Chinese Non-small Cell Lung Cancer Research Articles

Abstract 5838: The landscape of EGFR exon 20 insertion mutations in Chinese patients with non-small cell lung cancer

Abstract Background: The epidermal growth factor receptor (EGFR) is one of the most commonly altered genes in non-small cell lung cancer(NSCLC). Of these, insertion mutation in 20 exon (Ex20ins) of the EGFR occurs less frequently. In comparison with the common EGFR mutations (19Del/L858R), the NSCLC patients with Ex20ins have a worse prognosis. Recently, the FDA approved targeted oral therapeutic agent for NSCLC patients with EX20ins mutation, which has markedly improved their survival. Here we carry out a complete analysis of the frequency and types of EGFR 20 Exon insertion mutations in the large-scale NSCLC cohort of the Chinese population. Methods: From January 2020 to October 2021, a total of 4,091 patients were confirmed as NSCLC were included in the study. The Next-generation sequencing was utilized for detecting genetic mutations. Results: Among the 4,091 NSCLC patients, 2,411 (58.9%) experienced EGFR mutations. In which we identified 90 patients(2.2%) with Ex20ins. All of the Ex20ins were localized between amino acids S767-V774, and after C-helix of the EGFR kinase domain. Different from the exon 19 deletion, we found that Ex20ins exhibits various types of mutations. A total of 34 Ex20ins types were detected, with the most common A767_V769dupASV and S768_D770dupSVD mutations, accounting for 26% and 22.2% respectively. In addition, H773dupH (6.67%), H773_V774dupHV(5.56%), H773_V774insAH (2.22%), D770_N771insG (2.22%), and N771_P772insG(2.22%) were also observed in the NSCLC patients. Conclusions: We described the landscape of EGFR Ex20ins in Chinese NSCLC patients cohort. Based on the large sample size, the frequency of the Ex20ins mutation in Chinese NSCLC patients was 2.2%, and the types of EGFR Ex20ins mutation were highly heterogeneous. Citation Format: shun xu, Zhichao Fu. The landscape of EGFR exon 20 insertion mutations in Chinese patients with non-small cell lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5838.

The efficacy and safety of taletrectinib in patients with TKI-naïve or crizotinib-pretreated ROS1-positive non–small cell lung cancer (NSCLC).

8572 Background: Taletrectinib (AB-106 / DS-6051b) is a next-generation, potent, CNS- penetrant, selective ROS1 tyrosine kinase inhibitor. The ongoing TRUST study (NCT04395677) is a multicenter, open-label, single-arm, Phase 2 study of taletrectinib in Chinese ROS1-positive NSCLC patients who are TKI -naïve or crizotinib-pretreated. Here we present the updated efficacy and safety results of the study. Methods: The eligible ROS1-positive NSCLC patients were enrolled into either TKI-naïve or crizotinib-pretreated cohorts, and treated with taletrectinib 600mg once daily. The study endpoints included overall response rate (ORR), duration of response (DOR), disease control rate (DCR), overall intracranial response rate (IC-ORR), progression-free survival (PFS), and safety profile. Results: As of the data cutoff date of September 7, 2021, 61 of the 86 stage IV patients enrolled in the study have at least three postbaseline tumor assessment of which 40 patients in the TKI-naïve cohort, and 21 patients in the crizotinib-pretreated cohort (50% patients having at least one prior chemotherapy). In the TKI -naïve cohort, the confirmed ORR by investigators per RECIST 1.1 was 90.0%: [95%CI: 76.3%; 97.2%] (36/40); and the DCR was 95% [95%CI: 83.1%; 99.4%] (38/40). In the crizotinib-pretreated cohort, the confirmed ORR by investigators was 47.6% [95%CI: 25.7%; 70.2%] (10/21); and DCR was 76.2%: [52.8%; 91.8%] (16/21). The mDOR and mPFS are not reached yet for both cohorts. Of 6 patients having brain metastasis and measurable target brain lesions at baseline, the intracranial ORR and IC-DCR were 83.3% and 100%, respectively. Of 4 patients with ROS1 G2032R mutation, 3 patients achieved partial response (PR), and 1 patient achieved stable disease (SD). The most common treatment-related adverse events (TRAEs) include diarrhea, nausea, vomiting, transaminase elevation, anemia, neutrophil count decrease, etc. were Grade 1 or 2, and the most common AEs (below 10%) were ALT/AST increased but reversible. Conclusions: Taletrectinib demonstrated meaningful clinical efficacy in both TKI-naïve and crizotinib-pretreated ROS1 positive NSCLC patients. In particular, taletrectinib showed clinical effectiveness in patients with ROS1 secondary G2032 mutations and patients with brain metastasis. Taletrectinib was well tolerated in this patient population. Clinical trial information: NCT04395677.

Maximum somatic allele frequency-adjusted blood-based tumor mutational burden balances the effect of intratumor heterogeneity on response to immune checkpoint Inhibitors in non-small cell lung cancer patients.

e21137 Background: ctDNA abundance can influence the accuracy of blood-based tumor mutational burden (bTMB), driving a paradox of bTMB in predicting response and survival benefit of patients with non-small cell lung cancer (NSCLC) receiving immune checkpoint inhibitors (ICIs) therapy. However, the optimal algorithm of ctDNA adjusted bTMB remains largely unestablished. We aimed to develop a novel approach to optimize the calculation of bTMB by integrating maximum somatic allele frequency (MSAF) to better differentiate the ICI-beneficial NSCLC patients, as well as explore the correlated mechanism. Methods: A 1021-gene panel-based targeted capture sequencing was utilized to evaluate the correlation between MSAF and bTMB based on blood samples in 1679 Chinese NSCLC patients (GCGD database, N = 1679). The establishment of MSAF-adjusted bTMB (Ma-bTMB) was derived from three independent NSCLC cohorts treated with programmed death ligand 1 (PD-L1) or the programmed death 1 (PD-1) inhibitors, including POPLAR cohort (N = 231) as training set, and OAK (N = 642) and Wang (N = 81) cohorts as validation sets separately. PyClone was employed to estimate clonal and subclonal populations. Results: MSAF demonstrated a modest positive correlation between bTMB and MSAF (Spearman’s R = 0.41, P < 0.001, GCGD cohort) and was negatively correlated with survival benefit (Spearman’s rank sum test, overall survival (OS): R = −0.39, P < 0.001; progression-free survival (PFS): R = −0.41, P < 0.001, Wang cohort). Patients with high Ma-bTMB (Ma-bTMB-H) demonstrated improved survival outcomes of anti-PD(L)-1 therapy compared to chemotherapy in POPLAR (PFS, hazard ratio (HR) = 0.63, interaction P = 0.030; OS, HR = 0.44, interaction P = 0.020), which was validated in OAK cohorts (PFS, HR = 0.72, interaction P = 0.040; OS, HR = 0.50, interaction P = 0.010). In addition, Ma-bTMB-H was associated with a better clinical benefit compared to low Ma-bTMB (Ma-bTMB-L) in Wang cohort (PFS, HR = 0.55, P = 0.012; OS, HR = 0.46, P = 0.036). Furthermore, there was a positive correlation between intratumor heterogeneity (ITH) and MSAF (R = 0.37, P < 0.001) in GCGD database, and the effect of ITH on Ma-bTMB (subclones, P = 0.57; subclonal mutations, P = 0.8) was substantially reduced compared to traditional bTMB (subclones, P < 0.001; subclonal mutations, P < 0.001) in Wang cohort. Conclusions: We developed and validated Ma-bTMB, a convenient, readily available, non-invasive predictive biomarker, which reduced the confounding effect of ITH and could effectively differentiate beneficiaries of anti-PD(L)1 therapy, warranting investigation in future clinical trials. Clinical trial information: NCC2018-092.

The landscape of NRG1 fusions based on NGS in Chinese solid tumor patients.

e15073 Background: Neuregulin 1 gene ( NRG1) fusions are oncogenic in various tumor types and represent an emerging potential therapeutic target. In the previous reports, NRG1 fusions are overall rare (0.12%) in the Western population, being seen most frequently in NSCLCs. The incidence of NRG1 fusions in a variety of solid tumors based on NGS has been explored limitedly in Chinese patients. Methods: FFPE samples and matched peripheral blood were collected for NGS based 450 cancer genes panel assay and RNA panel assay.Somatic variants were analyzed following CAP/CLIA-certificated workflows, including Single Nucleotide Variant (SNV), Copy Number Variation (CNV), large insertion and deletions (Lindel) and gene rearrangements. Results: A total of 47 patients harboring NRG1 fusions and four of them were detected in RNA level. Non-small cell lung cancer (NSCLC) was the most common cancer type with the incidence of 0.19% (25/13089). The followed cancer types were bone sarcoma, breast carcinoma, pancreatic adenocarcinoma and colorectal carcinoma with the frequency of 0.30% (3/973), 0.16% (3/1850), 0.14% (3/2098) and 0.07% (3/4344) respectively. CD74 (10.1%), SLC34A2 (10.1%) and WRN (4.3%) represented the most common NRG1 fusion partners, other known partners contained CDH1, HMBOX1, ADAM5 and UNC5D. In total, 76.6% of the partners were novel partners, and the most common break points of NRG1 were intron5 and intron1. The 47 NRG1 fusion patients evenly distributed in female (49%) and male (51%), and 44.7% were at advanced stage (stage ≥ III). The median age was 57 years old (range, 8-86 years old) and the median TMB was 3.3 muts/Mb (range, 0-30.5). TP53 (48.9%), CDKN2A (14.9%) and ERBB2/FGFR1/MUC16/SMAD4 (12.8%) were the most common co-occurred mutated gene. In the alterations of ERBB2, 50% were amplifications and 2 patients were breast carcinoma. Only one patient showed ALK fusion and one showed FGFR1 fusion. Among all patients, 8.5% included p.G12X mutation of KRAS and 10.6% included alterations of EGFR with two L858R and two 19del mutations. Conclusions: This study revealed NRG1 fusions in approximately 0.19% of Chinese NSCLC tumor pts and presented the frequency of same common tumors. Also the genomic and clinical feature were analysed. NGS panel sequencing and OrigiFus algorithm showed the advantage of detecting NRG1 fusion and providing structure information of partners which could potentially guide more precise treatment options.

Molecular and clinical characteristics of IDH mutations in Chinese NSCLC patients and potential treatment strategies.

Isocitrate dehydrogenase (IDH) is an appealing target for anticancer therapy, and IDH (IDH1/2) inhibitors have been approved for targeted therapy of acute myeloid leukemia (AML) and Cholangiocarcinoma. The therapeutic potential of IDH inhibitors for non-small-cell lung cancer (NSCLC) patients is under active clinical investigation. Thus, it would be necessary and meaningful to study the molecular and clinical characteristics of IDH mutation in NSCLC patients, especially in the Chinese population. A total of 17,978 Chinese patients with NSCLC who underwent next -generation sequencing (NGS) testing were retrospectively reviewed. We identified 161 unique IDH mutations in 361 of 17,978 patients (2.01%). Common active-site mutations, including IDH1R100 , IDH1R132 , IDH2R140 , and IDH2R172 , were detected in 154 patients (0.86%) and were associated with male sex (p=0.004) and older age (p=0.02). The IDH mutation spectra observed in NSCLC were quite different from those in glioma or AML. Patients with IDH active-site mutations exhibited significantly higher coalterations in KRAS (p. G12/13/61, 22.1% vs. 8.2%, p < 0.001) or BRAF (p. V600E, 6.5% vs. 1.0%, p < 0.001), but significantly lower coalterations in activating EGFR (e18-e20, 22.7 vs. 37.9%, p < 0.001) than IDH wild-type patients. Furthermore, we found that active-site IDH mutations were correlated with a short PFS (2-5.6 months) and short OS (2-9.5 months), which may arise as a resistance mechanism against common targeted drugs. In vitro, we experimentally observed that the combination of an IDH inhibitor and EGFR TKI could better inhibit lung cancer cell proliferation than an EGFR TKI alone. Taken together, this study reveals the molecular and clinical characteristics of IDH mutations in Chinese NSCLC patients and provides a theoretical basis for IDH-directed treatment. The potential of IDH mutations as response markers for targeted therapy warrants further investigation.

Prognostic Factors and Survival Benefits of Antitumor Treatments for Advanced Non-Small Cell Lung Cancer Patients With Central Nervous System Metastasis With or Without Driver Genes: A Chinese Single-Center Cohort Study.

BackgroundThe prognosis of non-small cell lung cancer (NSCLC) patients with central nervous system (CNS) metastasis is poor. The treatment for CNS metastasis could prolong the overall survival of NSCLC patients. We aimed to investigate the prognostic factors of Chinese NSCLC patients with CNS metastasis and the survival benefits of various treatments for CNS metastasis in NSCLC patients with or without driver genes.MethodsBased on the CAPTRA-Lung database, NSCLC patients with CNS metastasis admitted at the Peking Union Medical College Hospital between January 2010 and October 2018 were enrolled in the study. The prognostic factors were analyzed using univariate and multivariate Cox regression analyses.ResultsOverall, 418 patients were enrolled in the study. A total of 206 patients (49.3%) had CNS metastasis with positive driver genes, while 97 patients (23.2%) had negative driver genes. The median survival time after CNS metastasis was 20.8 months. In the multivariable analysis, an Eastern Cooperative Oncology Group performance status of ≥2 (hazard ratio [HR]: 1.750, 95% confidence interval [CI]: 1.184-2.588, P=0.005), number of CNS metastases ≥5 (HR: 1.448, 95% CI: 1.084 -1.934, P=0.012), and CNS metastasis developed during treatment (HR: 1.619, 95% CI: 1.232-2.129, P=0.001) were independent risk factors for poor survival. Lung adenocarcinoma (HR: 0.490, 95% CI: 0.279-0.861, P=0.013) and driver gene positivity (HR: 0.464, 95% CI: 0.302-0.715, P=0.001) were independent predictors of prolonged survival. Radiotherapy for CNS metastasis showed a survival benefit in NSCLC patients in the entire groups (HR: 0.472, 95% CI: 0.360-0.619, P <0.001), and in patients with positive driver genes.ConclusionPerformance status, number of CNS metastases, timing of CNS metastasis, histological subtype, and driver gene status are prognostic factors for NSCLC patients with CNS metastasis. Furthermore, radiotherapy improved the survival in NSCLC patients with CNS metastasis.

Distinct Functional Metagenomic Markers Predict the Responsiveness to Anti-PD-1 Therapy in Chinese Non-Small Cell Lung Cancer Patients.

BackgroundProgrammed death 1 (PD-1) and the ligand of PD-1 (PD-L1) are central targets for immune-checkpoint therapy (ICT) blocking immune evasion-related pathways elicited by tumor cells. A number of PD-1 inhibitors have been developed, but the efficacy of these inhibitors varies considerably and is typically below 50%. The efficacy of ICT has been shown to be dependent on the gut microbiota, and experiments using mouse models have even demonstrated that modulation of the gut microbiota may improve efficacy of ICT.MethodsWe followed a Han Chinese cohort of 85 advanced non-small cell lung cancer (NSCLC) patients, who received anti-PD-1 antibodies. Tumor biopsies were collected before treatment initiation for whole exon sequencing and variant detection. Fecal samples collected biweekly during the period of anti-PD-1 antibody administration were used for metagenomic sequencing. We established gut microbiome abundance profiles for identification of significant associations between specific microbial taxa, potential functionality, and treatment responses. A prediction model based on random forest was trained using selected markers discriminating between the different response groups.ResultsNSCLC patients treated with antibiotics exhibited the shortest survival time. Low level of tumor-mutation burden and high expression level of HLA-E significantly reduced progression-free survival. We identified metagenomic species and functional pathways that differed in abundance in relation to responses to ICT. Data on differential enrichment of taxa and predicted microbial functions in NSCLC patients responding or non-responding to ICT allowed the establishment of random forest algorithm-adopted models robustly predicting the probability of whether or not a given patient would benefit from ICT.ConclusionsOverall, our results identified links between gut microbial composition and immunotherapy efficacy in Chinese NSCLC patients indicating the potential for such analyses to predict outcome prior to ICT.

Changes in serum amino acid levels in non-small cell lung cancer: a case-control study in Chinese population.

BackgroundPrevious studies have shown the alteration of amino acid (AA) profile in patients with non-small cell lung cancer (NSCLC). However, there is little data regarding AA profile in NSCLC in Chinese population. The aim of this study was to evaluate AA profile in Chinese NSCLC patients, explore its utility in sample classification and further discuss its related metabolic pathways.MethodsThe concentrations of 22 AAs in serum samples from 200 patients with NSCLC and 202 healthy controls were determined by liquid chromatography-tandem mass spectrometer (LC-MS/MS). AA levels in different tumor stages and histological types were also discussed. The performance of AA panel in classifying the cases and controls was evaluated in the training data set and validation data set based on the receiver operating characteristic (ROC) curve, and the important metabolic pathways were identified.ResultsThe concentrations of tryptophan (Trp), phenylalanine (Phe), isoleucine (Ile), glycine (Gly), serine (Ser), aspartic acid (Asp), asparagine (Asn), cystein (Cys), glutamic acid (Glu), ornithine (Orn) and citrulline (Cit) were significantly altered in NSCLC patients compared with controls (all P-FDR < 0.05). Among these, four AAs including Asp, Cys, Glu and Orn were substantially up-regulated in NSCLC patients (FC ≥ 1.2). AA levels were significantly altered in patients with late-stage NSCLC, but not in those with early-stage when comparing with healthy controls. In terms of histological type, these AAs were altered in both adenocarcinoma and squamous cell carcinoma. For discrimination of NSCLC from controls, the area under the ROC curve (AUC) was 0.80 (95% CI [0.74–0.85]) in the training data set and 0.79 (95%CI [0.71–0.87]) in the validation data set. The AUCs for early-stage and late-stage NSCLC were 0.75 (95% CI [0.68–0.81]) and 0.86 (95% CI [0.82–0.91]), respectively. Moreover, the model showed a better performance in the classification of squamous cell carcinoma (AUC = 0.90, 95% CI [0.85–0.95]) than adenocarcinoma (AUC = 0.77, 95% CI [0.71–0.82]) from controls. Three important metabolic pathways were involved in the alteration of AA profile, including Gly, Ser and Thr metabolism; Ala, Asp and Glu metabolism; and Arg biosynthesis.ConclusionsThe levels of several AAs in serum were altered in Chinese NSCLC patients. These altered AAs may be utilized to classify the cases from the controls. Gly, Ser and Thr metabolism; Ala, Asp and Glu metabolism and Arg biosynthesis pathways may play roles in metabolism of the NSCLC patient.

Correlation of PD-L1 Expression with Clinicopathological and Genomic Features in Chinese Non-Small-Cell Lung Cancer.

Programmed cell death 1 ligand 1 (PD-L1) has been approved as predictive biomarker for non-small-cell lung cancer (NSCLC) patients treated with PD-(L)1 blockade therapy. The clinical/genomic features associated with PD-L1 are not well studied. Genomic profiling of tumor biopsies from 883 Chinese NSCLC patients was performed by targeted next-generation sequencing. Immunohistochemical analysis was conducted to evaluate PD-L1 expression levels using antibodies Dako 22C3 and 28-8, respectively. Our study showed distinct correlation between PD-L1 expression and clinical/genomic characteristics when using different PD-L1 antibodies and in different histological subtypes including adenocarcinoma (ADC) and squamous cell carcinoma (SCC), respectively. PD-L1 high expression (22C3) was associated with male and lymph node metastasis only in ADC patients. Furthermore, mutations of TP53 and KRAS, KIF5B-RET fusion, copy number gains of PD-L1 and PD-L2, and arm-level amplifications of chr.12p were significantly associated with PD-L1 positive status in ADC patients. For SCC patients, the gain of EGFR and MDM2 and loss of PTPRD were negatively associated with PD-L1 expression. We also compared our results with other studies and found conflicting results presumably because of the multiplicity of antibody clones and platforms, the difference of cutoffs for assigning PD-L1 expression levels, and the variation in study populations. Our study can help to understand the utility and validity of PD-L1 as biomarker of response to immune checkpoint inhibitors.

Clinicopathologic characteristics and diagnostic methods of RET rearrangement in Chinese non-small cell lung cancer patients.

BackgroundRearranged during transfection (RET) rearrangement has been identified as one of the crucial oncogenic drivers in non-small cell lung cancer (NSCLC). Recently, two highly selective RET inhibitors have been approved by the US Food and Drug Administration and demonstrated remarkable responses. However, the clinical characteristics, outcomes and optimal diagnostic method of RET-rearrangements are not well understood. This study sought to evaluate the prevalence and characteristics of RET rearrangement, identify an effective diagnostic method for it, and correlate its presence with outcomes.MethodsA total of 9,431 Chinese NSCLCs from two cancer centers who have undertaken targeted DNA-NGS were enrolled and 167 RET-positive cases were screened. Non-canonical RET rearrangements were confirmed by targeted RNA-NGS. If material was sufficient, positive cases were analyzed by fluorescence in situ hybridization (FISH) (n=30) and immunohistochemistry (IHC) (n=57). Clinicopathologic characteristics, molecular profiling and treatment outcomes of RET rearrangement were evaluated.ResultsThe prevalence of RET rearrangement was 1.52% (138/9,101) in unfiltered cases and 8.79% (29/330) in EGFR/KRAS/BRAF/ALK-negative cases. RET rearrangement was common in females, never smokers, and lung adenocarcinoma patients. Additionally, 40.3% of stage IV RET-rearranged NSCLC patients developed brain metastases. TP53 was the most common concurrent mutation, and 8 patients harbored concurrent driver oncogenic alterations, including EGFR (N=5), KRAS (N=2), and ALK (N=1). Non-canonical fusion partners were identified in 13.8% (23/167) of cases by DNA-based NGS, and RNA-based NGS identified 3 new partners (EPS8, GOLGA5, and TNIP1). The concordance of FISH and NGS was 83.3% (25/30), while the concordance of IHC and NGS was only 28.1% (16/57). Both IHC and FISH demonstrated lower sensitivity for NCOA4-/other-RET fusions. The CCDC6-RET subgroup had significantly longer progression-free survival than the KIF5B-RET subgroup, both after chemotherapy (23 vs. 9.7 months; P=0.014).ConclusionsRET rearrangement occurs in 1.52% of Chinese NSCLCs and has identifiable clinicopathologic characteristics. RET IHC has a low sensitivity, disavowing its use in routine practice. While NGS and FISH has good performance in identifying RET rearrangement. Both IHC and FISH demonstrated lower sensitivity for NCOA4-/others-RET fusions. Clinical benefit with chemotherapy is different between CCDC6-RET and KIF5B-RET fusion patients, optimal treatment should be considered when selecting therapies for patients with RET-rearranged lung cancers.

The genomic characteristics of RET fusion positive tumors in Chinese non-small cell lung cancer (NSCLC) patients

BackgroundApproximately 1–2% of non-small cell lung cancer (NSCLC) patients harbor RET (rearranged during transfection) fusions. The oncogenic RET fusions could lead to constitutive kinase activation and oncogenesis.Methods1746 Chinese NSCLC patients were analyzed in this study. Tumor tissues were collected, and were formalin fixed, paraffin-embedded (FFPE) and archived. Peripheral blood (PB) samples were also collected from each patient as control. In addition, we selected 17 of them for cfDNA NGS testing and 14 tumor samples for immunohistochemistry testing using PD-L1 rabbit monoclonal antibody, clones 28-8 (Abcam, Cambridge, UK).ResultsOf the 1746 NSCLC cases, RET rearrangements were identified in 25 cases (1.43%) with locally advanced or metastatic NSCLC, of which 20 (80%) were female. We found that 14 out of 25 patients had an KIF5B-RET fusion, with KIF5B exon15-RET exon12, KIF5B exon23-RET exon12, and KIF5B exon24-RET exon11 detected in 14, 3, and 1 patients, respectively. We also identified one novel RET fusion partner PLCE1 and 4 intergenic-breakpoint fusions.ConclusionIn this study, using the hybrid capture based next generation sequencing (NGS) techniques, we revealed the genomic profiling for the patients with RET fusion-positive NSCLC. To the best of our knowledge, this is the first study that exhibited the detailed breakpoints of Chinese NSCLC patients with RET rearrangement, and we found a novel new partner PLCE1. The results provided genomic information for patients with RET fusion which is significant for personalized clinical management in the era of precision medicine.

Analysis of Genetic Variants and the ceRNA Network of miR-9 in Non-Small Cell Lung Cancer.

Objective: To explore the role of single-nucleotide polymorphisms (SNPs) in hsa-miR-9 in non-small cell lung cancer (NSCLC). Methods: Log-rank and Cox regression analyses were conducted to assess the association of four functional SNPs of miR-9 with overall survival (OS) of Chinese patients with NSCLC. A reporter luciferase assay was performed to examine the relationship between the SNPs and transcriptional activity of miR-9. The expression of miR-9 in cells was detected by quantitative real-time PCR assay. Xenograft model was established in nude mice, which were treated with Lv-MiR-9-mimics or Lv-miR-9-inhibitor. A long noncoding RNA (lncRNA)-miR-9-messenger RNA (mRNA) competing endogenous RNA (ceRNA) network was established based on bioinformatics analyses. Results: We found that rs1501672 was associated with the prognosis of 1001 Chinese NSCLC patients (A>G, additive model: adjusted hazard ratio = 0.89, 95% confidence interval = 0.79-1.00, p = 0.056). Luciferase reporter assay showed higher luciferase activity with wild A allele than that with mutant G allele in 293T, SPC-A1, and A549 cell lines. The miR-9 level was significantly higher in lung cancer cells than normal lung cells. miR-9 was also over expressed in lung cancer tissue according to The Cancer Genome Atlas and gene expression omnibus databases. Xenograft models based on H1299 cells showed that lv-miR-9-inhibitor significantly decreased tumor growth compared with the lv-miR-9-NC group (p < 0.001). Bioinformatics analysis showed that one target gene leukemia inhibitory factor receptor and two lncRNAs (KIAA0087 and GVINP1) were associated with OS of NSCLC patients. Conclusion: The rs1501672 of miR-9 was associated with the prognosis of NSCLC patients in the Chinese population. The lncRNA-miR-9-mRNA ceRNA network revealed potential molecular biological regulation pathways and prognostic biomarkers for NSCLC.

Prognostic evaluation of the proposed residual tumor classification in a Chinese non-small cell lung cancer population.

This study aimed to validate the R classification including uncertain resection (R-un) proposed by the International Association for the Study of Lung Cancer (IASLC) in a Chinese non-small cell lung cancer (NSCLC) population. The study retrospectively investigated a 2009-2013 single-institutional NSCLC resection cohort in China. After reclassification, recurrence-free survival (RFS) and overall survival (OS) were calculated using survival analyses and compared with those using the 2005 version IASLC R classification. Under the proposed stratification, 3819 (72.1%) individuals were classified as R0, 1371 (25.9%) as R-un, 71 (1.3%) as R1, and 32 (0.6%) as R2. The 5-year OS probabilities for the R0, R-un, and R1/R2 groups were 71%, 46%, and 34%, respectively. The prognostic stratification remained significant in the fully adjusted Cox models (p < 0.001). Compared with the original classification, Harrell's concordance index of reclassification improved significantly, from 0.508 to 0.679 for RFS and from 0.510 to 0.692 for OS (RFS: p = 0.007; OS: p = 0.001). The survival analysis showed that R-un patients with highest mediastinal lymph node station metastasis had significantly worse survival than R0 patients with mediastinal nodal metastasis (RFS: 44 vs. 36 months, hazard ratio [HR]: 1.29, p < 0.001; OS: 59 vs. 50 months, HR: 1.34, p < 0.001). Cox proportional hazards regression analysis showed that highest mediastinal lymph node station metastasis was an independent risk factor for RFS (HR: 1.22) and OS (HR: 1.25). The proposed R classification showed valid prognostic stratification, including highest mediastinal nodal station metastasis.

Investigation of PALB2 Mutation and Correlation With Immunotherapy Biomarker in Chinese Non-Small Cell Lung Cancer Patients.

BackgroundPALB2, a gene in the homologous recombination repair (HRR) pathway of the DNA damage response (DDR), is associated with the efficacy of platinum-based chemotherapy, immunotherapy, and PARP inhibitor therapy in several tumors. However, the PALB2 characteristics, its correlation with immunotherapy biomarker, and the prognostic effect of immunotherapy in non-small cell lung cancer (NSCLC) were unknown.MethodsTumor tissue samples from advanced Chinese NSCLC patients were analyzed by next-generation sequencing (NGS) (panel on 381/733-gene). Tumor mutation burden (TMB) is defined as the total number of somatic non-synonymous mutations in the coding region. Microsatellite instability (MSI) was evaluated by NGS of 500 known MSI loci. Programmed Cell Death-Ligand 1 (PD-L1) expression was evaluated using immunohistochemistry (Dako 22C3 or SP263). One independent cohort (Rizvi2018.NSCLC.240.NGS cohort) containing genomic and clinical data from 240 patients with advanced NSCLC and two cohorts (the OAK and POPLAR study cohort) containing genomic and clinical data from 429 patients with advanced NSCLC were used to analyze the prognostic effect of PALB2 on immunotherapy.ResultsGenetic mutation of 5,227 NSCLC patients were analyzed using NGS, of which 162 (3.1%) harbored germline PALB2 mutation (PALB2gmut) and 87 (1.66%) harbored somatic PALB2 mutation (PALB2smut). In NSCLC patients with PALB2gmut and PALB2smut, the most frequently mutated gene was TP53 (65%, 64%). PALB2smut (14.52 Muts/Mb) was associated with higher TMB (p < 0.001) than PALB wild-type (PALB2wt) (6.15 Muts/Mb). However, there was no significant difference in TMB between PALB2gmut (6.45 Muts/Mb) and PALB2wt (6.15 Muts/Mb) (p = 0.64). There was no difference in PD-L1 expression among PALB2gmut, PALB2smut, and PALB2wt. In the Rizvi2018.NSCLC.240.NGS cohort, there was no difference in progression-free survival (PFS) (HR =1.06, p = 0.93) between PALB2 mutation (3.15 months) and PALB2wt (3.17 months). The OAK and POPLAR study cohort of NSCLC patients showed that there was no difference in overall survival (OS) (HR =1.1, p = 0.75) between PALB2 mutation (10.38 months) and PALB2wt (11.07 months).ConclusionsThese findings suggest that PALB2 may not be used as a biomarker for determining prognosis on immunotherapy in NSCLC.

The co-mutation of EGFR and tumor-related genes leads to a worse prognosis and a higher level of tumor mutational burden in Chinese non-small cell lung cancer patients.

BackgroundLung cancer is the leading cause of cancer mortality in China. The clinicopathologic features and genetic profile of Chinese lung cancer patients need to be investigated. This study evaluated the gene mutation profile, analyzed the frequency of concurrent genes in epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer (NSCLC) patients, and determined its prognostic value.MethodsWe collected the clinical data from 151 initially diagnosed patients NSCLC. Tumor samples underwent targeted next-generation sequencing (NGS). Progression-free survival (PFS) and overall survival (OS) were analyzed using the Kaplan-Meier method.ResultsAmong the 151 participants, the mutational profile revealed alterations in 29 genes, where TP53 (37.09%) and EGFR (30.46%) exhibited the highest mutation rates. Mutations in the EGFR gene were most prevalent (40%) in adenocarcinoma (LUAD) and were only present in 8.8% of participants with squamous cell carcinoma (LUSC). The most frequently mutated genes in LUAD patients were TP53 (47%), followed by KRAS (11.7%). In all 39 participants with EGFR mutations, TP53, KRAS, PIK3CA, APC, and FBXW7 were also mutated. Those with only EGFR mutation appeared to have a better prognosis; however, the difference was not statistically significant. Tumor mutational burden (TMB) was roughly significantly increased in patients who harbored EGFR and other mutant driver genes, compared with only EGFR mutant patients. The TMB value was significantly higher in those with P53 mutation than in P53 wild-type patients.ConclusionsWe described the genetic profiles of NSCLC and compared the difference in genetic profiles between LUAD and LUSC. The concomitant genetic alterations might be a poor prognostic factor for patients with EGFR mutation, and TMB might be prognostically related to the co-mutations of EGFR and other genes.

Predictable Roles of Peripheral IgM Memory B Cells for the Responses to Anti-PD-1 Monotherapy Against Advanced Non-Small Cell Lung Cancer.

Tumor-infiltrating B cells and tertiary lymphoid structures have been identified to predict the responses to immune checkpoint inhibitors (ICIs) in cancer immunotherapy. Considering the feasibility of sample collection, whether peripheral B cell signatures are associated with the responses to ICI therapy remains unclear. Herein, we have defined peripheral B cell signatures in advanced non-small cell lung cancer (NSCLC) patients receiving anti-PD-1 monotherapy and investigated their associations with clinical efficacy. It was found that the percentages of B cells before the treatment (baseline) were significantly higher (P = 0.004) in responder (R, n = 17) than those in non-responder (NonR, n = 33) NSCLC patients in a discovery cohort. Moreover, the percentages of baseline IgM+ memory B cells were higher (P < 0.001) in R group than those in NonR group, and associated with a longer progression free survival (PFS) (P = 0.003). By logistic regression analysis peripheral baseline IgM+ memory B cells were identified as an independent prognostic factor (P = 0.002) for the prediction of the responses to anti-PD-1 monotherapy with the AUC value of 0.791, which was further validated in another anti-PD-1 monotherapy cohort (P = 0.011, n = 70) whereas no significance was observed in patients receiving anti-PD-L1 monotherapy (P = 0.135, n = 30). Therefore, our data suggest the roles of peripheral IgM+ memory B cells in predicting the responses to anti-PD-1 treatment in Chinese advanced NSCLC patients.

P59.07 Mutation Profile of BRAF in Chinese Non-Small Cell Lung Cancer Patients

BRAF mutation is one of the most common driver gene mutations in non-small cell lung cancer (NSCLC) patients, especially in adenocarcinoma. BRAF alterations have been identified with the clinical application of next generation sequencing (NGS),however, mutation profile and co-occurring genomic alterations of BRAF have not been fully understood in Chinese non-small cell lung cancer patients. We enrolled 14703 Chinese NSCLC patients with confirmed histology subtype of adenocarcinoma, squamous carcinoma and large cell carcinoma. FFPE samples and matched peripheral blood or plasma were sequenced for NGS based 1021 cancer genes panel assay. Comprehensive genomic profiling including single nucleotide variants (SNV), short and long insertion and deletion (Indel), copy number variations (CNV) and gene arrangement/fusion were analyzed. 1.78% (261/14703) of Chinese NSCLC patients harbored at least one BRAF genomic alteration, which was mainly composed of patient with SNVs and Indels (97.3%, 254 patients), copy number variations (16.1%, 42 patients), and gene rearrangements (5.0%, 13 patients). None BRAF CNV was detected. Of the 42 patients carried CNV, 38 of them carried both CNV and BRAF SNV/Indel, whereas two of them carried both CNV and gene arrangement/fusion and two of patients carried aforementioned three types of alteration. BRAF V600E were the most common BRAF mutations, which accounted for 36% of all BRAF mutation, respectively. The most common resistant alteration G469A accounted for 11%. A total of nine types of BRAF rearrangement were detected from eight patients. AGK-BRAF were the most common BRAF rearrangement, which accounted for 36% of all BRAF rearrangement. Further analysis of co-occurring BRAF mutations revealed that of BRAF mutated Chinese NSCLC patients harbored both BRAF mutations and other driver gene mutation, such as EGFR, KRAS, PI3KCA. This study revealed BRAF variation in approximately 1.78% of Chinese NSCLC patients. BRAF V600E were the most common BRAF mutations, which accounted for 36% of all BRAF mutation. BRAF mutated Chinese NSCLC patients harbored both BRAF mutations and other driver gene mutation, such as EGFR, KRAS, PI3KCA.

P70.19 Clinicopathologic Characteristics of Patients With LRP1B Mutations in Chinese Non-Small Cell Lung Cancer Patients

The low-density lipoprotein receptor-related protein 1B (LRP1B), which encoding endocytic LDL-family receptor, is among the top 10 significantly mutated genes in human cancer. It has been demonstrated that LRP1B could bind to multiple extracellular ligands. Frequently inactivationmutation of LRP1B was observed in melanoma, lung cancer, esophagus squamous-cell carcinoma, head and neck squamous cancer, gastric cacner, and so on. The aim of this study is to investigate mutations and prognosis of non-small-cell lung cancer (NSCLC) harboring LRP1B mutations.

P70.13 Different Types of ERBB3 Mutations in Chinese Non-Small Cell Lung Cancer Patients

HER3, a member of the EGFR family of receptor tyrosine kinases coded by the ERBB3 gene, plays an important role in cancer, despite its lack of intrinsic kinase activity. As with genes coding for potential heterodimeric partners of HER3, EGFR, and HER2, oncogenic mutations of ERBB3 have been explored by several studies. The prevalence of these mutations in non-small-cell lung cancer (NSCLC) is unknown. The aim of this study is to investigate mutations and prognosis of NSCLC harboring ERBB3 mutations. A total of 1402 patients with non-small-cell lung cancer were recruited between July 2012 and December 2018. The status of ERBB3 mutations and other genes were detected by next generation sequencing. ERBB3 gene mutation rate was 1.14% (16/1402) in non-small cell lung cancer, including D297N (1 patient), L841I (1 patient), R833G (1 patient), V653I (1 patient), R81Efs*3 (1 patient), R391L (1 patient), D1155E (1 patient), G994S (1 patient), Q849R (1 patient), C246* (1 patient), R1125W (1 patient), R541Q (1 patient), P276H (1 patient), L841I (1 patient), A232V (1 patient) and C327S (1 patient), and median overall survival (OS) for these patients was 17.0 months. Among them, all patients were ERBB3 gene with co-occurring mutations. Among them, all patients were ERBB3 gene with co-occurring mutations. Briefly, patients with (n=5) or without (n=11) co-occurring EGFR mutations had a median OS of not up to now and 17.0 months respectively (P=0.90); patients with (n=13) or without (n=3) co-occurring TP53 mutations had a median OS of 17.0 months and 14.5 months respectively (P=0.88); patients with (n=5) or without (n=11) co-occurring KRAS mutations had a median OS of 3.0 months and not up to now respectively (P=0.04); patients with (n=3) or without (n=13) co-occurring BRCA2 mutations had a median OS of 17.0 months and not up to now respectively (P=0.74). KRAS accompanied mutations might play a good prognosis in ERBB3 gene mutation NSCLC. Our results show that ERBB3 mutations delineate an aggressive subtype of lung cancer for which a targeted treatment through ERBB3 inhibition might offer new opportunities.

Driver gene alterations profiling of Chinese non-small cell lung cancer and the effects of co-occurring alterations on immunotherapy.

BackgroundMolecular testing for alterations in oncogenic driver genes and targeted therapies have become standard procedures for non‐small cell lung cancer (NSCLC) patients. However, little evidence has shed light on the pattern of co‐existence of driver genes in NSCLC, and whether they may have different tumor features affecting immunotherapy is still unclarified.MethodsGenomic alterations in 14 lung cancer‐related genes were conducted in 3440 Chinese NSCLC patients using next‐generation sequencing. Meanwhile, tumor mutational burden and immunotherapy dataset from the Memorial sloan kettering cancer center (MSKCC) and lung adenocarcinoma dataset from The Cancer Genome Atlas (TCGA) were utilized for analyzing the impact of the co‐occurring alterations on patients’ survival following immunotherapy.ResultsIn this cohort, 90.17% of patients had at least one somatic alteration in the 14 genes, including 51% of co‐occurring alterations. TP53 and epidermal growth factor receptor (EGFR) were the most prevalent genes (54.74% and 53.55%, respectively), followed by KRAS, ERBB2, ALK, PIK3CA, ROS1, RET, MET, BRAF, KIT, FGFR1, PDGFRA, and NRAS. The prevalence of TP53, EGFR, and ERBB2 in our cohort were significantly higher than that from the TCGA database, whereas KRAS, BRAF, and PDGFRA were significantly lower than the latter. Furthermore, the patients who harbored multiple alterations (8.86%, 31/350) in eight driver genes survived longer and have a higher tumor mutation burden compared to the patients with a single alteration. Similar result was found between the patients with co‐occurring alteration of EGFR and other driver genes and the patients with single EGFR alteration. Meanwhile, we found a distinct immune cell infiltration feature between patients with single and multiple driver gene alterations, as well as between patients with only EGFR alteration and co‐occurring groups.ConclusionThis study identified a unique driver gene feature and found patients harboring co‐occurring alterations of EGFR and other driver genes may benefit from immunotherapy, which may provide more therapeutic selections for EGFR‐mutated NSCLC patients and merit additional investigation.