In the present experiment,an inhibitor of superoxide dismutase(SOD),diethyldithiocarbamate(DETC),was used to decrease SOD activity for the observation of the relation between SOD activity and carcinogenesis and the ex...In the present experiment,an inhibitor of superoxide dismutase(SOD),diethyldithiocarbamate(DETC),was used to decrease SOD activity for the observation of the relation between SOD activity and carcinogenesis and the expression of P53 protein in vivo.144 Wistar rats were used for the Present study.The results showed that the SOD activity reduction by DETC resulted markedly in the promotion of the carcinogenesis and the expression of P53 protein in the lung tissues,but the increase of SOD activity by the addition of plus SOD inhibited the pathological changes significantly.The frequency of the pathological lesions and Positive P53 expression are 36/42 and 8/42 in the animals without DETC and SOD:16/52 and 4/52 in the animals with SOD and 46/50 and 26/50 in the animals with DETC respectively.The results reported in this Paper suggest that:(1) the decrease of SOD activity enhanced the carcinogenesis induced by chemical carcinogen;(2) P53 gene may be associated with the process of tumorigenesis;and(3) at the same time the abnormal expression of P53 protein may be associated with the transition from premalignant lesions to carcinoma.展开更多
Background Gene therapy and epigenetic therapy have gained more attention in cancer treatment. However, the effect of a combined treatment of gene therapy and epigenetic therapy on head and neck squamous cell carcinom...Background Gene therapy and epigenetic therapy have gained more attention in cancer treatment. However, the effect of a combined treatment of gene therapy and epigenetic therapy on head and neck squamous cell carcinoma have not been studied yet. To study the mechanism and clinical application, human laryngeal carcinoma cell （Hep-2） tumor-bearing mice were used. Methods A xenograft tumor model was established by the subcutaneous inoculation of Hep-2 cells in the right armpit of BALB/c nu/nu mice. The mice with well-formed tumor were randomly divided into six groups. Multisite injections of rAd-p53 and/or 5-aza-dC were used to treat tumor. Tumor growth was monitored by measuring tumor volume and growth rate. p53 and E-cadherin protein levels in tumor tissues were detected by immunohistochemical staining. The mRNA levels were monitored with FQ-PCR. Results Gene therapy was much more effective than single epigenetic therapy and combined therapy. The gene therapy group has the lowest tumor growth rate and the highest expression levels of p53 and E-cadherin. Conclusions The combined treatment of gene and epigenetic therapy is not suggested for treating head and neck carcinoma, because gene therapy shows an antagonistic effect to epigenetic therapy. However, the mechanisms of action are still unclear.展开更多
文摘In the present experiment,an inhibitor of superoxide dismutase(SOD),diethyldithiocarbamate(DETC),was used to decrease SOD activity for the observation of the relation between SOD activity and carcinogenesis and the expression of P53 protein in vivo.144 Wistar rats were used for the Present study.The results showed that the SOD activity reduction by DETC resulted markedly in the promotion of the carcinogenesis and the expression of P53 protein in the lung tissues,but the increase of SOD activity by the addition of plus SOD inhibited the pathological changes significantly.The frequency of the pathological lesions and Positive P53 expression are 36/42 and 8/42 in the animals without DETC and SOD:16/52 and 4/52 in the animals with SOD and 46/50 and 26/50 in the animals with DETC respectively.The results reported in this Paper suggest that:(1) the decrease of SOD activity enhanced the carcinogenesis induced by chemical carcinogen;(2) P53 gene may be associated with the process of tumorigenesis;and(3) at the same time the abnormal expression of P53 protein may be associated with the transition from premalignant lesions to carcinoma.
文摘Background Gene therapy and epigenetic therapy have gained more attention in cancer treatment. However, the effect of a combined treatment of gene therapy and epigenetic therapy on head and neck squamous cell carcinoma have not been studied yet. To study the mechanism and clinical application, human laryngeal carcinoma cell （Hep-2） tumor-bearing mice were used. Methods A xenograft tumor model was established by the subcutaneous inoculation of Hep-2 cells in the right armpit of BALB/c nu/nu mice. The mice with well-formed tumor were randomly divided into six groups. Multisite injections of rAd-p53 and/or 5-aza-dC were used to treat tumor. Tumor growth was monitored by measuring tumor volume and growth rate. p53 and E-cadherin protein levels in tumor tissues were detected by immunohistochemical staining. The mRNA levels were monitored with FQ-PCR. Results Gene therapy was much more effective than single epigenetic therapy and combined therapy. The gene therapy group has the lowest tumor growth rate and the highest expression levels of p53 and E-cadherin. Conclusions The combined treatment of gene and epigenetic therapy is not suggested for treating head and neck carcinoma, because gene therapy shows an antagonistic effect to epigenetic therapy. However, the mechanisms of action are still unclear.
