AIM: To investigate the killing effect and radiosensitization of double suicide gene mediated by adenovirus on colorectal carcinoma cells.METHODS: Colorectal carcinoma cell line SW480 was transfected with adenovirus e...AIM: To investigate the killing effect and radiosensitization of double suicide gene mediated by adenovirus on colorectal carcinoma cells.METHODS: Colorectal carcinoma cell line SW480 was transfected with adenovirus expression vector containing cytosine deaminase (CD) and thymidine kinase (Tk) fusion gene. The expression of CD-TK fusion gene was detected by reverse transcriptase-polymerase chain reaction. The toxic effect of ganciclovir (GCV) and 5-fiuorocytosine (5FC) on infected cells was determined by MTT assay. The radiosensitization of double suicide gene was evaluated by clonogenic assay.RESULTS: After prodrugs were used, the survival rate of colorectal carcinoma cells was markedly decreased. When GCV and 5-FC were used in combination, the cytotoxicity and bystandereffect were markedly superior to a single prodrug (x2 = 30.371, P<0.01). Both GCV and 5-FC could sensitize colorectal carcinoma cells to the toxic effect of radiation, and greater radiosensitization was achieved when both prodrug were used in combination. CONCLUSION: CD-TK double suicide gene can kill and radiosensitize colorectal carcinoma cells.展开更多
大蒜素是大蒜中提取的单体,近年来的研究表明大蒜素有明显的抗癌作用,如大蒜素显著抑制 K562和 HR-8348细胞株的增殖,阻留 S 期的细胞于 G_2/M 期,并对抗癌药有增敏作用。我们的实验显示大蒜素可显著诱导人急性白血病 T 淋巴细胞株(6T-C...大蒜素是大蒜中提取的单体,近年来的研究表明大蒜素有明显的抗癌作用,如大蒜素显著抑制 K562和 HR-8348细胞株的增殖,阻留 S 期的细胞于 G_2/M 期,并对抗癌药有增敏作用。我们的实验显示大蒜素可显著诱导人急性白血病 T 淋巴细胞株(6T-CEM)细胞凋亡,并有明显的时间和剂量效应。本研究通过观察放线菌素 D 和放线菌酮对大蒜素诱导6T-CEM细胞凋亡的影响及大蒜素对6T-CEM 细胞凋亡基因表达的影响,进一步探讨大蒜素诱导6T-CEM 细胞凋亡机理。材料和方法1 材料 6T-CEM(中国科学院上海分院细胞所)用含10%的小牛血清的 RPMI-1640(GBICO)安全培养液培养。展开更多
Objective: To improve DC-based tumor vaccination, we studied whether dendritic cells (DCs) which cocultured with H22 liver cancer cells-derived heat shock protein (HSP) glycoprotein 96 (gp96) affect the T cell-activat...Objective: To improve DC-based tumor vaccination, we studied whether dendritic cells (DCs) which cocultured with H22 liver cancer cells-derived heat shock protein (HSP) glycoprotein 96 (gp96) affect the T cell-activating potential in vitro and the induction of tumor immunity in vivo. Methods: Maturation of murine bone marrow-derived DC was induced by GM-CSF plus IL-4. which mimiced the immunostimulatory effect of DC. Cocultured DC and gp96-peptide complexes were used to vaccine H22 liver cancer cells of mice. Using murine models we compared the immunogenecity of DC modified by gp96-peptides complexes derived from murine liver cancer cells alone or inactive tumor cells. To verify the specificity of the vaccine, in vitro assays were executed. Serum cytokine levels were quantified to explore the supposed pathway of DC modified by gp96 peptide complexes and its effect on antitumor immune response. Results: DC modified by gp96-peptide complexes can activate spleen lymphocyte and the latter can specifically kill H22 cells but not Ehrilich ascites carcinoma cells. Modified DC can induce potent tumor-antigenspecific immune response, augment the proliferation of Th1 cells, and inhibit tumor growth. Conclusion: In this study, we have developed a novel DC-mediated tumor vaccine by combing the gp96 antigenic peptides complexes and inducing immune response against specific tumor cells. gp96 can be identified as a potent DC activator.展开更多
AIM: To study the in vitro and in vivo antitumor effect of lidamycin (LDM) on hepatoma and the active moiety of its molecule.METHODS: MTT assay was used to determine the growth inhibition of human hepatoma BEL-7402 ce...AIM: To study the in vitro and in vivo antitumor effect of lidamycin (LDM) on hepatoma and the active moiety of its molecule.METHODS: MTT assay was used to determine the growth inhibition of human hepatoma BEL-7402 cells, SMMC-7721cells and mouse hepatoma H22 cells. The in vivo therapeutic effects of lidamycin and mitomycin C were determined by transplantable hepatoma 22 (H22) in mice and human hepatoma BEL-7402 xenografts in athymic mice.RESULTS: In terms of IC50values, the cytotoxicity of LDM was 10 000-fold more potent than that of mitomycin C (MMC)and adriamycin (ADM) in human hepatoma BEL-7402 cells and SMMC-7721 cells. LDM molecule consists of two moieties,an aproprotein (LDP) and an enediyne chromophore (LDC). In terms of IC50 values, the potency of LDC was similar to LDM. However, LDP was 105-fold less potent than LDM and LDC to hepatoma cells. For mouse hepatoma H22 cells, the IC50value of LDM was 0.025 nmol/L. Given by single intravenous injection at doses of 0.1, 0.05 and 0.025 mg/kg, LDM markedly suppressed the growth of hepatoma 22 in mice by 84.7%, 71.6% and 61.8%,respectively. The therapeutic indexes (TI) of LDM and MMC were 15 and 2.5, respectively. By 2 iv. Injections in two experiments, the growth inhibition rates by LDM at doses of 0.1, 0.05, 0.025, 0.00625 and 0.0125 mg/kg were 88.8-89.5%, 81.1-82.5%, 71.2-74.9%, 52.3-59.575%,and 33.3-48.3%, respectively. In comparison, MMC at doses of 5, 2.5, and 1.25 mg/kg inhibited tumor growth by 69.7-73.6%, 54.0-56.5%, and 31.5-52.2%,respectively. Moreover, in human hepatoma BEL-7402 xenografts, the growth inhibition rates by LDM at doses of 0.05 mg/kg ×2 and 0.025 mg/kg ×2 were 68.7%and 27.2%, respectively. However, MMC at the dose of 1.25 mg/kg ×2 showed an inhibition rate of 34.5%. The inhibition rate of tumor growth by LDM was higher than that by MMC at the tolerated dose.CONCLUSION: Both LDM and its chromophore LDC display extremely potent cytotoxicity to hepatoma cells. LDM shows a remarkable therapeutic efficacy against murine and human hepatomas in vivo.展开更多
AIM: To investigate the inhibitory effect of gefitinib combined with cytotoxic agent cisplatin (CDDP) on hepatocellular carcinoma (HCC).METHODS: Female Kunming mice and H22 hepatocarcinorna cells were used. Gefitinib ...AIM: To investigate the inhibitory effect of gefitinib combined with cytotoxic agent cisplatin (CDDP) on hepatocellular carcinoma (HCC).METHODS: Female Kunming mice and H22 hepatocarcinorna cells were used. Gefitinib at daily dose of 100 mg/kg body weight (BW) or lecithin liquid was given by gastrogavage once a day for 5 or 10 successive days.CDDP or normal saline (NS) was administered intraperitoneally (i.p.) once a day for 5 successive days.Mice were randomly divided into control group (lecithin,or NS, i.p.), CDDP group (daily dose, 1.2 mg/kg BW; d1-5,or d6-10), Gefitinib (d1-5, or d6-10, or d1-10), and Gefitinib combined with CDDP groups. The inhibitory rate (IR) of tumor, net BW, spleen index (SI), thymus index(TI) and the amount of peripheral blood cells of mice were detected on the 12th experiment day.RESULTS: The growth of HCC in mice was inhibited by Gefitinib alone (IR: 41% in d1-10 group and 30% in d1-5group, respectively) or CDDP alone (IR: 32-54% in d1-5group or d6-10 group). The highest inhibitory effect (IR:56%) on HCC growth was observed in Gefitinib (d1-10)combined with CDDP (d1-5) group. Higher inhibition was also observed in CDDP (d1-5) followed by Gefitinib (d6-10)group than that in Gefitinib (d1-5) followed by CDDP (d6-10) group (IR: 61% vs36%, P<0.01) in the independent study. Net BW, SI, TI and the amount of blood cells of mice in Gefitinib alone group were not significantly different from those in control groups.CONCLUSION: Gefitinib can significantly inhibit the growth of murine H22 hepatocellular carcinoma. If Gefitinib is used after CDDP treatment in animal experiments, the inhibitory effect could be enhanced.展开更多
文摘AIM: To investigate the killing effect and radiosensitization of double suicide gene mediated by adenovirus on colorectal carcinoma cells.METHODS: Colorectal carcinoma cell line SW480 was transfected with adenovirus expression vector containing cytosine deaminase (CD) and thymidine kinase (Tk) fusion gene. The expression of CD-TK fusion gene was detected by reverse transcriptase-polymerase chain reaction. The toxic effect of ganciclovir (GCV) and 5-fiuorocytosine (5FC) on infected cells was determined by MTT assay. The radiosensitization of double suicide gene was evaluated by clonogenic assay.RESULTS: After prodrugs were used, the survival rate of colorectal carcinoma cells was markedly decreased. When GCV and 5-FC were used in combination, the cytotoxicity and bystandereffect were markedly superior to a single prodrug (x2 = 30.371, P<0.01). Both GCV and 5-FC could sensitize colorectal carcinoma cells to the toxic effect of radiation, and greater radiosensitization was achieved when both prodrug were used in combination. CONCLUSION: CD-TK double suicide gene can kill and radiosensitize colorectal carcinoma cells.
基金Supported by the National Natural Science Foundation of China (No. 30200369)
文摘Objective: To improve DC-based tumor vaccination, we studied whether dendritic cells (DCs) which cocultured with H22 liver cancer cells-derived heat shock protein (HSP) glycoprotein 96 (gp96) affect the T cell-activating potential in vitro and the induction of tumor immunity in vivo. Methods: Maturation of murine bone marrow-derived DC was induced by GM-CSF plus IL-4. which mimiced the immunostimulatory effect of DC. Cocultured DC and gp96-peptide complexes were used to vaccine H22 liver cancer cells of mice. Using murine models we compared the immunogenecity of DC modified by gp96-peptides complexes derived from murine liver cancer cells alone or inactive tumor cells. To verify the specificity of the vaccine, in vitro assays were executed. Serum cytokine levels were quantified to explore the supposed pathway of DC modified by gp96 peptide complexes and its effect on antitumor immune response. Results: DC modified by gp96-peptide complexes can activate spleen lymphocyte and the latter can specifically kill H22 cells but not Ehrilich ascites carcinoma cells. Modified DC can induce potent tumor-antigenspecific immune response, augment the proliferation of Th1 cells, and inhibit tumor growth. Conclusion: In this study, we have developed a novel DC-mediated tumor vaccine by combing the gp96 antigenic peptides complexes and inducing immune response against specific tumor cells. gp96 can be identified as a potent DC activator.
基金Supported by the National High Technology Research and Development Program of China (863 program), No. 2002AA2Z3107
文摘AIM: To study the in vitro and in vivo antitumor effect of lidamycin (LDM) on hepatoma and the active moiety of its molecule.METHODS: MTT assay was used to determine the growth inhibition of human hepatoma BEL-7402 cells, SMMC-7721cells and mouse hepatoma H22 cells. The in vivo therapeutic effects of lidamycin and mitomycin C were determined by transplantable hepatoma 22 (H22) in mice and human hepatoma BEL-7402 xenografts in athymic mice.RESULTS: In terms of IC50values, the cytotoxicity of LDM was 10 000-fold more potent than that of mitomycin C (MMC)and adriamycin (ADM) in human hepatoma BEL-7402 cells and SMMC-7721 cells. LDM molecule consists of two moieties,an aproprotein (LDP) and an enediyne chromophore (LDC). In terms of IC50 values, the potency of LDC was similar to LDM. However, LDP was 105-fold less potent than LDM and LDC to hepatoma cells. For mouse hepatoma H22 cells, the IC50value of LDM was 0.025 nmol/L. Given by single intravenous injection at doses of 0.1, 0.05 and 0.025 mg/kg, LDM markedly suppressed the growth of hepatoma 22 in mice by 84.7%, 71.6% and 61.8%,respectively. The therapeutic indexes (TI) of LDM and MMC were 15 and 2.5, respectively. By 2 iv. Injections in two experiments, the growth inhibition rates by LDM at doses of 0.1, 0.05, 0.025, 0.00625 and 0.0125 mg/kg were 88.8-89.5%, 81.1-82.5%, 71.2-74.9%, 52.3-59.575%,and 33.3-48.3%, respectively. In comparison, MMC at doses of 5, 2.5, and 1.25 mg/kg inhibited tumor growth by 69.7-73.6%, 54.0-56.5%, and 31.5-52.2%,respectively. Moreover, in human hepatoma BEL-7402 xenografts, the growth inhibition rates by LDM at doses of 0.05 mg/kg ×2 and 0.025 mg/kg ×2 were 68.7%and 27.2%, respectively. However, MMC at the dose of 1.25 mg/kg ×2 showed an inhibition rate of 34.5%. The inhibition rate of tumor growth by LDM was higher than that by MMC at the tolerated dose.CONCLUSION: Both LDM and its chromophore LDC display extremely potent cytotoxicity to hepatoma cells. LDM shows a remarkable therapeutic efficacy against murine and human hepatomas in vivo.
文摘AIM: To investigate the inhibitory effect of gefitinib combined with cytotoxic agent cisplatin (CDDP) on hepatocellular carcinoma (HCC).METHODS: Female Kunming mice and H22 hepatocarcinorna cells were used. Gefitinib at daily dose of 100 mg/kg body weight (BW) or lecithin liquid was given by gastrogavage once a day for 5 or 10 successive days.CDDP or normal saline (NS) was administered intraperitoneally (i.p.) once a day for 5 successive days.Mice were randomly divided into control group (lecithin,or NS, i.p.), CDDP group (daily dose, 1.2 mg/kg BW; d1-5,or d6-10), Gefitinib (d1-5, or d6-10, or d1-10), and Gefitinib combined with CDDP groups. The inhibitory rate (IR) of tumor, net BW, spleen index (SI), thymus index(TI) and the amount of peripheral blood cells of mice were detected on the 12th experiment day.RESULTS: The growth of HCC in mice was inhibited by Gefitinib alone (IR: 41% in d1-10 group and 30% in d1-5group, respectively) or CDDP alone (IR: 32-54% in d1-5group or d6-10 group). The highest inhibitory effect (IR:56%) on HCC growth was observed in Gefitinib (d1-10)combined with CDDP (d1-5) group. Higher inhibition was also observed in CDDP (d1-5) followed by Gefitinib (d6-10)group than that in Gefitinib (d1-5) followed by CDDP (d6-10) group (IR: 61% vs36%, P<0.01) in the independent study. Net BW, SI, TI and the amount of blood cells of mice in Gefitinib alone group were not significantly different from those in control groups.CONCLUSION: Gefitinib can significantly inhibit the growth of murine H22 hepatocellular carcinoma. If Gefitinib is used after CDDP treatment in animal experiments, the inhibitory effect could be enhanced.