Blocking NF-κB sensitizes non-small cell lung cancer cells to histone deacetylase inhibitor induced extrinsic apoptosis through generation of reactive oxygen species

Energy metabolism as the hub of advanced non-small cell lung cancer management: a comprehensive view in the framework of predictive, preventive, and personalized medicine

Energy metabolism is a hub of governing all processes at cellular and organismal levels such as, on one hand, reparable vs. irreparable cell damage, cell fate (proliferation, survival, apoptosis, malignant transformation etc.), and, on the other hand, carcinogenesis, tumor development, progression and metastazing versus anti-cancer protection and cure. The orchestrator is the mitochondria who produce, store and invest energy, conduct intracellular and systemically relevant signals decisive for internal and environmental stress adaptation, and coordinate corresponding processes at cellular and organismal levels. Consequently, the quality of mitochondrial health and homeostasis is a reliable target for health risk assessment at the stage of reversible damage to the health followed by cost-effective personalized protection against health-to-disease transition as well as for targeted protection against the disease progression (secondary care of cancer patients against growing primary tumors and metastatic disease). The energy reprogramming of non-small cell lung cancer (NSCLC) attracts particular attention as clinically relevant and instrumental for the paradigm change from reactive medical services to predictive, preventive and personalized medicine (3PM). This article provides a detailed overview towards mechanisms and biological pathways involving metabolic reprogramming (MR) with respect to inhibiting the synthesis of biomolecules and blocking common NSCLC metabolic pathways as anti-NSCLC therapeutic strategies. For instance, mitophagy recycles macromolecules to yield mitochondrial substrates for energy homeostasis and nucleotide synthesis. Histone modification and DNA methylation can predict the onset of diseases, and plasma C7 analysis is an efficient medical service potentially resulting in an optimized healthcare economy in corresponding areas. The MEMP scoring provides the guidance for immunotherapy, prognostic assessment, and anti-cancer drug development. Metabolite sensing mechanisms of nutrients and their derivatives are potential MR-related therapy in NSCLC. Moreover, miR-495-3p reprogramming of sphingolipid rheostat by targeting Sphk1, 22/FOXM1 axis regulation, and A2 receptor antagonist are highly promising therapy strategies. TFEB as a biomarker in predicting immune checkpoint blockade and redox-related lncRNA prognostic signature (redox-LPS) are considered reliable predictive approaches. Finally, exemplified in this article metabolic phenotyping is instrumental for innovative population screening, health risk assessment, predictive multi-level diagnostics, targeted prevention, and treatment algorithms tailored to personalized patient profiles-all are essential pillars in the paradigm change from reactive medical services to 3PM approach in overall management of lung cancers. This article highlights the 3PM relevant innovation focused on energy metabolism as the hub to advance NSCLC management benefiting vulnerable subpopulations, affected patients, and healthcare at large.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13167-024-00357-5.

Up-regulation of TNF-alpha/NFkB/SIRT1 axis drives aggressiveness and cancer stem cells accumulation in chemoresistant oral squamous cell carcinoma

Tumor resistance remains an obstacle to successfully treating oral squamous cell carcinoma (OSCC). Cisplatin is widely used as a cytotoxic drug to treat solid tumors, including advanced OSCC, but with low efficacy due to chemoresistance. Therefore, identifying the pathways that contribute to chemoresistance may show new possibilities for improving the treatment. This work explored the role of the tumor necrosis factor-alpha (TNF-alpha)/NFkB signaling in driving the cisplatin resistance of OSCC and its potential as a pharmacological target to overcome chemoresistance. Differential accessibility analysis demonstrated the enrichment of opened chromatin regions in members of the TNF-alpha/NFkB signaling pathway, and RNA-Seq confirmed the upregulation of TNF-alpha/NFkB signaling in cisplatin-resistant cell lines. NFkB was accumulated in cisplatin-resistant cell lines and in cancer stem cells (CSC), and the administration of TNF-alpha increased the CSC, suggesting that TNF-alpha/NFkB signaling is involved in the accumulation of CSC. TNF-alpha stimulation also increased the histone deacetylases HDAC1 and SIRT1. Cisplatin-resistant cell lines were sensitive to the pharmacological inhibition of NFkB, and low doses of the NFkB inhibitors, CBL0137, and emetine, efficiently reduced the CSC and the levels of SIRT1, increasing histone acetylation. The NFkB inhibitors decreased stemness potential, clonogenicity, migration, and invasion of cisplatin-resistant cell lines. The administration of the emetine significantly reduced the tumor growth of cisplatin-resistant xenograft models, decreasing NFkB and SIRT1, increasing histone acetylation, and decreasing CSC. TNF-alpha/NFkB/SIRT1 signaling regulates the epigenetic machinery by modulating histone acetylation, CSC, and aggressiveness of cisplatin-resistant OSCC and the NFkB inhibition is a potential strategy to treat chemoresistant OSCC.

Repurposing of histone deacetylase inhibitors: A promising strategy to combat pulmonary fibrosis promoted by TGF-β signalling in COVID-19 survivors

Coronavirus disease 2019 (COVID-19) has rapidly spread around the world causing global public health emergency. In the last twenty years, we have witnessed several viral epidemics such as severe acute respiratory syndrome coronavirus (SARS-CoV), Influenza A virus subtype H1N1 and most recently Middle East respiratory syndrome coronavirus (MERS-CoV). There were tremendous efforts endeavoured globally by scientists to combat these viral diseases and now for SARS-CoV-2. Several drugs such as chloroquine, arbidol, remdesivir, favipiravir and dexamethasone are adopted for use against COVID-19 and currently clinical studies are underway to test their safety and efficacy for treating COVID-19 patients. As per World Health Organization reports, so far more than 16 million people are affected by COVID-19 with a recovery of close to 10 million and deaths at 600,000 globally.

SARS-CoV-2 infection is reported to cause extensive pulmonary damages in affected people. Given the large number of recoveries, it is important to follow-up the recovered patients for apparent lung function abnormalities. In this review, we discuss our understanding about the development of long-term pulmonary abnormalities such as lung fibrosis observed in patients recovered from coronavirus infections (SARS-CoV and MERS-CoV) and probable epigenetic therapeutic strategy to prevent the development of similar pulmonary abnormalities in SARS-CoV-2 recovered patients. In this regard, we address the use of U.S. Food and Drug Administration (FDA) approved histone deacetylase (HDAC) inhibitors therapy to manage pulmonary fibrosis and their underlying molecular mechanisms in managing the pathologic processes in COVID-19 recovered patients.

Purification, characterization and biological functions of metalloprotein isolated from haemolymph of mud crab Scylla serrata (Forskal, 1775)

In recent years, an enormous number of naturally occurring biological macromolecules has been reported worldwide due to its antibacterial and anticancerous potential. Among them, in this study, the copper containing respiratory protein namely haemocyanin (HC) was isolated from the haemolymph of mud crab Scylla serrata. The isolated metalloprotein HC was purified using Sepharose column by gel filtration chromatography. The purified HC was separated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and molecular weight of the protein was identified as 95 kDa. Fourier transform infrared spectrophotometer (FT-IR) and nuclear magnetic resonance (¹H NMR) spectral data revealed the presence of amino acid constituents. Liquid chromatography tandem mass spectrometry (LC-MS/MS) analysis based mass ion search exposed that the purified protein was HC. HC exhibited an in vitro bacteriostatic effects against the bacterial pathogens and also elevated ROS levels in the treated samples. The half maximal (50%) inhibitory concentration (IC₅₀) of HC was found to be 80 μg/mL against lung cancer cells (A549). Our study collectively addressed the potential antibacterial and anti-cancerous activity of HC. The results obtained from this study suggest that HC can be used for therapeutical application in the near future.

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

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

Fabrication of MgO nanostructures and its efficient photocatalytic, antibacterial and anticancer performance

Magnesium oxide (MgO) nanostructures were prepared using microwave-assisted (M 1) and hydrothermal (M 2) methods and characterized by XRD, SEM and FT-IR. It exhibits cubic structure with an average crystallite size of 20 nm (M 1) and 14 nm (M 2) and the lattice strain (WH plot) is 0.0017 (M 1), 0.0037 (M 2). It's spherical and rods like structures are confirmed through SEM and TEM. The vibrational stretching mode of MgO is 439 (M 1) and 449 cm^-1 (M 2). The optical bandgap is estimated as 5.93 eV (M 1) and 5.85 eV (M 2) through UV-Vis spectra. The fluorescence spectrum shows emission peaks at 414 and 437 (M 1) and 367 and 385 nm (M 2). The photodegradation studies of MgO nanostructures were assessed by monitoring the decolorization of methylene blue and Congo red dyes in aqueous solution under sunlight irradiation. The antibacterial activities of M 1 and M 2 are investigated against the gram-negative (Escherichia coli, Shigella flexneri, Salmonella typhi, Proteus mirabilis, Aeromonas hydrophila and Vibrio cholera) and gram-positive (Bacillus subtilis and Rhodococcus rhodochrous) bacteria. The zone of inhibition of 24 (M 1) and 25 mm (M 2) indicates high antibacterial activity towards the gram negative bacterium A. hydrophila. Confocal laser scanning microscopic (CLSM) analysis was utilized for understanding the variation in antibacterial activity between different orientations of MgO nanostructures. The cytotoxicity assay confirmed that the prepared nanostructures are non - toxic to normal healthy RBC's. In-vitro anticancer efficiency (IC₅₀) of MgO nanostructures against human lung cancer cell line (A549) was investigated.

Induction of reactive oxygen species: an emerging approach for cancer therapy

Reactive oxygen species (ROS), a group of ions and molecules, include hydroxyl radicals (·OH), alkoxyl radicals, superoxide anion (O₂·-), singlet oxygen (¹O₂) and hydrogen peroxide (H₂O₂). Hydroxyl radicals and alkoxyl radicals are extremely and highly reactive species respectively. Endogenous ROS are mainly formed in mitochondrial respiratory chain. Low levels of ROS play important roles in regulating biological functions in mammalian cells. However, excess production of ROS can induce cell death by oxidative damaging effects to intracellular biomacromolecules. Cancer cell death types induced by ROS include apoptotic, autophagic, ferroptotic and necrotic cell death. Since abnormal metabolism in cancer cells, they have higher ROS content compared to normal cells. The higher endogenous ROS levels in cancer cells endow them more susceptible to the ROS-induction treatment. Indeed, some anticancer drugs currently used in clinic, such as molecular targeted drugs and chemotherapeutic agents, effectively kill cancer cells by inducing ROS generation. In addition, photodynamic therapy (PDT) is mainly based on induction of ROS burst to kill cancer cells. The mechanism of cell death induced by radiotherapy using ionizing radiation also refers to ROS production. Moreover, ROS play an important role in tumor immune therapy. Altogether, combining above traditional treatments with ROS-induced agents will be considered as a promising strategy in cancer therapy. In this review, we focus on our current understanding of the anticancer effects of ROS.

Reactive Oxygen Species-Mediated Tumor Microenvironment Transformation: The Mechanism of Radioresistant Gastric Cancer

Radioresistance is one of the primary causes responsible for therapeutic failure and recurrence of cancer. It is well documented that reactive oxygen species (ROS) contribute to the initiation and development of gastric cancer (GC), and the levels of ROS are significantly increased in patients with GC accompanied with abnormal expressions of multiple inflammatory factors. It is also well documented that ROS can activate cancer cells and inflammatory cells, stimulating the release of a variety of inflammatory cytokines, which subsequently mediates the tumor microenvironment (TME) and promotes cancer stem cell (CSC) maintenance as well as renewal and epithelial-mesenchymal transition (EMT), ultimately resulting in radioresistance and recurrence of GC.

COMMD7 activates CXCL10 production by regulating NF-κB and the production of reactive oxygen species

While >80% of the incidence occurs in sub‑Saharan Africa and East Asia, cases of hepatocellular carcinoma (HCC) have been rapidly increasing in Western countries. Despite its global importance, HCC is relatively under‑researched compared with other lethal cancer types, which is possibly due to the high complexity and heterogeneity of HCC. It has been reported previously that COMM domain‑containing protein 7 (COMMD7) is upregulated in HCC and promotes HCC cell proliferation by triggering C‑X‑C motif chemokine 10 (CXCL10) production. However, the value of targeting CXCL10 signal transduction in treating COMMD7‑positive tumors, or the molecular mechanisms underlying COMMD7‑mediated CXCL10 expression, has not been completely addressed. In the present study, it was demonstrated that disruption of the CXCL10/C‑X‑C chemokine receptor type 3 axis reduces COMMD7‑mediated HCC cell proliferation. Furthermore, COMMD7 modulates CXCL10 production by activating nuclear factor (NF)‑κB. Additionally, it was demonstrated that intracellular reactive oxygen species (ROS) are required for NF‑κB activation and CXCL10 production. In conclusion, COMMD7 activates CXCL10 production by regulating NF‑κB and the production of ROS. The present study highlighted the role of COMMD7 in the development of HCC, and provides novel options for anticancer drug design.

Target delivery of doxorubicin tethered with PVP stabilized gold nanoparticles for effective treatment of lung cancer

Development of drug delivery system conjugated with doxorubicin (dox) on the surface of AuNPs with polyvinylpyrrolidone (Dox@PVP-AuNPs), we have demonstrated that human lung cancer cells can significantly overcome by the combination of highly effective cellular entry and responsive intracellular release of doxorubicin from Dox@PVP-AuNPs complex. Previously drug release from doxorubicin-conjugated AuNPs was confirmed by the recovered fluorescence of doxorubicin from quenching due to the nanosurface energy transfer between doxorubicinyl groups and AuNPs. Dox@PVP-AuNPs achieved enhanced inhibition of lung cancer cells growth than free Doxorubicin and PVP-AuNPs. The in vitro cytotoxic effect of PVP-AuNPs, free Dox and Dox@PVP-AuNPs inhibited the proliferation of human lung cancer cells with IC50 concentration. Compared with control cells, PVP-AuNPs and free Dox, Dox@PVP-AuNPs can increases ROS generation, sensitize mitochondrial membrane potential and induces both early and late apoptosis in lung cancer cells. Moreover, Dox@PVP-AuNPs highly upregulates the expression of tumor suppressor genes than free Dox and PVP-AuNPs and induces intrinsic apoptosis in lung cancer cells. From the results, Dox@PVP-AuNPs can be considered as an potential drug delivery system for effective treatment of human lung cancer.

Design, synthesis, and characterization of α, β-unsaturated carboxylic acid, and its urea based derivatives that explores novel epigenetic modulators in human non-small cell lung cancer A549 cell line

Histone deacetylase inhibitors (HDACi) are a small molecule chemotherapeutics that target the chromatin remodeling through the regulation of histone and non-histone proteins. These inhibitors directed against histone deacetylase (HDAC) enzymes have become an important therapeutic tool in oncology; consequently, scientific efforts have fortified the quest for newer and novel HDACi, which forces the design of structurally innovative HDACi. Various urea containing compounds exhibited admirable anticancer activity. On the basis of these observations, we design and synthesize HDAC specific blocker molecules which are specifically besieged towards class I, class II, and class IV HDAC isoforms to enhance the structural assortment for HDACi. Through docking experiments, we identified that the compounds were tightly bound to the isoforms of the HDAC enzymes at their receptor regions. These derivatives potently inhibited the different isoforms, namely, class I, II, and IV of HDACs, by hyperacetylation of lysine residues in A549 cells. The mechanism of apoptosis is evident, regulating tumor suppressor genes and proteins, thereby facilitating the activation of the death receptor pathway by the tumor necrosis factor (TNF) receptor. These derivative facilitated the induction of reactive oxygen species (ROS) generation leading to downregulation of Bcl₂ , and upregulation of Bax expression, thereby dysregulating mitochondrial membrane potential (ΔΨ_m ) to release cytochrome c, and activation of intrinsic pathway. These compounds downregulate the extracellular signal-regulated kinase/mitogen-activated protein kinase (ERK/MAPK) pathway to inhibit cell growth, proliferation, and metastasis through the matrix metalloproteinases (MMPs) MMP2 and MMP9 in A549 cells. These results suggest that our designed urea based derivatives act as epigenetic targeting agents through HDAC inhibition.

Unconventional Approaches to Modulating the Immunogenicity of Tumor Cells

For several years, it has been known that histone deacetylase inhibitors have the potential to alter the immunogenicity of tumor cells exposed to checkpoint inhibitory immunotherapy antibodies. HDAC inhibitors can rapidly reduce expression of PD-L1 and increase expression of MHCA in various tumor types that subsequently facilitate the antitumor actions of checkpoint inhibitors. Recently, we have discovered that drug combinations which cause a rapid and intense autophagosome formation also can modulate the expression of HDAC proteins that control tumor cell immunogenicity via their regulation of PD-L1 and MHCA. These drug combinations, in particular those using the irreversible ERBB1/2/4 inhibitor neratinib, can result in parallel in the internalization of growth factor receptors as well as fellow-traveler proteins such as mutant K-RAS and mutant N-RAS into autophagosomes. The drug-induced autophagosomes contain HDAC proteins/signaling proteins whose expression is subsequently reduced by lysosomal degradation processes. These findings argue that cancer therapies which strongly promote autophagosome formation and autophagic flux may facilitate the subsequent use of additional antitumor modalities using checkpoint inhibitor antibodies.

Combination Therapies Targeting HDAC and IKK in Solid Tumors

The rationale for developing histone deacetylase (HDAC) inhibitors (HDACi) as anticancer agents was based on their ability to induce apoptosis and cell cycle arrest in cancer cells. However, while HDACi have been remarkably effective in the treatment of hematological malignancies, clinical studies with HDACi as single agents in solid cancers have been disappointing. Recent studies have shown that, in addition to inducing apoptosis in cancer cells, class I HDACi induce IκB kinase (IKK)-dependent expression of proinflammatory chemokines, such as interleukin-8 (IL8; CXCL8), resulting in the increased proliferation of tumor cells, and limiting the effectiveness of HDACi in solid tumors. Here, we discuss the mechanisms responsible for HDACi-induced CXCL8 expression, and opportunities for combination therapies targeting HDACs and IKK in solid tumors.

Induction of colon and cervical cancer cell death by cinnamic acid derivatives is mediated through the inhibition of Histone Deacetylases (HDAC)

Recent studies from our group and many others have shown the ability of histone deacetylase (HDAC) inhibitors for retarding the growth of carcinomas of cervix, colon and rectum in vitro. A search for naturally occurring HDAC inhibitors continues due to the adverse effects associated with known HDAC inhibitors like SAHA and TSA. Therefore in the current study, naturally occurring cinnamic acids derivatives were screened for HDAC inhibitory effect using in silico docking method which identified cinnamic acids as potential candidates. Cinnamic acids (CA) are naturally occurring phenolic compounds known to exhibit anticancer properties. However, it is not clearly known whether the anticancer properties of CA derivatives are due to the inhibition of oncogenic HDACs, if so how the efficacy varies among various CA derivatives. Hence, the HDAC inhibitory potential of CA derivatives containing increasing number of hydroxylic groups or methoxy moieties was determined using Discovery Studio software and the most potent CA derivatives tested ex vivo (biochemical assay) as well as in vitro (using cell based assay). Among CA derivatives tested, dihydroxy cinnamic acid (DHCA, commonly known as caffeic acid) exhibited better interactions with HDAC2 (compared to other isoforms) in silico and inhibited its activity ex vivo as well as in vitro. Targeted reduction of HDAC activity using DHCA induced death of cancer cells by (a) generating reactive oxygen species, (b) arresting cells in S and G2/M phases; and (c) induction of caspase-3 mediated apoptosis. In conclusion, we demonstrated that DHCA inhibited cancer cell growth by binding to HDAC followed by the induction of apoptosis.

Synthesis, characterization, and evaluation of Cd[L-proline]2, a novel histone deacetylase inhibitor that induces epigenetic modification of histone deacetylase isoforms in A549 cells

Histone deacetylases (HDACs) play an important role in the epigenetic regulation of gene expression through their effects on the compact chromatin structure. In clinical studies, several classes of histone deacetylase inhibitors (HDACi) have demonstrated potent anticancer activities with metal complexes. Hence, we synthesized cadmium-proline complexes using both the D- and L-isomers of proline and evaluated their biological activities by observing the efficiency of their inhibition of HDAC activity, ability to reduce the expression of HDAC isoforms in A549 cells and effect on apoptosis. The synthesized compounds were characterized by UV, IR, NMR spectroscopy and elemental analysis. In-vitro cell toxicity was evaluated by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, and the 50% inhibitory concentration (IC₅₀; 2 μM) was obtained at 12 h. The morphological study at nuclear levels was performed by acridine orange/ethidium bromide (AO/EB) and Hoechst staining, and the results showed an association with cell cycle arrest at the G2/M phase. Both cadmium-proline complexes intensely inhibited HDAC activity at 2 μM concentration. Interestingly, Cd[L-proline]₂ was found to be a potent inhibitor for all HDAC isoforms, whereas Cd[D-proline]₂ inhibited only HDAC1 and 2. HDACi are novel chemotherapeutic drugs that induce hyperacetylation of histones H3 and H4, counteracting the aberrant repression of genes, such as insulin-like growth factor-binding protein 3 (IGFBP-3), p53, and p21. ERK/MAPK signaling pathway resulted in the downregulation of the expression of matrix metalloproteinases 2 and 9 (MMP-2 and MMP-9), contributing to the inhibition of metastasis in A549 cells. Apoptosis induction was accompanied by the activation of death receptors and their ligands which recruit initiator caspase 8, decrease in mitochondrial membrane potential (ΔΨm), as well as increased Bax/Bcl₂ ratio, followed by activation of caspases 9 and 3. Our finding suggests that Cd[L-proline]₂ complex accelerates epigenetic rearrangement by HDAC inhibition, which may be the key mechanism for its anticancer activity.

Naturally occurring benzoic acid derivatives retard cancer cell growth by inhibiting histone deacetylases (HDAC)

Histone deacetylases (HDACs), which modulate the expression of genes, are potential therapeutic targets in several cancers. Targeted inhibition of HDAC prevents the expression of oncogenes thereby help in the treatment of cancers. Hence, several pharmaceutical companies developed inhibitors of HDAC and tested them in preclinical models and in clinical trials. SAHA (suberanilohydroxamic acid) is one such HDAC inhibitor developed for treating breast and colorectal carcinomas. However, due to poor efficacy in clinical trials the utility of SAHA for treating cancers was discouraged. Similarly another HDAC inhibitor Trichostatin-A (TSA) also showed promising results in clinical trials but exhibited severe adverse effects, which dampened the interest of using this molecule for cancer treatment. Therefore, search for developing a potent HDAC inhibitor with minimal side effects still continues. Hence, in this study we have screened benzoic acid and benzoic acid derivatives with hydroxylic (-OH) groups and methoxy (-OCH3) groups for their efficacy to bind to the TSA binding site of HDAC using molecular docking studies. Molecules that showed much stronger affinity (than TSA) to HDAC were tested for inhibiting HDAC expressing cultured cancer cells. DHBA but not Dimethoxy Benzoic Acid (DMBA) inhibited HDAC activity, leading to cancer cell growth inhibition through the induction of ROS and cellular apoptosis mediated by Caspase-3. In addition, DHBA arrested cells in G2/M phase of the cell cycle and elevated the levels of sub-G0-G1 cell population. In summary, results of this study report that DHBA could be a strong HDAC inhibitor and inhibit cancer cell growth more effectively.

IL-17A promotes the proliferation of human nasopharyngeal carcinoma cells through p300-mediated Akt1 acetylation

Interleukin (IL)-17A is a T helper (Th)17 cell-secreted cytokine that is able to induce various inflammatory responses. There is emerging evidence that IL-17A is generated in the cancer microenvironment of human nasopharyngeal carcinoma (NPC). However, the role of IL-17A in NPC remains unclear. Thus, the present study aimed to examine the direct influence of IL-17A stimulation on the proliferation of human NPC cells and identify the underlying molecular mechanisms. Furthermore, E1A binding protein p300 (p300)-mediated AKT serine/threonine kinase 1 (Akt1) acetylation and its role in regulating the proliferation of NPC cells was investigated. The results of the current study demonstrated that IL-17A stimulation in vitro increased the proliferation of human NPC cells. Furthermore, Akt1 acetylation was identified to be enhanced in human NPC cells induced by IL-17A. Additionally, p300 induction was demonstrated to be required for Akt1 acetylation in human NPC cells following exposure to IL-17A. Functionally, p300-mediated Akt1 acetylation contributed to the proliferation of human NPC cells stimulated by IL-17A. In conclusion, the results of the present demonstrate a novel activity of IL-17A that promotes human NPC cell proliferation via p300-mediated Akt1 acetylation. This may provide a potential strategy for the treatment of patients with NPC through the inhibition of IL-17A or its receptors.

Biogenic gold nanoparticles induce cell cycle arrest through oxidative stress and sensitize mitochondrial membranes in A549 lung cancer cells

Schematic representation of biogenic synthesized AuNPs have been proven to have excellent anticancer activity against A549 human lung cancer cells.

Carfilzomib combined with suberanilohydroxamic acid (SAHA) synergistically promotes endoplasmic reticulum stress in non-small cell lung cancer cell lines

PURPOSE

The endoplasmic reticulum (ER) stress response is a therapeutic target for pharmacologic intervention in cancer cells. We hypothesized that combining carfilzomib (CFZ), a proteasome inhibitor, and vorinostat (SAHA), a histone deacetylase (HDAC) inhibitor, would synergistically activate ER stress in non-small cell lung cancer (NSCLC) cell lines, resulting in enhanced anti-tumor activity.

METHODS

Five NSCLC cell lines were treated with CFZ, SAHA, or the combination and cell proliferation measured using the MTT assay. Calcusyn software was utilized to determine the combination index as a measure of synergy. Cell viability and cytotoxicity were measured using trypan blue exclusion, CellTiter, and CytoTox assays. Western blot was used to measure markers of apoptosis, ER stress, and oxidative stress-related proteins. Reactive oxygen species (ROS) was measured using the fluorophore CM-H2DCFDA.

RESULTS

Synergistic activity was observed for all cell lines following 48 and 72 h of combined treatment. H520 and A549 cell lines were used to assess viability and apoptosis. In both cell lines, increased death and cleaved caspase-3 were observed following combination treatment as compared with single-agent treatments. Combination therapy was associated with upregulation of ER stress-regulated proteins including activating transcription factor 4, GRP78/BiP, and C/EBP homologous protein. Both cell lines also showed increased ROS and the oxidative stress-related protein, heat shock protein 70.

CONCLUSION

Combining proteasome inhibition with HDAC inhibition enhances ER stress, which may contribute to the synergistic anticancer activity observed in NSCLC cell lines. Further preclinical and clinical studies of CFZ + SAHA in NSCLC are warranted.

Hesperidin from Citrus seed induces human hepatocellular carcinoma HepG2 cell apoptosis via both mitochondrial and death receptor pathways

Citrus seeds are full of phenolic compounds, such as flavonoids. The aims of this study were to identify the types of flavonoids in Citrus seed extracts, the cytotoxic effect, mode of cell death, and signaling pathway in human hepatic cancer HepG2 cells. The flavonoids contain anticancer, free radical scavenging, and antioxidant activities. Neohesperidin, hesperidin, and naringin, active flavanone glycosides, were identified in Citrus seed extract. The cytotoxic effect of three compounds was in a dose-dependent manner, and IC50 levels were determined. The sensitivity of human HepG2 cells was as follows: hesperidin > naringin > neohesperidin > naringenin. Hesperidin induced HepG2 cells to undergo apoptosis in a dose-dependent manner as evidenced by the externalization of phosphatidylserine and determined by annexin V-fluorescein isothiocyanate and propidium iodide staining using flow cytometry. Hesperidin did not induce the generation of reactive oxygen species, which was determined by using 2',7'-dichlorohydrofluorescein diacetate and flow cytometry method. The number of hesperidin-treated HepG2 cells with the loss of mitochondrial transmembrane potential increased concentration dependently, using 3,3'-dihexyloxacarbocyanine iodide employing flow cytometry. Caspase-9, -8, and -3 activities were activated and increased in hesperidin-treated HepG2 cells. Bcl-xL protein was downregulated whereas Bax, Bak, and tBid protein levels were upregulated after treatment with hesperidin in a dose-dependent manner. In conclusion, the bioflavanone from Citrus seeds, hesperidin, induced human HepG2 cell apoptosis via mitochondrial pathway and death receptor pathway. Citrus seed flavonoids are beneficial and can be developed as anticancer drug or food supplement, which still needs further in vivo investigation in animals and human beings.