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1.
Chem Commun (Camb) ; 58(24): 3925-3928, 2022 Mar 22.
Article in English | MEDLINE | ID: mdl-35244125

ABSTRACT

Adjuvants are important components in vaccines to increase the immunogenicity of proteins and induce optimal immunity. In this study, we designed a novel ternary adjuvant system Alum + c-GAMP + poly(I:C) with STING agonist 3,3'-c-GAMP (c-GAMP) and TLR3 agonist poly(I:C) co-adsorbed on the conventional adjuvant aluminum gel (Alum), and further constructed an S1 protein vaccine. Two doses of vaccination with the ternary adjuvant vaccine were sufficient to induce a balanced Th1/Th2 immune response and robust humoral and cellular immunity. Additionally, the ternary adjuvant group had effective neutralizing activity against live virus SARS-CoV-2 and pseudovirus of all variants of concern (alpha, beta, gamma, delta and omicron). These results indicate that the ternary adjuvants have a significant synergistic effect and can rapidly trigger potent immune responses; the combination of the ternary adjuvant system with S1 protein is a promising COVID-19 vaccine candidate.


Subject(s)
COVID-19 , SARS-CoV-2 , Adjuvants, Immunologic/pharmacology , Alum Compounds , Aluminum , Animals , Antibodies, Viral , COVID-19/prevention & control , COVID-19 Vaccines/pharmacology , Humans , Immunity, Cellular , Mice , Mice, Inbred BALB C , Poly I
2.
Chem Commun (Camb) ; 58(13): 2120-2123, 2022 Feb 10.
Article in English | MEDLINE | ID: mdl-35040862

ABSTRACT

The coronavirus 2019 (COVID-19) pandemic is causing serious impacts in the world, and safe and effective vaccines and medicines are the best methods to combat the disease. The receptor-binding domain (RBD) of the SARS-CoV-2 spike protein plays a key role in interacting with the angiotensin-converting enzyme 2 (ACE2) receptor, and is regarded as an important target of vaccines. Herein, we constructed the adjuvant-protein conjugate Pam3CSK4-RBD as a vaccine candidate, in which the N-terminal of the RBD was site-selectively oxidized by transamination and conjugated with the TLR1/2 agonist Pam3CSK4. This demonstrated that the conjugation of Pam3CSK4 significantly enhanced the anti-RBD antibody response and cellular response. In addition, sera from the Pam3CSK4-RBD immunized group efficiently inhibited the binding of the RBD to ACE2 and protected cells from SARS-CoV-2 and four variants of concern (alpha, beta, gamma and delta), indicating that this adjuvant strategy could be one of the effective means for protein vaccine development.


Subject(s)
COVID-19/prevention & control , Lipopeptides/chemistry , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/chemistry , Vaccines, Conjugate/immunology , Angiotensin-Converting Enzyme 2/metabolism , Animals , Antibody Formation , Antigens, CD/metabolism , Antigens, Differentiation, Myelomonocytic/metabolism , COVID-19/virology , Female , HEK293 Cells , Humans , Macrophages/cytology , Macrophages/immunology , Macrophages/metabolism , Mice , Mice, Inbred BALB C , Protein Binding , Protein Domains/immunology , RAW 264.7 Cells , Recombinant Proteins/biosynthesis , Recombinant Proteins/immunology , SARS-CoV-2/isolation & purification , SARS-CoV-2/metabolism , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology , Spike Glycoprotein, Coronavirus/metabolism , Vaccines, Conjugate/administration & dosage , Vaccines, Conjugate/chemistry
3.
J Med Chem ; 65(3): 2558-2570, 2022 02 10.
Article in English | MEDLINE | ID: mdl-35073081

ABSTRACT

Safe and effective vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its variants are the best approach to successfully combat the COVID-19 pandemic. The receptor-binding domain (RBD) of the viral spike protein is a major target to develop candidate vaccines. α-Galactosylceramide (αGalCer), a potent invariant natural killer T cell (iNKT) agonist, was site-specifically conjugated to the N-terminus of the RBD to form an adjuvant-protein conjugate, which was anchored on the liposome surface. This is the first time that an iNKT cell agonist was conjugated to the protein antigen. Compared to the unconjugated RBD/αGalCer mixture, the αGalCer-RBD conjugate induced significantly stronger humoral and cellular responses. The conjugate vaccine also showed effective cross-neutralization to all variants of concern (B.1.1.7/alpha, B.1.351/beta, P.1/gamma, B.1.617.2/delta, and B.1.1.529/omicron). These results suggest that the self-adjuvanting αGalCer-RBD has great potential to be an effective COVID-19 vaccine candidate, and this strategy might be useful for designing various subunit vaccines.


Subject(s)
COVID-19 Vaccines/therapeutic use , COVID-19/therapy , Galactosylceramides/therapeutic use , Peptide Fragments/therapeutic use , SARS-CoV-2/immunology , Vaccines, Conjugate/therapeutic use , Adjuvants, Immunologic/chemistry , Adjuvants, Immunologic/therapeutic use , Animals , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19 Vaccines/chemistry , COVID-19 Vaccines/immunology , Female , Galactosylceramides/chemistry , Galactosylceramides/immunology , Immunity, Humoral/drug effects , Immunity, Innate/drug effects , Interferon-gamma/metabolism , Liposomes/chemistry , Liposomes/immunology , Liposomes/therapeutic use , Mice, Inbred BALB C , Peptide Fragments/chemistry , Peptide Fragments/immunology , Protein Domains , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/immunology , Spike Glycoprotein, Coronavirus/therapeutic use , Vaccines, Conjugate/chemistry , Vaccines, Conjugate/immunology
4.
Medicine (Baltimore) ; 98(39): e17198, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31574828

ABSTRACT

BACKGROUND: The aim of our study was to assess the value of serum human epididymis protein 4 (HE4) to diagnose lung cancer and provide reliable scientific conclusions to guide clinical practice. METHODS: A systematic search of the PubMed, EMBASE, Cochrane Library, Chinese National Knowledge Infrastructure, Chinese Biomedical Literature, and WANFANG databases was conducted to identify all studies examining serum HE4 in the diagnosis of lung cancer published up to June, 2017. The Quality Assessment of Diagnostic Accuracy Studies tool was used to evaluate the methodological quality of each trial. The meta-analysis was performed using STATA software and Review Manager 5.3. RESULTS: There were 21 studies involving 1883 cases and 1696 controls included in our meta-analysis. The pooled sensitivity and specificity of HE4 for diagnosing lung cancer were 0.73 (95% confidence interval [CI] 0.68-0.78) and 0.86 (95% CI 0.81-0.91), respectively. The positive likelihood ratio and negative likelihood ratio were 5.4 (95% CI 3.8-7.5) and 0.31 (95% CI 0.26-0.37), respectively. The diagnostic odds ratio was 17 (95% CI 12-26). The area under the curve of the summary receiver-operating characteristic curve was 0.86 (95% CI 0.83-0.89). Race, assay method, type of cancer, sample size, and publication date might be sources of heterogeneity in our meta-analysis. Subgroup analyses showed that the sensitivity in Caucasians was higher than that in Asians (0.81, 95% CI 0.71-0.91; and 0.71, 95% CI 0.66-0.77, respectively), but the specificity in Asians was better than that in Caucasians (0.87, 95% CI 0.81-0.92; and 0.85, 95% CI 0.73-0.97, respectively). The chemiluminescent microparticle immunoassay had the highest sensitivity, with 0.79 (95% CI 0.73-0.97), and the enzyme-linked immunosorbent assay had the highest specificity, with 0.87 (95% CI 0.79-0.94). HE4 had high diagnostic efficacy when screening for small cell lung cancer with the highest specificity (0.90, 95% CI 0.77-1.00). CONCLUSIONS: HE4 is a relatively promising and effective biomarker for the diagnosis of lung cancer. Furthermore, given the limitations of our study, additional large-scale and well-designed studies are needed in the future.


Subject(s)
Early Detection of Cancer/methods , Lung Neoplasms/diagnosis , Proteins/analysis , Biomarkers, Tumor/blood , Humans , Odds Ratio , Sensitivity and Specificity , WAP Four-Disulfide Core Domain Protein 2
5.
Anal Chem ; 91(7): 4838-4844, 2019 04 02.
Article in English | MEDLINE | ID: mdl-30864440

ABSTRACT

Remarkable progresses have been made in electrochemical monitoring of living cells based on one-dimensional (1D) or two-dimensional (2D) sensors, but the cells cultured on 2D substrate under these circumstances are departed from their three-dimensional (3D) microenvironments in vivo. Significant advances have been made in developing 3D culture scaffolds to simulate the 3D microenvironment yet most of them are insulated, which greatly restricts their application in electrochemical sensing. Herein, we propose a versatile strategy to endow 3D insulated culture scaffolds with electrochemical performance while granting their biocompatibility through conductive polymer coating. More specifically, 3D polydimethylsiloxane scaffold is uniformly coated by poly(3,4-ethylenedioxythiophene) and further modified by platinum nanoparticles. The integrated 3D device demonstrates desirable biocompatibility for long-term 3D cell culture and excellent electrocatalytic ability for electrochemical sensing. This allows real-time monitoring of reactive oxygen species release from cancer cells induced by a novel potential anticancer drug and reveals its promising application in cancer treatment. This work provides a new idea to construct 3D multifunctional electrochemical sensors, which will be of great significance for physiological and pathological research.


Subject(s)
Cell Culture Techniques , Electrochemical Techniques , Polymers/chemistry , Electric Conductivity , Electrodes , HeLa Cells , Human Umbilical Vein Endothelial Cells/cytology , Humans , MCF-7 Cells
6.
Anal Chem ; 90(2): 1136-1141, 2018 01 16.
Article in English | MEDLINE | ID: mdl-29251916

ABSTRACT

Current achievements on electrochemical monitoring of cells are often gained on two-dimensional (2D) substrates, which fail in mimicking the cellular environments and accurately reproducing the cellular functions within a three-dimensional (3D) tissue. In this regard, 3D scaffold concurrently integrated with the function of cell culture and electrochemical sensing is conceivably a promising platform to monitor cells in real time under their in vivo-like 3D microenvironments. However, it is particularly challenging to construct such a multifunctional scaffold platform. Herein, we developed a 3-aminophenylboronic acid (APBA) functionalized graphene foam (GF) network, which combines the biomimetic property of APBA with the mechanical and electrochemical properties of GF. Hence, the GF network can serve as a 3D scaffold to culture cells for a long period with high viability and simultaneously as an electrode for highly sensitive electrochemical sensing. This allows monitoring of gaseous messengers H2S released from the cells cultured on the 3D scaffold in real time. This work represents considerable progress in fabricating 3D cell culture scaffold with electrochemical properties, thereby facilitating future studies of physiologically relevant processes.


Subject(s)
Aniline Compounds/chemistry , Biomimetic Materials/chemistry , Boronic Acids/chemistry , Cell Culture Techniques/methods , Graphite/chemistry , Tissue Scaffolds/chemistry , Biomimetics , Biosensing Techniques/methods , Cell Adhesion , Cell Proliferation , Electrochemical Techniques/methods , HeLa Cells , Humans , Hydrogen Sulfide/analysis
7.
Oncotarget ; 7(52): 85905-85916, 2016 Dec 27.
Article in English | MEDLINE | ID: mdl-27829234

ABSTRACT

Specificity protein1 (Sp1) is required for TGF-ß-induced epithelial-to-mesenchymal transition (EMT) which has been demonstrated to aggravate the progression of cancer including lung cancer. microRNA-29c (miR-29c) is identified to inhibit EMT, but the correlation between miR-29c and Sp1 in human lung cancer remain incompletely clarified. Here, we confirmed decreased expression of miR-29c and enhanced expression of Sp1 in lung cancer tissues (n = 20) and found that Sp1 could be targeted and inhibited by miR-29c. Besides, the expression of miR-29c was down-regulated in high-metastatic lung cancer cell lines and TGF-ß1-treated cells. The inhibition of miR-29c or overexpression of Sp1 in 95C and A549 cells dramatically enhanced the cell migration and invasion, and also induced the decrease in the expression of epithelial markers, e.g. thyroid transcription factor 1 (TTF-1) and E-cadherin, together with an increase in mesenchymal markers including vimentin, α-smooth muscle actin (α-SMA), which could be restored by overexpression of miR-29c mimics during the TGF-ß-induced EMT. Moreover, dual-luciferase reporter assay was performed and the results indicated that miR-29c/Sp1 could form an auto-regulatory loop with TGF-ß1, which impaired TGFB1 transcription. Furthermore, miR-29c overexpression could abrogate the tumor progression and inhibit the Sp1/TGF-ß expressions in vivo, indicating that miR-29c could be a tumor suppressor and repress the Sp1/TGF-ß axis-induced EMT in lung cancer.


Subject(s)
Lung Neoplasms/pathology , MicroRNAs/physiology , Sp1 Transcription Factor/physiology , Transforming Growth Factor beta1/physiology , Animals , Cell Line, Tumor , Cell Movement , Epithelial-Mesenchymal Transition , Humans , Mice , Neoplasm Invasiveness
8.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 21(1): 105-9, 2013 Feb.
Article in Chinese | MEDLINE | ID: mdl-23484701

ABSTRACT

The aim of this study was to explore the effect of gambogic acid (GA) on MDS SKM-1 cell proliferation, apoptosis and their possible mechanism. Cell proliferation was determined by MTT method. The apoptosis percentage and cell cycle regulation of SKM-1 cells were analyzed by flow cytometry. Morphological features were observed by light microscopy. The mRNA expression of bcl-2 and bax were detected by RT-PCR. The results showed that GA could inhibit the proliferation of SKM-1 cells in a dose- and time-dependent manner (IC50 was 0.37 µg/ml at 48 h), increase the apoptotic percentage of SKM-1 cells, and arrest cell cycle at the G0/G1. The expression of bax mRNA was up-regulated while that of bcl-2 mRNA was down-regulated in SKM-1 cells treated with GA for 48 h. It is concluded that GA can induce apoptosis, which may be related to its effect of arresting cells at phase of G0/G1 and down-regulating bcl-2/bax ratio.


Subject(s)
Cell Proliferation/drug effects , Myelodysplastic Syndromes/pathology , Xanthones/pharmacology , Apoptosis/drug effects , Cell Cycle Checkpoints , Cell Line, Tumor , Humans , Myelodysplastic Syndromes/metabolism , Proto-Oncogene Proteins c-bcl-2/metabolism , bcl-2-Associated X Protein/metabolism
9.
Mol Pharmacol ; 82(5): 958-71, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22909797

ABSTRACT

Tumor necrosis factor-α (TNF-α) is being used as an antineoplastic agent in treatment regimens of patients with locally advanced solid tumors, but TNF-α alone is only marginally active. In clinical use, it is usually combined with other chemical agents to increase its tumor response rate. Our previous studies reported that LYG-202 (5-hydroxy-8-methoxy-7-(4-(4-methylpiperazin-1-yl)butoxy)-2-phenyl-4H-chromen-4-one), a synthesized flavonoid with a piperazine substitution, has antiproliferative, antiangiogenic, and proapoptotic activities in multiple cancer cell lines. Here we evaluated the antineoplastic effect of TNF-α and analyzed the mechanism underlying its combination with LYG-202. Our results indicated that LYG-202 significantly increased the cytostatic and proapoptotic activity of TNF-α in HepG2 cells and heightened the protein level of apoptosis-related genes including caspase-3, caspase-8/9, cleaved poly(ADP-ribose) polymerase, and Bid. The fact that LYG-202 had a fitness score similar to that of the casein kinase 2 (CK2) inhibitor naphthyridine-8-carboxylate (CX-4945) implied to us that it may serve as a potential candidate for CK2 inhibitor, and the kinase activity assay suggested that LYG-202 significantly inhibited CK2 activity. Moreover, the electrophoretic mobility shift assay and luciferase assay showed that LYG-202 blocked the TNF-α-induced nuclear factor-κB (NF-κB) survival signaling pathway primarily by inactivating protein kinase CK2. In murine xenograft models, we also found that LYG-202 enhanced TNF-α antineoplastic activity and inhibited CK2 activity and NF-κB-regulated antiapoptotic gene expression. All these results showed that LYG-202 enhanced TNF-α-induced apoptosis by attenuating the CK2-dependent NF-κB pathway and probably is a promising agent in combination with TNF-α.


Subject(s)
Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Casein Kinase II/physiology , Flavones/pharmacology , NF-kappa B/physiology , Piperazines/pharmacology , Tumor Necrosis Factor-alpha/pharmacology , Active Transport, Cell Nucleus , Animals , Caspases/metabolism , Cell Nucleus/metabolism , Cell Proliferation/drug effects , Drug Synergism , Electrophoretic Mobility Shift Assay , Genes, Reporter , Hep G2 Cells , Humans , I-kappa B Kinase/antagonists & inhibitors , I-kappa B Proteins/metabolism , Luciferases/genetics , Male , Mice , Molecular Docking Simulation , NF-KappaB Inhibitor alpha , NF-kappa B/genetics , Phosphorylation , Signal Transduction , Transcription Factor RelA/metabolism , Transcription, Genetic/drug effects , Xenograft Model Antitumor Assays
10.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 20(2): 252-7, 2012 Apr.
Article in Chinese | MEDLINE | ID: mdl-22541076

ABSTRACT

This study was purposed to investigate the reversal effect of gambogic acid (GA) on multidrug resistance of K562/A02 cells and its mechanism. The IC(50) (half maximal inhibitory concentration) of adriamycin (ADM) was evaluated by MTT. Cell apoptosis was detected by flow cytometry. Morphological changes of K562/A02 cells were observed by fluorescent microscopy with DAPI staining. The expressions of Survivin and P-gp were determined by Western blot. The results showed that the IC(50) of ADM on K562 and K562/A02 cell proliferation were (1.42 ± 0.07) µg/ml and (28.42 ± 1.40) µg/ml respectively. GA ≤ 0.0625 µmol/L had no inhibitory effect on proliferation of K562 and K562/A02. 0.0625 µmol/L GA could enhance the sensitivity of K562/A02 cells to ADM (P < 0.05) and the reversal multiples was 1.53. The apoptotic rate was raised after treating with ADM combined with 0.0625 µmol/L GA for 48 h (P < 0.05). Morphological differences were typical and obvious between cells of control and treated groups under fluorescence microscopy using DAPI staining. After treating K562/A02 cells with ADM combined with 0.0625 µmol/L GA for 48 h, the expressions of Survivin and P-gp were down-regulated at protein levels. It is concluded that GA can enhance the sensitivity of K562/A02 cells to ADM, which may be related to increasing cell apoptosis and down-regulating expressions of Survivin and P-gp.


Subject(s)
Drug Resistance, Multiple/drug effects , Drug Resistance, Neoplasm/drug effects , Xanthones/pharmacology , Apoptosis/drug effects , Doxorubicin/pharmacology , Gene Expression Regulation, Leukemic , Humans , Inhibitor of Apoptosis Proteins/metabolism , K562 Cells , Substance P/metabolism , Survivin
11.
Chin J Cancer Res ; 23(1): 54-8, 2011 Mar.
Article in English | MEDLINE | ID: mdl-23467708

ABSTRACT

OBJECTIVE: To examine the validation and reliability of the distress thermometer (DT) recommended by National Comprehensive Cancer Network (NCCN) in Chinese cancer patients. METHODS: A total of 574 Chinese cancer patients from Beijing Cancer Hospital completed the detection of DT, the Hospital Anxiety and Depression Scale (HADS) and Symptom Checklist 90 (SCL-90), Receiver Operating Characteristic (ROC) curve and Area Under the Curve (AUC) were used to analyze the validation relative to HADS and SCL-90. The patients with DT≥4 and whose distress caused by emotional problems were interviewed with the MiNi International Neuro-psychiatric Interview (MINI) (Chinese Version 5.0). This version was used to analyze cancer patients' psychological and Psychiatric symptoms during the cancer process; 3. Another 106 cancer patients in rehabilitation stage and stable condition were asked to fill in DT two times, at the base time and after 7-10 days. RESULTS: Data of ROC indicates that a DT cutoff score of 4 yielded AUC of 0.80 with a optimal sensitivity (0.80) and specificity (0.70) relative to HADS, and AUC of 0.83 with the greatest sensitivity (0.87) and specificity (0.72) against SCL-90. The DT also has acceptable test-retest reliability (r=0.800, P=0.000); According to the interview results, the most common psychiatric problems cancer patients have adjustment disorder, depression, and anxiety. CONCLUSION: The data suggest that DT has acceptable overall accuracy and reliability as a screening tool for testing distress severity and specific problems causing distress in Chinese cancer patients. It is worth being used in oncology clinic, the rapid screening and interview could help caregivers to identify psychological and psychiatric problems of cancer patients and provide useful information for further treatment.

12.
Biochem Cell Biol ; 87(6): 933-42, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19935879

ABSTRACT

Wogonin, a naturally occurring flavonoid, has been shown to have tumor therapeutic potential both in vitro and in vivo. To better understand its anticancer mechanism, we examined the effect of wogonin on human cervical carcinoma HeLa cells. In this study, we observed that G1 phase arrest was involved in wogonin-induced growth inhibition in HeLa cells. Over a 24 h exposure of HeLa cells to 90 micromol x L(-1) wogonin, the promoters of G1-S transition, including cyclin D1/Cdk4 and pRb, decreased within 12 h and E2F-1 depleted in the nucleus at the same time. As the G1 phase arrest developed, p53 and the Cdk inhibitor p21Cip1 elevated both at protein and mRNA levels. Furthermore, the up-regulation of p21Cip1 induced by wogonin was dramatically inhibited by siRNA-mediated p53 gene silencing. Collectively, our data suggested that wogonin induced G1 phase arrest in HeLa cells by modulating several key G1 regulatory proteins, such as Cdk4 and cyclin D1, as well as up-regulation of a p53-mediated p21Cip1 expression. This mechanism of wogonin may play an important role in the killing of cancerous cells and offer a potential mechanism for its anticancer action in vivo.


Subject(s)
Cyclin D1/antagonists & inhibitors , Cyclin-Dependent Kinase 4/antagonists & inhibitors , Cyclin-Dependent Kinase Inhibitor p21/metabolism , Flavanones/pharmacology , G1 Phase/drug effects , HeLa Cells , Apoptosis/drug effects , Cyclin D1/genetics , Cyclin D1/metabolism , Cyclin-Dependent Kinase 4/genetics , Cyclin-Dependent Kinase 4/metabolism , Cyclin-Dependent Kinase Inhibitor p21/genetics , HeLa Cells/drug effects , HeLa Cells/physiology , Humans , RNA, Small Interfering/genetics , RNA, Small Interfering/metabolism , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/metabolism
13.
Eur J Pharmacol ; 591(1-3): 7-12, 2008 Sep 04.
Article in English | MEDLINE | ID: mdl-18577379

ABSTRACT

Wogonin, a natural monoflavonoid, has been shown to have tumor therapeutic potential in vitro and in vivo. Recently many studies have focused on the induction of apoptosis of tumor cells by wogonin. In this study, we found that wogonin could induce differentiation and G1 phase arrest of human U-937 leukemia cells. The growth of U-937 cells incubated with wogonin was inhibited in a time- and concentration-dependent manner. After treatment with wogonin, U-937 cells exhibited the characteristics of mature granulocytes, such as increased cytoplasmic-to-nuclear ratio, enhanced prominence of cytoplasmic granules, membrane ruffling, a higher NBT-reducing ability, and an increased expression of CD11b. Moreover, wogonin could induce G1 phase arrest and influenced the expression of associated proteins. For example, the expression of phorsphorylated protein kinase C (PKC) delta, p21 increased, while that of cyclin D1/cyclin-dependent kinase (CDK) 4, p-Rb decreased. The upregulation of p21 could be reversed by rottlerin, an inhibitor of PKCdelta. Taken together, wogonin induced U-937 cells to undergo granulocytic differentiation and G1 phase arrest via PKCdelta phosphorylation-induced upregulation of p21 proteins.


Subject(s)
Flavanones/pharmacology , G1 Phase/drug effects , Lymphoma, Large B-Cell, Diffuse/metabolism , Protein Kinase C-delta/drug effects , Cell Differentiation/drug effects , Cyclin-Dependent Kinase Inhibitor p21/drug effects , Cyclin-Dependent Kinase Inhibitor p21/metabolism , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Flavanones/administration & dosage , Humans , Phosphorylation/drug effects , Protein Kinase C-delta/metabolism , Time Factors , U937 Cells , Up-Regulation/drug effects
14.
Cancer Sci ; 99(4): 689-95, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18377421

ABSTRACT

Previous studies have firmly demonstrated that wogonin, a naturally occurring monoflavonoid extracted from the root of the Chinese herb medicine Scutellaria baicalensis, could effectively inhibit the proliferation of several cancer cell lines. However, little is known about the effect of wogonin on differentiation induction of leukemic cells. Here we investigate the potential role of wogonin in the proliferation and differentiation of NB4, a human promyelocytic leukemia cell line derived from a patient with acute promyelocytic leukemia. Our results indicated that wogonin significantly suppressed the proliferation and efficiently induced the differentiation of NB4 cells. NB4 cell growth was inhibited by 55-60% after treatment with 50 microM wogonin for a period of 5 days. The results of the nitroblue tetrazolium (NBT) reduction test (with 67.13% positive cells by 50 microM wogonin for 5 days), Giemsa staining (with 67.24% positive cells by 50 microM wogonin for 5 days), and the expression of mature-related cell-surface differentiation antigens CD11b and CD14 (with 70.94% CD11b(+) and 5.82% CD14(+) cells by 50 microM wogonin for 5 days) demonstrated an increase in the differentiation-inducing action of wogonin on the NB4 cells, which was accompanied by an increase in mRNA and protein expression of phospholipids scramblase 1 (PLSCR1). Meanwhile, the level of phosphorylated PKC delta (Ser643) was dramatically increased in wogonin treated NB4 cells. Interestingly, wogonin treatment displayed little effect on the apoptosis of NB4 cells. Taken together, the results reported here demonstrated that wogonin could promote the granulocytic differentiation of NB4 cells by up-regulating the expression of PLSCR1 gene.


Subject(s)
Antineoplastic Agents/pharmacology , Flavanones/pharmacology , Gene Expression/drug effects , Granulocytes/drug effects , Leukemia, Promyelocytic, Acute/immunology , Phospholipid Transfer Proteins/genetics , Antineoplastic Agents/chemistry , CD11b Antigen/analysis , Cell Differentiation/drug effects , Cell Differentiation/genetics , Cell Line, Tumor , Cell Proliferation/drug effects , Flavanones/chemistry , Granulocytes/immunology , Humans , Lipopolysaccharide Receptors/analysis , Phospholipid Transfer Proteins/antagonists & inhibitors , RNA Interference
15.
Carcinogenesis ; 28(3): 632-8, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17012222

ABSTRACT

Molecular mechanisms of cell-cycle arrest caused by gambogic acid (GA), a natural product isolated from the gamboge resin of Garcinia hanburryi tree, have been investigated using BGC-823 human gastric carcinoma cells as a model. Based on our 3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyltetrazoliumbromide (MTT) assay and flow cytometric analysis, treatment of BGC-823 cells with growth suppressive concentrations of GA caused an irreversible arrest in the G(2)/M phase of the cell cycle. Western blot analysis demonstrated that GA-induced cell-cycle arrest in BGC-823 cells was associated with a significant decrease in CDC2/p34 synthesis, which led to the accumulation of phosphorylated-Tyr(15) (inactive) form of CDC2/p34. Real-time PCR, western blot and kinase activity assays revealed that GA-induced reduction of CDC2/p34 expression was mediated through the inhibition of cyclin-dependent kinase (CDK)-activating kinase (CDK7/cyclin H) activity. In addition, GA-treated cells were shown to have a low level of CDK7 kinase-phosphorylated-Thr(161) CDC2/p34 (active). Taken together, our results suggested that the inhibited proliferation of GA-treated BGC-823 cells was associated with the decreased production of CDK7 mRNA and protein, which in turn, resulted in the reduction of CDK7 kinase activity. The reduced CDK7 kinase activity is responsible for the inactivation of CDC2/p34 kinase and the irreversible G(2)/M phase cell-cycle arrest of human gastric carcinoma BGC-823 cells.


Subject(s)
CDC2 Protein Kinase/metabolism , Cell Division/drug effects , Cyclin-Dependent Kinases/metabolism , G2 Phase/drug effects , Stomach Neoplasms/pathology , Xanthones/pharmacology , Cell Line, Tumor , Cyclin B/metabolism , Cyclin B1 , Dose-Response Relationship, Drug , Humans , Kinetics , Phosphorylation , Cyclin-Dependent Kinase-Activating Kinase
16.
Cancer Chemother Pharmacol ; 58(4): 434-43, 2006 Oct.
Article in English | MEDLINE | ID: mdl-16470410

ABSTRACT

OBJECTIVES: To investigate the effects and potential mechanisms of gambogic acid (GA), a naturally occurring anticancer agent, on the expression and regulation of telomerase in human gastric carcinoma cells. METHODS: GA-induced inhibition of cell proliferation was evaluated by the commonly employed MTT assay on two human gastric carcinoma cell lines, MGC-803 and SGC-7901. Telomerase activity and hTERT mRNA expression were determined by telomeric repeat amplication protocol-polymerase chain reaction and reverse transcription-polymerase chain reaction, respectively. The hTERT promoter activity was measured by luciferase assay. The expression of c-MYC, an apoptotic gene that modulates the expression of hTERT promoter, was quantified by Western blotting. RESULTS: The proliferation of human gastric carcinoma cell lines, MGC-803 and SGC-7901, was significantly inhibited with GA treatment. Both telomerase activity and hTERT mRNA expression were notably decreased in cells treated with GA. The activity of hTERT promoter and the expression of c-MYC were also remarkably decreased in GA-treated cells. CONCLUSION: This study demonstrated that GA treatment of human gastric carcinoma cell lines, MGC-803 and SGC-7901, significantly reduced the expression of c-MYC in a time- and concentration-dependent manner accompanied with the down-regulation of the hTERT transcription and the ultimate reduction in telomerase activity. Our results indicate that the hTERT is a target of c-MYC activity and identify a feasible mechanism of GA's potent anticancer activity.


Subject(s)
DNA-Binding Proteins/drug effects , Peptide Fragments/drug effects , Telomerase/drug effects , Xanthones/pharmacology , Cell Line, Tumor , DNA-Binding Proteins/metabolism , Down-Regulation , Enzyme-Linked Immunosorbent Assay , Humans , Peptide Fragments/metabolism , RNA, Messenger , Stomach Neoplasms/enzymology , Telomerase/metabolism , Transcription Factors/drug effects , Transcription Factors/metabolism
17.
World J Gastroenterol ; 9(11): 2441-4, 2003 Nov.
Article in English | MEDLINE | ID: mdl-14606072

ABSTRACT

AIM: To investigate the inhibitory effect of serum preparation from rabbits orally administered cobra venom (SRCV) on implanted hepatocellular carcinoma (HCC) cells in mice. METHODS: An HCC cell line, HepA, was injected into mice to prepare implanted tumors. The animals (n=30) were divided randomly into SRCV, 5-fluorouracil (5-FU), and distilled water (control) groups. From the second day after transplantation, 20 mg/kg 5-FU was administered intraperitoneally once a day for 9 days. SRCV (1,000 mg/kg) or distilled water (0.2 mL) was given by gastrogavage. Tumor growth inhibition was described by the inhibitory rate (IR). Apoptosis was detected by transmission electron microscopy (TEM), flow cytometry (FCM), and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL). Student's t-test was performed for statistical analysis. RESULTS: The tumor growth was inhibited markedly by SRCV treatment compared to that in the control group (P<0.01). The treatment resulted in a significant increase in the apoptotic rate of cancer cells by the factors of 10.5+/-2.4 % and 20.65+/-3.2 % as demonstrated through TUNEL and FCM assays, respectively (P<0.01). The apoptotic cells were also identified by characteristic ultrastructural features. CONCLUSION: SRCV can inhibit the growth of implanted HepA cells in mice, and the apoptosis rate appears to elevate during the process.


Subject(s)
Blood Proteins/pharmacology , Carcinoma, Hepatocellular/drug therapy , Elapid Venoms/blood , Liver Neoplasms, Experimental/drug therapy , Animals , Apoptosis/drug effects , Carcinoma, Hepatocellular/pathology , Cell Division/drug effects , Cell Line, Tumor/transplantation , Female , Liver Neoplasms, Experimental/pathology , Mice , Mice, Inbred Strains , Neoplasm Transplantation , Rabbits
18.
Acta Pharmacol Sin ; 24(10): 1045-50, 2003 Oct.
Article in English | MEDLINE | ID: mdl-14531950

ABSTRACT

AIM: To investigate whether nimesulide could suppress tumor growth and induce apoptosis in implanted hepatoma mice and to explore the molecular mechanisms. METHODS: Male mice received nimesulide 10 mg/kg, 20 mg/kg, and 40 mg/kg ig daily for 21 d. Electron microscopy (EM), flow cytometry (FCM), DNA ladder, radioimmunoassay (RIA), and Western blot analysis were employed to investigate effect of nimesulide on mice hepatoma and the related molecular mechanisms. RESULTS: Nimesulide inhibited the growth of hepatoma (from 14 % to 62 %) and elicited typical apoptotic morphologic changes. The DNA ladder of high dose nimesulide was more clearly observed and apoptotic rate was 51.3 %+/-1.5 %. Nimesulide also decreased cyclooxygenase-2 (COX-2), prostaglandin E2 (PGE2) and Bcl-2 expression, while increased the level of Bax protein. CONCLUSION: Nimesulide suppresses tumor growth and induces apoptosis by inhibiting COX-2 and PGE2 expression, which may be related to overexpression of Bax over Bcl-2.


Subject(s)
Apoptosis/drug effects , Liver Neoplasms, Experimental/pathology , Proto-Oncogene Proteins c-bcl-2/metabolism , Proto-Oncogene Proteins/metabolism , Sulfonamides/pharmacology , Animals , Cyclooxygenase 2 , Cyclooxygenase 2 Inhibitors , Cyclooxygenase Inhibitors/pharmacology , Dinoprostone/metabolism , Isoenzymes/metabolism , Liver Neoplasms, Experimental/metabolism , Male , Mice , Neoplasm Transplantation , Prostaglandin-Endoperoxide Synthases/metabolism , Random Allocation , Tumor Cells, Cultured , bcl-2-Associated X Protein
19.
Acta Pharmacol Sin ; 23(7): 631-7, 2002 Jul.
Article in English | MEDLINE | ID: mdl-12100758

ABSTRACT

AIM: To investigate whether JTE-522 [4-(4-cyclohexyl-2-methyloxazol-5-yl)-2-fluorobenzenesulfonamide], a selective COX-2 inhibitor, can induce apoptosis and inhibit cell proliferation in human endometrial cancer cell line RL95-2 cells and to explore the molecular mechanisms. METHODS: [3-(4,5)-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT), DNA ladder, enzyme-linked immunosorbent assay (ELISA), flow cytometry, RT-PCR, and Western blot analysis were employed to investigate effect of JTE-522 on human endometrial cancer cell line RL95-2 cells and the related molecular mechanisms. RESULTS: JTE-522 inhibited the growth of RL95-2 cells and induced the apoptosis. Furthermore, it arrested G0/G1 phase and inhibited S phase in RL95-2 cells. JTE-522 inhibited the expressions of COX-2 mRNA, phosphorylated Rb, and CDK4 proteins, while increased the levels of p53, p21, cyclin D1 proteins, and the activity of caspase-3 in RL95-2 cells. CONCLUSION: JTE-522 inhibits cell proliferation and induces apoptosis in RL95-2 cells, which may be associated with the activation of caspase-3-like proteases, down-regulation of the expression of COX-2 mRNA, phosphorylated Rb, and CDK4 proteins, and up-regulation of the expressions of p53, p21, and cyclin D1 proteins.


Subject(s)
Apoptosis/drug effects , Benzenesulfonates/pharmacology , Endometrial Neoplasms/pathology , Isoenzymes/antagonists & inhibitors , Oxazoles/pharmacology , Caspase 3 , Caspases/metabolism , Cell Division/drug effects , Cell Line, Tumor , Cyclooxygenase 2 , Endometrial Neoplasms/metabolism , Female , Humans , Isoenzymes/biosynthesis , Isoenzymes/genetics , Membrane Proteins , Prostaglandin-Endoperoxide Synthases/biosynthesis , Prostaglandin-Endoperoxide Synthases/genetics , RNA, Messenger/genetics
20.
World J Gastroenterol ; 8(3): 431-5, 2002 Jun.
Article in English | MEDLINE | ID: mdl-12046064

ABSTRACT

AIM: To identify whether JTE-522 can induce apoptosis in AGS cells and ROS also involved in the process, and to investigate the changes in NF-kB, p53, bcl-2 and caspase in the apoptosis process. METHODS: Cell culture, MTT, Electromicroscopy, agarose gel electrophoresis, lucigenin, Western blot and electrophoretic mobility shift assay (EMSA) analysis were employed to investigate the effect of JTE-522 on cell proliferation and apoptosis in AGS cells and related molecular mechanisms. RESULTS: JTE-522 inhibited the growth of AGS cells and induced the apoptosis. Lucigenin assay showed the generation of ROS in cells under incubation with JTE-522. The increased ROS generation might contribute to the induction of AGS cells to apoptosis. EMSA and Western blot revealed that NF-kB activity was almost completely inhibited by preventing the degradation of IkBalpha. Additionally, by using Western blot we confirmed that the level of bcl-2 was decreased, whereas p53 showed a great increase following JTE-522 treatment. Their changes were in a dose-dependent manner. CONCLUSION: These findings suggest that reactive oxygen species, NF-kB, p53, bcl-2 and caspase-3 may play an important role in the induction of apoptosis in AGS cells after treatment with JTE-522.


Subject(s)
Adenocarcinoma/metabolism , I-kappa B Proteins , Stomach Neoplasms/metabolism , Adenocarcinoma/pathology , Apoptosis/drug effects , Benzenesulfonates/pharmacology , Caspases/metabolism , Cell Division/drug effects , DNA-Binding Proteins/metabolism , Humans , NF-KappaB Inhibitor alpha , NF-kappa B/metabolism , Oxazoles/pharmacology , Proto-Oncogene Proteins c-bcl-2/metabolism , Reactive Oxygen Species/metabolism , Stomach Neoplasms/pathology , Tumor Cells, Cultured , Tumor Suppressor Protein p53/metabolism
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