Notch Transduction in Non-Small Cell Lung Cancer

A disulfiram derivative against lung cancer via the Notch signaling pathway without neurotoxicity and hepatotoxicity

The exploration of novel anti-lung cancer small-molecule drugs is important for drug resistance and adverse effects of chemotherapeutic drugs in current clinics. Disulfiram (DSF), as an antidote, has been proven to have excellent antitumor effects in combination with copper (Cu). However, the risk for potential neurotoxicity and hepatotoxicity in clinical use, as well as its poor water solubility, limits its use. In this study, we identified a DSF derivative, S-(N,N-diethyldithiocarbamoyl)-N-acetyl-L-cysteine, which could greatly increase the water solubility by converting it to a calcium salt (DS-NAC). The anti-lung cancer pharmacodynamic studies in vitro of DS-NAC were evaluated and a mouse model of lung cancer in situ was established to explore the therapeutic effects of DS-NAC compared with DSF and oxaliplatin (OXA). The results demonstrated that DS-NAC combined with Cu had superior cytotoxicity to DSF and OXA in the CCK8 assay against lung cancer cells, and exhibited potent anti-metastatic, epithelial-mesenchymal transition inhibition. In addition, DS-NAC showed better antitumor effects than DSF and comparable effects to OXA in lung cancer in situ model. In terms of the antitumor mechanism, we discovered that DS-NAC in combination with Cu exerted a greater inhibitory effect on the Notch pathway than DSF, which may account for its excellent antitumor effects. Finally, we verified the safety of DS-NAC in vivo, showing lower hepatotoxicity and neurotoxicity compared with DSF and OXA. DS-NAC is a promising anti-lung cancer drug with a favorable safety profile.

Comprehensive molecular and clinical insights into non-small cell lung cancer transformation to small cell lung cancer with an illustrative case report

Histologic transformation to small cell lung cancer (tSCLC) is a rare but increasingly recognised mechanism of acquired resistance to tyrosine kinase inhibitors (TKI) in patients with epidermal growth factor receptor (EGFR)-positive non-small cell lung cancer (NSCLC). Beyond its acknowledged role in TKI resistance, histologic transformation to SCLC might be an important, yet under-recognised, mechanism of resistance in NSCLC treated with immunotherapy. Our review identified 32 studies that investigated tSCLC development in patients with EGFR-mutated NSCLC treated with TKI therapy and 16 case reports of patients treated with immunotherapy. It revealed the rarity of tSCLC, with a predominance of EGFR exon 19 mutations and limited therapeutic options and outcomes. Across all analysed studies in EGFR-mutated NSCLC treated with TKI therapy, the median time to tSCLC development was ∼17 months, with a median overall survival of 10 months. Histologic transformation of EGFR-mutated NSCLC to SCLC is a rare, but challenging clinical problem with a poor prognosis. A small number of documented cases of tSCLC after immunotherapy highlight the need for rebiopsies at progression to diagnose this potential resistance mechanism. Further research is needed to better understand the mechanisms underlying this phenomenon and to develop more effective treatment strategies for patients with tSCLC.

Notch signaling pathway in cancer: from mechanistic insights to targeted therapies

Notch signaling, renowned for its role in regulating cell fate, organ development, and tissue homeostasis across metazoans, is highly conserved throughout evolution. The Notch receptor and its ligands are transmembrane proteins containing epidermal growth factor-like repeat sequences, typically necessitating receptor-ligand interaction to initiate classical Notch signaling transduction. Accumulating evidence indicates that the Notch signaling pathway serves as both an oncogenic factor and a tumor suppressor in various cancer types. Dysregulation of this pathway promotes epithelial-mesenchymal transition and angiogenesis in malignancies, closely linked to cancer proliferation, invasion, and metastasis. Furthermore, the Notch signaling pathway contributes to maintaining stem-like properties in cancer cells, thereby enhancing cancer invasiveness. The regulatory role of the Notch signaling pathway in cancer metabolic reprogramming and the tumor microenvironment suggests its pivotal involvement in balancing oncogenic and tumor suppressive effects. Moreover, the Notch signaling pathway is implicated in conferring chemoresistance to tumor cells. Therefore, a comprehensive understanding of these biological processes is crucial for developing innovative therapeutic strategies targeting Notch signaling. This review focuses on the research progress of the Notch signaling pathway in cancers, providing in-depth insights into the potential mechanisms of Notch signaling regulation in the occurrence and progression of cancer. Additionally, the review summarizes pharmaceutical clinical trials targeting Notch signaling for cancer therapy, aiming to offer new insights into therapeutic strategies for human malignancies.

Examining the contribution of Notch signaling to lung disease development

Notch pathway is a widely observed signaling system that holds pivotal functions in regulating various developmental cellular functions and operations. The Notch signaling mechanism is crucial for lung homeostasis, damage, and restoration. Based on increasing evidence, the Notch pathway has been identified, as critical for fibrosis and subsequently, the development of chronic fibroproliferative conditions in various organs and tissues. Recent research indicates that deregulation of Notch signaling correlates with the pathogenesis of significant pulmonary conditions, particularly chronic obstructive pulmonary disease (COPD), pulmonary fibrosis, asthma, pulmonary arterial hypertension (PAH), lung carcinoma, and pulmonary abnormalities in some hereditary disorders. In various cellular and tissue environments, and across both physiological and pathological conditions, multiple consequences of Notch activation have been observed. Studies have ascertained that the Notch signaling cascade exhibits close associations with various other signaling systems. This study provides an updated overview of Notch signaling's role, especially its link to fibrosis and its potential therapeutic implications. This study sheds light on the latest findings regarding the mechanisms and outcomes of irregular or lacking Notch activity in the onset and development of pulmonary diseases. As our insight into this signaling mechanism suggests that modulating Notch signaling might hold potential as a valuable additional therapeutic approach in upcoming research.

Notch signaling and targeted therapy in non-small cell lung cancer

The Notch signaling pathway plays pivotal roles in cell proliferation, stemness and invasion of non-small cell lung cancer (NSCLC). The human Notch family consists of four receptors, namely Notch1, Notch2, Notch3, and Notch4. These receptors are transmembrane proteins that play crucial roles in various cellular processes. Notch1 mostly acts as a pro-carcinogenic factor in NSCLC but sometimes acts as a suppressor. Notch2 has been demonstrated to inhibit the growth and progression of NSCLC, whereas Notch3 facilitates these biological behaviors of NSCLC. The role of Notch4 in NSCLC has not been fully elucidated, but it is evident that Notch4 promotes tumor progression. At present, drugs targeting the Notch pathway are being explored for NSCLC therapy, a majority of which are already in the stage of preclinical research and clinical trials, with bright prospects in the clinical treatment of NSCLC.

XL1R-Net: Explainable AI-driven improved L1-regularized deep neural architecture for NSCLC biomarker identification

BACKGROUND AND OBJECTIVE

Non-small cell lung cancer (NSCLC) exhibits intrinsic molecular heterogeneity, primarily driven by the mutation of specific biomarkers. Identification of these biomarkers would assist not only in distinguishing NSCLC into its major subtypes - Adenocarcinoma and Squamous Cell Carcinoma, but also in developing targeted therapy. Medical practitioners use one or more types of omic data to identify these biomarkers, copy number variation (CNV) being one such type. CNV provides a measure of genomic instability, which is considered a hallmark of carcinoma. However, the CNV data has not received much attention for biomarker identification. This paper aims to identify biomarkers for NSCLC using CNV data.

METHODS

An eXplainable AI (XAI)-driven L1-regularized deep learning architecture, XL1R-Net, is proposed that introduces a novel modification of the standard L1-regularized gradient descent algorithm to arrive at an improved deep neural classifier for NSCLC subtyping. Further, XAI-based feature identification has been used to leverage the trained classifier to uncover a set of twenty NCSLC-relevant biomarkers.

RESULTS

The identified biomarkers are evaluated based on their classification performance and clinical relevance. Using Multilayer Perceptron (MLP)-based model, a classification accuracy of 84.95% using 10-fold cross-validation is achieved. Moreover, the statistical significance test on the classification performance also revealed the superiority of the MLP model over the competitive machine learning models. Further, the publicly available Drug-Gene Interaction Database reveals twelve of the identified biomarkers as potentially druggable. The K-M Plotter tool was used to verify eighteen of the identified biomarkers with a high probability of predicting NSCLC patients' likelihood of survival. While nine of the identified biomarkers confirm the recent literature, five find mention in the OncoKB Gene List.

CONCLUSION

A set of seven novel biomarkers that have not been reported in the literature could be investigated for their potential contribution towards NSCLC therapy. Given NSCLC's genetic diversity, using only one omics data type may not adequately capture the tumor's complexity. Multiomics data and its integration with other sources will be examined in the future to better understand NSCLC heterogeneity.

Inhibitor of PD-1/PD-L1: a new approach may be beneficial for the treatment of idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a globally prevalent, progressive disease with limited treatment options and poor prognosis. Because of its irreversible disease progression, IPF affects the quality and length of life of patients and imposes a significant burden on their families and social healthcare services. The use of the antifibrotic drugs pirfenidone and nintedanib can slow the progression of the disease to some extent, but it does not have a reverse effect on the prognosis. The option of lung transplantion is also limited owing to contraindications to transplantation, possible complications after transplantation, and the risk of death. Therefore, the discovery of new, effective treatment methods is an urgent need. Over recent years, various studies have been undertaken to investigate the relationship between interstitial pneumonia and lung cancer, suggesting that some immune checkpoints in IPF are similar to those in tumors. Immune checkpoints are a class of immunosuppressive molecules that are essential for maintaining autoimmune tolerance and regulating the duration and magnitude of immune responses in peripheral tissues. They can prevent normal tissues from being damaged and destroyed by the immune response. While current studies have focused on PD-1/PD-L1 and CTLA-4, PD-1/PD-L1 may be the only effective immune checkpoint IPF treatment. This review discusses the application of PD-1/PD-L1 checkpoint in IPF, with the aim of finding a new direction for IPF treatment.

IER5L is a Prognostic Biomarker in Pan-Cancer Analysis and Correlates with Immune Infiltration and Immune Molecules in Non-Small Cell Lung Cancer

Purpose

Non-small cell lung cancer (NSCLC) accounts for the majority of lung cancer cases. Immediate early response 5 like (IER5L) plays crucial roles in progression and prognosis for several tumors, but its role in NSCLC remains unclear.

Patients and Methods

Gene expression and mutation profiles, DNA methylation data, and clinical information for cancers were downloaded from multiple databases. Relative expression, prognostic value, and correlation with disease progression of IER5L were analyzed in multiple cancers, including NSCLC. Upstream mechanisms were explored using a transcriptional network. Functional enrichment analysis, protein-protein interaction network, and gene set enrichment analysis were applied to study downstream mechanisms. Correlations of IER5L with immune infiltration, immune molecules, methylation status, and tumor mutation burden (TMB) were analyzed using R language. Finally, quantitative polymerase chain reaction (qPCR) and single-cell RNA sequencing (scRNA seq) analysis were performed to validate IER5L expression in NSCLC.

Results

Pan-cancer analysis displayed that IER5L expression was upregulated in multiple cancers and was associated with disease prognosis and progression, including NSCLC, which was validated using qPCR. scRNA seq analysis showed that multiple cells had increased IER5L expression. An EGR1-hsa-miR-8075-IER5L network was constructed for NSCLC. A total of 191 DEGs were identified between the two IER5L groups, which were significantly enriched in biological process of action potential, sodium ion transport, and regulation of membrane potential. Increased IER5L expression was primarily enriched in cell cycle, NOTCH signaling pathway, and oxidative phosphorylation pathway, and was correlated with increased regulatory T cells and neutrophils, elevated levels of immune molecules, and higher TMB.

Conclusion

Our findings show that increased IER5L expression was correlated with progression and prognosis in multiple cancers as well as with immune infiltration and immune molecules in NSCLC. Thus, IER5L is a prognostic biomarker in multiple cancers and may correlate with immunotherapeutic response in NSCLC.

Mechanism of TCF21 Downregulation Leading to Immunosuppression of Tumor-Associated Macrophages in Non-Small Cell Lung Cancer

Lung cancer, as one of the high-mortality cancers, seriously affects the normal life of people. Non-small cell lung cancer (NSCLC) accounts for a high proportion of the overall incidence of lung cancer, and identifying therapeutic targets of NSCLC is of vital significance. This study attempted to elucidate the regulatory mechanism of transcription factor 21 (TCF21) on the immunosuppressive effect of tumor-associated macrophages (TAM) in NSCLC. The experimental results revealed that the expression of TCF21 was decreased in lung cancer cells and TAM. Macrophage polarization affected T cell viability and tumor-killing greatly, and M2-type polarization reduced the viability and tumor-killing of CD8+T cells. Meanwhile, overexpression of TCF21 promoted the polarization of TAM to M1 macrophages and the enhancement of macrophages to the viability of T cells. Furthermore, there appears to be a targeting relationship between TCF21 and Notch, suggesting that TCF21 exerts its influence via the Notch signaling pathway. This study demonstrated the polarization regulation of TAM to regulate the immunosuppressive effect, which provides novel targets for the treatment of lung cancer.

Novel structured ADAM17 small-molecule inhibitor represses ADAM17/Notch pathway activation and the NSCLC cells' resistance to anti-tumour drugs

Background and aims: The outcomes of current treatment for non-small cell lung cancer (NSCLC) are unsatisfactory and development of new and more efficacious therapeutic strategies are required. The Notch pathway, which is necessary for cell survival to avert apoptosis, induces the resistance of cancer cells to antitumour drugs. Notch pathway activation is controlled by the cleavage of Notch proteins/receptors mediated by A disintegrin and metalloproteinase 17 (ADAM17); therefore, ADAM17 is a reliable intervention target for anti-tumour therapy to overcome the drug resistance of cancer cells. This work aims to develop and elucidate the activation of Compound 2b, a novel-structured small-molecule inhibitor of ADAM17, which was designed and developed and its therapeutic efficacy in NSCLC was assessed via multi-assays. Methods and results: A lead compound for a potential inhibitor of ADAM17 was explored via pharmacophore modelling, molecular docking, and biochemical screening. It was augmented by substituting two important chemical groups [R1 and R2 of the quinoxaline-2,3-diamine (its chemical skeleton)]; subsequently, serial homologs of the lead compound were used to obtain anoptimized compound (2b) with high inhibitory activity compared with leading compound against ADAM17 to inhibit the cleavage of Notch proteins and the accumulation of the Notch intracellular domain in the nuclei of NSCLC cells. The inhibitory activity of compound 2b was demonstrated by quantitative polymerase chain reaction and Western blotting. The specificity of compound 2b on ADAM17 was confirmed via point-mutation. Compound 2b enhanced the activation of antitumor drugs on NSCLC cells, in cell lines and nude mice models, by targeting the ADAM17/Notch pathway. Conclusion: Compound 2b may be a promising strategy for NSCLC treatment.

Therapeutic targeting approach on epithelial-mesenchymal plasticity to combat cancer metastasis

Epithelial-mesenchymal plasticity (EMP) is a process in which epithelial cells lose their characteristics and acquire mesenchymal properties, leading to increased motility and invasiveness, which are key factors in cancer metastasis. Targeting EMP has emerged as a promising therapeutic approach to combat cancer metastasis. Various strategies have been developed to target EMP, including inhibition of key signaling pathways, such as TGF-β, Wnt/β-catenin, and Notch, that regulate EMP, as well as targeting specific transcription factors, such as Snail, Slug, and Twist, that promote EMP. Additionally, targeting the tumor microenvironment, which plays a critical role in promoting EMP, has also shown promise. Several preclinical and clinical studies have demonstrated the efficacy of EMP-targeting therapies in inhibiting cancer metastasis. However, further research is needed to optimize these strategies and improve their clinical efficacy. Overall, therapeutic targeting of EMP represents a promising approach for the development of novel cancer therapies that can effectively inhibit metastasis, a major cause of cancer-related mortality.

Recent Developments and Challenges in Molecular-Targeted Therapy of Non-Small-Cell Lung Cancer

Treatment of lung cancer with conventional therapies, which include radiation, surgery, and chemotherapy results in multiple undesirable adverse or side effects. The major clinical challenge in developing new drug therapies for lung cancer is resistance, which involves mutations and disturbance in various signaling pathways. Molecular abnormalities related to epidermal growth factor receptor (EGFR), v-Raf murine sarcoma viral oncogene homolog B1 (B-RAF) Kirsten rat sarcoma virus (KRAS) mutations, translocation of the anaplastic lymphoma kinase (ALK) gene, mesenchymal-epithelial transition factor (MET) amplification have been studied to overcome the resistance and to develop new therapies for non-small cell lung cancer (NSCLC). But, inevitable development of resistance presents limits the clinical benefits of various new drugs. Here, we review current progress in the development of molecularly targeted therapies, concerning six clinical biomarkers: EGFR, ALK, MET, ROS-1, KRAS, and B-RAF for NSCLC treatment.

Pharmacokinetics, tissue distribution, and antitumor activity of a novel compound, NY-2, in non-small cell lung cancer

Introduction: ZLDI-8, which has a relatively strong antitumor activity, is an inhibitor of ADAM-17 and acts on the Notch signaling pathway. To further optimize its structure and improve its activity, a series of derivatives of ZLDI-8 was synthesized. NY-2 was the most effective derivative based on preliminary activity screening in vitro, with no obvious toxicity after administration in vivo. Method: The study aimed to determine the pharmacokinetics, tissue distribution, hepatotoxicity, nephrotoxicity, and antitumor activity of compound NY-2 on non-small cell lung cancer (NSCLC) in vitro and in vivo. Results: The in vivo pharmacokinetics parameters of NY-2 were better than those of ZLDI-8. The tissue distribution analysis showed that tail vein injection of 6 mg/kg of NY-2 in rats resulted in the highest concentration in the lung, so we hypothesized that NY-2 might be effective in the treatment of non-small cell lung cancer. In vitro assays showed that NY-2 significantly inhibited tumor colony formation, invasion, and migration and increased LDH activity and apoptosis in a concentration-dependent manner in non-small cell lung cancer cells. NY-2 also inhibited the formation of lung metastases without significant toxicity to major organs in nude mice. Conclusion: Compared with the parent compound, ZLDI-8, the activity and safety of NY-2 were higher. NY-2 acts on ADAM17 and simultaneously affects the downstream Notch1 and integrinβ1 signaling pathways resulting in antitumor activity. Thus, NY-2 could be a potential antitumor agent, inhibiting the organization and development of non-small cell lung cancer.

Low-Dose Metformin Treatment Reduces In Vitro Growth of the LL/2 Non-small Cell Lung Cancer Cell Line

Lung cancer maintains a relatively small survival rate (~19%) over a 5-year period and up to 80-85% of all lung cancer diagnoses are Non-Small Cell Lung Cancer (NSCLC). To determine whether metformin reduces non-small cell lung cancer (NSCLC) LL/2 cell growth, cells were grown in vitro and treated with metformin for 48 h. qPCR was used to assess genes related to cell cycle regulation and pro-apoptotic markers, namely Cyclin D, CDK4, p27, p21, and HES1. Treatment with 10 mM metformin significantly reduced HES1 expression (p = 0.011). Furthermore, 10 mM metformin treatment significantly decreased REDD1 (p = 0.0082) and increased p-mTOR Ser2448 (p = 0.003) protein expression. Control cells showed significant reductions in phosphorylated p53 protein expression (p = 0.0367), whereas metformin treated cells exhibited reduced total p53 protein expression (p = 0.0078). There were no significant reductions in AMPK, PKB/AKT, or STAT3. In addition, NSCLC cells were treated for 48 h. with 10 mM metformin, 4 µM gamma-secretase inhibitor (GSI), or the combination of metformin (10 mM) and GSI (4 µM) to determine the contribution of respective signaling pathways. Metformin treatment significantly reduced total nucleus expression of the proliferation maker Ki-67 with an above 65% reduction in Ki-67 expression between control and metformin-treated cells (p = 0.0021). GSI (4 µM) treatment significantly reduced Ki-67 expression by ~20% over 48 h (p = 0.0028). Combination treatment (10 mM metformin and 4 µM GSI) significantly reduced Ki-67 expression by more than 50% over 48 h (p = 0.0245). As such, direct administration of metformin (10 mM for 48 h) proved to be an effective pharmaceutical agent in reducing the proliferation of cultured non-small cell cancer cells. These intriguing in vitro results, therefore, support the further study of metformin in appropriate in vivo models as an anti-oncogenic agent and/or an adjunctive therapy.

miR-140-3p enhances the sensitivity of LUAD cells to antitumor agents by targeting the ADAM10/Notch pathway

Background: The Notch pathway, which is related to the drug-resistance of lung adenocarcinoma (LUAD) type of non-small cell lung cancer (NSCLC) cells, is activated by cleavage of Notch proteins mediated by ADAMs, ADAM10 or ADAM17. Methods: In the present study, our results demonstrated that of these two ADAMs, the expression of ADAM10 in clinical samples of the LUAD type of NSCLC was much higher than that of ADAM17, while miR-140-3p - an miRNA that could target ADAM10 - was identified by an online tool: miRDB (miRNA database). The detail function and mechanism of miR-140-3p in regulating the sensitivity of NSCLC cells to antitumor drugs was systematically explored in vitro and in vivo. Results: In A549, a typical NSCLC LUAD cell line, miR-140-3p decreased ADAM10 expression and repressed activation of the Notch pathway by repressing cleavage of Notch proteins. The expression of miR-140-3p was negatively related to ADAM10 in clinical specimens. Nucleocytoplasmic separation/subfraction assays showed that miR-140-3p was able to inhibit the cleavage of Notch protein, and led to the accumulation of Notch intracellular domains (NICD) in the nucleus. Overexpression of miR-140-3p enhanced the sensitivity of A549 cells to antitumor agents by targeting the 3'UTR region of ADAM10 mRNA in both cultured cells and in vivo models. Conclusion: ADAM10 plays a major role in LUAD, and miR-140-3p acts on ADAM10 and inhibits its expression and the cleavage of Notch protein, leading to the inhibition the activity of the Notch pathway, and ultimately upregulating LUAD cell sensitivity to anti- tumor drugs.

Roles of transducin-like enhancer of split (TLE) family proteins in tumorigenesis and immune regulation

Mammalian transducin-like enhancer of split family proteins (TLEs) are homologous to Drosophila Groucho (Gro) and are essential transcriptional repressors. Seven TLE family members, TLE1-7, have been identified to date. These proteins do not bind DNA directly; instead, they bind a set of transcription factors and thereby inhibit target gene expression. Loss of TLEs in mice usually leads to defective early development; however, TLE functions in developmentally mature cells are unclear. Recent studies have revealed that TLEs are dysregulated in certain human cancer types and may function as oncogenes or tumor suppressors in different contexts. TLE levels also affect the efficacy of cancer treatments and the development of drug resistance. In addition, TLEs play critical roles in the development and function of immune cells, including macrophages and lymphocytes. In this review, we provide updates on the expression, function, and mechanism of TLEs; discuss the roles played by TLEs in tumorigenesis and the inflammatory response; and elaborate on several TLE-associated signaling pathways, including the Notch, Wnt, and MAPK pathways. Finally, we discuss potential strategies for targeting TLEs in cancer therapy.

Bruceine H Mediates EGFR-TKI Drug Persistence in NSCLC by Notch3-Dependent β-Catenin Activating FOXO3a Signaling

Tyrosine kinase inhibitors (TKIs) targeting epidermal growth factor receptor (EGFR) protein serve as a critical pillar in the treatment of non-small cell lung cancer (NSCLC), but resistance is universal. Identifying the potential key factors of drug resistance to EGFR-TKIs is essential to treat patients with EGFR mutant lung cancer. Our research here shows that bruceine H suppressed the proliferation, migration, and invasion of lung cancer cells; inhibited the growth of human NSCLC cell xenografts; and enhanced the therapeutic effects of gefitinib in the PC-9/GR xenograft models, possibly by inhibiting Notch3. In order to analyze the potential targets of the combination of Notch3 and EGFR-TKIs on resistance to EGFR, we analyzed the differences of gene expression between NSCLC tissues and EGFR-driven gefitinib-resistant tumoral groups and then identify through the WGCNA key genes that may provide therapeutic targets for TKI-resistant lung cancer xenograft models. We confirmed that EGFR-TKI in combination with Notch3 inhibitor can inhibit the expression of β-catenin and enhance the level of FOXO3a, leading to improved recurrence-free survival and overall survival of the xenotransplantation model. These results support that the combination of gefitinib and bruceine H may provide a promising alternative strategy for treating acquired EGFR-TKI resistance in patients with NSCLC.

Small cell lung cancer transformation: From pathogenesis to treatment

Small cell lung cancer (SCLC) is a type of neuroendocrine tumor with high malignancy and poor prognosis. Besides the de novo SCLC, there is transformed SCLC, which has similar characteristics of pathological morphology, molecular characteristics, clinical manifestations and drug sensitivity. However, de novo SCLC and transformed SCLC have different pathogenesis and tumor microenvironment. SCLC transformation is one of the mechanisms of resistance to chemotherapy, immunotherapy, and targeted therapy in NSCLC. Two hypotheses have been used to explain the pathogenesis of SCLC transformation. Although SCLC transformation is not common in clinical practice, it has been repeatedly identified in many small patient series and case reports. It usually occurs in epidermal growth factor receptor (EGFR) mutant lung adenocarcinoma after treatment with tyrosine kinase inhibitors (TKIs). SCLC transformation can also occur in anaplastic lymphoma kinase (ALK)-positive lung cancer after treatment with ALK inhibitors and in wild-type EGFR or ALK NSCLC treated with immunotherapy. Chemotherapy was previously used to treat transformed SCLC, yet it is associated with an unsatisfactory prognosis. We comprehensively review the advancements in transformed SCLC, including clinical and pathological characteristics, and the potential effective treatment after SCLC transformation, aiming to give a better understanding of transformed SCLC and provide support for clinical uses.

Exhaled phospholipid transfer protein and hepatocyte growth factor receptor in lung adenocarcinoma

BACKGROUND

Screening decreases mortality among lung cancer patients but is not widely implemented, thus there is an unmet need for an easily accessible non-invasive method to enable early diagnosis. Particles in exhaled air offer a promising such diagnostic tool. We investigated the validity of a particles in exhaled air device (PExA) to measure the particle flow rate (PFR) and collect exhaled breath particles (EBP) to diagnose primary lung adenocarcinoma (LUAD).

METHODS

Seventeen patients listed for resection of LUAD stages IA-IIIA and 18 non-cancer surgical control patients were enrolled. EBP were collected before and after surgery for LUAD, and once for controls. Proteomic analysis was carried out using a proximity extension assay technology. Results were validated in both plasma from the same cohort and with microarray data from healthy lung tissue and LUAD tissue in the GSE10072 dataset.

RESULTS

Of the 92 proteins analyzed, levels of five proteins in EBP were significantly higher in the LUAD patients compared to controls. Levels of phospholipid transfer protein (PLTP) and hepatocyte growth factor receptor (MET) decreased in LUAD patients after surgery compared to control patients. PFR was significantly higher in the LUAD cohort at all timepoints compared to the control group. MET in plasma correlated significantly with MET in EBP.

CONCLUSION

Collection of EBP and measuring of PFR has never been performed in patients with LUAD. In the present study PFR alone could distinguish between LUAD and patients without LUAD. PLTP and MET were identified as potential biomarkers to evaluate successful tumor excision.

Cigarette smoke upregulates Notch-1 signaling pathway and promotes lung adenocarcinoma progression

Notch-1 pathway plays an important role in lung carcinoma, stem cell regulation, cellular communication, growth and differentiation. Cigarette smoke is involved in the regulation of Notch signaling. However, current data regarding the impact of cigarette smoke on the Notch pathway in lung cancer progression are limited. The present study aimed to explore whether cigarette smoke exposure altered Notch-1 pathway in ex-vivo (surgical samples of lung parenchyma from non-smoker and smoker patients with lung adenocarcinoma) and in vitro (adenocarcinoma A549 cell line) approaches. The expression of Notch-1, Jagged-1 and CD133 in surgical samples was evaluated by immunohistochemistry. A549 were exposed to cigarette smoke extracts (2.5% and 5% CSE for 6, 24 and 48 h) and the expression of Notch-1, Jagged-1 and Hes-1 was evaluated by Real-Time PCR and Western Blot (nuclear fractions). Expression and localization of Notch-1, Hes-1, CD133 and ABCG2 were assessed by immunofluorescence. The expression of survivin and Ki-67 was assessed by flow cytometry following CSE exposure and inhibition of Notch-1 signaling. Smokers lung parenchyma exhibited higher expression of Notch-1. CSE exposure increased Notch-1 and Hes-1 gene and nuclear protein expression in A549. Immunofluorescence confirmed higher expression of nuclear Hes-1 in CSE-stimulated A549 cells. CSE increased both survivin and Ki-67 expression and this effect was reverted by inhibition of the Notch-1 pathway. In conclusion, these data show that cigarette smoke may promote adenocarcinoma progression by activating the Notch-1 pathway thus supporting its role as hallmark of lung cancer progression and as a new target for lung cancer treatment.

Cross talk between autophagy and oncogenic signaling pathways and implications for cancer therapy

Autophagy is a highly conserved metabolic process involved in the degradation of intracellular components including proteins and organelles. Consequently, it plays a critical role in recycling metabolic energy for the maintenance of cellular homeostasis in response to various stressors. In cancer, autophagy either suppresses or promotes cancer progression depending on the stage and cancer type. Epithelial-mesenchymal transition (EMT) and cancer metastasis are directly mediated by oncogenic signal proteins including SNAI1, SLUG, ZEB1/2, and NOTCH1, which are functionally correlated with autophagy. In this report, we discuss the crosstalk between oncogenic signaling pathways and autophagy followed by possible strategies for cancer treatment via regulation of autophagy. Although autophagy affects EMT and cancer metastasis, the overall signaling pathways connecting cancer progression and autophagy are still illusive. In general, autophagy plays a critical role in cancer cell survival by providing a minimum level of energy via self-digestion. Thus, cancer cells face nutrient limitations and challenges under stress during EMT and metastasis. Conversely, autophagy acts as a potential cancer suppressor by degrading oncogenic proteins, which are essential for cancer progression, and by removing damaged components such as mitochondria to enhance genomic stability. Therefore, autophagy activators or inhibitors represent possible cancer therapeutics. We further discuss the regulation of autophagy-dependent degradation of oncogenic proteins and its functional correlation with oncogenic signaling pathways, with potential applications in cancer therapy.

SLC6A8 is involved in the progression of non-small cell lung cancer through the Notch signaling pathway

Background

Solute carrier family 6 member 8 (SLC6A8) is known to be involved in the development of human tumors; however, the effect of SLC6A8 on the growth of non-small cell lung cancer (NSCLC) remains unclear. Here, we explored the role and potential action mechanism of SLC6A8 in NSCLC.

Methods

We used public databases [Oncomine, Gene Expression Omnibus (GEO), and The Cancer Genome Atlas (TCGA)] to explore the expression of SLC6A8 in NSCLC. Additionally, we used immunohistochemistry to detect the expression of SLC6A8 in NSCLC clinicopathological tissues (cancer and adjacent tissues) and Western blotting to detect the expression of SLC6A8 in NSCLC clinicopathological tissues, NSCLC cell lines (A549, H1299, H520, and H1975), and a normal epithelial cell line (BEAS-2B). Using overexpression and knockdown of the SLC6A8 gene, we analyzed the in vitro effects of SLC6A8 on the proliferation, invasion, and epithelial-mesenchymal transition (EMT) of NSCLC and also the possible molecular mechanism with Notch signaling pathway.

Results

Bioinformatic analysis demonstrated that SLC6A8 is highly expressed in NSCLC and is related to poor prognosis. We found that the expression of the SLC6A8 protein in human lung cancer tissues was significantly higher than that in adjacent tissues. In addition, it was also significantly higher in lung cancer cell lines (A549, H1299, H520, and H1975) than that in normal lung epithelium-BEAS-2B. Moreover, SLC6A8 overexpression promotes the proliferation, migration and invasion in vitro in NSCLC, accompanied by the activation of notch signaling pathway and the up-regulation of MMP9 and E-cadherin proteins. Knocking down SLC6A8 can inhibit the above effects on cells.

Conclusions

SLC6A8 promotes the malignant progression of NSCLC and activates the Notch signaling pathway. Therefore, SLC6A8 is expected to become a molecular target for NSCLC treatment.

miR‑34c‑5p targets Notch1 and suppresses the metastasis and invasion of cervical cancer

Micro (mi)RNAs are crucial participants in the progression of cervical cancer (CC). Growing evidence indicates that miRNA (miR)-34c-5p is a pivotal tumor suppressor in numerous types of cancer and its functions in CC require further investigating. The present study demonstrated that there was a decreased level of miR-34c-5p in CC-associated cell lines compared with healthy control samples. It also demonstrated that miR-34c-5p targeted Notch1 and suppressed CC progression. Dual-Luciferase reporter assays verified the targeted relationship of miR-34c-5p and Notch1. The expression of Notch1 in HeLa cells was markedly reduced following miR-34c-5p overexpression and the proliferation, migration and invasion of HeLa cells were reduced although apoptosis was accelerated. However, overexpression of miR-34c-5p was reversed following the addition of Notch1, which supported the finding of the targeted relationship between miR-34c-5p and Notch1. Flow cytometry demonstrated that miR-34c-5p inhibited the proliferation of HeLa cells while accelerating apoptosis. The present study concluded that miR-34c-5p was a tumor suppressor in CC and may be a novel measure for the future treatment of CC.