• Journal of Life Science
• /
• v.23 no.10
• /
• pp.1252-1259
• /
• 2013

To investigate the effects of a fibrinolytic enzyme, BK-17, on the growth of human cancer cells, we performed various biochemical experiments, including cell proliferation and viability, and investigated subsequent morphological changes and apoptosis induction. BK-17 treatment of AGS human gastric and T24 human bladder carcinoma cells decreased the viability and the proliferation of the cells in a concentration-dependent manner. Microscopic studies indicated that the antiproliferative effects of the BK-17 treatment were associated with morphological changes, such as membrane shrinking, cell rounding up, and the formation of apoptotic bodies, indicating that BK-17 induced apoptosis in the cell lines. Of note, RT-PCR and Western blotting data indicated that the BK-17 treatment induced the down-regulation of antiapoptotic Bcl-2 members, Bcl-2 and $Bcl-X_L$, and the up-regulation of proapoptotic Bax members, Bax and Bad, in the AGS cells. BK-17-induced apoptosis of AGS cells was involved in the proteolytic activation of caspase-3, caspase-8, and caspase-9. Taken together, these findings suggest that BK-17 is associated with the induction of apoptotic cell death.

• Journal of Microbiology and Biotechnology
• /
• v.26 no.11
• /
• pp.1881-1890
• /
• 2016

Manganese superoxide dismutase (MnSOD) is a vital enzyme that protects cells from free radicals through eliminating superoxide radicals ($O^{2-}$). Hirudin, a kind of small active peptide molecule, is one of the strongest anticoagulants that can effectively cure thrombus diseases. In this study, we fused Hirudin to the C terminus of human MnSOD with the GGGGS linker to generate a novel dual-feature fusion protein, denoted as hMnSOD-Hirudin. The hMnSOD-Hirudin gene fragment was cloned into the pET15b (SmaI, CIAP) vector, forming a recombinant pET15b-hMnSOD-Hirudin plasmid, and then was transferred into Escherichia coli strain Rosetta-gami for expression. SDS-PAGE was used to detect the fusion protein, which was expected to be about 30 kDa upon IPTG induction. Furthermore, the hMnSOD-Hirudin protein was heavily detected as a soluble form in the supernatant. The purification rate observed after Ni NTA affinity chromatography was above 95%. The hMnSOD-Hirudin protein yield reached 67.25 mg per liter of bacterial culture. The identity of the purified protein was confirmed by western blotting. The hMnSOD-Hirudin protein activity assay evinced that the antioxidation activity of the hMnSOD-Hirudin protein obtained was $2,444.0{\pm}96.0U/mg$, and the anticoagulant activity of the hMnSOD-Hirudin protein was $599.0{\pm}35.0ATU/mg$. In addition, in vitro bioactivity assay showed that the hMnSOD-Hirudin protein had no or little cytotoxicity in H9c2, HK-2, and H9 (human $CD_4{^+}$, T cell) cell lines. Transwell migration assay and invasion assay showed that the hMnSOD-Hirudin protein could suppress human lung cancer 95-D cell metastasis and invasion in vitro.

• Biomolecules & Therapeutics
• /
• v.25 no.2
• /
• pp.213-221
• /
• 2017

Baicalein, a natural flavonoid obtained from the rhizome of Scutellaria baicalensis Georgi, has been reported to have anticancer activities in several human cancer cell lines. However, its antimetastatic effects and associated mechanisms in melanoma cells have not been extensively studied. The current study examined the effects of baicalein on cell motility and anti-invasive activity using mouse melanoma B16F10 cells. Within the noncytotoxic concentration range, baicalein significantly inhibited the cell motility and invasiveness of B16F10 cells in a concentration-dependent manner. Baicalein also reduced the activity and expression of matrix metalloproteinase (MMP)-2 and -9; however, the levels of tissue inhibitor of metalloproteinase-1 and -2 were concomitantly increased. The inhibitory effects of baicalein on cell motility and invasiveness were found to be associated with its tightening of tight junction (TJ), which was demonstrated by an increase in transepithelial electrical resistance and downregulation of the claudin family of proteins. Additionally, treatment with baicalein markedly reduced the expression levels of lipopolysaccharide-induced phosphorylated Akt and the invasive activity in B16F10 cells. Taken together, these results suggest that baicalein inhibits B16F10 melanoma cell migration and invasion by reducing the expression of MMPs and tightening TJ through the suppression of claudin expression, possibly in association with a suppression of the phosphoinositide 3-kinase/Akt signaling pathway.

• Journal of Ginseng Research
• /
• v.45 no.1
• /
• pp.48-57
• /
• 2021

Background: Ginsenoside Rh2 is well known for many pharmacological activities, such as anticancer, antidiabetes, antiinflammatory, and antiobesity properties. Glycosyltransferases (GTs) are ubiquitous enzymes present in nature and are widely used for the synthesis of oligosaccharides, polysaccharides, glycoconjugates, and novel derivatives. We aimed to synthesize new ginsenosides from Rh2 using the recombinant GT enzyme and investigate its cytotoxicity with diverse cell lines. Methods: We have used a GT gene with 1,224-bp gene sequence cloned from Lactobacillus rhamnosus (LRGT) and then expressed in Escherichia coli BL21 (DE3). The recombinant GT protein was purified and demonstrated to transform Rh2 into two novel ginsenosides, and they were characterized by nuclear magnetic resonance (NMR) techniques and evaluated by 3-(4, 5-dimethylthiazol-2-yl)-2-5-diphenyltetrazolium bromide assay. Results: Two novel ginsenosides with an additional glucopyranosyl (6→1) and two additional glucopyranosyl (6→1) linked with the C-3 position of the substrate Rh2 were synthesized, respectively. Cell viability assay in the lung cancer (A549) cell line showed that glucosyl ginsenoside Rh2 inhibited cell viability more potently than ginsenoside Rg3 and Rh2 at a concentration of 10 μM. Furthermore, glucosyl ginsenoside Rh2 did not exhibit any cytotoxic effect in murine macrophage cells (RAW264.7), mouse embryo fibroblasts cells (3T3-L1), and skin cells (B16BL6) at a concentration of 10 μM compared with ginsenoside Rh2 and Rg3. Conclusion: This is the first report on the synthesis of two novel ginsenosides, namely, glucosyl ginsenoside Rh2 and diglucosyl ginsenoside Rh2 from Rh2 by using recombinant GT isolated from L. rhamnosus. Moreover, diglucosyl ginsenoside Rh2 might be a new candidate for treatment of inflammation, obesity, and skin whiting, and especially for anticancer.

• Journal of Life Science
• /
• v.19 no.5
• /
• pp.633-638
• /
• 2009

We investigated the inhibitory effects of solvent extracts from dried tuna on the growth of cancer cell lines (HT1080 human fibrosarcoma and HT-29 human colon cancer cells) and $H_2O_2$-induced oxidative stress. Inhibitory effects of acetone with methylene chloride (A+M) and methanol (MeOH) extracts on the growth of HT1080 and HT-29 cancer cells increased in a dose dependent manner (p<0.05). The inhibitory effect was more significant on the growth of HT1080 cells, and A+M extracts had a higher inhibitory effect compared to MeOH extracts. The treatments of hexane, 85% aq. methanol, butanol and water fractions significantly inhibited the growth of both cancer cells (p<0.05). Among the fractions, hexane and 85% aq. methanol fractions showed higher inhibitory effects. In order to determine the protective effect on $H_2O_2$-induced oxidative stress, a DCHF-DA (dichlorodihydrofluorescin diacetate) assay was conducted. All fractions, including crude extracts of dried tuna, appeared to significantly reduce the levels of intracellular reactive oxygen species (ROS) with dose responses (p<0.05). Among the fractions, BuOH and 85% methanol fractions showed a higher protective effect on the production of lipid peroxides. These results indicate that the consumption of tuna may be recommended as a potent functional food for preventing cellular oxidation and cancer.

• Journal of Life Science
• /
• v.29 no.10
• /
• pp.1062-1070
• /
• 2019

A components of garlic (Allium sativum) have anti-proliferative effects against various types of cancer. We aimed to investigate the capacity of garlic compounds to anti-tumor on a various cancer cell lines. Fractionation of garlic extract, guided by antiproliferative activity against human gastric cancer (AGS) cells, has resulted in the isolation of N-benzyl-N-methyldecan-1-amine (NBNMA). We investigated the effect of newly isolated NBNMA from garlic cloves on the inhibition of the growth of CT-26, AGS, HepG2, HCT-116, MCF7, B16F10, and Sarcoma-180 cells for in vitro and CT-26 colon carcinoma cells in vivo. NBNMA exhibited an antiproliferative effect in CT-26 cells by apoptotic cell death. NBNMA exhibited down-regulation of anti-apoptotic Bcl-2 proteins and up-regulation of apoptotic Bad protein expression in western blot analyses. In addition, NBNMA meagre activated caspase 3 and caspase 9, initiator caspases of the extrinsic and intrinsic pathways of apoptosis. NBNMA treatment at a dose of 10 mg/kg for 21 days in experimental mice implanted with tumors resulted in significant reduction of the tumor weight (43%). NBNMA exhibited both in vitro and in vivo anticancer activity. These results indicate that NBNMA has promising potential to become a novel anticancer agent from garlic cloves for the treatment of colon carcinoma cancer.

• IMMUNE NETWORK
• /
• v.1 no.1
• /
• pp.45-52
• /
• 2001

Background: Many types of cancer become resistant to current chemotherapeutic and radiotherapeutic intervention. To overcome this situation application of gene therapy by the introduction of suicide genes followed by their prodrugs may be promising. A viral enzyme, Herpes simplex thymidine kinase (HSV-tk), which converts ganciclovir from an inactive prodrug to a cytotoxic agent by phosphorylation, are being actively investigated for use in gene therapy for cancer. The purpose of this study was to determine whether combining prodrug-activating gene therapy and irradiation might result in enhanced antitumor effects. Methods: The HSV-tk gene was cloned into the retroviral vector, pLXSN and established the clones producing retroviruses carrying the HSV-tk gene. The carcinoma cell line, HCT116 and Huh-7 were transduced with high-titer recombinant retroviruses. These cell lines were treated with ganciclovir before or after irradiation for the defining combinational effect of suicide gene therapy and radiotherapy. Results: The titers of cloned PA3 17 amphotropic retroviruses ranged from 4 to 6 X $10^6CFU/ml4$. After selectional periods, the expression of HSV-tk was confirmed by reverse-transcriptase polymerase chain reaction (RT-PCR). The growth of cells expressing HSV-tk was inhibited as increase of GCV dose after 48 hr and the growth inhibitory effect of GCV was much higher after 72 hr. When the cells transduced with HSV-tk gene were exposed to radiation, the growth inhibitory effect of GCV was significantly increased, as compared with non-transduced parental cells. Conclusions: The results suggest that the addition of HSV-tk gene therapy to standard radiation therapy may improve the effectiveness of treatment for solid tumors.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.11
• /
• pp.4555-4561
• /
• 2014

Background: Silencing due to methylation of suppressor of cytokine signaling-3 (SOCS-3), a negative regulator gene for the JAK/STAT signaling pathway has been reported to play important roles in leukemogenesis. Imatinib mesylate is a tyrosine kinase inhibitor that specifically targets the BCR-ABL protein and induces hematological remission in patients with chronic myeloid leukemia (CML). Unfortunately, the majority of CML patients treated with imatinib develop resistance under prolonged therapy. We here investigated the methylation profile of SOCS-3 gene and its downstream effects in a BCR-ABL positive CML cells resistant to imatinib. Materials and Methods: BCR-ABL positive CML cells resistant to imatinib (K562-R) were developed by overexposure of K562 cell lines to the drug. Cytotoxicity was determined by MTS assays and $IC_{50}$ values calculated. Apoptosis assays were performed using annexin V-FITC binding assays and analyzed by flow cytometry. Methylation profiles were investigated using methylation specific PCR and sequencing analysis of SOCS-1 and SOCS-3 genes. Gene expression was assessed by quantitative real-time PCR, and protein expression and phosphorylation of STAT1, 2 and 3 were examined by Western blotting. Results: The $IC_{50}$ for imatinib on K562 was 362nM compared to 3,952nM for K562-R (p=0.001). Percentage of apoptotic cells in K562 increased upto 50% by increasing the concentration of imatinib, in contrast to only 20% in K562-R (p<0.001). A change from non-methylation of the SOCS-3 gene in K562 to complete methylation in K562-R was observed. Gene expression revealed down-regulation of both SOCS-1 and SOCS-3 genes in resistant cells. STAT3 was phosphorylated in K562-R but not K562. Conclusions: Development of cells resistant to imatinib is feasible by overexposure of the drug to the cells. Activation of STAT3 protein leads to uncontrolled cell proliferation in imatinib resistant BCR-ABL due to DNA methylation of the SOCS-3 gene. Thus SOCS-3 provides a suitable candidate for mechanisms underlying the development of imatinib resistant in CML patients.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.5
• /
• pp.2153-2158
• /
• 2014

Beclin 1 is a key factor for initiation and regulation of autophagy, which is a cellular catabolic process involved in tumorigenesis. To investigate the role of alternative splicing of Beclin1 in the regulation of autophagy in leukemia cells, Beclin1 mRNA from 6 different types of cell lines and peripheral blood mononuclear cells from 2 healthy volunteers was reversely transcribed, subcloned, and screened for alternative splicing. New transcript variants were analyzed by DNA sequencing. A transcript variant of Beclin 1 gene carrying a deletion of exon 11, which encoded a C-terminal truncation of Beclin 1 isoform, was found. The alternative isoform was assessed by bioinformatics, immunoblotting and subcellular localization. The results showed that this variable transcript is generated by alternative 3' splicing, and its translational product displayed a reduced activity in induction of autophagy by starvation, indicating that the spliced isoform might function as a dominant negative modulator of autophagy. Our findings suggest that the alternative splicing of Beclin 1 might play important roles in leukemogenesis regulated by autophagy.

• Korean Journal of Medicinal Crop Science
• /
• v.10 no.2
• /
• pp.139-143
• /
• 2002

Ixeris dentate was used to extract the natural compounds with methanol and then the extracts were further fractionated using n-hexane, ethyl acetate, butanol and aqueous fraction. The methanol extract of Ixeris dentate had strong antimutagenic effect in Ames mutagenicity test. Among the extracts fractioned from the methanol extract, the butanol fraction exhibited the greatest antimutagenic effect suppressing the mutagenicity of Salmonella typhimurium TA100 with inhibition rate of 88.93%. Cancer cell lines include human lung carcinoma(A549), human breast adenocarcinoma(MCF-7) and human hepatocellular carcinoma(Hep3B). Hexane fraction showed the strongest effect against A549, MCF-7 and Hep3B at the same concentration compared to those of other fractions.