Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:A9QXG9 (bcl-2)
 7,497 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Poor treatment results in advanced hepatoblastoma (HB) made alternative treatment approaches desirable. Gene-directed tumor therapy is increasingly investigated in different malignancies. The aim of this study was to analyze possible alternatives of gene transfer into HB cells and to study therapeutic applications based on different strategies. Liposomal transfection of HB cells was assessed using liver-specific promoters, and adenovirus and Sendai virus transductions were performed in vitro. Transfer efficiencies were measured via flow cytometry determining expression of vector-encoded marker gene green fluorescent protein. Gene silencing of the anti-apoptotic bcl-2 gene in HUH6 cells was performed using lipofection of small interfering RNA (siRNA). Additionally, suicide gene therapy was carried out through a yeast-derived cytosine deaminase (YCD)-combined yeast uracil phosphoribosyltransferase (YUPRT)-based adenovirus-mediated gene transfer, leading to a potent intracellular prodrug transformation of 5-fluorocytosine into 5-fluorouracil. Treatment efficiencies were monitored via MTT viability assay. Highest gene transfer rates (86%) were observed using adenovirus transduction. We furthermore observed a significant therapeutic effect of adenovirus-mediated YCD::YUPRT suicide gene transfer. Liposomal-mediated anti-bcl-2 siRNA transfer led to a significant improvement of cisplatin treatment in HUH6 cells. Liver-specific promoters were found to be strongly active in HUH6 cells (mixed HB-derived), but less active in HepT1 cells (embryonal HB-derived). Liposomal transfection and viral transduction are effective approaches to genetically manipulate HB cells in vitro. For the first time, we demonstrate a positive effect of siRNA gene silencing in this malignancy. Additionally, we successfully investigated a model of adenovirus-based suicide gene therapy in HB cell cultures. Our data strongly encourage further studies assessing these alternative treatment approaches.
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PMID:In vitro gene targeting in human hepatoblastoma. 1637 44

To evaluate the feasibility of gene therapy using bcl-2 as target in multiple drug resistance of leukemia, the small interfering RNA eukaryotic expression vector specific to human bcl-2 gene was constructed by gene recombination, then transfected into HL-60/VCR cells. Stable transfectants were obtained by G418 screening. The growth curve and drug sensitivity were detected by using MTT. The expression of Bax and ZNRD1 was analyzed by Western blot. The results showed that mU6pro-bcl-2 siRNA was successfully constructed and transfected into HL-60/VCR cells. The IC(50) of transfected cells to vincristine and adriamycin was significantly reduced as compared with that of the control. The expression of ZNRD1 in transfected cells was decreased as compared with that of the control, while Bax not. It is concluded that the bcl-2 siRNA restores the sensitivity of HL-60/VCR cells to conventional chemotherapeutic agents to a certain degree.
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PMID:[Reversion of multidrug resistance in HL-60/VCR cells by down-regulation of bcl-2 with bcl-2 siRNA]. 1640 69

To study the effects and possible mechanism of Vitamin K(2) (VK(2)) in the treatment of MDS-JSN04 cells, the changes of morphologic features of MDS-JSN04 cells were investigated by cytomorphology, the apoptosis of MDS-JSN04 cells was observed by transmission electron microscope; cellular proliferation was determined by the MTT assay; cell apoptosis, cell cycle shift and expression of myeloid-specific differentiation antigen (CD11b, CD13) were analyzed by flow cytometry (FCM). The expression of apoptosis-related genes bcl-2, survivin and bax were detected by retrotranscriptase polymerase chain reaction (RT-PCR); the activity of caspase-3 was determined by chemiluminescence assay. The results showed that the typical apoptotic morphological features appeared in cells treated with VK(2) for 72 hours; VK(2) induced apoptosis of MDS-JSN04 cells and in a dose-and-time-dependent manner, G(0)/G(1) cell arrest and significantly down-regulated the expression of bcl-2 and survivin, but had no effect on the expression of bax; the activity of caspase-3 significantly increased. It is concluded that VK(2) induces apoptosis of MDS-JSN04 cells through activating caspase-3 pathways and the apoptosis-related genes bcl-2, survivin may play an important role in this process.
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PMID:[Inhibition effect of vitamin K2 on human MDS-JSN04 cell line and its possible mechanism]. 1640 73

Bcl-2 is best known for its anti-apoptotic function in a wide variety of cell types. The objective of this study was to investigate the effects of bcl-2 on the types of cell demise in the HeLa/bcl-2 cells induced by H2O2. The HeLa cell expressed stably bcl-2 was established and defined as the HeLa/bcl-2 cell strain, while the cell transfected with the empty expression vector was defined as the HeLa/vector cell strain. MTT assay revealed that the HeLa/bcl-2 cells showed a shorter life span. BrdU incorporation assay indicated that the bcl-2 exerted anti-demise effect on the HeLa/bcl-2 cells at the low concentration of H2O2. However, at the high concentration of H2O2, the death of the HeLa/bcl-2 cells was more than that of the HeLa/vector cells. The flow cytometry demonstrated that H2O2 mainly induced apoptosis in the HeLa/vector cells and elicited necrosis in the HeLa/bcl-2 cells. The addition of celecoxib to the cells treated by H2O2 could increase apoptosis in the HeLa/vector cells and convert necrosis into apoptosis in the HeLa/bcl-2 cells. The higher levels of cellular free radical and GSH were found in the HeLa/bcl-2 cells, but not in the HeLa/vector cells. With 200 microM H2O2 challenge for 48 h, the level of the cellular free radical was increased in the both strains, while the level of the GSH was decreased in the both strains. Celecoxib could reverse the difference between the both strains led by H2O2. Western blotting showed that the expression of COX-2 was always higher in the HeLa/bcl-2 cells than in the HeLa/vector cells under the both of treated and untreated with H2O2, while the level of COX-1 was relative stable in the both strains. These results suggested that the crosstalk between the bcl-2 and the COX-2 pathways could exist, the bcl-2 might up-regulate COX-2 to modify sensitivity to the types of demise in the HeLa/bcl-2 cell.
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PMID:Bcl-2 switches the type of demise from apoptosis to necrosis via cyclooxygenase-2 upregulation in HeLa cell induced by hydrogen peroxide. 1645 14

C-myc is an oncogene with the important role of cell proliferation controller. It has been found to be amplified and overexpressed in osteosarcoma. Moreover, it can promote cell transformation and induce metastatic features. Some studies showed that overexpression of c-myc could induce resistance in response to antineoplastic agents. Currently, we constructed the recombinant adenovirus (Ad-Asc-myc) encoding antisense c-myc fragment and investigated its effect on the in vitro sensitivity of osteosarcoma MG-63 cells to cisplatin(CDDP). The osteosarcoma MG-63 cells were transfected by the Ad-Asc-myc in vitro, and Western Blot, MTT assay, RT-PCR, flow cytometry (FCM), and transmission electron microscopy (TEM) were used to study expression of c-myc and caspase-3 protein, tumor cell proliferation in vitro, cell apoptotic morphology and cell cycle change. Ad-Asc-myc encoding antisense c-myc fragment was obtained with the titer of 2.0 x 10(9) pfu/ml. Ad-Asc-myc downregulated the expression of c-myc protein after transfected MG-63 cells for 48 hours, combined with the treatment of 2.0, 5.0 microg/ml cisplatin for 2 hours can inhibited tumor cells proliferation in vitro by 33.4 and 54.2 percent, respectively, which had significant difference compared with control recombinant adenovirus (Ad-LacZ) groups (P < 0.05). RT-PCR revealed that Ad-Asc-myc downregulated expression of bcl-2 and upregulated expression of Bax, and no appreciable changes were observed in the expression of E2F-1. Detection of caspase-3 protein TEM, and FCM analysis showed that Ad-Asc-myc could induce apoptosis of transfected cells, which was enhanced by the treatment of cisplatin. Cell cycle analysis showed that obvious G(2)/M phase arrested in transfected cells. In conclusion, Ad-Asc-myc increased the in vitro sensitivity of osteosarcoma MG-63 cells to cisplatin as well as induced apoptosis.
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PMID:Recombinant antisense C-myc adenovirus increase in vitro sensitivity of osteosarcoma MG-63 cells to cisplatin. 1646 85

The aim of this study was to investigate the inhibition effect of arsenic sulfide (As2S2) on the growth of in vitro cultured BMMNC from MDS patients and to explore its possible cellular and molecular mechanisms. The apoptosis of MDS cells induced by As2S2 solution of different concentrations were studied with MTT, flow cytometry, and RT-PCR. The results showed that (1) low concentration of As2S2 (0-0.6 mg/L) had no marked inhibition effect on proliferation of MDS cells; (2) after treatment with 1.5-50 mg/L of As2S2, both low risk MDS cells and high risk MDS cells presented typical features of apoptosis with a dose-dependent manner, the expression of bcl-2 mRNA and the ratio of bcl-2/bax obviously decreased after As2S2 treatment (P < 0.05); (3) BMMNC from MDS patients had higher apoptosis ratio than that of BMMNC from control. It is concluded that BMMNC excessive apoptosis exists in MDS patients; low concentration of As2S2 (0-0.6 mg/L) shows no inhibition effect on proliferation of MDS cells; high concentration of As2S2 (1.5-50 mg/L) induces apoptosis of MDS cells.
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PMID:[Apoptosis of in vitro cultured BMMNC from MDS patients induced by arsenic sulfide]. 1663 96

Our previous studies have shown that atRA treatment resulted in cell-cycle block and growth inhibition in mouse embryonic palatal mesenchymal (MEPM). In the current study, gestation day (GD) 13 MEPM cells were used to test the hypothesis that the growth inhibition by atRA is due to apoptosis. The effects of atRA on apoptosis were assessed by performing MTT assay, Cell Death Detection ELISA and flow cytometry, respectively. Data analysis confirmed that atRA treatment induced apoptosis-like cell death, as shown by decreased cell viability and increased fragmented DNA and sub-G1 fraction. atRA-induced apoptosis was associated with upregulation of bcl-2, translocation of bax protein to the mitochondria from the cytosol, activation of caspase-3 and cytochrome c release into cytosol. atRA-induced apoptosis was abrogated by z-DEVD-fmk, a caspase-3 specific inhibitor, and z-VAD-fmk, a general caspase inhibitor, suggesting that the atRA-induced cell death of MEPM cells occurs through the cytochrome c- and caspase-3-dependent pathways. In addition, atRA treatment caused a strong and sustained activation of c-Jun N-terminal kinase (JNK) and p38 kinase (p38), as well as an early but transient activation of extracellular signal-regulated kinase (ERK). Importantly, atRA-induced DNA fragmentation and capase-3 activation were prevented by pretreatment with the JNK inhibitor (SP600125) and the p38 MAPK inhibitor (SB202190), but not by pretreatment with MEK inhibitor (U0126). From these results, we suggest that mitogen-activated protein kinase-dependent pathways is involved in the atRA-induced apoptosis of MEPM cells.
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PMID:atRA-induced apoptosis of mouse embryonic palate mesenchymal cells involves activation of MAPK pathway. 1671 91

The anticancer effects of wogonin on murine sarcoma S180 both in vitro and in vivo were investigated, and its pro-apoptotic molecular mechanism was further studied. Wogonin treatment resulted in significant inhibition of S180 cells in a concentration-dependent manner detected by MTT assay. The IC50 value for 48 h was (7.37+/-1.53) x 10(-5) M. Typical morphological changes and apoptosis bleb phenomenon in S180 cells exposed to wogonin were distinctly observed by the inverted light microscope and the fluorescence microscope, respectively. According to protocols of transplanted tumor research, mice were transplanted with tumor cells S180. The weight of tumor and the peripheral leucocyte count were observed after the treatment of wogonin. The significant suppression of tumor growth was observed, and the peripheral leucocyte count of S180-bearing mice remained no significant changes compared with control group. After the treatment of 40 mg/kg wogonin, the inhibitory rate of tumor weight was 53.01%. Additional DNA fragmentation assay showed that wogonin induced apoptosis on murine sarcoma S180 tissue. RT-PCR results indicated that the increasing mRNA levels of bax and p53 and the decreasing mRNA level of bcl-2 were induced by wogonin. Western-blot assay showed that the increasing protein level of bax and the decreasing protein level of bcl-2 were induced by wogonin. Collectively, wogonin could induce apoptosis in murine sarcoma S180 thereby inhibiting the tumor growth both in vitro and in vivo. The pro-apoptotic effects might be related to the improvement of mRNA level of p53, the improvement of mRNA and protein levels of bax, and the reduction of mRNA and protein levels of bcl-2.
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PMID:The anticancer activities of wogonin in murine sarcoma S180 both in vitro and in vivo. 1675 5

Although the recently-developed Gemcitabine (GEM) has renewed interest in clinical research in pancreatic carcinoma, it offers modest improvement of tumor-related symptoms and marginal survival advantage, even when combined with other currently-available chemotherapeutic agents such as 5-Fluorouracil (5-FU). We hypothesized that this disappointing result could be due to an interaction between the two drugs affecting cytotoxic activity. We measured in-vitro growth inhibition, cell cycle distribution, gene and protein expression of apoptosis regulators bcl-2, bcl-x and survivin, NFkappaB and telomerase activities of human pancreatic carcinoma cell line Capan-2 following exposure to GEM and 5-FU singly or combined, by MTT assay and median effect analysis, flow cytometry, real-time RT-PCR, Western blotting, electrophoretic mobility shift assay (EMSA) and telomeric repeat amplification protocol (TRAP) assay, respectively. We found cell growth to be inhibited by both drugs, decreasing the percentage of cells in S and G2/M phases and inducing apoptosis, dependent on the levels of bcl-2, bcl-xL and survivin expression in the case of 5-FU, but not for GEM. Moreover, while telomerase activity was reduced equally by both drugs, 5-FU but not GEM effectively downregulated NFkappaB binding activity. Intriguingly, a substantial antagonistic effect was noticed when GEM was combined with 5-FU in the concentration range tested, with the exception of the TRAP assay. These indications of an antagonistic interaction between GEM and 5-FU in some pancreatic cancer context urge further investigation of both genetic and non-genetic differences to identify the variables most relevant for optimal selection and dosing of treatment for the individual patient.
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PMID:Antagonistic interactions between gemcitabine and 5-fluorouracil in the human pancreatic carcinoma cell line Capan-2. 1717 10

Tanshinone IIA, a diterpene quinone extracted from the traditional herbal medicine, Salvia miltiorrhiza Bunge, is used widely and successfully in clinics in China for treating inflammatory diseases. Recently tanshinone IIA has been reported to have apoptosis inducing effects on a large variety of cancer cells. In this study, the anti-proliferation and apoptosis inducing effects of tanshinone IIA as well as its influence on cell adhesion to and invasion through the extracellular matrix (ECM) on acute promyelocytic leukemia (APL) NB4 cells in vitro were studied. Cell proliferation was assessed by MTT assay, cell apoptosis was observed by Hoechst 33258 staining and flow cytometry (FCM); The variation of caspase-3 and apoptotic related genes were assayed by Western blotting, cell mitochondrial membrane potential as well as cell adhesive and invasive effects were also investigated by using standard methods. The results showed that tanshinone IIA exhibited induction of apoptosis by activation of caspase-3, downregulation of anti-apoptotic protein bcl-2 and bcl-xl and upregulation of pro-apoptotic protein bax, as well as disruption of the mitochondrial membrane potential. Furthermore, treatment by tanshinone IIA could reduce cell adhesion to and invasion through ECM in leukemia NB4 cells. These data provide a potential mechanism for tanshinone IIA-induced apoptosis and cell growth inhibition in leukemia NB4 cells, suggesting that tanshinone IIA may serve as an effective adjunctive reagent for the treatment of APL.
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PMID:Induction of apoptosis and inhibition of cell adhesive and invasive effects by tanshinone IIA in acute promyelocytic leukemia cells in vitro. 1695 48


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