Apoptosis In A549 Cells Research Articles

Changes in the Proteome Profile of A549 Cells Following Helichrysetin-Induced Apoptosis Suggest the Involvement of DNA Damage Response and Cell Cycle Arrest-Associated Proteins.

Our previous findings demonstrated that Helichrysetin possessed promising anti-cancer activity. It was able to induce apoptosis in the A549 cell line. However, its mechanism of action is unknown. The present study aimed to unravel possible underlying molecular mechanisms of helichrysetin-induced apoptosis in A549 (human lung carcinoma) cells using comparative quantitative proteomics (iTRAQ labeled), followed by an exhaustive bioinformatics analysis. Our results suggested that DNA damage response (DDR) and cell cycle arrest were responsible for lung cancer cell death with helichrysetin treatment. Among proteins that changed in abundance were Nrf2 and HMOX1. They are oxidative stress-related proteins and were increased in abundance. BRAT1 was also increased in abundance, suggesting an increase in DNA damage repair, indicating the occurrence of DNA damage due to oxidative stress. However, several essential DDR downstream proteins such as p-ATM, BRCA1, FANCD2, and Rb1 that would further increase DNA damage were found to be dramatically decreased in relative abundance. Cell cycle-related proteins, p53, p21, and cyclin D1, were increased while cyclin A, cyclin E, and cdk2 were decreased. This is predicted to facilitate S-phase arrest. Furthermore, excessive DNA damage and prolonged arrest would in turn result in the induction of mitochondrial-mediated apoptosis. Based on these observations, we postulate that the effects of helichrysetin were in part via the suppression of DNA damage response which led to DNA damage and prolonged cell cycle arrest. Subsequently, this event initiated mitochondrial-mediated apoptosis in A549 lung cancer cells.

Melatonin Protects Against Hyperoxia-Induced Apoptosis in Alveolar Epithelial type IICells by Activating the MT2/PI3K/AKT/ETS1 Signaling Pathway.

Hyperoxia-induced apoptosis in alveolar epithelial type II cells (AECIIs) plays a critical role in the development of bronchopulmonary dysplasia (BPD). Melatonin has been shown to improve BPD. However, the protective effect of melatonin on hyperoxia-induced apoptosis in AECIIs and the precise mechanisms involved remain unclear. Human alveolar epithelial type II A549 cells were treated with hyperoxia as an in vitro model to investigate the antiapoptotic mechanism of melatonin. CCK-8 assays were performed to investigate the viability of A549 cells. Hoechst 33,258 staining was carried out to quantify apoptosis in A549 cells. The protein expression levels of E26 oncogene homolog 1 (ETS1), Bcl-2, Bax, Bim, Wnt, β-catenin, AKT and phosphorylated AKT were measured by western blotting. LY294002, SC79 and the downregulation of ETS1, melatonin receptor 1 (MT1) and MT2 with specific siRNAs were used to investigate the role of the PI3K/AKT pathway, ETS1, MT1 and MT2 in hyperoxia-induced apoptosis in A549 cells. Melatonin prevented hyperoxia-induced apoptosis in A549 cells, and the upregulation of E26 oncogene homolog 1 (ETS1) contributed to the antiapoptotic effect of melatonin. Melatonin activated the PI3K/AKT axis, which led to ETS1 upregulation and inhibited apoptosis in hyperoxia-exposed A549 cells. Furthermore, melatonin-induced activation of the PI3K/AKT axis, upregulation of ETS1 and inhibition of apoptosis were reversed by melatonin receptor 2 (MT2) siRNA in hyperoxia-exposed A549 cells. Melatonin prevents hyperoxia-induced apoptosis by activating the MT2/PI3K/AKT/ETS1 axis in alveolar epithelial cells.

Integrated analyzes identify CCT3 as a modulator to shape immunosuppressive tumor microenvironment in lung adenocarcinoma

BackgroundChaperonin-containing tailless complex polypeptide 1 (TCP1) subunit 3 (CCT3) has tumor-promoting effects in lung adenocarcinoma (LUAD). This study aims to investigate the molecular mechanisms of CCT3 in LUAD oncogenesis.MethodsThe UALCAN databases, Human Protein Atlas (HPA) and The Cancer Genome Atlas (TCGA) data were used to analyze CCT3 expression in LUAD. Both the Wilcoxon rank-sum test and the regression model were used to investigate the connection between clinicopathologic characteristics of LUAD patients and CCT3 expression. The prognostic value of CCT3 was determined by Cox regression models, the Kaplan-Meier method and Nomogram prediction. Next, we identified the most related genes with CCT3 via GeneMANIA and String databases, and the association between CCT3 and infiltrated immune cells using single-sample Gene Set Enrichment Analysis (ssGSEA). CCT3-related pathway enrichment analysis was investigated by GSEA. Finally, CCT3 roles in cell proliferation and apoptosis of LUAD A549 cells was verified by siRNA (small interfering RNA) mediated CCT3 knockdown.ResultsCCT3 was upregulated in LUAD both in mRNA and protein levels. CCT3 overexpression was associated with clinicopathological characteristics including sex, smoking, T- and N-categories, pathological staging, and a poor prognosis of LUAD patients. GeneMANIA and String databases found a set of CCT3-related genes that are connected to the assembly and stability of proteins involved in proteostasis of cytoskeletal filaments, DNA repair and protein methylation. Furthermore, CCT3 was found to be positively correlated with the infiltrating Th2 cells (r = 0.442, p < 0.01) while negatively correlated with mast cells (r = -0.49, p < 0.01) and immature dendritic cells (iDCs, r = -0.401, p < 0.001) according to ssGSEA analyzes. The pathway analysis based on GSEA method showed that the cell cycle pathway, the protein export pathway, the proteasome pathway and the ribosome pathway are enriched in CCT3 high group, whereas the JAK/STAT pathway, B cell receptor pathway, T cell receptor pathway and toll like receptor pathway were enriched in CCT3 low group. Finally, CCT3 knockdown substantially inhibited proliferation while promoted apoptosis of A549 cells.ConclusionIntegrated analyzes identify CCT3 as a modulator to shape immunosuppressive tumor microenvironment in LUAD and therefore, a prognostic factor for LUAD.

Red light-activable biotinylated copper(II) complex-functionalized gold nanocomposite (Biotin-Cu@AuNP) towards targeted photodynamic therapy

We report the synthesis and characterization of red-light activable gold nanoparticle functionalized with biotinylated copper(II) complex of general molecular formula, [Cu(L3)(L6)]-AuNPs (Biotin-Cu@AuNP), where L3 = N-(3-((E)-3,5-di-tert-butyl-2-hydroxybenzylideneamino)-4-hydroxyphenyl)-5-((3aS,4S,6aR)-2-oxo-hexahydro-1H-thieno[3,4-d]imidazol-4-yl)pentanamide, L6 = 5-(1,2-dithiolan-3-yl)-N-(1,10-phenanthrolin-5-yl)pentanamide, which was explored for their photophysical, theoretical and photo-cytotoxic potentials. The nanoconjugate exhibits differential uptake in biotin positive and biotin negative cancer cells as well as normal cells. The nanoconjugate also shows remarkable photodynamic activity against biotin positive A549 (IC50: 13 μg/mL in red light; >150 μg/mL in dark) and HaCaT (IC50: 23 μg/mL in red light; >150 μg/mL in dark) cells under red light (600–720 nm, 30 Jcm−2) irradiation, with significantly high photo-indices (PI>15). The nanoconjugate is less toxic to HEK293T (biotin negative) and HPL1D (normal) cells. Confocal microscopy confirms preferential mitochondrial and partly cytoplasmic localization of Biotin-Cu@AuNP in A549 cells. Several photo-physical and theoretical studies reveal the red light-assisted generation of singlet oxygen (1O2) (Ф (1O2) =0.68) as a reactive oxygen species (ROS) which results in remarkable oxidative stress and mitochondrial membrane damage, leading to caspase 3/7-dependent apoptosis of A549 cells. Overall, the nanocomposite (Biotin-Cu@AuNP) exhibiting red light-assisted targeted photodynamic activity has emerged as the ideal next generation PDT agents.

Raddeanin A promotes autophagy-induced apoptosis by inactivating PI3K/AKT/mTOR pathway in lung adenocarcinoma cells.

Non-small-cell lung cancer (NSCLC) is the most common cancer in the world. Previous studies have shown that Raddeanin A (RA) exhibited distinct antitumor properties in gastric and colon cancer. This study aimed to investigate the pharmacological actions and intrinsic mechanisms of RA in NSCLC. Through the application of network pharmacology, the potential targets of RA for NSCLC therapy such as SRC, MAPK1, and STAT3 were excavated. Enrichment analyses showed that these targets were concerned with the regulation of cell death, regulation of MAPK cascade, Ras signaling pathway, and PI3K/AKT signaling pathway. Meanwhile, 13 targets of RA were identified as autophagy-related genes. Our experiment data showed that RA effectively inhibited proliferation and induced apoptosis in lung cancer cells A549. We also found that RA could induce autophagy simultaneously. Furthermore, the autophagy induced by RA had a synergistic effect with apoptosis and contributed to cell death. Additionally, RA could downregulate the activity of the PI3K/AKT/mTOR pathway. Generally, our results indicated the antitumor effect and underlying mechanisms of RA on apoptosis and autophagy in A549 cells, suggesting that RA could be used as an effective antineoplastic agent.

Chemical Compositions and Experimental and Computational Modeling of the Anticancer Effects of Cnidocyte Venoms of Jellyfish Cassiopea andromeda and Catostylus mosaicus on Human Adenocarcinoma A549 Cells.

Nowadays, major attention is being paid to curing different types of cancers and is focused on natural resources, including oceans and marine environments. Jellyfish are marine animals with the ability to utilize their venom in order to both feed and defend. Prior studies have displayed the anticancer capabilities of various jellyfish. Hence, we examined the anticancer features of the venom of Cassiopea andromeda and Catostylus mosaicus in an in vitro situation against the human pulmonary adenocarcinoma (A549) cancer cell line. The MTT assay demonstrated that both mentioned venoms have anti-tumoral ability in a dose-dependent manner. Western blot analysis proved that both venoms can increase some pro-apoptotic factors and reduce some anti-apoptotic molecules that lead to the inducing of apoptosis in A549 cells. GC/MS analysis demonstrated some compounds with biological effects, including anti-inflammatory, antioxidant and anti-cancer activities. Molecular docking and molecular dynamic showed the best position of each biologically active component on the different death receptors, which are involved in the process of apoptosis in A549 cells. Ultimately, this study has proven that both venoms of C. andromeda and C. mosaicus have the capability to suppress A549 cells in an in vitro condition and they might be utilized in order to design and develop brand new anticancer agents in the near future.

Retraction: In vivo and in vitro effects of hyperplasia suppressor gene on the proliferation and apoptosis of lung adenocarcinoma A549 Cells.

This Retraction follows an Expression of Concern relating to this article previously published by Portland Press.This article is being retracted from Bioscience Reports at the request of the Editor-in-Chief and the Editorial Board following receipt of a notification from a reader, alerting the Editorial Board to image duplications between Figures 1E and 1F in the Bioscience Reports article, and Figure 4B by Liu et al. 2019 (https://doi.org/10.1016/j.dld.2018.08.021).The Bioscience Reports paper was also flagged in Labbé et al. 2019 (https://doi.org/10.1371/journal.pone.0213266) due to incorrectly listed sequence codes. The Editorial Office approached the authors for a response to this concern and did not receive a response.The authors have been contacted with regards to the retraction, and have not responded to the Journal's queries and the concerns raised. Given the extent of the issues raised, the Editorial Board stand by the decision to retract the article.

Identification of MAP Kinase Kinase 3 as a protein target of myricetin in non-small cell lung cancer cells

Myricetin is a typical flavonol with various pharmacological effects which shows favorable biological activities in cancer. However, the underlying mechanisms and potential targets of myricetin in NSCLC (non-small cell lung cancer) cells remain unclear. First, we demonstrated that myricetin not only inhibited the proliferation, migration and invasion, but also induced apoptosis in A549 and H1299 cells in a dose-dependent manner. Then, we confirmed myricetin may play an anti-NSCLC effect through modulating MAPK-related functions and signaling pathway by Network pharmacology. Furthermore, MKK3 (MAP Kinase Kinase 3) was identified and confirmed as a potential target of myricetin by biolayer interferometry (BLI) and molecular docking, revealing that myricetin directly bound to MKK3. Moreover, three mutations (D208, L240, and Y245) of key amino acids predicted by molecular docking obviously decreased the affinity between myricetin and MKK3. Finally, enzyme activity assay was utilized to determine the effect of myricetin on MKK3 activity in vitro, and the result showed that myricetin attenuated MKK3 activity. Subsequently, myricetin decreased the phosphorylation of p38 MAPK. Furthermore, knockdown of MKK3 reduced the susceptibility of A549 and H1299 cells to myricetin. These results suggested that myricetin inhibited the growth of NSCLC cells via targeting MKK3 and influencing the downstream p38 MAPK signaling pathway. The findings revealed that MKK3 is a potential target of myricetin in the NSCLC and myricetin is considered to be a small-molecular inhibitor of MKK3, which can improve comprehension of the molecular mechanisms of myricetin pharmacological effects in cancer and further development of MKK3 inhibitors.

Knockdown of LINC00511 enhances radiosensitivity of lung adenocarcinoma via regulating miR-497-5p/SMAD3

ABSTRACT As the most common histological subtype of primary lung cancer, lung adenocarcinoma (LUAD) causes enormous cancer deaths worldwide. Radiotherapy has been frequently used in LUAD cases, and radiosensitivity is vital for LUAD therapy. This research sought to explore the genetic factors affecting radiosensitivity in LUAD and inner mechanisms. LINC00511, miR-497-5p, and SMAD3 expression in LUAD cells were detected via qRT-PCR and western blot. CCK-8 assays, colony formation, and flow cytometry assays were employed to explore the cell viability, apoptosis, and radiosensitivity in PC-9 and A549 cells. The targeting relationship between LINC00511, miR-497-5p, and SMAD3 was verified by dual luciferase reporter assay. Furthermore, xenograft experiments were performed for the in vivo verification. In conclusion, LINC00511 was overexpressed in LUAD cells, which downregulated downstream miR-497-5p expression and mediately led to SMAD3 activation. LINC00511 downregulation suppressed cell viability while enhanced apoptosis rate in LUAD cells. Also, LINC00511 and SMAD3 were overexpressed, while miR-497-5p was downregulated in LUAD cells exposed to 4Gy irradiation treatment. Moreover, LINC00511 inhibition could block SMAD3 expression and promoted the radiosensitivity both in vitro and in vivo. These findings uncover LINC00511 knockdown promoted miR-497-5p expression and subsequently led to lower SMAD3 level, which enhanced radiosensitivity in LUAD cells. LINC00511/miR-497-5p/SMAD3 axis could be of considerable potential to enhance radiosensitivity in LUAD.

SIRT3 improves alveolar epithelial cell damage caused by bronchopulmonary dysplasia through deacetylation of FOXO1.

Bronchopulmonary dysplasia (BPD) is a serious and long-term lung condition commonly observed in premature babies. Sirtuin 3 (SIRT3) has been reported to reduce pulmonary injury and pulmonary fibrosis. The present study investigated the specific role of SIRT3 in BPD by establishing hyperoxia-induced BPD rat and cell models. Hematoxylin and eosin staining was used to observe pathological changes in lung tissues. The expression levels of SIRT3 and forkhead box protein O1 (FOXO1), as well as its acetylation levels, were detected in hyperoxia-induced lung tissues and cells by Western blot analysis and reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Levels of reactive oxygen species, superoxide dismutase, and malondialdehyde were assessed by using biochemical kits. Following SIRT3 overexpression, the levels of inflammatory cytokines were assessed by RT-qPCR. Apoptosis was determined by terminal deoxynucleotidyl transferase dUTP nickend labeling (TUNEL) and Western blot analysis. Upon FOXO1 knockout, cell inflammation, oxidative stress and apoptosis were evaluated again. Compared to the control group, the SIRT3 and FOXO1 expression levels were decreased and the FOXO1 acetylation levels were increased in hyperoxia-induced lung tissues and cells. In addition, SIRT3 reduced hyperoxia-induced inflammation, oxidative stress, and apoptosis in A549 cells, and inhibited FOXO1 acetylation to activate FOXO1. However, FOXO1 knockdown reversed the effects of SIRT3 overexpression in hyperoxia-induced A549 cells. SIRT3 relieved alveolar epithelial cell damage caused by BPD via deacetylation of FOXO1, suggesting that SIRT3 could be a therapeutic target in BPD.

Combination of Network Pharmacology and In Vitro Experiments on LPSinduced A549 Cells to Explore the Molecular Mechanisms of Huanglian Jiedu Decoction Treating Pneumonia.

Huanglian Jiedu Decoction (HLJDD) was shown to exert a therapeutic effect on pneumonia for a long time in China. However, its pharmacological mechanism remains to be elucidated. The active compounds and target proteins of HLJDD were screened from TCMSP, and the pneumonia targets were obtained from GeneCards. GO, and KEGG enrichment was applied in this study. Cytoscape established networks with R-Bioconductor. The affinity between components and targets was detected by molecular docking. Finally, active ingredients and targets were selected to be verified in an inflammatory model established in LPS-induced A549 cells. CCK8 proliferation assay and western blot were performed to test the relative indicators. 102 bioactive components and 205 targets from 4 herbs in HLJDD were collected. 68 potential therapeutic targets and 55 corresponding compounds were screened to establish the networks. 4 active compounds (quercetin, wogonin, kaempferol and baicalein) and 5 hub genes (IL6, AKT1, CXCL8, CCL2 and IL1B) were then selected to make molecular docking. The results indicated that quercetin and wogonin had a better affinity with CXCL8, CCL2 or IL1B. In vitro experiments revealed that quercetin and wogonin could decrease the proliferation inhibiting and apoptosis of A549 cells injured by LPS. CXCL8, CCL2 or IL1B were downregulated after quercetin or wogonin treatment, compared with LPS-induced A549 cells (P < 0.01). The current study suggested that the mechanism of HLJDD treating pneumonia might inhibit apoptosis by targeting inflammatory factors, mainly quercetin and wogonin.

Influence of octreotide on apoptosis and metabolome expression in lipopolysaccharide-induced A549 cells

Abstract Lung cancer shows a high rate of incidence and mortality. This study aimed to investigate the influence of octreotide (OCT) on lipopolysaccharide (LPS)-induced apoptosis and metabolome expression in A549 cells. After A549 cells were treated by LPS or co-cultured with LPS and OCT, cell apoptosis was tested by flow cytometry, and gas chromatography-mass spectrometer (GC/MS) and high-performance liquid chromatography-mass spectrometer (LC/MS) were subjected to determine the differently expressed metabolites, and the interaction network was constructed. Results found that OCT promoted the apoptosis of A549 cells and significantly affected LPS-regulated cell apoptosis. Following the further investigation by orthogonal partial least squares discriminant analysis (OPLS-DA), the metabolites with different expression levels were obtained, and most of which belong to amino acids, phospholipids, organic acid, and saccharides. Fourteen components with the role of the marker metabolites included serotonin, indole, threonine, serine, glucose, phenylalanine, lactose, fumarate, 4-hydroxyphenyllactate, aspartate, asparagine, putrescine, proline, and succinate. It is indicated that OCT promotes apoptosis through five metabolism pathways and 14 key metabolism elements in A549 cells.

Targeted Overexpression of NDRG2 using Survivin Promoter Reduces Viability and Invasiveness of A549 Cell Line

Anti-tumor effects of N-myc Downstream Regulated Gene2 (NDRG2) have been demonstrated in many tumors. In the present study, NDRG2 was specifically overexpressed in lung cancer cell line using Survivin Promoter (Sur-P). Then, the effects of NDRG2 overexpression on viability, apoptosis, migration, and invasion of A549 cells were evaluated. Recombinant pAdenoVator-Sur-P-NDRG2-IRES-GFP plasmid harboring NDRG2 gene under transcriptional control of Sur-P and mock plasmid were constructed. A549 lung tumor cells and LX-2 cells (non-tumor cell line) were transfected with pAdenoVator-Sur-P-NDRG2-IRES-GFP, pAdenoVator-CMV-NDRG2-IRES-GFP, or mock plasmids. Tumor specificity of Sur-P was evaluated using fluorescent microscopy for GFP expression. The effects of NDRG2 overexpression on cell viability, apoptosis, and migration of A549 cells were measured using MTT, annexinV/7-AAD flow cytometry, and transwell migration assay, respectively. NDRG2 and matrix metalloproteinase-2 (MMP-2) expression were measured using real time-PCR. pAdenoVator-Sur-P-NDRG2-IRES-GFP transfection resulted in a huge GFP expression in A549 cells, but not in LX-2 cells. The results of real time-PCR analysis also showed that pAdenoVator-Sur-P-NDRG2-IRES-GFP transfection led to an abundant NDRG2 expression in A549 cells. NDRG2 overexpression decreased A549 cell viability through increasing cell apoptosis. In addition, migration, invasion, and MMP-2 expression decreased following NDRG2 overexpression in A549 cells. The findings indicate that the targeted overexpression of NDRG2 using Sur-P can reduce the viability and invasiveness of A549 cells, suggesting possible benefits of this approach in lung cancer therapy.

LASS2/TMSG1 overexpression inhibits proliferation and promotes apoptosis of human lung cancer A549 cells possibly by upregulating ceramide and p38 MAPK to activate a signaling cascade

To investigate the effects of LASS2/TMSG1 gene overexpression on proliferation and apoptosis of human lung cancer A549 cells and explore the possible mechanism. We examined LASS2/TMSG1 expression level in a previously constructed A549 cell line overexpressing LASS2/TMSG1 using Western blotting. The proliferation and apoptosis of the cells were detected using colony-forming assay, CCK-8 assay, Hoechst/PI double staining and flow cytometry. Fourteen nude mice were randomized into 2 groups (n=7) to receive subcutaneous injection of A549 cells with or without LASS2/TMSG1 overexpression on the back of the neck, and the cell proliferation in vivo was observed. The expression levels of p38 MAPK protein and p-p38 MAPK protein in the xenografts were detected with Western blotting. ELISA was used to detect the levels of ceramide and p38 MAPK protein in cultured A549 cell supernatants and the xenografts in nude mice. Compared with the negative control cells, A549 cells with LASS2/TMSG1 overexpression had significantly lowered proliferation ability in vitro with increased early apoptosis rate (P < 0.05), and showed obvious growth inhibition after inoculation in nude mice(P < 0.05). Western blotting showed that in both cultured A549 cells and the xenografts in nude mice, LASS2/TMSG1 gene overexpression significantly increased the expression levels of p38 MAPK protein and p-p38 MAPK protein (P < 0.05); the results of ELISA also revealed significantly increased levels of ceramide and p38 MAPK protein in the cell supernatant andxenografts as well (P < 0.05). Overexpression of LASS2/TMSG1 gene can significantly inhibit the proliferation and promote early apoptosis of human lung cancer A549 cells both in vitro and in vivo possibly by upregulating the expressions of ceramide and p38 MAPK protein to activate a signal transduction cascade.

Effect of isolated grandivittin from Ferulago trifida Boiss. (Apiaceae) on the proliferation and apoptosis of human lung cancer A549 cells.

Lung cancer is one of the deadliest cancers in the world. Introducing new promising agents can help the chemotherapeutic management of cancer. In the knowledge of oncology, plants are of special interest as a rich source of new antineoplastic and chemotherapeutic agents. Grandivittin (GRA) is one of the main constituents of Ferulago trifida Boiss. with established medicinal, phytochemical, and pharmacological properties. This study aimed to isolate and evaluate the antineoplastic potential of grandivittin and its underlying mechanisms in human lung cancer A549 cells. The viability of the A549 cells after being treated with 0.1, 0.4, 0.7, 1, and 1.3mM of GRA for three following days was measured using the MTT method. The early apoptosis and late apoptosis were assessed by fluorescence-activated cell sorter analysis through annexin V/PI staining. The expression of apoptotic agents' genes (caspase 3, caspase 9, Bcl2, Bax, and P53) was evaluated by the RT-PCR method. GRA increased apoptotic cells and decreased cell viability in a dose- and time-dependent manner, in which only 50% of cells survived at a dose of 0.7mM. The expression of Bax, P53, caspase 3, and caspase 9 genes in the A549 cells was significantly upregulated after GRA treatment compared to control cells (P < 0.05). On the other hand, Bcl2 was significantly downregulated after GRA treatment (P < 0.05). The results indicated that GRA can activate cell death in A549 lung carcinoma cells by inducing both DNA toxicity p53 and cascade-dependent pathways. Therefore, GRA may be a potential new therapeutic agent for the treatment of lung cancer.

Hyaluronic Acid-modified Liposomes for Ursolic Acid-targeted Delivery Treat Lung Cancer Based on p53/ARTS-mediated Mitochondrial Apoptosis.

Chemotherapy drugs can cause drug resistance and other problems when treating lung cancer, which leads to treatment failure. Ursolic acid (UA) is used in formulations based on traditional Chinese medicine. UA has excellent anti-tumor effects, but they are limited by solubility and non-specificity to tumor cells. To overcome these issues, we created a novel hyaluronic acid (HA)-targeted liposome system for delivering UA (HA-Lipo/UA) to explore the targeting and anti-tumor effects of UA. We constructed the HA-Lipo/UA delivery system by the thin film hydration method. The uptake and localization of UA were detected by flow cytometry and microscope. Cell proliferation of A549 cells was detected by MTT assays. Apoptosis and reactive oxygen species (ROS) expression of A549 cells were also evaluated after being treated with HA-Lipo/UA. Western blot analysis evaluated the anti-tumor mechanism of HA-Lipo/UA. HA-Lipo/UA exhibited favorable targeting of the cluster of differentiation (CD)44-overexpressing A549 cells. HA-Lipo/UA exhibited significant inhibition of the proliferation of A549 cells and induced their apoptosis compared with the corresponding monotherapies. HA-Lipo/UA induced overexpression of reactive oxygen species and upregulated expression of p53 and apoptosis-related protein in the transforming growth factor-β signaling (ARTS) pathway, which induced cytochrome-c release, activation of caspase-3, and promoted mitochondrial apoptosis in A549 cells. Taken together, these data suggested that HA-Lipo/UA could be used to target tumor cells.

Differential effects of WRAP53 transcript variants on non-small cell lung cancer cell behaviors.

The WD40-encoding RNA antisense to p53 (WRAP53) is an antisense gene of TP53 with three transcriptional start sites producing three transcript variants involved in the progression of non-small cell lung cancer. However, the mechanism by which these different transcript variants regulate non-small cell lung cancer cell behaviors is to be elucidated. Two non-small cell lung cancer cell lines, A549 cells with wild-type p53 and H1975 with mutated p53, were transfected with WRAP53-1α and WRAP53-1β siRNA. The biological effects were assessed via colony formation, cell viability, apoptosis, cell cycle, wound healing and cell invasion assays, as well as immunoblotting. Knockdown of WRAP53-1α increased the mRNA and protein levels of p53; suppressed colony formation and proliferation of A549 cells but promoted them in H1975 cells; increased the proportion of cells in the G0/G1 phase in A549 cells but decreased that in H1975 cells; and suppressed migration and invasion in A549 cells but not in H1975 cells. Conversely, knockdown of WRAP53-1β had no effect on p53 expression; promoted the growth of A549 cells but not of H1975 cells; decreased the proportion of cells in the G0/G1 phase in A549 cells but not in H1975 cells; and promoted migration and invasion in A549 cells but not in H1975 cells. Knockdown of both WRAP53-1α and WRAP53-1β promoted apoptosis in A549 cells but not in H1975 cells. WRAP53 transcript variants exerted different functions in non-small cell lung cancer cells and regulated non-small cell lung cancer cell behaviors depending on the p53 expression.

RAGE inhibition alleviates lipopolysaccharides-induced lung injury via directly suppressing autophagic apoptosis of type II alveolar epithelial cells

BackgroundAdvanced glycation end product receptor (RAGE) acts as a receptor of pro-inflammatory ligands and is highly expressed in alveolar epithelial cells (AECs). Autophagy in AECs has received much attention recently. However, the roles of autophagy and RAGE in the pathogenesis of acute lung injury remain unclear. Therefore, this study aimed to explore whether RAGE activation signals take part in the dysfunction of alveolar epithelial barrier through autophagic death.MethodsAcute lung injury animal models were established using C57BL/6 and Ager gene knockout (Ager−/− mice) mice in this study. A549 cells and primary type II alveolar epithelial (ATII) cells were treated with siRNA to reduce Ager gene expression. Autophagy was inhibited by 3-methyladenine (3-MA). Lung injury was assessed by histopathological examination. Cell viability was estimated by cell counting kit-8 (CCK-8) assay. The serum and bronchoalveolar lavage fluid (BALF) levels of interleukin (IL)-6, IL-8 and soluble RAGE (sRAGE) were evaluated by Enzyme-linked immunosorbent assay (ELISA). The involvement of RAGE signals, autophagy and apoptosis was assessed using western blots, immunohistochemistry, immunofluorescence, transmission electron microscopy and TUNEL test.ResultsThe expression of RAGE was promoted by lipopolysaccharide (LPS), which was associated with activation of autophagy both in mice lung tissues and A549 cells as well as primary ATII cells. sRAGE in BALF was positively correlated with IL-6 and IL-8 levels. Compared with the wild-type mice, inflammation and apoptosis in lung tissues were alleviated in Ager−/− mice. Persistently activated autophagy contributed to cell apoptosis, whereas the inhibition of autophagy by 3-MA protected lungs from damage. In addition, Ager knockdown inhibited LPS-induced autophagy activation and attenuated lung injury. In vitro, knockdown of RAGE significantly suppressed the activation of LPS-induced autophagy and apoptosis of A549 and primary ATII cells. Furthermore, RAGE activated the downstream STAT3 signaling pathway.ConclusionRAGE plays an essential role in the pathogenesis of ATII cells injury. Our results suggested that RAGE inhibition alleviated LPS-induced lung injury by directly suppressing autophagic apoptosis of alveolar epithelial cells.

Anethole attenuates lung cancer progression by regulating the proliferation and apoptosis through AKT and STAT3 signaling

Background: The main constituent of fennel, anethole, exerts beneficial effects in many diseases, including antiproliferative and tumoricidal capacities. This study aimed to investigate the effect of anethole on the human non-small cell lung cancer (NSCLC) cell line, A549, and the related molecular mechanisms.&#x0D; Methods: The proliferation was assessed by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and colony formation assays. Apoptosis situation was determined using fluorescence-activated cell sorting and DNA fragmentation assay combined with immunoblotting assay probing-related protein expression. Phosphoinositide 3-kinases-protein kinase B (PI3K-AKT) and signal transducer and activator of transcription 3 (STAT3) signaling proteins were evaluated using immunoblotting. Xenograft model was constructed to determine the tumor volume and weight and to evaluate the expression of Ki67 via immunohistochemistry and cleaved caspase 3 via immunoblotting.&#x0D; Results: Anethole inhibited proliferation and clonal growth of A549 cells. The promotion of A549 cell apoptosis by anethole was evidenced by increased apoptotic ratio, abundant DNA fragments, and caspase-3 activation. Key proteins in PI3K-AKT and STAT3 signaling pathways were decreased in anethole group. Additionally, xenografted tumors in anethole group retarded with decreased Ki67 and increased cleaved caspase 3 expression.&#x0D; Conclusions: Anethole induced tumor cell apoptosis and retarded cell proliferation. AKT and STAT3 signaling pathways might be involved in the effects of anethole. Our findings highlight the feasibility of anethole in the treatment of lung cancer.

Anethole attenuates lung cancer progression by regulating the proliferation and apoptosis through AKT and STAT3 signaling

Background: The main constituent of fennel, anethole, exerts beneficial effects in many diseases, including antiproliferative and tumoricidal capacities. This study aimed to investigate the effect of anethole on the human non-small cell lung cancer (NSCLC) cell line, A549, and the related molecular mechanisms.&#x0D; Methods: The proliferation was assessed by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and colony formation assays. Apoptosis situation was determined using fluorescence-activated cell sorting and DNA fragmentation assay combined with immunoblotting assay probing-related protein expression. Phosphoinositide 3-kinases-protein kinase B (PI3K-AKT) and signal transducer and activator of transcription 3 (STAT3) signaling proteins were evaluated using immunoblotting. Xenograft model was constructed to determine the tumor volume and weight and to evaluate the expression of Ki67 via immunohistochemistry and cleaved caspase 3 via immunoblotting.&#x0D; Results: Anethole inhibited proliferation and clonal growth of A549 cells. The promotion of A549 cell apoptosis by anethole was evidenced by increased apoptotic ratio, abundant DNA fragments, and caspase-3 activation. Key proteins in PI3K-AKT and STAT3 signaling pathways were decreased in anethole group. Additionally, xenografted tumors in anethole group retarded with decreased Ki67 and increased cleaved caspase 3 expression.&#x0D; Conclusions: Anethole induced tumor cell apoptosis and retarded cell proliferation. AKT and STAT3 signaling pathways might be involved in the effects of anethole. Our findings highlight the feasibility of anethole in the treatment of lung cancer.