guoping | Jin, Li | Lo, Yen-Li | Shiraishi, Kouya | Chen, Ying-Hsiang | Lin, Hsien-Chih | Wu, Tangchun | Wu, Yi-Long | Yang, Pan-Chyr | Zhou, Baosen | Shin, Min-Ho | Fraumeni, Joseph F | Lin, Dongxin | Chanock, Stephen J | Rothman, Nathaniel
Nature genetics  2012;44(12):1330-1335.
To identify common genetic variants that contribute to lung cancer susceptibility, we conducted a multistage genome-wide association study of lung cancer in Asian women who never smoked. We scanned 5,510 never-smoking female lung cancer cases and 4,544 controls drawn from 14 studies from mainland China, South Korea, Japan, Singapore, Taiwan, and Hong Kong. We genotyped the most promising variants (associated at P < 5 × 10-6) in an additional 1,099 cases and 2,913 controls. We identified three new susceptibility loci at 10q25.2 (rs7086803, P = 3.54 × 10-18), 6q22.2 (rs9387478, P = 4.14 × 10-10) and 6p21.32 (rs2395185, P = 9.51 × 10-9). We also confirmed associations reported for loci at 5p15.33 and 3q28 and a recently reported finding at 17q24.3. We observed no evidence of association for lung cancer at 15q25 in never-smoking women in Asia, providing strong evidence that this locus is not associated with lung cancer independent of smoking.
doi:10.1038/ng.2456
PMCID: PMC4169232  PMID: 23143601
8.  DNA-Mutation Inventory to Refine and Enhance Cancer Treatment (DIRECT): A Catalog of Clinically Relevant Cancer Mutations to Enable Genome-Directed Anticancer Therapy 
Purpose
Tumor gene mutation status is becoming increasingly important in the treatment of patients with cancer. A comprehensive catalog of tumor gene–response outcomes from individual patients is needed, especially for actionable mutations and rare variants. We created a proof-of-principle database [DNA-mutation Inventory to Refine and Enhance Cancer Treatment (DIRECT)], starting with lung cancer-associated EGF receptor (EGFR) mutations, to provide a resource for clinicians to prioritize treatment decisions based on a patient’s tumor mutations at the point of care.
Methods
A systematic search of literature published between June 2005 and May 2011 was conducted through PubMed to identify patient-level, mutation–drug response in patients with non–small cell lung cancer (NSCLC) with EGFR mutant tumors. Minimum inclusion criteria included patient’s EGFR mutation, corresponding treatment, and an associated radiographic outcome.
Results
A total of 1,021 patients with 1,070 separate EGFR tyrosine kinase inhibitor therapy responses from 116 different publications were included. About 188 unique EGFR mutations occurring in 207 different combinations were identified: 149 different mutation combinations were associated with disease control and 42 were associated with disease progression. Four secondary mutations, in 16 different combinations, were associated with acquired resistance.
Conclusions
As tumor sequencing becomes more common in oncology, this comprehensive electronic catalog can enable genome-directed anticancer therapy. DIRECT will eventually encompass all tumor mutations associated with clinical outcomes on targeted therapies. Users can make specific queries at http:// www.mycancergenome.org/about/direct to obtain clinically relevant data associated with various mutations.
doi:10.1158/1078-0432.CCR-12-1894
PMCID: PMC4121886  PMID: 23344264
9.  Application of next generation sequencing to human gene fusion detection: computational tools, features and perspectives 
Briefings in Bioinformatics  2012;14(4):506-519.
Gene fusions are important genomic events in human cancer because their fusion gene products can drive the development of cancer and thus are potential prognostic tools or therapeutic targets in anti-cancer treatment. Major advancements have been made in computational approaches for fusion gene discovery over the past 3 years due to improvements and widespread applications of high-throughput next generation sequencing (NGS) technologies. To identify fusions from NGS data, existing methods typically leverage the strengths of both sequencing technologies and computational strategies. In this article, we review the NGS and computational features of existing methods for fusion gene detection and suggest directions for future development.
doi:10.1093/bib/bbs044
PMCID: PMC3713712  PMID: 22877769
gene fusion; next generation sequencing; cancer; whole genome sequencing; transcriptome sequencing; computational tools
10.  Discovery of a mutant-selective covalent inhibitor of EGFR that overcomes T790M-mediated resistance in NSCLC 
Cancer discovery  2013;3(12):1404-1415.
Non-small cell lung cancer (NSCLC) patients with activating epidermal growth factor receptor (EGFR) mutations initially respond to first generation reversible EGFR tyrosine kinase inhibitors. However, clinical efficacy is limited by acquired resistance, frequently driven by the EGFR T790M mutation. CO-1686 is a novel, irreversible and orally delivered kinase inhibitor that specifically targets the mutant forms of EGFR including T790M while exhibiting minimal activity towards the wild-type (WT) receptor. Oral administration of CO-1686 as single agent induces tumor regression in EGFR mutated NSCLC tumor xenograft and transgenic models. Minimal activity of CO-1686 against the WT EGFR receptor was observed. In NSCLC cells with acquired resistance to CO-1686 in vitro, there was no evidence of additional mutations or amplification of the EGFR gene, but resistant cells exhibited signs of epithelial-mesenchymal transition (EMT) and demonstrated increased sensitivity to AKT inhibitors. These results suggest CO-1686 may offer a novel therapeutic option for patients with mutant EGFR NSCLC.
doi:10.1158/2159-8290.CD-13-0314
PMCID: PMC4048995  PMID: 24065731
NSCLC; EGFR; drug resistance; T790M; EMT
11.  Phase II Trial of Gefitinib and Everolimus in Advanced Non-small Cell Lung Cancer 
Introduction
Concurrent signal transduction inhibition with the epidermal growth factor receptor (EGFR) inhibitor gefitinib and the mammalian target-of-rapamycin inhibitor everolimus has been hypothesized to result in enhanced antitumor activity in patients with non-small cell lung cancer (NSCLC). This phase II trial assessed the efficacy of the combination of gefitinib and everolimus in patients with advanced NSCLC.
Methods
Two cohorts of 31 patients with measurable stage IIIB/IV NSCLC were enrolled: (1) no prior chemotherapy and (2) previously treated with cisplatin or carboplatin and docetaxel or pemetrexed. All patients received daily everolimus 5 mg and gefitinib 250 mg. Response was assessed after 1 month and then every 2 months. Pretreatment tumor specimens were collected for mutation testing.
Results
Sixty-two patients were enrolled (median age: 66 years, 50% women, 98% stage IV, all current/former smokers, and 85% adenocarcinoma). Partial responses were seen in 8 of 62 patients (response rate: 13%; 95% confidence interval: 5–21%); five responders had received no prior chemotherapy. Three partial responders had an EGFR mutation. Both patients with a KRAS (G12F) mutation responded. The median time to progression was 4 months. Median overall survival was 12 months, 27 months for no prior chemotherapy patients, and 11 months for patients previously treated with chemotherapy.
Conclusions
The 13% partial response rate observed did not meet the prespecified response threshold to pursue further study of the combination of gefitinib and everolimus. The response rate in patients with non-EGFR mutant tumors was 8%, likely reflecting activity of everolimus. Further investigation of mammalian target-of-rapamycin inhibitors in patients with NSCLC with KRAS G12F-mutated tumors is warranted.
doi:10.1097/JTO.0b013e3181ec1531
PMCID: PMC4020424  PMID: 20871262
Non-small cell lung cancer; Gefitinib; Everolimus.
12.  Morphologic Features of Adenocarcinoma of the Lung Predictive of Response to the Epidermal Growth Factor Receptor Kinase Inhibitors Erlotinib and Gefitinib 
Context
A subset of lung adenocarcinomas appears preferentially sensitive to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs). EGFR-activating mutations and never smoking are associated with response to TKIs.
Objectives
To describe the morphology of adenocarcinomas responsive to TKIs, compare it to tumors in nonresponding patients, and correlate findings with EGFR mutations, gene copy number, and protein expression.
Design
Material from 52 EGFR TKI-treated patients was studied: 29 responders and 23 nonresponders. Adenocarcinoma subtypes and morphologic features were defined in histologic and cytologic material. EGFR mutations were detected by sequencing, copy number by chromogenic in situ hybridization, and expression by immunohistochemistry.
Results
Tumors from TKI responders tended to be better-differentiated adenocarcinomas with bronchioloalveolar carcinoma components. Nonresponders showed more heterogeneous morphology, higher grade, and more subtypes, and were more likely to show solid growth. In nonresponders, the only pure bronchioloalveolar carcinoma was mucinous, a subtype known to be negative for EGFR mutations. Using World Health Organization criteria, all tumors in both groups other than pure bronchioloalveolar carcinomas would be classified as adenocarcinomas, mixed subtype, thereby obscuring some of these distinctions. EGFR mutations were significantly more common in responders (22/29 vs 0/23; P < .001). Immunohistochemistry and chromogenic in situ hybridization results were not significantly correlated with EGFR mutations or response to TKIs in this study.
Conclusions
Overall, histologic differences exist between tumors that respond to TKIs and those that do not, although sampling affects classification, and there is significant histologic overlap between the 2 groups. Response is strongly associated with EGFR mutations.
doi:10.1043/1543-2165-133.3.470
PMCID: PMC4016915  PMID: 19260752
13.  Spectrum of LKB1, EGFR, and KRAS Mutations in Chinese Lung Adenocarcinomas 
Introduction
Somatic LKB1 mutations are found in lung adenocarcinomas at different frequencies in Caucasian and East Asian (Japanese and Korean) populations. This study was designed to characterize the frequency of LKB1 mutations, their relationship to EGFR and KRAS mutations, and their associated clinicopathologic characteristics in Chinese patients.
Methods
Two hundred thirty-nine lung adenocarcinomas consecutively collected from October 2007 to July 2009 were dissected into 3 to 4 small (3 mm) pieces for histopathological analyses of tumor content. Genomic DNA and/or cDNA from 86 samples with more than 70% tumor content were used for sequencing of LKB1 (exons 1–9), EGFR (exons 18–21), and KRAS (exon 2). LKB1 germline mutation status was determined by sequencing of genomic DNA from matched histologically distant lung tissues that are histologically normal.
Results
6.9% of lung adenocarcinomas harbored LKB1 somatic mutations. A total of 10.5% of patients had an LKB1 germline polymorphism, F354L. Interestingly, in two of these patients, tumors displayed loss of heterozygosity at this allele. EGFR kinase domain and KRAS mutations were found in 66.3% and 2.3% of Chinese lung adenocarcinomas, respectively. Concurrent LKB1 and EGFR somatic mutations were observed in one patient. Both KRAS-mutant tumors harbored LKB1 mutations.
Conclusions
These data provide important clinical and molecular characteristics of lung adenocarcinomas from Chinese patients.
doi:10.1097/JTO.0b013e3181e05016
PMCID: PMC4009449  PMID: 20559149
Chinese lung adenocarcinoma; LKB1; EGFR; KRAS; Mutation
15.  Somatic mutations of the Parkinson's disease–associated gene PARK2 in glioblastoma and other human malignancies 
Nature genetics  2009;42(1):77-82.
Mutation of the gene PARK2, which encodes an E3 ubiquitin ligase, is the most common cause of early-onset Parkinson's disease1, 2, 3. In a search for multisite tumor suppressors, we identified PARK2 as a frequently targeted gene on chromosome 6q25.2–q27 in cancer. Here we describe inactivating somatic mutations and frequent intragenic deletions of PARK2 in human malignancies. The PARK2 mutations in cancer occur in the same domains, and sometimes at the same residues, as the germline mutations causing familial Parkinson's disease. Cancer-specific mutations abrogate the growth-suppressive effects of the PARK2 protein. PARK2 mutations in cancer decrease PARK2's E3 ligase activity, compromising its ability to ubiquitinate cyclin E and resulting in mitotic instability. These data strongly point to PARK2 as a tumor suppressor on 6q25.2–q27. Thus, PARK2, a gene that causes neuronal dysfunction when mutated in the germline, may instead contribute to oncogenesis when altered in non-neuronal somatic cells.
doi:10.1038/ng.491
PMCID: PMC4002225  PMID: 19946270
16.  Frequent and Focal FGFR1 Amplification Associates With Therapeutically Tractable FGFR1 Dependency in Squamous-cell Lung Cancer 
Science translational medicine  2010;2(62):62ra93.
Lung cancer remains one of the leading causes for cancer-related death in developed countries. In lung adenocarcinomas, EGFR mutations and EML4-ALK fusions are associated with response to EGFR and ALK inhibition. By contrast, therapeutically exploitable genetic alterations have been lacking in squamous-cell lung cancer. We conducted a systematic search for alterations that are therapeutically amenable and performed high-resolution gene-copy number analyses in a set of 232 lung cancer specimens. We identified frequent and focal FGFR1 amplification in squamous-cell lung cancer (n=155), but not in other lung cancer subtypes, and confirmed its presence in an independent cohort of squamous-cell lung cancer samples employing FISH (22% of cases). Using cell-based screening with the FGFR inhibitor (PD173074) in a large (n=83) panel of lung cancer cell lines, we demonstrated that this compound inhibited growth (p=0.0002) and induced apoptosis (p=0.008) specifically in those lung cancer cells carrying amplified FGFR1. We validated the dependency on FGFR1 of FGFR1-amplified cell lines by knockdown of FGFR1 and by ectopic expression of a resistance allele of FGFR1 (FGFR1V561M), which rescued FGFR1-amplified cells from PD173074-mediated cytotoxicity. Finally we showed that inhibition of FGFR1 with a small molecule led to significant tumor shrinkage in vivo. Focal FGFR1 amplification is common in squamous-cell lung cancer and associated with tumor growth and survival, suggesting that FGFR inhibitors may be a viable therapeutic option in this cohort of patients.
doi:10.1126/scitranslmed.3001451
PMCID: PMC3990281  PMID: 21160078
18.  Analysis of Tumor Specimens at the Time of Acquired Resistance to EGFR TKI therapy in 155 patients with EGFR mutant Lung Cancers 
Purpose
All patients with EGFR mutant lung cancers eventually develop acquired resistance to EGFR tyrosine kinase inhibitors (TKIs). Smaller series have identified various mechanisms of resistance, but systematic evaluation of a large number of patients to definitively establish the frequency of various mechanisms has not been performed.
Experimental Design
Patients with lung adenocarcinomas and acquired resistance to erlotinib or gefitinib enrolled onto a prospective biopsy protocol and underwent a re-biopsy after the development of acquired resistance. Histology was reviewed. Samples underwent genotyping for mutations in EGFR, AKT1, BRAF, ERBB2, KRAS, MEK1, NRAS and PIK3CA, and FISH for MET and HER2.
Results
Adequate tumor samples for molecular analysis were obtained in 155 patients. Ninety-eight had second-site EGFR T790M mutations (63%, 95% CI 55-70%) and four had small cell transformation (3%, 95% CI 0-6%). MET amplification was seen in 4/75 (5%, 95% CI 1-13%). HER2 amplification was seen in 3/24 (13%, 95% CI 3-32%). We did not detect any acquired mutations in PIK3CA, AKT1, BRAF, ERBB2, KRAS, MEK1, or NRAS. (0/88, 0%, 95% CI 0-4%). Overlap among mechanisms of acquired resistance was seen in 4%.
Conclusions
This is the largest series reporting mechanisms of acquired resistance to EGFR TKI therapy. We identified EGFR T790M as the most common mechanism of acquired resistance, while MET amplification, HER2 amplification, and small cell histologic transformation occur less frequently. More comprehensive methods to characterize molecular alterations in this setting are needed to improve our understanding of acquired resistance to EGFR TKIs.
doi:10.1158/1078-0432.CCR-12-2246
PMCID: PMC3630270  PMID: 23470965
EGFR mutant lung cancer; lung adenocarcinoma; targeted therapy; acquired resistance; tyrosine kinase inhibitor therapy
19.  Two co-existing germline mutations P53 V157D and PMS2 R20Q promote tumorigenesis in a familial cancer syndrome 
Cancer letters  2013;342(1):36-42.
Germline mutations are responsible for familial cancer syndromes which account for approximately 5–10% of all types of cancers. These mutations mainly occur at tumor suppressor genes or genome stability genes, such as DNA repair genes. Here we have identified a cancer predisposition family, in which eight members were inflicted with a wide spectrum of cancer including one diagnosed with lung cancer at 22 years old. Sequencing analysis of tumor samples as well as histologically normal specimens identified two germline mutations co-existing in the familial cancer syndrome, the mutation of tumor suppressor gene P53 V157D and mismatch repair gene PMS2 R20Q. We further demonstrate that P53 V157D and/or PMS2 R20Q mutant promotes lung cancer cell proliferation. These two mutants are capable of promoting colony formation in soft agar as well as tumor formation in transgenic drosophila system. Collectively, these data have uncovered the important role of co-existing germline P53 and PMS2 mutations in the familial cancer syndrome development.
doi:10.1016/j.canlet.2013.08.032
PMCID: PMC3981830  PMID: 23981578
P53 V157D; PMS2 R20Q; Germline mutation; Familial cancer syndrome; Co-existing
20.  High dose weekly erlotinib achieves therapeutic concentrations in CSF and is effective in leptomeningeal metastases from epidermal growth factor receptor mutant lung cancer 
Journal of neuro-oncology  2010;99(2):283-286.
Leptomeningeal metastases (LM) occur in 5–10% of patients with solid tumors and are associated with a dismal prognosis. We describe LM from lung adenocarcinoma harboring a mutation in the epidermal growth factor receptor (EGFR) gene that confers sensitivity to the EGFR tyrosine kinase inhibitors (EGFR-TKIs) erlotinib and gefitinib. The CSF concentration of EGFR-TKIs achieved by standard daily dosing may be insufficient for therapeutic effect. However, intermittent (pulsatile) high dose administration (1000–1500 mg/week) achieves a higher CSF concentration than standard dosing, and successfully controlled LM in this patient.
doi:10.1007/s11060-010-0128-6
PMCID: PMC3973736  PMID: 20146086
Leptomeningeal metastases; EGFR; Lung cancer; Erlotinib
21.  Association of KRAS and EGFR Mutations with Survival in Patients with Advanced Lung Adenocarcinomas 
Cancer  2012;119(2):356-362.
Background
Lung adenocarcinomas can be distinguished by identifying mutated driver oncogenes including EGFR and KRAS. Mutations in EGFR are associated with both an improved survival as well as response to treatment with erlotinib and gefitinib. However, the prognostic significance of KRAS has not been evaluated in large numbers of patients and remains controversial. We examined the association of EGFR and KRAS mutations with survival among patients with advanced lung adenocarcinomas.
Methods
We analyzed data from patients with advanced lung adenocarcinomas and known EGFR and KRAS mutation status evaluated between 2002 and 2009. We collected clinical variables including age, gender, Karnofsky Performance Status, smoking history, and treatment history. Overall survival from diagnosis of advanced disease was analyzed using Kaplan-Meier and Cox proportional hazard methods.
Results
We evaluated 1036 patients, including 610 women (59%) and 344 never-smokers (33%). Patients had a median age of 65 (range, 25–92) and the majority (81%) had a KPS ≥80%. In multivariate analysis, EGFR mutations were associated with a longer overall survival (HR= 0.6, p<0.001) and KRAS mutations with a shorter survival (HR=1.21, p=0.048).
Conclusions
KRAS mutations predict shorter survival for patients with advanced lung adenocarcinomas. The presence of EGFR and KRAS mutations define distinct subsets of patients with lung adenocarcinomas, and should be determined in patients upon diagnosis of advanced disease. Clinical trial reports should include EGFR and KRAS mutation status along with other prognostic factors.
doi:10.1002/cncr.27730
PMCID: PMC3966555  PMID: 22810899
non-small cell lung cancer; adenocarcinomas; EGFR; KRAS; survival; prognostic factors
22.  Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitor–Resistant Disease 
Journal of Clinical Oncology  2013;31(8):1070-1080.
Purpose
EGFR-mutant lung cancer was first described as a new clinical entity in 2004. Here, we present an update on new controversies and conclusions regarding the disease.
Methods
This article reviews the clinical implications of EGFR mutations in lung cancer with a focus on epidermal growth factor receptor tyrosine kinase inhibitor resistance.
Results
The discovery of EGFR mutations has altered the ways in which we consider and treat non–small-cell lung cancer (NSCLC). Patients whose metastatic tumors harbor EGFR mutations are expected to live longer than 2 years, more than double the previous survival rates for lung cancer.
Conclusion
The information presented in this review can guide practitioners and help them inform their patients about EGFR mutations and their impact on the treatment of NSCLC. Efforts should now concentrate on making EGFR-mutant lung cancer a chronic rather than fatal disease.
doi:10.1200/JCO.2012.43.3912
PMCID: PMC3589701  PMID: 23401451
23.  Patterns and processes of somatic mutations in nine major cancers 
BMC Medical Genomics  2014;7:11.
Background
Cancer genomes harbor hundreds to thousands of somatic nonsynonymous mutations. DNA damage and deficiency of DNA repair systems are two major forces to cause somatic mutations, marking cancer genomes with specific somatic mutation patterns. Recently, several pan-cancer genome studies revealed more than 20 mutation signatures across multiple cancer types. However, detailed cancer-type specific mutation signatures and their different features within (intra-) and between (inter-) cancer types remain largely unexplored.
Methods
We employed a matrix decomposition algorithm, namely Non-negative Matrix Factorization, to survey the somatic mutations in nine major human cancers, involving a total of ~2100 genomes.
Results
Our results revealed 3-5 independent mutational signatures in each cancer, implying that a range of 3-5 predominant mutational processes likely underlie each cancer genome. Both mutagen exposure (tobacco and sun) and changes in DNA repair systems (APOBEC family, POLE, and MLH1) were found as mutagenesis forces, each of which marks the genome with an evident mutational signature. We studied the features of several signatures and their combinatory patterns within and across cancers. On one hand, we found each signature may influence a cancer genome with different influential magnitudes even in the same cancer type and the signature-specific load reflects intra-cancer heterogeneity (e.g., the smoking-related signature in lung cancer smokers and never smokers). On the other hand, inter-cancer heterogeneity is characterized by combinatory patterns of mutational signatures, where no cancers share the same signature profile, even between two lung cancer subtypes (lung adenocarcinoma and squamous cell lung cancer).
Conclusions
Our work provides a detailed overview of the mutational characteristics in each of nine major cancers and highlights that the mutational signature profile is representative of each cancer.
doi:10.1186/1755-8794-7-11
PMCID: PMC3942057  PMID: 24552141
Somatic mutation; Cancer; Kataegis; Mutation signature; Mutagen; Heterogeneity
24.  Characteristics of Lung Cancers Harboring NRAS Mutations 
Purpose
We sought to determine the frequency and clinical characteristics of patients with lung cancer harboring NRAS mutations. We used preclinical models to identify targeted therapies likely to be of benefit against NRAS mutant lung cancer cells.
Patients and Methods
We reviewed clinical data from patients whose lung cancers were identified at 6 institutions or reported in the Catalogue of Somatic Mutations in Cancer (COSMIC) to harbor NRAS mutations. 6 NRAS mutant cell lines were screened for sensitivity against inhibitors of multiple kinases (i.e. EGFR, ALK, MET, IGF-1R, BRAF, PI3K and MEK).
Results
Among 4562 patients with lung cancers tested, NRAS mutations were present in 30 (0.7%; 95% confidence interval, 0.45% to 0.94%); 28 of these had no other driver mutations. 83% had adenocarcinoma histology with no significant differences in gender. While 95% of patients were former or current smokers, smoking-related G:C>T:A transversions were significantly less frequent in NRAS mutated lung tumors compared to KRAS-mutant NSCLCs (NRAS: 13% (4/30), KRAS: 66% (1772/2733), p<0.00000001). 5 of 6 NRAS mutant cell lines were sensitive to the MEK inhibitors, selumetinib and trametinib, but not to other inhibitors tested.
Conclusion
NRAS mutations define a distinct subset of lung cancers (~1%) with potential sensitivity to MEK inhibitors. While NRAS mutations are more common in current/former smokers, the types of mutations are not those classically associated with smoking.
doi:10.1158/1078-0432.CCR-12-3173
PMCID: PMC3643999  PMID: 23515407
NRAS mutation; EGFR mutation; KRAS mutation; lung cancer; non-small cell lung cancer; driver mutation; MEK inhibitor; erlotinib; gefitinib; crizotinib
25.  Detecting somatic point mutations in cancer genome sequencing data: a comparison of mutation callers 
Genome Medicine  2013;5(10):91.
Background
Driven by high throughput next generation sequencing technologies and the pressing need to decipher cancer genomes, computational approaches for detecting somatic single nucleotide variants (sSNVs) have undergone dramatic improvements during the past 2 years. The recently developed tools typically compare a tumor sample directly with a matched normal sample at each variant locus in order to increase the accuracy of sSNV calling. These programs also address the detection of sSNVs at low allele frequencies, allowing for the study of tumor heterogeneity, cancer subclones, and mutation evolution in cancer development.
Methods
We used whole genome sequencing (Illumina Genome Analyzer IIx platform) of a melanoma sample and matched blood, whole exome sequencing (Illumina HiSeq 2000 platform) of 18 lung tumor-normal pairs and seven lung cancer cell lines to evaluate six tools for sSNV detection: EBCall, JointSNVMix, MuTect, SomaticSniper, Strelka, and VarScan 2, with a focus on MuTect and VarScan 2, two widely used publicly available software tools. Default/suggested parameters were used to run these tools. The missense sSNVs detected in these samples were validated through PCR and direct sequencing of genomic DNA from the samples. We also simulated 10 tumor-normal pairs to explore the ability of these programs to detect low allelic-frequency sSNVs.
Results
Out of the 237 sSNVs successfully validated in our cancer samples, VarScan 2 and MuTect detected the most of any tools (that is, 204 and 192, respectively). MuTect identified 11 more low-coverage validated sSNVs than VarScan 2, but missed 11 more sSNVs with alternate alleles in normal samples than VarScan 2. When examining the false calls of each tool using 169 invalidated sSNVs, we observed >63% false calls detected in the lung cancer cell lines had alternate alleles in normal samples. Additionally, from our simulation data, VarScan 2 identified more sSNVs than other tools, while MuTect characterized most low allelic-fraction sSNVs.
Conclusions
Our study explored the typical false-positive and false-negative detections that arise from the use of sSNV-calling tools. Our results suggest that despite recent progress, these tools have significant room for improvement, especially in the discrimination of low coverage/allelic-frequency sSNVs and sSNVs with alternate alleles in normal samples.
doi:10.1186/gm495
PMCID: PMC3971343  PMID: 24112718

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