Nuclear factor-kappaB (NF-kappaB) is frequently expressed in lung cancer and preneoplastic lesions

Dissecting the pleiotropic roles of reactive oxygen species (ROS) in lung cancer: From carcinogenesis toward therapy

Lung cancer is a major cause of morbidity and mortality. The specific pulmonary structure to directly connect with ambient air makes it more susceptible to damage from airborne toxins. External oxidative stimuli and endogenous reactive oxygen species (ROS) play a crucial role in promoting lung carcinogenesis and development. The biological properties of higher ROS levels in tumor cells than in normal cells make them more sensitive and vulnerable to ROS injury. Therefore, the strategy of targeting ROS has been proposed for cancer therapy for decades. However, it is embarrassing that countless attempts at ROS-based therapies have had very limited success, and no FDA approval in the anticancer list was mechanistically based on ROS manipulation. Even compared with the untargetable proteins, such as transcription factors, ROS are more difficult to be targeted due to their chemical properties. Thus, the pleiotropic roles of ROS provide therapeutic potential for anticancer drug discovery, while a better dissection of the mechanistic action and signaling pathways is a prerequisite for future breakthroughs. This review discusses the critical roles of ROS in cancer carcinogenesis, ROS-inspired signaling pathways, and ROS-based treatment, exemplified by lung cancer. In particular, an eight considerations rule is proposed for ROS-targeting strategies and drug design and development.

Inhibition of NF-kB and COX-2 by andrographolide regulates the progression of cervical cancer by promoting PTEN expression and suppressing PI3K/AKT signalling pathway

In the face of recent advances in Cervical cancer (CC) treatment, therapeutic and surgical procedures for CC management are still inadequate. In the current study for the first time Andrographolide (Andro) has been explored for its multitarget therapeutic efficacy on NF-kB, COX-2, and PI3K/AKT expressions together in CC. The expression levels of NF-kB, COX-2, PI3K and PTEN in the CC patient samples, both at mRNA and protein levels have shown significant association with poor survival and increased tumor aggressiveness. The binding efficacy of Andro was investigated using molecular docking and molecular dynamic simulations, and the protein and ligand complex for NF-kB and COX-2 has shown high binding energy. Andro displayed cytotoxicity by impeding the in-vitro proliferation of CC cells. Andro significantly supressed the NF-kB, COX-2, and PI3K expression and enhanced the expression levels of PTEN at protein levels in-vitro. Andro induced apoptosis in a dose dependent manner and significantly inhibited the migration and invasion of CC cells. Andro exhibited similar activity in-vivo and suppressed the CC tumor growth in xenograft C57BL/6 mice model. The anti-tumor activity of Andro, both in-vitro and in-vivo has shown considerable downregulation of NF-kB and COX-2 and induced apoptosis through impeding the PI3K/AKT signalling pathway. These findings from the above study projects, administration of Andro as an effective alternate safe compound to curtail and impede cervical cancer progression.

The role of α7-nAChR-mediated PI3K/AKT pathway in lung cancer induced by nicotine

Nicotine enters the environment mainly through human activity, as well as natural sources. This review article examines the increasing evidence implicating nicotine in the initiation and progression of lung cancer. Moreover, it primarily focuses on elucidating the activation mechanism of phosphoinositide 3-kinase (PI3K)/protein kinase B (PKB, also known as AKT) signaling pathway, regulated by α7 subtype nicotinic acetylcholine receptor (α7-nAChR), in relation to the proliferation, invasion, and metastasis of lung cancer cells induced by nicotine, as well as nicotine-mediated anti-apoptotic effects. This process involves PI3K/AKT phosphorylated-B-cell lymphoma-2 (Bcl-2) family proteins, PI3K/AKT/mammalian target of rapamycin (mTOR), PI3K/AKT/nuclear factor-κB (NF-κB), hepatocyte growth factor (HGF)/cellular-mesenchymal epithelial transition factor (c-Met)-induced PI3K/AKT and PI3K/AKT activated-hypoxia-inducible factor-1α (HIF-1α)/vascular endothelial growth factor (VEGF) pathways. In addition, we also deliberated on the related challenges and upcoming prospects within this field. These lay the foundation for further study on nicotine, lung tumorigenesis, and PI3K/AKT related molecular mechanisms. This work has the potential to significantly contribute to the treatment and prognosis of gastric cancer in smokers. Besides, the crucial significance of PI3K/AKT signaling pathway in multiple molecular pathways also suggests that its target antagonists may inhibit the development and progression of lung cancer, providing a possible new perspective for solving the problem of nicotine-promoted lung cancer. The emerging knowledge about the carcinogenic mechanisms of nicotine action should be considered during the environmental assessment of tobacco and other nicotine-containing products.

Effects of Ottonia anisum plant extract on local anesthetic, analgesic, anti-inflammatory and HCl‑induced acute lung injury activities: a study in animal models

Ottonia anisum (O. anisum), belonging to the family Piperaceae, is renowned for its medicinal properties. The plant is rich in alkaloids, terpenoids and flavonoids with recorded bioactivities. The stems, roots, and leaves, of the O. anisum have been extensively used in the folk medicine. Therefore, the present study was conducted to examine the pharmacological activities of O. anisum root extract. Methanolic root extract of O. anisum was assessed for local anesthetic, analgesic, anti-inflammatory and HCl-induced acute lung injury activities in animal models. Local anesthetic activity assessed in frog and guinea pigs through foot withdrawal reflex and intradermal wheal method, respectively, revealed the dose-dependent onset time of anesthesia response. In the case of HCl-induced ALI, the mice group orally administered with O. anisum extract were assessed for bronchoalveolar lavage fluid (BLF) contents, oxidative stress, and proinflammatory molecules. The analysis revealed the reduction in inflammatory molecules, neutrophils, and oxidative stress in the extract treated mice group. In addition, the redox homeostasis, reduced GSH and the catalase activity was found to be restored in the treated groups. Intriguingly, the genes associated with the NFkB expression was found to be downregulated in O. anisum extract treated groups. Moreover, the extract unveiled the significant analgesic and anti-inflammatory activities. Overall, the findings emphasize the clinical applicability of O. anisum extract in the treatment of ALI as well as the potential usage in local anesthetic, analgesic, and anti-inflammatory agents during the treatments.

Nuclear factor kappa B expression in non-small cell lung cancer

In this mini-review, we discuss the role of NF-κB, a proinflammatory transcription factor, in the expression of genes involved in inflammation, proliferation, and apoptosis pathways, and link it with prognosis of various human cancers, particularly non-small cell lung cancer (NSCLC). We and others have shown that NF-κB activity can be impacted by post-translational S-glutathionylation through reversible formation of a mixed disulfide bond between its cysteine residues and glutathione (GSH). Clinical data analysis showed that high expression of NF-κB correlated with shorter overall survival (OS) in NSCLC patients, suggesting a tumor promotion function for NF-κB. Moreover, NF-κB expression was associated with tumor stage, lymph node metastasis, and 5-year OS in these patients. NF-κB was over-expressed in the cytoplasm of tumor tissue compared to adjacent normal tissues. S-glutathionylation of NF-κB caused negative regulation by interfering with DNA binding activities of NF-κB subunits. In response to oxidants, S-glutathionylation of NF-κB also correlated with enhanced lung inflammation. Thus, S-glutathionylation is an important contributor to NF-κB regulation and clinical results highlight the importance of NF-κB in NSCLC, where NF-κB levels are associated with unfavorable prognosis.

The anticarcinogenic effect of eugenol on lung cancer induced by diethylnitrosamine/2-acetylaminofluorene in Wistar rats: insight on the mechanisms of action

This study was designed to assess the ameliorative effects of eugenol and to propose the possible mechanisms of action of eugenol in diethylnitrosamine (DENA)/acetylaminofluorene (AAF)-caused lung cancer in Wistar rats. To induce lung cancer, DENA at a dose of 150 mg/kg body weight (b.wt) for 2 weeks were intraperitoneally injected once each week and AAF was administered orally at a dose of 20 mg/kg b.wt. four times each week for the next 3 weeks. DENA/AAF-administered rats were orally supplemented with eugenol at a dose of 20 mg/kg b.wt administered once a day until 17 weeks starting from the 1st week of DENA administration. Lung histological lesions, including sheets of tumor cells, micropapillary adenocarcinoma, and apoptotic cells, resulting from the DENA/AAF dosage, were ameliorated by eugenol treatment. However, a significant drop in the levels of LPO in the lungs and a remarkable rise in GSH content and GPx and SOD activities were observed in DENA/AAF-administered rats treated with eugenol compared with those in DENA/AAF-administered controls. Moreover, in DENA/AAF-administered rats, eugenol supplementation significantly reduced TNF-α and IL-1β levels and mRNA expression levels of NF-κB, NF-κB p65, and MCP-1 but significantly elevated the level of Nrf2. Furthermore, the DENA/AAF-administered rats treated with eugenol exhibited a significant downregulation of Bcl-2 expression levels in addition to a significant upregulation in P53 and Bax expression levels. Otherwise, the administration of DENA/AAF elevated the protein expression level of Ki-67, and this elevation was reversed by eugenol treatment. In conclusion, eugenol has effective antioxidant, anti-inflammatory, proapoptotic, and antiproliferative properties against lung cancer.

Karyopherin Subunit Alpha 1 Enhances the Malignant Behaviors of Colon Cancer Cells via Promoting Nuclear Factor-κB p65 Nuclear Translocation

BACKGROUND/AIMS

Aberrant nuclear factor-κB p65 (NF-κB p65) nuclear import commonly occurs in multiple cancers, including colon cancer. According to BioGRID, we noted that Karyopherin subunit alpha 1 (KPNA1), an important molecular transporter between the nucleus and the cytoplasm, may interact with NF-κB p65. KPNA1 itself is highly expressed in colon adenocarcinoma samples (N = 286) based on The Cancer Genome Atlas (TCGA) database. We aimed to explore the role of KPNA1 in colonic carcinogenesis and to determine whether NF-κB p65 nuclear translocation was involved.

METHODS

KPNA1 expressions at mRNA and protein levels were analyzed in colon cancer tissues. The regulatory effect of KPNA1 on malignant biological properties was detected in SW480 and HCT116 colon cancer cells. Coimmunoprecipitation and immunofluorescence were performed to verify the relationship between KPNA1 and NF-κB p65. KPNA1 ubiquitination was also preliminarily investigated.

RESULTS

KPNA1 was firstly confirmed as a significantly upregulated gene in our collected clinical colon cancer samples (N = 35). KPNA1 depletion inhibited cell proliferation, induced cell cycle arrest, and diminished migratory and invasive capacity of SW480 and HCT116 cells. Colon cancer cells overexpressing KPNA1 acquired more aggressive behaviors. KPNA1 acted as a transporter to induce the nuclear accumulation of NF-κB p65, thereby activating NF-κB signaling pathway in colon cancer cells. Furthermore, HECT, C2, and WW Domain-Containing E3 Ubiquitin (HECW2) interacted with KPNA1 to induce its ubiquitination. KPNA1 labeled with polyubiquitins was degraded through ubiquitin-proteasome system.

CONCLUSION

The present study uncovers a role of KPNA1-NF-κB p65 axis in promoting colonic carcinogenesis.

Investigating regulated signaling pathways in therapeutic targeting of non-small cell lung carcinoma

Non-small cell lung carcinoma (NSCLC) is the most common malignancy worldwide. The signaling cascades are stimulated via genetic modifications in upstream signaling molecules, which affect apoptotic, proliferative, and differentiation pathways. Dysregulation of these signaling cascades causes cancer-initiating cell proliferation, cancer development, and drug resistance. Numerous efforts in the treatment of NSCLC have been undertaken in the past few decades, enhancing our understanding of the mechanisms of cancer development and moving forward to develop effective therapeutic approaches. Modifications of transcription factors and connected pathways are utilized to develop new treatment options for NSCLC. Developing designed inhibitors targeting specific cellular signaling pathways in tumor progression has been recommended for the therapeutic management of NSCLC. This comprehensive review provided deeper mechanistic insights into the molecular mechanism of action of various signaling molecules and their targeting in the clinical management of NSCLC.

KRAS-Mutant Lung Cancer: Targeting Molecular and Immunologic Pathways, Therapeutic Advantages and Restrictions

RAS mutations are among the most common oncogenic mutations in human cancers. Among RAS mutations, KRAS has the highest frequency and is present in almost 30% of non-small-cell lung cancer (NSCLC) patients. Lung cancer is the number one cause of mortality among cancers as a consequence of outrageous aggressiveness and late diagnosis. High mortality rates have been the reason behind numerous investigations and clinical trials to discover proper therapeutic agents targeting KRAS. These approaches include the following: direct KRAS targeting; synthetic lethality partner inhibitors; targeting of KRAS membrane association and associated metabolic rewiring; autophagy inhibitors; downstream inhibitors; and immunotherapies and other immune-modalities such as modulating inflammatory signaling transcription factors (e.g., STAT3). The majority of these have unfortunately encountered limited therapeutic outcomes due to multiple restrictive mechanisms including the presence of co-mutations. In this review we plan to summarize the past and most recent therapies under investigation, along with their therapeutic success rate and potential restrictions. This will provide useful information to improve the design of novel agents for treatment of this deadly disease.

Mechanism of andrographis paniculata on lung cancer by network pharmacology and molecular docking

BACKGROUND

Traditional Chinese medicine (TCM) has been widely recognized and accepted worldwide to provide favorable therapeutic effects for cancer patients. As Andrographis paniculata has an anti-tumor effect, it might inhibit lung cancer.

OBJECTIVE

The drug targets and related pathways involved in the action of Andrographis paniculata against lung cancer were predicted using network pharmacology, and its mechanism was further explored at the molecular level.

METHODS

This work selected the effective components and targets of Andrographis paniculata against the Traditional Chinese Medicine System Pharmacology (TCMSP) database. Targets related to lung cancer were searched for in the GEO database (accession number GSE136043). The volcanic and thermal maps of differential expression genes were produced using the software R. Then, the target genes were analyzed by GO and KEGG analysis using the software R. This also utilized the AutoDock tool to study the molecular docking of the active component structures downloaded from the PubChem database and the key target structures downloaded from the PDB database, and the docking results were visualized using the software PyMol.

RESULTS

The results of molecular docking show that wogonin, Mono-O-methylwightin, Deoxycamptothecine, andrographidine F_qt, Quercetin tetramethyl (3',4',5,7) ether, 14-deoxyandrographolide, andrographolide-19-β-D-glucoside_qt and 14-deoxy-11-oxo-andrographolide were potential active components, while AKT1, MAPK14, RELA and NCOA1 were key targets.

CONCLUSION

This study showed the main candidate components, targets, and pathways involved in the action of Andrographis paniculata against lung cancer.

An L-theanine derivative targets against SARS-CoV-2 and its Delta and Omicron variants

Recent research efforts have shown that tea has activities against SARS-CoV-2. However, the active compounds and the action mechanisms are largely unknown. Here we study the inhibitory potential of L-theanine from tea and its semi-synthesized derivative, a small-molecule fluorescent compound, ethyl 6-bromocoumarin-3-carboxylyl L-theanine (TBrC) against infection and replication of SARS-CoV-2 and the underlying mechanisms of action. We reveal that TBrC has potential activities against SARS-CoV-2 in addition to its activity against lung cancer. TBrC showed extracellular inhibition of SARS-CoV-2 M^pro/3CL and the host cell receptor ACE2 while interacting with the viral spike glycoproteins (wild-type, Delta, and Omicron mutants). Moreover, TBrC and L-theanine significantly suppressed growth and TNFα-induced nuclear transcriptional activation of NF-κB in human lung cancer cells without affecting the viability of normal lung cells, suggesting a potential protection of TBrC and L-theanine from pulmonary damages in SARS-CoV-2 infected patients, especially for lung cancer patients with SARS-CoV-2 infection.

Identification of Potential Biomarkers and Small Molecule Drugs for Cutaneous Melanoma Using Integrated Bioinformatic Analysis

Background: Cutaneous melanoma (CM) is a type of skin cancer with a high fatality rate, and its pathogenesis has not yet been fully elucidated.

Methods: We obtained the gene expression datasets of CM through the Gene Expression Omnibus (GEO) database. Subsequently, robust rank aggregation (RRA) method was used to identify differentially expressed genes (DEGs) between CM cases and normal skin controls. Gene functional annotation was performed to explore the potential function of the DEGs. We built the protein–protein interaction (PPI) network by the Interactive Gene database retrieval tool (STRING) and selected hub modules by Molecular Complexity Detection (MCODE). We furthered and validated our results using the TCGA-GTEX dataset. Finally, potential small molecule drugs were predicted by CMap database and verified by molecular docking method.

Results: A total of 135 DEGs were obtained by RRA synthesis analysis. GMPR, EMP3, SLC45A2, PDZD2, NPY1R, DLG5 and ADH1B were screened as potential targets for CM. Furazolidone was screened as a potential small molecule drug for the treatment of CM, and its mechanism may be related to the inhibition of CM cell proliferation by acting on GMPR.

Conclusion: We identified seven prognostic therapeutic targets associated with CM and furazolidone could be used as a potential drug for CM treatment, providing new prognostic markers, potential therapeutic targets and small molecule drugs for the treatment and prevention of CM.

FGFC1 Exhibits Anti-Cancer Activity via Inhibiting NF-κB Signaling Pathway in EGFR-Mutant NSCLC Cells

FGFC1, an active compound isolated from the culture of marine fungi Stachybotrys longispora FG216, elicits fibrinolytic, anti-oxidative, and anti-inflammatory activity. We have previously reported that FGFC1 inhibited the proliferation, migration, and invasion of the non-small cell lung cancer (NSCLC) cells in vitro. However, the precise mechanisms of FGFC1 on NSCLC and its anti-cancer activity in vivo remains unclear. Hence, this study was focused to investigate the effects and regulatory mechanisms of FGFC1 on two NSCLC cell lines, EGFR-mutant PC9 (ex19del) and EGFR wild-type H1299. Results suggested that FGFC1 significantly inhibited proliferation, colony formation, as well as triggered G0/G1 arrest and apoptosis of PC9 cells in a dose- and time-dependent manner, but no obvious inhibitory effects were observed in H1299 cells. Subsequently, transcriptome analysis revealed that FGFC1 significantly down-regulated 28 genes related to the NF-κB pathway, including IL-6, TNF-α, and ICAM-1 in the PC9 cells. We further confirmed that FGFC1 decreased the expression of protein p-IKKα/β, p-p65, p-IκB, IL-6, and TNF-α. Moreover, NF-κB inhibitor PDTC could strengthen the effects of FGFC1 on the expression of CDK4, Cyclin D1, cleaved-PARP-1, and cleaved-caspase-3 proteins, suggesting that the NF-κB pathway plays a major role in FGFC1-induced cell cycle arrest and apoptosis. Correspondingly, the nuclear translocation of p-p65 was also suppressed by FGFC1 in PC9 cells. Finally, the intraperitoneal injection of FGFC1 remarkably inhibited PC9 xenograft growth and decreased the expression of Ki-67, p-p65, IL-6, and TNF-α in tumors. Our results indicated that FGFC1 exerted anti-cancer activity in PC9 cells via inhibiting the NF-κB signaling pathway, providing a possibility for FGFC1 to be used as a lead compound for the treatment of NSCLC in the future.

Inhibition of NF-кB Expression in LPS-Induced RAW264.7 Macrophage Cells by a Thiazolidinone Derivative (TZDOCH2CH3)

To date, various derivatives of thiazolidinone in a variety of cell lines have been investigated. The present study aimed to evaluate the toxicity and inhibitory effects of a thiazolidinone derivative called 5-(2,4-bis-4-ethoxy-phenyl azo)-3-hydroxy-benzylidine)-2,4-thiazolidinone (TZD-OCH2CH3) on the expression of NF-кB in LPS-induced RAW264.7 macrophage cell lines. Different concentrations of the MTT assay(0-120 μg/mL) were performed to estimate the biological rate of the cells. The half-maximal inhibitory concentration (IC50) of TZD-OCH2CH3-treated RAW264.7 cells was found to be 115 μg/mL. To determine the inhibitory effect of the synthesized compound on the expression changes of NF-кB, the RAW264.7cells were initially induced with LPS and then treated by 15, 30 and 60 μg/mL of TZD-OCH2CH3. Realtime PCR results confirmed a strong inhibitory effect of TZD-OCH2CH3 on the expression of NF-кB inLPS-induced RAW264.7 cells (IC50 = 48 μg/mL). Overall, these findings suggested that the derivative TZDOCH2CH3 had a significant anti-inflammatory effect.

Gelidiella acerosa Compounds Target NFκB Cascade in Lung Adenocarcinoma

In carcinogenesis, increased metabolism, abnormal functioning of mitochondria, peroxisomes, aberrant cell signaling, and prolonged inflammation can result in the overproduction of reactive oxygen species (ROS). In turn, excess ROS can upregulate the expression of various signaling pathways including the MAP kinase, PI3K/Akt, and NFκB cascades in cancer. The constitutive expression of NFκB causes drug resistance in lung cancer. Hence, drugs that can enhance the antioxidant activity of enzymes and regulate the NFκB activity are of prime target to manage the drug resistance and inflammation in cancer. This study evaluated the effect of compounds present in ethyl acetate extract of Gelidiella acerosa on inflammation and on antioxidant enzymes in lung cancer. The anti-inflammatory activity was determined under in silico and in vitro conditions. The in silico analysis showed that the phyto-constituents of G. acerosa inhibit the IKBα-NFκB-p65-p50 complex in a similar way as that of doxorubicin and dexamethasone. Similarly, G. acerosa treatment enhanced the efficiency of antioxidant enzymes peroxidases and superoxide dismutase in A549 lung cancer cells. Furthermore, the results of in vitro analysis showed that G. acerosa can decrease the activation of NFκB and production of pro-inflammatory cytokines and upregulate the expression of IL 10. As inflammation causes cancer progression, the inhibition of inflammation inhibits tumorigenesis. Hence, based on the results of the study, it can be concluded that G. acerosa exerts anti-inflammatory activity by decreasing the expression of NFκB cascade and moreover, the phyto-constituents of G. acerosa may have the potential to regulate the inflammatory response.

Genetic Variations of CD40 and LTβR Genes Are Associated With Increased Susceptibility and Clinical Outcome of Non-Small-Cell Carcinoma Patients

Background

Immune system-related receptors CD40 (tumor necrosis factor receptor superfamily member 5), BAFFR (tumor necrosis factor receptor superfamily member 13C), and LTβR (tumor necrosis factor receptor superfamily member 3) play a pivotal role in non-small-cell lung cancer (NSCLC). To further evaluate their role in NSCLC, CD40 rs1883832 (T>C), BAFFR rs7290134 (A>G), and LTβR rs10849448 (A>G) single-nucleotide polymorphisms (SNPs) were investigated regarding their impact in risk and clinical outcome of NSCLC patients.

Methods

The three selected SNPs were evaluated in 229 NSCLC patients and 299 healthy controls, while CD40, BAFFR, and LTβR protein expression was assessed by immunohistochemistry in 96 tumor specimens from NSCLC patients.

Results

In total, CD40 rs1883832 was associated with NSCLC risk, with the T allele, after adjusting for cofactors, being related to increased risk (p = 0.007; OR 1.701). Moreover, the CT genotype was associated with increased risk (p = 0.024; OR 1.606) and poorer 5-year overall survival (OS) after adjusting for cofactors (p = 0.001, HR 1.829), while CC was associated with higher CD40 expression in tumorous cells (p = 0.040) and in stromal cells (p = 0.036). In addition, AA homozygotes for the LTβR rs10849448 had increased risk for NSCLC in multivariate analysis (p = 0.008; OR, 2.106) and higher LTβR membranous expression (p = 0.035). Although BAFFR rs7290134 was associated with BAFFR membranous expression (p = 0.039), BAFFR rs7290134 was not associated with neither the disease risk nor the prognosis of NSCLC patients.

Conclusions

In conclusion, CD40 rs1883832 and LTβR rs10849448 seem to be associated with increased risk for NSCLC, while CD40 rs1883832 is also associated with OS of patients with NSCLC.

The Underappreciated Role of Epithelial Mesenchymal Transition in Chronic Obstructive Pulmonary Disease and Its Strong Link to Lung Cancer

The World Health Organisation reported COPD to be the third leading cause of death globally in 2019, and in 2020, the most common cause of cancer death was lung cancer; when these linked conditions are added together they come near the top of the leading causes of mortality. The cell-biological program termed epithelial-to-mesenchymal transition (EMT) plays an important role in organ development, fibrosis and cancer progression. Over the past decade there has emerged a substantial literature that also links EMT specifically to the pathophysiology of chronic obstructive pulmonary disease (COPD) as primarily an airway fibrosis disease; COPD is a recognised strong independent risk factor for the development of lung cancer, over and above the risks associated with smoking. In this review, our primary focus is to highlight these linkages and alert both the COPD and lung cancer fields to these complex interactions. We emphasise the need for inter-disciplinary attention and research focused on the likely crucial roles of EMT (and potential for its inhibition) with recognition of its strategic place mechanistically in both COPD and lung cancer. As part of this we discuss the future potential directions for novel therapeutic opportunities, including evidence-based strategic repurposing of currently used familiar/approved medications.

NF-κB-Dependent and -Independent (Moonlighting) IκBα Functions in Differentiation and Cancer

IκBα is considered to play an almost exclusive role as inhibitor of the NF-κB signaling pathway. However, previous results have demonstrated that SUMOylation imposes a distinct subcellular distribution, regulation, NF-κB-binding affinity and function to the IκBα protein. In this review we discuss the main alterations of IκBα found in cancer and whether they are (most likely) associated with NF-κB-dependent or NF-κB-independent (moonlighting) activities of the protein.

ERα-dependent estrogen-TNFα signaling crosstalk increases cisplatin tolerance and migration of lung adenocarcinoma cells

Lung adenocarcinoma is the most common type of lung cancer in women. Our previous studies demonstrated that 17β-estradiol (E2) promoted lung adenocarcinoma cell proliferation and tumor growth through estrogen receptor ERα. Transcriptomic analysis suggested that E2 potentiated TNFα-NFκB signaling in ERα-expressing lung adenocarcinoma cells. This study further demonstrated that E2 increased TNFα receptor expression and TNFα-triggered NFκB activity in ERα-expressing cells. E2-activated ERα had no physical association with NFκB p65/p50 heterodimer but facilitated TNFα-initiated IκBα degradation, NFκB nuclear translocation, and S468/S536 phosphorylation of p65 essential for NFκB activity. While knockdown of ERα prevented E2 from boosting NFκB activity, antiestrogen ICI 182,780 stimulated NFκB activity like E2. Inhibition of GSK3β hampered E2:ERα-promoted NFκB activity and abolished S468 phosphorylation of p65, suggesting that GSK3β played a role in the E2-TNFα signaling crosstalk. In ERα-expressing cells, E2 and TNFα synergistically regulated many genes that were not typically responsive to either E2 or TNFα. Functional analysis of microarray data inferred that E2/TNFα-induced transcriptomic changes improved cell survival and movement. Viability and colony formation assays validated that E2 and TNFα together increased cisplatin tolerance of ERα-expressing cells. Wound healing assays also confirmed that E2/TNFα cotreatment increased cell migration in an ERα-dependent manner. E2/TNFα-induced dysregulation of genes such as cell survival and movement-associated genes, proto-oncogenes, metallothioneins and histone core genes was correlated with poor overall survival in patients. In summary, E2 and TNFα engaged in an ERα-dependent positive crosstalk in lung adenocarcinoma cells, consequently increasing NFκB activation, cisplatin tolerance and cell migration and worsening prognosis.

Exposures to 2,4-Dichlorophenoxyacetic acid with or without endotoxin upregulate small cell lung cancer pathway

Background

Pesticide residues in food and environment along with airborne contaminants such as endotoxins pose health risk. Although herbicide 2,4-Dichlorophenoxyacetic acid (2,4-D) has been associated with increased risk of lung cancers such as small cell lung cancer (SCLC) among agricultural workers, there are no data on the SCLC signaling pathway upon 2,4-D exposure without LPS or in combination with endotoxin.

Methods

We exposed Swiss albino mice (N = 48) orally to high (9.58 mg kg^− 1) and low (5.12 mg kg^− 1) dosages of 2,4-D dissolved in corn oil for 90 days followed by E. coli lipopolysaccharide (LPS) or normal saline solution (80 μl/animal). Lung samples and broncho-alveolar fluid (BALF) were subjected to Total histological score (THS) and total leucocyte count (TLC) and differential leucocytes count (DLC) analyses, respectively. We used microarray and bioinformatics tools for transcriptomic analyses and differentially expressed genes were analyzed to predict the top canonical pathways followed by validation of selected genes by qRT-PCR and immunohistochemistry.

Results

Total histological score (THS) along with BALF analyses showed lung inflammation following long term dietary exposure to high or low doses of 2,4-D individually or in combination with LPS. Microarray analysis revealed exposure to high dose of 2,4-D without or with LPS upregulated 2178 and 2142 and downregulated 1965 and 1719 genes, respectively (p < 0.05; minimum cut off 1.5 log fold change). The low dose without or with LPS upregulated 2133 and 2054 and downregulated 1838 and 1625 genes, respectively. Bioinformatics analysis showed SCLC as topmost dysregulated pathway along with differential expression of Itgb1, NF-κB1, p53, Cdk6 and Apaf1. Immunohistological and quantitative real time PCR (qRT-PCR) analyses also supported the transcriptomic data.

Conclusions

Taken together, the data show exposures to high and low dose of 2,4-D with/without LPS induced lung inflammation and altered pulmonary transcriptome profile with the involvement of the SCLC pathway. The data from the study provide the insights of the potential damage on lungs caused by 2,4-D and help to better understand the mechanism of this complex relation.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12995-021-00304-4.

TRIM proteins in lung cancer: Mechanisms, biomarkers and therapeutic targets

The tripartite motif (TRIM) family is defined by the presence of a Really Interesting New Gene (RING) domain, one or two B-box motifs and a coiled-coil region. TRIM proteins play key roles in many biological processes, including innate immunity, tumorigenesis, cell differentiation and ontogenetic development. Alterations in TRIM gene and protein levels frequently emerge in a wide range of tumors and affect tumor progression. As canonical E3 ubiquitin ligases, TRIM proteins participate in ubiquitin-dependent proteolysis of prominent components of the p53, NF-κB and PI3K/AKT signaling pathways. The occurrence of ubiquitylation events induced by TRIM proteins sustains internal balance between tumor suppressive and tumor promoting genes. In this review, we summarized the diverse mechanism of TRIM proteins responsible for the most common malignancy, lung cancer. Furthermore, we also discussed recent progress in both the diagnosis and therapeutics of tumors contributed by TRIM proteins.

MicroRNA-3613-5p Promotes Lung Adenocarcinoma Cell Proliferation through a RELA and AKT/MAPK Positive Feedback Loop

Aberrant activation of nuclear factor κB (NF-κB)/RELA is often found in lung adenocarcinoma (LUAD). In this study, we determined that microRNA-3613-5p (miR-3613-5p) plays a crucial role in RELA-mediated post-transcriptional regulation of LUAD cell proliferation. Expression of miR-3613-5p in clinical LUAD specimens is associated with poor prognosis in LUAD. Upregulation of miR-3613-5p promotes LUAD cell proliferation in vitro and in vivo. Our results suggested a mechanism whereby miR-3613-5p expression is induced by RELA through its direct interaction with JUN, thereby stimulating the AKT/mitogen-activated protein kinase (MAPK) pathway by directly targeting NR5A2. In addition, we also found that phosphorylation of AKT1 and MAPK3/1 co-transactivates RELA, thus constituting a RELA/JUN/miR-3613-5p/NR5A2/AKT1/MAPK3/1 positive feedback loop, leading to persistent NF-κB activation. Our findings also revealed that miR-3613-5p plays an oncogenic role in LUAD by promoting cell proliferation and acting as a key regulator of the positive feedback loop underlying the link between the NF-κB/RELA and AKT/MAPK pathways.

Metastasis-Associated Protein 2 Represses NF-κB to Reduce Lung Tumor Growth and Inflammation

Although NF-κB is known to play a pivotal role in lung cancer, contributing to tumor growth, microenvironmental changes, and metastasis, the epigenetic regulation of NF-κB in tumor context is largely unknown. Here we report that the IKK2/NF-κB signaling pathway modulates metastasis-associated protein 2 (MTA2), a component of the nucleosome remodeling and deacetylase complex (NuRD). In triple transgenic mice, downregulation of IKK2 (Sftpc-cRaf-IKK2DN) in cRaf-induced tumors in alveolar epithelial type II cells restricted tumor formation, whereas activation of IKK2 (Sftpc-cRaf-IKK2CA) supported tumor growth; both effects were accompanied by altered expression of MTA2. Further studies employing genetic inhibition of MTA2 suggested that in primary tumor growth, independent of IKK2, MTA2/NuRD corepressor complex negatively regulates NF-κB signaling and tumor growth, whereas later dissociation of MTA2/NuRD complex from the promoter of NF-κB target genes and IKK2-dependent positive regulation of MTA2 leads to activation of NF-κB signaling, epithelial-mesenchymal transition, and lung tumor metastasis. These findings reveal a previously unrecognized biphasic role of MTA2 in IKK2/NF-κB-driven primary-to-metastatic lung tumor progression. Addressing the interaction between MTA2 and NF-κB would provide potential targets for intervention of tumor growth and metastasis. SIGNIFICANCE: These findings strongly suggest a prominent role of MTA2 in primary tumor growth, lung metastasis, and NF-κB signaling modulatory functions.

Knockdown of IKKβ Inhibits Tumor Development in a Leptomeningeal Metastasis Mouse Model and Proliferation of Lung Cancer Cells

Objective

This study will explore the role of IKKβ in the leptomeningeal metastasis (LM) of lung cancer cells.

Methods

In vitro studies were conducted in mouse Lewis lung carcinoma (LLC) cells with IKKβ knockdown. Cell proliferation was explored using CCK-8 and tumor colony-forming assays. The expression of the extracellular signal-regulated kinase (ERK) signaling pathway was detected by Western blot. Tumor cell apoptosis was identified through Western blot detection of Bax and Bcl-2. The migration of tumor cells was identified by a wound healing assay. In vivo studies used an LM mouse model developed by injecting LLC cells with or without IKKβ knockdown into the cisterna magna. Mouse brain and spinal samples were sectioned for hematoxylin and eosin staining.

Results

In vitro: IKKβ knockdown inhibits tumor cell proliferation, initiates apoptosis, and attenuates cell migration. In vivo: IKKβ knockdown inhibits tumor growth in the LM mouse model. In addition, the in vitro results showed that IKKβ knockdown attenuated the expression of ERK phosphorylation in LLC cells.

Conclusion

Blocking the NF-κB signaling pathway by IKKβ knockdown in LLC cells inhibited tumor growth in the LM mouse model. IKKβ supports leptomeningeal tumor progression by promoting cancer cell proliferation and migration and inhibiting cancer cell apoptosis, and these actions may be correlated to ERK signaling.

The anti-infection drug furazolidone inhibits NF-κB signaling and induces cell apoptosis in small cell lung cancer

Targeting nuclear factor kappa B (NF-κB) signaling pathway has become a promising strategy for the development of new antitumor drugs. In this paper, we found that anti-infection drug furazolidone (FZD) could significantly inhibit NF-κB-driven luciferase activity, and FZD could markedly inhibit both of the constitutive and tumor necrosis factor-α (TNFα)-triggered phosphorylation of NF-κB p65 in small cell lung cancer (SCLC). Further studies revealed that FZD inhibited the expression of inhibitor of kappa B kinase β (IKKβ) in SCLC cells. In addition, we found that FZD had significant antitumor activities in SCLC cells. FZD could markedly suppress the cell viability of SCLC cells dose-dependently, and FZD could significantly induce the cleavages of poly ADP-ribose polymerase (PARP) and Caspase3, the biomarkers of cell apoptosis, in SCLC cells. The flow cytometry also revealed that FZD induced cell apoptosis in SCLC cells. Finally, we also found that overexpression of constitutively activated IKKβ could significantly abolish FZD-induced cell growth inhibition in SCLC cells, which further confirmed that FZD displayed its anti-SCLC activity through regulating NF-κB signaling pathway.

NF-κB inhibitors in treatment and prevention of lung cancer

Intracellular signalling pathways have provided excellent resource for drug development particularly in the development of cancer therapeutics. A wide variety of malignancies common in human exhibit aberrant NF-κB constitutive expression which results in tumorigenic processes and cancer survival in a variety of solid tumour, including pancreatic cancer, lung, cervical, prostate, breast and gastric carcinoma. Numerous evidences indicate that NF-κB signalling mechanism is mainly involved in the progression of several cancers which may intensify an enhanced knowledge on its role in disease particularly lung tumorigenesis. This has led to tremendous research in designing a variety of NF-κB antagonists with enhanced clinical applications through different approaches the most common being suppression of IκB kinase (IKK) beta activity. Many NF-κB inhibitors for lung cancer are now under clinical trials. Preliminary results of clinical trials for several of these agents include small-molecule inhibitors and monoclonal antibodies. A few combinatorial treatment therapies are currently under investigation in the clinics and have shown promise, particularly NF-κB inhibition associated with lung cancer.

Chemopreventive Property of Sencha Tea Extracts towards Sensitive and Multidrug-Resistant Leukemia and Multiple Myeloma Cells

The popular beverage green tea possesses chemopreventive activity against various types of tumors. However, the effects of its chemopreventive effect on hematological malignancies have not been defined. In the present study, we evaluated antitumor efficacies of a specific green tea, sencha tea, on sensitive and multidrug-resistant leukemia and a panel of nine multiple myelomas (MM) cell lines. We found that sencha extracts induced cytotoxicity in leukemic cells and MM cells to different extents, yet its effect on normal cells was limited. Furthermore, sencha extracts caused G2/M and G0/G1 phase arrest during cell cycle progression in CCRF/CEM and KMS-12-BM cells, respectively. Specifically, sencha-MeOH/H₂O extracts induced apoptosis, ROS, and MMP collapse on both CCRF/CEM and KMS-12-BM cells. The analysis with microarray and COMPARE in 53 cell lines of the NCI panel revealed diverse functional groups, including cell morphology, cellular growth and proliferation, cell cycle, cell death, and survival, which were closely associated with anti-tumor effects of sencha tea. It is important to note that PI3K/Akt and NF-κB pathways were the top two dominant networks by ingenuity pathway analysis. We demonstrate here the multifactorial modes of action of sencha tea leading to chemopreventive effects of sencha tea against cancer.

The Fire Within: NF-κB Involvement in Non-Small Cell Lung Cancer

Thirty-four years since its discovery, NF-κB remains a transcription factor with great potential for cancer therapy. However, NF-κB-targeted therapies have yet to find a way to be clinically translatable. Here, we focus exclusively on the role of NF-κB in non-small cell lung cancer (NSCLC) and discuss its contributing effect on cancer hallmarks such as inflammation, proliferation, survival, apoptosis, angiogenesis, epithelial-mesenchymal transition, metastasis, stemness, metabolism, and therapy resistance. In addition, we present our current knowledge of the clinical significance of NF-κB and its involvement in the treatment of patients with NSCLC with chemotherapy, targeted therapies, and immunotherapy.

Understanding the Complexity of the Tumor Microenvironment in K-ras Mutant Lung Cancer: Finding an Alternative Path to Prevention and Treatment

Kirsten rat sarcoma viral oncogene (K-ras) is a well-documented, frequently mutated gene in lung cancer. Since K-ras regulates numerous signaling pathways related to cell survival and proliferation, mutations in this gene are powerful drivers of tumorigenesis and confer prodigious survival advantages to developing tumors. These malignant cells dramatically alter their local tissue environment and in the process recruit a powerful ally: inflammation. Inflammation in the context of the tumor microenvironment can be described as either antitumor or protumor (i.e., aiding or restricting tumor progression, respectively). Many current treatments, like immune checkpoint blockade, seek to augment antitumor inflammation by alleviating inhibitory signaling in cytotoxic T cells; however, a burgeoning area of research is now focusing on ways to modulate and mitigate protumor inflammation. Here, we summarize the interplay of tumor-promoting inflammation and K-ras mutant lung cancer pathogenesis by exploring the cytokines, signaling pathways, and immune cells that mediate this process.

Adipose Tissue-Derived Mesenchymal Stem Cells Protect Against Amiodarone-Induced Lung Injury in Rats

Pulmonary fibrosis (PF) is a progressive and irreversible lung disease, characterized by poor prognosis with limited treatment options. Mesenchymal stem cells (MSCs) are multi-potent cells having the ability to self-renew and differentiate into multiple tissues, thus considered a novel treatment option. The present study aimed to investigate the possible antifibrotic effect of undifferentiated adipose tissue-derived mesenchymal stem cell (AD-MSC) therapy on PF experimentally induced in rats using amiodarone (AMD). AMD (30 mg/kg) was given orally, once daily for 12 consecutive weeks to induce lung fibrosis. Following the confirmation of lung damage with histopathological examination, AD-MSCs (2 × 10⁶ and 4 × 10⁶ undifferentiated MSCs) were injected once intravenously, followed by 2 months for treatment. AMD induced focal fibroblastic cells proliferation in the peribronchiolar tissue, as well as in between the collapsed emphysematous alveoli. Also, AMD significantly increased serum and lung homogenate fibroblast growth factor-7 (FGF7), Clara cell protein-16 (CC16), and cytokeratin -19 (CK19) levels, as well as the expression of both iNOS and NFкB in the lung alveoli. Moreover, AMD caused excessive collagen deposition and increased alpha smooth muscle actin (α-SMA) expression. All findings significantly regressed on stem cell therapy in both doses, with superior effect of the high dose, providing evidence that adipose tissue-derived MSCs could be a promising approach for the treatment of PF. Graphical Abstract.

Noncoding RNAs and Liquid Biopsy in Lung Cancer: A Literature Review

Lung cancer represents a genetically heterogeneous disease with low survival rates. Recent data have evidenced key roles of noncoding RNAs in lung cancer initiation and progression. These functional RNA molecules that can act as both oncogenes and tumor suppressors may become future biomarkers and more efficient therapeutic targets. In the precision medicine era, circulating nucleic acids have the potential to reshape the management and prognosis of cancer patients. Detecting genomic alterations and level variations of circulating nucleic acids in liquid biopsy samples represents a noninvasive method for portraying tumor burden. Research is currently trying to validate the potential role of liquid biopsy in lung cancer screening, prognosis, monitoring of disease progression, and treatment response. However, this method requires complex detection assays, and implementation of plasma genotyping in clinical practice continues to be hindered by discrepancies that arise when compared to tissue genotyping. Understanding the genomic landscape of lung cancer is essential in order to provide useful and innovative research in the age of patient-tailored therapy. In this landscape, the noncoding RNAs play a crucial role due to their target genes that dramatically influence the tumor microenvironment and the response to therapy. This article addresses present and future possible roles of liquid biopsy in lung cancer. It also discusses how the complex role of noncoding RNAs in lung tumorigenesis could influence the management of this pathology.

Thiol-Redox Regulation in Lung Development and Vascular Remodeling

Significance: Redox homeostasis is finely tuned and governed by distinct intracellular mechanisms. The dysregulation of this either by external or internal events is a fundamental pathophysiologic base for many pulmonary diseases. Recent Advances: Based on recent discoveries, it is increasingly clear that cellular redox state and oxidation of signaling molecules are critical modulators of lung disease and represent a final common pathway that leads to poor respiratory outcomes. Critical Issues: Based on the wide variety of stimuli that alter specific redox signaling pathways, improved understanding of the disease and patient-specific alterations are needed for the development of therapeutic targets. Further Directions: For the full comprehension of redox signaling in pulmonary disease, it is essential to recognize the role of reactive oxygen intermediates in modulating biological responses. This review summarizes current knowledge of redox signaling in pulmonary development and pulmonary vascular disease.

NF-κB p65 promotes ovarian cancer cell proliferation and migration via regulating mortalin

Previous studies show that mortalin, a HSP70 family member, contributes to the development and progression of ovarian cancer. However, details of the transcriptional regulation of mortalin remain unknown. We aimed to determine whether NF‐κB p65 participates in the regulation of mortalin expression in ovarian cancer cells and to elucidate the underlying mechanism. Chromatin immunoprecipitation and luciferase reporter assay were used to identify mortalin gene sequences, to which NF‐κB p65 binds. Results indicated that NF‐κB p65 binds to the mortalin promoter at a site with the sequence ‘CGGGGTTTCA’. Using lentiviral pLVX‐NF‐κB‐puro and Lentivirus‐delivered NF‐κB short hairpin RNA (shRNA), we created ovarian cancer cell lines in which NF‐κB p65 was stably up‐regulated and down‐regulated. Using these cells, we found that downregulation of NF‐κB p65 inhibits the growth and migration of ovarian cancer cells. Further experimental evidence indicated that downregulation of NF‐κB p65 reduced mortalin, and upregulation of mortalin rescued the proliferation and migration of ovarian cancer cells reduced by NF‐κB p65 knockdown. In conclusion, NF‐κB p65 binds to the mortalin promoter and promotes ovarian cancer cells proliferation and migration via regulating mortalin.

Rg3 inhibits gemcitabine-induced lung cancer cell invasiveness through ROS-dependent, NF-κB- and HIF-1α-mediated downregulation of PTX3

PTX3, a member of the long pentraxin subfamily, associated with innate immunity is indispensable for resistance to some cancer. Gemcitabine, an analog of cytosine arabinoside, has shown restrained benefits because of profound chemoresistance. The PTX3 expression on GEM in human lung cancer cells have not yet been clarified; the present study aimed to show reactive oxygen species (ROS) mediatory PTX3 expression through distinct mechanisms. Whereas ginsenoside Rg3 is a herbal medicine with strong antitumor activity. Furthermore, we tested the hypothesis; Rg3 abrogates GEM-induced production of ROS-mediated activation of Akt and extracellular signal-regulated kinase (ERK) pathways and inhibits nuclear piling-up of nuclear factor kappa B (NF-κB) and HIF-1α. On the basis of time and dose-dependent manner, our data demonstrated that GEM-induced PTX3 expression was dependent on ROS generation as it was abrogated by pretreatment of lung cancer cells with the free radical scavenger N-acetyl-l-cysteine. Our data demonstrated that PTX3 upregulation by GEM correlated with the time-dependent escalation of NF-κB and HIF-1α in the nucleus resulted from phosphorylation-induced degradation of IκBα, whereas HIF-1α upregulation was NF-κB-dependent. Increase in ROS expression in lung cancer cells on GEM treatment preceded the nuclear accumulation of NF-κB and HIF-1α and suppression of ROS diminished these effects. ERK1/2 and Akt activation mediated the effect of ROS on NF-κB and HIF-1α and their pharmacological inhibition suppressed GEM-induced PTX3. Our study findings reinforced the role regarding PTX3 signaling in GEM-induced resistance and pointed toward an unintended and undesired effect of chemotherapy and to get an active regimen; the synergy was associated with NF-κB downregulation in lung cancer.

Intranasal administration of resveratrol successfully prevents lung cancer in A/J mice

Lung cancer is the most lethal cancer in the world. About 80% of lung cancer deaths are linked to tobacco use. As a complement to tobacco control, efficient chemoprevention strategies are needed to tackle lung cancer epidemic. Resveratrol is one of the most studied natural products, notably for its cancer chemoprevention properties. However, its low oral bioavailability has often limited the translation of in vitro activities to in vivo effects. While oral administration of resveratrol effectively inhibited colorectal carcinogenesis, it failed to protect mice from chemically-induced lung carcinogenesis. Therefore, non-invasive parenteral routes must be considered to bring resveratrol to the lungs. In the present study, intranasal administration of a concentrated formulation proved to be a valid method to expose the lungs to a sufficient amount of resveratrol. This formulation was administered three times a week for 25 weeks to A/J mice having 4-[methyl(nitroso)amino]-1-(3-pyridinyl)-1-butanone-induced lung carcinogenesis. Resveratrol-treated mice showed a 27% decrease in tumour multiplicity, with smaller tumours, resulting in 45% decrease in tumour volume/mouse. In vitro investigations highlighted apoptosis as a potential mechanism of action. This study presents an effective way to overcome resveratrol low oral bioavailability, encouraging a reevaluation of its use in future clinical trials.

Roles of DNA repair enzyme OGG1 in innate immunity and its significance for lung cancer

Cytokines are pivotal mediators of the immune response, and their coordinated expression protects host tissue from excessive damage and oxidant stress. Nevertheless, the development of lung pathology, including asthma, chronic obstructive pulmonary disease, and ozone-induced lung injury, is associated with oxidant stress; as evidence, there is a significant increase in levels of the modified guanine base 7,8-dihydro-8-oxoguanine (8-oxoG) in the genome. 8-OxoG is primarily recognized by 8-oxoguanine glycosylase 1 (OGG1), which catalyzes the first step in the DNA base excision repair pathway. However, oxidant stress in the cell transiently halts enzymatic activity of substrate-bound OGG1. The stalled OGG1 facilitates DNA binding of transactivators, including NF-κB, to their cognate sites to enable expression of cytokines and chemokines, with ensuing recruitments of inflammatory cells. Hence, defective OGG1 will modulate the coordination between innate and adaptive immunity through excessive oxidant stress and cytokine dysregulation. Both oxidant stress and cytokine dysregulation constitute key elements of oncogenesis by KRAS, which is mechanistically coupled to OGG1. Thus, analysis of the mechanism by which OGG1 modulates gene expression helps discern between beneficial and detrimental effects of oxidant stress, exposes a missing functional link as a marker, and yields a novel target for lung cancer.

p52 expression enhances lung cancer progression

While many studies have demonstrated that canonical NF-κB signaling is a central pathway in lung tumorigenesis, the role of non-canonical NF-κB signaling in lung cancer remains undefined. We observed frequent nuclear accumulation of the non-canonical NF-κB component p100/p52 in human lung adenocarcinoma. To investigate the impact of non-canonical NF-κB signaling on lung carcinogenesis, we employed transgenic mice with doxycycline-inducible expression of p52 in airway epithelial cells. p52 over-expression led to increased tumor number and progression after injection of the carcinogen urethane. Gene expression analysis of lungs from transgenic mice combined with in vitro studies suggested that p52 promotes proliferation of lung epithelial cells through regulation of cell cycle-associated genes. Using gene expression and patient information from The Cancer Genome Atlas (TCGA) database, we found that expression of p52-associated genes was increased in lung adenocarcinomas and correlated with reduced survival, even in early stage disease. Analysis of p52-associated gene expression in additional human lung adenocarcinoma datasets corroborated these findings. Together, these studies implicate the non-canonical NF-κB component p52 in lung carcinogenesis and suggest modulation of p52 activity and/or downstream mediators as new therapeutic targets.

NF-kB2 Genetic Variations are Significantly Associated with Non-Small Cell Lung Cancer Risk and Overall Survival

During the last decade, a growing number of publications implicate NF-kB2 in NSCLC pathogenesis. Here, we investigated the clinical relevance of NF-kB2 single nucleotide polymorphisms (SNPs) rs7897947, rs11574852 and rs12769316 in NSCLC and their association with NF-kB2 protein and mRNA levels. Our data show that TT (rs7897947T >G) and AA (rs12769316G >A) genotypes were strongly associated with an increased risk for NSCLC (P = 0.019 and P = 0.003, respectively). Additionally, in multivariate analysis, TT (rs7897947T >G) homozygosity was associated with worse 2- and 3-year survival rates (P = 0.030 and P = 0.028, respectively), especially among patients with stages III/IV, who had worse 2, 3 and 5-year survival (P = 0.001, P = 0.022 and P = 0.035, respectively). In chemotherapy-treated patients, TT (rs12769316G >A) homozygosity was also associated with worse 2- and 3-year survival compared to G allele carriers (P = 0.006 and P = 0.014, respectively). Furthermore, rs12769316 was correlated with survival outcome of stage I and II patients (P = 0.031 and P = 0.006, respectively). Interestingly, amongst the patients who developed metastases, A allele carriers had better 5-year survival (P = 0.020). In addition, rs12769316 was associated with NF-kB2 protein (P = 0.001) and mRNA expression (P = 0.017) as well as with tumor maximum diameter (P = 0.025). Overall, this study suggests that rs7897947 and rs12769316 are involved in NSCLC susceptibility, in treatment response and in clinical outcome.

Lung Cancer Chemopreventive Activity of Patulin Isolated from Penicillium vulpinum

Lung cancer is the most lethal form of cancer in the world. Its development often involves an overactivation of the nuclear factor kappa B (NF-κB) pathway, leading to increased cell proliferation, survival, mobility, and a decrease in apoptosis. Therefore, NF-κB inhibitors are actively sought after for both cancer chemoprevention and therapy, and fungi represent an interesting unexplored reservoir for such molecules. The aim of the present work was to find naturally occurring lung cancer chemopreventive compounds by investigating the metabolites of Penicillium vulpinum, a fungus that grows naturally on dung. Penicillium vulpinum was cultivated in Potato Dextrose Broth and extracted with ethyl acetate. Bioassay-guided fractionation of this extract was performed by measuring NF-κB activity using a HEK293 cell line transfected with an NF-κB-driven luciferase reporter gene. The mycotoxin patulin was identified as a nanomolar inhibitor of TNF-α-induced NF-κB activity. Immunocytochemistry and Western blot analyses revealed that its mechanism of action involved an inhibition of p65 nuclear translocation and was independent from the NF-κB inhibitor α (IκBα) degradation process. Enhancing its interest in lung cancer chemoprevention, patulin also exhibited antiproliferative, proapoptotic, and antimigration effects on human lung adenocarcinoma cells through inhibition of the Wnt pathway.

BCSC-1 suppresses human breast cancer metastasis by inhibiting NF-κB signaling

Breast cancer suppressor candidate-1 (BCSC-1; also termed von Willebrand factor A domain containing 5A and LOH11CR2A) is a newly identified candidate tumor suppressor gene that has been implicated in several types of cancer in previous studies. However, there have been few reports about the association between BCSC-1 and human breast cancer in recent years. In the present study, the expression of BCSC-1 in breast cancer was determined by immunohistochemistry (IHC) staining of tissue microarrays and clinical tissue specimens. Subsequently, BCSC-1 gene expression was evaluated in different breast cancer cell lines by quantitative polymerase chain reaction and the MDA-MB-231 cell line was selected for further use in subsequent experiments, due to its low BCSC-1 expression. An MDA-MB-231 cell line with stable overexpression of BCSC-1 was established through transfection with plasmid containing the BCSC-1 gene, and then screening for G418 resistance. Wound-healing, migration and invasion assays were conducted to detect the effect of BCSC-1 on MDA-MB-231 cells. Furthermore, changes in matrix metalloproteinases (MMPs), osteopontin (OPN) and the nuclear factor-κB (NF-κB) pathway were detected in the current study. Additionally, stable silencing of BCSC-1 expression in MCF-7 cells was performed using a lentivirus. The results of IHC indicated that BCSC-1 is expressed at low levels in breast cancer tissues compared with in normal breast tissue. Results of the wound healing, migration and invasion assays demonstrated that BCSC-1 overexpression reduced the metastasis ability of MDA-MB-231 cells in vitro. Further research confirmed that the BCSC-1 overexpression reduced the expression levels of MMP7, MMP9 and OPN, and the phosphorylation of NF-κB p65. Furthermore, inhibition of BCSC-1 via lentivirus-mediated RNA interference revealed that the downregulation of BCSC-1 increased the invasive ability of MCF-7 cells. In summary, the results demonstrated that BCSC-1 is expressed at low levels in breast cancer tissues, and that it can suppress human breast cancer cell migration and invasion, potentially altering the expression of MMP7, MMP9, OPN, and the activity of the NF-κB pathway. Therefore, BCSC-1 may be useful as a biomarker for the treatment of breast cancer in the future.

Caffeic acid phenethyl ester down-regulates claudin-2 expression at the transcriptional and post-translational levels and enhances chemosensitivity to doxorubicin in lung adenocarcinoma A549 cells

Claudin-2 is highly expressed in human lung adenocarcinoma cells and involved in the promotion of proliferation. Here, we searched for a compound, which can decrease claudin-2 expression using lung adenocarcinoma A549 cells. In the screening using compounds included in royal jelly and propolis, the protein level of claudin-2 was dose-dependently decreased by caffeic acid phenethyl ester (CAPE), whereas the mRNA level and promoter activity were only decreased by 50 μM CAPE. These results suggest that CAPE down-regulates claudin-2 expression mediated by two different mechanisms. CAPE (50 μM) decreased the level of p-NF-κB, whereas it increased that of IκB. The CAPE-induced decrease in promoter activity of claudin-2 was blocked by the mutation in an NF-κB-binding site. The inhibition of NF-κB may be involved in the decrease in mRNA level of claudin-2. The CAPE (10 μM)-induced decrease in claudin-2 expression was inhibited by chloroquine, a lysosomal inhibitor. CAPE increased the expression and activity of protein phosphatase (PP) 1 and 2A. The CAPE-induced decrease in claudin-2 expression was blocked by cantharidin, a potent PPs inhibitor. The cell proliferation was suppressed by CAPE, which was partially rescued by ectopic expression of claudin-2. In addition, the toxicity and accumulation of doxorubicin in 3D spheroid cells were enhanced by CAPE, which was inhibited by ectopic expression of claudin-2. Taken together, CAPE down-regulates claudin-2 expression at the transcriptional and post-translational levels, and enhances sensitivity of cells to doxorubicin in 3D culture conditions. CAPE may be a useful adjunctive compound in the treatment of lung adenocarcinoma.

Co-expression of NF-κB-p65 and phosphorylated NF-κB-p105 is associated with poor prognosis in surgically resectable non-small cell lung cancer

Nuclear factor‐kappa B (NF‐κB) as a prognostic marker remains unclear in non‐small cell lung cancer (NSCLC). Here, we studied NF‐κB‐p65 (p65) expression and phosphorylated NF‐κB‐p105 (p‐p105) expression in NSCLC and correlated the finding with overall survival (OS) and clinicopathological features. A total of 186 archival samples from patients with surgically resectable NSCLC were probed with p65 and p‐p105 (Ser 932). The p65‐positive expression and p‐p105‐positive expression were defined as distinct nuclear p65 and cytoplasmic p‐p105 labelling in at least 1% of tumour cells, respectively. The positive staining of p65 alone, p‐p105 alone and co‐expression of p65 and p‐p105 were observed in 61 (32.8%), 90 (48.4%) and 35 (18.8%) patients, respectively. Co‐expression of p65 and p‐p105 but not of either p65 or p‐p105 alone was associated with a poor prognosis. Patients with co‐expression of p65 and p‐p105 had a shorter OS than others, median OS 26.5 months versus 64.1 months, HR 1.85 (95% CI: 1.18–2.91), P = 0.007. There was no statistically significant association between clinicopathological characteristics and either p65 or p‐p105 alone or co‐expression of p65 and p‐p105. This indicates that co‐expression of p65 and p‐p105 was a poor prognostic factor, and pathologic studies of NF‐κB expression could include multiple pathway components in NSCLC.

PM2.5 obtained from urban areas in Beijing induces apoptosis by activating nuclear factor-kappa B

BACKGROUND

Particulate matter (PM), which has adverse effects on citizen health, is a major air pollutant in Beijing city. PM_2.5 is an indicator of PM in urban areas and can cause serious damage to human health. Many epidemiological studies have shown that nuclear factor-kappa B (NF-κB) is involved in PM_2.5-induced cell injury, but the exact mechanisms are not well understood.

METHODS

The cytotoxic effects of PM_2.5 at 25-1600 μg/ml for 24 h were determined by MTT assay in Chinese hamster ovary cells (CHO) cells. Flow cytometry was used to determine the apoptosis rate induced by PM_2.5. The destabilized enhanced green fluorescent protein (d2EGFP) green fluorescent protein reporter system was used to determine the NF-κB activity induced by PM_2.5. The expression of pro-apoptotic Bcl-2-associated death promoter (BAD) proteins induced by PM_2.5 was determined by western blotting to explore the relationship between PM_2.5 and the NF-κB signaling pathway and to determine the toxicological mechanisms of PM_2.5.

RESULTS

PM_2.5 collected in Beijing urban districts induces cytotoxic effects in CHO cells according to MTT assay with 72.28% cell viability rates even at 200 μg/ml PM_2.5 and flow cytometry assays with 26.97% apoptosis rates at 200 μg/ml PM_2.5. PM_2.5 increases the activation levels of NF-κB, which have maintained for 24 h. 200 μg/ml PM_2.5 cause activation of NF-κB after exposure for 4 h, the activation peak appears after 13.5 h with a peak value of 25.41%. The average percentage of NF-κB activation in whole 24 h is up to 12.9% by 200 μg/ml PM_2.5. In addition, PM_2.5 decreases the expression level of the pro-apoptotic protein BAD in a concentration-dependent manner.

CONCLUSIONS

PM_2.5 induces NF-κB activation, which persists for 24 h. The expression of pro-apoptotic protein BAD decreased with increased concentrations of PM_2.5. These findings suggest that PM_2.5 plays a major role in apoptosis by activating the NF-κB signaling pathway and reducing BAD protein expression.

Chronic Cigarette Smoke Mediated Global Changes in Lung Mucoepidermoid Cells: A Phosphoproteomic Analysis

Proteomics analysis of chronic cigarette smoke exposure is a rapidly emerging postgenomics research field. While smoking is a major cause of lung cancer, functional studies using proteomics approaches could enrich our mechanistic understanding of the elusive lung cancer global molecular signaling and cigarette smoke relationship. We report in this study on a stable isotope labeling by amino acids in cell culture-based quantitative phosphoproteomic analysis of a human lung mucoepidermoid carcinoma cell line, H292 cells, chronically exposed to cigarette smoke. Using high resolution Orbitrap Velos mass spectrometer, we identified the hyperphosphorylation of 493 sites, which corresponds to 341 proteins and 195 hypophosphorylated sites, mapping to 142 proteins upon smoke exposure (2.0-fold change). We report differential phosphorylation of multiple kinases, including PAK6, EPHA4, LYN, mitogen-activated protein kinase, and phosphatases, including TMEM55B, PTPN14, TIGAR, among others, in response to chronic cigarette smoke exposure. Bioinformatics analysis revealed that the molecules differentially phosphorylated upon chronic exposure of cigarette smoke are associated with PI3K/AKT/mTOR and CDC42-PAK signaling pathways. These signaling networks are involved in multiple cellular processes, including cell polarity, cytoskeletal remodeling, cellular migration, protein synthesis, autophagy, and apoptosis. The present study contributes to emerging proteomics insights on cigarette smoke mediated global signaling in lung cells, which in turn may aid in development of precision medicine therapeutics and postgenomics biomarkers.

Cytoplasmic RAP1 mediates cisplatin resistance of non-small cell lung cancer

Cytotoxic chemotherapy agents (e.g., cisplatin) are the first-line drugs to treat non-small cell lung cancer (NSCLC) but NSCLC develops resistance to the agent, limiting therapeutic efficacy. Despite many approaches to identifying the underlying mechanism for cisplatin resistance, there remains a lack of effective targets in the population that resist cisplatin treatment. In this study, we sought to investigate the role of cytoplasmic RAP1, a previously identified positive regulator of NF-κB signaling, in the development of cisplatin resistance in NSCLC cells. We found that the expression of cytoplasmic RAP1 was significantly higher in high-grade NSCLC tissues than in low-grade NSCLC; compared with a normal pulmonary epithelial cell line, the A549 NSCLC cells exhibited more cytoplasmic RAP1 expression as well as increased NF-κB activity; cisplatin treatment resulted in a further increase of cytoplasmic RAP1 in A549 cells; overexpression of RAP1 desensitized the A549 cells to cisplatin, and conversely, RAP1 depletion in the NSCLC cells reduced their proliferation and increased their sensitivity to cisplatin, indicating that RAP1 is required for cell growth and has a key mediating role in the development of cisplatin resistance in NSCLC cells. The RAP1-mediated cisplatin resistance was associated with the activation of NF-κB signaling and the upregulation of the antiapoptosis factor BCL-2. Intriguingly, in the small portion of RAP1-depleted cells that survived cisplatin treatment, no induction of NF-κB activity and BCL-2 expression was observed. Furthermore, in established cisplatin-resistant A549 cells, RAP1 depletion caused BCL2 depletion, caspase activation and dramatic lethality to the cells. Hence, our results demonstrate that the cytoplasmic RAP1–NF-κB–BCL2 axis represents a key pathway to cisplatin resistance in NSCLC cells, identifying RAP1 as a marker and a potential therapeutic target for cisplatin resistance of NSCLC.

Biological interaction of cigarette smoking on the association between genetic polymorphisms involved in inflammation and the risk of lung cancer: A case-control study in Japan

Chronic inflammation serves an important role in lung carcinogenesis, thus genetic polymorphisms involved in this pathway may affect the risk of lung cancer. The present case-control study focused on the association between lung cancer risk and genetic polymorphisms involved in inflammatory pathways. The study comprised 462 lung cancer cases and 379 controls from Japan. The roles of interleukin 8 (IL8) rs4073, nuclear factor kappa B (NFκB) rs28362491, cytochrome b-245, alpha polypeptide (CYBA) rs4673, NAD(P) H dehydrogenase, quinone 1 (NQO1) rs1800566, nitric oxide synthase 2 and inducible (NOS2) rs2297518 polymorphisms in lung carcinogenesis were investigated. An unconditional logistic model was used to estimate the odds ratio (OR) and 95% confidence interval (CI) for the association between the genetic polymorphisms and lung cancer risk. The multiplicative and additive [relative excess risk due to interaction, attributable proportion due to interaction (AP) and synergy index (SI)] interactions with cigarette smoking were also determined. A significant association was revealed between the TT genotype of NQO1 rs1800566 and an increased risk of lung cancer (OR=1.78; 95% CI=1.14-2.79). The additive interaction evaluations between CYBA rs4673 (AP=0.50, 95% CI=0.15-0.85; SI=2.66, 95% CI=1.01-6.99) and smoking were also statistically significant. NQO1 rs1800566 was significantly associated with lung cancer risk and smoking may influence the association between CYBA rs4673 and the risk of lung cancer. Additional studies with larger control and case populations are warranted in order to confirm the CYBA rs4673-smoking association suggested by the present study.