Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a minimally invasive bronchoscopic procedure, well established as a diagnostic modality of first choice for diagnosis ...and staging of non-small cell lung cancer (NSCLC). The therapeutic decisions for advanced NSCLC require comprehensive profiling of actionable mutations, which is currently considered to be an essential part of the diagnostic process. The purpose of this study was to evaluate the utility of EBUS-TBNA cytology specimen for histological subtyping, molecular profiling of NSCLC by massive parallel sequencing (MPS), as well as for PD-L1 analysis. A retrospective review of 806 EBUS bronchoscopies was performed, resulting in a cohort of 132 consecutive patients with EBUS-TBNA specimens showing NSCLC cells in lymph nodes. Data on patient demographics, radiology features of the suspected tumor and mediastinal engagement, lymph nodes sampled, the histopathological subtype of NSCLC, and performed molecular analysis were collected. The EBUS-TBNA specimen proved sufficient for subtyping NSCLC in 83% and analysis of treatment predictive biomarkers in 77% (MPS in 53%). The adequacy of the EBUS-TBNA specimen was 69% for EGFR gene mutation analysis, 49% for analysis of ALK rearrangement, 36% for ROS1 rearrangement, and 33% for analysis of PD-L1. The findings of our study confirm that EBUS-TBNA cytology aspirate is appropriate for diagnosis and subtyping of NSCLC and largely also for treatment predictive molecular testing, although more data is needed on the utility of EBUS cytology specimen for MPS and PD-L1 analysis.
Correct diagnosis of pulmonary tumors is essential for treatment decision and often relies on immunohistochemical markers. We stained tissue microarrays from resected primary lung cancer (n = 665) ...and pulmonary metastases (n = 425) for CK7, CK20, CDX2, CK5, p40, p63, TTF-1, napsin A, GATA3, and PAX8 to systematically assess the diagnostic value of these markers. Primary lung adenocarcinomas expressed TTF-1 in 90% and napsin A in 84% of the cases, whereas 10% were positive for p63, 7% for CDX2, 2% for CK20, and 2% for GATA3. Only 68% of the lung adenocarcinomas were positive for CK7, TTF-1, and napsin A and negative for all other markers. Primary lung squamous cell carcinomas expressed CK5, p40, and p63 in 94%-97% of cases, whereas 44% were positive for CK7, 20% for GATA3, 7% for CDX2, and 3% for TTF-1. Rare cases expressed PAX8, CK20, or napsin A. Pulmonary metastases of colorectal cancer were positive for CK20 in 83% and CDX2 in 99% of the cases. Rare cases expressed CK7, p63, or PAX8, whereas 4% expressed TTF-1. Pulmonary metastases of renal cell carcinomas were positive for PAX8 in 74%, napsin A in 7%, and CK7 in 7% of the cases. Pulmonary metastases of breast cancer were positive for GATA3 in 93% and CK7 in 78% of the cases, whereas 15% expressed CK5. Information on expression and patterns of immunohistochemical markers facilitates histopathological diagnostics. Evidently, unusual immune profiles occur and may lead to incorrect diagnosis.
•Nontypical IHC staining occurs rather uncommonly in pulmonary tumors.•GATA3 is an exception and is expressed in 20% of lung squamous cell carcinomas.•A nontypical pattern is rather common when applying several markers.•For example, 68% of the lung adenocarcinomas are positive for only CK7, TTF-1, and napsin A.
Large cell lung cancer (LCLC) and large cell neuroendocrine carcinoma (LCNEC) constitute a small proportion of NSCLC. The WHO 2015 classification guidelines changed the definition of the debated ...histological subtype LCLC to be based on immunomarkers for adenocarcinoma and squamous cancer. We sought to determine whether these new guidelines also translate into the transcriptional landscape of lung cancer, and LCLC specifically.
Gene expression profiling was performed by using Illumina V4 HT12 microarrays (Illumina, San Diego, CA) on samples from 159 cases (comprising all histological subtypes, including 10 classified as LCLC WHO 2015 and 14 classified as LCNEC according to the WHO 2015 guidelines), with complimentary mutational and immunohistochemical data. Derived transcriptional phenotypes were validated in 199 independent tumors, including six WHO 2015 LCLCs and five LCNECs.
Unsupervised analysis of gene expression data identified a phenotype comprising 90% of WHO 2015 LCLC tumors, with characteristics of poorly differentiated proliferative cancer, a 90% tumor protein p53 gene (TP53) mutation rate, and lack of well-known NSCLC oncogene driver alterations. Validation in independent data confirmed aggregation of WHO 2015 LCLCs in the specific phenotype. For LCNEC tumors, the unsupervised gene expression analysis suggested two different transcriptional patterns corresponding to a proposed genetic division of LCNEC tumors into SCLC-like and NSCLC-like cancer on the basis of TP53 and retinoblastoma 1 gene (RB1) alteration patterns.
Refined classification of LCLC has implications for diagnosis, prognostics, and therapy decisions. Our molecular analyses support the WHO 2015 classification of LCLC and LCNEC tumors, which herein follow different tumorigenic paths and can accordingly be stratified into different transcriptional subgroups, thus linking diagnostic immunohistochemical staining–driven classification with the transcriptional landscape of lung cancer.
Immune checkpoint inhibitors (ICI) targeting programmed cell death-1 or its ligand (PD-L1) have improved outcomes in non-small cell lung cancer (NSCLC). High tumor PD-L1 expression, detected by ...immunohistochemistry (IHC) typically on formalin-fixed paraffin-embedded (FFPE) histological specimens, is linked to better response. Following our previous investigation on PD-L1 in cytological samples, the aim of this study was to further explore the potential impacts of various clinicopathological and molecular factors on PD-L1 expression. Two retrospective NSCLC cohorts of 1131 and 651 specimens, respectively, were investigated for PD-L1 expression (<1%/1−49%/≥50%), sample type, sample site, histological type, and oncogenic driver status. In both cohorts, PD-L1 was positive (≥1%) in 55% of the cases. Adenocarcinomas exhibited lower PD-L1 expression than squamous cell carcinomas (p < 0.0001), while there was no difference between sample types, tumor locations, or between the two cohorts in multivariate analysis (all p ≥ 0.28). Mutational status correlated significantly with PD-L1 expression (p < 0.0001), with the highest expression for KRAS-mutated cases, the lowest for EGFR-mutated, and the KRAS/EGFR wild-type cases in between. There was no difference in PD-L1 levels between different prevalent KRAS mutations (all p ≥ 0.44), while mucinous KRAS-mutated adenocarcinomas exhibited much lower PD-L1 expression than non-mucinous (p < 0.0001). Our data indicate that cytological and histological specimens are comparable for PD-L1 evaluation. Given the impact of KRAS mutations and the mucinous growth pattern on PD-L1 expression, these factors should be further investigated in studies on ICI response.
Among patients who underwent primary surgery for non-small cell lung cancer (NSCLC), recurrent disease is frequent and cannot be accurately predicted solely from TNM stage and histopathological ...features. The aim of this study was to examine the association of tumor markers in pre-operative serum with recurrent disease.
Blood samples were collected prior to lung cancer surgery from 107 patients with stage I-III lung adenocarcinoma surgically treated at Lund University hospital, Lund, Sweden, between 2005 and 2011. The serum tumor markers Carcinoembryonic antigen (CEA), Neuron-specific enolase (NSE), Cancer antigen 125 (CA 125), Human epididymis protein 4 (HE4) and Carbohydrate antigen (CA 19-9) were analyzed retrospectively and clinical follow-up data were collected from patient charts. Forty (37%) patients were diagnosed with recurrent disease.
Sixty-eight (64%) patients had at least one elevated tumor marker prior to surgery. In analysis of disease-free survival (DFS), CA 125 and/or CA 19-9 were significantly associated with recurrent disease adjusted to stage and adjuvant treatment (hazard ratio 2.8, 95% confidence interval 1.4-5.7, p = 0.006).
High pre-operative serum CA 19-9 and/or CA 125 might indicate an increased incidence of recurrent disease in resectable lung adenocarcinomas.
Abstract
Objectives
Immunohistochemical staining against thyroid transcription factor 1 (TTF-1) is often used to distinguish lung adenocarcinoma from squamous cell carcinoma and pulmonary metastasis.
...Methods
TTF-1 expression was examined using the antibody clones 8G7G3/1, SPT24, and SP141 on tissue microarrays from 665 cases of resected lung cancers and 428 pulmonary metastases.
Results
Most lung adenocarcinomas, 89%, 93%, and 93%, were positive with TTF-1 clones 8G7G3/1, SPT24, and SP141, respectively. The corresponding figures for lung squamous cell carcinomas were 0%, 6%, and 8%. In total, five (2%), 19 (7%), and 21 (8%) of the pulmonary metastases from colorectal adenocarcinomas were positive with clones 8G7G3/1, SPT24, and SP141, respectively. Other TTF-1–positive pulmonary metastases (n = 8) were thyroid, urothelial, pancreatic, small bowel, and cervix carcinomas.
Conclusions
TTF-1 expression in lung cancer and pulmonary metastases differs between clones, with 8G7G3/1 being more specific but less sensitive compared with SPT24 and SP141.
Hypoxia occurs frequently in human cancers and promotes stabilization and activation of hypoxia inducible factor (HIF). HIF-1α is specific for the hypoxia response, and its degradation mediated by ...three enzymes EGLN1, EGLN2 and EGLN3. Although EGLNs expression has been found to be related to prognosis of many cancers, few studies examined DNA methylation in EGLNs and its relationship to prognosis of early-stage non-small cell lung cancer (NSCLC). We analyzed EGLNs DNA methylation data from tumor tissue samples of 1,230 early-stage NSCLC patients, as well as gene expression data from The Cancer Genome Atlas. The sliding windows sequential forward feature selection method and weighted random forest were used to screen out the candidate CpG probes in lung adenocarcinomas (LUAD) and lung squamous cell carcinomas patients, respectively, in both discovery and validation phases. Then Cox regression was performed to evaluate the association between DNA methylation and overall survival. Among the 34 CpG probes in EGLNs, DNA methylation at cg25923056
EGLN2
was identified to be significantly associated with LUAD survival (HR = 1.02, 95% CI: 1.01-1.03, P = 9.90 × 10
-5
), and correlated with EGLN2 expression (r = - 0.36, P = 1.52 × 10
-11
). Meanwhile, EGLN2 expression was negatively correlated with HIF1A expression in tumor tissues (r = - 0.30, P = 4.78 × 10
-8
) and significantly (P = 0.037) interacted with HIF1A expression on overall survival. Therefore, DNA methylation of EGLN2- HIF1A is a potential marker for LUAD prognosis and these genes are potential treatment targets for further development of HIF-1α inhibitors in lung cancer therapy.
B‐cell translocation gene 2 (BTG2) is a tumour suppressor protein known to be downregulated in several types of cancer. In this study, we investigated a potential role for BTG2 in early‐stage ...non‐small cell lung cancer (NSCLC) survival. We analysed BTG2 methylation data from 1230 early‐stage NSCLC patients from five international cohorts, as well as gene expression data from 3038 lung cancer cases from multiple cohorts. Three CpG probes (cg01798157, cg06373167, cg23371584) that detected BTG2 hypermethylation in tumour tissues were associated with lower overall survival. The prognostic model based on methylation could distinguish patient survival in the four cohorts hazard ratio (HR) range, 1.51–2.21 and the independent validation set (HR = 1.85). In the expression analysis, BTG2 expression was positively correlated with survival in each cohort (HR range, 0.28–0.68), which we confirmed with meta‐analysis (HR = 0.61, 95% CI 0.54–0.68). The three CpG probes were all negatively correlated with BTG2 expression. Importantly, an integrative model of BTG2 methylation, expression and clinical information showed better predictive ability in the training set and validation set. In conclusion, the methylation and integrated prognostic signatures based on BTG2 are stable and reliable biomarkers for early‐stage NSCLC. They may have new applications for appropriate clinical adjuvant trials and personalized treatments in the future.
In this multicenter study including 1230 tumor samples with methylation data and 3038 cases with gene expression data, we investigated the prognostic role of BTG2 and proposed a prognostic signature based on three CpG probes within BTG2 region and an integrated signature, which significantly stratified patients into low‐ and high‐risk groups and were more pronounced in the cases with adjuvant therapy. These markers may be relevant for developing novel therapies in the future.
The interaction between DNA methylation of tripartite motif containing 27 (cg05293407TRIM27) and smoking has previously been identified to reveal histologically heterogeneous effects of TRIM27 DNA ...methylation on early‐stage non‐small‐cell lung cancer (NSCLC) survival. However, to understand the complex mechanisms underlying NSCLC progression, we searched three‐way interactions. A two‐phase study was adopted to identify three‐way interactions in the form of pack‐year of smoking (number of cigarettes smoked per day × number of years smoked) × cg05293407TRIM27 × epigenome‐wide DNA methylation CpG probe. Two CpG probes were identified with FDR‐q ≤ 0.05 in the discovery phase and P ≤ 0.05 in the validation phase: cg00060500KIAA0226 and cg17479956EXT2. Compared to a prediction model with only clinical information, the model added 42 significant three‐way interactions using a looser criterion (discovery: FDR‐q ≤ 0.10, validation: P ≤ 0.05) had substantially improved the area under the receiver operating characteristic curve (AUC) of the prognostic prediction model for both 3‐year and 5‐year survival. Our research identified the complex interaction effects among multiple environment and epigenetic factors, and provided therapeutic target for NSCLC patients.
We performed a two‐phase designed epigenome‐wide three‐way gene‐smoking interaction study of NSCLC survival and identified two CpG probes (cg00060500KIAA0226 and cg17479956EXT2), together with pack‐year of smoking and cg05293407TRIM27, exhibiting significant three‐way interaction effects. Meanwhile, these significant three‐way interactions substantially improved the area under the receiver operating characteristic curve (AUC) of the prognostic prediction model for both 3‐ and 5‐year survival.
Epigenome‐wide gene–gene (G × G) interactions associated with non‐small‐cell lung cancer (NSCLC) survival may provide insights into molecular mechanisms and therapeutic targets. Hence, we proposed a ...three‐step analytic strategy to identify significant and robust G × G interactions that are relevant to NSCLC survival. In the first step, among 49 billion pairs of DNA methylation probes, we identified 175 775 G × G interactions with PBonferroni ≤ 0.05 in the discovery phase of epigenomic analysis; among them, 15 534 were confirmed with P ≤ 0.05 in the validation phase. In the second step, we further performed a functional validation for these G × G interactions at the gene expression level by way of a two‐phase (discovery and validation) transcriptomic analysis, and confirmed 25 significant G × G interactions enriched in the 6p21.33 and 6p22.1 regions. In the third step, we identified two G × G interactions using the trans‐omics analysis, which had significant (P ≤ 0.05) epigenetic cis‐regulation of transcription and robust G × G interactions at both the epigenetic and transcriptional levels. These interactions were cg14391855 × cg23937960 (βinteraction = 0.018, P = 1.87 × 10−12), which mapped to RELA × HLA‐G (βinteraction = 0.218, P = 8.82 × 10−11) and cg08872738 × cg27077312 (βinteraction = −0.010, P = 1.16 × 10−11), which mapped to TUBA1B × TOMM40 (βinteraction =−0.250, P = 3.83 × 10−10). A trans‐omics mediation analysis revealed that 20.3% of epigenetic effects on NSCLC survival were significantly (P = 0.034) mediated through transcriptional expression. These statistically significant trans‐omics G × G interactions can also discriminate patients with high risk of mortality. In summary, we identified two G × G interactions at both the epigenetic and transcriptional levels, and our findings may provide potential clues for precision treatment of NSCLC.
A three‐step, trans‐omics study identified two gene–gene interactions, cg14391855 × cg23937960 (mapped to RELA × HLA‐G) as well as cg08872738 × cg27077312 (mapped to TUBA1B × TOMM40), which were significantly and robustly associated with NSCLC survival at both the epigenetic and transcriptional levels. Our findings have implications of precision treatment by providing therapeutic targets for early‐stage NSCLC patients.