Driver Mutations In Lung Adenocarcinoma Research Articles

Obesity-dependent selection of driver mutations in cancer.

Obesity is a risk factor for cancer, but whether obesity is linked to specific genomic subtypes of cancer is unknown. We examined the relationship between obesity and tumor genotype in two clinicogenomic corpora. Obesity was associated with specific driver mutations in lung adenocarcinoma, endometrial carcinoma and cancers of unknown primaries, independent of clinical covariates, demographic factors and genetic ancestry. Obesity is therefore a driver of etiological heterogeneity in some cancers.

Analysis of actionable genetic alterations in lung carcinoma from the VA National Precision Oncology Program

Lung cancer is the leading cause of cancer mortality in men and women. Genomic sequencing of non-small cell lung cancer (NSCLC) is critical for the optimal treatment of NSCLC. In this study we sought to describe the frequencies of highly actionable driver mutations in lung adenocarcinoma (LUAD), squamous cell (LUSQ) and other NSCLC histologies (LUOT) in Veterans tested through the VA's National Precision Oncology Program (NPOP) and compare these frequencies to other published datasets from highly specialized academic cancer centers. The NPOP cohort included 3,376 unique Veterans with a diagnosis of lung carcinoma tested between February 2019 and January 2021 including 1892 with LUAD, 940 with LUSQ, and 549 with LUOT. Among patients with LUAD, 27.5% had highly actionable genetic variants. The frequency of targetable mutations was as follows: ALK rearrangement 0.8%, BRAF V600E 2.1%, EGFR exon 20 insertion mutation 0.48%, EGFR sensitizing mutations 6.6%, ERBB2 small variants 1.2%, KRAS G12C 14.0%, MET exon 14 skipping mutation 1.5%, NTRK rearrangement 0.1%, RET rearrangement 0.4%, and ROS1 rearrangement 0.3%. The frequency of EGFR mutations, RET rearrangement, MET exon 14 and ERBB2 small variants frequencies were significantly lower in NPOP compared to other published reports while MET amplification was more common in NPOP. Combined rates of highly actionable genetic variants were 2.7% and 13.4% in LUSQ and LUOT, respectively. In this study, 27.5% of Veterans with lung adenocarcinoma have actionable genetic alterations eligible for FDA approved targeted therapies, a frequency only slightly lower than other published datasets despite higher smoking rates in Veterans. Genomic sequencing should be performed in all Veterans with advanced LUAD and LUOT.

MA11.02 Targeting HER2 Exon 20–Mutant Lung Adenocarcinoma with a Novel Tyrosine Kinase Inhibitor, Mobocertinib

Although pharmacologic agents targeting driver mutations in lung adenocarcinoma have led to tremendous clinical benefits for patients, human epidermal growth factor receptor 2 (HER2)-activating mutations do not have therapeutic agents and still represent an unmet clinical need. Mobocertinib is a potent tyrosine kinase inhibitor designed to target epidermal growth factor receptor (EGFR) and HER2 exon 20 insertion mutations and has reported activity in the clinic in patients with EGFR exon 20 insertionmutant non–small cell lung cancer (NSCLC).

Survival and prognostic factors in surgically treated brain metastases.

While surgery and radiation remain the mainstays of therapy for all patients with brain metastases (BM), the management is moving to a more individualized approach based on the underlying tumor. We sought to identify prognostic factors of both intracranial progression (IC-PFS) and overall survival (OS) in a surgical cohort. We retrospectively reviewed the records of 1015 patients treated surgically for BM at Brigham and Women's Hospital (2007-2017). Kaplan-Meier curves were used for OS and IC-PFS and Cox proportional hazards models were built to assess for predictive factors. Common origins were lung (43.9%), breast (14.4%), and melanoma (13.8%). Median OS for the cohort was 15.4months (95% confidence interval [95%CI] 14.1-17.1). Breast cancer (22.1months, 95%CI 17.8-30.3) and colorectal cancer (10.6months, 95%CI 7.2-15.4) had the longest and shortest OS, respectively. On multivariable Cox regression, significant prognostic factors of shorter OS were age (HR 1.01, 95%CI 1.01-1.02), number of lesions (HR 1.56, 95%CI 1.28-1.89), extracranial spread at BM diagnosis (HR 1.26, 95%CI 1.05-1.52), and KPS (HR 0.98, 95%CI 0.98-0.99). Regarding molecular factors, all driver mutations in lung adenocarcinoma had a favorable effect (EGFR, HR 0.53, 95%CI 0.31-0.89; ALK, HR 0.28, 95%CI 0.12-0.66; KRAS, HR 0.65, 95%CI 0.47-0.92), triple negative status predicted poor prognosis in breast adenocarcinoma (HR 2.04, 95%CI 1.13-3.69), while no effect of BRAF/NRAS mutations was demonstrated in melanoma BMs. Our results corroborate the role of tumor origin and systemic as well as intracranial spread in OS. Heterogeneity within histologies was further explained by molecular alterations.

Yield of Malignant Pleural Effusion for Detection of Oncogenic Driver Mutations in Lung Adenocarcinoma

Pleural fluid can be used to assess targetable mutations in patients with lung adenocarcinoma. The primary objective of this study was to assess the yield of pleural fluid cytology for targetable oncogenic mutations (EGFR, KRAS, BRAF, ALK, and ROS1 gene rearrangements). We also assessed pleural fluid volume necessary for molecular testing. Retrospective review was performed of 134 consecutive patients with lung adenocarcinoma associated malignant pleural effusions. EGFR and KRAS testing was done using PCR amplification followed by DNA sequencing, or next generation sequencing in more recent cases that included BRAF assessment. Fluorescence in situ hybridization employing break-apart probes was used to test for ALK and ROS1 rearrangements. Mutation analysis on pleural fluid cell-block was performed on 56 patients. It was adequate for complete analysis ordered including EGFR, KRAS, BRAF, ALK, and ROS1 rearrangements on 40 (71.4%) samples. For individual mutations, EGFR testing was possible in 38 of 49 (77.6%); KRAS 22 of 28 (78.6%); BRAF 10 of 13 (76.9%), ALK gene rearrangement 42 of 51 (82.4%) and ROS1 gene rearrangement in 21 of 28 (75%) pleural fluid specimens. The analysis was satisfactory in 13 of 19 (68.4%) samples with ≤100 mL versus 27 of 37 (72.9%) with >100 mL of fluid tested (P-value=0.7). Genetic mutation analysis can be performed on malignant pleural effusions secondary to lung adenocarcinoma, independent of fluid volume.

Epidermal growth factor receptor (EGFR), KRAS, and BRAF mutations in lung adenocarcinomas: A study from India

Mitogen-Activated Protein (MAP) Kinase pathway involves several oncogenic genes which can serve as potential targets for therapy. Therefore, aim of the present study is to analyze mutations in the MAP Kinase pathway in pulmonary adenocarcinoma (ADCA) of Indian patients along with clinico-pathologic correlation and determination of the survival status in patients receiving therapy. Blocks and slides of 125 pulmonary ADCA of last 5 years were retrieved. Histo-morphology and tumor content were determined. EGFR, KRAS, BRAF and MEK1 genes were analyzed using Sanger sequencing and Real-time polymerase chain reaction (PCR). Clinico-pathologic correlation and survival analysis were performed. Fifty-eight (46.4%) patients harbored genetic mutations of which 49 had single somatic mutations, 5 had multiple exonic and 4 showed coexisting EGFR and KRAS mutations. EGFR mutations were seen in 24.8%, KRAS in 19.2% and BRAF (non-V600E) in 2.4% cases. There was no difference in progression-free survival of wild- type/single mutations when compared with multiple/ coexisting mutations (P = 0.09). However, the P value may indicate borderline correlation. To conclude, EGFR and KRAS mutations may coexist in the same patient in lung ADCA. Multiple exonic mutations of KRAS gene formed substantial percentage of our cohort, requiring further exploration. Lung ADCA harbouring BRAF mutations are commonly non-V600E. Testing of all major genetic driver mutations of lung ADCA irrespective of histology and other demographic characteristics is necessary.

Driver mutations of young lung adenocarcinoma patients with malignant pleural effusion.

Young lung cancer patients have several distinct characteristics. However, there are limited epidemiological data of genetic abnormalities in this population. We conducted a prospective cohort study to delineate the various oncogenic driver mutations of lung adenocarcinoma in young Asian patients. We consecutively collected malignant pleural effusions (MPEs) from lung adenocarcinoma patients. RNA was extracted from MPEs for mutation analysis by reverse transcription-polymerase chain reaction and direct sequencing. Selected gene mutations for testing included EGFR, HER2, BRAF, KRAS, PIK3CA, JAK2, MEK1, NRAS, and AKT2 mutations, as well as EML4-ALK, ROS1, and RET fusions. We collected MPEs from 142 patients aged ≤50 years and 730 patients aged >50 years. Patients aged ≤50 years (91%) had a higher incidence of driver gene mutations than those aged >50 years (84%; P = .036), especially EML4-ALK (P < .001) and ROS1 (P < .001). Among patients aged ≤50 years, EGFR mutation was the major oncogenic driver mutation. The mutation rates of other genes were 18% EML4-ALK, 6% ROS1, 5% HER2, 1% RET, 1% BRAF, and 1% KRAS. We did not detect PIK3CA, JAK2, MEK1, NRAS, or AKT2 mutations. No difference in gender or smoking history was noted among those with different driver mutations. Patients who had a good performance status or received appropriate targeted therapy had longer overall survival. In conclusion, lung adenocarcinoma in Asian patients aged ≤50 years had a higher gene mutation rate than in those aged >50 years, especially EML4-ALK and ROS1 fusion. Mutation analysis may be helpful in determining targeted therapy for the majority of these patients.

Lung non-terminal respiratory unit type adenocarcinoma: a clinicopathologic study

Objective: To evaluate the clinicopathologic characteristics of lung non-terminal respiratory unit (non-TRU) type adenocarcinoma. Methods: Seventy-two cases of lung non-TRU type adenocarcinoma that underwent complete resection and diagnosed at Departments of Pathology, Affiliated Suzhou Hospital of Nanjing Medical University and Nanjing General Hospital of the PLA from January 2005 to December 2016 were retrospectively studied. The histomorphological changes and precursor lesions were observed under microscope. The expression of lineage-specific markers and tumor stem cell markers was detected by immunohistochemistry (IHC). The major driver mutations of lung adenocarcinoma were tested by ARMS and directive gene sequencing. Results: Non-TRU type adenocarcinomas were more commonly found in male (65.3%, 47/72), former or current smokers (68.1%, 49/72), the elder (mean 61 years old), central adenocarcinoma (75.0%, 54/72), tumors with necrosis (61.1%, 44/72) and higher grade (73.6%, 53/72). Histologically, non-TRU type adenocarcinoma displayed complex histomorphology and was often composed of large irregular gland-like and acinar pattern accumulating extracellular mucin, necrotic tumor cell debris and neutrophils, or invasive adenocarcinoma with mucin production. The tumor cells were composed of bronchial surface epithelial cells, mucinous column cells, polygonal cells and goblet cells. Eighteen (25.0%), 23 (31.9%) and 28 (38.9%) cases exhibited ciliated columnar cell metaplasia (CCCM), mucous columnar cell change (MCCC) and bronchiolar columnar cell dysplasia (BCCD) (precursor lesion of lung adenocarcinoma). IHC showed the expression of CK7 (100.0%, 72/72), TTF1 (12.5%, 9/72), Napsin A (5.6%, 4/72), MUC5AC (81.9%, 59/72), MUC5B (87.5%, 63/72), p53 (66.7%, 48/72), CK5/6 (12.5%, 9/72), p63 (18.1%, 13/72), CK20 (19.4%, 14/72) and CDX2 (16.7%, 12/72) in the tumor cells. The expression of tumor stem cell markers was detected in 43.1% cases (31/72) for CD44, 31.9% (23/72) for CD133, 58.3% (42/72) for β-catenin, 36.1% (26/72) for ALDH1, 12.5% (9/72) for GATA6, 20.8% (15/72) for SOX2 and 29.2% (21/72) for OCT4. The driver mutations were 26.4% (19/72) for KRAS, 2.8% (2/72) for EGFR and 1.4% (1/72) for EML4-ALK, and none for BRAF and ROS1. Conclusion: Non-TRU type adenocarcinoma is an uncommon subtype of lung adenocarcinoma with distinct clinicopathologic characteristics, histologic appearances, immunophenotype and molecular genetic alterations.

Common driver mutations and smoking history affect tumor mutation burden in lung adenocarcinoma

BackgroundRecent progress in genomic analysis using next-generation sequencing technology has enabled the comprehensive detection of mutations and tumor mutation burden (TMB) in patients. A high TMB (TMB-H) tumor is defined as one with high somatic mutational rates, which correlates with clinical responses to certain treatments such as immunotherapies. We determined TMB in lung adenocarcinoma and clarified the characteristics of patients with TMB-H in relation to common driver mutations and smoking history. Materials and methodsGenomic aberrations and TMB were determined in Japanese patients with lung adenocarcinoma (n = 100) using next-generation sequencing of 415 known cancer genes. TMB-H was defined as > 20 mutations per megabase (Mb) of sequenced DNA. ResultsThe median TMB was 13.5 (5-33) mutations/Mb. Ten of 100 (10%) patients showed TMB-H, and the others showed low TMB (TMB-L). Only two of 10 (20%) patients with TMB-H had one of the common driver mutations (ALK and ERBB2 mutation), whereas 57 of 90 (63%) patients with TMB-L had one of the driver mutations, including ALK, EGFR, ERBB2, ROS, RET, and MET (P < 0.05). Notably, no EGFR mutation was observed in patients with TMB-H. Eight of 10 (80%) patients with TMB-H had recent smoking history, whereas only 17 of 90 (19%) patients with TMB-L had recent smoking history (P < 0.001). ConclusionsWe found that TMB-H is associated with smoking history, whereas TMB-L is associated with the common driver mutations in lung adenocarcinoma, which may impact treatment strategies for these patients.

Pathologic subtype-defined prognosis is dependent on both tumor stage and status of oncogenic driver mutations in lung adenocarcinoma.

Previous studies have shown that the prognosis of lung adenocarcinoma is associated with pathological characterization. In this study, we investigated whether pathology-based prognosis was further influenced by both tumor stage and oncogenic driver mutations. To this end, we recruited a cohort of 465 lung adenocarcinoma patients in China. These patients were classified into 6 pathology-defined subtypes i.e., lepidic-predominant adenocarcinoma (LPA), acinar-predominant adenocarcinoma (APA), papillary-predominant adenocarcinoma (PPA), micropapillary-predominant adenocarcinoma (MPA), solid-predominant adenocarcinoma (SPA), and invasive mucinous adenocarcinoma (IMA). Oncogenic mutations in EGFR, KRAS, ALK, RET, and BRAF genes were determined using fluorescent real-time RT-PCR. The associations of pathogenic subtype or oncogenic mutation with clinical characteristics were analyzed using Fisher’s exact tests. The interactive effects on overall survival (OS) by pathologic subtype, oncogenic mutations, and tumor stage were also determined. We have found that pathogenic subtype of lung adenocarcinoma correlated with smoking habit and tumor cell differentiation. These pathology-defined subtypes can be regrouped into 3 pathology-based prognostic groups: PPG1 (LPA), PPG2 (IMA+APA+PPA), and PPG3 (MPA+SPA) with a favorable, intermediate, and poor OS, respectively. We further demonstrated that this pathology-determined OS can be affected by both tumor stage and status of oncogenic mutations in EGFR, KRAS, ALK, RET, and BRAF genes. Interestingly, the presence of genetic mutations related to ALK, RET and BRAF had an opposite effect on OS between PPG2 (worsen) and PPG3 (improved) patients, reversing the prognostic favorability for patients within these two groups. In conclusion, prognosis of lung adenocarcinoma was defined interactively by pathologic subtype, tumor stage and oncogenic mutation.

HER2 Transmembrane Domain (TMD) Mutations (V659/G660) That Stabilize Homo- and Heterodimerization Are Rare Oncogenic Drivers in Lung Adenocarcinoma That Respond to Afatinib

IntroductionErb-b2 receptor tyrosine kinase (HER2) transmembrane domain (TMD) mutations (HER2V659E, HER2G660D) have previously been identified in lung adenocarcinomas, but their frequency and clinical significance is unknown. MethodsWe prospectively analyzed 8551 consecutive lung adenocarcinomas using hybrid capture–based comprehensive genomic profiling (CGP) at the request of the individual treating physicians for the purpose of making therapy decisions. ResultsWe identified 15 cases (0.18%) of HER2 TMD mutations (HER2V659E/D, HER2G660D) through CGP of 8551 lung adenocarcinomas. HER2 TMD mutations were mutually exclusive from HER2 kinase domain mutations and other oncogenic drivers in lung adenocarcinoma. Only two cases with HER2 TMD mutations (13%) had concurrent Erb-b2 receptor tyrosine kinase 2 gene (HER2) amplification. Structural analysis of HER2 TMD association revealed that mutations at positions V659 and G660 to the highly polar residues glutamic acid, aspartic acid, or arginine should stabilize homodimerization and heterodimerization of HER2 in the active conformation. Treatment with afatinib, a pan-HER inhibitor, resulted in durable clinical response in three of four patients with lung adenocarcinoma, with two harboring HER2V659E and one with double HER2V659E/G660R mutations. HER2 TMD mutations (V659 and G660) are found in other non-NSCLC malignancies, and analogous TMD mutations are also found in EGFR, HER3, and HER4. ConclusionHER2 TMD mutations represent rare but distinct targetable driver mutations in lung adenocarcinoma. CGP capable of detecting diverse HER2 alterations, including HER2 TMD mutations, should be broadly adopted to identify all patients who may benefit from HER2-targeted therapies.

P114: Intratumor heterogeneity of driver mutations in lung adenocarcinoma

Background Lung cancers are characterized by the genetic alterations that often affect a common group of oncogenic signaling pathways. Identification of biologically significant genetic alterations in lung cancer that lead to activation of oncogenes and inactivation of tumor suppressor genes has the potential to provide further therapeutic opportunities (Cooper, 2013). In this context, it is important that molecular aberrations may act as negative predictors of sensitivity to treatment. The discovery of driver oncogenes, such as activating mutations in the epidermal growth factor receptor gene (EGFR), has made personalized medicine for lung cancer a reality. Despite the high initial results, NSCLC patients acquire resistance to tyrosine kinase inhibitors in the worldwide. There are several findings suggesting that the effect of tyrosine kinase inhibitors could be limited to patients harboring KRAS mutation. To date, a limited information regarding link of morphological portrait of adenocarcinomas with bearing of simultaneously concurrent mutations of KRAS and EGFR genes. The detection of concurrent gene mutation is usually carried out in a mixture of tumor cells. We plan to analyze EGFR and KRAS mutations in all clonal components (or morphological structures) of NSCLC tumors isolated by laser microdissection. So, we suggest that NSCLC clonal components might bear two concurrent EGFR and KRAS mutations simultaneously or different clonal components might bear either EGFR or KRAS mutations. The data obtained can predict resistance to EGFR-TKIs and affect therapeutic decision making. Materials and methods The tumor samples were obtained from archived formalin-fixed paraffin-embedded tissue blocks. Paraffin was removed by xylene extraction, and the sample was subsequently lysed by proteinase K. The region containing the highest percentage of tumor cells (at least 50%) was dissected. Microscopes Axio Scope A1 and Axio Star plus (Carl Zeiss, Germany) was used to perform histological analysis. If necessary, tumour cells were carefully selected and removed from the samples by laser microdissection using a P.A.L.M. microlaser instrument (PALM AdhesiveCaps, P.A.L.M., Bernried, Germany). EGFR (exon 19 deletion and 21 L858R) and KRAS (Gly12Cys, Gly12Ser, Gly12Arg, Gly12Val, Gly12Asp, Gly12Ala, Gly13Asp) gene amplification was based on RT-PCR on CFX96 Real-Time System (Bio-Rad). Results A total of 115 patients with stage (IIIB–IV) of NSCLC with EGFR-TKI- sensitive mutations were eligible for the analysis. A rare coexistence of KRAS and EGFR mutations were observed in 3 patients (2.6%). The first sample was described as nonmucinous solid adenocarcinoma and has deletion of 19 exon of EGFR gene and G12C mutation of KRAS gene. The second sample was described as mucinous lepidic adenocarcinoma and has deletion of 19 exon of EGFR gene and G12D mutation of KRAS gene. The third sample was described as mucinous adenocarcinoma with solid and acinar monoclonal components and also has deletion of 19 exon of EGFR gene and G12C mutation of KRAS gene. Of all the samples, only one had two different monoclonal components. Unfortunately, this sample was not available due to biopsy and few numbers of cells for microdissection. Fiala et al. (2013) reported that KRAS mutations were not only as a negative prognostic factor and also as a biomarker predicting resistance to EGFR-TKIs, especially G12C. Patient with nonmucinous solid adenocarcinoma with deletion of 19 exon and G12C (EGFR and KRAS genes, respectively) is unlikely to benefit from receiving gefitinib or erlotinib. Conclusion The data obtained show that further studies are required to improve personalized therapy for NSCLC patients. The frequency and type of KRAS and EGFR mutations were first assessed in NSCLC patients from West Siberia. This work was supported by a Grant from the OPTEK Company (No 122/2014/51/Nvs ).

Are We Making Progress in Lung Cancer Using Progression-Free Survival as a Surrogate End Point?

Non–small-cell lung cancer (NSCLC) is the secondmost common cancer diagnosed in the United States and the leading cause of cancer-related mortality, with an estimated 221 200 newcases and 158 040deaths anticipated in2015.1Despite advances in treatment, 5-year survival remains lowat 16.8% across all patients, and only 2% in patients with stage 4 disease, indicating a need for novel therapies that affect survival. The identification of driver mutations in lung adenocarcinoma has dramatically changed the therapeutic landscape and improved treatment options for patients with advanced-stage disease, specifically, targeted options for patients with tumors that harbor mutations in the epidermal growth factor receptor (EGFR) gene or rearrangement in the anaplastic lymphoma kinase (ALK) gene. Whereas some targetedagentshavebeenapprovedon thebasisofdata fromrandomized phase 3 trials, theALK inhibitors crizotinib and ceritinibwere grantedpreliminary approval by theFoodandDrug Administration on the basis of early phase 1 data2,3; efficacy of crizotinibwas latervalidated in randomizedphase3 trials.4,5 In this issueof JAMAOncology, Lakdawallaandcolleagues6 discuss the incremental social value of providing early access to newNSCLC treatment on the basis of progression-free survival (PFS) alone. Their analysis finds that early access based on any PFS benefit produces an overall loss of greater than $170 000pernewly treatedpatient permonth,whereas granting access to drugs with PFS benefit between 1 and 3 months is more cost-effective. They also note that PFS benefit correlates with overall survival (OS) benefit in 71% of studies. Thisanalysis raises importantquestions regardingdrugapproval and treatment decisionmodels in the context of inherently limitedhealth care resources. Particularlywith regard to NSCLC, the analysis further raises questions of how to evaluate cost-benefit in the era of targeted therapy. In the Food and Drug Administration’s new drug approvalprocess, cost considerationsare taboo;approval isbased strictly on a thorough assessment of whether the protocolspecified primary end point wasmet, and PFS is increasingly common as a primary end point. At the same time, everincreasing costs of health care have long been the focus of nationwide attention and attempts at reform, begging the question, should such reform give greater weight to incremental social valueof access to treatment?Furthermore, givennet social value as a consideration, which parameters should be included in the value calculation? In the analysis presented by Lakdawalla and colleagues,6 indirect cost of treatment is considered, although not comprehensively; a more accurate picture may require a model with more detailed adjustment for net changes in overall treatment-related costs, such as differences inadverseevents,need for additional clinicvisits orhospitalizations due to therapy, and family member burden. Amore sophisticatedmodel, to consider treatment crossover as well as more detailed consideration of indirect costs, may be particularly important in the era of targeted therapy, given that (1) when purchase price alone is considered, tarRelated article page 196 Research Original Investigation Modeling Access DecisionsWith Surrogate End Points

Abstract LB-100: Discovery of HM61713 as an orally available and mutant EGFR selective inhibitor

Abstract Introduction: Activating mutations of EGFR are well known as oncogenic driver mutations in lung adenocarcinoma. Currently, EGFR TKIs including Gefitinib and Erlotinib are used as the first line therapy in NSCLC patients harboring EGFR activating mutations. However, drug resistance caused by T790M mutation limits the efficacy of these 1st generation EGFR TKIs. Currently, some of the next generation EGFR TKIs are under investigation for the treatment of lung cancer patients having T790M mutation. In our current presentation, to obtain HM61713, an EGFR mutant selective inhibitor, as a clinical candidate and the evaluation of HM61713 for mutant EGFR cancer model will be introduced. Method: Novel analogues were designed and synthesized to find active compounds for the T790M mutation as well as EGFR activating mutations with good selectivity over wild- type EGFR. Finally, HM61713 was selected as a clinical candidate through multi-optimization processes including both in vitro and in vivo pharmacologcal studies. Results: HM61713 was designed as an irreversible kinase inhibitor having a Michael acceptor, which covalently binds to a cysteine residue near the kinase domain of mutant the EGFR. In a cell wash out test, HM61713 inhibited phospho-EGFR for a long duration with a half-life of over 24 hours. From in vitro study, HM61713 showed potent activities for H1975 (L858-T790M) and HCC827 (exon 19 del.) with GI50 values of 9.2 nM and 10 nM, respectively. Instead, it showed low potency for H358 (wild type EGFR NSCLC) with GI50 of 2,225 nM. In xenograft studies using H1975 and HCC827, HM61713 resulted in good efficacy without showing any side effects. Conclusion: HM61713 showed excellent in vitro and in vivo activities for H1975 harboring L858R-T790M mutation as well as HCC827 having exon 19 deletion mutation with selectivity over wild-type EGFR. Currently, HM61713 is undergoing phase I study (NCT01588145) for NSCLC patients after the failure of 1st generation EGFR TKIs in Korea. Citation Format: Kwang-Ok Lee, Mi Young Cha, Mira Kim, Ji Yeon Song, Jae-Ho Lee, Young Hoon Kim, Young-Mi Lee, Kwee Hyun Suh, Jeewoong Son. Discovery of HM61713 as an orally available and mutant EGFR selective inhibitor. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr LB-100. doi:10.1158/1538-7445.AM2014-LB-100

Prognostic value analysis of mutational and clinicopathological factors in non-small cell lung cancer.

IntroductionTargeting activating oncogenic driver mutations in lung adenocarcinoma has led to prolonged survival in patients harboring these specific genetic alterations. The prognostic value of these mutations has not yet been elucidated. The prevalence of recently uncovered non-coding somatic mutation in promoter region of TERT gene is also to be validated in lung cancer. The purpose of this study is to show the prevalence, association with clinicalpathological features and prognostic value of these factors.MethodsIn a cohort of patients with non-small cell lung cancer (NSCLC) (n = 174, including 107 lung adenocarcinoma and 67 lung squamous cell carcinoma), EGFR, KRAS, HER2 and BRAF were directly sequenced in lung adeoncarcinoma, ALK fusions were screened using FISH (Fluorescence in situ Hybridization).TERT promoter region was sequenced in all of the 174 NSCLC samples. Associations of these somatic mutations and clinicopathological features, as well as prognostic factors were evaluated.Results EGFR, KRAS, HER2, BRAF mutation and ALK fusion were mutated in 25.2%, 6.5%, 1.9%, 0.9% and 3.7% of lung adenocarcinomas. No TERT promoter mutation was validated by reverse-sided sequencing. Lung adenocarcinoma with EGFR and KRAS mutations showed no significant difference in Disease-free Survival (DFS) and Overall Survival (OS). Cox Multi-variate analysis revealed that only N stage and HER2 mutation were independent predictors of worse overall survival (HR = 1.653, 95% CI 1.219–2.241, P = 0.001; HR = 12.344, 95% CI 2.615–58.275, P = 0.002).ConclusionsWe have further confirmed that TERT promoter mutation may only exist in a very small fraction of NSCLCs. These results indicate that dividing lung adenocarcinoma into molecular subtypes according to oncogenic driver mutations doesn't predict survival difference of the disease.

Protein expression of programmed death 1 ligand 1 and ligand 2 independently predict poor prognosis in surgically resected lung adenocarcinoma.

BackgroundThe clinicopathologic characteristics of tumors expressing programmed death (PD-1) ligands (PD-Ls) PD-L1 or PD-L2 and their associations with common driver mutations in lung adenocarcinoma are not clearly defined, despite the progression of anti-PD-1/PD-L1 immunotherapy.MethodsPD-L1 and PD-L2 expression was measured by immunohistochemistry in 143 surgically resected lung adenocarcinomas and was correlated with clinical variables, histologic subtypes, and the mutational status of EGFR, KRAS, HER2, and ALK.ResultsPositive PD-L1 expression was significantly associated with more advanced T status, N status, and pathologic stage. Histologically, lung adenocarcinomas with positive PD-L1 staining were less likely to be adenocarcinoma in situ or minimally invasive adenocarcinoma and more likely to have solid predominant subtype. Both PD-L1 expression (odds ratio =1.984, 95% confidence interval =1.010–3.894; P=0.047) and PD-L2 expression (odds ratio =2.328, 95% confidence interval =1.201–4.512; P=0.012) were independent predictors of poor overall survival. When the combined PD-L expression and pathologic stage were used together to predict overall survival, the concordance index increased to 0.763, and the Akaike information criteria value decreased to 356.08.ConclusionWe defined the clinicopathologic features of lung adenocarcinomas with high expression of PD-L1 and PD-L2. We further demonstrated the role of PD-L expression as a useful prognostic marker for lung adenocarcinoma.

Abstract PR02: Recurrent oncogenic mutations in the small GTPase RIT1 activate PI3K and MEK.

Abstract Recently, we identified somatic mutations in the RAS-family small GTPase gene RIT1 in 2.4% (10/413) of lung adenocarcinoma tumors. Mutation of RIT1 is mutually exclusive with other oncogenic mutations in the receptor tyrosine kinase/RAS pathway, suggesting that RIT1 mutations are rare driver mutations in lung adenocarcinoma. Oncogenic RIT1 mutations cluster in the switch II domain of the protein and are observed not only in lung adenocarcinoma but also in myeloid malignancies, breast carcinoma, cervical carcinoma, and in the germline of Noonan syndrome patients. Here we functionally characterize 26 RIT1 point mutations and in-frame insertions/deletions in murine fibroblasts and human immortalized lung epithelial cells and find that the majority of somatic RIT1 mutations are able to transform cells. Furthermore, we identified a human lung cancer cell line, NCI-H2110, with an endogenous RIT1 p.M90I mutation. Knockdown of RIT1 in NCI-H2110 cells revealed the role of RIT1 in regulation of PI3K and MEK signaling. Consistently, combination PI3K/MEK inhibition could inhibit cellular transformation induced by ectopic expression of mutated RIT1. Furthermore, PI3K inhibition suppressed in vivo growth of NCI-H2110 cells. These data identify RIT1 as an oncogene and nominate combined PI3K and MEK inhibition as a therapeutic strategy in RIT1-mutated cancers. This abstract is also presented as Poster A04. Citation Format: Alice H. Berger, Fujiko Duke, Marcin Imielinski, Nathan Kaplan, Jeremiah Wala, Geng-Xian Shi, Douglas A. Andres, Matthew Meyerson. Recurrent oncogenic mutations in the small GTPase RIT1 activate PI3K and MEK. [abstract]. In: Proceedings of the AACR-IASLC Joint Conference on Molecular Origins of Lung Cancer; 2014 Jan 6-9; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2014;20(2Suppl):Abstract nr PR02.

Molecular Typing of Lung Adenocarcinoma on Cytological Samples Using a Multigene Next Generation Sequencing Panel

Identification of driver mutations in lung adenocarcinoma has led to development of targeted agents that are already approved for clinical use or are in clinical trials. Therefore, the number of biomarkers that will be needed to assess is expected to rapidly increase. This calls for the implementation of methods probing the mutational status of multiple genes for inoperable cases, for which limited cytological or bioptic material is available. Cytology specimens from 38 lung adenocarcinomas were subjected to the simultaneous assessment of 504 mutational hotspots of 22 lung cancer-associated genes using 10 nanograms of DNA and Ion Torrent PGM next-generation sequencing. Thirty-six cases were successfully sequenced (95%). In 24/36 cases (67%) at least one mutated gene was observed, including EGFR, KRAS, PIK3CA, BRAF, TP53, PTEN, MET, SMAD4, FGFR3, STK11, MAP2K1. EGFR and KRAS mutations, respectively found in 6/36 (16%) and 10/36 (28%) cases, were mutually exclusive. Nine samples (25%) showed concurrent alterations in different genes. The next-generation sequencing test used is superior to current standard methodologies, as it interrogates multiple genes and requires limited amounts of DNA. Its applicability to routine cytology samples might allow a significant increase in the fraction of lung cancer patients eligible for personalized therapy.

Personalized Treatment of Lung Adenocarcinoma

Non–small cell lung cancer, most often known as adenocarcinoma, is notoriously fatal and less chemosensitive than many other solid and hematologic malignancies. Nonetheless, recent advances in the understanding of molecular cancer biology have allowed translational application of targeted agents in lung adenocarcinoma that work specifically on key proteins derived from common driver oncogenes. Notably, tyrosine kinase inhibitors (TKIs) against epidermal growth factor receptor (EGFR), anaplastic lymphoma kinase (ALK), and c-ros oncogene 1 receptor tyrosine kinase (ROS1) have received much clinical attention over the past few years. The treatment paradigm for advanced lung adenocarcinoma has subsequently changed markedly. Instead of treating all lung adenocarcinomas alike, it is now routine to determine the tumor’s genetic profile, specifically EGFR mutations, ALK rearrangement, and possibly ROS1 rearrangement, to achieve a customized treatment plan. There is now ample evidence to support the role of EGFR TKI as a first-line treatment of advanced EGFR-mutated lung adenocarcinoma, with an anticipated similar role for ALK TKI in ALK-rearranged tumor. A growing list of potentially targetable driver mutations in lung adenocarcinoma has also emerged, making personalized therapy in lung adenocarcinoma a possibility.

How and when to use genetic markers for nonsmall cell lung cancer

Many driver mutations that determine the malignant behavior of lung cancer have been identified in recent years. The promise of therapies targeted to the specific molecular pathways altered by such mutations has made genetic testing in nonsmall cell lung cancer (NSCLC) attractive to clinicians. We reviewed recent research on clinically relevant genetic and molecular tests for patients with NSCLC, with an emphasis on the tests linked to actionable mutations that influence therapy and improve outcomes. Mutations in the epidermal growth factor receptor gene (EGFR) and translocations involving the anaplastic lymphoma kinase (ALK) gene have been shown to be common driver mutations in lung adenocarcinoma. The presence or absence of these mutations has been demonstrated to predict response to targeted therapy in many recent studies. Targeted therapies for patients with mutations in the EGFR domain or the echinoderm microtubule-associated protein-like 4 anaplastic lymphoma kinase translocation have been shown to be effective and are approved for use. Ongoing studies continue to define the extent of their utility and may continue to expand their indications. Sufficient tissue for genetic analysis can be obtained from cytologic samples, including those obtained from endobronchial ultrasound-guided transbronchial needle aspiration. Genetic testing for driver mutations is useful in identifying patients with NSCLC who are likely to respond to targeted therapy. These tests are best used in patients with adenocarcinoma who have advanced-stage cancer.