HeLa Cell Death Research Articles

Raloxifene-loaded and aptamer-bonded exosomes induce autophagic and apoptotic death in HeLa cells by enhancing the lysosomotropic effect

<b>Background:</b> Raloxifene, a selective estrogen receptor modulator, is also known to be a lysosomotropic agent. The bioavailability of raloxifene is around 2% due to extensive hepatic transport. Exosomes are nanosized vesicles that are naturally released from cells. <b>Method:</b> In this study, exosomes released from HeLa cervical cancer cells were loaded with raloxifene to increase its bioavailability, and an aptamer was attached to the exosome membrane for targeting only HeLa cells. Characterization of exosomes isolated from HeLa cells was performed by transmission electron microscopy, zeta sizer, and western blotting. In addition, the cytotoxic, apoptotic, autophagic, and lysosomotropic effects of the prepared Exo-Apt-Ral formulation on HeLa cervical cancer cells were investigated. <b>Results:</b> According to zeta analysis, the sizes of the empty exosome and Exo-Apt-Ral formulation were measured as 66 ± 12 and 120 ± 21 nm, respectively. There was a rise in the lysosomal permeability of HeLa cells after the Exo-Apt-Ral application. In addition, both apoptotic and autophagic death mechanisms were triggered in HeLa cells after the Exo-Apt-Ral application. <b>Conclusion:</b> This study showed that raloxifene functionalized by loading into aptamer-bound exosomes can be a new targeted drug carrier system for cervical cancer.

Multifunctional DNA nanoprobe for tumor-targeted synergistic therapy by integrating chemodynamic therapy with gene silencing.

Due to the high complexity, diversity and heterogeneity of tumor occurrence and development, multi-mode synergistic therapy is more effective than single treatment modes to improve the antitumor efficacy. Also, multifunctional probes are crucial to realize synergistic therapy. Herein, a multifunctional DNA tetrahedron nanoprobe was ingeniously designed to simultaneously achieve chemodynamic therapy (CDT) and gene silencing for synergistic antitumor. The multifunctional DNA tetrahedron nanoprobe, DNA tetrahedron-silver nanocluster-antagomir-21 (D-sgc8-DTNS-AgNCs-Anta-21), integrated a CDT reagent (DNA-AgNCs) and miRNA-21 inhibitor (Anta-21) with a specific recognition probe (aptamer). After targeted entry in cancer cells, D-sgc8-DTNS-AgNCs-Anta-21 silenced endogenous miRNA-21 by Anta-21 and produced highly toxic ˙OH by reacting with H2O2, which induced apoptosis in the tumor cells. The targeted recognition of aptamers led to the concentration-dependent death of HeLa cells. On the contrary, the cell survival rate of normal cells was basically unaffected with an increase in the concentration of D-sgc8-DTNS-AgNCs-Anta-21. Therefore, the diverse functions, biocompatibility and programmability of DNA provide a useful and easy way to assemble multifunctional probes for synergistic therapy.

Optimized extraction of sulfated polysaccharide from brown seaweed Sargassum polycystum and its evaluation for anti-cancer and wound healing potential

• Optimized acidic hot water extraction of WSCSPs. • WSCSPs exhibit antioxidant property. • WSCSPs promote wound healing in RAW 264.7 cells. • WSCSPs is not cytotoxic to normal L6 myoblast cells. • WSCSPs induce death of HeLa cancer cells. In the present study, we optimized the extraction of water-soluble crude sulfated polysaccharide (WSCSP) from Sargassum polycystum and its biological activity was investigated. The WSCSP was extracted from S. polycystum by the acidic water extraction method. The Box-Behnken experimental design was used as a tool for the extraction and evaluated in variable conditions extraction temperature as 60 °C, extraction time duration as 60 min, pH 5.0 and acid hot water: algal ratio 1:50 (g/ml) on these conditions, respectively. The use of acid hot water extraction was efficient to obtain a high WSCSP yield (59.80 ± 2.52%) and further characterization and morphology were analyzed by Fourier-transform infrared spectroscopy (FTIR), Nuclear magnetic resonance spectroscopy (NMR), Thermogravimetry analysis (TGA), X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and the dynamic light scattering (DLS). WSCSP was shown to possess antioxidant activity, as evident by the DPPH assay. Moreover, WSCSP did not induce any significant cytotoxicity in L6 myoblast normal cell line. WSCSP also triggers wound healing in RAW 264.7 cells. WSCSP also induces significant death of HeLa (cervical cancer) cells, marking its cancer specificity. Hence WSCSP derived from Sargassum polycystum can be used as an anticancer candidate in future.

Cytotoxicity Assessment of Sea Star Asterias Rubens Protein-Sip-Young-6 HIS in Hela Cells. Comparisons with Doxorubicine Action

The objective of this work is to assess whether recombinant protein SIP-Young-6 HIS, produced in HEK293, induces cell death in HeLa cells, when compared to doxorubicine action to achieve this, the metabolic activity is measured with the Cell Cytotoxicity Assay Kit (Abnova, Ref# KA4151) which contains a water-soluble dye that changes its absorption spectra upon cellular reduction. It seems that a post-translational modification occurs in HEK 293 since obtained results with the sea star young protein were less convincing than the preliminary ones. These last used directly the sea star IGKappa gene cloned in a CMV vector.

Mixed Ligand Mononuclear Copper(II) Complex as a Promising Anticancer Agent: Interaction Studies with DNA/HSA, Molecular Docking, and In Vitro Cytotoxicity Studies.

The isolated copper(II) complex [CuL(o-phen)]·H2O (1) [H2L = o-HO-C6H4C(H)=N-C6H4-SH-o, o-phen = 1,10-phenanthroline] was structurally characterized using single-crystal X-ray crystallography. 1 in CH3CN at liquid nitrogen temperature displayed a characteristic monomeric X-band electron paramagnetic resonance spectrum having a tetragonal character with g∥ = 2.1479 and g⊥ = 2.0691 and A∥ ≈ 18.0 mT and A⊥ ≤ 3.9 mT, respectively. 1 showed a strong binding affinity toward calf thymus DNA as reflected from its intrinsic binding constant (Kb = 7.88 × 105 M–1), and its competitive displacement of ethidium bromide suggested an intercalative DNA-binding mode (Kapp = 1.32 × 106 M–1). This was confirmed from the viscosity study that showed an increase in the viscosity of DNA with an increasing concentration of 1. Complex 1 is highly efficient in promoting oxidative and hydrolytic DNA cleavage (kobs = 1.987 h–1). 1 showed a strong binding affinity with the carrier protein human serum albumin (HSA) (Ka = 5.22 × 105 M–1). A high bimolecular quenching constant kq = 2.29 × 1013 M–1s–1 indicated a static quenching mechanism involved in the fluorescence quenching of HSA by 1. Fluorescence resonance energy transfer theory suggested that the distance (r = 3.52 nm) between 1 and HSA is very close. Molecular docking studies suggested that 1 primarily binds to HSA in subdomain IIA. A protein–ligand interaction profiler was used to visualize hydrophobic, hydrogen bonds, and π–cation interactions between HSA and 1. A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay using HeLa and MDA-MB-231 cells showed a significant in vitro anticancer activity of 1 (IC50 2.63 and 2.68 μM, respectively). Nuclear staining assays suggested apoptotic cell death in HeLa cells treated with 1. The effect of 1 on the cytoskeletal actin filaments visualized using phalloidin staining showed extensive destruction of actin filaments. Flow cytometric analysis indicated that 1 inhibits the growth of HeLa cells through cell cycle arrest in the S phase. Western blot analysis showed upregulation in the expression of apoptotic marker proteins caspase 3, p53, and Bax. These results collectively indicate that 1 induces apoptosis by promoting DNA damage and has a high potential to act as an anticancer agent.

Modulation of Local Cellular Activities using a Photothermal Dye-Based Subcellular-Sized Heat Spot.

Thermal engineering at the microscale, such as the regulation and precise evaluation of the temperature within cellular environments, is a major challenge for basic biological research and biomaterials development. We engineered a polymeric nanoparticle having a fluorescent temperature sensory dye and a photothermal dye embedded in the polymer matrix, named nanoheater-thermometer (nanoHT). When nanoHT is illuminated with a near-infrared laser at 808 nm, a subcellular-sized heat spot is generated in a live cell. Fluorescence thermometry allows the temperature increment to be read out concurrently at individual heat spots. Within a few seconds of an increase in temperature by approximately 11.4 °C from the base temperature (37 °C), we observed the death of HeLa cells. The cell death was observed to be triggered from the exact local heat spot at the subcellular level under the fluorescence microscope. Furthermore, we demonstrate the application of nanoHT for the induction of muscle contraction in C2C12 myotubes by heat release. We successfully showed heat-induced contraction to occur in a limited area of a single myotube based on the alteration of protein–protein interactions related to the contraction event. These results demonstrate that even a single heat spot provided by a photothermal material can be extremely effective in altering cellular functions.

Cisplatin and paclitaxel-loaded liposomes induced cervical cancer (HeLa) cell death with multiple copies of human papillomavirus by apoptosis and decreased their cytotoxic effect on non-tumor cells

In the research and development of new anticancer treatments, nanotechnology is a powerful tool in the fight against cancer. Considering that cancer is a global health problem, we co-encapsulated cisplatin (CP) and paclitaxel (PTX) in liposomes and evaluated their cytotoxicity in fibroblasts (NIH3T3) and HeLa cells containing multiple copies of human papillomavirus 18 (HeLa-HPV18). CP and PTX were successfully encapsulated into liposomes with a particle size distribution <180 nm, poly dispersion index (PDI) < 0.2, spherical morphology, high negative zeta potential, and encapsulation efficiency of 59% (CP), 88% (PTX) and 57% + 87% (CP + PTX). FTIR suggests that the drugs were successfully encapsulated in liposomes. The liposomes ensured a higher cytotoxic effect on HeLa-HPV18 cells and a smaller cytotoxic effect on NIH3T3 cells when the drugs were encapsulated. In addition, combined treatment with CP and PTX encapsulated in liposomes ensured a synergic effect between the drugs, inducing cell death by apoptosis.

Aloe-Emodin Induces Mitochondrial Dysfunction and Pyroptosis by Activation of the Caspase-9/3/Gasdermin E Axis in HeLa Cells

Aloe-emodin (1,8-dihydroxy-3-hydroxymethyl-anthraquinone), derived from some Chinese edible medicinal herbs, exerts a potential anticancer activity on various cancer cells, making it a drug candidate for cancer therapy. Yet, the role of aloe-emodin in pyroptosis, a new type of cell death, is uncharacterized. In this study, we explored the molecular mechanisms of aloe-emodin-triggered pyroptosis. Aloe-emodin inhibited proliferation and migration and triggered caspase-dependent cell death of HeLa cells in a dose-dependent manner. Aloe-emodin caused mitochondrial dysfunction and induced pyroptosis by activating the caspase-9/3/GSDME axis. Transcriptional analysis showed extensive changes in gene expressions in cellular pathways, including MAPK, p53, and PI3K-Akt pathways when treated with aloe-emodin. This study not only identified a novel role of aloe-emodin in pyroptotic cell death, but also performed a systematical genome-wide analysis of cellular pathways responding to aloe-emodin, providing a theoretical basis for applying anthraquinone derivatives in the treatment of GSDME-expressing cancers.

The Effect of Gambier Catechin Isolate on Cervical Cancer Cell Death (HeLa Cell Lines)

BACKGROUND: Cervical cancer is the second most common type of cancer in women worldwide. Human Papilloma Virus infection on the surface of the cervix is the most common cause which can cause abnormal growth of cervical cells.&#x0D; AIM: This research was conducted in vitro which aims to determine whether catechin compounds can inhibit the growth and regulation of cervical cancer cells (HeLa cell line).&#x0D; METHODS: This is experimental research using the colourimetric assay method and qualitative observation of cervical cancer cell morphology (HeLa cell line) under a fluorescence microscope. The administration of catechin compounds was tested at different concentrations to HeLa cells, namely 1000 g/ml, 500 g/ml, 250 g/ml, 125 g/ml, 62.5 g/ml, 31.25 g/ml.&#x0D; RESULTS: The smallest cell viability was obtained from a concentration of 1000 g/ml which was 5.98% while the largest cell viability was found at a concentration of 31.25 g/ml, which was 40.01%. The resulting IC50 value was 22.91 g/ml. Gambier catechin compounds have very high antioxidants because they contain an IC50 value &lt; 50 g/ml. The effect of gambier catechin compounds on HeLa cell death can be found by increasing the percentage of dead cells. The difference in the fluorescence images of HeLa cells in the experimental group was assessed based on the percentage of the number of cells that died or underwent apoptosis, which was marked by a red or orange fluorescent image. At the concentration of IC25, 31.87% of dead cells were found, the concentration of IC50 was 51.09% of dead cells, and the concentration of IC75 was 82.51% of dead cells. The test results showed that there was a significant difference in the average percentage of cells undergoing apoptosis in all study groups with p &lt;0.05.&#x0D; CONCLUSION: Based on research, it can be concluded that catechin compounds could inhibit the growth and regulation of cervical cancer cells (HeLa cell line). Later, it has the potential to be developed as an anticancer candidate for cervical cancer.&#x0D; Keyword: Cervical cancer, Catechin, Apoptosis, HeLa cell line, Cell death.

NAMPT-dependent NAD+ salvage is crucial for the decision between apoptotic and necrotic cell death under oxidative stress

Oxidative stress is a state in which the accumulation of reactive oxygen species exceeds the capacity of cellular antioxidant systems. Both apoptosis and necrosis are observed under oxidative stress, and we have reported that these two forms of cell death are induced in H2O2-stimulated HeLa cells depending on the concentration of H2O2. Weak H2O2 stimulation induces apoptosis, while strong H2O2 stimulation induces necrosis. However, the detailed mechanisms controlling the switching between these forms of cell death depending on the level of oxidative stress remain elusive. Here, we found that NAD+ metabolism is a key factor in determining the form of cell death in H2O2-stimulated HeLa cells. Under both weak and strong H2O2 stimulation, intracellular nicotinamide adenine dinucleotide (NAD+) was depleted to a similar extent by poly (ADP-ribose) (PAR) polymerase 1 (PARP1)-dependent consumption. However, the intracellular NAD+ concentration recovered under weak H2O2 stimulation but not under strong H2O2 stimulation. NAD+ recovery was mediated by nicotinamide (NAM) phosphoribosyltransferase (NAMPT)-dependent synthesis via the NAD+ salvage pathway, which was suggested to be impaired only under strong H2O2 stimulation. Furthermore, downstream of NAD+, the dynamics of the intracellular ATP concentration paralleled those of NAD+, and ATP-dependent caspase-9 activation via apoptosome formation was thus impaired under strong H2O2 stimulation. Collectively, these findings suggest that NAD+ dynamics balanced by PARP1-dependent consumption and NAMPT-dependent production are important to determine the form of cell death activated under oxidative stress.

Fenofibrate Exerts Anticancer Effects on Human Cervical Cancer HeLa Cells via Caspase-Dependent Apoptosis and Cell Cycle Arrest

Objective: In the present study, we attempted to identify the effects of fenofibrate on human cervical cancer cells. Methods: The cytotoxicity of fenofibrate in cervical cancer cells was determined by Cell Counting Kit-8. Immunoblotting assay was used to determine the protein expression of caspase-3, poly ADP-ribose polymerase cleavage, B-cell lymphoma 2 family protein expression, microtubule-associated protein 1A/1B-light chain 3 (LC3), as well as cyclins and cyclin-dependent kinases. Immunofluorescence imaging was used to determine the expression of cleaved caspase-3 and LC3. Flow cytometry was used to determine cell cycle and apoptosis. Results: We first showed that fenofibrate treatment reduced cell viability in HeLa cervical cancer cells in a dose-dependent manner at 24 h and 48 h. Importantly, fenofibrate-induced cell death was mediated through cell cycle arrest in the G0–G1 phase and caspase-dependent apoptosis. Moreover, fenofibrate also induced autophagy activation in a dose-dependent manner and pharmacological inhibition of autophagy led to increase of sub-G1 phase and caspase-dependent cell death in HeLa cells. Conclusion: In conclusion, these data demonstrated that fenofibrate initially induced cell cycle arrest, followed by caspase-3-dependent cell death in cervical cancer HeLa cells. However, fenofibrate also induced autophagy activation, which is closely related to the survival of diverse cancer cells, thus reducing the anticancer effects of fenofibrate. Therefore, the combination of an autophagy inhibitor and fenofibrate might have the potential to become a new therapeutic strategy for cervical cancer.

Preventative treatment with Fluorothiazinon suppressed Acinetobacter baumannii-associated septicemia in mice.

The high prevalence of multidrug-resistant Acinetobacter baumannii has emerged as a serious problem in the treatment of nosocomial infections in the past three decades. Recently, we developed a new small-molecule inhibitor belonging to a class of 2,4-disubstituted-4H-[1,3,4]-thiadiazine-5-ones, Fluorothiazinon (FT, previously called CL-55). FT effectively suppressed the T3SS of Chlamydia spp., Pseudomonas aeruginosa, and Salmonella sp. without affecting bacterial growth in vitro. In this study, we describe that prophylactic use of FT for 4 days prior to challenge with resistant clinical isolates of A. baumannii (ABT-897-17 and 52TS19) suppressed septic infection in mice, resulting in improved survival, limited bacteraemia and decreased bacterial load in the organs of the mice. We show that FT had an inhibitory effect on A. baumannii biofilm formation in vitro and, to a greater extent, on biofilm maturation. In addition, FT inhibited Acinetobacter isolate-induced death of HeLa cells, which morphologically manifested as apoptosis. The mechanism of FT action on A. baumannii is currently being studied. FT may be a promising candidate for the development of a broad-spectrum anti-virulence drug to use in the prevention of nosocomial infections.

Biodegradable polyphosphazene-based nanodrug to regulate redox homeostasis for augmented chemo-photodynamic therapy

Photodynamic therapy (PDT) is more precise than traditional tumor therapy. Nevertheless, PDT efficiency often is hindered by the antioxidant defense system which deplete the required reactive oxide species (ROS). Here we developed a simple but universal method by assembling anticancer drug (resveratrol, RV), photosensitizer (methylene blue, MB) and glutathione (GSH)-sensitive molecules (bis-(4-hydroxyphenyl)-disulfide, HPS) to covalent linking with hexachlorocyclotriphosphazene (HCCP) onto the Fe3O4 to construct a versatile drug delivery nanosystem (FHRHM). Notably, as a multifunctional nanodrug it shows good physiological stability, biocompatibility, and pH/GSH-responsive property to realize the RV and MB controlled release in tumor microenvironment (TME), maximum magnetic resonance (MR)/fluorescence (FL) imaging guided for synergistic chemo-photodynamic therapy (CT-PDT). Especially, the cross-linked FHRHM could be decomposed via reacting with high level of GSH to accelerate release MB for exogenous ROS generation, as well as disrupted disulfide bond (-S-S-) of HPS through depleting GSH to further reduce the endogenous ROS scavenging in TME, thus double amplifying the PDT and simultaneously enhancing CT to induce Hela cells death. This work highlights a novel strategy to construct TME-dissociable nanodrug for augmented CT-PDT via regulation of redox homeostasis, may provide a promising translational approach for tumor theranostics.

Root extract of Plumbago zeylanica L. induces cytotoxicity, inhibits cell migration and induces S-phase cell cycle arrest through down regulation of EGFR in HeLa cervical cancer cells

Plumbago zeylanica has been used in the traditional system of medicine from thousands of years owing to its potential therapeutic properties, however the anticancer and anti-metastatic effects are largely unknown against cervical cancer cells. In this study we demonstrated the cytotoxicity activity, inhibition of cell migration, induction of S-phase cell cycle arrest and the down regulation of expression level of epidermal growth factor receptor (EGFR) by ethanol extract of the root of P. zeylanica (ERPZ). The cytotoxicity effects were analyzed by MTT assay the IC50 was determined to be 10.49 ​μg/ml after 72 ​h of incubation. Besides, strong inhibition of wound healing activity was observed at 20 ​μg/ml concentration, where the wound size was reduced to 33%. The ethanol root extract of P. zeylanica also showed significant S-phase cell cycle arrest of 68.9% at 20 ​μg/ml concentration in HeLa cells which was accompanied by the down regulation of EGFR. Ethanol extracts of the root of P. zeylanica (ERPZ) treatment inhibited the growth of cervical cancer cells. The ERPZ arrested cells at the S-phase of the cell cycle. Besides the HRLC-MS analysis of ERPZ identified 15 compounds and among which the five major compounds such as 7,8-dihydroxy-4-methylcoumarin, neodiosmin, diosmetin, hispidulin, and formononetin were reported to possess antioxidant and anticancer activities, could plausibly induce cell death in HeLa cells.

Low-dose exposure to phytosynthesized gold nanoparticles combined with glutamine deprivation enhances cell death in the cancer cell line HeLa via oxidative stress-mediated mitochondrial dysfunction and G0/G1 cell cycle arrest.

Cancer cells use nutrients like D-glucose (Glc) and L-glutamine (Q) more efficiently for their development. This increased nutritional dependency of malignant cells has been commonly employed in various in vitro and in vivo models of anticancer therapies. This study utilized a combination of a low dose (25 μg mL-1) of S2, a phytosynthesized gold nanoparticle (AuNP) that was previously proven to be non-toxic, and deprivation of extracellular glutamine as an anticancer strategy in the human cervical cancer cell line HeLa. We discovered that 24 h Q deprivation led to a less significant decrease in the viability of HeLa cells while a low dose of S2 caused a non-significant reduction in the viability of HeLa cells. However, combining these two treatments resulted in highly significant inhibition of cell growth, as measured by the MTT test and morphological examination. Glutamine starvation in HeLa cells was found to induce cellular uptake of S2 via clathrin-mediated endocytosis, thus facilitating the improved antitumor effects of the combined treatment. Flow cytometry-based assays using fluorescent probes H2DCFDA and MitoSOX Red confirmed that this combination therapy involved the development of oxidative stress conditions owing to a surplus of cytosolic reactive oxygen species (cytoROS) and mitochondrial superoxide (mtSOX) generation. Furthermore, the investigated combinatorial treatment also indicated mitochondrial inactivity and disintegration, as evidenced by the drop in the mitochondrial membrane potential (Δψm) and the decrease in the mitochondrial mass (mtMass) in a flow-cytometric assay utilizing the probes. Tetramethylrhodamine ethyl ester and MitoTracker Green FM, respectively. Cell cycle arrest in the G0/G1 phase, induction of cell death via apoptosis/necrosis, and inhibition of migration capacities of HeLa cells were also seen after the combined treatment. Thus, this research provides insight into a new combinatorial approach for reducing the dose of nanoparticles and increasing their efficacy to better inhibit the growth of human cervical cancer cells by leveraging their extracellular glutamine dependence.

Anticancer, anti-inflammatory, and apoptotic activities of MAT20, a poly-herbal formulation.

Cancer is a disease that can be treated with surgery, chemotherapy, and radiation. Although these methods are very effective, they often result in micro-metastasis, drug resistance, and radio resistance. Disease relapse can be treated by escalating drug dosages, but this approach leads to drug resistance and drug toxicity. Complementary and Alternative Medicines (CAM) is a treatment which involves the the simultaneous administration of herbal formulations and chemotherapy, where the herbal formulations could mitigate the negative effects of chemotherapy, resulting in better outcomes. In this study, the efficacy of our formulation MAT20, a crude extract of the moringa, amla, and tulsi leaves, was investigated in terms of its cytotoxic and inflammatory properties. We hypothesized that MAT20, would induce higher HeLa cell death compared to other extracts of individual plants. Significantly lower IC50 values were found in 48 hours of exposure compared to any other individual extracts of the plant part. Also, we investigated the effects of MAT20 on the expression of COX2, a marker for inflammation on HeLa cells. Finally, to understand the mechanism of action, we studied the upregulation of the BAX gene and downregulation of the BCL2 gene by MAT20. Our study demonstrated significant cell cytotoxicity and DNA fragmentation upon the exposure of HeLa cells to the drug, substantiating our hypothesis. Treatment with MAT20 suppressed PMA-mediated induction of the COX2 gene. Our data is important for understanding the anti-cancer and anti-inflammatory properties of MAT20.

Chemical structures and induction of cell death via heat shock protein inhibition of the prenylated phloroglucinol derivatives isolated from Hypericum erectum

Four new prenylated phloroglucinol derivatives (+)-erectumol I (1a), (−)-erectumol I (1b), (−)-erectumol II (2a), and (+)-erectumol II (2b) were isolated from the methanol extracts of the whole plants of Hypericum erectum. These new compounds were isolated as a pair of enantiomers, respectively. The planar chemical structures and relative configurations of the new compounds were suggested by Cu-Kα X-ray diffraction analysis and been confirmed by high-resolution mass and 1D and 2D NMR spectroscopic data. The absolute configuration of the four new compounds were established by comparing the experimental and predicted electronic circular dichroism data. Isolated compounds 1b and 2b induced death of Adriamycin-treated HeLa cells. Their enantiomers 1a and 2a did not. In addition, the apparent mechanism of cell death of 1b was the inhibited expression of heat shock protein 105.

Blockade of endoplasmic reticulum stress-induced cell death by Ureaplasma parvum vacuolating factor.

Previously, we found that Ureaplasma parvum internalised into HeLa cells and cytosolic accumulation of galectin-3. U. parvum induced the host cellular membrane damage and survived there. Here, we conducted vesicular trafficking inhibitory screening in yeast to identify U. parvum vacuolating factor (UpVF). U. parvum triggered endoplasmic reticulum (ER) stress and upregulated the unfolded protein response-related factors, including BiP, P-eIF2 and IRE1 in the host cells, but it blocked the induction of the downstream apoptotic factors. MicroRNA library screening of U. parvum-infected cells and UpVF-transfected cells identified miR-211 and miR-214 as the negative regulators of the apoptotic cascade under ER stress. Transient expression of UpVF induced HeLa cell death with intracellular vacuolization; however, some stable UpVF transformant survived. U. parvum-infected cervical cell lines showed resistance to actinomycin D, and UpVF stable transformant cell lines exhibited resistance to X-ray irradiation, as well as cisplatin and paclitaxel. UpVF expressing cervical cancer xenografts in nude mice also acquired resistance to cisplatin and paclitaxel. A mycoplasma expression vector based on Mycoplasma mycoides, Syn-MBA (multiple banded antigen)-UpVF, reduced HeLa cell survival compared with that of Syn-MBA after 72 hr of infection. These findings together suggest novel mechanisms for Ureaplasma infection and the possible implications for cervical cancer malignancy. TAKE AWAYS: • Ureaplasmal novel virulence factor, UpVF, was identified. • UpVF triggered ER stress but suppressed apoptotic cascade via miR-211 and -214. • UpVF conferred resistance to anticancer treatments both in vivo and in vitro. • Dual expression of MBA and UpVF in JCVI-syn3B showed host cell damage.

Controlled killing of human cervical cancer cells by combined action of blue light and C-doped TiO2 nanoparticles.

In this study, C-doped TiO2 nanoparticles (C-TiO2) were prepared and tested as a photosensitizer for visible-light-driven photodynamic therapy against cervical cancer cells (HeLa). X-ray diffraction and Transmission Electron Microscopy confirmed the anatase form of nanoparticles, spherical shape, and size distribution from 5 to 15nm. Ultraviolet-visible light spectroscopy showed that C doping of TiO2 enhances the optical absorption in the visible light range caused by a bandgap narrowing. The photo-cytotoxic activity of C-TiO2 was investigated in vitro against HeLa cells. The lack of dark cytotoxicity indicates good biocompatibility of C-TiO2. In contrast, a combination with blue light significantly reduced the survival of HeLa cells: illumination only decreased cell viability by 30% (15min of illumination, 120µW power), and 60% when HeLa cells were preincubated with C-TiO2. We have also confirmed blue light-induced C-TiO2-catalyzed generation of reactive oxygen species in vitro and intracellularly. Oxidative stress triggered by C-TiO2/blue light was the leading cause of HeLa cell death. Fluorescent labeling of treated HeLa cells showed distinct morphological changes after the C-TiO2/blue light treatment. Unlike blue light illumination, which caused the appearance of large necrotic cells with deformed nuclei, cytoplasm swelling, and membrane blebbing, a combination of C-TiO2/blue light leads to controlled cell death, thus providing a better outcome of local anticancer therapy.

ZAR1 resistosome and helper NLRs: Bringing in calcium and inducing cell death

ZAR1 resistosome and helper NLRs: Bringing in calcium and inducing cell death