Oxidative damage theory is currently one of the predominant theories on the mechanisms of aging. Previous research has shown that antioxidants can extend the lifespan in the model organism by scavenging free radicals,inducing the expression of stress related genes and hormesis. However, recent studies have suggested that these pharmaceuticals may cause serious side effects,such as promoting oxidation,increasing the risk of cancer,and destroying the metabolic balance. The low absorption and targeting property also limit the efficiency of most antioxidants. As a result ,the correlation between antioxidants and lifespan extension remains to be demonstrated. We reviewed the research progress in the field of lifespan extension by antioxidants in recent years and provided references for future research in related areas.

To investigate the role of Egr-1 in the carcinogcnestic process of hepatocellular carcinoma (H-CC). Methods Expression of Egr-1 gene in HCC tissues were detected by in situ hybridization and immunohistochemistry. Human breast andmouse liver and brain tissues were used for control. ResultsLittle or no Egr-1 transcription was detected both in HCC tissues and in their normal counterparts. High transcription of Egr-1 was detected in the LCD and atrophic-like liver plate of HCC tissues. Protein expression of Egr-1 gene was consistent with mRNA transcription. High expression of Egr-1 protein was also detected in normal breast and mouse brain tissues. ConclusionsLittle or no expression of Egr-1 may play a role in the deregulation of normal growth in the carcinogenestic process of HCC. The differences of Egr-1 expression among liver cells, breast epithelia and mouse brain tissues might be associated with their different ways of proliferation and differentiation in different cell types.

Objective To investigate the differentially expressed genes of primary esophageal squamous cell carci-noma and of normal esophageal mucosa. Methods LCM-GMA-cDNA microarray was used to detect the mRNA from both the primary carcinoma and the corresponding esophageal epithelium in 15 cases of human esophageal squamous cell carcinoma (ESCC). After high-stringent washing, the cDNA microarray was scanned for the fluores-cent signals. Results Among the 886 target genes, 34 genes had significant difference in Ⅰ / Ⅱ and Ⅲ/Ⅳ group. Cell cycle regulators possibly promoting the growth of tumor cells were highly expressed in the early stages of ESCC, whereas adhesion molecules and extracellular matrix-related molecules possibly promoting invasiveness increased in the later stages. Conclusion More than one gene contributed to esophageal cancer. The profiles of gene expression will bring us chance to understanding the molecular mechanism of tumor progression and to support clinical treat-ment.

AIM: To construct a mouse IFN-? expression vector and observe the antitumor effects of mouse peritoneal macrophages transfected with IFN-? in vivo and in vitro. METHODS: The IFN-? mRNA was amplified by RT-PCR. The open reading frame of mouse IFN-? gene was recombinanted with eukaryotic expression vector pcDNA3.1 through subcloning. Mouse peritoneal macrophages were transfected with recombinant vector pcDNA3.1-IFN-?. The expression of INF-? mRNA was measured by RT-PCR. Another group of peritoneal macrophages were cultured with the culture medium from pcDNA3.1-IFN-? transfecting groups, and its antitumor effect was measured by MTT. pcDNA3.1-IFN-? plasmid was peritoneally injected inte mouse with tumor. The appearance of ascites of pcDNA3.1-IFN-? plasmid injected mice and survival time were observed. RESULTS: The mouse IFN-? expression vector pcDNA3.1-IFN-? was constructed. The sequence was demonstrated to be the same as on GenBank. The recombinant vector was introduced into mouse peritoneal macrophages. IFN-? mRNA was detected by RT-PCR. The supernatant from cultured macrophages transfected with pcDNA3.1-IFN-? plasmid stimulated the antitumor effects of the macrophages without transfection. The appearance of ascites in pcDNA3.1-IFN-? plasmid injected mouse was delayed and survival time was longer than that in other groups. CONCLUSION: We have successfully constructed the mouse IFN-? expression vector pcDNA3.1-IFN-?. Mouse peritoneal macrophages transfected with pcDNA3.1-IFN-? have antitumor effects in vivo and in vitro.

The differentially expressed genes between esophageal squamous cell carcinoma (ESCC) with or without lymphatic metastasis were investigated by gene chip, and the lymphatic metastasis-associated genes were screened out. Expression array was used to detect the mRNA from both the primary carcinoma and the corresponding esophageal epithelium in 15 cases of human ESCC. The lymphatic metastasis-associated genes were screened by bioinformatics between ESCC with or without lymphatic metastasis. The results showed that 43 (4.85 %) genes significantly differed between the ESCC with and without lymphatic metastasis (P<0.05), of which 18 (2.03 %)were upregulated and 25 (2.82 %) down-regulated. The up-regulated genes were involved in cell adhesion molecules and cell membrane receptors and the down-regulated genes were mostly cell cycle regulators and intracellular signaling molecules. It was suggested that lymphatic metastasis-associated genes were screened by gene chip, which was helpful to understand the molecular mechanism of ESCC lymphatic metastasis and lymphatic metastasis-associated genes might be used as diagnostic markers and therapeutic targets for lymphatic metastasis.

Objective To study the effects of Alternariol(AOH) on DNA polymerase ?(DNA POL?)expression in NIH3T3 cells.Methods RT-PCR,Immunocytochemistry and Western blot were used to detected mRNA and the protein levels of DNA POL? in NIH3T3 cell line induced by AOH.Results The expression of DNA POL? in NIH3T3 cells contaminated by AOH was significantly higher than that in the control group(P

Objective To investigate the etfect of microenvironment simulated by colon carcinoma homogenate supernatant on the differentiation and development of human dendritic ceils (DCs), and to investigate the function of vascular endothelial growth factor A (VEGF-A) during this process . Methods Fresh colon carcinoma and peri-cancer tissues were collected to prepare homogenate supernatant. The pe-ripberal blood mononuclear cells were isolated and cultured with 1640 medium including rhGM-CSF and rhIL-4. Then the colon carcinoma homogenate supernatant, peri--carcinoma homogenate supernatant and VEGF-A were added to the cultures at day 2. Antigen of colon carcinoma cell line SW620 was added at day 4 and lipopolysaccharide (LPS) was added at day 6. DCs were collected at day 8 for further study. The con-tent of VEGF-A was tested by ELISA. The morphology and the immunopbenotype of DCs were checked by microscope and flow cytometry, respectively. The expression of CDIa was tested by RT-PCR, and the prolif-eration and killing rate of T cell was measured by CCK-8. Results The content of VEGF-A in the homoge-nate supernatant of colon carcinoma was significantly higher than that of the peri-carcinoma (P ＜ 0. 05). Compared with normal DCs, the cell morphology of colon carcinoma homogenate aupernatant group was in-hibited, and the cell number was decreased. Besides, the positive expression rate of DC surface markers de-creased (P ＜ 0.01). The capacity of mixed lymphocyte reaction (MLR) and killing capacity of T cells de-creased(P ＜0.01). However, there was almost no difference between VEGF-A group and normal DCs on the cell morphology and cell number, and VEGF-A had no obvious inhibition on the expression of DCs sur-face markers (P ＞ 0.05). But VEGF-A group had significantly inhibitory effect on the MLR and T cells kill-ing. Conclusion The tumor microenvironment simulated by the colon carcinoma homogenate supernatant obviously has inhibitory effect on the differentiation and function of DCs, and VEGF-A has the inhibitory effect on DC function, but the inhibitory effect is not through the inhibition of the expression of DC costimu-lators.

AIM: To prepare the vaccine of DCs(pcDNA3-hCEA) and observ the immunity effect of the DCs(pcDNA3-hCEA) inoculating on CT26(hCEA +) loaded in BALB/c mice. METHODS: DCs were generated from bone marrow in the presence of rmGM-CSF and rmIL-4. A new recombinant plasmid, pcDNA3-hCEA, reformed with inserting a 2.4 kb human CEA cDNA into pcDNA3. DC vaccine was prepared by transfection with pcDNA3-hCEA using lipofectamine. CEA mRNA expressed in DCs(pcDNA3-hCEA) was confirmed by RT-PCR, CEA expression level was detected with RIA method, and CEA specific CTL was induced in vitro . After vaccination of DCs(pcDNA3-hCEA), the survival time of the BALB/c mice challenged with critical loading CT26(hCEA +) was observed. RESULTS: G418 test showed that about 14% DCs were transfected with pcDNA3-hCEA. And CEA mRNA and protein could be detected respectively by RT-PCR and RIA in the genetically modified DCs. Furthermore, the DCs coud be targeted by specific CTL, the survival time of the mice challenged with CT26(hCEA +) was prolonged 1-4 weeks. CONCLUSION: These results demonstrate that specific antitumor immune responses could be induced efficiently by vaccination of DCs(pcDNA3-hCEA), which is transfected eukaryotic expression vector encoding tumor antigen gene.

The differentially expressed genes between esophageal squamous cell carcinoma (ESCC)with or without lymphatic metastasis were investigated by gene chip, and the lymphatic metastasisassociated genes were screened out. Expression array was used to detect the mRNA from both the primary carcinoma and the corresponding esophageal epithelium in 15 cases of human ESCC. The lymphatic metastasis-associated genes were screened by bioinformatics between ESCC with or without lymphatic metastasis. The results showed that 43 (4.85%) genes significantly differed between the ESCC with and without lymphatic metastasis (P＜0.05), of which 18(2.03%)were upregulated and 25 (2.82 %) down-regulated. The up-regulated genes were involved in cell adhesion molecules and cell membrane receptors and the down-regulated genes were mostly cell cycle regulators and intracellular signaling molecules. It was suggested that lymphatic metastasis-associated genes were screened by gene chip, which was helpful to understand the molecular mechanism of ESCC lymphatic metastasis and lymphatic metastasis-associated genes might be used as diagnostic markers and therapeutic targets for lymphatic metastasis.

To screen the genes associated with esophageal cancer, a cDNA microarray technique was established and used for the analysis of the gene expression profile in human esophageal cancer cell line ECa109. The results showed that 107 (12.08%) genes differentially expressed among 886 target genes were identified between ECa109 cell line and normal human esophageal epithelial cells (HEEC), of which 51 (5.76%) were up-regulated and 56 (6.32%) down-regulated. Two genes were validated by quantitative RT-PCR (Q-RT-PCR) and the results were identical. The RNA amplification technique based-T7 RNA polymerase was established. The gene expression profile revealed better consistency between the amplified samples and those without amplification by T7 RNA polymerase, which provides a method for studying the profile of minute quantities of tumor cells in primary esophageal cancers. And the preliminary study on differential expression gene profile also enables us to have an understanding of the pathogenesis and pathomechanism of esophageal cancer.
Carcinoma, Squamous Cell ; genetics ; pathology ; Esophageal Neoplasms ; genetics ; pathology ; Gene Expression Profiling ; methods ; statistics & numerical data ; Gene Expression Regulation, Neoplastic ; Humans ; Oligonucleotide Array Sequence Analysis ; methods ; Reverse Transcriptase Polymerase Chain Reaction ; Tumor Cells, Cultured