Pathway In Non-small Cell Lung Cancer Research Articles

The Pharmacogenomics "Side-effect" of TP53/EGFR in Non-small Cell Lung Cancer Accompanied with Atorvastatin Therapy: A Functional Network Analysis.

Atorvastatin belongs to the group of statins and is the leading drug for hypercholesterolemia treatment. Although, its anticancer effects are highly appreciated, its properties are still unclear. The aim of this study was to explore the underlying anticancer mechanisms induced by atorvastatin and enlarge the potential target in non-small cell lung cancer. Target genes of atorvastatin were collected by the DrugBank database. Prediction of interaction between primary targets and secondary targets was performed, and protein-protein interaction network was constructed though the STRING. Then, KEGG pathway enrichment analysis was performed with WebGestalt and ClueGO, including the pathways in non-small cell lung cancer. Furthermore, a genomic alteration analysis of the selected seed genes of atorvastatin benefit and non-small cell lung cancer pathway was conducted by cBioPortal. Finally, a survival analysis with the selected seed genes in lung cancer (lung adenocarcinoma, lung squamous cell carcinoma) was conducted using Kaplan-Meier (KM) plotter. To identify seed genes, 65 potential candidate genes were screened as targets for atorvastatin using STRING with DrugBank database, while the KEGG pathway was enriched to get the overlap match of pathways in non-small cell lung cancer. Then 4 seed genes, Epidermal Growth Factor Receptor (EGFR), erb-b2 receptor tyrosine kinase 2 (ERBB2), AKT serine/threonine kinase 1 (AKT1) and tumor protein p53 (TP53), were selected and their genomic alternation were evaluated by cBioPortal. Survival analysis found that TP53 and EGFR showed a significant correlation (log rank P = 3e-07 and 0.023) with lung adenocarcinoma and lung squamous cell carcinoma, according to the KM analysis. Gene-phenotype connectivity for atorvastatin in non-small cell lung cancer was identified using functional/activity network analysis method, and our findings demonstrated that TP53 and EGFR could be the potential targets in cancer patients with atorvastatin therapy.

MiR-323-3p Targeting Transmembrane Protein with EGF-Like and 2 Follistatin Domain (TMEFF2) Inhibits Human Lung Cancer A549 Cell Apoptosis by Regulation of AKT and ERK Signaling Pathways.

BackgroundNon-small-cell lung cancer (NSCLC) is predominant and has low 5-year relative survival rate. Therefore, the mechanisms of NSCLC tumorigenesis must be comprehensively elucidated. MicroRNA-323-3p (miR-323-3p) has been widely explored and found to exert functions in tumorigenesis of several cancer types. However, the expression pattern and biological function of miR-323-3p and the molecular mechanism underlying NSCLC development and progression remain unclear.Material/MethodsQuantitative reverse-transcription polymerase chain reaction was used to detect the expression of miR-323-3p and TMEFF2 in NSCLC cell lines (A549, NCI-H3255, and H1299) and normal cell line (BEAS-2B). Methylthiazolyl tetrazolium, colony formation, and flow cytometry assays were performed to evaluate the effects of miR-323-3p and TMEFF2 on cell proliferation. Transwell assay was conducted to determine the effects of TMEFF2 on cell migration and invasion. Dual-luciferase reporter assay was used to verify whether TMEFF2 is a target of miR-323-3p. Western blot analysis was performed to analyze protein expression.ResultsThe expression of miR-323-3p increased in the 3 NSCLC cell lines (A549, NCI-H3255, and H1299). miR-323-3p regulated cellular progression by directly suppressing TMEFF2 expression and indirectly prohibited the activation of AKT and ERK pathways in NSCLC.ConclusionsOverall, miR-323-3p was considered a lung cancer oncogene and could be a valuable target for NSCLC therapy.

MicroRNA-103a Curtails the Stemness of Non-Small Cell Lung Cancer Cells by Binding OTUB1 via the Hippo Signaling Pathway.

Objective:Although microRNA-103a (miR-103a) dysfunction has been implicated in various cancers, its relevance to non-small cell lung cancer (NSCLC) has not been clarified. This study was conducted to examine the molecular mechanism underlying the regulatory role of miR-103a in NSCLC.Methods:Kaplan–Meier analysis was carried out to assess the relationship between overall survival of NSCLC patients and miR-103a expression. Reverse-transcription quantitative polymerase chain reaction and western blot analyses were applied to evaluate the expression of relevant genes in tissues and cells. Sphere formation, MTS, flow cytometry, and Transwell assays were performed to characterize stemness. Dual luciferase reporter gene assays were used to clarify the binding relationship between miR-103a and ovarian tumor domain-containing ubiquitin aldehyde binding protein 1 (OTUB1). Finally, western blot analysis was used to assess the involvement of the Hippo pathway in NSCLC.Results:In NSCLC tissues and cells, miR-103a was expressed at low levels, whereas OTUB1 was expressed at high levels. Higher miR-103 expression levels were associated with a better prognosis for patients with NSCLC. When miR-103a was overexpressed, cell viability and stemness decreased, whereas apoptosis and cell cycle arrest were facilitated. The expression of phosphorylated YAP also decreased significantly. Opposite trends were observed after miR-103a silencing. OTUB1 expression and YAP phosphorylation decreased in the presence of miR-103a, and OTUB1 overexpression blocked the inhibitory effects of miR-103a on NSCLC cells.Conclusion:The miR-103a/OTUB1/Hippo axis may play a role in modulating the malignant behavior and stemness of cancer stem cells and thus could be a potential therapeutic target for the management of NSCLC.

MicroRNA-629 promotes the tumorigenesis of non-small-cell lung cancer by targeting FOXO1 and activating PI3K/AKT pathway.

MicroRNA-629 (miR-629) has been found to play an important role in the pathogenesis of human cancers. However, the function of miR-629 is still unknown in non-small-cell lung cancer (NSCLC). The purpose of this study is to preliminarily elucidate the regulatory mechanism of miR-629 in NSCLC. The mRNA and protein expression was measured by real-time quantitative polymerase chain reaction (RT-qPCR) and western blot analysis. The function of miR-629 was investigated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) and Transwell assays. The relationship between miR-629 and FOXO1 was confirmed by dual luciferase assay. MiR-629 was upregulated in NSCLC tissues and cells. High expression of miR-629 predicted poor prognosis in patients with NSCLC. Moreover, miR-629 promoted cell proliferation, migration and invasion in NSCLC cells. In addition, FOXO1 was confirmed as a direct target of miR-629 in NSCLC. Furthermore, knockdown of FOXO1 also promoted proliferation, migration and invasion of NSCLC cells. More importantly, overexpression of FOXO1 weakened the carcinogenesis of miR-629 in NSCLC. Besides that, miR-629 promoted EMT and activated the PI3K/AKT pathway in NSCLC. MiR-629 promotes the progression of NSCLC by targeting FOXO1 and regulating EMT/PI3K/AKT pathway.

Aberrantly High Expression Of NOK/STYK1 Is Tightly Associated With The Activation Of The AKT/GSK3β/N-Cadherin Pathway In Non-Small Cell Lung Cancer.

PurposeHigh metastasis is a leading risk factor for the survival of non-small cell lung cancer (NSCLC) and epithelial-mesenchymal transition (EMT) is a vital step of metastasis. The expression of novel oncogene with kinase domain (NOK) has been observed in some human malignancies, including non-small cell lung cancer (NSCLC); however, the biological function of NOK in NSCLC remains unclear. In the study, we explored the function of NOK in NSCLC, with an aim to elucidate the relevant underlying mechanisms.Patients and methodsWe investigate the expression of NOK, p-Akt, p-GSK-3β, E-cadherin and N-cadherin expression by immunohistochemical analysis using tissue microarrays of 72 paired NSCLC samples of cancerous and adjacent normal tissues. The associations between NOK expression and clinicopathological factors, overall survival, other proteins were assessed. Immunofluorescence analysis of NSCLC tissues was performed to study the location of NOK, Akt and GSK-3β. Up or down-regulated of NOK were conducted in two NSCLC cell lines to analyze its impact on AKT/GSK3β pathway.ResultsStatistical analysis revealed NOK expression increased in NSCLC tissues compared with normal tissues (P<0.05). It also showed that low NOK expression were associated with a higher possibility of non-lymphatic metastasis, an early pN stage and clinical stage (P<0.05). Moreover, NOK expression was positively correlated with the expression of oncogene p-Akt (Thr308), p-GSK-3β (Ser9) and N-cadherin (P<0.05). Immunofluorescence analysis of NSCLC tissues revealed that NOK is co-located with Akt and GSK-3β. Further study in NSCLC cell lines revealed that NOK overexpression can activate the AKT/GSK3β pathway. Conversely, knockdown of NOK can suppress the AKT/GSK3β pathway.ConclusionOur results suggest that NOK overexpression correlated significantly with lymphatic metastasis, advanced pN and clinical stage in NSCLC. And NOK may promote EMT by activating the AKT/GSK3β/N-cadherin pathway in NSCLC.

FGFR1 Induces Acquired Resistance Against Gefitinib By Activating AKT/mTOR Pathway In NSCLC.

ObjectiveAs an epidermal growth factor, receptor-tyrosine kinase inhibitor (EGFR-TKI), gefitinib demonstrates a good therapeutic effect in patients with EGFR-mutant non-small-cell lung cancer (NSCLC). However, an overwhelming majority of these patients inevitably develop resistance against gefitinib. Unfortunately, the mechanism underlying this phenomenon is still not fully understood. Here we aim to reveal the mechanism of gefitinib resistance in NSCLC induced by FGFR1.Materials and methodsWe used high-throughput sequencing to compare the mRNA expression profiles of PC9 and PC9-GR (gefitinib-resistant) cells. The clinical significance of fibroblast growth factor receptor 1 (FGFR1) in NSCLC was also investigated using immunohistochemistry and Kaplan-Meier survival analysis. Finally, the in vitro molecular mechanisms were analyzed using confocal laser microscopy, Western blotting, transwell assay, colony formation assay, CCK-8 assay, and apoptosis assay.ResultsWe observed that FGFR1 was highly expressed in NSCLC tissues and was closely associated with poor prognosis. Cytological experiments showed that FGFR1 promoted the proliferation and migration of PC9-GR cells and mediated their resistance to gefitinib. Furthermore, studies aimed at unraveling this mechanism revealed that FGFR1 activated the AKT/mTOR signaling pathway. These findings show that the FGFR1/AKT/mTOR signaling pathway plays a vital role in acquired resistance against gefitinib in NSCLC.ConclusionThis work provides new evidence that FGFR1 functions as a key regulator of gefitinib resistance, thereby demonstrating its potential as a novel biomarker and therapeutic target for NSCLC.

Osteopontin Mediates Cetuximab Resistance via the MAPK Pathway in NSCLC Cells.

BackgroundNon-small cell lung cancer (NSCLC) is the most common type of lung cancer. The high expression of osteopontin (OPN) is an important factor that aggravates drug resistance and causes a poor prognosis in this disease. Therefore, understanding the molecular mechanism of OPN is critical for the treatment and prognosis of NSCLC.MethodsWe used bioinformatics analysis to verify the expression of OPN in normal lung tissues and lung cancer tissues. Then we overexpressed and knocked down OPN in cell lines to detect cell proliferation, migration, invasion, and effects on signaling pathways. Finally, malignant progression and drug resistance induced by OPN were investigated by the wound healing assay, transwell assay, clone formation assay, and Western blot analysis.ResultsWe verified that OPN was upregulated in NSCLC tissues, and its overexpression induced NSCLC cell proliferation, migration, and invasion via the mitogen-activated protein kinase (MAPK) pathway. Furthermore, overexpression of OPN reduced the sensitivity of NSCLC cells to cetuximab by upregulating MAPK pathway-related proteins. These results suggested that OPN promoted malignant progression and mediated drug resistance via the MAPK signaling pathway in NSCLC cells.ConclusionThis study reveals the important role of OPN in NSCLC cells, making it a potential target for improving chemotherapy efficiency in patients with NSCLC.

Expression Of Intracellular Components of the NF-\u03baB Alternative Pathway (NF-\u03baB2, RelB, NIK and Bcl3) is Associated With Clinical Outcome of NSCLC Patients

A growing number of studies has shed light on the role of the NF-κΒ in non-small-cell lung cancer (NSCLC). To address the significance of major effectors of the NF-κΒ alternative pathway, we investigated the relationship between NF-κΒ2, RelB, NIK and Bcl3 expression (mRNA and protein) and the clinical outcome of NSCLC patients. NF-κΒ2, RelB, NIK and Bcl3 protein expression levels were assessed by immunohistochemistry in tissue samples from 151 NSCLC patients who had curative resection. mRNA levels were also evaluated in 69 patients using quantitative real-time PCR. Although all studied proteins were overexpressed in NSCLC (P < 0.001 for all), only RelB mRNA levels were strongly increased in cancerous specimens compared to tumor-adjacent non-neoplastic tissues (P = 0.009). Moreover, NF-κB2, RelB and Bcl3 expression was associated with overall survival (OS). In particular, cytoplasmic and mRNA expression of RelB was related to 5-year OS (P = 0.014 and P = 0.006, respectively). Multivariate analysis also showed that Bcl3 expression (nuclear and cytoplasmic) was associated with increased 5-year OS (P = 0.002 and P = 0.036, respectively). In addition, higher Bcl3 mRNA levels were associated with inferior OS in stages I & II and improved OS in stages III and IV after 5-year follow-up (P = 0.004 and P = 0.001, respectively). Furthermore, stage I patients with lower NF-κB2 mRNA levels had better 5-year survival in univariate and multivariate analysis (P = 0.031 and P = 0.028, respectively). Interestingly, RelB expression (cytoplasmic and mRNA) was inversely associated with relapse rates (P = 0.027 and P = 0.015, respectively), while low NIK cytoplasmic expression was associated with lower relapse rates (P = 0.019). Cytoplasmic NIK expression as well as NF-κB2/ Bcl3 detection was associated with lymph node infiltration (P = 0.039 and P = 0.014, respectively). The present study confirms the deregulation of the NF-κB alternative pathway in NSCLC and also demonstrates the importance of this pathway in prognosis, recurrence and infiltration of regional lymph nodes.

Metabolomic, transcriptomic and genetic integrative analysis reveals important roles of adenosine diphosphate in haemostasis and platelet activation in non‐small‐cell lung cancer

Lung cancer is the leading cause of cancer‐related deaths in the world. The most prevalent subtype, accounting for 85% of cases, is non‐small‐cell lung cancer (NSCLC). Lung squamous cell carcinoma (LUSC) and lung adenocarcinoma (LUAD) are the most common subtypes. Despite recent advances in treatment, the low 5‐year survival rate of NSCLC patients (approximately 13%) reflects the lack of early diagnostic biomarkers and incomplete understanding of the underlying disease mechanisms. We hypothesized that integration of metabolomic, transcriptomic and genetic profiles of tumours and matched normal tissues could help to identify important factors and potential therapeutic targets that contribute to tumorigenesis. We integrated omics profiles in tumours and matched adjacent normal tissues of patients with LUSC (N = 20) and LUAD (N = 17) using multiple system biology approaches. We confirmed the presence of previously described metabolic pathways in NSCLC, particularly those mediating the Warburg effect. In addition, through our combined omics analyses we found that metabolites and genes that contribute to haemostasis, angiogenesis, platelet activation and cell proliferation were predominant in both subtypes of NSCLC. The important roles of adenosine diphosphate in promoting cancer metastasis through platelet activation and angiogenesis suggest this metabolite could be a potential therapeutic target.

Design, synthesis and biological evaluation of some new 1,3,4-thiadiazine-thiourea derivatives as potential antitumor agents against non-small cell lung cancer cells

New 1,3,4-thiadiazine-thiourea derivatives have been synthesized. All the synthesized compounds were examined for in vitro cytotoxic activity against Non-Small Cell Lung Cancer (NSCLC) cell line A549, using MTT bioassay. Compounds 5d, 5i, 5j showed the highest cytotoxic activity with IC50 values of 0.27 ± 0.01, 0.30 ± 0.02, and 0.32 ± 0.012 μM respectively with sorafenib as reference (IC50 3.85 ± 0.27 μM). These compounds were chosen for further investigations against various biological targets known to play roles in NSCLC specifically: vascular endothelial growth factor receptor 2 (VEGFR2), B-RAF and matrix metalloproteinase 9 (MMP9). Encouraging results were exhibited by the three compounds against the selected targets. Compound 5j was specially promising as it exhibited inhibitory activity of VEGFR2 close to sorafenib (IC50 0.11 ± 0.01 μM), most potent B-RAF activity inhibition (IC50 0.178 ± 0.004 μM) and MMP9 inhibition (IC50 0.08 ± 0.004 μM). Moreover, cell cycle analysis of A549 cells treated with 5j exhibited cell cycle arrest at G2-M phase and pro-apoptotic activity as indicated by Annexin V-FITC staining. Also, it reflected antinvasive and antimigration properties to A549 cells. Additionally, docking study of 5j on VEGFR2, B-RAF and MMP9 revealed that it binds to the target enzymes in a similar way as the co-crystallized ligand. The three compounds exhibited significantly high selectivity to A549 cancer cells against the normal human fetal lung fibroblast cell line WI-38 with higher selectivity index compared to sorafenib (5d IC50 136.76 ± 2.38 μM, SI = 506.52; 5i IC50 89.20 ± 2.11 μM, SI = 297.33; 5j IC50 79.60 ± 3.8 μM, SI = 248.75; sorafenib IC50 30.32 ± 2.41 μM, SI = 7.88). In conclusion, compounds 5d, 5i and 5j, specially 5j are promising anticancer agents targeting important pathways in NSCLC and warrant further preclinical and clinical trials.

Estrogen receptors promote NSCLC progression by modulating the membrane receptor signaling network: a systems biology perspective

BackgroundEstrogen receptors (ERs) are thought to play an important role in non-small cell lung cancer (NSCLC). However, the effect of ERs in NSCLC is still controversial and needs further investigation. A new consideration is that ERs may affect NSCLC progression through complicated molecular signaling networks rather than individual targets. Therefore, this study aims to explore the effect of ERs in NSCLC from the perspective of cancer systems biology.MethodsThe gene expression profile of NSCLC samples in TCGA dataset was analyzed by bioinformatics method. Variations of cell behaviors and protein expression were detected in vitro. The kinetic process of molecular signaling network was illustrated by a systemic computational model. At last, immunohistochemical (IHC) and survival analysis was applied to evaluate the clinical relevance and prognostic effect of key receptors in NSCLC.ResultsBioinformatics analysis revealed that ERs might affect many cancer-related molecular events and pathways in NSCLC, particularly membrane receptor activation and signal transduction, which might ultimately lead to changes in cell behaviors. Experimental results confirmed that ERs could regulate cell behaviors including cell proliferation, apoptosis, invasion and migration; ERs also regulated the expression or activation of key members in membrane receptor signaling pathways such as epidermal growth factor receptor (EGFR), Notch1 and Glycogen synthase kinase-3β/β-Catenin (GSK3β/β-Catenin) pathways. Modeling results illustrated that the promotive effect of ERs in NSCLC was implemented by modulating the signaling network composed of EGFR, Notch1 and GSK3β/β-Catenin pathways; ERs maintained and enhanced the output of oncogenic signals by adding redundant and positive-feedback paths into the network. IHC results echoed that high expression of ERs, EGFR and Notch1 had a synergistic effect on poor prognosis of advanced NSCLC.ConclusionsThis study indicated that ERs were likely to promote NSCLC progression by modulating the integrated membrane receptor signaling network composed of EGFR, Notch1 and GSK3β/β-Catenin pathways and then affecting tumor cell behaviors. It also complemented the molecular mechanisms underlying the progression of NSCLC and provided new opportunities for optimizing therapeutic scheme of NSCLC.

LncRNA NBR2 inhibits EMT progression by regulating Notch1 pathway in NSCLC.

The aim of this study was to identify the role of long non-coding RNA (lncRNA) NBR2 in non-small-cell lung cancer (NSCLC) and its possible molecular mechanisms. The quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was used to explore lncRNA NBR2 expression in NSCLC cells and tissues. The chi-square test was used to analyze the relationship between lncRNA NBR2 expression and the clinical features of NSCLC patients. The pcDNA3.1 and pcDNA3.1-NBR2 vectors were transfected into NSCLC cells, and the proliferation and migration ability of NSCLC cells were detected using cell counting kit-8 (CCK-8) and transwell assay. The epithelial-mesenchymal transition (EMT)-related genes expression was detected by an EMT RT2 PCR array. QRT-PCR and Western blot was used to analyze the mRNA and protein levels of Notch1, Vimentin, N-cadherin, E-cadherin, HEY1, HEY2, and HEYL. The expression of lncRNA NBR2 was decreased in NSCLC patients tissues, and the NSCLC patients in the NBR2 low expression group showed a poor prognosis. Meanwhile, the expression of NBR2 in patients with NSCLC was correlated with tumor size. Overexpression of NBR2 suppressed the viability and migration of NSCLC cells and the expression of Notch1 and EMT-related genes in AsPC-1 cells. Simultaneous overexpression of NBR2 and Notch1 could reverse the inhibitory effect of NBR2 on proliferation and migration of NSCLC cells. LncRNA NBR2 inhibited the progression of EMT in NSCLC by regulating the Notch1 pathway.

FAM83A signaling induces epithelial-mesenchymal transition by the PI3K/AKT/Snail pathway in NSCLC.

Family with sequence similarity 83, member A (FAM83A), as a potential tumor promoter, was reported to contribute to the progression of several malignant tumors. However, the significance of FAM83A in invasion and metastasis of non-small cell lung cancer (NSCLC) remains largely unknown. In this study, we found that FAM83A expression was significantly increased in NSCLC tissues. High expression of FAM83A was positively associated with tumor metastasis and poor survival of NSCLC patients. Functional experiments revealed that FAM83A knockdown could suppress NSCLC cell migration and invasion both in vivo and in vitro. While opposite results were observed in FAM83A-transfected cells. Mechanically, we found that FAM83A promoted NSCLC cell migration and invasion by inducing epithelial-mesenchymal transition (EMT) via PI3K/ATK/Snail signaling. Rescue experiment demonstrated that inhibition of either AKT or Snail could partially counteract the promoting effect of FAM83A overexpression in NSCLC metastasis. Taken together, our findings are the first time to demonstrate that increased expression of FAM83A in NSCLC was correlated with EMT and tumor metastasis, which may provide a novel therapeutic target in NSCLC treatment.

MicroRNA‑208a directly targets Src kinase signaling inhibitor 1 to facilitate cell proliferation and invasion in non‑small cell lung cancer.

The abnormal expression of microRNAs (miRNAs/miRs) has a critical function in the formation and progression of non-small cell lung cancer (NSCLC). Therefore, understanding the association between NSCLC and dysregulated miRNAs may allow for the identification of novel diagnostic and therapeutic biomarkers for patients with this malignancy. Previous studies have validated miR-208a as a cancer-associated miRNA in multiple different types of human cancer, however, its expression pattern and precise function in NSCLC remains yet to be elucidated. Therefore, the aims of the present study were to measure miR-208a expression in NSCLC, investigate its specific functions in NSCLC and determine its exact regulatory mechanisms. Herein, the results demonstrated that miR-208a was significantly upregulated in NSCLC tissues and cell lines compared with that in adjacent non-cancerous tissues and a non-tumorigenic bronchial epithelium BEAS-2B cell line (P<0.05, respectively). The high expression level of miR-208a exhibited an obvious association with Tumor-Node-Metastasis stage and lymph node metastasis. miR-208a silencing decreased the proliferative and invasive capacities of NSCLC cells. Notably, Src kinase signaling inhibitor 1 (SRCIN1) was verified as a potential direct target gene of miR-208a in NSCLC cells. Furthermore, SRCIN1 knockdown was able to rescue the miR-208a-mediated effects on NSCLC cells. In addition to this, silencing miR-208a expression inhibited the extracellular regulated kinase (ERK) signaling pathway in NSCLC. Overall, to the best of our knowledge, the present study is the first to provide evidence that miR-208a exerts oncogenic functions in the carcinogenesis and progression of NSCLC by directly targeting SRCIN1 and regulating the ERK pathway. Therefore, miR-208a may be developed as a potential target for treating patients with NSCLC.

SRC and MEK Co-inhibition Synergistically Enhances the Anti-tumor Effect in Both Non-small-cell Lung Cancer (NSCLC) and Erlotinib-Resistant NSCLC

Non-small-cell lung cancer (NSCLC) is the predominant form of lung cancer, and it is regulated by a complex signal transduction network. Single-agent targeted therapy often results in acquired resistance, which leads to treatment failure. In this study, we demonstrated that a combination of the kinase inhibitors trametinib and bosutinib can synergistically suppress the growth of NSCLC by inhibiting both the mitogen-activated protein kinase (MAPK) and proto-oncogene tyrosine-protein kinase (SRC) pathways. The combination was profiled against a panel of 22 NSCLC cell lines, including one erlotinib-resistant cell line, and this combination was found to show synergistic effects against 16 cell lines. NSCLC cell lines (HCC827, HCC827-erlotinib-resistant, and H1650) were treated with trametinib, bosutinib, or a combination of these drugs. The drug combination inhibited colony formation and induced cell apoptosis. A mechanism study showed that the phosphorylation of multiple kinases in the epidermal growth factor receptor (EGFR) signaling pathway in NSCLC was down-regulated. In addition, the combination significantly attenuated tumor growth of HCC827 xenografts with low toxicity. Our findings provide a theoretical basis for further study of the combination of MAPK and SRC pathway inhibitors in NSCLC, especially in the treatment of erlotinib-resistant NSCLC.

The estrogen pathway as a modulator of response to immunotherapy.

Lung cancer is the leading cause of cancer deaths worldwide, with a 5-year survival rate of about 18%. Thus, there is a great need for novel therapeutic approaches to treat non-small-cell lung cancer (NSCLC). Immune checkpoint inhibitors (ICIs) have improved outcomes for a subset of patients, especially those with high programmed death-ligand 1 expression and/or high tumor mutational burden, but have failed in the majority of patients. Increasing evidence suggests that the estrogen signaling pathway may be a therapeutic target in metastatic NSCLC and that the estrogen pathway may play a role in sex-based responses to ICIs. This report will review the epidemiologic, preclinical and clinical data on the estrogen pathway in NSCLC, its implications in sex-based responses to ICIs and the potential use of antiestrogen therapy in combination with ICIs.

PVT1 Promotes Angiogenesis by Regulating miR-29c/Vascular Endothelial Growth Factor (VEGF) Signaling Pathway in Non-Small-Cell Lung Cancer (NSCLC).

BackgroundLung cancer is a common tumor. Non-small-cell lung cancer (NSCLC) accounts for over 85% of lung cancer and has a high degree of malignancy. Angiogenesis plays an important role in NSCLC progression. Some studies have found that PVT1 can promote angiogenesis in tumor tissues, but the role of PVT1 in angiogenesis in NSCLC, as well as the underlying mechanism, is unclear.Material/MethodsTo explore the role of PVT1 in NSCLC, qRT-PCR, Western blot, luciferase reporter assay, and ELISA were carried out for detecting the relationship among PVT1, miR-29c, and VEGF. Tube formation assay was used to assess the role of PVT1 in angiogenesis in NSCLC.ResultsOur results showed that higher PVT1 was expressed in NSCLC and the elevated PVT1 was closely related to angiogenesis and poor prognosis in NSCLC. Further functional analysis showed that higher PVT1 expression could promote angiogenesis by regulating VEGF in NSCLC. Mechanistically, the luciferase reporter assay confirmed that VEGF was the targeted gene of miR-29c. In addition, we found that miR-29c is an inhibitory target of PVT1.ConclusionsWe found that PVT1 promotes angiogenesis through targeting the miR-29c/VEGF signaling pathway in NSCLC.

Abstract 4656: TRAF1 is critical for regulating the BRAF/MEK/ERK pathway in non-small cell lung carcinogenesis

Abstract Tumor necrosis factor receptor (TNFR)-associated factor 1 (TRAF1) is a unique TRAF protein that can interact directly or indirectly with multiple TNFR family members, regulatory proteins, kinases, and adaptors that contribute to its diverse functions in specific tissues. However, the role of TRAF1 in non-small cell lung cancer (NSCLC) remains unknown. In this study, we report that TRAF1 is overexpressed in human lung cancer cells and tissues. TRAF1 expression level inversely correlated with patient survival probability. Loss of TRAF1 decelerated tumor invasion in a urethane-induced lung carcinogenesis mouse model. Furthermore, TRAF1 expression affected TRAF2-mediated BRAF Lys48-linked ubiquitination, which was followed by the inhibition of growth and differentiation, and the induction of death in lung cancer cells. Overall, our work suggests that TRAF1 plays a novel role in the regulation of the BRAF/MEK/ERK signaling pathway in NSCLC and offers a candidate molecular target for lung cancer prevention and therapy. Citation Format: Qiushi Wang, Tianshun Zhang, Ge Gao, Ann Bode, Zigang Dong. TRAF1 is critical for regulating the BRAF/MEK/ERK pathway in non-small cell lung carcinogenesis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4656.

EGCG overcomes gefitinib resistance by inhibiting autophagy and augmenting cell death through targeting ERK phosphorylation in NSCLC.

BackgroundSeveral EGFR-tyrosine kinase inhibitors (TKIs), such as gefitinib (Gef), have been used as effective clinical therapies for patients with non-small cell lung cancer (NSCLC). However, due to acquired resistance, the efficacy of Gef treatment is severely blocked. Our preliminary study found that epigallocatechin gallate (EGCG) in combination with Gef could work synergistically to increase the sensitivity to Gef in NSCLC, but the mechanisms responsible for this have not been completely defined.PurposeIn our present study, we devoted to investigate the synergistic effects of combined EGCG and Gef treatment and the importance of autophagy and ERK signaling pathway in overcoming acquired drug resistance to Gef in NSCLC.MethodsWe evaluated the synergistic effects of combined EGCG and Gef treatment through in vitro cell proliferation/viability assays and in vivo xenograft studies, respectively. Autophagic flux was assessed by GFP-microtubule-associated protein 1 light chain 3 (LC3) plasmid transfection and western blot detection of autophagy-related proteins. Besides, the role of ERK on acquired resistance was validated with a ERK inhibitor.ResultsWe discovered that EGCG can synergize with Gef to inhibit the proliferation of Gef-resistant NSCLC cells and suppress tumor growth in a xenograft mouse model. The underlying mechanisms of synergism were investigated, and the results showed that co-treatment with Gef and EGCG could inhibit Gef-induced autophagy and ERK phosphorylation. Consistently, the expression of LC3-II/I and ATG5 were inhibited, whereas the expression of p62 was enhanced in EGCG and Gef combination treatment groups. Further, inhibition of autophagy in Gef-resistant A549 cells could augment cell death.ConclusionIn conclusion, EGCG overcomes Gef resistance by inhibiting autophagy and augmenting cell death through targeting ERK pathway in NSCLC. Gef and EGCG combination therapy may be an effective strategy to overcome acquired resistance in NSCLC.

Apoptosis induction and AKT/NF-κB inactivation are associated with regroafenib-inhibited tumor progression in non-small cell lung cancer in vitro and in vivo

Non-small cell lung cancer (NSCLC) is a malignant lung cancer type with poor prognosis. NF-κB, the oncogenic transcription factor, has been recognized as an important mediator in progression of NSCLC. Regorafenib, a multikinase inhibitor, was demonstrated to inhibit tumor progression through suppression of ERK/NF-κB signaling in hepatocellular carcinoma cells in vitro and in vivo. However, whether regorafenib inhibit progression of NSCLC is ambiguous. Thus, the major purpose of present study was to evaluate anticancer efficacy and underlying mechanism of regorafenib on tumor progression in NSCLC in vitro and in vivo. CL-1-5-F4 cells were treated with regorafenib, NF-κB (QNZ) or AKT (LY294002) inhibitor for 24 or 48 h. Then, we performed cell viability assay, NF-κB reporter gene assay, transwell invasion assay and apoptosis related flow cytometry assay on cellular level to verify anti-cancer effect and mechanism of regorafenib. CL-1-5-F4 bearing animal model was treated with vehicle or regorafenib for 28 days. The therapeutic efficacy and mechanism of regorafenib in CL-1-5-F4 bearing animal model were investigated by tumor size evaluation, whole body computer tomography (CT) scan, Haemotoxylin and Eosin (H&E) stain and immunohistochemistry (IHC) stain. Our results demonstrated regorafenib significantly inhibited tumor growth and induced apoptosis through extrinsic/intrinsic pathways in NSCLC in vitro and in vivo. Furthermore, we also found the suppression of AKT/NF-κB signaling was required for regorafenib inhibited expression of progression-related and invasion-related proteins. Our finding indicated apoptosis induction and suppression of AKT/NF-κB signaling were associated with regorafenib-inhibited progression of NSCLC in vitro and in vivo.