Lung Cancer Cell Line H1299 Research Articles

Discovery of 4-(4-(3-(1-(2-(piperidin-1-yl)ethyl)-1H-benzo[d]imidazole-2-yl)isoxazol-5-yl)phenyl)morpholine as a novel c-Myc inhibitor against lung cancer in vitro and in vivo

The critical role of c-Myc as a driving factor in the development and progression of lung cancer establishes it as a pivotal target for anti-lung cancer therapeutic research. In our previous study, we reported on the discovery of D347–2761, a novel small-molecule inhibitor that specifically targets the unstable domain of c-Myc and disrupts the c-Myc/Max heterodimer. To enhance targeted therapies further, we conducted an extensive structural analysis and designed a series of innovative benzimidazole derivatives. The cytotoxic activities of these compounds were assessed using the CCK-8 assay, revealing that compound A1 displayed IC50 values of 6.32 μM and 11.39 μM against the A549 and NCI–H1299 lung cancer cell lines, respectively, while compound A5 exhibited IC50 values of 4.08 μM and 7.86 μM against the same cell lines. Our findings revealed that compounds A1 and A5 exhibited potent anticancer activity by disrupting the interaction between c-Myc and Max proteins, leading to the downregulation of c-Myc protein levels and induction of apoptosis through apoptotic pathways. Notably, compound A5 demonstrated superior inhibitory capacity compared to other compounds tested. Furthermore, in a syngeneic tumor model, compound A5 exhibited excellent efficacy with a tumor growth inhibition rate reaching up to 76.4 %, accompanied by a significant reduction in c-Myc protein expression levels. Therefore, compound A5 holds promise as a potential agent for targeting c-Myc in anti-lung cancer therapy.

Synthesis, characterisation of ZnO@PDA@Ag nanocomposite: Mechanistic interaction with BSA, photodegradation activity & in vitro cytotoxicity assay on H1299 lung cancer cell line

Despite advancements in diagnosis and therapeutic, cancer retains to be a greatest cause of fatality and economic damage to the world. Metallic nanoparticles have grabbed attention particularly in the field of medicine attributed to their noteworthy biological and catalytic properties, offering significant progress. The work aimed to create a novel biocompatible ‘Silver doped Polydopamine coated Zinc-Oxide nanocomposite’ and investigate its efficacy in treating H1299 lung cancer cells as well as water remediation. In this study, a ‘ZnO@PDA@Ag’ Nanocomposite was synthesised using co-precipitation method and was further characterised using DLS, FESEM-EDX, P-XRD, XPS, TEM and FT-IR techniques. The mechanistic interaction with blood protein, suggested strong binding interactions and notable structural changes in BSA upon exposure to the nanocomposite. The photocatalytic properties evaluated against the Rhodamine B Dye under UV–Visible light irradiation demonstrated a photodegradation of~49.77 % within 120 min for 60 μg/mL of the used nanocomposite. Herein, we present an evaluation of anticancer bioactivity of ZnO@PDA@Ag nanoparticles using MTT assay against the H1299 lung cancer cell line and its IC50 was estimated to be (42.42 ± 4) μg/mL. The cytotoxicity was enhanced through immobilization of Silver (Ag) metal on ZnO@PDA. Moreover, the hemolysis experiment was also conducted to demonstrate the biocompatibility of nanoparticle to human red blood cells. As a result, the successfully created biocompatible nanomaterial may be useful as an efficient drug-delivery system against cancer cells.

Adunctin E from Conamomum rubidum Induces Apoptosis in Lung Cancer via HSP90AA1 Modulation: A Network Pharmacology and In Vitro Study.

Lung cancer stands out as a leading cause of death among various cancer types, highlighting the urgent need for effective anticancer drugs and the discovery of new compounds with potent therapeutic properties. Natural sources, such as the Conamomum genus, offer various bioactive compounds. Adunctin E (AE), a dihydrochalcone derived from Conamomum rubidum, exhibited several pharmacological activities, and its potential as an anticancer agent remains largely unexplored. Thus, this study aimed to elucidate its apoptotic-inducing effect and identify its molecular targets. The network pharmacology analysis led to the identification of 71 potential targets of AE against lung cancer. Subsequent gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Reactome pathway enrichment analyses revealed the involvement of these targets in cancer-associated signaling pathways. Notably, HSP90AA1, MAPK1, and PIK3CA emerged as key players in apoptosis. In silico molecular docking and dynamic simulations suggested a strong and stable interaction between AE and HSP90AA1. In vitro experiments further confirmed a significant apoptotic-inducing effect of AE on lung cancer cell lines A549 and H460. Furthermore, immunoblot analysis exhibited a substantial decrease in HSP90AA1 levels in response to AE treatment. These findings support the potential anticancer activity of AE through the HSP90AA1 mechanism, underscoring its promise as a novel compound worthy of further research and development for anti-lung cancer therapy.

Unveiling the antitumor synergy between pazopanib and metformin on lung cancer through suppressing p-Akt/ NF-κB/ STAT3/ PD-L1 signal pathway

Pazopanib, an inhibitor of the VEGF receptor tyrosine kinase, has demonstrated significant antitumor effects in lung cancer. However, its application as a standard treatment for this type of cancer is limited by its drug resistance and toxicity. Metformin has the potential to combat lung cancer by modifying the tumor’s immune microenvironment.In this study, we investigated the potential antitumor effects and the associated underlying molecular mechanisms of the combination of pazopanib and metformin in lung cancer. In vitro studies were conducted using the A549 and H460 lung cancer cell lines, whereas urethane-induced lung cancer-bearing mice were used for in vivo assessments. The urethane-induced mice received oral administration of pazopanib (50 mg/kg) and/or metformin (250 mg/kg) for a duration of 21 days.The results indicated that the MTT assay demonstrated a combined cytotoxic effect of the pazopanib/metformin combination in H460 and A549 cells, as evidenced by CI and DRI analyses. The observed increase in annexin V levels and the corresponding increase in Caspase-3 activity strongly suggest that this combination induced apoptosis.Furthermore, the pazopanib/metformin combination significantly inhibited the p-Akt/NF-κB/IL-6/STAT3, HIF1α/VEGF, and TLR2/TGF-β/PD-L1 pathways while also increasing CD8 expression in vivo. Immunohistochemical analysis revealed that these antitumor mechanisms were manifested by the suppression of the proliferation marker Ki67. In conclusion, these findings revealed that metformin augments the antitumor efficacy of pazopanib in lung cancer by simultaneously targeting proliferative, angiogenic, and immunogenic signaling pathways, metformin enhances the antitumor effectiveness of pazopanib in lung cancer, making it a promising therapeutic option for lung cancer.

Synergistic anticancer effects of SMYD2 inhibitor BAY-598 and doxorubicin in non-small cell lung cancer

BackgroundNon-small cell lung Cancer (NSCLC) persists as a lethal neoplastic manifestation, exhibiting a diminished 5-year survival rate, partially attributable to chemotherapeutic resistance. This investigative endeavor aimed to elucidate the synergistic antineoplastic effects and underlying mechanisms of the SMYD2 inhibitor BAY-598 and the chemotherapeutic agent doxorubicin (DOX) in NSCLC. MethodsThe human non-small cell lung cancer cell lines A549 and H460 were subjected to treatment regimens involving BAY-598 and/or DOX. Cellular viability, apoptotic events, invasive capacity, and migratory potential were evaluated through the implementation of CCK-8 assays, flow cytometric analyses, and Transwell assays, respectively. Protein expression levels were quantified via Western blot analyses. An in vivo xenograft murine model was established to assess therapeutic efficacy. ResultsBAY-598 and DOX synergistically suppressed the viability, invasiveness, and migratory capabilities of NSCLC cells. Co-treatment Promoting cell apoptosis and cell cycle arrest. Additionally, Furthermore, co-administration significantly inhibited cell migration and invasion. Mechanistic studies revealed coordinately inhibited JAK-STAT signaling upon combination treatment. In vivo study further validated the synergistic antitumor efficacy of BAY-598 and DOX against NSCLC xenografts. ConclusionsOur findings demonstrate that BAY-598 potentiates the anti-cancer effects of DOX in non-small cell lung cancer cells by modulating the JAK/STAT signaling pathway as a synergistic strategy. The combination holds promise as an emerging therapeutic strategy for NSCLC. Further optimization and validation are warranted to promote its translational potential.

Label-Free Measurement of CD63 Positive Extracellular Vesicles Using Terahertz Chemical Microscopy.

Extracellular vesicles (EVs) are small cellular organelles involved in intracellular signaling and cell-to-cell interactions. Recent studies suggested that exosomes may have potential applications in the diagnosis and treatment of cancer and neurodegenerative diseases. In this study, extracellular vesicles of the human nonsmall cell lung cancer cell line H1299 and the unlabeled antiCD63 antibody were imaged using a new label-free terahertz chemical microscopy (TCM) technique to detect changes in the terahertz wave amplitude. To verify the high specificity of the protein biomarkers and the sensitivity of the biosensor surface, we also confirmed the selective binding of the antibody to the antigen, bovine serum albumin, and cancer cells. We also performed real-time measurements of the interaction between EVs from the H1299 cell and the antiCD63 antibody, which showed that the amount of change in the terahertz intensity increased with increasing concentration and the time to saturation decreased. Finally, to reuse the used biosensors (sensing plates), plasma-oxygen cleaning was used, and the activity of the biosensor surface was confirmed by terahertz microscopy and atomic force microscopy and was found to be reusable after less than 3 min of cleaning. Consequently, terahertz chemical microscopy was able to detect the presence or absence of antigen-antibody binding and its reaction rate and binding strength.

DNMT1/miR-152-3p/SOS1 signaling axis promotes self-renewal and tumor growth of cancer stem-like cells derived from non-small cell lung cancer

BackgroundCSLCs(Cancer stem cell-like cells), which are central to tumorigenesis, are intrinsically influenced by epigenetic modifications. This study aimed to elucidate the underlying mechanism involving the DNMT1/miR-152-3p/SOS1 axis in regulating the self-renewal and tumor growth of LCSLCs (lung cancer stem-like cells).Materials and methodsTarget genes of miR-152-3p were predicted using TargetScan Human 8.0. Self-renewal and tumor growth of LCSLC were compared in suspension-cultured non-small cell lung cancer (NSCLC) cell lines H460 and A549 cell-derived globe cells. Functional effects of the DNMT1/miR-152-3p/SOS1 axis were assessed through gain-of-function experiments in vitro and in vivo. Additionally, luciferase reporter assays were employed to analyze the interaction among DNMT1, miR-152-3p, and SOS1.ResultsOur findings highlight a negative interaction between DNMT1 and miR-152-3p, resulting in reduced miR-152-3p level. This, in turn, leads to the alleviation of the inhibitory effect of miR-152-3p on the target gene SOS1, ultimately activating SOS1 and playing an essential role in self-renewal and tumor growth of LCSLC. However, the alteration of SOS1 does not affect DNMT1/miR-152-3p regulation. Therefore, it is reasonable to infer that the DNMT1/miR-152-3p negative feedback loop critically sustains self-renewal and tumor growth of LCSLC through SOS1.ConclusionsThis study reveals a novel mechanism underpinning self-renewal and tumor growth of CSLC (cancer stem cell) in NSCLC and identifies potential therapeutic targets for NSCLC treatment.

Overexpression of PIK3CG in Cancer Cells Promotes Lung Cancer Cell Migration and Metastasis Through Enhanced MMPs Expression and Neutrophil Recruitment and Activation.

Metastasis is a major cause of death in lung cancer. The aim of this study is to analyze the role and mechanism of PI3K catalytic subunit gamma (PIK3CG, also known as p110γ) in lung cancer cell migration and metastasis. Knockdown (KD) and overexpression (OE) of PIK3CG expression in lung cancer cell lines A549 and H1299 in vitro cultured was achieved. Two PIK3CG-specific inhibitors, Eganelisib and CAY10505, were used to treat A549 and H1299 cells. An experimental lung metastasis mouse model was constructed using tail vein injection of LLC cells. Finally, a co-culture system was established using Transwell chambers. Compared with the NC group, the number of cells that completed migration and the expression levels of matrix metalloproteinases (MMPs) were significantly reduced in the KD group and Eganelisib and CAY10505 treatment groups, while the number of cells that migrated successfully and the expression levels of MMPs were significantly increased in the OE group. Lung tissues of mice injected with PIK3CG-stabilized overexpressed LLC cells showed more pronounced lung cancer growth, lung metastatic nodules, neutrophil infiltration and MMPs expression. Co-culture with neutrophils, soluble extracts of neutrophils and cathepsin G all promoted the migration of lung cancer cells. PIK3CG overexpression in tumor cells significantly promoted the migration and metastasis of lung cancer cell.

Abstract LB049: Isoharpontigenin inhibits migration and invasion of lung cancer cells through MEG3/EGFR pathway

Abstract Lung cancer is the second most common cancer in both men and women in the United States. Even though treatments including chemotherapy, targeted therapy, and immunotherapy are available, lung cancer has been the leading cause of cancer deaths. The discovery and evaluation of new alternative medications targeting lung cancer are tremendously important for reducing lung cancer mortality. Phytochemicals are very desirable chemotherapeutic agents because of their greater safety profile. Isorhapontigenin (ISO), one of the oral bioavailable dietary stilbenes, can be found in various natural resources. Our result showed that ISO treatment suppressed the invasion and migration of human lung cancer cell lines A549, H23, and H1299 cells. Long non-coding RNA Maternally Expressed Gene 3 (MEG3), a tumor suppressor, was downregulated or lost in various primary human tumor tissues and cancer cell lines. The low expression of MEG3 is correlated with poor prognosis in non-small cell lung cancer (NSCLC). Our results showed that ISO treatment elevated MEG3 levels in these lung cancer cell lines. One of the major genetic causes of lung cancer is mutations in the epidermal growth factor receptor (EGFR) receptor tyrosine kinase, resulting in activation of EGFR which activates several signaling pathways involved in cell proliferation, drug sensitivity, and angiogenesis. Our results showed that ISO decreased the phosphorylation and protein levels of EGFR in A549 cells. Hypoxia-inducible factor-1α (HIF-1α), a transcription factor, regulates the activation of several genes involved in cell proliferation, angiogenesis, invasion, and metastasis. Our results showed that ISO decreased HIF-1α protein levels. Overexpression of MEG3 reduced p-EGFR and HIF-1α, indicating MEG3 negatively regulated EGFR and HIF-1α. Our data also showed that inhibition of EGFR by its tyrosine inhibitor decreased HIF-1α, suggesting that EGFR positively regulates HIF-1α. In cancer cells, Epithelial-Mesenchymal Transition(EMT) endows cells with increased invasiveness and tumor-initiating capacity, contributing to metastasis and resistance to therapeutics. Slug, one of the EMT transcription factors maintains cell plasticity during carcinogenesis. Our results showed that ISO treatment decreased Slugprotein levels in A549 and H23 cells. Transcription factor SOX2 regulates cancer cell proliferation, EMT, migration, invasion, metastasis, tumor initiation, cancer stem cell formation as well as resistance to apoptosis and therapy. Our results showed that ISO decreased SOX2 expression. Knockdown of MEG3 increased the expressions of Slug and SOX2, indicating that MEG3 negatively regulates Slug and SOX2. In conclusion, ISO elevated MEG3, inhibiting EGFR, HIF-1α, Slug, and SOX2, suppressing the migration and invasion of lung cancer cells. Citation Format: Sophia Shi, Zhuo Zhang, Jingxia Li, Huailu Tu, Max Costa. Isoharpontigenin inhibits migration and invasion of lung cancer cells through MEG3/EGFR pathway [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB049.

Chemical constituents of Penicillium ferraniaense GE-7 and their cytotoxicities

Phytochemical investigation on the plant endophytic fungus Penicillium ferraniaense GE-7 led to the isolation of 18 compounds including one new α-pyrone derivative, peniferranige A (1). The structure including the absolute configuration of compound 1 was elucidated by NMR, HRMS, and ECD data. Demethoxyfumitremorgin C (16) and meleagrin (17) possessed moderate activities against the human lung cancer cell line H1975 with IC50 values of 28.52 ± 1.07 and 13.94 ± 1.92 μM, respectively.

Functionalized gold nanoparticles coated with bacterial alginate and their antibacterial and anticancer activities

Abstract Gold nanoparticles (Au-NPs) have several uses for nanobiotechnologists because of their beneficial biomedical properties. Alginates have various biomedical and industrial applications. The aim of this study is to extract alginate from Azotobacter chroococcum, synthesize chemical Au-NPs (Ch/Au-NPs), and load the NPs with the extracted alginate to form Azotobacter alginate gold nanocomposites (Azto/Alg-Au-NCMs). The Ch/Au-NPs and Azto/Alg-Au-NCMs were characterized by UV-spectroscopy, Fourier-transform infrared (FT-IR) spectroscopy, energy-dispersive spectroscopy (EDS), X-ray diffraction (XRD), thermogravimetric analysis (TGA), zeta potential, and transmission electron microscopy (TEM). The anticancer activities were determined using the breast cancer cell line MCF-7, human lung cancer cell line H1299, and Vero cell line. The results obtained by UV-spectroscopy exhibited a surface plasmon resonance that was clearly noticeable at 530 nm, and the EDS analysis proved that gold was present in percentages of 50.11 and 28.08 in the Ch/Au-NPs and Azto/Alg-Au-NCMs, respectively. There were several similarities between the alginic acid and the alginate extracted from A. chroococcum, and small modifications were proved by FT-IR spectroscopy. Negative charges were shown by the zeta potential. Crystalline and cubic NPs were shown by XRD analysis and TEM. TGA demonstrated the purity of the Ch/Au-NPs and the existence of organic compounds in the Azto/Alg-Au-NCMs. Both the Ch/Au-NPs and Azto/Alg-Au-NCMs had antibacterial activities against Staphylococcus aureus ATCC 25923, Proteus mirabilis, Enterobacter sp., and Pseudomonas aeruginosa and possessed anticancer activities against MCF-7 and H1299.

Synthesis and characterization of Fe3O4@SiO2@PDA@Ag core–shell nanoparticles and biological application on human lung cancer cell line and antibacterial strains

Novel magnetic and metallic nanoparticles garner much attention of researchers due to their biological, chemical and catalytic properties in many chemical reactions. In this study, we have successfully prepared a core–shell Fe3O4@SiO2@PDA nanocomposite wrapped with Ag using a simple synthesis method, characterised and tested on small cell lung cancer and antibacterial strains. Incorporating Ag in Fe3O4@SiO2@PDA provides promising advantages in biomedical applications. The magnetic Fe3O4 nanoparticles were coated with SiO2 to obtain negatively charged surface which is then coated with polydopamine (PDA). Then silver nanoparticles were assembled on Fe3O4@SiO2@PDA surface, which results in the formation core–shell nanocomposite. The synthesised nanocomposite were characterized using SEM-EDAX, dynamic light scattering, XRD, FT-IR and TEM. In this work, we report the anticancer activity of silver nanoparticles against H1299 lung cancer cell line using MTT assay. The cytotoxicity data revealed that the IC50 of Fe3O4@SiO2@PDA@Ag against H1299 lung cancer nanocomposites cells was 21.52 µg/mL. Furthermore, the biological data of nanocomposites against Gram-negative ‘Pseudomonas aeruginosa’ and Gram-positive ‘Staphylococcus aureus’ were carried out. The range of minimum inhibitory concentration was found to be 115 µg/mL where gentamicin was used as a standard drug. The synthesized AgNPs proves its supremacy as an efficient biomedical agent and AgNPs may act as potential beneficial molecule in lung cancer chemoprevention and antibacterial strains.

Natural Product Cordycepin (CD) Inhibition for NRP1/CD304 Expression and Possibly SARS-CoV-2 Susceptibility Prevention on Cancers.

NRP1/CD304 is a typical membrane-bound co-receptor for the vascular endothelial cell growth factor (VEGF), semaphorin family members, and viral SARS-CoV-2. Cordycepin (CD) is a natural product or active gradient from traditional Chinese medicine (TCM) from Cordyceps militaris Link and Ophiocordyceps sinensis (Berk.). However, NRP1 expression regulation via CD in cancers and the potential roles and mechanisms of SARS-CoV-2 infection are not clear. In this study, online databases were analyzed, Western blotting and quantitative RT-PCR were used for NRP1 expression change via CD, molecular docking was used for NRP/CD interaction, and a syncytial formation assay was used for CD inhibition using a pseudovirus SARS-CoV-2 entry. As a result, we revealed that CD inhibits NRP1 expressed in cancer cells and prevents viral syncytial formation in 293T-hACE2 cells, implying the therapeutic potential for both anti-cancer and anti-viruses, including anti-SARS-CoV-2. We further found significant associations between NRP1 expressions and the tumor-immune response in immune lymphocytes, chemokines, receptors, immunostimulators, immune inhibitors, and major histocompatibility complexes in most cancer types, implying NRP1's roles in both anti-cancer and anti-SARS-CoV-2 entry likely via immunotherapy. Importantly, CD also downregulated the expression of NRP1 from lymphocytes in mice and downregulated the expression of A2AR from the lung cancer cell line H1975 when treated with CD, implying the NRP1 mechanism probably through immuno-response pathways. Thus, CD may be a therapeutic component for anti-cancer and anti-viral diseases, including COVID-19, by targeting NRP1 at least.

Using long-read CAGE sequencing to profile cryptic-promoter-derived transcripts and their contribution to the immunopeptidome.

Recent studies have shown that the noncoding genome can produce unannotated proteins as antigens that induce immune response. One major source of this activity is the aberrant epigenetic reactivation of transposable elements (TEs). In tumors, TEs often provide cryptic or alternate promoters, which can generate transcripts that encode tumor-specific unannotated proteins. Thus, TE-derived transcripts (TE transcripts) have the potential to produce tumor-specific, but recurrent, antigens shared among many tumors. Identification of TE-derived tumor antigens holds the promise to improve cancer immunotherapy approaches; however, current genomics and computational tools are not optimized for their detection. Here we combined CAGE technology with full-length long-read transcriptome sequencing (long-read CAGE, or LRCAGE) and developed a suite of computational tools to significantly improve immunopeptidome detection by incorporating TE and other tumor transcripts into the proteome database. By applying our methods to human lung cancer cell line H1299 data, we show that long-read technology significantly improves mapping of promoters with low mappability scores and that LRCAGE guarantees accurate construction of uncharacterized 5' transcript structure. Augmenting a reference proteome database with newly characterized transcripts enabled us to detect noncanonical antigens from HLA-pulldown LC-MS/MS data. Lastly, we show that epigenetic treatment increased the number of noncanonical antigens, particularly those encoded by TE transcripts, which might expand the pool of targetable antigens for cancers with low mutational burden.

Disclosing Potential Therapeutic Targets Associated With Osimertinib Resistance in the Non-small Cell Lung Cancer Cell Line H1975.

Osimertinib, a third-generation epidermal growth factor receptor tyrosine kinase inhibitor, is a highly effective and valuable treatment option for advanced non-small cell lung cancer (NSCLC) patients with EGFR mutations, such as T790M. However, acquired resistance ultimately limits its clinical application. In this study, we aimed to identify potential targets for overcoming osimertinib resistance. The H1975/OSI cell line was induced in vitro through intermittent induction. Cell activity was measured using a cell counting kit-8 assay. Uni-omics and multi-omics analyses were conducted on the transcriptomic and proteomic (4D label-free) expression profiles, which involved differential expression analysis, GO functional annotation and KEGG pathway enrichment analysis, as well as correlation analysis of transcription factors and PPI network. H1975/OSI cells showed resistance towards osimertinib with IC50 values approximately 5.25-fold higher than H1975 cells. A total of 2519 genes were found to be differentially expressed genes (DEGs) and 1533 proteins were found to be differentially abundant proteins (DAPs). Furthermore, 147 genes that were differentially expressed at both the transcription and protein levels (TPGs) were identified as being differentially expressed in both the transcriptome and proteome. It was revealed that many pathways related to the structure and function of ribosomes, as well as metabolites, were altered. The highest connectivity genes of 147 TPGs included NOP56, DDX21, PDCD11, CCNB1, and TOP2A. The hub genes of the transcriptional regulatory network included DDX21, KPNA2, DDX5, BRCA1, LMNB1, and HIF1A. Collectively, our high-throughput analysis uncovered functional properties that interacted with gene signatures of H1975/OSI cells, and highlighted certain pathways and eleven hub genes that may be the potential targets for improving clinical osimertinib resistance.

Release kinetics approach of stimuli-responsive mesoporous silica nanocarriers: pH-sensitive linker versus pH-sensitive framework

Silica-based stimuli-responsive nanomaterials have attracted significant attention in the field of drug delivery because they can achieve controlled release of anticancer drugs. For this, a gatekeeper is usually used, thus avoiding unwanted leakage at pH 7.4, while modulating the release under more acidic pH conditions in the tumor cell microenvironment. To optimize the efficiency of these nanostructures, it is crucial to study the release kinetics of anticancer drugs, predict their behavior, and modify the transport process mechanism. In the present study, we synthesized and characterized two types of pH-responsive mesoporous silica nanocarriers, which have transferrin conjugates on the surface serving as a gatekeeper. One nanocarrier was a conventional mesoporous silica nanoparticle (MSN) with transferrin attached through a pH-sensitive linker (MSN-Tf), while the other had a pH-sensitive diimine bridge in its framework, giving it degradable characteristic (dMSN-Tf). The use of conventional mathematical models and a three-parameter model that considers the drug-matrix interaction allowed the evaluation and elucidation of the different mechanisms involved in the kinetics of doxorubicin release from both materials at pH 7.4 and pH 5.0. The change in the kinetics of doxorubicin release from zero-order to first-order when it is in a degradable system such as dMSN-Tf, can be very useful for rapid drug delivery in acidic media such as inside cancer cells. Cell viability experiments in lung cancer cell lines A549 and H1299, showed enhanced anticancer activity by the nanomaterial with the pH-sensitive framework compared to the material that has a pH-sensitive linker. Overall, these findings provide important insights for optimizing the delivery of anticancer drugs.

Metformin induces ferroptosis through the Nrf2/HO-1 signaling in lung cancer

BackgroundMetformin is the most frequently prescribed medication for the treatment of type II diabetes mellitus and has played an anti-tumor potential in a variety of cancer types. Metformin can inhibit the growth of many cancer cells through various mechanisms, including ferroptosis. However, it is still unclear whether metformin can induce ferroptosis in lung cancer.MethodsThis study evaluated the anti-tumor effect of metformin by detecting the levels of oxidative stress factors, the levels of ferrous ions, and the expression of ferroptosis-related genes in A549 and H1299 lung cancer cell lines treated with or without metformin.ResultsThe results showed that metformin treatment increased the levels of MDA, ROS and iron ions, while decreased the levels of GSH, T-SOD and CAT. Meanwhile, metformin treatment reduced the protein expression levels of Gpx4 and SLC7A11, Nrf2 and HO-1, while the addition of ferroptosis inhibitor ferrostatin-1 reversed the reduction.ConclusionsThese results demonstrated that metformin exerts anti-tumor effects by inducing ferroptosis through the Nrf2/HO-1 signaling pathway in lung cancer cells, providing a theoretical basis for drug therapy of lung cancer patients.

SUMOylation of the ubiquitin ligase component KEAP1 at K39 upregulates NRF2 and its target function in lung cancer cell proliferation

Nuclear Factor Erythroid 2-Related Factor 2 (NRF2) is important for the expression of genes associated with oxidative stress. The levels of NRF2 are controlled by Kelch-like ECH-associated protein 1 (KEAP1)-dependent degradation. Although oxidative stress is known to suppress KEAP1 activity to stabilize the levels of NRF2, the mechanism for this control is unclear. Here, we identify that KEAP1 is modified by SUMO1 at the lysine residue position 39 (K39). Arginine replacement of this lysine (K39R) in KEAP1 did not affect its stability, subcellular localization, or dimerization but promoted the formation of the Cullin 3 ubiquitin ligase and increased NRF2 ubiquitination. This was accompanied by decreased NRF2 expression. Gene reporter assays showed that the transcription of antioxidant response elements was heightened in KEAP1-WT cells compared to cells expressing the KEAP1-K39R SUMO1 substrate mutant. Consistent with this, chromatin immunoprecipitation assays revealed higher NRF2 binding to the promoter regions of antioxidant genes in cells expressing the KEAP1-WT compared to the KEAP1-K39R mutant protein in H1299 lung cancer cell. The significance of this suppression of KEAP1 activity by its SUMOylation was tested in a subcutaneous tumor model of H1299 lung cancer cell lines that differentially expressed the WT and K39R KEAP1 constructs. This model showed that mutating the SUMOylation site on KEAP1 altered the production of reactive oxygen species and suppressed tumor growth. Taken together, our study recognizes that NRF2-dependent redox control is regulated by the SUMOylation of KEAP1. These findings identify a potential new therapeutic option to counteract oxidative stress.

A novel quinoline derivative, DFIQ, sensitizes NSCLC cells to ferroptosis by promoting oxidative stress accompanied by autophagic dysfunction and mitochondrial damage

BackgroundThe development of nonapoptotic programmed cell death inducers as anticancer agents has emerged as a cancer therapy field. Ferroptosis, ferrous ion-driven programmed cell death that is induced by redox imbalance and dysfunctional reactive oxygen species (ROS) clearance, is triggered during sorafenib and PD-1/PD-L1 immunotherapy. DFIQ, a quinoline derivative, promotes apoptosis by disrupting autophagic flux and promoting ROS accumulation. Our pilot experiments suggest that DFIQ participates in ferroptosis sensitization. Thus, in this study, we aimed to reveal the mechanisms of DFIQ in ferroptosis sensitization and evaluate the clinical potential of DFIQ.MethodsWe treated the non-small cell lung cancer (NSCLC) cell lines H1299, A549, and H460 with the ferroptosis inducer (FI) DFIQ and analyzed viability, protein expression, ROS generation, and fluorescence staining at different time points. Colocalization analysis was performed with ImageJ.ResultsDFIQ sensitized cells to FIs such as erastin and RSL3, resulting in a decrease in IC50 of at least 0.5-fold. Measurement of ROS accumulation to explore the underlying mechanism indicated that DFIQ and FIs treatment promoted ROS accumulation and SOD1/SOD2 switching. Mitochondria, known ROS sources, produced high ROS levels during DFIQ/FI treatment. RSL3 treatment promoted mitochondrial damage and mitophagy, an autophagy-associated mitochondrial recycling system, and cotreatment with DFIQ induced accumulation of mitochondrial proteins, which indicated disruption of mitophagic flux. Thus, autophagic flux was measured in cells cotreated with DFIQ. DFIQ treatment was found to disrupt autophagic flux, leading to accumulation of damaged mitochondria and eventually inducing ferroptosis. Furthermore, the influence of DFIQ on the effects of clinical FIs, such as sorafenib, was evaluated, and DFIQ was discovered to sensitize NSCLC cells to sorafenib and promote ferroptosis.ConclusionsThis study indicates that DFIQ not only promotes NSCLC apoptosis but also sensitizes cells to ferroptosis by disrupting autophagic flux, leading to accumulation of dysfunctional mitochondria and thus to ferroptosis. Ferroptosis is a novel therapeutic target in cancer therapy. DFIQ shows the potential to enhance the effects of FIs in NSCLC and act as a potential therapeutic adjuvant in ferroptosis-mediated therapy.

Gastrodin destabilizes survivin and overcomes pemetrexed resistance

Survivin is a bifunctional protein that plays crucial roles in tumorigenesis. In the present study, we discovered that the natural product gastrodin suppressed the cell viability and colony formation of non-small cell lung cancer (NSCLC) cell lines A549, HCC827, and H460 in a dose-dependent manner. In addition, gastrodin enhanced the protein levels of cleaved-caspase 3 by activating the endogenous mitochondrial apoptosis pathway. Gastrodin inhibits protein kinase B (Akt)/WEE1/cyclin-dependent kinase 1 (CDK1) signaling to downregulate survivin Thr34 phosphorylation. Survivin Thr34 dephosphorylation caused by gastrodin interfered with the binding of ubiquitin-specific protease 19 (USP19), which eventually destabilized survivin. We revealed that the growth of NSCLC xenograft tumors was markedly suppressed by gastrodin in vivo. Furthermore, gastrodin overcomes pemetrexed resistance in vivo or in vitro. Our results suggest that gastrodin is a potential antitumor agent by reducing survivin in NSCLC.