Lentivirus mediated RNAi silence esophageal MDC1 Eca109 cell gene expression of the influence of nude mouse transplantation tumor radiosensitivity / 中华放射肿瘤学杂志

Objective To investigate the effects of inhibition of MDC1 protein expression on xenografted tumors in nude mice,and to observe the histopathological and cellular changes in nude mice.Methods Three pairs of effective and control short hairpin RNA targeting MDC1 mRNA were designed and cloned into the pSIH1-H1-copGFP vector.Real-time PCR and Western blot were used to determine the mRNA and protein expression of MDC1.After selection by copGFP reporter gene,cells were divided into negative transfection group (ECA109-N) and MDC1 transfection group (ECA109-M).The transfected cells were injected into nude mice.The mice were divided into ECA109 group,ECA109-N group,and ECA109-M group.Each group was divided into irradiation subgroup and non-irradiation subgroup.The changes in tumor size after irradiation were evaluated in each group.Western blot was used to measure the expression of CHK1,CHK2,and CHK2T68 in xenografted tumors.Flow cytometry was used to analyze the cell cycle distribution and apoptosis of tumor cells in nude mice.The variance analysis was used to compare the mean of multiple groups,and the SNK-q test was used in the two two groups.Results The pMDC1-shRNA plasmid was successfully constructed and used to transfect ECA109 cells.ECA109-M cells were obtained by stable transfection with the recombinant plasmid.All inoculated nude mice survived with visible xenografted tumors at the underside of the paw in about one week.There was no swelling and wound in inoculation sites.There was no significant difference in tumor size between different groups (P＞0.05).The tumor growth in the ECA109 group and the ECA109-N group significantly slowed down after irradiation with a dose of 15 Gy (P＜0.05).Compared with the other two groups,the ECA109-M group had a significant smaller tumor size,significantly slower relative tumor growth,and significantly higher growth inhibition (all P＜0.05).The q value of the ECA109-M group was 1.36.In the ECA109-M group,there were no significant changes in the protein expression of CHK1 and CHK2 after irradiation (P＞ 0.05);however,the phosphorylation of CHK2T68 protein was significantly reduced after irradiation (P＜0.05).There were no significant differences in cell cycle distribution or the proportion of apoptotic cells in tumor tissue between the three groups (P＞0.05).Conclusions Inhibition of MDC1 protein expression by RNA interference can effectively inhibit the growth of xenografted tumors after irradiation in the nude mice by increasing their radiosensitivity.

Dose response of CpG ODN1826 and its combination effect with X-ray irradiation on Lewis lung cancer in mice / 中华放射医学与防护杂志

Objective To explore the combination effect of unmethylated cytosine-phosphate-guanine oligodeoxynucleotide (CpG ODN) 1826 and X-rays on Lewis lung cancer in mouse and the dose response of CpG ODN.Methods The tumor-bearing mouse model was established by injecting Lewis lung cancer cells into the right infra-axillary dermis of mouse.Sixty-four C57BL /6 J mice were evenly randomized into eight groups with 8 mice each:control group,IR group,CpG OND1826 0.15 mg group,CpG OND1826 0.3 mg group,CpG OND1826 0.45 mg group,CpG OND1826 0.15 mg + IR group,CpG OND1826 0.30 mg+ IR group,and CpG OND1826 0.45 mg + IR group.On the 1st,2nd,and 9th days,CpG ODN was injected into mouse.After 3 hours of injection,the mice were start to irradiate with X-rays once a day on the 2nd-6th days,and the total dose was 12.50 Gy.Tumor growth and TGD were measured,and the apoptosis of tumor cells were examined with TUNEL.Results The Lewis lung cancer-bearing model was successfully established in all mice.Under the treatments of CpG OND1826 and irradiation,the tumor volumes were smaller than that of control group,and the tumor volumes of CpG OND1826 0.45 mg+IR group was the smallest.TUNEL results revealed that the apoptosis rate were (2.40 ± 0.51 )％ in control group,(5.62 ±0.50)％ in IR,(7.13±0.83)％ in CpG OND1826 0.15 mg,(11.63±1.06)％ in CpG OND1826 0.3 mg,(19.13 ±0.83)％ in CpG OND1826 0.45 rag,( 12.88±0.83)％ in CpG OND1826 0.15 mg+ IR,(20.57±2.37)％ in CpG OND1826 0.3 mg+ IR,and (28.17 ±3.31)％ in CpG OND1826 0.45 mg + IR group,and thus the apoptosis rate of every therapy group was higher than that in control ( t=11.15,7.91,17.82,39.48,24.73,16.61 and 17.05,P＜0.05).The apoptosis rates of CpG ODN1826 plus X-ray irradiation group were significantly higher than those in IR alone ( t =13.78,15.08 and 17.47,P＜0.05 ) or CpG ODN group (t=18.53,9.66and7.51,P＜0.05).Conclusions CpG ODN1826 can dramatically increase the efficiency of radiotherapy by inhibiting tumor growth and promoting lumor apoptosis.

Anti-tumor Effect of Combined Betacarotene with X-irradiation in the Mouse Fibrosarcoma : Cytotoxicity and Tumor Growth Delay / 대한방사선종양학회지

PURPOSE: To investigate whether combined beta-carotene with X-irradiation has more enhanced radition response than X-irradiation or not, we performed a experiment about in vitro cytotoxicity of beta-carotene and/or X-irradiation in the fibrosarcoma cells, tumor growth delay of combined beta-caroten with/or X-irradiation in the mouse fibrosarcoma. MATERIALS AND METHODS: 2% emulsion of beta-carotene was serially diluted and used. X-irradiation was given by 6 MeV linear accelerator. The cytotoxicity of beta-carotene in vitro was evaluated from clonogenic assay. To compare the cytotoxicity between combined beta-carotene with X-irradiation and X-irradiation group, 2 mg/ml of beta-carotene was contacted to fibrosarcoma (FSaII) cells for 1 hour before X-irradiation. For the tumor growth delay, single 20 Gy was given to FSaII tumor bearing C3H/N mice whic was classified as beta-crotene with X-irradiation group (n=6) and X-irradiation alone group (n=5). 0.2 ml of 20 mg/kg of beta-carotene were i.p. injected to mice 30 minute before X-irradiation in the beta-crotene with X-irradiation group. The tumor growth delay defined as the time which reach to 1,000 mm3 of tumor volume. RESULT: (1) Cytotoxicity in vitro; 1) survival fraction at beta-carotene concentration of 0.002, 0.02, 0.2 and 2 mg/ml were 0.69+/-0.07, 0.59+/-0.08, 0.08+/-0.008 and 0.02+/-0.006, respectively. 2) each survival fraction at 2, 4, 6 and 8 Gy in the 2 mg/ml of beta-carotene + X-irradiation group were 0.13+/-0.05, 0.03+/-0.005, 0.01+/-0.002 and 0.009+/-0.0008, respectively. But each survival fraction at same irradiation dose in the X- irradiation group were 0.66+/-0.05, 0.40+/-0.04, 0.11+/-0.01 and 0.03+/-0.006, respectively( p0.05). CONCLUSION: The contact of beta-caroten to FSaII cells showed mild cytotoxicity which was increased according to concentration. The cytotoxicity of combined beta-carotene with X-irradiation more increased than that of X-irradiation, additionaly. And there was significant difference of cytotoxicity between two groups. But there were no significant difference of the growth delay of fibrosarcoma between two groups.

Enhancing effect of CpG on sensitivity of Lewis lung cancer to X-ray radiation in mice / 中国肿瘤生物治疗杂志

Objective: To explore the role of cytosine-phosphate-guanine oligodeoxynucleotide(CpG ODN)in enhan- cing the radiosensitivity to X-ray in mouse with Lewis lung cancer.Methods: The tumor-bearing mouse model was in- duced by injevting Lewis lung cancer cells into the right infra-axillary dermis.Thirty-two C57BL/6J mice were evenly ran- domized into 4 groups.Group A: the control group;Group B: the X-Ray radiation group;Group C: the CpG group; Group D: the CpG plus X-Ray radiation group.Group B was treated with X-Ray radiation only(3 Gy/F,on day 1,3,5, 8,10,and 12;the total dose was 18 Gy);group C was administered with CpG ODN 0.05 mg on day 1,3,5,8,10, and 12;group D was administered with CpG ODN 6h before X-ray radiation.The tumor growth and tumor growth delay (TGD)were observed in all groups.Meanwhile,the pathological change of the tumor tissue was observed with H-E staining method and the apoptosis of tumor cells were examined with the method of TUNEL.Results: The Lewis hmg cancer-bearing model was successfolly established in mice.The tumor volumes of the treatment groups were smaller than that in lhe control group(P

Antitumor effect of Ganoderma lucidum: Cytotoxicity and Tumor Growth Delay(1) / 대한치료방사선과학회지

PURPOSE: To investigate the effect of aqueous extract of Ganoderma lucidum(G.I.) on the survival of tumor cells in vitro and on the growth of tumors in vivo. MATERIALS AND METHODS: Dried G.I. was made into powder, extracted with distilled water, filtered and diluted from a maximum concentration of 100 mg/ml in sequence. The cytotoxicity of G.O. in vitro was evaluated from its ability to reduce the clonogenicity of SCK tumor cells. For the tumor growth delay study, about 2' 105 of SCK tumor cells were subcutaneously inoculated in the legs of A/J mice. The first experimental group of mice were injected i.p. with 0.2ml of 250 mg/kg of G/I. From the first day after tumor inoculation for 10 days. The second experimental group of mice were injected i.p. with 0.2ml of 250 mg/kg of G.I. either once a day for 10 days or twice a day for 5 days beginning from the 7th day after tumor inoculation. RESULTS: 1. Cytotoxicity in vitro; survival fraction, as judged from the curve, at G.I. concentration of 0.5,1,5,10,25,50 and 100 mg/ml were 1.0, 0.74+/-0.03, 0.18+/-0.03, 0.15+/-0.02, 0.006+/-0.002, 0.015 and 0.0015, respectively. 2. Tumor growth delay in vivo; a) the time required for the mean tumor volume to grow to 1,000mm3 was 11 days in the control group and 14 days in the experimental group. b) the time required for tumor volume to increase 4 times was 11 days in the control group while it was 10.5 and 12 days in the groups injected with G.I. once a day and twice a day from the 7th day after tumor inoculation respectively. CONCLUSION: Aqueous extracts of G.I. showed a marked cytotoxicity on the SCK mammary cells in vitro. Tumor growth delay was statistically significant when G.I. injection was started soon after tumor inoculation, but it was not significant when injection was started after the tumors were firmly established.