Sensitivity Of Lung Cancer Cells Research Articles

Studies on the thermal sensitivity of lung cancer cells exposed to an alternating magnetic field and magnesium-doped maghemite nanoparticles

BackgroundMagnetic fluid hyperthermia (MFH) represents a promising therapeutic strategy in cancer utilizing the heating capabilities of magnetic nanoparticles when exposed to an alternating magnetic field (AMF). Because the efficacy and safety of MFH treatments depends on numerous intrinsic and extrinsic factors, therefore, the proper MFH setups should focus on thermal energy dosed into the cancer cells.MethodsIn this study, we performed MFH experiments using human lung cancer A549 cells (in vitro) and NUDE Balb/c mice bearing human lung (A549) cancer (in vivo). In these two experimental models, the heat was induced by magnesium-doped iron(III) oxide nanoparticles coated with mPEG-silane (Mg0.1-γ-Fe2O3(mPEG-silane)0.5) when exposed to an AMF.ResultsWe observed that the lung cancer cells treated with Mg0.1-γ-Fe2O3(mPEG-silane)0.5 (0.25 mg·mL−1) and magnetized for 30 min at 14.4 kA·m−1 yielded a satisfactory outcome in reducing the cell viability up to ca. 21% (in vitro). The activation energy calculated for this field strength was estimated for 349 kJ·mol−1. Both volumetric measurements and tumor mass assessments confirmed by magnetic resonance imaging (MRI) showed a superior thermal effect in mice bearing human lung cancer injected intratumorally with Mg0.1-γ-Fe2O3(mPEG-silane)0.5 nanoparticles (3 mg·mL−1) and subjected to an AMF (18.3 kA·m−1) for 30 min four times at weekly intervals. Research demonstrated that mice undergoing MFH exhibited a marked suppression of tumor growth (V = 169 ± 94 mm3; p < 0.05) in comparison to the control group of untreated mice. The CEM43 (cumulative number of equivalent minutes at 43 °C) value for these treatments were estimated for ca. 9.6 min with the specific absorption rate (SAR) level ranging from 100 to 150 W·g−1.ConclusionsThe as-obtained results, both cytotoxic and those related to energy calculations and SAR, may contribute to the advancement of thermal therapies, concurrently indicating that the proposed magnetic fluid hyperthermia holds a great potential for further testing in the context of medical applications.Graphical

Chemosensitizing effect of pentoxifylline in sensitive and multidrug-resistant non-small cell lung cancer cells.

Aim: Multidrug resistance (MDR) is frequent in non-small cell lung cancer (NSCLC) patients, which can be due to its fibrotic stroma. This work explores the combination of pentoxifylline, an anti-fibrotic and chitinase 3-like-1 (CHI3L1) inhibitor drug, with conventional chemotherapy to improve NSCLC treatment. Methods: The effect of pentoxifylline in the expression levels of P-glycoprotein (P-gp), CHI3L1 and its main downstream proteins, as well as on cell death, cell cycle profile, and P-gp activity was studied in two pairs of sensitive and MDR counterpart NSCLC cell lines (NCI-H460/NCI-H460/R and A549/A549-CDR2). Association studies between CHI3L1 gene expression and NSCLC patients' survival were performed using The Cancer Genome Atlas (TCGA) analysis. The sensitizing effect of pentoxifylline to different drug regimens was evaluated in both sensitive and MDR NSCLC cell lines. The cytotoxicity of the drug combinations was assessed in MCF10A non-tumorigenic cells. Results: Pentoxifylline slightly decreased the expression levels of CHI3L1, β-catenin and signal transducer and activator of transcription 3 (STAT3), and caused a significant increase in the G1 phase of the cell cycle in both pairs of NSCLC cell lines. A significant increase in the % of cell death was observed in the sensitive NCI-H460 cell line. TCGA analysis revealed that high levels of CHI3L1 are associated with low overall survival (OS) in NSCLC patients treated with vinorelbine. Moreover, pentoxifylline sensitized both pairs of sensitive and MDR NSCLC cell lines to the different drug regimens, without causing significant toxicity to non-tumorigenic cells. Conclusion: This study suggests the possibility of combining pentoxifylline with chemotherapy to increase NSCLC therapeutic response, even in cases of MDR.

Ophiobolin A Covalently Targets Mitochondrial Complex IV Leading to Metabolic Collapse in Cancer Cells.

Ophiobolin A (OPA) is a sesterterpenoid fungal natural product with broad anticancer activity. While OPA possesses multiple electrophilic moieties that can covalently react with nucleophilic amino acids on proteins, the proteome-wide targets and mechanism of OPA remain poorly understood in many contexts. In this study, we used covalent chemoproteomic platforms to map the proteome-wide reactivity of the OPA in a highly sensitive lung cancer cell line. Among several proteins that OPA engaged, we focused on two targets: lysine-72 of cytochrome c oxidase subunit 5A (COX5A) and cysteine-53 of mitochondrial hypoxia induced gene 1 domain family member 2A (HIGD2A). These two subunit proteins are part of complex IV (cytochrome C oxidase) within the electron transport chain and contributed significantly to the antiproliferative activity of OPA. OPA activated mitochondrial respiration in a COX5A- and HIGD2A-dependent manner, leading to an initial spike in mitochondrial ATP and heightened mitochondrial oxidative stress. OPA compromised mitochondrial membrane potential, ultimately leading to ATP depletion. We have used chemoproteomic strategies to discover a unique anticancer mechanism of OPA through activation of complex IV leading to compromised mitochondrial energetics and rapid cell death.

KiSS-1 Modulation by Epigenetic Agents Improves the Cisplatin Sensitivity of Lung Cancer Cells.

Epigenetic alterations my play a role in the aggressive behavior of Non-Small Cell Lung Cancer (NSCLC). Treatment with the histone deacetylase inhibitor suberoylanilide hydroxamic acid (SAHA, vorinostat) has been reported to interfere with the proliferative and invasive potential of NSCLC cells. In addition, the DNA methyltransferase inhibitor azacytidine (AZA, vidaza) can modulate the levels of the metastasis suppressor KiSS-1. Thus, since cisplatin is still clinically available for NSCLC therapy, the aim of this study was to evaluate drug combinations between cisplatin and SAHA as well as AZA using cisplatin-sensitive H460 and -resistant H460/Pt NSCLC cells in relation to KiSS-1 modulation. An analysis of drug interaction according to the Combination-Index values indicated a more marked synergistic effect when the exposure to SAHA or AZA preceded cisplatin treatment with respect to a simultaneous schedule. A modulation of proteins involved in apoptosis (p53, Bax) was found in both sensitive and resistant cells, and compared to the treatment with epigenetic agents alone, the combination of cisplatin and SAHA or AZA increased apoptosis induction. The epigenetic treatments, both as single agents and in combination, increased the release of KiSS-1. Finally, the exposure of cisplatin-sensitive and -resistant cells to the kisspeptin KP10 enhanced cisplatin induced cell death. The efficacy of the combination of SAHA and cisplatin was tested in vivo after subcutaneous inoculum of parental and resistant cells in immunodeficient mice. A significant tumor volume inhibition was found when mice bearing advanced tumors were treated with the combination of SAHA and cisplatin according to the best schedule identified in cellular studies. These results, together with the available literature, support that epigenetic drugs are amenable for the combination treatment of NSCLC, including patients bearing cisplatin-resistant tumors.

HMGN1 loss sensitizes lung cancer cells to chemotherapy

The high mobility group nucleosome binding (HMGN) family, constitutes a large family of non-histone protein family known to bind the acidic patch of the nucleosomes with various key cellular functions. Several studies have highlighted the pivotal roles of HMGNs in the pathogenic process of various cancer types. However, the roles of HMGN family in lung adenocarcinoma (LUAD) have not been fully elucidated. Herein, integrative analyses of multiple-omics data revealed that HMGNs frequently exhibit dysregulation in LUAD. Subsequent analysis of the clinical relevance of HMGN1 demonstrated its association with poor prognosis in LUAD and its potential as a diagnostic marker to differentiate LUAD from healthy controls. Additionally, functional enrichment analysis suggested that HMGN1 was mainly involved in DNA repair. To corroborate these findings, cellular experiments were conducted, confirming HMGN1’s crucial involvement in homologous recombination repair and its potential to enhance the sensitivity of LUAD cells to standard chemotherapeutic drugs. This study proposes HMGN1 as a novel prognostic biomarker and a promising target for chemotherapy in lung adenocarcinoma.

Rolapitant treats lung cancer by targeting deubiquitinase OTUD3

BackgroundLung cancer is cancer with the highest morbidity and mortality in the world and poses a serious threat to human health. Therefore, discovering new treatments is urgently needed to improve lung cancer prognosis. Small molecule inhibitors targeting the ubiquitin-proteasome system have achieved great success, in which deubiquitinase inhibitors have broad clinical applications. The deubiquitylase OTUD3 was reported to promote lung tumorigenesis by stabilizing oncoprotein GRP78, implying that inhibition of OTUD3 may be a therapeutic strategy for lung cancer.ResultsIn this study, we identified a small molecule inhibitor of OTUD3, Rolapitant, by computer-aided virtual screening and biological experimental verification from FDA-approved drugs library. Rolapitant inhibited the proliferation of lung cancer cells by inhibiting deubiquitinating activity of OTUD3. Quantitative proteomic profiling indicated that Rolapitant significantly upregulated the expression of death receptor 5 (DR5). Rolapitant also promoted lung cancer cell apoptosis through upregulating cell surface expression of DR5 and enhanced TRAIL-induced apoptosis. Mechanistically, Rolapitant directly targeted the OTUD3-GRP78 axis to trigger endoplasmic reticulum (ER) stress-C/EBP homologous protein (CHOP)-DR5 signaling, sensitizing lung cancer cells to TRAIL-induced apoptosis. In the vivo assays, Rolapitant suppressed the growth of lung cancer xenografts in immunocompromised mice at suitable dosages without apparent toxicity.ConclusionIn summary, the present study identifies Rolapitant as a novel inhibitor of deubiquitinase OTUD3 and establishes that the OTUD3-GRP78 axis is a potential therapeutic target for lung cancer.

Molecular classification reveals the sensitivity of lung adenocarcinoma to radiotherapy and immunotherapy: multi-omics clustering based on similarity network fusion

BackgroundDue to individual differences in tumors and immune systems, the response rate to immunotherapy is low in lung adenocarcinoma (LUAD) patients. Combinations with other therapeutic strategies improve the efficacy of immunotherapy in LUAD patients. Although radioimmunotherapy has been demonstrated to effectively suppress tumors, the underlying mechanisms still need to be investigated.MethodsTotal RNA from LUAD cells was sequenced before and after radiotherapy to identify differentially expressed radiation-associated genes. The similarity network fusion (SNF) algorithm was applied for molecular classification based on radiation-related genes, immune-related genes, methylation data, and somatic mutation data. The changes in gene expression, prognosis, immune cell infiltration, radiosensitivity, chemosensitivity, and sensitivity to immunotherapy were assessed for each subtype.ResultsWe used the SNF algorithm and multi-omics data to divide TCGA-LUAD patients into three subtypes. Patients with the CS3 subtype had the best prognosis, while those with the CS1 and CS2 subtypes had poorer prognoses. Among the strains tested, CS2 exhibited the most elevated immune cell infiltration and expression of immune checkpoint genes, while CS1 exhibited the least. Patients in the CS2 subgroup were more likely to respond to PD-1 immunotherapy. The CS2 patients were most sensitive to docetaxel and cisplatin, while the CS1 patients were most sensitive to paclitaxel. Experimental validation of signature genes in the CS2 subtype showed that inhibiting the expression of RHCG and TRPA1 could enhance the sensitivity of lung cancer cells to radiation.ConclusionsIn summary, this study identified a risk classifier based on multi-omics data that can guide treatment selection for LUAD patients.

β-Sitosterol attenuates anlotinib resistance in non-small cell lung cancer cells by inhibiting miR-181a-3p/SHQ1 signaling.

Anlotinib is used for the treatment of advanced non-small cell lung cancer; however, the emergence of drug resistance limits its clinical application. β-sitosterol may also be used to treat lung cancer, but there have been no studies evaluating β-sitosterol against anlotinib-resistant lung cancer. The purpose of this study was to determine the mechanism by which β-sitosterol enhances the sensitivity of lung cancer cells to anlotinib. A549 cells were treated with different concentrations of anlotinib to generate anlotinib-resistant cells (A549/anlotinib cells). miR-181a-3p mimics were transfected into A549/anlotinib cells. A549 and A549/anlotinib cells were treated with β-sitosterol at various concentrations. The Cell Counting Kit-8 (CCK-8) assay was used to measure cell proliferation. Apoptosis was assessed by flow cytometry. Real-time quantitative PCR was used to measure the expression of miR-181a-3p. The interaction of miR-181a-3p with the H/ACA ribonucleoprotein assembly factor (SHQ1) was predicted using the miRDB and TargetScan Human databases and verified with a luciferase reporter assay. The expression of SHQ1, activating transcription factor 6 (ATF6), and glucose-regulated protein 78 (GRP78) were measured by western blot analysis. β-Sitosterol effectively suppressed A549/anlotinib cell proliferation and promoted apoptosis. SHQ1 is a downstream target of miR-181a-3p. The expression of miR-181a-3p was inhibited; however, SHQ1 expression was increased by β-sitosterol treatment of A549/anlotinib cells. The inhibition of SHQ1, ATF6, and GRP78 protein expression by β-sitosterol in A549/anlotinib cells was rescued by increased miR-181a-3p. β-Sitosterol markedly promotes anlotinib-resistant A549 cell apoptosis and inhibits cell proliferation by activating SHQ1/UPR signaling through miR-181a-3p inhibition.

SIRT1 ISGylation accelerates tumor progression by unleashing SIRT1 from the inactive state to promote its deacetylase activity

ISG15 is an interferon-stimulated ubiquitin-like protein (UBL) with multifaceted roles as a posttranslational modifier in ISG15 conjugation (ISGylation). However, the mechanistic consequences of ISGylation in cancer have not been fully elucidated, largely due to a lack of knowledge on the ISG15 target repertoire. Here, we identified SIRT1, a nicotinamide adenine dinucleotide (NAD+)-dependent protein deacetylase, as a new target for ISGylation. SIRT1 ISGylation impairs the association of SIRT1 with its negative regulator, deleted in breast cancer 1 (DBC1), which unleashes SIRT1 from its inactive state and leads to an increase in its deacetylase activity. Importantly, SIRT1 ISGylation promoted lung cancer progression and limited lung cancer cell sensitivity to DNA damage-based therapeutics in vivo and in vitro models. The levels of ISG15 mRNA and protein were significantly higher in lung cancer tissues than in adjacent normal tissues. Accordingly, elevated expression of SIRT1 and ISG15 was associated with poor prognosis in lung cancer patients, a finding that could be translated for lung cancer patient stratification and disease outcome evaluation. Taken together, our findings provide a mechanistic understanding of the regulatory effect of SIRT1 ISGylation on tumor progression and therapeutic efficacy in lung cancer.

Ganoderic acid A suppresses autophagy by regulating the circFLNA/miR-486-3p/CYP1A1/XRCC1 axis to strengthen the sensitivity of lung cancer cells to cisplatin.

Reportedly, ganoderic acid A (GA-A) increases the sensitivity of hepatocellular carcinoma cells to cisplatin (DDP) chemotherapy. Therefore, this study aims to fathom the influence of GA-A on lung cancer cells. After the construction of A549/DDP cells through exposure to DDP, the effects of GA-A on A549 and A549/DDP cells were revealed by cellular functional assays, western blot and quantitative reverse transcription PCR (qRT-PCR). The DDP-resistant lung cancer tumor was established in vivo, followed by further validation of the mechanism of GA-A. GA-A suppressed the viability, migration, and invasion while downregulating Beclin and autophagy marker LC3II/LC3I levels and upregulating P62 levels in A549 and A549/DDP cells. These effects were reversed by circFLNA overexpression. Also, GA-A reinforced the sensitivity of A549/DDP cells to DDP, elevated the apoptosis and regulated the circFLNA/miR-486-3p/cytochrome P450 family 1 subfamily A member 1 (CYP1A1)/X-ray repair cross-complementing 1 (XRCC1) axis. The reversal effects of circFLNA overexpression on GA-A-induced viability and apoptosis of A549/DDP cells could all be counteracted in the presence of 3MA. GA-A inhibited lung cancer tumor growth and blocked autophagy. GA-A suppresses autophagy by regulating the circFLNA/miR-486-3p/CYP1A1/XRCC1 axis to strengthen the sensitivity of lung cancer cells to DDP.

Phytohemagglutinin fromPhaseolusvulgarisenhancesthelungcancercell chemotherapy sensitivitybychangingcellmembrane permeability.

Chemotherapy is still a prevalent strategy for clinical lung cancer treatment. However, the inevitable emerged drug resistance has become a great hurdle to therapeutic effect. Studies have demonstrated that the primary cause of drug resistance is a decrease in the chemotherapeutic medicine concentration. Several lectins have been confirmed to be effective as chemotherapy adjuvants, enhancing the anti-tumor effects of chemotherapy drugs. Here, we combined phytohemagglutinin (PHA), which has been reported possess anti-tumor effects, with chemotherapy drugs Cisplatin (DDP) and Adriamycin (ADM) on lung cancer cells to detect the sensitivities of PHA as a chemotherapy adjuvant. Our results demonstrated that the PHA significantly enhanced the sensitivity of lung cancer cells to DDP and ADM, and Western blot showed that PHA combined with DDP or ADM enhance cytotoxic effects by inhibiting autophagy and promoting apoptosis. More importantly, we found PHA enhanced the chemotherapeutic drugs cytotoxicity by changing the cell membrane to increase the intracellular chemotherapeutic drugs concentration. Besides, the combination of PHA and ADM increased the ADM concentration in the multidrug-resistant strain A549-R cells and achieved the drug sensitization effect. Our results suggest that PHA combined with chemotherapy can be applied in the treatment of lung cancer cells and lung cancer multidrug-resistant strains, and provide a novel strategy for clinical tumor chemotherapy and a new idea to solve the problem of drug resistance in clinical lung cancer.

Blocking lncRNA HCG18 re-sensitizes Taxol resistant lung cancer cells to Taxol through modulating the miR-34a-5p/HDAC1 axis

Lung cancer is one of the most frequently diagnosed cancers worldwide, associated with a poor survival rate. Taxol (Paclitaxel) is commonly used as a chemotherapeutic treatment for advanced lung cancers. While Taxol has improved clinical outcomes for lung cancer patients, a significant number of them develop resistance to Taxol, resulting in treatment failure. The role of the long noncoding RNA HCG18 in lung cancer and Taxol resistance has not yet been fully understood. To investigate this, we examined the expression of HCG18 and miR-34a-5p in lung tumors and normal lung tissues using qRT-PCR. We also assessed Taxol resistance through cell viability and apoptosis assays. Through the starBase online service, we analyzed the interactions between lncRNA and mRNA as well as miRNA and mRNA. We further validated the association between lncRNA and miRNA through luciferase and RNA pull-down assays. Our findings demonstrated that HCG18 was significantly upregulated in lung cancer tissues compared to normal lung tissues. Silencing HCG18 increased the sensitivity of lung cancer cells to Taxol. Additionally, our study established a Taxol-resistant cell line and observed a substantial upregulation of HCG18 in Taxol-resistant lung cancer cells. Bioinformatic analysis predicted that HCG18 could bind to miR-34a-5p, forming a competing endogenous RNA network, which was confirmed through luciferase assay. We found that miR-34a-5p was downregulated in lung cancer tissues and negatively correlated with Taxol resistance, as it directly bound to the 3’UTR region of HDAC1. Further results showed that inhibition of HCG18 significantly increased miR-34a-5p expression and sensitized lung cancer cells to Taxol. This sensitization could be reversed by inhibiting miR-34a-5p. Finally, we demonstrated in a xenograft mouse model that inhibition of HCG18 sensitized Taxol-resistant lung cancer cells to Taxol treatment by modulating the miR-34a-5p-HDAC1 axis. In conclusion, our in vitro and in vivo results uncover a novel molecular mechanism by which HCG18 promotes Taxol resistance through modulation of the miR-34a-5p/HDAC1 axis. These findings contribute to the diagnosis and treatment of chemo-resistant lung cancer.

Downregulation of TRIB3 enhances the sensitivity of lung cancer cells to amino acid deprivation by suppressing AKT activation.

Tribbles pseudokinase 3 (TRIB3), a member of the mammalian Tribbles family, is implicated in multiple biological processes. This study aimed to investigate the biological functions of TRIB3 in lung cancer and its effect on amino acid-deprived lung cancer cells. TRIB3 mRNA expression was elevated in lung cancer tissues and cell lines compared to normal lung tissues and cells. TRIB3 knockdown markedly reduced the viability and proliferation of H1299 lung cancer cells. Deprivation of amino acids, particularly arginine, glutamine, lysine, or methionine, strongly increased TRIB3 expression via ATF4 activation in H1299 lung cancer cells. Knockdown of TRIB3 led to transcriptional downregulation of ATF4 and reduced AKT activation induced by amino acid deprivation, ultimately increasing the sensitivity of H1299 lung cancer cells to amino acid deprivation. Additionally, TRIB3 knockdown enhanced the sensitivity of H1299 cells to V-9302, a competitive antagonist of transmembrane glutamine flux. These results suggest that TRIB3 is a pro-survival regulator of cell viability in amino acid-deficient tumor microenvironments and a promising therapeutic target for lung cancer treatment.

LncRNA FEZF1-AS1 facilitates cisplatin resistance in non-small cell lung cancer through modulating the miR-32-5p-glutaminase axis.

Non-small cell lung cancer (NSCLC) is one of the prevalent malignancies. Cisplatin (CDDP) is a conventional chemotherapeutic agent against NSCLC. However, inherent and acquired chemoresistance limited the effectiveness of cisplatin in treatment of NSCLC. This study aimed to investigate the roles and underlying mechanisms of lncRNA-FEZF1-AS1 in mediating cisplatin sensitivity in NSCLC. We found that FEZF1-AS1 levels were significantly higher in lung cancer patients and cell lines. Blocking FEZF1-AS1 sensitized lung cancer cells to cisplatin. Additionally, both glutamine metabolism and FEZF1-AS1 were significantly elevated in cisplatin resistant NSCLC cell lines, A549/CDDP R and SK-MES-1 CDDP/R. Analysis using bioinformatics, RNA pull-down assay and luciferase assay demonstrated that FEZF1-AS1 sponged miR-32-5p, which acted as a tumor suppressor in NSCLC. Glutaminase (GLS), a key enzyme in the glutamine metabolism, was predicted and validated as the direct target of miR-32-5p in NSCLC cells. Inhibiting glutamine metabolism or reducing glutamine supply effectively resensitized cisplatin-resistant cells. Furthermore, restoring miR-32-5p in FEZF1-AS1-overexpressing cisplatin resistant cells successfully overcame FEZF1-AS1-mediated cisplatin resistance by targeting GLS. These findings were further supported by in vivo xenograft mice experiments. This study uncovered the roles and molecular mechanisms of lncRNA FEZF1-AS1 in mediating cisplatin resistance in NSCLC, specifically through modulating the miR-32-5p-GLS axis, providing support for the development of new therapeutic approaches against chemoresistant lung cancer.

MiR-204 suppresses cancer stemness and enhances osimertinib sensitivity in non-small cell lung cancer by targeting CD44

Osimertinib is an effective treatment option for patients with advanced non-small cell lung cancer (NSCLC) with EGFR activation or T790M resistance mutations; however, acquired resistance to osimertinib can still develop. This study explored novel miRNA-mRNA regulatory mechanisms that contribute to osimertinib resistance in lung cancer. We found that miR-204 expression in osimertinib-resistant lung cancer cells was markedly reduced compared to that in osimertinib-sensitive parental cells. miR-204 expression levels in cancer cells isolated from treatment-naive pleural effusions were significantly higher than those in cells with acquired resistance to osimertinib. miR-204 enhanced the sensitivity of lung cancer cells to osimertinib and suppressed spheroid formation, migration, and invasion of lung cancer cells. Increased miR-204 expression in osimertinib-resistant cells reversed resistance to osimertinib and enhanced osimertinib-induced apoptosis by upregulating BIM expression levels and activating caspases. Restoration of CD44 (the direct downstream target gene of miR-204) expression reversed the effects of miR-204 on osimertinib sensitivity, recovered cancer stem cell and mesenchymal markers, and suppressed E-cadherin expression. The study demonstrates that miR-204 reduced cancer stemness and epithelial-to-mesenchymal transition, thus overcoming osimertinib resistance in lung cancer by inhibiting the CD44 signaling pathway.

An Antidepressant Drug Increased TRAIL Receptor-2 Expression and Sensitized Lung Cancer Cells to TRAIL-induced Apoptosis.

TRAIL has emerged as a promising therapeutic target due to its ability to selectively induce apoptosis in cancer cells while sparing normal cells. Autophagy, a highly regulated cellular recycling mechanism, is known to play a cell survival role by providing a required environment for the cell. Recent studies suggest that autophagy plays a significant role in increasing TRAIL resistance in certain cancer cells. Thus, regulating autophagy in TRAIL-mediated cancer therapy is crucial for its role in cancer treatment. Our study explored whether the antidepressant drug desipramine could enhance the ability of TRAIL to kill cancer cells by inhibiting autophagy. The effect of desipramine on TRAIL sensitivity was examined in various lung cancer cell lines. Cell viability was measured by morphological analysis, trypan blue exclusion, and crystal violet staining. Flow cytometry analysis was carried out to measure apoptosis with annexin V-PI stained cells. Western blotting, rtPCR, and immunocytochemistry were carried out to measure autophagy and death receptor expression. TEM was carried out to detect autophagy inhibition. Desipramine treatment increased the TRAIL sensitivity in all lung cancer cell lines. Mechanistically, desipramine treatment induced death receptor expression to increase TRAIL sensitivity. This effect was confirmed when the genetic blockade of DR5 reduced the effect of desipramine in enhanced TRAIL-mediated cell death. Further investigation revealed that desipramine treatment increased the LC3 and p62 levels, indicating the inhibition of lysosomal degradation of autophagy. Notably, TRAIL, in combination with either desipramine or the autophagy inhibitor chloroquine, exhibited enhanced cytotoxicity compared to TRAIL treatment alone. Our findings revealed the potential of desipramine to induce TRAIL-mediated cell death by autophagy impairment. This discovery suggests its therapeutic potential for inducing TRAIL-mediated cell death by increasing the expression of death receptors, which is caused by impairing autophagy.

Phillyrin sensitizes lung cancer cells to ferroptosis through inhibiting FTH1/SLC7A11 axis.

Ferroptosis is a newly found form of non-apoptotic regulated cell death that is essential for cancer progression. Phillyrin (PHN), an effective lignan glycoside of Forsythia suspensa, has been explored as a potential anticancer agent in some cancer types. However, it is unclear whether and how PHN could promote the death of non-small cell lung cancer (NSCLC) cells by inducing ferroptosis. Our study showed for the first time that PHN induced cell death and attenuated cell proliferation in NSCLC cells in vitro and in vivo. Functional assays showed that ferroptosis was the predominant form that contributed to PHN-induced cell death of NSCLC cells. Mechanistically, NSCLC cells exposed to PHN had a decreased ferritin heavy chain 1 (FTH1) and SLC7A11 protein expression. Exogenetic overexpression of FTH1 substantially abrogated the tumor-inhibiting effects of PHN and further upregulated the expression of SLC7A11 in NSCLC cells. In conclusion, our findings suggest that the natural product PHN exerted its antitumor activity in NSCLC by promoting ferroptosis, and the FTH1/SLC7A11 axis plays an indispensable role in PHN-induced ferroptotic cell death.

Susceptibility of various human cancer cell lines to nanosecond and microsecond range electrochemotherapy: Feasibility of multi-drug cocktails

Electrochemotherapy (ECT) involves combining anticancer drugs with electroporation, which is induced by pulsed electric fields (PEFs), while the effects vary in effectiveness based on the specific parameters of the electrical pulses and susceptibility of the cells to a specific drug. In this work, we utilized conventional microsecond electroporation protocols (0.8 – 1.5 kV/cm × 100 μs × 8, 1 Hz) and the new modality of nanosecond pulses (4 and 8 kV/cm × 500 ns × 100, 1 kHz and 1 MHz), which are compressed into a high frequency burst. Sensitive and resistant lung, breast and ovarian human cancer cell lines were used in the study. In order to overcome drug-resistance, we have investigated the feasibility to use anticancer drug cocktails i.e., bleomycin and cisplatin combinations with metformin, vinorelbine and Dp44mT. The different susceptibility of various human cancer cells lines to electric pulses was determined, the efficacy of ECT was characterized and the type of cell death depending on the combinations of drugs was investigated. The results indicate that synergistic effects of PEFs with drug cocktails may be used to overcome drug-resistance in cancer, while the application of nsPEF provides more flexibility in parametric protocols and modulation of cancer cell death.

Overexpression of SERPINA3 suppresses tumor progression by modulating SPOP/NF‑κB in lung cancer.

The pathogenesis mechanism of lung cancer is very complex, with high incidence and mortality. Serpin family A member 3 (SERPINA3) expression levels were reduced in the sera of patients with lung cancer and may be a candidate diagnostic and prognostic survival biomarker in lung cancer, as previously reported. However, the detailed biological functions of SERPINA3 in the pathogenesis of lung cancer remain unknown. In the present study, it was aimed to explore the effects of SERPINA3 on the occurrence of lung cancer. SERPINA3 expression was assessed using bioinformatics database analysis and experimental detection. Then, the biological effects of SERPINA3 were investigated in a cell culture system and a xenograft model of human lung cancer. The potential regulatory mechanism of SERPINA3 in lung cancer was explored by data‑independent acquisition mass spectrometry (DIA‑MS) detection and further validated by western blotting (WB). The results indicated that SERPINA3 expression levels were significantly downregulated in lung cancer tissues and cell lines. At the cellular level, it was revealed that overexpressed SERPINA3 inhibited cell growth, proliferation, migration and invasion and promoted the apoptosis of lung cancer cells. Moreover, overexpressed SERPINA3 enhanced the sensitivity of lung cancer cells to osimertinib. Invivo, a xenograft model of human lung cancer was established with BALB/c nude mice. After the injection of A549 cells, the tumor growth of the tumor‑bearing mice in the SERPINA3‑overexpressing group increased more slowly, and the tumor volume was smaller than that in the empty‑vector group. Mechanistically, a total of 65 differentially expressed proteins were identified. It was found that the speckle‑type POZ protein (SPOP) was significantly upregulated in SERPINA3‑overexpressing H157 cells using DIA‑MS detection and analysis. WB validation showed that SPOP expression increased, and NF‑kappaB (NF‑κB) p65 was inhibited in cell lines and tumor tissues of mice when SERPINA3 was overexpressed. The present findings suggest that SERPINA3 is involved in the development of lung cancer and has an antineoplastic role in lung cancer.

MEN1 is a regulator of alternative splicing and prevents R-loop-induced genome instability through suppression of RNA polymerase II elongation.

The fidelity of alternative splicing (AS) patterns is essential for growth development and cell fate determination. However, the scope of the molecular switches that regulate AS remains largely unexplored. Here we show that MEN1 is a previously unknown splicing regulatory factor. MEN1 deletion resulted in reprogramming of AS patterns in mouse lung tissue and human lung cancer cells, suggesting that MEN1 has a general function in regulating alternative precursor mRNA splicing. MEN1 altered exon skipping and the abundance of mRNA splicing isoforms of certain genes with suboptimal splice sites. Chromatin immunoprecipitation and chromosome walking assays revealed that MEN1 favored the accumulation of RNA polymerase II (Pol II) in regions encoding variant exons. Our data suggest that MEN1 regulates AS by slowing the Pol II elongation rate and that defects in these processes trigger R-loop formation, DNA damage accumulation and genome instability. Furthermore, we identified 28 MEN1-regulated exon-skipping events in lung cancer cells that were closely correlated with survival in patients with lung adenocarcinoma, and MEN1 deficiency sensitized lung cancer cells to splicing inhibitors. Collectively, these findings led to the identification of a novel biological role for menin in maintaining AS homeostasis and link this role to the regulation of cancer cell behavior.