Mitochondrial superoxide anions induced by exogenous oxidative stress determine tumor cell fate: an individual cell-based study.

Objective: Reactive oxygen species (ROS) are involved in a variety of biological phenomena and serve both deleterious and beneficial roles. ROS quantification and assessment of reaction networks are desirable but difficult because of their short half-life and high reactivity. Here, we describe a pro-oxidative model in a single human lung carcinoma SPC-A-1 cell that was created by application of extracellular HO stimuli.

Single tumor-initiating cells evade immune clearance by recruiting type II macrophages.

Tumor infiltrated type II (M2) macrophages promote tumorigenesis by suppressing immune clearance, promoting proliferation, and stimulating angiogenesis. Interestingly, macrophages were also found to enrich in small foci of altered hepatocytes containing liver tumor-initiating cells (TICs). However, whether and how TICs specifically recruit macrophages and the function of these macrophages in tumor initiation remain unknown due to technical difficulties.

Oleanolic acid induces autophagic death in human gastric cancer cells in vitro and in vivo.

Oleanolic acid (OA), a plant-derived pentacyclic terpenoid, is known to have hepatoprotective effects. In this study, we found that OA induced autophagic cell death in multiple human gastric cancer cell lines. Moreover, OA-induced autophagy was shown for the first time in human gastric cancer cells, evidenced by the formation of GFP-RFP-LC3 puncta and autophagosomes.

A miR-130a-YAP positive feedback loop promotes organ size and tumorigenesis.

Organ size determination is one of the most intriguing unsolved mysteries in biology. Aberrant activation of the major effector and transcription co-activator YAP in the Hippo pathway causes drastic organ enlargement in development and underlies tumorigenesis in many human cancers. However, how robust YAP activation is achieved during organ size control remains elusive.

[Pro-apoptotic effects of luteolin on hepatoma HepG2 cells].

Objective: To investigate the effect of luteolin on cell growth and apoptosis of HepG2 cells in vitro.

Methods: Cultured HepG2,HL60,A549 and LO2 cells were treated with luteolin for different doses (0 μg/ml,2.5 μg/ml,10 μg/ml and 20 μg/ml) and varied times (0 h,24 h,48 h and 72 h).

Fe-SOD cooperates with Nutlin3 to selectively inhibit cancer cells in vitro and in vivo.

Nutlin3, a non-genotoxic agonist of p53, is currently in phase II clinical trials for cancer treatment. However, its effects on normal tissues and cell types remain largely to be determined. Drugs that can selectively target cancer cells as well as cooperate with the p53 pathway are thus greatly needed.

Anti-proliferative effects of the novel squamosamide derivative (FLZ) on HepG2 human hepatoma cells by regulating the cell cycle-related proteins are associated with decreased Ca(2+)/ROS levels.

FLZ is a synthetic novel squamosamide derivative and has previously been proved to be a potential drug for Parkinson's disease and Alzheimer's disease. FLZ has strong antioxidant activity, which implies that FLZ could eliminate excessive intracellular reactive oxygen species (ROS) in tumor cells and induce a pathway related to low cellular ROS levels, thereby inhibiting tumor cells proliferation. However, few reports have focused on the antitumor effects of FLZ.

3-(4-(Benzo[d]thiazol-2-yl)-1-phenyl-1H-pyrazol-3-yl) phenyl acetate induced Hep G2 cell apoptosis through a ROS-mediated pathway.

3-(4-(Benzo[d]thiazol-2-yl)-1-phenyl-1H-pyrazol-3-yl) phenyl acetate (DPB-5) is a synthetic benzothiazole derivative. In the present study, we revealed that DPB-5 had strong cytotoxicity to induce cell apoptosis, which was mediated by ROS. And DPB-5 was more cytotoxic toward hepatoma cells than toward normal hepatic cells, which was resulted from the greater susceptibility of the malignant cells to ROS.

Proliferative and anti-proliferative effects of thymosin alpha1 on cells are associated with manipulation of cellular ROS levels.

Reactive oxygen species (ROS) are constantly generated and eliminated in the biological system and play important roles in a variety of physiological and pathological processes. Previous studies indicate that modulation of cellular ROS affects cell proliferation. Thymosin alpha 1 (Talpha1) is a naturally occurring thymic peptide and has previously been shown to be a potential therapy for some immunodeficiencies, malignancies, and infections.

Expression and hydroxylamine cleavage of thymosin alpha 1 concatemer.

Human thymosin alpha 1 (Talpha1) is an important peptide in the development and senescence of immunological competence in human, and many studies have reported the expression of this peptide. In this study, we designed and synthesized the Talpha1 gene according to the E. coli codon usage preference and constructed a 6xTalpha1 concatemer.

Apoptosis-inducing effects of two anthraquinones from Hedyotis diffusa WILLD.

Two anthraquinones which inhibit activity of the Src tyrosine kinase were isolated from a water extract of Hedyotis diffusa WILLD. and identified as 2-hydroxy-3-methylanthraquinone (compound 1) and 1-methoxy-2-hydroxyanthraquinone (compound 2). Both compounds showed inhibitory activity against protein tyrosine kinases v-src and pp60src and arrested the growth of SPC-1-A, Bcap37 and HepG2 cancer cells.

Mitochondrial ROS burst as an early sign in sarsasapogenin-induced apoptosis in HepG2 cells.

Sarsasapogenin is a steroidal sapogenin with antitumor properties. To explain the mechanism of its apoptotic effect, mitochondrial activity was assessed via a 3,(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Flow cytometry (FCM) was used to estimate the changes in mitochondrial membrane potential (MMP), reactive oxygen species (ROS) generation, and cellular-reduced glutathione (GSH) level.

Anti-proliferative effects of recombinant iron superoxide dismutase on HepG2 cells via a redox-dependent PI3k/Akt pathway.

The coding sequence for an iron superoxide dismutase (fe-sod) was amplified from the Nostoc commune genome. Recombinant Fe-SOD was overexpressed in Escherichia coli, accounting for approximately 76% of total bacterial protein. Fe-SOD was purified from bacterial lysate by Ni-NTA column chromatography and used to generate an anti-SOD antibody.

Intracellular labeling method for chip-based capillary electrophoresis fluorimetric single cell analysis using liposomes.

An intracellular derivatization method mediated by liposome was developed for single cell analysis with chip-based capillary electrophoresis (CE) and laser-induced fluorescence (LIF) detection. Liposomes with an average diameter of 100 nm were produced from phosphatidylcholine to encapsulate fluorescent dyes by an ultrasonic method. The encapsulation yield and the vesicle density were determined to be 46+/-5% and 8.

Expression, purification, and bioactivity of GST-fused v-Src from a bacterial expression system.

v-Src is a non-receptor protein tyrosine kinase involved in many signal transduction pathways and closely related to the activation and development of cancers. We present here the expression, purification, and bioactivity of a GST (glutathione S-transferase)-fused v-Src from a bacterial expression system. Different culture conditions were examined in an isopropyl beta-D-thiogalactopyranoside (IPTG)-regulated expression, and the fused protein was purified using GSH (glutathione) affinity chromatography.

Cloning, expression, purification, and characterization of LC-1 ScFv with GFP tag.

Total RNA was isolated from the hybridoma cell line (LC-1), which secretes anti-lung adenocarcinoma monoclonal antibody, and was transferred into cDNA. Based on the FR1 (framework region 1) and FR4 conserved regions of LC-1 gene, the variable regions of heavy chain (Vh) and light chain (Vl) were amplified, and the Vh and modified Vl were connected to single chain Fv (ScFv) by SOE-PCR (splice overlap extension PCR). The modified ScFv was fused with green fluorescent protein (GFP) and introduced into E.

[Establishment of mouse melanoma model expressing beta-galactosidase and its application in the research of DNA vaccines against tumor].

We established a mouse melanoma model expressing beta-galactosidase for the study of tumor immunotherapy. The recombinant vector p3gal was constructed by inserting a beta-galactosidase gene into the MCS of plasmid pcDNA3. The vector then transfected the B16 cells.

[Effective expression of ribonuclease-onconase in Escherichia coli and assaying its cytotoxic potential].

Onconase, a ribonuclease purified from Rana pipiens oocytes, has cytotoxic activity against several tumor cell lines in vitro. With the characteristic of containing four pairs of disulfide bonds internal and N terminal sequence attributing mostly to its biological functions, it is difficult to obtain the active Onconase from Escherichia coli expression system with normal strategy. Here, we fused the cDNA coding for Onconase in frame with the pelB signal sequence in pET22b(+) expression vector.

Cloning and GST-fused expression in E. coli of mouse beta-1,4-galactosyltransferase.

Beta-1,4-galactosyltransferase (beta4Gal-T) (EC 2.4.1.