OBJECTIVE: To investigate the effect of human papillomavirus types 16E6 on the sensitivity of chemotherapy for cervical carcinoma in different p53 genotype cell lines. METHODS: The apoptosis rates of each group were detected by AO/EB, immunofluorescence and Annexin V/PI stained methods. The expressions of protein HPV16E6 and p53(mt) after the treatments of different concentration of DDP were detected by Western blot. HPV16E6 mRNA in C33A, C33A-E6, C33A-P, and CaSki cell lines under different DDP treatments were detected by RT-PCR. RESULTS: AO/EB and Annexin V/PI stained tests showed that the apoptosis rates of C33A, C33A-E6, C33A-P, and CaSki cells were significantly increased when DDP concentration increased. Western blot showed that the HPV16E6 protein could be detected only in C33A-E6 and CaSki cell lines. The expression of HPV16E6 protein in C33A-E6 and CaSki cell lines gradually decreased and was hardly detected with increased dosage of DDP and the prolonged treatment time (P<0.01), and slightly increased in C33A-E6 and Caski cell lines without the treatment, but there was no significant difference between them (P>0.05). Protein p53(mt) persistently expressed in C33A-E6, C33A, and C33A-P cell lines following the increased dosage of DDP and the prolonged treatment time(P>0.05), while it couldn't be found in CaSki cell line. RT-PCR showed that without DDP intervention, there was no significant difference of HPV16E6 mRNA in C33A-E6 and CaSki cell lines within 24 h.The HPV16E6 mRNA in C33A-E6 cell line expressed much higher than that in CaSki (P<0.05), and HPV16E6 mRNA of 2 cell lines expressed much higher at 48 h than at 24 h (P<0.05).The expression of HPV16E6 mRNA in C33A-E6 and CaSki cell lines gradually decreased with the increased DDP and prolonged treatment time (P<0.01), while there was no significant difference between C33A-E6 and CaSki cell lines under the same DDP concentration (P>0.05). CONCLUSION Effect of HPV16E6 on the sensitivity of chemotherapy for cervical carcinoma cell lines is not markedly related with the different p53 genotype forms(p53(mt)/p53wt ). HPV16E6 may affect the proliferation and sensitivity of chemotherapy in C33A cell line through other mechanism.
Antineoplastic Agents ; pharmacology ; Apoptosis ; genetics ; Cell Line, Tumor ; Cisplatin ; pharmacology ; Female ; Genotype ; Human papillomavirus 16 ; genetics ; Humans ; Oncogene Proteins, Viral ; biosynthesis ; genetics ; Papillomavirus Infections ; virology ; Repressor Proteins ; biosynthesis ; genetics ; Tumor Suppressor Protein p53 ; biosynthesis ; genetics ; Uterine Cervical Neoplasms ; pathology ; virology

OBJECTIVETo investigate the effect of ERCC1 gene on the repair capability of damaged DNA in lung cancer A549 cells induced by benzo[a]pyrene.

METHODSRecombinant plasmid expressing ERCC1 antisense RNA was constructed and transfected into A549 cells by Lipofectin reagent. The stable-transfected cell colonies were selected by hygromycin. Cell viability was determined by the MTT assay. The level of ERCC1 mRNA was measured by Northern Blot analysis. Single cell gel electrophoresis assay was applied to determine the cellular DNA damage and fifty cells for each group were counted.

RESULTSSeven positive colonies expressing ERCC1 antisense RNA were screened. There was no growth rate difference between the antisense-transfected cells and the parental cells. The endogenous mRNA level in transfected colonies decreased in varied degrees, i.e. 12% approximately 86% of that of the parental cells in Northern Blot assay. After 24 h treatment of 10 micro mol/l benzo[a]pyrene, the repair capability for DNA damage in transfected colonies was reduced to 29% approximately 71% of that of the parental cells. Also, a statistically significant correlation was observed between expression of ERCC1 mRNA and repair capability (r = 0.84).

CONCLUSIONAntisense ERCC1 RNA decreased the repair capability for damaged DNA in lung cancer cells induced by benzo[a]pyrene.

Benzo(a)pyrene ; toxicity ; Cell Line, Tumor ; DNA Damage ; drug effects ; DNA Repair ; drug effects ; DNA-Binding Proteins ; genetics ; metabolism ; pharmacology ; Endonucleases ; genetics ; metabolism ; pharmacology ; Humans ; Lung Neoplasms ; pathology ; Plasmids ; RNA, Antisense ; pharmacology ; RNA, Messenger ; metabolism ; Repressor Proteins ; Transfection

OBJECTIVETo study the growth-inhibitory and apoptosis-inducing effects of realgar nanometer suspension in human carcinoma cervical cell Siha line, and the effect on HPV16E6/E7 oncogene expression.

METHODA " micro-jet efflux" strategy was used for the preparation of realgar nanometer suspension. Siha cells were treated with various concentrations (6.25, 12.5, 25, 50 mg x L(-1)) of realgar nanometer suspension for different hours (12, 24, 48, 72 h). The effect of realgar nanometer suspension on Siha cell growth suppression was detected by MTT method. Special morphological changes of apoptosis were observed by light and transmission electron microscopy (TEM) and DNA fragments electrophoresis. The apoptotic rates were quantified by flow cytometry (FCM). The expression of HPV16E6/E7 mRNA was assayed by RT-PCR.

RESULTAfter being treated with 25-50 mg x L(-1) realgar nanometer suspension for 48, 72 h, the survival of Siha cells decreased, and the rate of apoptosis markedly increased. With TEM and DNA electrophoresis, the special morphological changes were found. The apoptotic rates of Siha cells treated with realgar nanometer suspension were significantly higher than those in the control group (P < 0.01). G0-G1 phase arrest appeared following the treatment with realgar nanometer suspension in 25 and 50 mg x L(-1) 48 h. RT-PCR assay revealed that realgar nanometer suspension reduced HPV16E6/E7 gene expression.

CONCLUSIONRealgar nanometer suspension can inhibit the proliferation of human carcinoma cervical cell Siha line and induce the cell apoptosis. The mechanism may be related to the down-regulation of HPV16E6/E7 oncogene expression.

Apoptosis ; drug effects ; Arsenicals ; pharmacology ; Cell Line, Tumor ; Flow Cytometry ; Gene Expression ; drug effects ; Humans ; Microscopy, Electron, Transmission ; Oncogene Proteins, Viral ; genetics ; Papillomavirus E7 Proteins ; Repressor Proteins ; genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Sulfides ; pharmacology

OBJECTIVETo evaluate the inhibitory effects of survivin antisense oligonucleotide (survivin-ASODN) mediated by polyamidoamine dendrimer (PAMAM) against the growth of subcutaneously transplanted colorectal cancer in nude mice.

METHODSNude mouse models bearing colorectal cancer was established by subcutaneous injection of SW620 cells. Survivin- OSADN (300 microg/L) was mixed with 4.06 microg/L PAMAM or liposome to prepare two transfection complexes, and their morphologies were observed by transmission electron microscope. The particle size of the prepared complexes was determined by laser particle size analyzer, and the zeta potential was measured. The encapsulation efficiency and the DNA release rate in vitro were determined by ultraviolet spectrophotometer. The transfection complexes were then directly injected into the xenografts of the tumor-bearing nude mice. The tumor volume changes were observed, and the expression of survivin in the transplanted tumor was measured by Western blotting.

RESULTSThe PAMAM-survivin-ASODN complex had a significantly smaller diameter and greater zeta potential than liposome-survivin-ASODN (P<0.01 and 0.05, respectively). The encapsulation efficiency was comparable between the two complexes. In in vitro condition, PAMAM-survivin-ASODN allowed sustained survivin-ASODN release for as long as 14 days, as compared with the 5 days for the liposome complex. After injection into the tumor xenografts, PAMAM-survivin- ASODN resulted in significantly lower expression of survivin protein in the transplanted tumors (P<0.05), and also in significantly greater reduction of the tumor volume than the liposome complex (P<0.05).

CONCLUSIONPAMAM can effectively deliver survivin-ASODN into transplanted colorectal tumor cells to reduce the expression of survivin and inhibit the tumor growth.

Animals ; Cell Proliferation ; drug effects ; Colorectal Neoplasms ; pathology ; Dendrimers ; Humans ; Inhibitor of Apoptosis Proteins ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Microtubule-Associated Proteins ; genetics ; pharmacology ; Neoplasm Transplantation ; Oligonucleotides, Antisense ; pharmacology ; Polyamines ; pharmacology ; Repressor Proteins ; Tumor Cells, Cultured

OBJECTIVE: To determine the effect of RNA interference with transferred pshRNA/PHB on the biological characteristics of paclitaxel-resistant ovarian cancer cell lines. METHODS: Western blot and real time-PCR were used to assay the expression of PHB protein and mRNA in SKOV3/Taxol-25 and SKOV3 cell lines. The SKOV3/Taxol-25 cell lines were transiently transfected by 3 target-specific small hairpin RNA (shRNA) interference fragments with fluorescent protein named the pshRNA427/PHB1, pshRNA248/PHB2, and pshRNA136/PHB3. The empty plasmid transfection via vehicle Lipofectamine2000 served as a negative control. The expression levels of PHB protein and mRNA were detected by Western blot and real time-PCR after the transfection for 48 h. The silence effect of PHB1 and PHB3 groups was obvious. PHB1, PHB3, and the negative control groups were used for the following experiments. MTT and flow cytometry assay were used to test the cell proliferation, IC50 of paclitaxel, and cell apoptosis in the 3 groups. RESULTS: The expression levels of PHB protein and mRNA (2(-ΔΔCt)) were significantly higher in SKOV3/Taxol-25 cell line than those in SKOV3 cell line (P<0.05). The expression levels of PHB protein and mRNA were significantly lower in the PHB1 and PHB3 groups than those in the negative control group (P<0.05). The cell proliferations in the PHB1 and PHB3 groups were obviously slower than those in the negative control group after transfection for 48 h and 72 h (P<0.05). The IC50 of paclitaxel in the PHB1 and PHB3 groups significantly decreased after transfection for 72 h compared with the negative control group(P<0.05). The cell apoptotic rate in the PHB1 and PHB3 groups significantly increased after transfection for 48 h compared with the negative control group (P<0.05). CONCLUSION The shRNA/PHB can effectively suppress the expression of PHB gene in paclitaxel-resistant ovarian cancer cell lines. The cell proliferation in paclitaxel-resistant cell lines with removed PHB gene is significantly reduced. The apoptotic rate and the paclitaxel sensitivity of resistant cell lines with removed PHB gene are significantly increased. PHB gene is related to paclitaxel-resistance and interfering PHB gene expression may reduce paclitaxel resistance in ovarian cancer.
Antineoplastic Agents, Phytogenic ; pharmacology ; Drug Resistance, Neoplasm ; genetics ; Female ; Humans ; Ovarian Neoplasms ; genetics ; metabolism ; pathology ; Paclitaxel ; pharmacology ; RNA Interference ; RNA, Messenger ; genetics ; metabolism ; RNA, Small Interfering ; genetics ; Repressor Proteins ; genetics ; metabolism ; Transfection ; Tumor Cells, Cultured

OBJECTIVETo study the effect of alternative splicing form -MAD2beta of mitotic arrest deficient protein 2 (MAD2) on the formation of multidrug resistance in human gastric adenocarcinoma cell SGC7901.

METHODSRNA was extracted from a multidrug resistance cell line SGC7901/ADR. The full-length MAD2beta cDNA was obtained by RT-PCR and cloned into the pUCm-T vector, and then recombined into the eukaryotic expression vector pcDNA3.1 in forward direction. Subsequently, pcDNA3.1/MAD2beta vectors were then transfected into SGC7901 cells by lipofectamine. Sensitivity to drug was detected by MTT assay. Cell cycle alteration and intracellular fluorescence intensity were determined by FACS.

RESULTSA fragment of 0.53 Kb was obtained and confirmed by DNA sequencing which was a new alternative splicing form of MAD2 named as MAD2beta. pcDNA3.1/MAD2beta transfected SGC7901 cells (SGC7901/MAD2beta) were more resistant to ADR, VCR and MMC than the control cells (SGC7901/pcDNA3.1), and also ADR fluorescence intensity of SGC7901/MAD2beta cells was lower (P < 0.05) than that of SGC7901/pcDNA3.1 cells.

CONCLUSIONMAD2beta could increase the multidrug resistance of SGC7901 cell line.

Adenocarcinoma ; metabolism ; pathology ; Alternative Splicing ; Antibiotics, Antineoplastic ; pharmacology ; Antineoplastic Agents, Phytogenic ; pharmacology ; Calcium-Binding Proteins ; biosynthesis ; genetics ; Cell Cycle Proteins ; Cell Line, Tumor ; DNA-Binding Proteins ; biosynthesis ; genetics ; Doxorubicin ; pharmacology ; Drug Resistance, Multiple ; Drug Resistance, Neoplasm ; genetics ; Humans ; Mad2 Proteins ; Mitomycin ; pharmacology ; Repressor Proteins ; Smad2 Protein ; Stomach Neoplasms ; metabolism ; pathology ; Trans-Activators ; biosynthesis ; genetics ; Transfection ; Vincristine ; pharmacology

BACKGROUNDBisdemethoxycurcumin (BDMC) is an active component of curcumin and a chemotherapeutic agent, which has been suggested to inhibit tumor growth, invasion and metastasis in multiple cancers. But its contribution and mechanism of action in invasion and metastasis of non-small cell lung cancer (NSCLC) are not very clear. Therefore, we tried to study the effects of BDMC on regulation of epithelial-to-mesenchymal transition (EMT), which is closely linked to tumor cell invasion and metastasis.

METHODSIn this study, we first induced transforming growth factor-β1 (TGF-β1) mediated EMT in highly metastatic lung cancer 95D cells. Thereafter, we studied the effects of BDMC on invasion and migration of 95D cells. In addition, EMT markers expressions were also analyzed by western blot and immunofluorescence assays. The contribution of Wnt inhibitory factor-1 (WIF-1) in regulating BDMC effects on TGF-β1 induced EMT were further analyzed by its overexpression and small interfering RNA knockdown studies.

RESULTSIt was observed that BDMC inhibited the TGF-β1 induced EMT in 95D cells. Furthermore, it also inhibited the Wnt signaling pathway by upregulating WIF-1 protein expression. In addition, WIF-1 manipulation studies further revealed that WIF-1 is a central molecule mediating BDMC response towards TGF-β1 induced EMT by regulating cell invasion and migration.

CONCLUSIONSOur study concluded that BDMC effects on TGF-β1 induced EMT in NSCLC are mediated through WIF-1 and elucidated a novel mechanism of EMT regulation by BDMC.

Adaptor Proteins, Signal Transducing ; genetics ; metabolism ; Blotting, Western ; Cell Line, Tumor ; Cell Movement ; drug effects ; genetics ; Curcumin ; analogs & derivatives ; pharmacology ; Epithelial-Mesenchymal Transition ; drug effects ; genetics ; Humans ; Lung Neoplasms ; metabolism ; Repressor Proteins ; genetics ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction

Axin is a negative regulator of the Wnt/beta-catenin pathway and is involved in the regulation of axis formation and proliferation. Involvement of Axin in the regulation of other signaling pathways is poorly understood. In this study, we investigated the involvement of Akt in growth regulation by Axin in L929 fibroblasts stimulated by EGF. Akt activity was increased by EGF treatment and Ras activation, respectively. Both the EGF- and Ras-induced Akt activations were abolished by Axin induction, as revealed by both Western blot and immunocytochemical analyses. The proliferation and Akt activation induced by EGF were decreased by Axin induction, and the effects of EGF were abolished by treatment of an Akt-specific inhibitor. Therefore, Axin inhibits EGF-induced proliferation of L929 fibroblasts by blocking Akt activation.
Animals ; Cell Line ; Cell Nucleus/metabolism ; Cell Proliferation ; Epidermal Growth Factor/*pharmacology ; Fibroblasts/drug effects/physiology ; Mice ; Proto-Oncogene Proteins c-akt/antagonists & inhibitors/*metabolism ; Repressor Proteins/genetics/*physiology ; Signal Transduction ; ras Proteins/biosynthesis/genetics

AIMTo investigate the protective effects of ginkgolide B and hypoxic preconditioning against acute hypoxia injury in mice.

METHODSOrdinary pressure acute hypoxia model in mice was adopted to observe the ethology, the duration of the death and the degree of brain edema. Meanwhile the expression of RTP801 mRNA and erythropoietin (EPO) were measured by RT-PCR and Western blot, respectively.

RESULTSGinkgolide B and hypoxic preconditioning could both prolong the survival time of hypoxia under ordinary pressure,and significantly decreased the degree of brain edema. Besides ginkgolide B and hypoxic preconditioning could both up-regulate the expression of RTP801mRNA and EPO.

CONCLUSIONGinkgolide B has the similar effect to hypoxic preconditioning against acute hypoxia. Both of these protective effects may be associated with the up-regulation of the expression of RTP801 mRNA and EPO.

Animals ; Brain ; metabolism ; Brain Edema ; prevention & control ; Erythropoietin ; metabolism ; Female ; Ginkgolides ; pharmacology ; Hypoxia ; physiopathology ; Ischemic Preconditioning ; methods ; Lactones ; pharmacology ; Male ; Mice ; Mice, Inbred ICR ; RNA, Messenger ; genetics ; metabolism ; Reperfusion Injury ; prevention & control ; Repressor Proteins ; genetics ; metabolism ; Up-Regulation ; drug effects

BACKGROUND: Histone deacetylase 4 (HDAC4) regulates chondrocyte hypertrophy and bone formation. The aim of the present study was to explore the effects of HDAC4 on Interleukin 1 beta (IL-1β)-induced chondrocyte extracellular matrix degradation and whether it is regulated through the WNT family member 3A (WNT3A)/β-catenin signaling pathway. METHODS: Primary chondrocytes (CC) and human chondrosarcoma cells (SW1353 cells) were treated with IL-1β and the level of HDAC4 was assayed using Western blotting. Then, HDAC4 expression in the SW1353 cells was silenced using small interfering RNA to detect the effect of HDAC4 knockdown on the levels of matrix metalloproteinase 3 (MMP3) and MMP13 induced by IL-1β. After transfection with HDAC4 plasmids, the overexpression efficiency was examined using Real-time quantitative polymerase chain reaction (qRT-PCR) and the levels of MMP3 and MMP13 were assayed using Western blotting. After incubation with IL-1β, the translocation of β-catenin into the nucleus was observed using immunofluorescence staining in SW1353 cells to investigate the activation of the WNT3A/β-catenin signaling pathway. Finally, treatment with WNT3A and transfection with glycogen synthase kinase 3 beta (GSK3β) plasmids were assessed for their effects on HDAC4 levels using Western blotting. RESULTS: IL-1β downregulated HDAC4 levels in chondrocytes and SW1353 cells. Furthermore, HDAC4 knockdown increased the levels of MMP3 and MMP13, which contributed to the degradation of the extracellular matrix. Overexpression of HDAC4 inhibited IL-1β-induced increases in MMP3 and MMP13. IL-1β upregulated the levels of WNT3A, and WNT3A reduced HDAC4 levels in SW1353 cells. GSK-3β rescued IL-1β-induced downregulation of HDAC4 in SW1353 cells. CONCLUSION HDAC4 exerted an inhibitory effect on IL-1β-induced extracellular matrix degradation and was regulated partially by the WNT3A/β-catenin signaling pathway.
Cell Line, Tumor ; Cells, Cultured ; Chondrocytes/metabolism* ; Glycogen Synthase Kinase 3 beta/genetics* ; Histone Deacetylases/genetics* ; Humans ; Interleukin-1beta/pharmacology* ; Matrix Metalloproteinase 13/metabolism* ; Matrix Metalloproteinase 3 ; Repressor Proteins ; Wnt Signaling Pathway ; Wnt3A Protein/genetics* ; beta Catenin/metabolism*