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Background The aim of this study is to investigate role of Visfatin, one of the pro-inflammatory adipokines, in sepsis-induced intestinal injury and to clarify the potential mechanism. Methods C57BL/6 mice underwent cecal ligation and puncture (CLP) surgery to establish sepsis model in vivo. Intestinal epithelial cells were stimulated with LPS to mimic sepsis-induced intestinal injury in vitro. FK866 (the inhibitor of Visfatin) with or without XMU-MP-1 (the inhibitor of Hippo signaling) was applied for treatment. The expression levels of Visfatin, NF-κB and Hippo signaling pathways-related proteins were detected by western blot or immunohistochemistry. The intestinal cell apoptosis and intestinal injury were investigated by TUNEL staining and H&E staining, respectively. ELISA was used to determine the production of inflammatory cytokines. Results The expression of Visfatin increased in CLP mice. FK866 reduced intestinal pathological injury, inflammatory cytokines production, and intestinal cell apoptosis in sepsis mice. Meanwhile, FK866 affected NF-κB and Hippo signaling pathways. Additionally, the effects of FK866 on inflammatory response, apoptosis, Hippo signaling and NF-κB signaling were partly abolished by XMU-MP-1, the inhibitor of Hippo signaling. In vitro experiments also revealed that FK866 exhibited a protective role against LPS-induced inflammatory response and apoptosis in intestinal cells, as well as regulating NF-κB and Hippo signaling, whereas addition of XMU-MP-1 weakened the protective effects of FK866. Conclusion In short, this study demonstrated that inhibition of Visfatin might alleviate sepsis-induced intestinal injury through Hippo signaling pathway, supporting a further research on Visfatin as a therapeutic target.

Many regulators controlling arterial identity are well described; however, transcription factors that promote vein identity and vascular patterning have remained largely unknown. We previously identified the transcription factors Islet2 (Isl2) and Nr2f1b required for specification of the vein and tip cell identity mediated by notch pathway in zebrafish. However, the interaction between Isl2 and Nr2f1b is not known. In this study, we report that Nr2f2 plays minor roles on vein and intersegmental vessels (ISV) growth and dissect the genetic interactions among the three transcription factors Isl2, Nr2f1b, and Nr2f2 using a combinatorial knockdown strategy. The double knockdown of isl2/nr2f1b, isl2/nr2f2, and nr2f1b/nr2f2 showed the enhanced defects in vasculature including less completed ISV, reduced veins, and ISV cells. We further tested the genetic relationship among these three transcription factors. We found isl2 can regulate the expression of nr2f1b and nr2f2, suggesting a model where Isl2 functions upstream of Nr2f1b and Nr2f2. We hypothsized that Isl2 and Nr2f1b can function together through cis-regulatory binding motifs. In-vitro luciferase assay results, we showed that Isl2 and Nr2f1b can cooperatively enhance gene expression. Moreover, co-immunoprecipitation results indicated that Isl2 and Nr2f1b interact physically. Together, we showed that the interaction of the Nr2f1b and Nr2f2 transcription factors in combination with the Islet2 play coordinated roles in the vascular development of zebrafish.

Semiconducting polymer dots (Pdots) recently have emerged as a new class of extraordinarily bright fluorescent probes with promising applications in biological imaging and sensing. Herein multicolor semiconducting polymer nanoparticles (Pdots) were designed using benzothiadiazole (BT) as the acceptor, and various types of donors were incorporated to modulate their emission wavelengths. Specific cellular targeting and in vivo biotoxicity as well as microangiography imaging on zebrafish indicated these BT-based Pdots are promising candidates for biological applications.

Age-related macular degeneration (AMD) is a disease of retinal pigment epithelium (RPE) cells. We have previously demonstrated that blue light can damage RPE cells and their underlying mechanisms. We found that hexahydrocurcumin (HHC), a metabolite of curcumin, had better retinal protection than curcumin. However, the involved mechanisms remain unclear.By exposing ARPE-19 human RPE cells and mouse primary RPE cells to blue light, the intracellular mechanisms of HHC in cells were investigated, including the proliferation of RPE cells and the effects of HHC on activating intracellular protective mechanisms and related factors. Next-generation sequencing (NGS) RNA sequencing revealed the underlying mechanisms involved in the induction and regulation of HHC treatment following blue light exposure.HHC promoted autophagy by enhancing autophagic flux, reduced oxidative stress and endoplasmic reticulum (ER) stress, and effectively reversed blue light-induced cell death. RNA sequencing-based bioinformatics approaches comprehensively analyze HHC-mediated cellular processes.Our findings elucidate the mechanisms of HHC against blue light damage in RPE cells and are beneficial for the development of natural metabolite-based preventive drugs or functional foods.

Hepatocellular carcinoma (HCC), the most common type of liver cancer, is the leading cause of cancer-related mortality worldwide. Chemotherapy is the major treatment modality for advanced or unresectable HCC; unfortunately, chemoresistance results in a poor prognosis for HCC patients. Exogenous ceramide, a sphingolipid, has been well documented to exert anticancer effects. However, recent reports suggest that sphingolipid metabolism in ceramide-resistant cancer cells favors the conversion of exogenous ceramides to prosurvival sphingolipids, conferring ceramide resistance to cancer cells. However, the mechanism underlying ceramide resistance remains unclear. We previously demonstrated that diTFPP, a novel phenoxyphenol compound, enhances the anti-HCC effect of C

Pancreatic ductal adenocarcinoma (PDAC) is the most lethal cancer, with a dismal 5-year survival rate of less than 10%. It is estimated that approximately 80% of pancreatic ductal carcinoma (PDAC) patients are diagnosed at an advanced or metastatic stage. Hence, most patients are not appropriate candidates for surgical resection and therefore require systemic chemotherapy. However, it has been reported that most patients develop chemoresistance within several months, partly because of antiapoptotic mechanisms. Hence, inducing alternative programmed cell death (PCD), including ferroptosis, necroptosis or pyroptosis, seems to be a promising strategy to overcome antiapoptosis-mediated chemoresistance. In this review, we shed light on the molecular mechanisms of ferroptosis, necroptosis and pyroptosis and suggest several potential strategies (e.g., compounds and nanoparticles [NPs]) that are capable of triggering nonapoptotic PCD to suppress PDAC progression. In conclusion, these strategies might serve as adjuvants in combination with clinical first-line chemotherapies to improve patient survival rates.

Lung cancer is a leading cause of cancer death worldwide, and non-small-cell lung cancer (NSCLC) accounts for 85% of lung cancer, which is highly metastatic, leading to the poor survival rate of patients. We recently reported that 4-[4-(4-hydroxyphenoxy)phenoxy]phenol (4-HPPP), a phenoxyphenol, exerts antihepatoma effects by inducing apoptosis and autophagy. In this study, we further examined the effect of 4-HPPP and its analogs on NSCLC cells. Colony formation assays showed that 4-HPPP exerts selective cytotoxicity against NSCLC H1299 cells; furthermore, the inhibitory effect of 4-HPPP on the proliferation and migration of NSCLC cells was validated using an in vivo zebrafish-based tumor xenograft assay. The flow cytometry-based dichlorofluorescein diacetate (DCF-DA) assays indicated that 4-HPPP caused an increase in reactive oxygen species (ROS) in NSCLC cells, and Western blot assays showed that the major ROS scavenging enzymes superoxide dismutases- (SODs-) 1/2 were upregulated, whereas peroxidase (PRX) was downregulated. Furthermore, 4-HPPP caused both aneuploidization and the accumulation of γH2AX, a sensor of DNA damage, as well as the activation of double-strand break (DSB) markers, especially Ataxia-telangiectasia-mutated and Rad3-related (ATR) in NSCLC cells. Our present work suggests that the antiproliferative effects of 4-HPPP on lung cancer cells could be due to its phenoxyphenol structure, and 4-HPPP could be a candidate molecule for treating NSCLC by modulating ROS levels and lowering the threshold of polyploidy-specific cell death in the future.

VEGF stimulates the formation of new blood vessels by inducing endothelial cell (EC) proliferation and migration. Brefeldin A (BFA)-inhibited guanine nucleotide-exchange protein (BIG)1 and 2 accelerate the replacement of bound GDP with GTP to activate ADP-ribosylation factor (Arf)1, which regulates vesicular transport between the Golgi and plasma membrane. Although it has been reported that treating cells with BFA interferes with Arf1 activation to inhibit VEGF secretion, the role of BIG1 and BIG2 in VEGF trafficking and expression, EC migration and proliferation, and vascular development remains unknown. Here, we found that inactivation of Arf1 reduced VEGF secretion but did not affect the levels of VEGF protein. Interestingly, however, BIG1 and BIG2 knockdown significantly decreased the levels of VEGF mRNA and protein in glioblastoma U251 cells and HUVECs. Furthermore, depletion of BIG1 and BIG2 inhibited HUVEC angiogenesis by diminishing cell migration. Angioblast migration and intersegmental vessel sprouting were also impaired when the BIG2 homolog, Arf guanine nucleotide exchange factor (arfgef)2, was knocked down in zebrafish with endothelial expression of green fluorescent protein (GFP). Depletion of arfgef2 by clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein 9 (Cas9) also caused defects in vascular development of zebrafish embryos. Taken together, these data reveal that BIG1 and BIG2 participate in endothelial cell angiogenesis.-Lu, F.-I., Wang, Y.-T., Wang, Y.-S., Wu, C.-Y., Li, C.-C. Involvement of BIG1 and BIG2 in regulating VEGF expression and angiogenesis.

The predominance for dye-sensitized solar cell (DSSC) is its application in low illumination. However, there are only a few studies to investigate the performance of DSSC under low illumination. In this study, we investigated DSSC's effect on photovoltaic performance under low illumination. The photoelectrode of DSSC is based on titanium dioxide–reduced graphene oxide (RGO)–indium gallium zinc oxide (IGZO) composited photoelectrode, which was fabricated through the hydro-thermal method, spin coating, and sputtering. According to our experiments, the improvement in photovoltaic conversion efficiency of DSSC achieved 69.57%, after introducing IGZO and RGO into the photoelectrode. Moreover, the enhancement of photovoltaic conversion efficiency under low illumination is due to the decrease in dark reaction, and the amount of the current is small under low illumination. Thus, in order to increase the photovoltaic conversion efficiency under low illumination, it is crucial to decrease the back reaction or dark reaction.

Semiconducting polymer dots (Pdots) have recently emerged as a new type of ultrabright fluorescent probe that has been proved to be very useful for biomedical imaging. However, Pdots often suffer from serious fluorescence aggregation-caused quenching (ACQ) especially for near-infrared (NIR) fluorescent Pdots. This article compared two strategies to overcome the ACQ effect in near-infrared emissive Pdot systems: aggregation-induced emission (AIE) and anti-aggregation-caused quenching (anti-ACQ). The results show that the anti-ACQ platform outperforms the AIE system. The fluorescence quantum yield of anti-ACQ-based Pdots can be over 50% and the average per-particle brightness of the Pdots is about 5 times higher than that of the commercially available quantum dots. To help understand why the monomer conformations could greatly affect the optical properties of Pdots, molecular dynamics simulations were performed for the first time in such complicated Pdot systems. To demonstrate applications for in vivo fluorescence imaging, both microangiography imaging on living zebrafish embryos and specific tumor targeting on mice were performed. We anticipate that these studies will pave the way for the design of new highly fluorescent Pdot systems.

The genetic regulation of vascular development is not elucidated completely. We previously characterized the transcription factors Islet2 (Isl2) and Nr2f1b as being critical for vascular growth. In this study, we further performed combinatorial microarrays to identify genes that are potentially regulated by these factors. We verified the changed expression of several targets in isl2/nr2f1b morphants. Those genes expressed in vessels during embryogenesis suggested their functions in vascular development. We selectively assayed a potential target follistatin a (fsta). Follistatin is known to inhibit BMP, and BMP signaling has been shown to be important for angiogenesis. However, the fsta’s role in vascular development has not been well studied. Here, we showed the vascular defects in ISV growth and CVP patterning while overexpressing fsta in the embryo, which mimics the phenotype of isl2/nr2f1b morphants. The vascular abnormalities are likely caused by defects in migration and proliferation. We further observed the altered expression of vessel markers consistent with the vascular defects in (fli:fsta) embryos. We showed that the knockdown of fsta can rescue the vascular defects in (fli:fsta) fish, suggesting the functional specificity of fsta. Moreover, the decreased expression of fsta rescues abnormal vessel growth in isl2 and nr2f1b morphants, indicating that fsta functions downstream of isl2/nr2f1b. Lastly, we showed that Isl2/Nr2f1b control vascular development, via Fsta–BMP signaling in part. Collectively, our microarray data identify many interesting genes regulated by isl2/nr2f1b, which likely function in the vasculature. Our research provides useful information on the genetic control of vascular development.

Members of the Ras superfamily have been found to perform several functions leading to the development of eukaryotes. These small GTPases are divided into five major subfamilies, and their regulators can “turn on” and “turn off” signals. Recent studies have shown that this superfamily of proteins has various roles in the process of vascular development, such as vasculogenesis and angiogenesis. Here, we discuss the role of these subfamilies in the development of the vascular system in zebrafish.

First principles calculation and quasi-harmonic Debye model were used to obtain more physical properties of zirconium carbide under high temperature and high pressure. The results show that the B1 structure of ZrC is energetically more favorable with lower heat of formation than the B2 structure, and that mechanical instability and positive heat of formation induce the inexistence of the B2 structure at normal pressure. It is also found that the B1 structure would transform to the B2 structure under high pressure below the critical point of V/V0=0.570. In addition, various thermodynamic and elastic properties of ZrC are obtained within the temperature range of 0–3000 K and the pressure range of 0–100 GPa. The calculated results not only are discussed and understood in terms of electronic structures, but also agree well with corresponding experimental data in the literature.

Several neurodegenerative diseases are ascribed to disorders caused by the secretion of Cu ions. However, a majority of the current techniques for copper ion detection are restricted to in vivo monitoring and nonspecific interactions. Their methods are limited to the systematic analysis of Cu ions in living organisms. Thus, a synthetic molecular fluorophore, 5-amino 2,3-dihydroquinolinimine (NDQI), has been developed and successfully utilized in in vivo monitoring of the distribution of Cu(II) in zebrafish larvae. The reversible formation of the NDQI-Cu complex allows its use with high metal concentrations and in oxidative stress conditions. The NDQI-directed strategy developed here can quantitatively differentiate cells with different Cu(II) concentrations. Remarkably, dynamic distribution of Cu(II) in the intestine and liver can be observed.

This study monitors the dynamic progress of a newly developed background-free, target responsive strategy; 2,3-dihydroquinolin-4-imine (DQI) that can instantly respond to environmental changes with fluorescence enhancement, revealing a comprehensive platform for in vivo fluorescence bioimaging of mebrane-bound carbonic anhydrase II in HeLa cells and its expression during the growth of larval zebrafish.

In this letter, the indium–gallium–zinc oxide (IGZO) had been applied to the photoelectrode for reducing dark reaction. According to the experimental results, the IGZO film formed an energy barrier to retard the recombination between photo-generated electron in active layer and hole ( $I_{3}^{-}$ ) in electrolyte. It contributes an enhancement of electron lifetime, decrease in dark reaction, and improvement in the short-circuit current density ( $J_{\text {SC}}$ ). Consequently, the photovoltaic conversion efficiency of dye-sensitized solar cell is enhanced from 3.34% to 5.47%. This enhancement has the potential to expand an electron device of photocatalyst.

In this study, titanium dioxide (TiO2) colloid was deposited on the fluorine-doped tin oxide substrate by a spin coating method and blade coating method. The characteristics of indium gallium zinc oxide (IGZO) are uniform porous structure, lower reverse recombination, high optical transparency, and good mobility. Composite of an IGZO/TiO2 film was fabricated by sputtering IGZO on the TiO2 film to form a photoelectrode. The reduced graphene oxide (rGO) has high electrocatalysis activity and excellent electron conduction. Besides, the rGO can be applied to the counter electrode of a dye-sensitized solar cell (DSSC). The IGZO/TiO2 photoelectrode with a platinum (Pt) counter electrode exhibited optimal photovoltaic conversion efficiency ( η ), and η increased 21% compared with a pure TiO2 photoelectrode. η of the IGZO/TiO2 photoelectrode and rGO/Pt counter electrode exhibited optimal efficiency, which was comparable with a TiO2 photoelectrode with the Pt counter electrode under the same condition. In our research, electrochemical impedance spectroscopy was used to analyze the interface resistance between internal components, which could confirm recombination of electrons and electrical conductivity. The rGO/Pt counter electrode demonstrated low resistance between electrolyte and counter electrode, whose resistance was similar to the pure Pt counter electrode.

Under metabolic stress conditions such as hypoxia and glucose deprivation, an increase in the AMP:ATP ratio activates the AMP-activated protein kinase (AMPK) pathway, resulting in the modulation of cellular metabolism. Metformin, which is widely prescribed for type 2 diabetes mellitus (T2DM) patients, regulates blood sugar by inhibiting hepatic gluconeogenesis and promoting insulin sensitivity to facilitate glucose uptake by cells. At the molecular level, the most well-known mechanism of metformin-mediated cytoprotection is AMPK pathway activation, which modulates metabolism and protects cells from degradation or pathogenic changes, such as those related to aging and diabetic retinopathy (DR). Recently, it has been revealed that metformin acts via AMPK- and non-AMPK-mediated pathways to exert effects beyond those related to diabetes treatment that might prevent aging and ameliorate DR. This review focuses on new insights into the anticancer effects of metformin and its potential modulation of several novel types of nonapoptotic cell death, including ferroptosis, pyroptosis, and necroptosis. In addition, the antimetastatic and immunosuppressive effects of metformin and its hypothesized mechanism are also discussed, highlighting promising cancer prevention strategies for the future.

Soft corals-derived natural product, sinularin, was antiproliferative against some cancers but its effect and detailed mechanism on oral cancer cells remain unclear. The subject of this study is to examine the antioral cancer effects and underlying detailed mechanisms in terms of cell viability, oxidative stress, cell cycle analysis, and apoptosis analyses. In MTS assay, sinularin dose-responsively decreased cell viability of three oral cancer cells (Ca9-22, HSC-3, and CAL 27) but only little damage to oral normal cells (HGF-1). This cell killing effect was rescued by the antioxidant N-acetylcysteine (NAC) pretreatment. Abnormal cell morphology and induction of reactive oxygen species (ROS) were found in sinularin-treated oral cancer Ca9-22 cells, however, NAC pretreatment also recovered these changes. Sinularin arrested the Ca9-22 cells at G2/M phase and dysregulated the G2/M regulatory proteins such as cdc2 and cyclin B1. Sinularin dose-responsively induced apoptosis on Ca9-22 cells in terms of flow cytometry (annexin V and pancaspase analyses) and western blotting (caspases 3, 8, 9) and poly (ADP-ribose) polymerase (PARP). These apoptotic changes of sinularin-treated Ca9-22 cells were rescued by NAC pretreatment. Taken together, sinularin induces oxidative stress-mediated antiproliferation, G2/M arrest, and apoptosis against oral cancer cells and may be a potential marine drug for antioral cancer therapy.

Genetic signaling and redox homeostasis are required for proper growth of blood vessels. Here, we report a novel function of peroxiredoxin1 (Prdx1) in vascular development in zebrafish. Knockdown of prdx1 impairs the growth of intersegmental vessel and caudal vein plexus (CVP), and reduces the expression of vascular markers, thus suggesting a role for prdx1 in vasculature and indicating that the antioxidant function of prdx1 is important. We found that H2 O2 -treated embryos also have CVP defects and observed synergistic effects when prdx1 knockdown was combined with H2 O2 treatment. Moreover, N-acetyl-cysteine treatment rescues the vascular defects in prdx1 morphants. These results suggest that oxidative stress disturbs vascularization. Furthermore, we show that the regulation of prdx1 is mediated by Notch and BMP signals.

Ceramide is a sphingolipid which regulates a variety of signaling pathways in eukaryotic cells. Exogenous ceramide has been shown to induce cellular apoptosis. In this study, we observed that exogenous ceramide induced two distinct morphologies of cell fate following C2-ceramide treatment between the two breast cancer cell lines MCF-7 (wild type p53) and MDA-MB-231 (mutant p53) cells. The growth assessment showed that C2-ceramide caused significant growth inhibition and apoptosis in MDA-MB-231 cells through down-regulating the expression of mutant p53 whereas up-regulating the expression of pro-apoptotic Bad, and the proteolytic activation of caspase-3. However, senescence-associated (SA)-β-galactosidase (β-gal) was regulated in MCF-7 cells after C2-ceramide treatment. The results of proliferation and apoptosis assays showed that MCF-7 cells were more resistant to C2-ceramide treatment compared to MDA-MB-231 cells. Furthermore, C2-ceramide treatment induced a time-responsive increase in Rb protein, a key regulator of senescence accompanied with the upregulation of both mRNA level and protein level of SA-genes PAI-1 and TGaseII in MCF-7 but not in MDA-MB-231 cells, suggesting that some cancer cells escape apoptosis through modulating senescence-like phenotype. The results of our present study depicted the mechanism of C2-ceramide-resistant breast cancer cells, which might benefit the strategic development of ceramide-based chemotherapeutics against cancer in the future.

Angioblasts of the developing vascular system require many signaling inputs to initiate their migration, proliferation and differentiation into endothelial cells. What is less studied is which intrinsic cell factors interpret these extrinsic signals. Here, we show the Lim homeodomain transcription factor islet2a (isl2a) is expressed in the lateral posterior mesoderm prior to angioblast migration. isl2a deficient angioblasts show disorganized migration to the midline to form axial vessels and fail to spread around the tailbud of the embryo. Isl2a morphants have fewer vein cells and decreased vein marker expression. We demonstrate that isl2a is required cell autonomously in angioblasts to promote their incorporation into the vein, and is permissive for vein identity. Knockout of isl2a results in decreased migration and proliferation of angioblasts during intersegmental artery growth. Since Notch signaling controls both artery-vein identity and tip-stalk cell formation, we explored the interaction of isl2a and Notch. We find that isl2a expression is negatively regulated by Notch activity, and that isl2a positively regulates flt4, a VEGF-C receptor repressed by Notch during angiogenesis. Thus Isl2a may act as an intermediate between Notch signaling and genetic programs controlling angioblast number and migration, placing it as a novel transcriptional regulator of early angiogenesis.

Wnt/β-catenin signaling controls various cell fates in metazoan development, and its dysregulation is often associated with cancer formation. However, regulations of this signaling pathway are not completely understood. Here, we report that Lzap, a tumor suppressor, controls nuclear translocation of β-catenin. In zebrafish embryos disruption of lzap increases the expression of chordin (chd), which encodes a bone morphogenetic protein (BMP) antagonist that is localized in prospective dorsal cells and promotes dorsal fates. Consistently, lzap-deficient embryos with attenuated BMP signaling are dorsalized, which can be rescued by overexpression of zebrafish lzap or bmp2b or human LZAP. The expansion of chd expression in embryos lacking lzap is due to the accumulation of nuclear β-catenin in ventral cells, in which β-catenin is usually degraded. Furthermore, the activity of GSK3, a master regulator of β-catenin degradation, is suppressed in lzap-deficient embryos via inhibitory phosphorylation. Finally, we also report that a similar regulatory axis is also likely to be present in a human tongue carcinoma cell line, SAS. Our results reveal that Lzap is a novel regulator of GSK3 for the maintenance of ventral cell properties and may prevent carcinogenesis via the regulation of β-catenin degradation.

Lung cancer is a prevalent disease and is one of the leading causes of mortality worldwide. Despite the development of various anticancer drugs, the prognosis of lung cancer is relatively poor. Metastasis of lung cancer, as well as chemoresistance, is associated with a high mortality rate for patients with lung cancer. Camptothecin (CPT) is a well-known anticancer drug, which causes cancer cell apoptosis via the induction of DNA damage; however, the cytotoxicity of CPT easily reaches a plateau at a relatively high dose in lung cancer cells, thus limiting its efficacy. The present study demonstrated that CPT may induce autophagy in two human non‑small cell lung cancer cell lines, H1299 and H460. In addition, the results of a viability assay and Annexin V staining revealed that CPT-induced autophagy could protect lung cancer cells from programmed cell death. Conversely, the cytotoxicity of CPT was increased when autophagy was blocked by 3-methyladenine treatment. Furthermore, inhibition of autophagy enhanced the levels of CPT-induced DNA damage in the lung cancer cell lines. Accordingly, these findings suggested that autophagy exerts a protective role in CPT-treated lung cancer cells, and the combination of CPT with a specific inhibitor of autophagy may be considered a promising strategy for the future treatment of lung cancer.

Ceramides, abundant sphingolipids on the cell membrane, can act as signaling molecules to regulate cellular functions including cell viability. Exogenous ceramide has been shown to exert potent anti-proliferative effects against cancer cells, but little is known about how it affects reactive oxygen species (ROS) in lung cancer cells. In this study, we investigated the effect of N-octanoyl-D-erythro-sphingosine (C8-ceramide) on human non-small-cell lung cancer H1299 cells. Flow cytometry-based assays indicated that C8-ceramide increased the level of endogenous ROS in H1299 cells. Interestingly, the ratio of superoxide dismutases (SODs) SOD1 and SOD2 seem to be regulated by C8-ceramide treatment. Furthermore, the accumulation of cell cycle G1 phase and apoptotic populations in C8-ceramide-treated H1299 cells was observed. The results of the Western blot showed that C8-ceramide causes a dramatically increased protein level of cyclin D1, a critical regulator of cell cycle G1/S transition. These results suggest that C8-ceramide acts as a potent chemotherapeutic agent and may increase the endogenous ROS level by regulating the switch of SOD1 and SOD2, causing the anti-proliferation, and consequently triggering the apoptosis of NSCLC H1299 cells. Accordingly, our works may give a promising strategy for lung cancer treatment in the future.

The dye-sensitized solar cell (DSSC) is a promising device due to indoor application. However, there are fewer literatures to discuss why photovoltaic performances of DSSC can be enhanced under low illumination. In this study, we investigated the photovoltaic performances of DSSC based on titanium dioxide (TiO 2 ) — reduced graphene oxide (RGO) composite photoelectrode under the low illumination. Moreover, the composite of TiO 2 and RGO is synthesized by hydro-thermal method. Besides, the photoelectrode of DSSC is fabricated by a simple process of spin coating. According to experimental results, the photovoltaic conversion efficiency increases slowly during decreases in illumination, but which falls sharply at the lowest illumination. Furthermore, the photovoltaic conversion efficiency is enhanced from 4.01% to 4.91% under low illumanation. According to experimental results, the reason of increase in photovoltaic conversion efficiency of DSSC under low illumination is due to the improvement of electron injection quantum yield. Moreover, the reason of increase in photovoltaic conversion efficiency is clarified.

Several functionalized chromones, the key components of naturally occurring oxygenated heterocycles, have anticancer effects but their sulfone compounds are rarely investigated. In this study, we installed a sulfonyl substituent to chromen-4-one skeleton and synthesized CHW09 to evaluate its antioral cancer effect in terms of cell viability, cell cycle, apoptosis, oxidative stress, and DNA damage. In cell viability assay, CHW09 preferentially kills two oral cancer cells (Ca9-22 and CAL 27), less affecting normal oral cells (HGF-1). Although CHW09 does not change the cell cycle distribution significantly, CHW09 induces apoptosis validated by flow cytometry for annexin V and by western blotting for cleaved poly(ADP-ribose) polymerase (PARP), and caspases 3/8/9. These apoptosis signaling expressions are partly decreased by apoptosis inhibitor (Z-VAD-FMK) or free radical scavenger (N-acetylcysteine). Furthermore, CHW09 induces oxidative stress validated by flow cytometry for the generations of reactive oxygen species (ROS) and mitochondrial superoxide (MitoSOX), and the suppression of mitochondrial membrane potential (MMP). CHW09 also induces DNA damage validated by flow cytometry for the increases of DNA double strand break marker γH2AX and oxidative DNA damage marker 8-oxo-2'-deoxyguanosine (8-oxodG). Therefore, our newly synthesized CHW09 induces apoptosis, oxidative stress, and DNA damage, which may lead to preferential killing of oral cancer cells compared with normal oral cells.

This article describes the design and synthesis of quinoxaline-based semiconducting polymer dots (Pdots) that exhibit near-infrared fluorescence, ultrahigh brightness, large Stokes shifts, and excellent cellular targeting capability. We also introduced fluorine atoms and long alkyl chains into polymer backbones and systematically investigated their effect on the fluorescence quantum yields of Pdots. These new series of quinoxaline-based Pdots have a fluorescence quantum yield as high as 47% with a Stokes shift larger than 150 nm. Single-particle analysis reveals that the average per-particle brightness of the Pdots is at least 6 times higher than that of the commercially available quantum dots. We further demonstrated the use of this new class of quinoxaline-based Pdots for effective and specific cellular and subcellular labeling without any noticeable nonspecific binding. Moreover, the cytotoxicity of Pdots were evaluated on HeLa cells and zebrafish embryos to demonstrate their great biocompatibility. By taking advantage of their extreme brightness and minimal cytotoxicity, we performed, for the first time, in vivo microangiography imaging on living zebrafish embryos using Pdots. These quinoxaline-based NIR-fluorescent Pdots are anticipated to find broad use in a variety of in vitro and in vivo biological research.

Reorganization of the actin cytoskeleton is essential for cell motility and chemotaxis. Actin-binding proteins (ABPs) and membrane lipids, especially phosphoinositides PI(4,5)P2 and PI(3,4,5)P3 are involved in the regulation of this reorganization. At least 15 ABPs have been reported to interact with, or regulated by phosphoinositides (PIPs) whose synthesis is regulated by extracellular signals. Recent studies have uncovered several parallel intracellular signalling pathways that crosstalk in chemotaxing cells. Here, we review the roles of ABPs and phosphoinositides in chemotaxis and cell migration. Linked Articles This article is part of a themed section on Cytoskeleton, Extracellular Matrix, Cell Migration, Wound Healing and Related Topics. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2014.171.issue-24

Vascular development is regulated by complicated signals and molecules in vertebrates. In this study, we characterized a novel function of carboxypeptidase N1 (Cpn1) in the vasculature. We show that cpn1 mRNA is expressed in developing vessels. The knockdown of cpn1 by morpholino injection impairs the growth of intersegmental vessels (ISV) and caudal vein plexus (CVP), suggesting the role of cpn1 in vascular development. We showed that vascular defects are not caused by cell death but are due to the impairment of migration and proliferation. Consistent with vascular growth defects, loss of cpn1 affects the expression of the vascular markers flt4, mrc1, flk, stabilin, and ephrinb2. Furthermore, the overexpression of cpn1 impaired the growth of ISV and CVP, but the remodeling expression of vascular markers was different from the knockdown of cpn1, indicating the differential regulation mechanisms in cpn1-overexpressing embryos. We examine the interaction between cpn1 and multiple signals and observed that cpn1 is regulated by Notch/VEGF signals for ISV growth and likely regulates BMP signals for CVP patterning. In conclusion, we demonstrate that cpn1 has a critical role in the vascular development of zebrafish. We also reveal a fine-tune regulation of cpn1 that controls vascular patterning mediated by multiple signals.

Background 2,9-Bis[2-(pyrrolidin-1-yl)ethoxy]-6-{4-[2-(pyrrolidin-1-yl)ethoxy] phenyl}-11H-indeno[1,2-c]quinoline-11-one (BPIQ), is a synthetic quinoline analog. A previous study showed the anti-cancer potential of BPIQ through modulating mitochondrial-mediated apoptosis. However, the effect of BPIQ on cell migration, an index of cancer metastasis, has not yet been examined. Furthermore, among signal pathways involved in stresses, the members of the mitogen-activated protein kinase (MAPK) family are crucial for regulating the survival and migration of cells. In this study, the aim was to explore further the role of MAPK members, including JNK, p38 and extracellular signal-regulated kinase (ERK) in BPIQ-induced apoptosis and anti-migration of human non-small cell lung cancer (NSCLC) cells. Methods Western Blot assay was performed for detecting the activation of MAPK members in NSCLC H1299 cells following BPIQ administration. Cellular proliferation was determined using a trypan blue exclusion assay. Cellular apoptosis was detected using flow cytometer-based Annexin V/propidium iodide dual staining. Cellular migration was determined using wound-healing assay and Boyden’s chamber assay. Zymography assay was performed for examining MMP-2 and -9 activities. The assessment of MAPK inhibition was performed for further validating the role of JNK, p38, and ERK in BPIQ-induced growth inhibition, apoptosis, and migration of NSCLC cells. Results Western Blot assay showed that BPIQ treatment upregulates the phosphorylated levels of both MAPK proteins JNK and ERK. However, only ERK inhibitor rescues BPIQ-induced growth inhibition of NSCLC H1299 cells. The results of Annexin V assay further confirmed the pro-apoptotic role of ERK in BPIQ-induced cell death of H1299 cells. The results of wound healing and Boyden chamber assays showed that sub-IC50 (sub-lethal) concentrations of BPIQ cause a significant inhibition of migration in H1299 cells accompanied with downregulating the activity of MMP-2 and -9, the motility index of cancer cells. Inhibition of ERK significantly enhances BPIQ-induced anti-migration of H1299 cells. Conclusions Our results suggest ERK may play dual roles in BPIQ-induced apoptosis and anti-migration, and it would be worthwhile further developing strategies for treating chemoresistant lung cancers through modulating ERK activity. Electronic supplementary material The online version of this article (doi:10.1186/s12935-017-0403-0) contains supplementary material, which is available to authorized users.

Background Gene therapy of proopiomelanocortin, the precursor of α-melanocyte-stimulating hormone (α-MSH), suppresses the neovascularization in tumors. However, the roles of α-MSH in angiogenesis remain unclear. Methods The influence of α-MSH on angiogenesis was evaluated by ex vivo rat aorta and in vivo, including transgenic zebrafish and chicken chorioallantoic membrane (CAM) assays. The effect of α-MSH on proliferation, matrix metalloproteinase (MMP) secretion, migration and tube formation was examined using human umbilical vein endothelial cells (HUVECs). The expression of vascular endothelial growth factor (VEGF) and VEGF receptor 2 (VEGFR2) was investigated by quantitative RT-PCR, immunoblot and immunofluorescent analysis. Antibodies' neutralization was employed to dissect the receptor(s) transmitting α-MSH signaling. Results Application of α-MSH potently suppressed the microvessels sprouting in organotypic aortic rings. Besides, α-MSH perturbed the vessels development in zebrafish and chicken embryos. α-MSH (0.01–10 nM) inhibited the MMP-2 secretion, migration and tube formation of HUVECs without affecting proliferation. Mechanistic studies unveiled α-MSH decreased the VEGF expression and release in HUVECs. Besides, α-MSH downregulated the VEGFR2 expression at transcriptional and translational levels. Importantly, α-MSH attenuated the Akt phosphorylation, but enhanced the expression of PTEN, endogenous antagonist of PI3K/Akt signaling. Expression analysis and antibody neutralization revealed that MC1-R and MC2-R participated in α-MSH-induced blockage of migration and VEGF/VEGFR2/Akt signaling. However, VEGF supply failed to reverse the anti-angiogenic function of α-MSH. Conclusions α-MSH inhibits the physiological angiogenesis by attenuating VEGF/VEGFR2/Akt signaling in endothelial cells. General significance α-MSH is a potent angiogenesis inhibitor targeting at endothelial VEGF/VEGFR2 signaling, which may have potential for therapeutic application.

Soft corals-derived natural product, sinularin, was antiproliferative against some cancers but its effect and detailed mechanism on oral cancer cells remain unclear. The subject of this study is to examine the antioral cancer effects and underlying detailed mechanisms in terms of cell viability, oxidative stress, cell cycle analysis, and apoptosis analyses. In MTS assay, sinularin dose-responsively decreased cell viability of three oral cancer cells (Ca9-22, HSC-3, and CAL 27) but only little damage to oral normal cells (HGF-1). This cell killing effect was rescued by the antioxidant N-acetylcysteine (NAC) pretreatment. Abnormal cell morphology and induction of reactive oxygen species (ROS) were found in sinularin-treated oral cancer Ca9-22 cells, however, NAC pretreatment also recovered these changes. Sinularin arrested the Ca9-22 cells at G2/M phase and dysregulated the G2/M regulatory proteins such as cdc2 and cyclin B1. Sinularin dose-responsively induced apoptosis on Ca9-22 cells in terms of flow cytometry (annexin V and pancaspase analyses) and western blotting (caspases 3, 8, 9) and poly (ADP-ribose) polymerase (PARP). These apoptotic changes of sinularin-treated Ca9-22 cells were rescued by NAC pretreatment. Taken together, sinularin induces oxidative stress-mediated antiproliferation, G2/M arrest, and apoptosis against oral cancer cells and may be a potential marine drug for antioral cancer therapy.

Trans-ferulic (FA) acid exhibits antioxidant effects in vitro. However, the underlying mechanism of trans-FA activity in cellular physiology, especially cancer physiology, remains largely unknown. This study investigated the cellular physiological effects of trans-FA on the H1299 human lung cancer cell line. The 2,2-diphenyl-1-picrylhydrazyl assay was used to determine free radical scavenging capability. Assessment of intracellular reactive oxygen species (ROS) was evaluated using oxidized 2ʹ,7ʹ-dichlorofluorescin diacetate and dihydroethidium staining. Trypan blue exclusion, colony formation, and anchorage-independent growth assays were used to determine cellular proliferation. Annexin V staining assay was used to assess cellular apoptosis by flow cytometry. Wound healing and Boyden’s well assays were used to detect the migration and invasion of cells. Gelatin zymography was used to detect matrix metalloproteinase (MMP-2 and MMP-9) activity. Western blotting was used to detect expression levels of various signaling pathway proteins. DPPH assay results indicated that trans-FA exerted potent antioxidant effects. However, trans-FA increased intracellular ROS levels, including hydrogen peroxide and superoxide anion, in H1299 cells. Trans-FA treatment inhibited cellular proliferation and induced moderate apoptotic cell death at the highest concentration used (0.6 mM). Furthermore, trans-FA moderately inhibited the migration of H1299 cells at the concentrations of 0.3 and 0.6 mM and attenuated MMP-2 and MMP-9 activity. Trans-FA caused the phosphorylation of β-catenin, resulting in proteasomal degradation of β-catenin. Conversely, trans-FA treatment increased the expression of pro-apoptotic factor Bax and decreased the expression of pro-survival factor survivin. Various concentrations (0.06–0.6 mM) of trans-FA exert both anti-proliferation and anti-migration effects in the human lung cancer cell line H1299.

&alpha, melanocyte-stimulating hormone (&alpha, MSH) has been characterized as a novel angiogenesis inhibitor. The homeostasis of nitric oxide (NO) plays an important role in neovascularization. However, it remains unclear whether &alpha, MSH mitigates angiogenesis through modulation of NO and its signaling pathway. The present study elucidated the function and mechanism of NO signaling in &alpha, MSH-induced angiogenesis inhibition using cultured human umbilical vein endothelial cells (HUVECs), rat aorta rings, and transgenic zebrafish. By Griess reagent assay, it was found &alpha, MSH dose-dependently reduced the NO release in HUVECs. Immunoblotting and immunofluorescence analysis revealed &alpha, MSH potently suppressed endothelial and inducible nitric oxide synthase (eNOS/iNOS) expression, which was accompanied with inhibition of nuclear factor kappa B (NF-&kappa, B) activities. Excessive supply of NO donor l-arginine reversed the &alpha, MSH-induced angiogenesis inhibition in vitro and in vivo. By using antibody neutralization and RNA interference, it was delineated that melanocortin-1 receptor (MC1-R) and melanocortin-2 receptor (MC2-R) participated in &alpha, MSH-induced inhibition of NO production and NF-&kappa, B/eNOS/iNOS signaling. This was supported by pharmaceutical inhibition of protein kinase A (PKA), the downstream effector of MC-Rs signaling, using H89 abolished the &alpha, MSH-mediated suppression of NO release and eNOS/iNOS protein level. Therefore, &alpha, MSH exerts anti-angiogenic function by perturbing NO bioavailability and eNOS/iNOS expression in endothelial cells.

Paclobutrazol (PBZ) is a widely used fungicide that shows toxicity to aquatic embryos, probably through rain-wash. Here, we specifically focus on its toxic effect on eye development in zebrafish, as well as the role of retinoic acid (RA), a metabolite of vitamin A that controls proliferation and differentiation of retinal photoreceptor cells, in this toxicity. Embryos were exposed to PBZ with or without RA from 2 to 72 h post-fertilization (hpf), and PBZ-treated embryos (2–72 hpf) were exposed to RA for additional hours until 120 hpf. Eye size and histology were examined. Expression levels of gnat1 (rod photoreceptor marker), gnat2 (cone photoreceptor marker), aldehyde dehydrogenases (encoding key enzymes for RA synthesis), and phospho-histone H3 (an M-phase marker) in the eyes of control and treated embryos were examined. PBZ exposure dramatically reduces photoreceptor proliferation, thus resulting in a thinning of the photoreceptor cell layer and leading to a small eye. Co-treatment of PBZ with RA, or post-treatment of PBZ-treated embryos with RA, partially rescues photoreceptor cells, revealed by expression levels of marker proteins and by retinal cell proliferation. PBZ has strong embryonic toxicity to retinal photoreceptors, probably via suppressing the production of RA, with effects including impaired retinal cell division.

In recent years, combination chemotherapy is a primary strategy for treating lung cancer; however, the issues of antagonism and side effects still limit its applications. The development of chemosensitizer aims to sensitize chemoresistant cancer cells to anticancer drugs and therefore improve the efficacy of chemotherapy. In this study, we examined whether N-[2-(morpholin-4-yl)phenyl]-2-{8-oxatricyclo[7.4.0.0,2,7]trideca-1(9),2(7),3,5,10,12-hexaen-4-yloxy}acetamide (NPOA), an acetamide derivative, sensitizes human non-small-cell lung cancer (NSCLC) H1299 cells towards camptothecin- (CPT-) induced apoptosis effects. Our results demonstrate that the combination of CPT and NPOA enhances anti-lung-cancer effect. The cytometer-based Annexin V/propidium iodide (PI) staining showed that CPT and NPOA cotreatment causes an increased population of apoptotic cells compared to CPT treatment alone. Moreover, Western blotting assay showed an enhancement of Bax expression and caspase cascade leading to cell death of H1299 cells. Besides, CPT and NPOA cotreatment-mediated disruption of mitochondrial membrane potential (MMP) in H1299 cells may function through increasing the activation of the stressed-associated c-Jun N-terminal kinase (JNK). These results showed that NPOA treatment sensitizes H1299 cells towards CPT-induced accumulation of cell cycle S phase and mitochondrial-mediated apoptosis through regulating endogenous ROS and JNK activation. Accordingly, NPOA could be a candidate chemosensitizer of CPT derivative agents such as irinotecan or topotecan in the future.

The natural compound camptothecin (CPT) derivatives have widely been used for anti-cancer treatments, including lung cancer. However, many chemoresistant cancer cells often develop a relatively higher threshold for inducing apoptosis, causing a limited efficacy of anti-cancer drugs. Likewise, lung cancer cells acquire chemoresistance against CPT analogs, such as irinotecan and topotecan, finally resulting in an unsatisfied outcome and poor prognosis of lung cancer patients. TFPP is a quinone-containing compound as a candidate for CPT-based combination chemotherapy. In this study, we examined the effect of TFPP and CPT cotreatment on non-small cell lung cancer (NSCLC) cells. Cell proliferation and flow cytometry-based Annexin-V/PI staining assays demonstrated the synergistic effect of TFPP on CPT-induced apoptosis in both NSCLC A549 and H1299 cells. The results of CPT and TFPP cotreatment cause the regulation of the ERK-Bim axis and the activation of mitochondrial-mediated caspase cascade, including caspase-9 and caspase-3. Besides, TFPP significantly enhanced CPT-induced endogenous reactive oxygen species (ROS) in the two NSCLC cells. In contrast, the treatment of N-acetyl-L-cysteine (NAC), an ROS scavenger, rescues the apoptosis of NSCLC cells induced by TFPP and CPT cotreatment, suggesting that the synergistic effect of TFPP on CPT-induced anti-NSCLC cells is through upregulating ROS production. Consequently, our results suggest that TFPP sensitizes NSCLC towards CPT-based chemotherapy may act through decreasing the apoptosis-initiating threshold. Therefore, TFPP may be a promising chemosensitizer for lung cancer treatment, and the underlying mechanism warrants further.

Ascaris lumbricoides and Ascaris suum are parasitic nematodes living in the small intestine of humans and pigs, and can cause the disease ascariasis. For long, there has been controversy as to whether the two ascaridoid taxa represent the same species due to their significant resemblances in morphology. However, the complete mitochondrial (mt) genome data have been lacking for A. lumbricoides in spite of human and animal health significance and socio-economic impact globally of these parasites. In the present study, we sequenced the complete mt genomes of A. lumbricoides and A. suum (China isolate), which was 14,303 bp and 14,311 bp in size, respectively. The identity of the mt genomes was 98.1% between A. lumbricoides and A. suum (China isolate), and 98.5% between A. suum (China isolate) and A. suum (USA isolate). Both genomes are circular, and consist of 36 genes, including 12 genes for proteins, 2 genes for rRNA and 22 genes for tRNA, which are consistent with that of all other species of ascaridoid studied to date. All genes are transcribed in the same direction and have a nucleotide composition high in A and T (71.7% for A. lumbricoides and 71.8% for A. suum). The AT bias had a significant effect on both the codon usage pattern and amino acid composition of proteins. Phylogenetic analyses of A. lumbricoides and A. suum using concatenated amino acid sequences of 12 protein-coding genes, with three different computational algorithms (Bayesian analysis, maximum likelihood and maximum parsimony) all clustered in a clade with high statistical support, indicating that A. lumbricoides and A. suum was very closely related. These mt genome data and the results provide some additional genetic evidence that A. lumbricoides and A. suum may represent the same species. The mt genome data presented in this study are also useful novel markers for studying the molecular epidemiology and population genetics of Ascaris.

Little is known about how metalloproteins in the secretory pathway obtain their metal ion cofactors. We used the Pho8 alkaline phosphatase of the yeast Saccharomyces cerevisiae to probe this process in vivo. We found that both Pho8 activity and protein accumulation are zinc-dependent and decrease in zinc-limited cells. Low Pho8 accumulation was the result of degradation by vacuolar proteases. Surprisingly, the protective effect of zinc on Pho8 stability was not solely due to Zn(2+) binding to the active-site ligands suggesting that the Pho8 protein is targeted for degradation in zinc-limited cells by another mechanism. Pho8 appears to be a rare example of a metalloprotein whose stability is regulated by its metal cofactor independently of active-site binding. We also assessed which zinc transporters are responsible for supplying zinc to Pho8. We found that the Zrc1 and Cot1 vacuolar zinc transporters play the major role while the Msc2/Zrg17 zinc transporter complex active in the endoplasmic reticulum is not involved. These results demonstrate that the vacuolar zinc transporters, previously implicated in metal detoxification, also deliver zinc to certain metalloproteins within intracellular compartments. These data suggest that Pho8 receives its metal cofactor in the vacuole rather than in earlier compartments of the secretory pathway.

Vascular development is important for vertebrates and regulated by regulators via complicated signaling pathways. In our previous study, transcription factor islet2 regulated vein and ISV formation mediated by notch signaling. Genome-wide transcriptional analysis showed that cpn1 is regulated by islet2/coupTFIb, suggested its function in vasculature. However, no direct evidence shown the role of Cpn1 in vascular function so far. Thus, we hypothesize that cpn1 encode enzymatic active subunits to perform CPN activity and function in vascular development. In-situ hybridization showed cpn1 is expressed in developing vessels. Overexpression of cpn1 impairs the growth of ISV (intersegmental vessel) and CVP (cardinal vein plexus), which is similar to the phenotype of isl2 morphant. Knockdown of cpn1 by morpholino injection also causes vascular defects, suggesting the role of cpn1 in controlling ISV and CVP growth. We further showed the cpn1 MO knockdown works efficiently by probing cpn1 expression products and k...

Genetic signaling and redox homeostasis are required for proper growth of blood vessels. Using zebrafish as a model organism have been intensively identified many molecules that control vasculature...

Background Trans-ferulic (FA) acid exhibits antioxidant effects in vitro. However, the underlying mechanism of trans-FA activity in cellular physiology, especially cancer physiology, remains largely unknown. This study investigated the cellular physiological effects of trans-FA on the H1299 human lung cancer cell line. Methods The 2,2-diphenyl-1-picrylhydrazyl assay was used to determine free radical scavenging capability. Assessment of intracellular reactive oxygen species (ROS) was evaluated using oxidized 2ʹ,7ʹ-dichlorofluorescin diacetate and dihydroethidium staining. Trypan blue exclusion, colony formation, and anchorage-independent growth assays were used to determine cellular proliferation. Annexin V staining assay was used to assess cellular apoptosis by flow cytometry. Wound healing and Boyden’s well assays were used to detect the migration and invasion of cells. Gelatin zymography was used to detect matrix metalloproteinase (MMP-2 and MMP-9) activity. Western blotting was used to detect expression levels of various signaling pathway proteins. Results DPPH assay results indicated that trans-FA exerted potent antioxidant effects. However, trans-FA increased intracellular ROS levels, including hydrogen peroxide and superoxide anion, in H1299 cells. Trans-FA treatment inhibited cellular proliferation and induced moderate apoptotic cell death at the highest concentration used (0.6 mM). Furthermore, trans-FA moderately inhibited the migration of H1299 cells at the concentrations of 0.3 and 0.6 mM and attenuated MMP-2 and MMP-9 activity. Trans-FA caused the phosphorylation of β-catenin, resulting in proteasomal degradation of β-catenin. Conversely, trans-FA treatment increased the expression of pro-apoptotic factor Bax and decreased the expression of pro-survival factor survivin. Conclusion Various concentrations (0.06–0.6 mM) of trans-FA exert both anti-proliferation and anti-migration effects in the human lung cancer cell line H1299. Electronic supplementary material The online version of this article (doi:10.1186/s13020-016-0116-7) contains supplementary material, which is available to authorized users.

The Zap1 transcription factor is a central player in zinc homeostasis in yeast. This protein regulates the expression of genes involved in zinc accumulation and storage. For most of its target genes, Zap1 activates expression in zinc-limited cells and this function is inhibited in replete cells. Zap1 has two activation domains, AD1 and AD2, which are independently regulated by zinc status. In this study, we characterized AD1 and its regulation by zinc. AD1 was mapped using deletions to residues 332-402 of Zap1. The region required for the zinc responsiveness of this activation domain, designated 'ZRD(AD1), was mapped to residues 182-502. Thus, AD1 is embedded within its larger zinc-responsive domain. Using a combination of in silico analysis, random mutagenesis and site-directed mutagenesis, we identified key residues within ZRD(AD1) required for its regulation by zinc. Most of these residues are cysteines and histidines that could potentially serve as Zn(II) ligands. These results suggest that ZRD(AD1) senses zinc by direct Zn(II) binding. Consistent with this hypothesis, purified ZRD(AD1) bound multiple Zn(II) ions. Finally, our results indicate that, in the context of the full-length Zap1 protein, AD1 and AD2 are both critical to the full control of gene expression in response to zinc.