Normal BEAS-2B Cells Research Articles

Cyclometalated Ru(II) β-carboline complexes induce cell cycle arrest and apoptosis in human HeLa cervical cancer cells via suppressing ERK and Akt signaling.

Two new cyclometalated Ru(II)-β-carboline complexes, [Ru(dmb)2(Cl-Ph-βC)](PF6) (dmb = 4,4'-dimethyl-2,2'-bipyridine; Cl-Ph-βC = Cl-phenyl-9H-pyrido[3,4-b]indole; RuβC-3) and [Ru(bpy)2(Cl-Ph-βC)](PF6) (bpy = 2,2'-bipyridine; RuβC-4) were synthesized and characterized. The Ru(II) complexes display high cytotoxicity against HeLa cells, the stabilized human cervical cancer cell, with IC50 values of 3.2 ± 0.4μM (RuβC-3) and 4.1 ± 0.6μM (RuβC-4), which were considerably lower than that of non-cyclometalated Ru(II)-β-carboline complex [Ru(bpy)2(1-Py-βC)] (PF6)2 (61.2 ± 3.9μM) by 19- and 15-folds, respectively. The mechanism studies indicated that both Ru(II) complexes could significantly inhibit HeLa cell migration and invasion, and effectively induce G0/G1 cell cycle arrest. The new Ru(II) complexes could also trigger apoptosis through activating caspase-3 and poly (ADP-ribose) polymerase (PARP), increasing the Bax/Bcl-2 ratio, enhancing reactive oxygen species (ROS) generation, decreasing mitochondrial membrane potential (MMP), and inducing cytochrome c release from mitochondria. Further research revealed that RuβC-3 could deactivate the ERK/Akt signaling pathway thus inhibiting HeLa cell invasion and migration, and inducing apoptosis. In addition, RuβC-3-induced apoptosis in HeLa cells was closely associated with the increase of intracellular ROS levels, which may act as upstream factors to regulate ERK and Akt pathways. More importantly, RuβC-3 exhibited low toxicity on both normal BEAS-2B cells in vitro and zebrafish embryos in vivo. Consequently, the developed Ru(II) complexes have great potential on developing novel low-toxic anticancer drugs.

Design, synthesis and in vitro anticancer research of novel tetrandrine and fangchinoline derivatives

Cancer treatment is one of the major public health issues in the world. Tetrandrine (Tet) and fangchinoline (d-Tet) are two bis-benzyl isoquinoline alkaloids extracted from Stephania tetrandra S. Moore, and their antitumor activities have been confirmed. However, the effective dose of Tet and d-Tet were much higher than that of the positive control and failed to meet clinical standards. Therefore, in this study, as a continuation of our previous work to study and develop high-efficiency and low-toxic anti-tumor lead compounds, twenty new Tet and d-Tet derivatives were designed, synthesized and evaluated as antitumor agents against six cancer cell lines (H460, H520, HeLa, HepG-2, MCF-7, SW480 cell lines) and BEAS-2B normal cells by CCK-8 analysis. Ten derivatives showed better cytotoxic effects than the parent fangchinoline, of which 4g showed the strongest cell growth inhibitory activity with an IC50 value of 0.59 μM against A549 cells. Subsequently, the antitumor mechanism of 4g was studied by flow cytometry, Hoechst 33258, JC-1 staining, cell scratch, transwell migration, and Western blotting assays. These results showed that compound 4g could inhibit A549 cell proliferation by arresting the G2/M cell cycle and inhibiting cell migration and invasion by reducing MMP-2 and MMP-9 expression. Meanwhile, 4g could induce apoptosis of A549 cells through the intrinsic pathway regulated by mitochondria. In addition, compound 4g inhibited the phosphorylation of PI3K, Akt and mTOR, suggesting a correlation between blocking the PI3K/Akt/mTOR pathway and the above antitumor activities. These results suggest that compound 4g may be a future drug for the development of new potential drug candidates against lung cancer.

Silencing Sirtuin 6 induces cell cycle arrest and apoptosis in non-small cell lung cancer cell lines

Sirtuins (SIRT1–7), are NAD-dependent deacetylases and ADP-ribosyl transferases, plays a major part in carcinogenesis. The previous report suggests that in cancer, sirtuins gained tremendous interest and critical regulators of the unusual processes. In carcinogenesis, sirtuins possess either tumor suppressor or promoter. However, in lung cancer condition the studies of sirtuins are less studied. Hence, this designed study investigates the impact of multifaceted sirtuins in NSCLC cells. We evaluated the mRNA and protein expressions of sirtuins by RTPCR and western blot. We found SIRT6 significantly overexpressed in NCI-H520, A549, and NCI-H460 compared with the normal BEAS-2B cell line. Silencing of SIRT6 by siRNA in NSCLC cells caused activation of p53/p21 mediated inhibition of cell proliferation leading to arrest in cell cycle and apoptosis induction. Our results implied that SIRT6 is a tumor promoter in NSCLC development, progression, and regulation. The silencing of SIRT6 to be a novel therapy for lung cancer.

Toxicity of fine and quasi-ultrafine particles: Focus on the effects of organic extractable and non-extractable matter fractions.

To date no study has been able to clearly attribute the observed toxicological effects of atmospheric particles (PM) to a specific class of components. The toxicity of both the organic extractable matter (OEM2.5-0.3) and non-extractable matter (NEM2.5-0.3) of fine particles (PM2.5-0.3) was compared to that of PM2.5-0.3 in its entirety on normal human epithelial bronchial BEAS-2B cells in culture. The specific effect of the quasi-ultrafine fraction (PM0.3) was assessed, by comparing the responses of cells exposed to the PM2.5-0.3 and PM0.3 organic extractable matter, OEM2.5-0.3 and OEM0.3 respectively. Chemically, PAH, O-PAH, and N-PAH were respectively 43, 17, and 4 times more concentrated in PM0.3 than in PM2.5-0.3, suggesting thereby a predominant influence of anthropogenic activities and combustion sources. BEAS-2B cells exposed to PM2.5-0.3, NEM2.5-0.3, EOM2.5-0.3 and OEM0.3 lead to different profiles of expression of selected genes and proteins involved in the metabolic activation of PAH, O-PAH, and N-PAH, and in the genotoxicity pathways. Specifically, OEM0.3 was the most inducer for phase I and phase II enzymes implicated in the metabolic activation of PAH (AHR, AHRR, ARNT, CYP1A1, CYP1B1, EPHX-1, GSTA-4) thereby producing the highest DNA damage, felt by ATR and, thereafter, a cascade of protein phosphorylation (CHK1/CHK2/MDM2) closely related to the cell cycle arrest (P21 and P53 induction). This study underlined the crucial role played by the organic chemicals present in PM0.3. These results should be considered in any future study looking for the main chemical determinants responsible for the toxicity of ambient fine PM.

LINC00958 Accelerates Cell Proliferation and Migration in Non-Small Cell Lung Cancer Through JNK/c-JUN Signaling

Non-small cell lung cancer (NSCLC) denotes the most common type of lung cancers with high mortality globally. Long non-coding RNAs (lncRNAs) with differential expression have been indicated to be participants in the pathogenesis and development of cancer. However, the precise role of lncRNAs in NSCLC is still largely obscure. In this study, we explored a newly discovered intergenic lncRNA LINC00958 in NSCLC. First of all, the online databases suggested that LINC00958 was slightly expressed in human normal lung tissues but upregulated in LUSC tissues. Besides, the upregulation of LINC00958 in both lung adenocarcinoma (LUAD) and LUSC cell lines was easily found when compared with the normal BEAS-2B cells. In addition, we elucidated that knockdown of LINC00958 led to impaired proliferation, induced apoptosis, and hampered migration in LUAD cells. Moreover, a typical oncogenic pathway, JNK signaling, was verified to be involved in LINC00958-contributed LUAD development. Of note, we explained that LINC00958 exerted the tumor-promoting function in LUAD by enhancing the transactivation of p-c-JUN through activating JNK signaling. Meanwhile, we also revealed that LINC00958 was transcriptionally regulated by c-JUN. In addition, earlier findings were also suitable for LUSC cells. By and large, our work illustrated that LINC00958 facilitates tumorigenesis in NSCLC by activating the JNK/c-JUN signaling pathway, indicating a new road for diagnosis and treatment of both LUAD and LUSC.

LINC00958 accelerates cell proliferation and migration in non-small cell lung cancer through JNK/c-JUN signaling

Non-small cell lung cancer (NSCLC) denotes the commonest type of lung cancers with high mortality globally. Long non-coding RNAs (lncRNAs) with differential expression have been indicated to be participants in the pathogenesis and development of cancer. However, the precise role of lncRNAs in NSCLC is still largely obscure. In this study, we explored a newly-discovered intergenic lncRNA LINC00958 in NSCLC. First of all, the online databases suggested that LINC00958 was low expressed in human normal lung tissues but upregulated in LUSC tissues. Besides, the upregulation of LINC00958 in both LUAD and LUSC cell lines was easily found when comparing to the normal BEAS-2B cells. In addition, we elucidated that knockdown of LINC00958 led to impaired proliferation, induced apoptosis and hampered migration in LUAD cells. Moreover, a typical oncogenic pathway, JNK signaling, was verified to be involved in LINC00958-contributed LUAD development. Of note, we explained that LINC00958 exerted the tumor-promoting function in LUAD by enhancing the transactivation of p-c-JUN through activating JNK signaling. Meanwhile, we also revealed that LINC00958 was transcriptionally regulated by c-JUN. Additionally, above findings were also suitable for LUSC cells. By and large, our work illustrated that LINC00958 facilitates tumorigenesis in NSCLC by activating JNK/c-JUN signaling pathway, indicating a new road for diagnosis and treatment of both LUAD and LUSC.

LncRNA LINC00857 regulates lung adenocarcinoma progression, apoptosis and glycolysis by targeting miR-1179/SPAG5 axis.

Long non-coding RNA (lncRNA), a member of non-coding RNA family with over 200 nucleotides in length, typically serves as an oncogene or tumor suppressor in tumor progression, such as cancer cell proliferation, apoptosis and glycolysis. Recent studies manifested lncRNA LINC00857 was involved in cell cycle regulation of lung cancer. Due to complicated networks in tumorigenesis, the potential roles of LINC00857 underlying lung cancer progression still need further investigation. In this study, we explored the expression of LINC00857 in lung adenocarcinoma (LUAD) tissues and LUAD cell lines and found a dramatical upregulation of LINC00857 compared with the adjacent normal lung tissues and BEAS-2B cell line, respectively. Then, LINC00857 knockdown led to the cell proliferation and glycolysis was repressed, while the apoptosis was elevated in LUAD cell lines. Furthermore, we identified a direct interaction between LINC00857 and miR-1179 in LUAD cells using bioinformatic method and report assay. Finally, we evidenced LINC00857 promoted cell growth and glycolysis and repressed apoptosis via sponging miR-1179 and further regulating sperm-associated antigen 5 (SPAG5) expression in LUAD cell lines. Hence, our results authenticated that lncRNA LINC00857 regulated the cell proliferation, glycolysis and apoptosis of LUAD cells mainly through targeting the miR-1179/SPAG5 axis, which might be a novel insight into lung cancer progression and provided a potential target for clinical treatment of LUAD patients.

MicroRNA and mRNA Interaction Network Regulates the Malignant Transformation of Human Bronchial Epithelial Cells Induced by Cigarette Smoke.

This study analyzes the correlation and interaction of miRNAs and mRNAs and their biological function in the malignant transformation of BEAS-2B cells induced by cigarette smoke (CS). Normal human bronchial epithelial cells (BEAS-2B) were continuously exposed to CS for 30 passages (S30) to establish an in vitro cell model of malignant transformation. The transformed cells were validated by scratch wound healing assay, transwell migration assay, colony formation and tumorigenicity assay. The miRNA and mRNA sequencing analysis were performed to identify differentially expressed miRNAs (DEMs) and differentially expressed genes (DEGs) between normal BEAS-2B and S30 cells. The miRNA-seq data of lung cancer with corresponding clinical data obtained from TCGA was used to further identify lung cancer-related DEMs and their correlations with smoking history. The target genes of these DEMs were predicted using the miRDB database, and their functions were analyzed using the online tool “Metascape.” It was found that the migration ability, colony formation rate and tumorigenicity of S30 cells enhanced. A total of 42 miRNAs and 753 mRNAs were dysregulated in S30 cells. The change of expression of top five DEGs and DEMs were consistent with our sequencing results. Among these DEMs, eight miRNAs were found dysregulated in lung cancer tissues based on TCGA data. In these eight miRNAs, six of them including miR-96-5p, miR-93-5p, miR-106-5p, miR-190a-5p, miR-195-5p, and miR-1-3p, were found to be associated with smoking history. Several DEGs, including THBS1, FN1, PIK3R1, CSF1, CORO2B, and PREX1, were involved in many biological processes by enrichment analysis of miRNA and mRNA interaction. We identified the negatively regulated miRNA-mRNA pairs in the CS-induced lung cancer, which were implicated in several cancer-related (especially EMT-related) biological process and KEGG pathways in the malignant transformation progress of lung cells induced by CS. Our result demonstrated the dysregulation of miRNA-mRNA profiles in cigarette smoke-induced malignant transformed cells, suggesting that these miRNAs might contribute to cigarette smoke-induced lung cancer. These genes may serve as biomarkers for predicting lung cancer pathogenesis and progression. They can also be targets of novel anticancer drug development.

P2.14-50 Low Temperature Plasma Needle Induces Cell Cycle Arrest of Epithelial Lung Cancer Cells in Vitro via a p21-Dependent Pathway

Low temperature plasma sources which operate at atmospheric pressure produce reactive oxygen species (ROS) and reactive nitrogen species which can cause cancer cell death. In this study we investigated the effect of our low temperature plasma needle system on a non-small cell lung cancer cell line A549 and studied its mechanism of action. The housing of the pen lookalike atmospheric plasma source (plasma needle) was made of Teflon. A Pyrex glass tube (o.d. 6 mm and i.d. 4 mm) through which 1 slm of helium was released as the feeding gas was positioned within the housing. The central electrode, a tungsten wire, was powered with a 13.56 MHz sine wave and placed within a ceramic tube inside the glass tube. The central electrode was sticking 1 mm outside of the ceramic and glass tubes, so the discharge occurred on its tip as a weak glow. The cytotoxic activity was determined using MTT assay. The potential of inducing cell cycle perturbations and apoptosis, and changes in the level of ROS was investigated by flow cytometry. The influence of plasma treatment on growth inhibition of multicellular tumor spheroids (MCTS) was also investigated. Evaluation of gene expression was performed by qPCR. All experiments were performed in triplicate, with statistical significance set at p<0.05. Our plasma needle exerted a cytotoxic effect with lower sensitivity towards BEAS-2B normal cells than towards A549 cells. A decrease in the number of cells in the G1 phase (up to 45%), increase in the G2 phase (up to 27%), and an increase in the sub-G1 phase (up to 12%) with fragmented DNA was detected upon treatment. The plasma treatment exerted a mild apoptotic effect (around 15% of apoptotic cells), and an increase in the level of ROS in a power dependent manner. There was no significant reduction in growth of MCTS after plasma treatment under investigated experimental conditions. A statistically non-significant proapoptotic effect (increase in Bax, decrease in Bcl2 and decrease in SKP2) was observed at the genetic level. A significant overexpression of the cyclin-dependent kinase inhibitor 1 (p21) was also observed at the genetic level in a power dependent manner. Our low temperature plasma needle induced cell cycle arrest of epithelial lung cancer cells through overexpression of p21. The effect of combined plasma treatment with existing treatment modalities (cisplatin, PARP inhibitors) is currently under in vitro investigation.

Mechanism of VIPR1 gene regulating human lung adenocarcinoma H1299 cells.

The vasoactive intestinal peptide receptor-1(VIPR1) has prominent growth effects on a number of common neoplasms. However, there were contradictions in the effect cross different cancers. We aimed to explore the effect of VIPR1 overexpression on a human lung adenocarcinoma cell line H1299. GEO dataset was used to screen differentially expressed genes in lung adenocarcinoma tissues. The expression of VIPR1 mRNA was determined in the cancer Genome Atlas (TCGA). Immunohistochemical analysis was performed to determine VIPR1 protein expression in lung adenocarcinoma and corresponding adjacent tissues (n = 22). Fluorescence real-time quantitative PCR detected the expression of VIPR1 in human normal lung epithelial cell line BEAS-2B and lung adenocarcinoma cell line H1299. Overexpression strategies were employed to assess functions of VIPR1 expression on several malignant phenotypes in H1299. The expression of VIPR1 was lower in lung adenocarcinoma tissues than that in adjacent tissues. Compared with the normal lung epithelial cells BEAS-2B, VIPR1 was down-regulated in lung cancer cells H1299 (P < 0.05). After the overexpression of VIPR1, we found that VIPR1 significantly inhibited growth, migration, and invasion of H1299 cells (P < 0.05). Our findings point out the tumor suppressor roles of VIPR1 in human LUAD pathogenesis.

The Anticancer and Anti-inflammatory Effects of Centaurea solstitialis Extract on Human Cancer Cell Lines.

Natural products originating from plants have been used for many years in the treatment of various diseases, including cancer. Centaurea solstitialis subsp. solstitialis is used in Turkish folk medicine. This study was the first to determine the in vitro biological effects of ethanolic extract from the flowering parts of C. solstitialis L. subsp. solstitialis collected from Muğla Province. The cytotoxic effect was evaluated against Daudi, A549, and HeLa cancer cells and one normal BEAS-2B cell line using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5- dipenyltetrazolium bromide) assay. Flow cytometric analysis and the caspase-3 activity assay were performed to detect apoptotic cell death. Angiogenic factor [vascular endothelial growth factor (VEGF)] secretion and the release of interleukin (IL)-1α, IL-6, and tumor necrosis factor (TNF)-α by cells treated with the extract were measured using enzyme-linked immunosorbent assay. The extract exhibited cytotoxic effects against all the cancer cell lines used but HeLa and Daudi were the most sensitive cells, with IC50 values of 63.18 μg/mL and 69.27 μg/mL, respectively. Selective cytotoxicity was observed between the HeLa and normal BEAS-2B cell lines. The extract arrested the cell cycle at the S and G2 phases. In addition, apoptotic cell death was detected in HeLa and A549 cells. Moreover, the plant extract caused a significant decrease in VEGF secretion in A549 cells and a fluctuation in IL-1α, IL-6, and TNF-α secretion in A549 and Daudi cells. These observations suggest that the flowering parts of C. solstitialis may be a potential source in the development of natural drugs for the treatment of cancer and modulation of cytokine secretion.

Selective cytotoxicity and antifungal properties of copper(II) and cobalt(II) complexes with imidazole-4-acetate anion or 1-allylimidazole

The physicochemical properties of metal complexes determine their potential applications as antitumor agents. In this study, the antitumor properties of mononuclear cobalt(II) and copper(II) coordination compounds (stoichiometry: [Co(iaa)2(H2O)2]·H2O (iaa = imidazole-4-acetate anion), [Co(1-allim)6](NO3)2 (1-allim = 1-allylimidazole), [Cu(iaa)2H2O] and [Cu(1-allim)4(NO3)2]) and their ligands have been evaluated on human lung carcinoma A549 cells and normal bronchial BEAS-2B cells. Designing the chemical structure of new antitumor agents the possible interactions with macromolecules such as DNA or proteins should be take into account. PCR gene tlr4 product served as DNA model, whereas lysozyme and phage-derived endolysin (both peptidoglycan degrading enzymes) were applied as protein/enzyme model. The interactions were analysed using PCR-HRM and circular dichroism, FT-IR, spectrophotometry, respectively. Additionally, the antimicrobial properties of the complexes at a non-cytotoxic concentration were analyzed against S. aureus, E. coli, P. aeruginosa and C. albicans strains. The results obtained in this study showed the selective cytotoxicity of metal complexes, mainly [Cu(1-allim)4(NO3)2] towards tumor cells. From all tested compounds, only [Co(iaa)2(H2O)2].H2O non-covalently interacts with DNA. Cu(II) and Co(II) complexes did not affect the secondary conformation of tested proteins but modified the hydrolytic activity of enzymes (lysozyme and endolysin). Moreover, only [Co(iaa)2(H2O)2].H2O exhibited the antifungal properties. In conclusion, Co(II) and Cu(II) metal complexes bearing two imidazole-4-acetate ligands seemed to be promising antitumor and antifungal agents for future drug design and application.

Abstract 2063: GO-Chl induce necroptosis death in A549 lung cancer cells through p62/SQSTM1 mediated DNA damage response

Abstract Autophagy is a highly regulated intracellular catabolic pathway for maintenance of cell homeostasis through the process of degrading proteins and organelles. Inhibition or modulation of autophagy may leads to accumulation of DNA damage and genomic instability. Recently, it has been reported that DNA damage or repair response by autophagy machinery can switch the cell signalling cascade from apoptosis to necroptosis. The synergistic effect of autophagy machinery with DNA damage pathways may provide a therapeutic window for next generation nanomedicine. Graphene oxide (GO) alters the autophagy response through toll like receptor signaling, lysosomal dysfunction, mitochondrial destabilization and NF- κB pathways. On the other hand, Chloroquine (Chl) an FDA approved drug inhibits the autophagy and has also shown anticancer potential. In the present study, we endeavored the conjugation of Chl onto GO nanosheets and evaluated the antiproliferative efficacy of GO-Chl nanoconjugate on human lung cancer A549 and normal lung BEAS-2B cell lines. Morphological properties of GO and GO-Chl have been analyzed through TEM, FESEM and AFM and formation of nearly monolayer highly exfoliated GO nanosheets has been observed. Further, structural, functional and optical properties of GO, Chl and GO-Chl have been investigated using Raman, FTIR and UV-Vis spectroscopy respectively. MTT assay has been performed for in- vitro cytotoxicity evaluation of GO, Chl and GO-Chl exposure on A549 and BEAS-2B cell lines and demonstrated that GO-Chl treatment exhibits significant cell death in A549 lung cancer cells. DCFDA assay reveals that GO-Chl exposure enhance generation of ROS. Flow cytometry based Propidium Iodide (PI) assay reveals the plasma membrane disruption leading to alteration in the cell cycle. Further, flow cytometry based annexin V/PI assay for cell cycle analysis indicate towards the halts of the cell cycle at G1 phase and possible DNA damage response. The integrity of A549 cells DNA was accesed using Comet assay. The results reveals a significant increase in Olive tail moment with increasing concentration of GO-Chl. Further, the autophagy response in A549 cells due to GO-Chl treatment is investigated through fluorescence microscopic analysis (MDC staining and GFP-LC3 plasmid), TEM observations and immunoblot analysis. Enhanced level of LC-3 I/II and Atg-5 markers signifies the autophagosomes formation and elevated expression of p62/SQSTM1 indicates the inhibition of autophagy at later stage. Recently, it was reported that enhanced level of p62/SQSTM1 may inhibit the DNA repair mechanism leading to decreased growth in-vitro and in-vivo. On the basis of results obtained, it is envisioned that GO-Chl nanoconjugate could be used as an effective cancer therapeutic agent, by targeting the DDR response through modualtion of autophagy. Note: This abstract was not presented at the meeting. Citation Format: Braham D. Arya, Surinder P. Singh. GO-Chl induce necroptosis death in A549 lung cancer cells through p62/SQSTM1 mediated DNA damage response [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 2063.

Constitutive Activation of NAD-Dependent Sirtuin 3 Plays an Important Role in Tumorigenesis of Chromium(VI)-Transformed Cells.

Chronic exposure of human bronchial epithelial BEAS-2B cells to hexavalent chromium [Cr(VI)] causes malignant cell transformation. Sirtuin-3 (SIRT3) regulates mitochondrial adaptive response to stress, such as metabolic reprogramming and antioxidant defense mechanisms. In Cr(VI)-transformed cells, SIRT3 was upregulated and mitochondrial adenosine triphosphate (ATP) production and proton leak were reduced. Knockdown of SIRT3 by its shRNA further decreased mitochondrial ATP production, proton leak, mitochondrial mass, and mitochondrial membrane potential, indicating that SIRT3 positively regulates mitochondrial oxidative phosphorylation and maintenance of mitochondrial integrity. Mitophagy is critical to maintain proper cellular functions. In Cr(VI)-transformed cells expressions of Pink 1 and Parkin, twomitophagy proteins, were elevated, and mitophagy remained similar as that in passage-matched normal BEAS-2B cells, indicating that in -Cr(VI)-transformed cells mitophagy is suppressed. Knockdown of SIRT3 induced mitophagy, suggesting that SIRT3 plays an important role in mitophagy suppression of Cr(VI)-transformed cells. In Cr(VI)-transformed cells, nuclear factor (erythroid-derived 2)-like 2 (Nrf2) was constitutively activated, and protein levels of p62 and p-p62Ser349 were elevated. Knockdown of SIRT3 or treatment with carbonyl cyanide m-chlorophenyl hydrazone (CCCP) decreased the binding of p-p62Ser349 to Keap1, resulting in increased binding of Keap1 to Nrf2 and consequently reduced Nrf2 activation. The results from CHIP assay showed that in Cr(VI)-transformed cells binding of Nrf2 to antioxidant response element (ARE) of SIRT3 gene promoter was dramatically increased. Knockdown of SIRT3 suppressed cell proliferation and tumorigenesis of Cr(VI)-transformed cells. Overexpression of SIRT3 in normal BEAS-2B cells exhibited mitophagy suppression phenotype and increased cell proliferation and tumorigenesis. The present study demonstrated that upregulation of SIRT3 causes mitophagy suppression and plays an important role in cell survival and tumorigenesis of Cr(VI)-transformed cells.

Fusigen Reduces Intracellular Reactive Oxygen Species and Nitric Oxide Levels.

Oxidative stress caused by the production of excessive cellular reactive oxygen species (ROS) and high levels of nitric oxide contribute to several human pathologies. This study aimed to examine the anti-oxidant effects of fusigen, a compound produced from Aureobasidium melanogenum. Extracts of A. melanogenum were selected as a source for the isolation of fusigen. The anti-oxidant, nitric oxide suppression, as well as the free radical scavenging activities of fusigen were tested in BEAS-2B human bronchial epithelial cell line (BEAS-2B cells) and human dermal papilla cells (DP cells) using specific fluorescence dyes and flow cytometry analysis. Cell viability was determined by the MTT assay. Fusigen did not exert cytotoxicity in the human normal BEAS-2B and DP cells at concentrations up to 100 μM. Fusigen decreased basal levels of cellular ROS, as well as the levels of ROS induced by hydrogen peroxide and ferrous ion enrichment. ROS decreasing effect was confirmed in DP cells. In addition, fusigen treatment suppressed intracellular NO levels in both BEAS-2B and DP cells. The optimal process of production of purified fusigen from A. melanogenum was determined. Fusigen exhibited a low cytotoxic effect and the potential to suppress ROS and NO. These results demonstrated that fusigen may be used for the treatment or prevention of human diseases.

Cytotoxicity comparison between fine particles emitted from the combustion of municipal solid waste and biomass.

Fine particles (PM2.5) emitted from municipal solid waste incineration (MSWI) contain high amounts of toxic compounds and pose a serious threat to environment and human health. In this study, entire particles as well as extracted water-soluble and -insoluble fractions of PM2.5 collected from MSWI and biomass incineration (BMI) were subjected to physiochemical characterization and cytotoxic tests in A549 and BEAS-2B cells. MSWI PM2.5 had higher contents of heavy metals (including Pb, Zn, and Cu) and dioxins (PCDD/Fs) than did BMI PM2.5. The metals were enriched in the water-insoluble fraction, as measured by inductively coupled plasma-atomic emission spectrometry. BMI PM2.5 had a higher content of endotoxin, which was also enriched in the water-insoluble fraction. MSWI PM2.5 caused more serious cell injuries, as indicated by the lower viability, higher ROS generation, and DNA damage, whereas BMI PM2.5 presented higher pro-inflammatory potential, as indicated by increased mRNA levels of interleukin 6. Normal human BEAS-2B cells were more sensitive than A549 cells in all these tests. Toxic effects caused by MSWI and BMI PM2.5 were mostly attributable to their water-insoluble fractions. Our results indicate different chemical and biological compositions in MSWI and BMI PM2.5 probably dominate in different toxic endpoints in vitro.

Switchable Photoacoustic Imaging of Glutathione Using MnO2 Nanotubes for Cancer Diagnosis.

Glutathione is overexpressed in tumor cells and regulates cancer growth, metastasis, and drug resistance. Therefore, detecting glutathione levels may greatly facilitate cancer diagnosis and treatment response monitoring. Photoacoustic (PA) imaging is a noninvasive modality for high-sensitivity, high-resolution, deep-tissue optical imaging. Switchable PA probes that offer signal on/off responses to tumor targets would further improve the detection sensitivity and signal-to-noise ratio of PA imaging. Here, we explore the use of MnO2 nanotubes as a switchable and biodegradable PA probe for dynamic imaging of glutathione in cancer. Glutathione reduces black MnO2 nanotubes into colorless Mn2+ ions, leading to decreased and signal off PA amplitude. In phantoms, we observed a linear response of reduced PA signals of MnO2 nanotubes to increased glutathione concentrations. Using melanoma as the disease model, we demonstrated that MnO2 nanotube-based PA imaging of glutathione successfully distinguished B16F10 melanoma cells from BEAS-2B normal cells and discriminated B16F10 tumors from healthy skin tissues. Our results showed that MnO2 nanotubes are a potent switchable and biodegradable PA probe for glutathione imaging in cancer diagnosis.

Synthesis, physicochemical and biological characterization of Ni(II) complex with imidazole-4-acetate anion as new antifungal agent

The neutral mononuclear nickel(II) complex with an imidazole-4-acetate anion (iaa), having the formula $$[\hbox {Ni(iaa)}_{2}(\hbox {H}_{{2}}\hbox {O})_{2}]{\cdot }\hbox {H}_{{2}}\hbox {O}$$ , was characterized by single-crystal X-ray diffraction, IR, farIR, UV-Vis-NIR spectra and magnetic measurements. The imidazole-4-acetate anion in this complex is a chelating ligand where an azomethine nitrogen atom of the imidazole ring and carboxylate oxygen atoms are donor atoms. The immediate environment of the central nickel(II) ion is described by distorted cis-octahedron ( $$\hbox {NiN}_{{2}}\hbox {O}_{4}$$ chromophore). The analysis of biological properties of $$[\hbox {Ni(iaa)}_{2}(\hbox {H}_{{2}}\hbox {O})_{2}] {\cdot } \hbox {H}_{{2}}\hbox {O}$$ complex has shown that this complex at non-cytotoxic concentration against normal human BEAS-2B cell has antifungal properties. The biophysical studies have shown that of [ $$[\hbox {Ni(iaa)}_{2}(\hbox {H}_{{2}}\hbox {O})_{2}] {\cdot } \hbox {H}_{{2}}\hbox {O}$$ ] interacts with DNA without degradation and with BSA as a model protein. SYNOPSIS Synthesis and characterization of neutral mononuclear nickel(II) complex with imidazole-4-acetate anion (iaa) is reported. The results suggest that $$[\hbox {Ni(iaa)}_{2}(\hbox {H}_{{2}}\hbox {O})_{2}] {\cdot } \hbox {H}_{{2}}\hbox {O}$$ complex interacts weakly with DNA via weak intercalative or groove binding mode. The ability of nickel(II) complex to bind to protein (BSA) has been confirmed in this study. From biological point of view, $$[\hbox {Ni(iaa)}_{2}(\hbox {H}_{{2}}\hbox {O})_{2}] {\cdot } \hbox {H}_{{2}}\hbox {O}$$ complex has antifungal properties at non-cytotoxic concentration against normal human cell line.

Synthesis and anticancer activity of dimeric podophyllotoxin derivatives.

BackgroundPodophyllotoxin is a potent cytotoxic agent and serves as a useful lead compound for the development of antitumor drugs. Several podophyllotoxin-derived antitumor agents, including etoposide, are currently in clinical use; however, their therapeutic efficacy is often limited due to side effects and the development of resistance by cancer cells. Previous studies have shown that 4β-1,2,3-triazole derivatives of podophyllotoxin exhibit more potent anticancer activity and better binding to topoisomerase-II than etoposide. The effect of dimerization of such derivatives on the anticancer activity has not been studied.MethodsTwo moieties of podophyllotoxin were linked at the C-4 position via 1,2,3-triazole rings to give a series of novel dimeric podophyllotoxin derivatives. 4β-Azido-substituted podophyllotoxin derivatives (23 and 24) were coupled with various dipropargyl functionalized linkers by utilizing the copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction to provide dimeric products in very good yield. The in vitro anticancer activity of the synthesized compounds was evaluated by MTT assay against a panel of five human cancer cell lines (HL-60, SMMC-7721, A-549, MCF-7, and SW480). The normal BEAS-2B (lung) cell line was also included for study in order to evaluate the cancer selectivity of the most active compound as compared with normal cells.ResultsA group of 16 dimeric podophyllotoxin derivatives with different linkers were synthesized and structurally characterized. Most compounds do not show significant cytotoxicity (IC50 > 40 mM) against all five cancer cell lines. However, one compound (29) which bears a perbutyrylated glucose residue on the glycerol linker is highly potent against all five cancer cell lines tested, with IC50 values ranging from 0.43 to 3.50 μM. This compound (29) also shows good selectivity towards cancer cell lines as compared with the normal BEAS-2B (lung) cell line, showing selectivity indexes from 4.4 to 35.7.ConclusionThe anticancer activity of dimeric podophyllotoxin derivatives is generally speaking not improved as compared to their monomeric counterparts, and the potency of these dimeric derivatives can be largely affected by the nature of the linker between the two moieties. Among the synthesized derivatives, compound 29 is significantly more cytotoxic and selective towards cancer cells than etoposide and cisplatin, which are currently in clinical use. Compound 29 is a promising anticancer drug and needs further studies.

Decoration of Cisplatin on 2D Metal-Organic Frameworks for Enhanced Anticancer Effects through Highly Increased Reactive Oxygen Species Generation.

Herein, a biocompatible 2D metal-organic frameworks (Cu-TCPP(Fe)) based on TCPP(M) (TCPP = tetrakis (4-carboxyphenyl) porphyrin, M = Fe) and copper ion were synthesized as a novel drug carrier. Sequentially, the cisplatin was loaded on the merge of carboxyl-rich Cu-TCPP(Fe) through forming favorable carboxyl-drug interactions. The prepared Pt/Cu-TCPP(Fe) showed highly enhanced cytotoxicity than that of free cisplatin in human pulmonary carcinoma A549 cells, whereas inverse inhibitory effects were observed in human normal BEAS-2B cells. Further, the mechanism of action about the desirable results was also elaborated. Our study highlighted the potential synergies between the nanocarrier and the anticancer drugs.