AIM: To investigate the mechanism by which IL-6 is involved in cancer prognosis, and further to demonstrate the relationship between IL-6 and tumor-associated antigens such as CA15-3, CEA and CA125 in breast cancer. METHODS: In the present study, we transfected an exogenous IL-6 gene into the MCF-7 cells. Secretion of CA15-3, CEA and CA125 into the culture media were measured by Enzyme Linked Immunosorbent Assay (ELISA). RESULTS: After a 72 hours in culture, the amount of IL-6 in the media of pCI-neo-IL-6-transfected MCF-7 cells (338.5±22.6 pg/106 cells) was significantly higher than that of non-transfected MCF-7 cells (25.4±4.6 pg/106 cells, P＜0.01, paired t-test), or pCI-neo-transfected MCF-7 cells (19.6±3.0 pg/106 cells, P＜0.01, paired t-test). The levels of CA15-3, CEA and CA125 secreted by the pCI-neo-IL-6-transfected MCF-7 cells were significantly higher than that of the parental MCF-7 cells or pCI-neo-transfected MCF-7 cells. The specific IL-6 antibody could decrease the expression of CA15-3, CEA and CA125 in both the MCF-7 cells and the IL-6 cDNA-transfected MCF-7 cells. CONCLUSION: Transfer of IL-6 gene augments tumor-associated antigens of human breast cancer cells. The association of elevated IL-6 concentration with a poor prognosis in cancer patients may partially be the result of increased expression of tumor-associated antigens by IL-6.

Objective To investigate the effect of Caveolin-1 on extracellular regulated protein kinases of rabbit carotid artery anastomotic restenosis.Methods 40 New Zealand white rabbits were randomly divided into normal control group,carotid artery end to end anastomosis surgical group,empty vector transfection on the site of anastomosis group and Caveolin-1 transfected group.Left carotid artery endto-end anastomosis was performed,and the mixture of Caveolin-1 plasmid and liposome lipofectin 2000 (transfected group) or empty plasmid and lipofectin 2000 mixture (empty vector group) were transfected on anastomosis.Specimens were taken at 7 d after surgery for Western blot and RT-PCR to detect the expression of protein and mRNA.Specimens were taken for HE staining at 28 d to observe the proliferation of intima,and measured the ratio of intima/media area by Image-Pro Plus 6.0 software.Results Compared with surgical group,the ratio of intima/media area in Caveolin-1 transfected group decreased by about 50％.Compared with surgical group and empty vector group,the Caveolin-1 mRNA expression and protein activity significantly increased (t =36.59,P ＜ 0.01) ; the ERK1/2 mRNA expression and protein activity significantly decreased on rabbit carotid artery anastomotic site in Caveolin-1 transfected group (t =32.64and 7.27,P ＜ 0.01).Conclusions Caveolin-1 inhibits anastomotic restenosis possibly by regulating the activation of ERK.

Objective To observe the regulatory role of long non-coding RNA HIF1A-AS1 on the autophagy of pancreatic cancer PANC1 cells induced by hypoxia.Methods The pancreatic cancer PANC1 cells were cultured in a three-gas incubator filled with hypoxic gas mixture (94% N2,5% CO2,1% O2) for 3, 6, 12, 24, 36 and 48 h.HIF1A-AS1 overexpression and low expression PANC1 cells were obtained by the infection of recombinant adenovirus carrying HIF1A-AS1 and the transfection of HIF1A-AS1 targeting siRNA by liposome, and routinely cultured PANC1 cells served as control.The expression of HIF1A-AS1 of PANC1 cells was detected by real-time quantitative PCR after being cultured in hypoxia-induced condition for 24 h.The apoptosis rate was detected by flow cytometry.The autophagy related proteins Beclin 1 were detected by western blot.Results The expression of HIF1A-AS1 in hypoxic cells was increased as the hypoxic time increased since 6 h and peaked at 36 h, which was significantly higher than that in control group (P<0.01).HIF1A-AS1 relative expression in HIF1A-AS1 overexpression and low expression PANC1 cells was 4.49±0.53 and 0.49±0.07, which were normalized to that of control group with the relative expression of 1.Control group had lower HIF1A-AS1 expression than HIF1A-AS1 overexpression PANC1 cells but higher HIF1A-AS1 in HIF1A-AS1 low expression PANC1 cells, and the differences were statistically significant (P<0.01).The cell apoptosis rate of control, HIF1A-AS1 overexpression and low expression PANC1 cells was (8.27±1.28)%, (6.56±1.49)% and (19.9±2.34)% after 24 h hypoxic culture.Control group had higher HIF1A-AS1 expression than HIF1A-AS1 overexpression PANC1 cells but lower HIF1A-AS1 in HIF1A-AS1 low expression PANC1 cells, and the differences were statistically significant (P<0.01).The expression of Beclin 1 protein was protein 1.05±0.11, 1.29±0.19 and 0.38±0.18, respectively.Control group had lower Beclin 1 expression than HIF1A-AS1 overexpression PANC1 cells but higher Beclin 1 in HIF1A-AS1 low expression PANC1 cells, and the differences were statistically significant (P<0.01).Conclusions HIF1A-AS1 can promote autophagy of pancreatic cancer PANC1 cells induced by hypoxia and participate in the pathogenesis and metastasis of pancreatic cancer.

Objective To investigate the effect of caveolin-1 on rabbit carotid artery anastomotic stenosis and its relationship with TNF-α.Methods 40 New Zealand white rabbits were randomly divided into normal group,surgical group,empty vector group and caveolin-1 transfecting group.Carotid artery end-to-end anastomosis was done in the rabbits except these in normal group.Five specimens were randomly taken on day 7 after surgery for Westem blot to detect the expression of caveolin-1 and TNF-α; The rest specimens were taken for HE staining at fourth week.The ratio of intima/media area were measured by Image-Pro Plus 6.0 software in order to observe the proliferation of intima.Results Compared with normal group,in surgical group intimal proliferation was significant,the intima/media ratio was significantly higher (P ＜ 0.05) ; Compared with surgical group,in caveolin-1 transfected group neointimal proliferation was not obvious,the intima/media ratio decreased (P ＜ 0.05).Western blot showed that:compared with the surgical group,caveolin-1 expression in transfected group was significantly higher (P ＜ 0.05) ; compared with normal group,the TNF-α expression in surgical group increased (t:41.28,P ＜ 0.05) ; Compared with surgical group,TNF-α expression in transfected group decreased significantly (t:36.37,P ＜ 0.05).Conclusions Caveolin-1 inhibits vascular anastomotic stenosis,possibly by down-regulating TNF-α expression.

Objective To investigate the role and potential mechanism of high mobility group box-1 protein (HMGB1) on improving the chemosensitivity of gemcitabine-resistant pancreatic cancer PANC1 ceils.Methods Gemcitabine-resistant pancreatic cancer PANC1 (PANC1-GR) cell line was established by using increased gradient concentration of gemcitabine.The si-HMGB1-PANC1 and si-HMGB1-PANC1-GR cells were established by the transfection with HMGB1 siRNA using liposome.The 50％ inhibitory concentration (IC50) and Resistance index (RI) of gemcitabine in 4 PANC1 cell lines with or without HMGB1 siRNA transfection were determined and calculated by CCK-8 assay.Western blot assay was used to detect the protein expression of HMGB1 in PANC1 and PANC1-GR cells and the expression of autophagy marker protein Beclin1 in the 4 PANC1 cell lines.Flow cytometry assay was used to evaluate the apoptosis rate of 4 pancreatic caner cell lines.Results The gemcitabine-resistant pancreatic cancer cell line PANC1-GR was successfully established,which could grow stably and passage in media with 100 μmol/L gemcitabine.The IC50 of gemcitabine in PANC1,PANC1-GR,si-HMGB1-PANC1,and si-HMGB1-PANC1-GR cells lines were (4.7 ±0.4) μmoL/L,(166.5 ± 13.6) μmol/L,(3.2 ± 0.3) μmol/L,and (52.4 ± 8.4) μmol/L,respectively.The IC50 in PANC1-GR wassignificantly higher than that in PANC1,while the IC50 in the transfected cells was significantly lower than that in untransfected cells,and the differences were both statistically significant (bothP ＜ 0.01).The RI value of gemcitabine in transfected and untransfected PANC1-GR cells was 35.4 and 16.4.The relative protein levels of HMGB1 in PANC1 and PANC1-GR were 0.17 ± 0.08 and 0.38 ± 0.11.The expression of HMGB1 in PANC1-GR was obviously higher than that in PANC1,and the difference was statistically significant (P＜0.01).The relative protein levels of Beclin1 in PANC1,PANC1-GR,si-HMGB1-PANC1 and siHMGB1-PANC1-GR cells were 2.68 ± 0.23,3.28 ± 0.15,0.68 ± 0.23 and 0.78 ± 0.11,which in two transfected cells was greatly lower than those in untransfected cells.The apoptosis level was (34.58± 3.14)％,(79.56±3.58)％,(19.41± 1.53)％,and (34.57±2.94)％.The apoptosis level in the 2 transfected cell lines were significantly higher than those in the 2 untransfected cell lines,and the differences were both statistically significant (P ＜ 0.01).Conclusions The inhibition of HMGB1 could improve the chemosensitivity of gemcitabine in pancreatic cancer PANC1 cells,which might be mediated by the activation of autophagy.

Objective To make a better understanding of the molecular mechanisms involved in recurrence and metastasis of the hepatocellular carcinoma (HCC), some invasion related oncogenes, and growth factors have been investigated. Methods The studies were seperately carried out, the results of which were summarized in this article with relation to tumor size and invasiveness of HCC.Results The aberration rates of p53 and CDKN2 in HCC were 45.9% and 36.4% respectively, which were higher in invasive HCC compared with non-invasive HCC. H-ras expression was positive in 29.3% of HCC, which was associated with recurrence and extrahepatic metastasis of HCC. Intralesional injection of H-ras antisense gene markedly inhibited the tumor growth and metastasis of HCC in nude mice. The positive rates of transforming growth factor (TGF)-alpha, epidermal growth factor receptor (EGFR) and c-erbB-2 were 45.7%, 47.1% and 92.3% respectively. The expression of EGFR was closely related to TGF-alpha, which was related to HCC recurrence. But no obvious difference of TGF-alpha or c-erbB-2 expression was found between HCC with and without recurrence, or with and without extrahepatic metastasis. Expression of nm23 / tissue inhibitor of metalloproteinase (TIMP)-2 was positively associated with the prognosis of HCC patients (Log-rank, P<0.001). The alterative rates of above-mentioned genes and growth factors in small HCC were slightly lower than that in large ones, but no significant difference was shown except the p53 mutation.Conclusions The p53/CDKN2 mutation, overexpression of H-ras/EGFR, were associated with the invasiveness and recurrence of HCC. H-ras antisense gene might be of potential implication in the control of HCC recurrence and metastasis. Expression of nm23/TIMP-2 was closely related to the prognosis of HCC patients. Biological characteristics remained critical points to the prognosis even in small HCC.