The effect and mechanism of carmustine（BCNU） combined with all-trans retinoic acid（ATRA） on the apoptosis of human glioblastoma U251 cells were investigated by means of 3-（4,5-dimethylthiazol-2-yl）-2,5-diphe- ny...The effect and mechanism of carmustine（BCNU） combined with all-trans retinoic acid（ATRA） on the apoptosis of human glioblastoma U251 cells were investigated by means of 3-（4,5-dimethylthiazol-2-yl）-2,5-diphe- nyltetrazolium bromide（MTT） assay, flow cytometry, reverse transcription-polymerase chain reaction（RT-PCR） and Western blot analysis. The results show that BCNU or ATRA shows time- and dose-dependent inhibition effects on human glioblastoma U251 cells and the combination of BCNU with ATRA shows an synergistic inhibition effect on human glioblastoma U251 cells, and the combined BCNU and ATRA can significantly inhibit the proliferation of human glioblastoma U251 cells, and induce the apoptosis of them, making the cells arrest in the stage of G1 phase, the stage of S and G2 phases decline, the rate of the apoptosis of human glioblastoma U251 cells increase, the corresponding mRNA expression of cyclin E and cyclin-dependent kinase 2（CDK2） downregulated and the correspon- ding mRNA expression of p27kip 1 unregulated. In addition, the combined BCNU and ATRA reduced the protein expression of nuclear factor kappa B（NF-κB）. Taken together, these results suggest that the treatment of human glioblastoma U251 cells with a combination application of ATRA and BCNU can exert synergistic effect, the course of this kind of combination chemotherapy may likely be associated with multiple molecular mechanisms for apoptosis, furthermore, the cyclin E and p27kip 1 should be considered as novel targets for controlling the growth of glioblastoma cells.展开更多
Macrophage cells play an important role in the initiation and regulation of the immune response. All-trans retinoic acid (ATRA) and its natural and synthetic analogs (retinoids) affect a large number of biological pro...Macrophage cells play an important role in the initiation and regulation of the immune response. All-trans retinoic acid (ATRA) and its natural and synthetic analogs (retinoids) affect a large number of biological processes.Recently , retinoids have been shown promise in the therapy and prevention of various cancers. However, many interesting questions related to the activities of retinoids remain to be answered: (Ⅰ) Molecular mechanisms by which retinoids exert their effects; (Ⅱ) why the clinical uses of retinoids give undesirable side effects of varying severity with a higher freqllency of blood system symptoms; (Ⅲ)little is known for its impacts on macrophage cells etc. We set up this experiment, therefore, to examine the apoptosis of ATRA on macrophage Ana-1 cell line. Apoptosis of the cells was quantitated, after staining cells with propidium iodide (PI), by both accounting nuclear condensation and flow cytometry. When the cells were treated with ATRA at or higher than 1 μM for more than 24 h, significant amount of the apoptotic cells was observed. Induction of apoptosis of Ana-1 cells by ATRA was in time- and dose-dependent manners, exhibiting the similar pattern as the apoptosis induced by actinomycin D (ACTD). ATRA treatment of Ana-1 cells also caused the changes of the mRNA levels of apoptosis-associated gene bcl-2, as detected by Northern blot analysis. The temporal changes of bcl-2 expression by ATRA was also parallel to that by ACTD. In conclusion,ATRA can induce apoptosis in macrophage cells, which may be helpful in understanding of immunological functions retinoids.展开更多
Objective： To investigate the apoptosis of human pancreatic carcinoma PC3 cells induced by the combination of all-trans retinoic acid （ATRA） with interferon alpha （IFN-α）. Methods： PC3 cells were treated with ...Objective： To investigate the apoptosis of human pancreatic carcinoma PC3 cells induced by the combination of all-trans retinoic acid （ATRA） with interferon alpha （IFN-α）. Methods： PC3 cells were treated with ATRA and IFN-α. The inhibitory rate of PC3 cell proliferation was detected using MTT method. Cellular apoptosis was determined with flow cytometry. The percentage of PC3 cell apoptosis was assayed using TUNEL methods. Results： ATRA and IFN-α could inhibit cellular proliferation and induces cellular apoptosis of PC3 cells. The inhibitory effect was stronger when the ATRA and IFN-α were combined as a therapy. Conclusion： ATRA inhibits the proliferation of PC3 cells and induce the apoptosis of PC3 cells. The combination of IFN-α with ATRA may enhance these effects on PC3 cells.展开更多
Objective:Local recurrence of hepatocellular carcinoma(HCC)after radiofrequency ablation(RFA)treatment remains a serious problem.Tumor-initiating cells(TICs)are thought to be responsible for tumor relapse.Here,we inve...Objective:Local recurrence of hepatocellular carcinoma(HCC)after radiofrequency ablation(RFA)treatment remains a serious problem.Tumor-initiating cells(TICs)are thought to be responsible for tumor relapse.Here,we investigated the effect of the TIC differentiation inducer,all-trans retinoic acid(ATRA),on RFA and explored the potential molecular mechanisms.Methods:The proportions of CD133+and epithelial cell adhesion molecule(Ep CAM);TICs in recurrent HCC after RFA and primary HCC were first determined in clinic.Then,the effect of heat intervention or insufficient RFA(IRFA)on the malignant potential of HCC cells,including cell migration,sphere formation ability,tumor growth,the proportion of CD133+and Ep CAM+TICs and expression of stem cell-related genes,was evaluated in vitro and in vivo.Finally,the effect of ATRA on the tumor growth and the proportion of TICs was evaluated.Results:In clinical data,a higher proportion of CD133+and Ep CAM+TICs was found in recurrent tumors than in primary tumors.In vitro heat intervention promoted the cell migration and sphere formation ability.Additionally,it increased the proportion of CD133+and Ep CAM+TICs and the expression of stem cell-related genes.In addition,after IRFA the residual tumors in xenografts grew faster and had more TICs than untreated tumors.ATRA remarkably inhibited residual tumor growth after IRFA by elimination of TICs though the PI3 K/AKT pathway.Combination treatment with ATRA resulted in longer survival outcomes in mouse xenografts than RFA alone.Conclusions:ATRA,as a TIC differentiation inducer,could help to improve the effect of RFA treatment,which was partially attributed to its effect against TICs.The data indicated its potential as an alternative drug in the development of better therapeutic strategies for use in combination with RFA.展开更多
Objective： To explore the combination effects of all-trans retinoic acid （ATRA） with interferon-gamma （IFN-γ） on human hepatocarcinoma cell line SMMC-7721 and the mechanism of action. Methods： SMMC-7721 cells w...Objective： To explore the combination effects of all-trans retinoic acid （ATRA） with interferon-gamma （IFN-γ） on human hepatocarcinoma cell line SMMC-7721 and the mechanism of action. Methods： SMMC-7721 cells were divided into treated group and control group. The cells were treated with ATRA or ATRA＋ IFN-γ in the former and added with PBS in the latter. The inhibition rate of SMMC-7721 cell proliferation was detected by MTT, the cell change in morphology was observed by electron microscope. The apoptosis was detected by flow cytometry and the expression changes of nuclear factor-kappaB （NF-κB） was analyzed by Western blotting when the SMMC-7721 cells were treated with ATRA and IFN-γ. Results： The SMMC-7721 cell proliferation was suppressed and apoptosis was induced after the cells were treated with ATRA treatment, and these effects were enhanced when ATRA was combined with IFN-γ. The expression of NF-κB was reduced after SMMC-7721 cell was treated with ATRA, and reduced significantly when the cells were treated with the combination of ATRA and IFN-γ. Conclusion： IFN-γ can enhance the inhibiting effects of ATRA on cell proliferation and inducing apoptosis on SMMC-7721 cell and these effects might be mediated by inhibiting the expression of NF-κB.展开更多
Objective To observe the effects of retinoic acid (RA) on the proliferation and differentiation of a human ovarian carcino-ma cell line: 3AO cells. Methods 3AO cell proliferation was evaluated by viable cell count, pe...Objective To observe the effects of retinoic acid (RA) on the proliferation and differentiation of a human ovarian carcino-ma cell line: 3AO cells. Methods 3AO cell proliferation was evaluated by viable cell count, percentage of cells in each cycle phase were analyzed by flow cytometric analysis, alkaline phosphatase (AKP) activity was determined as described , and CA125 expression was measured by ELISA. Results RA could inhibit the proliferation of 3AO cells accompanied with morphological changes in a dose-dependent manner. Cell cycle analysis indicated that RA inhibition of 3AO cells growth occurred through induction of G1 arrest with a concomitant reduction in the proportion of cells in S phase, AKP activity increased significantly after treatment with RA(0.1 μmol/L) for 1-5 days. Dose-response studies revealed that the AKP activity increased to a different extent as a function of RA concentrations. Furthermore, RA could suppress the expression of CA125 tumor marker in 3AO cells.Conclusion RA could markedly inhibit the proliferation and induce the differentiation of 3AO cells. for 1-5 days. Dose展开更多
To characterize the genes associated with differentiation/apoptosis induced by all-trans retinoic acid (ATRA) in human lung cancer cells, mRNA differential display was employed. Six cDNA fragments have been isolated, ...To characterize the genes associated with differentiation/apoptosis induced by all-trans retinoic acid (ATRA) in human lung cancer cells, mRNA differential display was employed. Six cDNA fragments have been isolated, and one of them corresponds to a sequence-known gene DPH2L with unknown function, which was first isolated from the critical region of deletion on chromosome 17p13.3 in human ovarian carcinoma, and regarded as a candidate tumor suppressor gene. Results show that DPH2L is a wide expressed gene, and has another major transcript besides the previously reported 2.3 kb transcript. It is proved that the DPH2L gene is dawn-regulated during differentiation or apoptosis in several kinds of cancer cells induced by all-trans retinoic acid and N-(4-hydroxyphenyl) retinamide (4HPR). This may suggest that DPH2L does not play a role as a tumor suppressor gene, on the contrary, its down-regulation may be functionally involved in the transition from cell growth to differentiation or apoptosis.展开更多
Objective The treatment of solid tumors by means of differentiation induction has not yet beengained such broken - through success as all-trans retinoic acid (ATRA) in acute promyelocytic leukemia (APL).To explore mor...Objective The treatment of solid tumors by means of differentiation induction has not yet beengained such broken - through success as all-trans retinoic acid (ATRA) in acute promyelocytic leukemia (APL).To explore more effective inducers for solid tumor therapy, dimethyl sulfoxide (DMSO) is considered as acandidate. Methods In the present study, DMSO was used as inducer to human esophageal cancer cell lines invitro, in compared with classical inducer ATRA, in terms of morphology, cell cycle, growth inhibition, cytokeratin4 expression, gap junction-mediated dye transfer and tumorigenecity in nude mice. Results DMSO as well asATRA induced differentiation of human esophageal carcinoma cells. However, DMSO was confirmed to be moreeffective for induced differentiation of esophageal carcinoma cells than ATRA. Conclusion The results suggestedthat DMSO might have a good prospect in the treatment of solid tumors.展开更多
基金Supported by the National Natural Science Foundation of China(No.30672159)the Fund of Jilin Provincial Science & Technology Department, China(No.200905173)
文摘The effect and mechanism of carmustine（BCNU） combined with all-trans retinoic acid（ATRA） on the apoptosis of human glioblastoma U251 cells were investigated by means of 3-（4,5-dimethylthiazol-2-yl）-2,5-diphe- nyltetrazolium bromide（MTT） assay, flow cytometry, reverse transcription-polymerase chain reaction（RT-PCR） and Western blot analysis. The results show that BCNU or ATRA shows time- and dose-dependent inhibition effects on human glioblastoma U251 cells and the combination of BCNU with ATRA shows an synergistic inhibition effect on human glioblastoma U251 cells, and the combined BCNU and ATRA can significantly inhibit the proliferation of human glioblastoma U251 cells, and induce the apoptosis of them, making the cells arrest in the stage of G1 phase, the stage of S and G2 phases decline, the rate of the apoptosis of human glioblastoma U251 cells increase, the corresponding mRNA expression of cyclin E and cyclin-dependent kinase 2（CDK2） downregulated and the correspon- ding mRNA expression of p27kip 1 unregulated. In addition, the combined BCNU and ATRA reduced the protein expression of nuclear factor kappa B（NF-κB）. Taken together, these results suggest that the treatment of human glioblastoma U251 cells with a combination application of ATRA and BCNU can exert synergistic effect, the course of this kind of combination chemotherapy may likely be associated with multiple molecular mechanisms for apoptosis, furthermore, the cyclin E and p27kip 1 should be considered as novel targets for controlling the growth of glioblastoma cells.
文摘Macrophage cells play an important role in the initiation and regulation of the immune response. All-trans retinoic acid (ATRA) and its natural and synthetic analogs (retinoids) affect a large number of biological processes.Recently , retinoids have been shown promise in the therapy and prevention of various cancers. However, many interesting questions related to the activities of retinoids remain to be answered: (Ⅰ) Molecular mechanisms by which retinoids exert their effects; (Ⅱ) why the clinical uses of retinoids give undesirable side effects of varying severity with a higher freqllency of blood system symptoms; (Ⅲ)little is known for its impacts on macrophage cells etc. We set up this experiment, therefore, to examine the apoptosis of ATRA on macrophage Ana-1 cell line. Apoptosis of the cells was quantitated, after staining cells with propidium iodide (PI), by both accounting nuclear condensation and flow cytometry. When the cells were treated with ATRA at or higher than 1 μM for more than 24 h, significant amount of the apoptotic cells was observed. Induction of apoptosis of Ana-1 cells by ATRA was in time- and dose-dependent manners, exhibiting the similar pattern as the apoptosis induced by actinomycin D (ACTD). ATRA treatment of Ana-1 cells also caused the changes of the mRNA levels of apoptosis-associated gene bcl-2, as detected by Northern blot analysis. The temporal changes of bcl-2 expression by ATRA was also parallel to that by ACTD. In conclusion,ATRA can induce apoptosis in macrophage cells, which may be helpful in understanding of immunological functions retinoids.
文摘Objective： To investigate the apoptosis of human pancreatic carcinoma PC3 cells induced by the combination of all-trans retinoic acid （ATRA） with interferon alpha （IFN-α）. Methods： PC3 cells were treated with ATRA and IFN-α. The inhibitory rate of PC3 cell proliferation was detected using MTT method. Cellular apoptosis was determined with flow cytometry. The percentage of PC3 cell apoptosis was assayed using TUNEL methods. Results： ATRA and IFN-α could inhibit cellular proliferation and induces cellular apoptosis of PC3 cells. The inhibitory effect was stronger when the ATRA and IFN-α were combined as a therapy. Conclusion： ATRA inhibits the proliferation of PC3 cells and induce the apoptosis of PC3 cells. The combination of IFN-α with ATRA may enhance these effects on PC3 cells.
基金supported by National Natural Science Foundation of China(No.81773286,81971718,and 81772632)Beijing Baiqianwan Talents Project(No.2020A47)Science Foundation of Peiking University Cancer Hospital(No.2020-9)。
文摘Objective:Local recurrence of hepatocellular carcinoma(HCC)after radiofrequency ablation(RFA)treatment remains a serious problem.Tumor-initiating cells(TICs)are thought to be responsible for tumor relapse.Here,we investigated the effect of the TIC differentiation inducer,all-trans retinoic acid(ATRA),on RFA and explored the potential molecular mechanisms.Methods:The proportions of CD133+and epithelial cell adhesion molecule(Ep CAM);TICs in recurrent HCC after RFA and primary HCC were first determined in clinic.Then,the effect of heat intervention or insufficient RFA(IRFA)on the malignant potential of HCC cells,including cell migration,sphere formation ability,tumor growth,the proportion of CD133+and Ep CAM+TICs and expression of stem cell-related genes,was evaluated in vitro and in vivo.Finally,the effect of ATRA on the tumor growth and the proportion of TICs was evaluated.Results:In clinical data,a higher proportion of CD133+and Ep CAM+TICs was found in recurrent tumors than in primary tumors.In vitro heat intervention promoted the cell migration and sphere formation ability.Additionally,it increased the proportion of CD133+and Ep CAM+TICs and the expression of stem cell-related genes.In addition,after IRFA the residual tumors in xenografts grew faster and had more TICs than untreated tumors.ATRA remarkably inhibited residual tumor growth after IRFA by elimination of TICs though the PI3 K/AKT pathway.Combination treatment with ATRA resulted in longer survival outcomes in mouse xenografts than RFA alone.Conclusions:ATRA,as a TIC differentiation inducer,could help to improve the effect of RFA treatment,which was partially attributed to its effect against TICs.The data indicated its potential as an alternative drug in the development of better therapeutic strategies for use in combination with RFA.
文摘Objective： To explore the combination effects of all-trans retinoic acid （ATRA） with interferon-gamma （IFN-γ） on human hepatocarcinoma cell line SMMC-7721 and the mechanism of action. Methods： SMMC-7721 cells were divided into treated group and control group. The cells were treated with ATRA or ATRA＋ IFN-γ in the former and added with PBS in the latter. The inhibition rate of SMMC-7721 cell proliferation was detected by MTT, the cell change in morphology was observed by electron microscope. The apoptosis was detected by flow cytometry and the expression changes of nuclear factor-kappaB （NF-κB） was analyzed by Western blotting when the SMMC-7721 cells were treated with ATRA and IFN-γ. Results： The SMMC-7721 cell proliferation was suppressed and apoptosis was induced after the cells were treated with ATRA treatment, and these effects were enhanced when ATRA was combined with IFN-γ. The expression of NF-κB was reduced after SMMC-7721 cell was treated with ATRA, and reduced significantly when the cells were treated with the combination of ATRA and IFN-γ. Conclusion： IFN-γ can enhance the inhibiting effects of ATRA on cell proliferation and inducing apoptosis on SMMC-7721 cell and these effects might be mediated by inhibiting the expression of NF-κB.
文摘Objective To observe the effects of retinoic acid (RA) on the proliferation and differentiation of a human ovarian carcino-ma cell line: 3AO cells. Methods 3AO cell proliferation was evaluated by viable cell count, percentage of cells in each cycle phase were analyzed by flow cytometric analysis, alkaline phosphatase (AKP) activity was determined as described , and CA125 expression was measured by ELISA. Results RA could inhibit the proliferation of 3AO cells accompanied with morphological changes in a dose-dependent manner. Cell cycle analysis indicated that RA inhibition of 3AO cells growth occurred through induction of G1 arrest with a concomitant reduction in the proportion of cells in S phase, AKP activity increased significantly after treatment with RA(0.1 μmol/L) for 1-5 days. Dose-response studies revealed that the AKP activity increased to a different extent as a function of RA concentrations. Furthermore, RA could suppress the expression of CA125 tumor marker in 3AO cells.Conclusion RA could markedly inhibit the proliferation and induce the differentiation of 3AO cells. for 1-5 days. Dose
文摘To characterize the genes associated with differentiation/apoptosis induced by all-trans retinoic acid (ATRA) in human lung cancer cells, mRNA differential display was employed. Six cDNA fragments have been isolated, and one of them corresponds to a sequence-known gene DPH2L with unknown function, which was first isolated from the critical region of deletion on chromosome 17p13.3 in human ovarian carcinoma, and regarded as a candidate tumor suppressor gene. Results show that DPH2L is a wide expressed gene, and has another major transcript besides the previously reported 2.3 kb transcript. It is proved that the DPH2L gene is dawn-regulated during differentiation or apoptosis in several kinds of cancer cells induced by all-trans retinoic acid and N-(4-hydroxyphenyl) retinamide (4HPR). This may suggest that DPH2L does not play a role as a tumor suppressor gene, on the contrary, its down-regulation may be functionally involved in the transition from cell growth to differentiation or apoptosis.
文摘Objective The treatment of solid tumors by means of differentiation induction has not yet beengained such broken - through success as all-trans retinoic acid (ATRA) in acute promyelocytic leukemia (APL).To explore more effective inducers for solid tumor therapy, dimethyl sulfoxide (DMSO) is considered as acandidate. Methods In the present study, DMSO was used as inducer to human esophageal cancer cell lines invitro, in compared with classical inducer ATRA, in terms of morphology, cell cycle, growth inhibition, cytokeratin4 expression, gap junction-mediated dye transfer and tumorigenecity in nude mice. Results DMSO as well asATRA induced differentiation of human esophageal carcinoma cells. However, DMSO was confirmed to be moreeffective for induced differentiation of esophageal carcinoma cells than ATRA. Conclusion The results suggestedthat DMSO might have a good prospect in the treatment of solid tumors.
