Objective: To explore the role of telomerase activity detected in biopsy samples for evaluating the efficacy of lapa- roscopic radiofrequency ablation (RFA) therapy in patients with hepatocellular carcinoma (HCC) and ...Objective: To explore the role of telomerase activity detected in biopsy samples for evaluating the efficacy of lapa- roscopic radiofrequency ablation (RFA) therapy in patients with hepatocellular carcinoma (HCC) and liver cirrhosis. Methods: From August 2001 to October 2004, 34 cirrhotic patients with HCC were treated by laparoscopic RFA under general anesthe- sia. A total of 34 tumors, with a mean maximum tumor diameter of 4.0 ± 1.0 cm, were all located on the liver surface or adja- cent to the gallbladder. Laparoscopic ultrasound-guided core biopsy for liver lesions was performed before and immediately after RFA therapy. In these biopsy samples, telomerase activity was detected by the ELISA-based telomeric repeat amplifica- tion protocol (ELISA-TRAP) assay, and pathological examination was routinely performed. Results: Laparoscopic RFA was successfully performed in all the 34 patients. A complete tumor necrosis was achieved in all patients on the contrast-enhanced helical CT scanning one month after laparoscopic RFA. The positive rates of telomerase activity and histopathologic diagnosis in biopsy samples were 91.2% (31/34) and 100% (34/34) respectively before RFA, and 26.5% (9/34) and 0% respectively after RFA. During a median follow-up period of 35 months (range, 18–51 months), the rates of local tumor recurrence at the ablation sites in post-RFA telomerase-positive and negative patients were 88.9% (8/9) and 4% (1/25) respectively (P < 0.01), and the rates of distant recurrence within the livers were 0% (0/9) and 12% (3/25) respectively (P > 0.05). Conclusion: For cirrhotic patients with HCC treated by laparoscopic RFA, detection of telomerase activity in biopsy samples may be useful for evaluating the therapeutic efficacy of RFA and predicting postoperative local tumor recurrence.展开更多
Objective: The aim of the study was to construct a stable strain of recombined attenuated Salmonella typhimurium expressing NK4 gene, and observe the effect of the strain on the metastatic potentiality of HepG2 cells...Objective: The aim of the study was to construct a stable strain of recombined attenuated Salmonella typhimurium expressing NK4 gene, and observe the effect of the strain on the metastatic potentiality of HepG2 cells. Methods: The NK4 cDNA was isolated from PCAGGS/hNK4 plasmid by PCR, and subcloned into eukaryotic expression vector pcDNA4. The recombinant plasmid was electro-transferred into attenuated Salmonella typhimurium Ty21a to obtain the recombinant strain encoding NK4 gene (TPN). Simultaneously, the recombinant attenuated Salmonella typhimurium carrying GFP gene (TPG) was also constructed. After the TPG and TPN were transferred into HepG2 cells, the transfection rate and the expression level of NK4 protein were detected by flow cytometry and ELISA, and the effects of expression product on the proliferation and migration of HepG2 and angiogenesis were observed. Results: The TPN and TPG were successfully constructed. Fortyeight hours after transfection with TPG, the infection rate was 82.58% ± 1.74%, and the expression level of NK4 protein in supernatant was (181.5 ± 11.7) ng/6 × 10^5 cells. The supematant had obviously depressant effect on the proliferative activity of HepG2 cells (P 〈 0.05), and could obviously restrain the hepatocyte growth factor-mediated migration of tumor cells (P 〈 0.01). The inhibitory effect of the expression product on the tumor angiopoiesis was obviously observed (P 〈 0.05), without a dosage-effect relation. Conclusion: The TPN could effectively transfer tumor cells in vitro and express interest NK4 protein. The expression product could effectively inhibit the proliferation and migration of hepatocellular carcinoma cells and the tumor angiopoiesis.展开更多
基金National Basic Research Program (973 Program) of China(No. G20000057001)National Natural Science Foundation of China (No.30471994)+1 种基金Shanghai Pujiang Talent Program (No. 05PJ14010)Major Basic Research Project of Shanghai (No. 04DZ14006)
文摘Objective: To explore the role of telomerase activity detected in biopsy samples for evaluating the efficacy of lapa- roscopic radiofrequency ablation (RFA) therapy in patients with hepatocellular carcinoma (HCC) and liver cirrhosis. Methods: From August 2001 to October 2004, 34 cirrhotic patients with HCC were treated by laparoscopic RFA under general anesthe- sia. A total of 34 tumors, with a mean maximum tumor diameter of 4.0 ± 1.0 cm, were all located on the liver surface or adja- cent to the gallbladder. Laparoscopic ultrasound-guided core biopsy for liver lesions was performed before and immediately after RFA therapy. In these biopsy samples, telomerase activity was detected by the ELISA-based telomeric repeat amplifica- tion protocol (ELISA-TRAP) assay, and pathological examination was routinely performed. Results: Laparoscopic RFA was successfully performed in all the 34 patients. A complete tumor necrosis was achieved in all patients on the contrast-enhanced helical CT scanning one month after laparoscopic RFA. The positive rates of telomerase activity and histopathologic diagnosis in biopsy samples were 91.2% (31/34) and 100% (34/34) respectively before RFA, and 26.5% (9/34) and 0% respectively after RFA. During a median follow-up period of 35 months (range, 18–51 months), the rates of local tumor recurrence at the ablation sites in post-RFA telomerase-positive and negative patients were 88.9% (8/9) and 4% (1/25) respectively (P < 0.01), and the rates of distant recurrence within the livers were 0% (0/9) and 12% (3/25) respectively (P > 0.05). Conclusion: For cirrhotic patients with HCC treated by laparoscopic RFA, detection of telomerase activity in biopsy samples may be useful for evaluating the therapeutic efficacy of RFA and predicting postoperative local tumor recurrence.
基金Supported by a grant from the National Natural Science Foundation of China (No.30772572)two research grants from Postdoctors in China (No.20060390192,200801243)+1 种基金a grant from the Natural Science Foundation of Gansu Province (No.0803RJZA061)a research grant for science from Gansu Provincial Sci. & Tech. Department (No.0708NKCA128)
文摘Objective: The aim of the study was to construct a stable strain of recombined attenuated Salmonella typhimurium expressing NK4 gene, and observe the effect of the strain on the metastatic potentiality of HepG2 cells. Methods: The NK4 cDNA was isolated from PCAGGS/hNK4 plasmid by PCR, and subcloned into eukaryotic expression vector pcDNA4. The recombinant plasmid was electro-transferred into attenuated Salmonella typhimurium Ty21a to obtain the recombinant strain encoding NK4 gene (TPN). Simultaneously, the recombinant attenuated Salmonella typhimurium carrying GFP gene (TPG) was also constructed. After the TPG and TPN were transferred into HepG2 cells, the transfection rate and the expression level of NK4 protein were detected by flow cytometry and ELISA, and the effects of expression product on the proliferation and migration of HepG2 and angiogenesis were observed. Results: The TPN and TPG were successfully constructed. Fortyeight hours after transfection with TPG, the infection rate was 82.58% ± 1.74%, and the expression level of NK4 protein in supernatant was (181.5 ± 11.7) ng/6 × 10^5 cells. The supematant had obviously depressant effect on the proliferative activity of HepG2 cells (P 〈 0.05), and could obviously restrain the hepatocyte growth factor-mediated migration of tumor cells (P 〈 0.01). The inhibitory effect of the expression product on the tumor angiopoiesis was obviously observed (P 〈 0.05), without a dosage-effect relation. Conclusion: The TPN could effectively transfer tumor cells in vitro and express interest NK4 protein. The expression product could effectively inhibit the proliferation and migration of hepatocellular carcinoma cells and the tumor angiopoiesis.