Inhibitory effects of blockage of intermediate conductance Ca(2+)-activated K (+) channels on proliferation of hepatocellular carcinoma cells.

The roles of intermediate conductance Ca(2+)-activated K(+) channel (IKCa1) in the pathogenesis of hepatocellular carcinoma (HCC) were investigated. Immunohistochemistry and Western blotting were used to detect the expression of IKCa1 protein in 50 HCC and 20 para-carcinoma tissue samples. Real-time PCR was used to detect the transcription level of IKCa1 mRNA in 13 HCC and 11 para-carcinoma tissue samples. The MTT assay was used to measure the function of IKCa1 in human HCC cell line HepG2 in vitro. TRAM-34, a specific blocker of IKCa1, was used to intervene with the function of IKCa1. As compared with para-carcinoma tissue, an over-expression of IKCa1 protein was detected in HCC tissue samples (P<0.05). The mRNA expression level of IKCa1 in HCC tissues was 2.17 times higher than that in para-carcinoma tissues. The proliferation of HepG2 cells was suppressed by TRAM-34 (0.5, 1.0, 2.0 and 4.0 µmol/L) in vitro (P<0.05). Our results suggested that IKCa1 may play a role in the proliferation of human HCC, and IKCa1 blockers may represent a potential therapeutic strategy for HCC.

Effect of fragile histidine triad gene transduction on proliferation and apoptosis of human hepatocellular carcinoma cells.

AIM: To evaluate the inhibitory effects of human fragile histidine triad (FHIT) gene on cell proliferation and apoptosis in human hepatocellular carcinoma line Hep3B in vitro. METHODS: A recombinant pcDNA3.1 (+)/FHIT including the functional region of FHIT gene was constructed and transferred into human hepatocellular carcinoma cells in vitro. mRNA and protein expression of the FHIT gene in the transfected cells was detected by RT-PCR and Western blot, respectively. The effect of FHIT on proliferation was detected by MTT assay. Changes in cell cycle and apoptosis were assayed by flow cytometry. Five mice received subcutaneous transplantation of Hep3B-FHIT; 5 mice received subcutaneous transplantation of normal Hep3B and Hep3B-C as controls. The body weight of nude mice and tumor growth were measured. RESULTS: RT-PCR and Western blot analysis showed that the expression level of FHIT-mRNA and FHIT protein was higher in Hep3B cells after infection with pcDNA3.1 (+)/FHIT. The growth of Hep3B cells treated with pcDNA3.1 (+)/FHIT was significantly inhibited. The pcDNA3.1 (+)/FHIT-transfected Hep3B cells showed a significantly higher cell rate at G(0)-G(1) phase and increased apoptosis in comparison with controls (P < 0.05). The growth of transplanted tumor was inhibited markedly by FHIT. Tumors arising from the Hep3B-FHIT cells occurred much later than those arising from the Hep3B and Hep3B-C cells. The growth of Hep3B-FHIT cells was slow and the tumor volume was low. CONCLUSION: Transduction of FHIT gene inhibits the growth of human hepatocellular carcinoma cells and induces cell apoptosis in vivo and in vitro.

Clinicopathologic significance of BAG1 and TIMP3 expression in colon carcinoma.

AIM: To explore the expression of BAG1 and tissue inhibitor of metalloproteinase 3 (TIMP3) in colon carcinoma and their correlation and clinicopathologic significance. METHODS: SABC immunohistochemistry was used to detect the expression of BAG1 and TIMP3 in 80 colon carcinoma tissues and 20 normal colonic mucosa. RESULTS: Positive rate of BAG1 in colon carcinoma tissue (80%) was notably higher compared to normal colonic mucosa (10%) (P < 0.05). However, no significant difference was observed in positive rate of TIMP3 in colon carcinoma tissue (43.75%) as compared with normal colonic mucosa (60%) (P > 0.05). Expression of BAG1 and TIMP3 was strongly associated with colon carcinoma differentiation, Duke's staging, lymph node metastasis and survival rate (P < 0.05), but not associated with gender and age. Moreover, BAG1 expression was not correlated with TIMP3. CONCLUSION: Our results suggest that over-expression of BAG1 or attenuated expression of TIMP3 may play an important role in genesis and development of colon carcinoma. The protein expression levels of BAG1 and TIMP3 are related to the malignant degree, infiltration and metastasis of colon carcinoma. BAG1 and TIMP3 might be new biological parameters in predicting invasion and metastasis of colon carcinoma.

Melanoma differentiation-associated gene-7, MDA-7/IL-24, selectively induces growth suppression, apoptosis in human hepatocellular carcinoma cell line HepG2 by replication-incompetent adenovirus vector.

AIM: To investigate the effect of replication-incompetent adenovirus vector expressing MDA-7/IL-24 on tumor growth and apoptosis in human hepatocellular carcinoma (HCC) cell line HepG2 and normal liver cell line L02. METHODS: We constructed the recombinant replication-incompetent Ad.mda-7 virus vector and infected it into the human HCC cell line HepG2 and normal liver cell line L02. RT-PCR was performed to detect the mRNA expressing in cells. by ELISA was used to detect MDA-7/IL-24 protein expression in the culture supernatant. The effect of apoptosis induced by Ad.mda-7 was confirmed by Hoechst staining and flow cytometry assay with Annexin-V and PI staining. MTT assay was used to determine growth inhibition of HepG2 cells, and cell-cycle and hypodiploidy analyses were performed by flow cytometry. RESULTS: Recombinant replication-defective virus expressing MDA-7/IL-24 was constructed successfully. RT-PCR showed that the Ad.mda-7 could mediate the expression of the exogenous gene MDA-7/IL-24 into HepG2 and L02. The concentration of MDA-7/IL-24 protein in supernatant was 130 pg/mL and 110 pg/mL in Ad.mda-7-infected L02 and HepG2 cells, respectively. Ad.mda-7 infection obviously induced apoptosis (from 2.60%+/-0.72% to 33.6%+/-13.2%, P=0.00012) and growth suppression in HepG2 (inhibition ratio IR=68%) and an increase in the percentage of specific cancer cell types at the G2/M phase of the cell cycle (from 6.44% to 32.29%, P<0.01), but not in L02 cells. CONCLUSION: These results confirm selectively induction of apoptosis and growth suppression by the mda-7/IL-24 gene with replication-incompetent adenovirus vector in human hepatocellular carcinoma cell line HepG2.

Effects of BRAF(V600E) mutation on Na(+)/I(-) symporter expression in papillary thyroid carcinoma.

Radioiodine ablation (RIA) therapy is one of the most important treatments for papillary thyroid carcinoma (PTC), but some patients who received (131)I have radioiodine-refractory disease caused by the decreased expression of the Na(+)/I(-) symporter (NIS). BRAF(V600E) mutation is one possible risk factor that can disturb the NIS expression, but the roles are unclear in clinical practice. This research discussed the association of BRAF(V600E) mutation and NIS expression in PTC tissue and the clinical implications in RIA therapy. 134 PTC samples were collected between June 2013 and June 2014 from Tongji Hospital affiliated to Tongji Medical College, and their clinical characteristics were analyzed. RT-PCR was used to detect the BRAF(V600E) mutation from formalin-fixed paraffin-embedded samples, and immunohistochemistry was applied to detect the NIS expression. IPP software was used to calculate the relative expression quantity of NIS. We found that there was no significant correlation between the absorbance (A) values of NIS and clinicopathologic features in these cases, even thyroid stimulating hormone. BRAF(V600E) mutation showed inhibitory effect on the NIS expression without statistically significant difference in all PTC cases (ß=-0.0195, P=0.085), but in the subgroup without hashimoto's thyroiditis (HT), BRAF(V600E) mutation could significantly inhibit the NIS expression (ß=-0.0257, P=0.046). The results indicate that BRAF(V600E) mutation is correlated with a lower expression of NIS in PTCs without HT, suggesting the radioiodine-refractory effects during RIA therapy in these patients.

[PTEN induces anoikis through its phosphatase activity in hepatocellular carcinoma cells].

OBJECTIVE: To investigate the effect and mechanisms of tumor suppressor gene PTEN on the induction of anoikis of hepatocellular carcinoma SMMC-7721 cells. METHODS: SMMC-7721 cells were transfected with GFP plasmids containing wild-type PTEN or phosphatase inactivating mutant PTEN (C124A-PTEN) in vitro; The PTEN expression and the phosphorylation levels of focal adhesion kinase (FAK) and protein kinase B (PKB/Akt) were detected by Western blotting; Flow cytometry assay and laser scanning confocal microscopy were used to analyze apoptosis in adherent and non-adherent cells. RESULTS: Compared with the control, PTEN expression in the cells transfected with wild-type PTEN increased to 248%, while the phosphorylation level of FAK and Akt decreased 65.2% and 89.1%, respectively; and the anoikis percentage increased from 9.5% to 31.3%. In the cells transfected with C124A-PTEN, neither the phosphorylation of FAK and Akt nor the anoikis percentage had obviously changed, although the PTEN expression enhanced dramatically in comparison with the control. CONCLUSION: Through its phosphatase activity, tumor suppressor gene PTEN can suppress the phosphorylation of FAK and Akt, and induce anoikis in hepatocellular carcinoma cells.

Antitumor immunopreventive effect in mice induced by DNA vaccine encoding a fusion protein of alpha-fetoprotein and CTLA4.

AIM: To develop a tumor DNA vaccine encoding a fusion protein of murine AFP and CTLA4, and to study its ability to induce specific CTL response and its protective effect against AFP-producing tumor. METHODS: Murine alpha-fetoprotein (mAFP) gene was cloned from total RNA of Hepa1-6 cells by RT-PCR. A DNA vaccine was constructed by fusion murine alpha-fetoprotein gene and extramembrane domain of murine CTLA4 gene. The DNA vaccine was identified by restriction enzyme analysis, sequencing and expression. EL-4 (mAFP) was developed by stable transfection of EL-4 cells with pmAFP. The frequency of cells producing IFN-gamma in splenocytes harvested from the immunized mice was measured by ELISPOT. Mice immunized with DNA vaccine were inoculated with EL-4 (mAFP) cells in back to observe the protective effect of immunization on tumor. On the other hand, blood samples were collected from the immunized mice to check the functions of liver and kidney. RESULTS: 1.8 kb mAFP cDNA was cloned from total RNA of Hepa1-6 cells by RT-PCR. The DNA vaccine encoding a fusion protein of mAFP-CTLA4 was constructed and confirmed by restriction enzyme analysis, sequencing and expression. The expression of mAFP mRNA in EL-4 (mAFP) was confirmed by RT-PCR. The ELISPOT results showed that the number of IFN-gamma-producing cells in pmAFP-CTLA4 group was significantly higher than that in pmAFP, pcDNA3.1 and PBS group. The tumor volume in pmAFP-CTLA4 group was significantly smaller than that in pmAFP, pcDNA3.1 and PBS group, respectively. The hepatic and kidney functions in each group were not altered. CONCLUSION: AFP-CTLA4 DNA vaccine can stimulate potent specific CTL responses and has distinctive antitumor effect on AFP-producing tumor. The vaccine has no impact on the function of mouse liver and kidney.

Angiogenesis in rabbit hepatic tumor after transcatheter arterial embolization.

AIM: To investigate the effect of transcatheter arterial embolization (TAE) on angiogenesis of hepatic tumor. METHODS: Twenty New Zealand White rabbits were randomly divided into two groups of 10 each and VX2 carcinoma was implanted in the left medial lobes of the livers. Fourteen days later, a silicon catheter was inserted into the left hepatic artery of rabbit with VX2 hepatic tumor and infusion was performed via the hepatic artery using Lipiodol (the TAE group) or saline (the control group). Rabbits were sacrificed 7 d after treatment and tumor tissues were excised. Expression of vascular endothelial growth factor (VEGF) protein and microvessel density (MVD) of tumors were examined using immunohistochemistry. The staining intensity of VEGF was evaluated with a computer-assisted image-analyzer. Reverse transcription-polymerase chain reaction (RT-PCR) was used to detect the VEGF mRNA expression of tumors. RESULTS: MVD was higher in the TAE group compared with the control group (28.6+/-10.6 vs 16.3+/-6.9, P<0.01). Expression of VEGF protein was enhanced after TAE. The staining intensity of VEGF in the TAE group was 0.162+/-0.018, significantly higher than in the control group (0.142+/-0.01, P<0.01). At mRNA level, VEGF165 mRNA was significantly higher in the TAE group compared with the control group (2.58+/-0.42 vs 1.99+/-0.21, P<0.001). MVD was well correlated to VEGF expression in both the TAE group (r=0.69, P<0.05) and the control group (r=0.72, P<0.05). CONCLUSION: TAE promotes the development of neovascularization of residual tumors through up-regulation of VEGF expression, possibly due to hypoxic insult.

Specific cellular immunity and antitumor responses in C57BL/6 mice induced by DNA vaccine encoding murine AFP.

BACKGROUND: The inoculation of plasmid DNA encoding tumor-associated antigens is a novel and powerful strategy for antitumor vaccination. This study was designed to construct the DNA vaccine of mouse AFP and to observe the specific cellular immunologic responses and the antitumor responses in mice induced by this vaccine. METHODS: The murine AFP gene was amplified by RT-PCR from total RNA extracted from Hepa1-6 cells and cloned into the vector pcDNA3.1 to construct pmAFP. The DNA vaccine was identified by restriction enzyme analysis, sequencing and expression. EL-4 (mAFP) was developed by stable transfection of EL-4 cells with pmAFP. The frequency of cells producing IFN-gamma in splenocytes harvested from the mice immunized with the DNA vaccine by intramuscular injection was measured by enzyme linked immunospot (ELISPOT). The mice immunized with the DNA vaccine were inoculated with EL-4 (mAFP) cells in back to observe the inhibitory effect of the immunization on tumor. On the other hand, blood samples were collected from the immunized mice to check the functions of the liver and kidney. RESULTS: The murine AFP gene was successfully cloned by RT-PCR. Results from restriction enzyme analysis, sequencing and expression showed that the DNA vaccine was successfully constructed. The expression of mAFP mRNA in EL-4 (mAFP) was confirmed by RT-PCR. The results of ELISPOT showed that the number of IFN-gamma- producing cells of the pmAFP vaccine group was significantly higher than that of other groups (P<0.01). The tumor volume in the pmAFP vaccine group (1042.42+/-123.71 mm(3)) was significantly smaller than that in other groups (P<0.01). The function of mouse liver and kidney in each group was unchanged. CONCLUSION: The successfully constructed DNA vaccine of AFP can induce specific cellular immunologic responses and significant antitumor responses in mouse and has no impact on the function of mouse liver and kidney.

[PTEN induces apoptosis and up-regulates p53 expression in HepG2 cells].

OBJECTIVE: To investigate the effects of tumor suppressor gene PTEN on apoptosis and protein expression of p53 in HepG2 cells, as well as to explore its mechanisms. METHODS: HepG2 cells were transfected with GFP plasmids containing wild-type PTEN or G129E-PTEN and C124A-PTEN in vitro. Both the expression of wild-type p53 and the phosphorylation of protein kinase B (PKB/Akt) and focal adhesion kinase (FAK) were detected by Western blotting. Flow cytometry and confocal microscopy were used to analyze apoptosis of the transfected cells. RESULTS: Compared with the control, the expression of phosphorylated FAK and phosphoylated Akt were down-regulated in HepG2 cells transfected with wild-type PTEN (-65%, -93%) and G129E-PTEN (-65%, -35%), whereas the apoptosis percentage increased to (19.8+/-1.2)% and (9.2+/-0.6)%, and p53 expression was up-regulated by 120% and 50%, respectively. However, in the cells transfected with C124A-PTEN, neither the phosphorylation of FAK and Akt nor the apoptosis percentage and p53 expression had changed. CONCLUSION: PTEN can dephosphrylate FAK through its protein phosphatase activity, and suppress phosphorylation of Akt mainly through its lipid phosphatase activity. Consequently, it can induce apoptosis of HepG2 cells and up-regulate p53 expression.

[Meta-analysis on curative effects of surgical procedures for intrahepatic bile duct lithiasis].

OBJECTIVE: To compare curative effects of various surgical procedures of bile duct stones. METHODS: Two thousand nine hundred and fifty-five patients with intrahepatic bile duct lithiasis who had undergone various surgical procedures were analysed with Meta-analysis. Some of these cases were reported in Chinese Medical Journals from January 1990 to March 2001 and others were from Tongji Hospital. RESULTS: There was a significant difference between curative effects of non-hepatectomy and that of hepatectomy (chi(2) = 62.945, P < 0.01), and the outcomes of hepatectomy were much better than those of non-hepatectomy with OR(S) equalled to 0.303 (0.222 - 0.413). There was not a significant difference between curative effect of interposed jejunum and that of hepatectomy (95% CI of RR from 0.98 to 1.04). All the other operation, effects were worse than hepatectomy (upper limit of 95% CI of RR < 1). CONCLUSIONS: Hepatectomy is the most ideal surgery for intrahepatic bile duct stones and operation methods should be diversified since good effect could also be obtained when other operations are performed on suitable cases.

[Effect of protecting parathyroid in situ in the operation of total thyroidectomy].

OBJECTIVE: To evaluate the effect of protecting parathyroid glands in situ in the operation of total thyroidectomy by detecting parathyroid hormone after the operation. METHODS: In the surgical team, 1019 consecutive patients with thyroid diseases were treated with total thyroidectomy. During the operation, parathyroid glands were protected in situ with correctly identifying the parathyroid glands, precisely dissecting its envelope and protecting its blood supply. Serum calcium level and parathyroid hormone were measured before and 24 hours after operation. The patients who had symptomatic hypocalcemia or hypoparathyroidism were given supportive treatment and followed-up. RESULTS: At least one of the parathyroid glands was preserved and remained in situ in all cases. Eighty-nine cases (8.7%) had decreased parathyroid hormone levels and 42 cases (4.1%) had complicated symptomatic hypocalcemia. The symptoms of hypocalcemia in all these cases could be controlled by supportive treatment, and serum calcium level and parathyroid hormone had all recovered 1 - 6 months later. If 3 and 4 parathyroid were conserved in situ, the postoperative complication rate was significantly lower than those with 1 and 2 parathyroid conserved (decreased PTH 69/999 vs 20/20, symptoms of hypocalcemia 25/999 vs 17/20, all P < 0.01). CONCLUSION: The techniques to protect parathyroid glands in situ are effective measure to prevent the postoperative hypoparathyroidism in total thyroidectomy.

[Conservative therapy in the treatment of cervical chylous leakage].

OBJECTIVE: To explore and evaluate the combined conservative managements in the treatment of cervical chylous leakage. METHODS: Thirty nine cases of cervical chylous leakage from June 1992 to June 2008 were retrospectively analyzed in this hospital. All of the 39 cases were cured by treating with conservative individualized therapy, including the applying of diet with high calorie, high protein and low fat and fatty food should only contains medium-chain triglycerides, total parenteral nutrition, keep the balance of hydrogen and electrolyte and correct hypoproteinemia, local pressure dressing, high persistent vacuum drainage (-50 approximately -80 kPa) and/or somatostatin analogue. RESULTS: All the cases of chylous leakage happened 2nd to 5th days after the operation. Among the 39 cases, 7 were high flow (drainage>or=500 ml/d) chylous leakage, the amount of drainage reached as high as 1440 ml per day. The time of chylous leakage closure was 3 approximately 12 days, and the mean time was 7 days. No one experienced re-operation, wound hydrops or wound infection. CONCLUSIONS: The conservative individualized therapy may play a key role in the treatment of cervical chylous leakage.

[Optimized expression of a single-chain Fv antibody against human asialoglycoprotein receptor and determination of its affinity constant].

AIM: To express and purify a single chain Fv antibody (scFv) C1 against human hepatic asialoglycoprotein receptor (ASGPR) and to determine affinity constant of the purified scFv C1. METHODS: The specific anti-ASGPR phage clone C1 was transfected into E. coli HB2151. The single colony was chosen to be inoculated into 2 x TY medium and shaken (250 r/min) overnight at 37 degrees C. After 1 in 100 dilution in 2 x TY medium and induced for secreted expression, scFv C1 was induced at different concentrations (0.25, 0.5 and 1.0 mmol/L IPTG) overnight at 37 degrees C, 25 degrees C and 20 degrees C, respectively. The supernatant was precipitated with saturated ammonium sulfate and its sediment was analyzed by SDS-PAGE. In addition, the sediment was resuspended in 30 mL PBS and dialyzed against PBS overnight at 4 degrees C. The expressed scFv C1 was purified by Ni(2+) chelating HiTrap HP column and the purity of the purified scFv C1 was identified by SDS-PAGE. Then affinity constant of scFv C1 was determined by noncompetitive enzyme immunoassay. RESULTS: After induced with 0.5 mmol/L IPTG overnight at 25 degrees C, the amount of expressed scFv C1 increased greatly and its relative molecular mass was about 28,000, and it existed in culture supernant in soluble form. The purity of scFv C1 by nickel-agarose column was above 95% and its yield was about 0.8 mg/L. The affinity constant of the purified scFv C1 was confirmed to be (2.31+/-0.36)x10(-7) mol/L. CONCLUSION: The E. coli HB2151 infected with phage C1 clones may express soluble scFv C1 with low affinity, which has potential applications to gene therapy of hepatocellular carcinoma.