Combination of EGFR-TKI and Chemotherapy Versus EGFR-TKI Monotherapy as Neoadjuvant Treatment of Stage III-N2 EGFR-Mutant Non-Small Cell Lung Cancer.

BACKGROUND: The efficacy of neoadjuvant treatment with epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) monotherapy in patients with stage III-N2 EGFR-mutant remains unsatisfactory. This study explored the potential benefits of combining first-generation EGFR-TKI with chemotherapy as a neoadjuvant treatment for patients with stage III-N2 EGFR-mutant non-small cell lung cancer (NSCLC). PATIENTS AND METHODS: The medical records of patients with III-N2 EGFR-mutant NSCLC who received neoadjuvant therapy with EGFR-TKI at Shanghai Chest Hospital from October 2011 to October 2022 were retrospectively reviewed. Patients with stage III-N2 EGFR-mutant NSCLC who received first-generation TKI combined with chemotherapy as neoadjuvant treatment were included in the combination group, and those who received EGFR-TKI monotherapy were included in the monotherapy group. The study assessed the objective response rate (ORR) according to Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1, disease-free survival (DFS), overall survival (OS), downstaging rates of pathologic lymph nodes (from stage N2 to N1 or N0), major pathologic response (MPR) rate, pathological complete response (PCR) rate, and safety. RESULTS: A total of 74 631 patients with EGFR-mutant NSCLC were screened, and 60 patients were included, 7 of whom did not undergo surgery after neoadjuvant targeted therapy. Of the remaining 53 patients, 15 received first-generation EGFR-TKI combined with chemotherapy as neoadjuvant treatment, and 38 received EGFR-TKI monotherapy. The median follow-up time was 44.12 months. The ORR was 50.0% (9/18) in the combination group and 40.5% (17/42) in the monotherapy group (P = .495). The MPR rate was 20.0% (3/15) and 10.5% (4/38) in the combination and monotherapy groups, respectively (P = .359). No patients achieved PCR in the combination group, while 3 (7.89%) attained PCR in the monotherapy group. The 2 groups did not differ in N2 downstaging rate (P = .459). The median DFS was not reached in the combination group, while it was 23.6 months (95% CI: 8.16-39.02) in the monotherapy group (P = .832). Adverse events observed were consistent with those commonly associated with the 2 treatments. CONCLUSION: Combination therapy with first-generation EGFR-TKI and chemotherapy could be considered a neoadjuvant treatment option for patients with stage III-N2 EGFR-mutant NSCLC, exhibiting acceptable toxicity. However, regarding short-term efficacy, combination therapy did not demonstrate superiority over EGFR-TKI monotherapy. Long-term follow-up is warranted for a more accurate assessment of the DFS and OS.

Genetic mutation profiling reveals biomarkers for targeted therapy efficacy and prognosis in non-small cell lung cancer.

Introduction: The genetic heterogeneity of non-small cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) mutations may affect clinical responses and outcomes to EGFR tyrosine kinase inhibitors (EGFR-TKIs). This study aims to investigate the genomic factors that influence the efficacy and clinical outcomes of first-line, second-line and third-line treatments in NSCLC and explore the heterogeneity of resistance mechanisms. Materials and methods: This real-world study comprised 65 patients with EGFR mutant NSCLC. Molecular alterations were detected using a customized DNA panel before and after administering targeted therapy. The efficacy and prognosis of each treatment line were evaluated. Results: In first-generation EGFR-TKIs treatment, gefitinib showed favorable efficacy compared to icotinib and erlotinib, particularly in patients with EGFR L858R mutations. The resistance mechanisms to first-generation EGFR-TKIs varied among different EGFR mutation cohorts and different first-generation EGFR-TKIs. In second-line EGFR-TKIs treatment, EPH receptor A3 (EPHA3), IKAROS family zinc finger 1 (IKZF1), p21 (RAC1) activated kinase 5 (PAK5), DNA polymerase epsilon, catalytic subunit (POLE), RAD21 cohesin complex component (RAD21) and RNA binding motif protein 10 (RBM10) mutations were markedly associated with poorer progression-free survival (PFS). Notably, EPHA3, IKZF1 and RBM10 were identified as independent predictors of PFS. The mechanisms of osimertinib resistance exhibited heterogeneity, with a higher proportion of non-EGFR-dependent resistant mutations. In third-line treatments, the combination of osimertinib and anlotinib demonstrated superior efficacy compared to other regimens. Glutamate ionotropic receptor NMDA type subunit 2A (GRIN2A) mutation was an independent risk indicator of shorter OS following third-line treatments. Conclusions: Comprehending the tumor evolution in NSCLC is advantageous for assessing the efficacy and prognosis at each stage of treatment, providing valuable insights to guide personalized treatment decisions for patients.

Genetic alterations predict poor efficacy, outcomes and resistance to second-line osimertinib treatment in non-small cell lung cancer.

The genetic heterogeneity of non-small cell lung cancer (NSCLC) may impact clinical response and outcomes to targeted therapies. In second-line osimertinib treatment for NSCLC, real-world data on genetic biomarkers for treatment efficacy and prognosis remain incomplete. This real-world study involved 68 NSCLC patients receiving first-generation epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs). All of these patients developed resistance, and 49 of them subsequently underwent second-line osimertinib treatment. A 639-gene DNA panel was employed to assess the impact of molecular alterations on treatment efficacy, clinical outcomes and resistance. The findings showed that the median progression-free survival (PFS) for second-line osimertinib therapy was 13.3 months. Genes alterations such as P21 (RAC1) activated kinase 5 (PAK5), RNA binding motif protein 10 (RBM10), and EPH receptor A3 (EPHA3) mutations were associated with significantly shorter PFS in osimertinib therapy. At multivariate analysis, they were all independent risk predictors of shorter PFS. Additionally, the median overall survival (OS) for osimertinib was 26.2 months. Glutamate ionotropic receptor NMDA type subunit 2A (GRIN2A), hepatocyte growth factor (HGF), and RBM10 mutations were significantly associated with poorer OS in osimertinib treatment. The multivariate analysis demonstrated that only RBM10 mutation emerged as an independent risk predictor of shorter OS. In vitro experiments showed that RBM10 mutations could promote the proliferation and migration ability of NSCLC cells and reduced cell apoptosis. The resistance mechanisms to osimertinib were heterogeneous. Histone cluster 1 H2B family member D (HIST1H2BD) acted as a novel resistance mechanism to osimertinib. Previously unreported HIST1H2BD mutations (p.K25Q and p.E36D) were detected in the NSCLC tissues. In vitro experiments confirmed that HIST1H2BD mutations led to resistance to osimertinib. In summary, we demonstrate that genetic biomarkers, such as PAK5, RBM10, and EPHA3, are independent predictors of PFS in second-line osimertinib treatment, with RBM10 emerging as an independent predictor of OS. Additionally, HIST1H2BD represents a novel resistance mutation to osimertinib. All of these findings offer valuable insights for making personalized treatment strategies for NSCLC patients.

PD-L1 expression and its correlation with clinicopathological and molecular characteristics in Chinese patients with non-small cell lung cancer.

Little is known about the relationship between programmed cell death-ligand 1 (PD-L1) expression and histologic and genetic features in real-world Chinese non-small cell lung cancer patients. From November 2017 to June 2019, tumor tissues were collected from 2674 non-small cell lung cancer patients. PD-L1 expression was detected with immunohistochemistry using the 22C3 and SP263 antibodies, and patients were stratified into subgroups based on a tumor proportion score of 1%, 1% to 49%, and ≥ 50%. Genetic alterations were profiled using targeted next-generation sequencing. In the total population, 50.5% had negative PD-L1 expression (tumor proportion score < 1%), 32.0% had low-positive expression (1%-49%), and 17.5% had high-positive expression (≥50%). The PD-L1 positive rate was 39.0% in squamous cell carcinomas and 53.6% in adenocarcinomas. PD-L1 expression was higher in squamous cell carcinomas (P < .001) and lower in adenocarcinomas (P < .001). Of the overall patient population, 11.2% had Kirsten rat sarcoma viral oncogene (KRAS) mutations, 44.9% had epidermal growth factor receptor (EGFR) mutations, 2.1% had BRAF V600E mutations, 0.3% had MET exon 14 skipping mutations, 5.4% had anaplastic lymphoma kinase translocations, and 0.9% had ROS proto-oncogene 1 translocations. Patients carrying ROS proto-oncogene 1 translocations (P = .006), KRAS (P < .001), and MET (P = .023) mutations had significantly elevated expression of PD-L1, while those harboring EGFR (P < .001) mutations had lower PD-L1 expression. In our study, PD-L1 expression was significantly higher in squamous cell carcinomas and lower in adenocarcinomas, and was positively associated with MET and KRAS mutations, as well as the wild-type EGFR gene state. Nonetheless, additional studies are needed to further validate those associations and determine the clinical significance for immune checkpoint inhibitors of these factors.

Rationale and design of a multicenter, randomized phase II trial of durvalumab with or without multitarget tyrosine kinase inhibitor as maintenance treatment in extensive-stage small-cell lung cancer patients (DURABLE study).

INTRODUCTION: Durvalumab is a check-point inhibitor against programmed death ligand-1 (PD-L1), and anlotinib is a new orally administered multitarget tyrosine kinase inhibitor (TKI). Both agents have been approved in China. Preclinical and clinical trials have suggested that antiangiogenic therapy has the potential to alleviate immunosuppression and showed synergetic effect when combined with ICIs. However, it is unclear that whether this combination is effective when initiated as maintenance treatment in ES-SCLC patients. METHODS: This is a multicenter, randomized, phase II study. A total of 64 eligible patients who do not experience disease progression after four cycles platinum-based chemotherapy combined with durvalumab will be randomized to durvalumab with anlotinib or durvalumab alone until disease progression, withdrawal of consent, or unacceptable toxicity. The primary endpoint is PFS (from randomization); secondary endpoint was OS and PFS (from diagnosis), objective response rate (ORR); disease control rate (DCR) and duration of response (DOR), safety and tolerability assessed by the National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE) version 5.0. DISCUSSION: We conduct a phase II study to investigate the safety and efficacy of durvalumab combined with anlotinib as maintenance treatment in ES-SCLC patients.

A randomized double-blind trial of TQB2450 with or without anlotinib in pretreated driver-negative non-small cell lung cancer.

OBJECTIVE: Immune monotherapy as second-line treatment confers only modest survival benefit on non-small cell lung cancer (NSCLC) patients with no mutated driver genes, necessitating combination treatment strategies. This phase Ib trial investigated the efficacy and safety of anti-PD-L1 antibody TQB2450 plus antiangiogenic drug anlotinib for NSCLC. MATERIALS AND METHODS: Pretreated stage IIIB or IV NSCLC patients with wild-type EGFR/ALK and minimally one measurable lesion were randomized 1:1:1 to receive TQB2450 1200 mg plus placebo, or TQB2450 1200 mg plus anlotinib 10 or 12 mg. The primary outcome was progression-free survival (PFS) and the secondary outcomes included objective response rate (ORR). RESULTS: Thirty-three patients received TQB2450 plus placebo and 34 patients each received TQB2450 plus anlotinib 10 mg and 12 mg. At the data cutoff, the median PFS was 8.7 months (95% CI 6.1-17.1) in the TQB2450 plus anlotinib group and 2.8 months (95% CI 1.4-4.7) in the TQB2450 only group. The ORR reached 30.9% (95% CI 20.2%-43.3%) in the TQB2450 plus anlotinib group and was 3.0% (95% CI 0.1%-15.8%) in the TQB2450 only group. In patients with PD-L1 ≥ 1%, the ORR was 50.0% (95% CI 33.4%-66.6%) for TQB2450 plus anlotinib and 5.3% (95% CI 0.1%-26.0%) for TQB2450 plus placebo. No new safety signals were observed. CONCLUSION: Anlotinib plus TQB2450 demonstrated promising antitumor activities in advanced NSCLC patients without EGFR and ALK alterations and the toxicities were overall manageable. The study findings support the continued development of TQB2450 plus anlotinib for advanced NSCLC patients without driver gene alterations.

Joint analysis of phenotype-effect-generation identifies loci associated with grain quality traits in rice hybrids.

Genetic improvement of grain quality is more challenging in hybrid rice than in inbred rice due to additional nonadditive effects such as dominance. Here, we describe a pipeline developed for joint analysis of phenotypes, effects, and generations (JPEG). As a demonstration, we analyze 12 grain quality traits of 113 inbred lines (male parents), five tester lines (female parents), and 565 (113×5) of their hybrids. We sequence the parents for single nucleotide polymorphisms calling and infer the genotypes of the hybrids. Genome-wide association studies with JPEG identify 128 loci associated with at least one of the 12 traits, including 44, 97, and 13 loci with additive effects, dominant effects, and both additive and dominant effects, respectively. These loci together explain more than 30% of the genetic variation in hybrid performance for each of the traits. The JEPG statistical pipeline can help to identify superior crosses for breeding rice hybrids with improved grain quality.

DT-PICS: An Efficient and Cost-Effective SNP Selection Method for the Germplasm Identification of Arabidopsis.

Germplasm identification is essential for plant breeding and conservation. In this study, we developed a new method, DT-PICS, for efficient and cost-effective SNP selection in germplasm identification. The method, based on the decision tree concept, could efficiently select the most informative SNPs for germplasm identification by recursively partitioning the dataset based on their overall high PIC values, instead of considering individual SNP features. This method reduces redundancy in SNP selection and enhances the efficiency and automation of the selection process. DT-PICS demonstrated significant advantages in both the training and testing datasets and exhibited good performance on independent prediction, which validates its effectiveness. Thirteen simplified SNP sets were extracted from 749,636 SNPs in 1135 Arabidopsis varieties resequencing datasets, including a total of 769 DT-PICS SNPs, with an average of 59 SNPs per set. Each simplified SNP set could distinguish between the 1135 Arabidopsis varieties. Simulations demonstrated that using a combination of two simplified SNP sets for identification can effectively increase the fault tolerance in independent validation. In the testing dataset, two potentially mislabeled varieties (ICE169 and Star-8) were identified. For 68 same-named varieties, the identification process achieved 94.97% accuracy and only 30 shared markers on average; for 12 different-named varieties, the germplasm to be tested could be effectively distinguished from 1,134 other varieties while grouping extremely similar varieties (Col-0) together, reflecting their actual genetic relatedness. The results suggest that the DT-PICS provides an efficient and accurate approach to SNP selection in germplasm identification and management, offering strong support for future plant breeding and conservation efforts.

Efficacy and safety of first-line anlotinib-based combinations for advanced non-small cell lung cancer: a three-armed prospective study.

Background: The evidence of combined therapies of multi-target agents in first-line treatment of advanced non-small cell lung cancer (NSCLC) was limited. This study aimed to evaluate the safety and efficacy of anlotinib combined with epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI), chemotherapy, or immune checkpoint inhibitor (ICI) in advanced NSCLC. Methods: This open-label, three-arm, prospective study (NCT03628521) enrolled untreated locally advanced/metastatic NSCLC patients. Patients with EGFR mutation NSCLC received anlotinib and erlotinib (cohort A). Patients without EGFR/ALK/ROS1 mutation received anlotinib combined with carboplatin plus pemetrexed/gemcitabine (cohort B), or sintilimab (cohort C). The primary outcomes were safety and objective response rate (ORR). The secondary endpoints included progression-free survival (PFS), disease control rate (DCR), and overall survival (OS). Treatments were performed for at least 2 cycles and efficacy was evaluated every 2 cycles using RECIST version 1.1. Safety was assessed throughout the study. Results: A total of 30, 30, and 22 patients were enrolled in cohorts A, B, and C, respectively. There were 3 patients did not complete the treatment in cohort A. In cohorts A and B, ≥ grade 3 treatment-related adverse events (TRAEs) occurred in 77.3% and 60.0% of patients, respectively. The most common TRAEs were rash (10.0%) and decreased platelet count (30.0%) in cohorts A and B, respectively. The ORRs were 92.9% and 60.0% in cohorts A and B, respectively, and DCRs were 96.4% and 96.7%, respectively. The ORR and incidence of ≥ grade 3 TRAEs of cohort C were, which 72.7% and 54.5%, which had been published previously. Median PFSs [95% confidence interval (CI)] were 21.6 (15.6 to 24.9), 13.0 [10.5 to not estimated (NE)], and 15.6 (12.9 to NE) months in cohorts A, B, and C, respectively. Median OS was 28.1 (95% CI: 21.82 to NE) months in cohort B. The 24-month OS rates in cohorts A and C were 87.1% and 83.9%, respectively. Conclusions: Anlotinib-based combinations with EGFR-TKI, chemotherapy, and ICI are well-tolerated and encouraging as first-line therapies for advanced NSCLC, which could be verified in future studies. Anlotinib-based combination might provide multiple choices for first-line treatment in patients with advanced NSCLC.

Afatinib 30 mg in the treatment of common and uncommon EGFR-mutated advanced lung adenocarcinomas: a retrospective, single-center, longitudinal study.

Background: Afatinib 30 mg has been proved to be with comparable efficacy but more tolerable than the dose of 40 mg for Asian patients with non-small cell lung cancer (NSCLC). This study aimed to investigate the clinical outcomes of afatinib at 30 mg/d in the treatment of advanced lung adenocarcinomas (LAD) with common and uncommon epidermal growth factor receptor (EGFR) mutations. Methods: EGFR-mutated advanced LAD patients receiving afatinib (30 mg/d) from January 2017 to November 2021 were retrospectively included. EGFR status was classified into three subtypes, namely common mutations including exon 19 deletions (19del) and exon 21 L858R (21L858R), uncommon mutations including G719X, L861Q, S768I, and complex mutations, and separately exon 20 insertions (20ins). Progression-free survival (PFS), objective response rate (ORR), disease control rate (DCR) and adverse events (AEs) were analyzed during regular follow-up. Results: The overall median PFS of totally 58 included patients was 9.83 [95% confidence index (CI): 5.76-13.91] months. The number of patients with common, uncommon, and 20ins mutations was 32 (55.2%), 19 (32.8%) and 7 (12.1%), respectively. Baseline characteristics did not differ significantly among the three subtypes. The corresponding median PFS was 13.97 (12.06-15.89), 8.48 (0.32-16.64), and 3.78 (1.93-5.64) months, respectively (P=0.002). In the first-line setting, patients with common and uncommon mutations had a significantly longer PFS compared to those with 20ins [14.53 (13.53-15.53) vs. 10.39 (4.87-15.91) vs. 2.37 (0.00-5.11) months, P<0.001]. The first-line ORR showed significant differences among the three subtypes (60% vs. 80% vs. 0.0%, P=0.023). All-grade AEs occurred in 22 patients (37.9%). AEs ≥ grade 3 mainly included diarrhea (8.6%), and none of the patients discontinued treatment due to severe AEs. Conclusions: Afatinib at 30 mg/d is associated with a favorable efficacy and tolerability in the treatment of advanced LAD with common and major uncommon EGFR mutations except 20ins. Further large-scale prospective studies are warranted to confirm our findings.

mTOR pathway gene mutations predict response to immune checkpoint inhibitors in multiple cancers.

BACKGROUND: mTOR pathway is known to promote cancer malignancy and influence cancer immunity but is unknown for its role in immune checkpoint inhibitors (ICI) therapy. METHODS: Using Memorial Sloan-Kettering Cancer Center dataset (MSKCC), we extracted mTOR pathway gene mutations for stepwise Cox regression in 1661 cancer patients received ICI. We associated the mutation of the gene signature resulted from the stepwise Cox regression with the 1661 patients' survival. Other 553 ICI-treated patients were collected from 6 cohorts for validation. We also performed this survival association in patients without ICI treatment from MSKCC as discovery (n = 2244) and The Cancer Genome Atlas (TCGA) as validation (n = 763). Pathway enrichment analysis were performed using transcriptome profiles from TCGA and IMvigor210 trial to investigate the potential mechanism. RESULTS: We identified 8 genes involved in mTOR pathway, including FGFR2, PIK3C3, FGFR4, FGFR1, FGF3, AKT1, mTOR, and RPTOR, resulted from stepwise Cox regression in discovery (n = 1661). In both discovery (n = 1661) and validation (n = 553), the mutation of the 8-gene signature was associated with better survival of the patients treated with ICI, which was independent of tumor mutation burden (TMB) and mainly attributed to the missense mutations. This survival association was not observed in patients without ICI therapy. Intriguingly, the mutation of the 8-gene signature was associated with increased TMB and PD1/PD-L1 expression. Immunologically, pathways involved in anti-tumor immune response were enriched in presence of this mutational signature in mTOR pathway, leading to increased infiltration of immune effector cells (e.g., CD8 + T cells, NK cells, and M1 macrophages), but decreased infiltration of immune inhibitory M2 macrophages. CONCLUSIONS: These results suggested that mTOR pathway gene mutations were predictive of better survival upon ICI treatment in multiple cancers, likely by its association with enhanced anti-tumor immunity. Larger studies are warranted to validate our findings.

Rationale and design of a phase II trial of dacomitinib in advanced non-small cell lung cancer patients with uncommon epidermal growth factor receptor mutations: a prospective and single arm study (DANCE study).

BACKGROUND: Dacomitinib is a second-generation, irreversible epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI). ARCHER-1050 showed that this agent can improve progression-free survival and overall survival in advanced non-small cell lung cancer patients with sensitive EGFR mutation compared to gefitinib. However, it is unclear whether dacomitinib is effective in patients with sensitizing uncommon EGFR mutations in exon 18-21. The aim of this study is to investigate the safety and efficacy of dacomitinib in these patients. METHODS: This is a single arm, prospective, open label and phase II trial. Sample size will be calculated by a minimax two-stage design method based on the following parameters: α = 0.075, 1-ß = 0.9, P0 = 0.20, P1 = 0.45 and a dropout rate of 10%. A total of 30 eligible patients will be included. Patients will receive continuous oral therapy with dacomitinib (45 mg/day) until disease progression, withdrawal of consent, or unacceptable toxicity, whichever occurs first. The primary endpoint is objective response rate (ORR) per RECIST version 1.1, as assessed by investigators' review. The second endpoint is disease control rate (DCR), PFS, OS, and safety. DISCUSSION: We conduct a single arm, phase II study to investigate the safety and efficacy of dacomitinib in advanced NSCLC patients with sensitizing uncommon EGFR mutations. The results of the DANCE study will provide new data regarding efficacy and safety of these patients. TRIAL REGISTRATION: NCT04504071.

Identification and Validation of Noncanonical RET Fusions in Non-Small-Cell Lung Cancer through DNA and RNA Sequencing.

RET fusion has emerged as a targetable driver in non-small-cell lung cancer. A comparative analysis on RET fusions at DNA [DNA sequencing (DNA-seq)] and RNA [RNA sequencing (RNA-seq)] levels was performed in this study. Archived tumor samples from 54 non-small-cell lung cancer patients with DNA-level noncanonical RET fusions were selected for RNA-seq. RNA-seq identified RET fusion transcripts in 41 of 44 samples passing quality control. In the subset of cases harboring RET 3'-end fusions and predicted to produce in-frame proteins (group A; n = 33), RNA-seq identified the same 3'-end fusions in 32 (96.9%). A total of 26 of 32 also had a reciprocal RET 5'-end fusion detected by DNA-seq that was not transcribed. In the subset with DNA-level out-of-frame RET fusions (group B; n = 9), RNA-seq identified in-frame RET fusion transcripts in 8 cases (88.9%). In the subset only identified with a RET 5'-end fusion by DNA-seq (group C; n = 2), RNA-seq detected the corresponding 3'-end fusion in one case. The discordant DNA- and RNA-level fusions observed in group B may be mediated by complex genomic rearrangement events and transcriptional or post-transcriptional processes. In conclusion, DNA-seq demonstrates a high concordance of 96.9% on detecting in-frame RET fusion, but shows a low concordance on detecting out-of-frame RET fusion and RET 5'-end fusion compared with RNA-seq.

Effective identification of varieties by nucleotide polymorphisms and its application for essentially derived variety identification in rice.

BACKGROUND: Plant variety identification is the one most important of agricultural systems. Development of DNA marker profiles of released varieties to compare with candidate variety or future variety is required. However, strictly speaking, scientists did not use most existing variety identification techniques for "identification" but for "distinction of a limited number of cultivars," of which generalization ability always not be well estimated. Because many varieties have similar genetic backgrounds, even some essentially derived varieties (EDVs) are involved, which brings difficulties for identification and breeding progress. A fast, accurate variety identification method, which also has good performance on EDV determination, needs to be developed. RESULTS: In this study, with the strategy of "Divide and Conquer," a variety identification method Conditional Random Selection (CRS) method based on SNP of the whole genome of 3024 rice varieties was developed and be applied in essentially derived variety (EDV) identification of rice. CRS is a fast, efficient, and automated variety identification method. Meanwhile, in practical, with the optimal threshold of identity score searched in this study, the set of SNP (including 390 SNPs) showed optimal performance on EDV and non-EDV identification in two independent testing datasets. CONCLUSION: This approach first selected a minimal set of SNPs to discriminate non-EDVs in the 3000 Rice Genome Project, then united several simplified SNP sets to improve its generalization ability for EDV and non-EDV identification in testing datasets. The results suggested that the CRS method outperformed traditional feature selection methods. Furthermore, it provides a new way to screen out core SNP loci from the whole genome for DNA fingerprinting of crop varieties and be useful for crop breeding.

EGFR Thr790Leu as a Potential Resistance Mechanism to First-Generation EGFR Tyrosine Kinase Inhibitor May Respond to Osimertinib in Patients With Lung Adenocarcinoma.

INTRODUCTION: It has been well established that EGFR Thr790Met is one of the major resistance mechanisms to first- and second-generation EGFR tyrosine kinase inhibitors (TKIs). Nevertheless, whether EGFR Thr790Leu (T790L), which shares the mutation site of Thr790 with EGFR Thr790Met, mediates resistance to EGFR TKIs remains elusive. The treatment options for patients harboring this rare mutation have not been reported. METHODS: Capture-based targeted ultradeep sequencing was performed on tumor and plasma samples collected at various treatment milestones from three patients with advanced lung adenocarcinoma undergoing targeted therapy. RESULTS: Needle biopsy of lymph node metastasis from patient 1 revealed EGFR T790L at disease progression on first-line treatment of gefitinib. Patient 2 had EGFR T790L identified from needle biopsy of lung tissue at disease progression on icotinib treatment. This patient was subsequently treated with osimertinib and achieved stable disease with a progression-free survival of 9 months. For patient 3, at disease recurrence after surgery, resected lung tumor tissue was retrieved for molecular profiling and revealed EGFR exon 19 deletion and EGFR T790L. The patient subsequently received osimertinib treatment and continued to benefit for 16 months and counting. She has maintained stable disease at the time of submission of this manuscript. CONCLUSIONS: We revealed for the first time that EGFR T790L may serve as a potential resistance mechanism to first-generation EGFR TKIs. We also report the first clinical evidence of efficacy generated by osimertinib in patients with lung adenocarcinoma harboring primary or acquired EGFR T790L, shedding light on treatment options for this subset of patients.

Novel ETV1 mutation in small cell lung cancer transformation resistant to EGFR tyrosine kinase inhibitors.

BACKGROUND: Non-small cell lung cancer (NSCLC) patients harboring mutations in the epidermal growth factor receptor (EGFR) gene respond dramatically to EGFR tyrosine kinase inhibitors (TKIs). However, these patients inevitably develop acquired resistance to EGFR-TKIs. Among them, small cell lung cancer (SCLC) transformation is a relatively rare mechanism. METHODS: We used a 639 cancer-relevant gene panel to detect genetic differences in tissues before and after EGFR-TKIs resistance caused by SCLC transformation. In vitro experiments were conducted to study the role of ETS variant transcription factor 1 (ETV1) on SCLC transformation and EGFR-TKIs resistance. RESULTS: We present two EGFR-mutant lung adenocarcinoma (LUAD) patients. One patient, with EGFR exon 19 deletion (Ex19del), accepted first-line gefitinib treatment and then received osimertinib treatment due to acquisition of an EGFR-T790M mutation. A novel ETV1 mutation (p.P159S) was detected in the SCLC tissue after osimertinib resistance when not coexisting with T790M. The other patient harbored an EGFR exon 21 mutation (p.L858R), and had a long-lasting response to first-line gefitinib, and then transformed to SCLC after TKI resistance. A previously unreported ETV1 mutation (p.E462Q) was detected in the SCLC tissue. In vitro, ETV1 p.E462Q and p.P159S mutations participated in neuroendocrine differentiation by inducing the expression of achaete-scute homolog 1 (ASCL1) and promoting the proliferation of H69 cells. ETV1 p.E462Q and p.P159S mutations were also resistant to gefitinib and osimertinib after introduction into H358 cells. CONCLUSIONS: Novel ETV1 p.E462Q and p.P159S mutations were found in the SCLC tissues of TKIs-resistant LUAD patients, providing a new understanding of ETV1 involvement in acquired resistance to EGFR-TKIs via SCLC transformation.

Next-generation sequencing of tissue and circulating tumor DNA: Resistance mechanisms to EGFR targeted therapy in a cohort of patients with advanced non-small cell lung cancer.

BACKGROUND: Epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) has been considered as an effective treatment in epidermal growth factor receptor-mutant (EGFR-mutant) advanced non-small cell lung cancer (NSCLC). However, most patients develop acquired resistance eventually. Here, we compared and analyzed the genetic alterations between tissue assay and circulating tumor DNA (ctDNA) and further explored the resistance mechanisms after EGFR-TKI treatment. METHODS AND MATERIALS: Amplification refractory mutation system-polymerase chain reaction (ARMS-PCR), Cobas® ARMS-PCR and next-generation sequencing (NGS) were performed on tissue samples after pathological diagnosis. Digital droplet PCR (ddPCR) and NGS were performed on plasma samples. The association between genetic alterations and clinical outcomes was analyzed retrospectively. RESULTS: Thirty-seven patients were included. The success rate of re-biopsy was 91.89% (34/37). The total detection rate of EGFR T790M was 62.16% (23/37) and the consistency between tissue and ctDNA was 78.26% (18/23). Thirty-four patients were analyzed retrospectively. For tissue re-biopsy, 24 patients harbored concomitant mutations. Moreover, tissue re-biopsy at resistance showed 21 patients (21/34, 61.76%) had the concomitant somatic mutation. The three most frequent concomitant mutations were TP53 (18/34, 52.94%), MET (4/34, 11.76%), and PIK3CA (4/34, 11.76%). Meanwhile, 21 patients (21/34, 61.76%) with EGFR T790M mutation. Progression-free survival (PFS) and overall survival (OS) were better in patients with T790M mutation (p = 0.010 and p = 0.017) or third-generation EGFR-TKI treatment (p < 0.0001 and p = 0.073). Interestingly, concomitant genetic alterations were significantly associated with a worse prognosis for patients with EGFR T790M mutation receiving third-generation EGFR-TKIs (p = 0.037). CONCLUSIONS: Multi-platforms are feasible and highly consistent for re-biopsy after EGFR-TKI resistance. Concomitant genetic alterations may be associated with a poor prognosis for patients with EGFR T790M mutation after third-generation EGFR-TKIs.

Feasibility of Surgical Resection After Induction Epidermal Growth Factor Receptor-Tyrosine Kinase Inhibitor Therapy for N2 Lung Adenocarcinomas.

BACKGROUND: Prognosis of patients with stage IIIA-N2 lung adenocarcinoma is still not optimistic. The aim of this study was to evaluate safety, feasibility, and outcomes of surgery after induction epidermal growth factor receptor-tyrosine kinase inhibitor therapy in a clinical trial setting. METHODS: Fourteen patients with IIIA-N2 lung adenocarcinoma and epidermal growth factor receptor mutation received erlotinib induction followed by surgery in a phase II clinical trial. Perioperative outcomes and survival results were compared with a control group of 15 patients receiving neoadjuvant chemotherapy during the same time period. RESULTS: Thirteen patients showed partial response to induction, whereas 16 patients remained stable. Serum carcinoembryonic antigen level in the erlotinib group was significantly higher than in the chemotherapy group before treatment but was reduced to similar levels after induction. Operation time, blood loss, resection extents, complete resection rates, postoperative drainage, complication rates, and length of hospital stay were all comparable between the 2 groups. Thoracoscopic resection was accomplished in 78.6% of patients in the erlotinib group and 80.0% of patients in the chemotherapy group (P = .924) but was higher in patients who responded to induction than those who did not (92.3% vs 68.8%, P = .119). A resection extent greater than lobectomy and incomplete resections were only seen in stable disease after induction. No significant difference was detected in 1-year and 3-year overall or disease-free survivals between the 2 groups. CONCLUSIONS: Pulmonary resection is safe and feasible after induction treatment with erlotinib for stage IIIA-N2 lung adenocarcinomas. Better surgical and oncologic outcomes may be expected in patients who respond to effective induction therapies.

Analysis of the clinical effect of osimertinib on 90 cases with advanced lung adenocarcinoma.

BACKGROUND: Primary or secondary drug resistance of epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKI) is a new challenge in the treatment of advanced non-small cell lung cancer (NSCLC). Osimertinib is a third-generation EGFR-TKI, and its efficacy and safety in NSCLC patients with first-generation EGFR-TKI resistance, especially lung adenocarcinoma, are not yet clear. The purpose of this study was to observe the efficacy and adverse reactions of osimertinib in the treatment of patients with advanced lung adenocarcinoma. METHODS: From January 2017 to December 2018, 90 patients with advanced (stage IV) lung adenocarcinoma were diagnosed in Shanghai Chest Hospital. The disease of these patients (94.4%) progressed after first-line EGFR-TKI treatment, and 43.3% of patients received third-line or beyond third-line treatment. The efficacy and adverse reactions of osimertinib treatment were observed. RESULTS: Among 90 patients with advanced lung adenocarcinoma, 57 (63.3%) achieved partial response (PR), 27 (30.0%) had stable disease (SD), and 6 (6.7%) had progressive disease (PD). The objective response rate (ORR) was 63.3%, and the disease control rate (DCR) was 93.3%. The median progression-free time (mPFS) was 10.41 months (95% CI: 8.91-11.91 months), and the median overall survival (mOS) was 31.37 months (95% CI: 26.37-36.37 months). The incidence of adverse events of degree 3 and above was 7.78%. The main adverse events were diarrhea (28.9%) and rash (24.4%). After symptomatic treatment, the incidence of adverse events was significantly reduced. CONCLUSIONS: Osimertinib has a definite curative effect in the treatment of patients with advanced lung adenocarcinoma, and the incidence of adverse reactions is low.

Efficacy of erlotinib as neoadjuvant regimen in EGFR-mutant locally advanced non-small cell lung cancer patients.

BACKGROUND: The optimal neoadjuvant regimen for locally advanced resectable non-small cell lung cancer (NSCLC) remains controversial. EGFR inhibitors have significantly improved survival in patients with EGFR-mutant advanced NSCLC. However, their efficacy in neoadjuvant settings, particularly for treating locally advanced NSCLC, remains unclear. We compared the clinical benefits of chemotherapy and erlotinib as neoadjuvant therapy for stage IIIA NSCLC. METHOD: Thirty-one treatment-naïve Chinese patients with stage IIIA NSCLC were enrolled. Patients without EGFR mutation received cisplatin-based doublet chemotherapy (n = 16; N-chemo group) while EGFR-mutant patients received erlotinib (n = 15; N-TKI group) as neoadjuvant therapy. RESULTS: After completing neoadjuvant treatment, 12 and 8 patients from the N-TKI and N-chemo groups underwent surgery, respectively. Our data revealed that patients who received erlotinib had a marginally better clinical objective response rate (67% vs. 19%), pathological response rate (67% vs. 38%), and overall survival (51.0 months vs. 20.9 months) compared with those who received chemotherapy. Furthermore, patients in the N-TKI group had a significantly greater reduction in tumor diameter, serum carcinoembryonic level, and maximum allelic fraction. CONCLUSION: Our findings demonstrate that erlotinib is an effective neoadjuvant regimen in patients with EGFR-mutant locally advanced NSCLC, paving the way for its extended use in neoadjuvant settings.[ClinicalTrials.gov identifier: NCT01217619].