Supplementary Table S2. Comparison of mRNAs, proteins, microRNAs, and DNA methylation in epithelial and mesenchymal cell lines and related gene ontology.
Supplementary Table S5. Differentially expressed proteins and gene ontology after TGFB treatment.
Supplementary Table S3. Gene and protein expression of epithelial and mesenchymal markers.
Supplementary Methods and References. Description of additional methods and procedures used in the study. Also includes Supplementary References.
Single-cell sequencing provides promising information in tumor evolution and heterogeneity. Even with the recent advances in circulating tumor cell (CTC) technologies, it remains a big challenge to precisely and effectively isolate CTCs for downstream analysis. The Cell RevealTM system integrates an automatic CTC enrichment and staining machine, an AI-assisted automatic CTC scanning and identification system, and an automatic cell picking machine for CTC isolation. H1975 cell line was used for the spiking test. The identification of CTCs and the isolation of target CTCs for genetic sequencing were performed from the peripheral blood of three cancer patients, including two with lung cancer and one with both lung cancer and thyroid cancer. The spiking test revealed a mean recovery rate of 81.81% even with extremely low spiking cell counts with a linear relationship between the spiked cell counts and the recovered cell counts (Y = 0.7241 × X + 19.76, R2 = 0.9984). The three cancer patients had significantly higher TTF-1+ CTCs than healthy volunteers. All target CTCs were successfully isolated by the Cell Picker machine for a subsequent genetic analysis. Six tumor-associated mutations in four genes were detected. The present study reveals the Cell RevealTM platform can precisely identify and isolate target CTCs and then successfully perform single-cell sequencing by using commercially available genetic devices.
An integrative multi-omics database is needed urgently, because focusing only on analysis of one-dimensional data falls far short of providing an understanding of cancer. Previously, we presented DriverDB, a cancer driver gene database that applies published bioinformatics algorithms to identify driver genes/mutations. The updated DriverDBv3 database (http://ngs.ym.edu.tw/driverdb) is designed to interpret cancer omics' sophisticated information with concise data visualization. To offer diverse insights into molecular dysregulation/dysfunction events, we incorporated computational tools to define CNV and methylation drivers. Further, four new features, CNV, Methylation, Survival, and miRNA, allow users to explore the relations from two perspectives in the 'Cancer' and `Gene' sections. The 'Survival' panel offers not only significant survival genes, but gene pairs synergistic effects determine. A fresh function, 'Survival Analysis' in 'Customized-analysis; allows users to investigate the co-occurring events in user-defined gene(s) by mutation status or by expression in a specific patient group. Moreover, we redesigned the web interface and provided interactive figures to interpret cancer omics' sophisticated information, and also constructed a Summary panel in the 'Cancer' and 'Gene' sections to visualize the features on multi-omics levels concisely. DriverDBv3 seeks to improve the study of integrative cancer omics data by identifying driver genes and contributes to cancer biology.
Abstract Background: The most prevalent type of lung cancer—lung adenocarcinoma—arises from the most distal reaches of the lung in the alveolar epithelium. The alveolar epithelium consists of two cell types: (i) thin type I alveolar epithelial cells (AT1) that facilitate gas exchange and constitute more than 90% of the alveolar surface, and (ii) cuboidal surfactant-producing type II (AT2) cells. Following injury, dynamic interactions between extracellular matrix components, integrins, focal adhesion proteins, and cytoskeletal components allow AT2 progenitor cells to migrate, spread, and transdifferentiate into AT1 cells to restore the denuded epithelial barrier. Methods: Utilizing primary human AT2 cells isolated from lung transplant remnants, our lab has established and extensively profiled an in vitro model of epithelial restitution, wherein AT2 cells differentiate over a period of six days into terminally differentiated AT1-like cells. Because cigarette smoking is the most recognized risk factor for lung adenocarcinoma (LUAD), and because the alveolar space is the primary target of tobacco smoke, we also compared the RNA-seq profiles of AT2>AT1 differentiation to those of A549 LUAD cells exposed to cigarette smoke condensate (CSC). Results: We find that CSC downregulates many factors that are upregulated in the AT2>AT1 restitution model, particularly integrins, extracellular matrix components, and novel focal adhesion proteins that are also downregulated in LUAD relative to adjacent normal tissue. We describe regulation of four such novel focal adhesion proteins, specifically by TGF-β and aryl hydrocarbon receptor (AhR)-mediated mechanisms. Conclusions: Our findings shed light on early mechanisms in the carcinogenic process, and support the notion that alveolar cells engaged in repeated cycles of injury and repair are critical actors in LUAD risk trajectories. Note: This abstract was not presented at the conference. Citation Format: Theresa Ryan Stueve, Chenchen Yang, Crystal N. Marconett, Chunli Yan, Beiyun Zhou, Zea Borok, Ite A. Laird-Offringa. Tobacco smoke increases lung adenocarcinoma risk by downregulating TGF-beta and AhR-regulated focal adhesion proteins involved in injury resolution [abstract]. In: Proceedings of the Fifth AACR-IASLC International Joint Conference: Lung Cancer Translational Science from the Bench to the Clinic; Jan 8-11, 2018; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(17_Suppl):Abstract nr A37.
Homeobox (HOX) genes encode a family of transcription factors, which play crucial roles in numerous processes, and their dysregulation is involved in the carcinogenesis of many human cancers. In the present study, we investigated the roles of HOXC8 in non-small cell lung cancer (NSCLC). We showed that HOXC8 was upregulated in clinical NSCLC specimens compared to normal lung tissues, and the high expression of HOXC8 correlated with tumor node metastasis (TNM) stage, tumor status, lymph nodal status and poor relapse-free survival for lung cancer patients. Functionally, HOXC8 expression significantly promoted the proliferation, anchorage-independent growth and migration of NSCLC, and HOXC8 functioned as a transcription activator to induce the expression of TGFβ1, leading to an increase in the proliferation, anchorage-independent growth and migration of NSCLC. Furthermore, we demonstrated that HOXC8 expression was associated with chemoresistance and anti-apoptosis in NSCLC, suggesting that HOXC8 is a promising therapeutic target for chemosensitization of NSCLC to cisplatin. Altogether, our study defined a critical role of HOXC8 in promoting transcription of TGFβ1 and NSCLC tumorigenesis.
Claudins, the integral tight junction (TJ) proteins that regulate paracellular permeability and cell polarity, are frequently dysregulated in cancer; however, their role in neoplastic progression is unclear. Here, we demonstrated that knockout of Cldn18, a claudin family member highly expressed in lung alveolar epithelium, leads to lung enlargement, parenchymal expansion, increased abundance and proliferation of known distal lung progenitors, the alveolar epithelial type II (AT2) cells, activation of Yes-associated protein (YAP), increased organ size, and tumorigenesis in mice. Inhibition of YAP decreased proliferation and colony-forming efficiency (CFE) of Cldn18-/- AT2 cells and prevented increased lung size, while CLDN18 overexpression decreased YAP nuclear localization, cell proliferation, CFE, and YAP transcriptional activity. CLDN18 and YAP interacted and colocalized at cell-cell contacts, while loss of CLDN18 decreased YAP interaction with Hippo kinases p-LATS1/2. Additionally, Cldn18-/- mice had increased propensity to develop lung adenocarcinomas (LuAd) with age, and human LuAd showed stage-dependent reduction of CLDN18.1. These results establish CLDN18 as a regulator of YAP activity that serves to restrict organ size, progenitor cell proliferation, and tumorigenesis, and suggest a mechanism whereby TJ disruption may promote progenitor proliferation to enhance repair following injury.
Angular deformities of the lower limbs are common during childhood. In children under 2 years of age, bowleg (genu varum) may represent a normal physiological process. In certain circumstances, pathologic bowlegs result from Blount disease, rickets and other metabolic bone diseases, skeletal dysplasia, asymmetric growth secondary to infection, trauma and neoplasia even in a child without a family history.1
Aim: To identify functional lung adenocarcinoma (LUAD) risk SNPs. Materials & methods: Eighteen validated LUAD risk SNPs (p <= 5 x 10(-8)) and 930 SNPs in high linkage disequilibrium (r(2) > 0.5) were integrated with epigenomic information from primary human alveolar epithelial cells. Enhancer-associated SNPs likely affecting transcription factor-binding sites were predicted. Three SNPs were functionally investigated using luciferase assays, expression quantitative trait loci and cancer-specific expression. Results: Forty-seven SNPs mapped to putative enhancers; 11 located to open chromatin. Of these, seven altered predicted transcription factor-binding motifs. Rs6942067 showed allele-specific luciferase expression and expression quantitative trait loci analysis indicates that it influences expression of DCBLD1, a gene that encodes an unknownmembrane protein and is overexpressed in LUAD. Conclusion: Integration of candidate LUAD risk SNPS with epigenomic marks from normal alveolar epithelium identified numerous candidate functional LUAD risk SNPs including rs6942067, which appears to affect DCBLD1 expression. Data deposition: Data are provided in GEO record GSE84273.
Claudins are a family of transmembrane proteins integral to the structure and function of tight junctions (TJ). Disruption of TJ and alterations in claudin expression are important features of invasive and metastatic cancer cells. Expression of CLDN18.1, the lung-specific isoform of CLDN18, is markedly decreased in lung adenocarcinoma (LuAd). Furthermore, we recently observed that aged Cldn18 -/- mice have increased propensity to develop LuAd. We now demonstrate that CLDN18.1 expression correlates inversely with promoter methylation and with LuAd patient mortality. In addition, when restored in LuAd cells that have lost expression, CLDN18.1 markedly attenuates malignant properties including xenograft tumor growth in vivo as well as cell proliferation, migration, invasion and anchorage-independent colony formation in vitro. Based on high throughput analyses of Cldn18 -/- murine lung alveolar epithelial type II cells, as well as CLDN18.1-repleted human LuAd cells, we hypothesized and subsequently confirmed by Western analysis that CLDN18.1 inhibits insulin-like growth factor-1 receptor (IGF-1R) and AKT phosphorylation. Consistent with recent data in Cldn18 -/- knockout mice, expression of CLDN18.1 in human LuAd cells also decreased expression of transcriptional co-activator with PDZ-binding motif (TAZ) and Yes-associated protein (YAP) and their target genes, contributing to its tumor suppressor activity. Moreover, analysis of LuAd cells in which YAP and/or TAZ are silenced with siRNA suggests that inhibition of TAZ, and possibly YAP, is also involved in CLDN18.1-mediated AKT inactivation. Taken together, these data indicate a tumor suppressor role for CLDN18.1 in LuAd mediated by a regulatory network that encompasses YAP/TAZ, IGF-1R and AKT signaling.
Cadherin 11 (CDH11) expression is detected only in invasive breast cancer cells and aggressive breast cancer specimens. However, little is known about the molecular mechanisms of CDH11 transcriptional regulation. Here, we report that interleukin enhancer binding factor 3 (ILF3) interacts with Homeobox C8 (HOXC8) to activate CDH11 transcription in breast cancer cells. Using co-immunoprecipitation and mass spectrometry analyses, ILF3 is shown to interact with HOXC8 in breast cancer cells. We demonstrate that ILF3 binds to the CDH11 promoter on nucleotides –2982 ~ –2978 and –2602 ~ 2598 and interacts with HOXC8 to co-activate CDH11 transcription. We further show that ILF3 promotes proliferation and migration, at least partially, by facilitating CDH11 expression in breast cancer cells. Moreover, immunohistochemistry (IHC) shows that expression of CDH11, ILF3 and HOXC8 are all upregulated in breast cancer specimens compared to normal breast tissues. Importantly, the expression levels of CDH11, ILF3 and HOXC8 are elevated in the advanced stages of breast cancer, and high expression of CDH11, ILF3 and HOXC8 is associated with poor distant metastasis-free survival (DMFS) for breast cancer patients.
Smoking-associated DNA hypomethylation has been observed in blood cells and linked to lung cancer risk. However, its cause and mechanistic relationship to lung cancer remain unclear. We studied the association between tobacco smoking and epigenome-wide methylation in non-tumor lung (NTL) tissue from 237 lung cancer cases in the Environment And Genetics in Lung cancer Etiology study, using the Infinium HumanMethylation450 BeadChip. We identified seven smoking-associated hypomethylated CpGs (P < 1.0 × 10-7), which were replicated in NTL data from The Cancer Genome Atlas. Five of these loci were previously reported as hypomethylated in smokers' blood, suggesting that blood-based biomarkers can reflect changes in the target tissue for these loci. Four CpGs border sequences carrying aryl hydrocarbon receptor binding sites and enhancer-specific histone modifications in primary alveolar epithelium and A549 lung adenocarcinoma cells. A549 cell exposure to cigarette smoke condensate increased these enhancer marks significantly and stimulated expression of predicted target xenobiotic response-related genes AHRR (P = 1.13 × 10-62) and CYP1B1 (P < 2.49 × 10-61). Expression of both genes was linked to smoking-related transversion mutations in lung tumors. Thus, smoking-associated hypomethylation may be a consequence of enhancer activation, revealing environmentally-induced regulatory elements implicated in lung carcinogenesis.
Claudins are integral tight junction (TJ) proteins that contribute to cell polarity and regulate paracellular permeability to ions and solutes. Claudin 18 (CLDN18) is one of the most highly expressed claudin family members in lung alveolar epithelium. To investigate the role of CLDN18 in alveolar homeostasis, we recently generated Cldn18−/− mice that demonstrate increased lung solute permeability and alveolar fluid clearance (AFC) compared to wild type (WT) controls. Lungs of Cldn18−/− mice are markedly enlarged due to increased abundance and proliferation of alveolar epithelial type II (AT2) cells, known progenitors of distal lung epithelium, with resultant parenchymal expansion. Cldn18−/− AT2 cells grown with MLg fibroblasts in 3‐dimensional (3D) culture show increased colony forming efficiency (CFE), suggesting increased progenitor capacity. Given its known role in regulating stem/progenitor cell proliferation and organ size, we investigated a potential role for Yes‐associated protein (YAP) signaling in mediating the proliferative phenotype of Cldn18−/− lung progenitors. Progenitor cell activation was accompanied by activation of YAP, as evidenced by increased nuclear YAP, increased expression of YAP target genes in lungs of Cldn18−/− mice, and increased YAP and decreased phospho‐YAP (p‐YAP) by western analysis in isolated Cldn18−/− AT2 cells and by immunofluorescence in Cldn18−/− AT2 cells in 3D culture. Treatment with the YAP inhibitor verteporfin (VP, 100 mg/kg) reduced AT2 cell proliferation in vivo (EdU+NKX2.1+/total cells: 1.36 ± 0.10% vehicle vs 0.93 ± 0.06% VP, p<0.05) and decreased lung size (lung dry weight/body weight ratios (mg/g): 3.56 ± 0.08 vehicle vs 2.93 ± 0.13 VP, p<0.05) in Cldn18−/− mice. Inhibition of YAP with VP (0.75 μM) or shRNA decreased colony size (~50% vs control) and number (30–50% vs control) and reduced proliferation (Ki67+ cells at 10.7 ± 0.4% VP vs 29.2 ± 3.7% vehicle) of Cldn18−/− AT2 cells in 3D culture, while overexpression of CLDN18 decreased YAP nuclear localization, cell proliferation, CFE and YAP activity. These results reveal a novel role for YAP signaling in regulation of distal lung epithelial progenitor cell homeostasis and identify a role for TJ proteins, in particular CLDN18, in regulating YAP activity and organ size. Overall, they suggest a mechanism whereby growth‐promoting signals are transduced from TJ to the nucleus that has important implications for modulating stem/progenitor cell function and regeneration following injury.Support or Funding InformationNational Institutes of Health, Hastings and Whittier Foundations
Epidemiologically related traits may share genetic risk factors, and pleiotropic analysis could identify individual loci associated with these traits. Because of their shared epidemiological associations, we conducted pleiotropic analysis of genome-wide association studies of lung cancer (12 160 lung cancer case patients and 16 838 control subjects) and cardiovascular disease risk factors (blood lipids from 188 577 subjects, type 2 diabetes from 148 821 subjects, body mass index from 123 865 subjects, and smoking phenotypes from 74 053 subjects). We found that 6p22.1 (rs6904596, ZNF184) was associated with both lung cancer (P = 5.50x10(-6)) and blood triglycerides (P = 1.39x10(-5)). We replicated the association in 6097 lung cancer case patients and 204 657 control subjects (P = 2.40 × 10(-4)) and in 71 113 subjects with triglycerides data (P = .01). rs6904596 reached genome-wide significance in lung cancer meta-analysis (odds ratio = 1.15, 95% confidence interval = 1.10 to 1.21 ,: Pcombined = 5.20x10(-9)). The large sample size provided by the lipid GWAS data and the shared genetic risk factors between the two traits contributed to the uncovering of a hitherto unidentified genetic locus for lung cancer.