Efficacy and Safety of Multiband Mucosectomy Versus Cap-assisted Endoscopic Resection For Early Esophageal Cancer and Precancerous Lesions: A Systematic Review and Meta-Analysis.

BACKGROUND: The effectiveness of multiband mucosectomy (MBM) for early esophageal cancer and precancerous lesions is still in uncertainty. We aimed to evaluate the efficacy and safety of this procedure and to compare it with cap-assisted endoscopic resection (EMR-cap). METHODS: A systematic search of both English and Chinese databases was performed from inception to April 30, 2019. Complete resection rate, local recurrence rate, and procedure time were considered the primary outcome measures. Prevalence of complications was considered the secondary outcome measure. All data analyses were performed using Review Manager Software. RESULTS: Two randomized controlled trials (RCTs) and 3 non-RCTs were included in the final meta-analysis. When compared with the EMR-cap technique, MBM had a similar complete resection rate [odds ratio (OR)=2.09, 95% confidence interval (CI): 0.78-5.60, P=0.14], a similar local recurrence rate (OR=0.50, 95% CI: 0.09-2.67, P=0.42), a shorter resection time (mean difference: -9.08, 95% CI: -13.86 to -4.30, P=0.0002), a shorter procedure time (mean difference: -13.36, 95% CI: -17.85 to -8.86, P<0.00001), a lower bleeding rate (OR=0.45, 95% CI: 0.24-0.83, P=0.01), a similar perforation rate (OR=0.55, 95% CI: 0.15-2.06, P=0.37), and a similar stricture rate (OR=0.77, 95% CI: 0.10-5.84, P=0.80). The results of non-RCTs were consistent with those of RCTs. CONCLUSIONS: MBM is similar to EMR-cap in terms of efficacy and safety for endoscopic resection of early cancer and precancerous lesions of the esophagus. However, MBM is less time-consuming.

FOXM1 promotes proliferation in human hepatocellular carcinoma cells by transcriptional activation of CCNB1.

The transcription factor Forkhead box protein M1 (FOXM1) plays critical roles in cancer development and progression, including human hepatocellular carcinoma (HCC). However, the regulatory role and underlying mechanisms of FOXM1 is still limited. Here, we found that the high level expression of FOXM1 and CCNB1 is closely associated with poor prognosis in HCC patients. And FOXM1 and CCNB1 were overexpressed concomitantly in liver tumor tissues. Knockdown of FOXM1 significantly inhibited the expression levels of CCNB1 in HCC cell lines at both the mRNA and protein levels. Mechanistic studies revealed that FOXM1 binds directly to the promoter region of CCNB1 and regulates the expression levels of the CCNB1 gene in the transcriptional level. Furthermore, the loss of functional and rescue experiments showed that CCNB1 is essential for FOXM1-driven proliferation in HCC cells. In the present study, our results partially explained the dysregulated expression of FOXM1 play an important role in proliferation of human hepatocellular carcinoma cells via transcriptional activation of CCNB1 expression. And it also highlights a FOXM1/CCNB1 axis could be a potential target for the treatment of HCCs.

MicroRNA-7/NF-κB signaling regulatory feedback circuit regulates gastric carcinogenesis.

MicroRNAs play essential roles in gene expression regulation during carcinogenesis. Here, we investigated the role of miR-7 and the mechanism by which it is dysregulated in gastric cancer (GC). We used genome-wide screenings and identified RELA and FOS as novel targets of miR-7. Overexpression of miR-7 repressed RELA and FOS expression and prevented GC cell proliferation and tumorigenesis. These effects were clinically relevant, as low miR-7 expression was correlated with high RELA and FOS expression and poor survival in GC patients. Intriguingly, we found that miR-7 indirectly regulated RELA activation by targeting the IκB kinase IKKε. Furthermore, IKKε and RELA can repress miR-7 transcription, which forms a feedback circuit between miR-7 and nuclear factor κB (NF-κB) signaling. Additionally, we demonstrate that down-regulation of miR-7 may occur as a result of the aberrant activation of NF-κB signaling by Helicobacter pylori infection. These findings suggest that miR-7 may serve as an important regulator in GC development and progression.

SUMO-specific protease 6 promotes gastric cancer cell growth via deSUMOylation of FoxM1.

SUMOylation is a post-translational modification exerted various effects on the target proteins. SUMOylation is a highly dynamic and reversible process, which has been shown to play an important role in tumorigenesis. However, the roles of sentrin/SUMO-specific proteases (SENPs), which mediate the reverse process of SUMOylation, in tumorigenesis remains largely unexplored. Here, we uncover a critical role of SENP6 in promoting gastric cancer cells growth via regulating the deSUMOylation of a transcription factor forkhead box protein M1 (FoxM1). We demonstrated that the mRNA and protein levels were elevated in gastric cancer tissues. Overexpression of SENP6 promoted, while RNA interference depletion of endogenous SENP6 inhibited gastric cancer cells growth and the ability of colony formation. By using biochemical assays, we identified FoxM1 as a novel substrate of SENP6 in gastric cancer cells. Thus, our data suggest that SENP6, which is highly expressed in gastric cancer cells, regulates the transcriptional activity and stability of FoxM1 through deSUMOylation.

Purification of a Pd20-TNFα fusion protein that prevents liver metastasis of gastric cancer.

The specific binding peptide pd20 of gastric cancer cells with a high potential for liver metastasis was fused with human tumour necrosis factor (TNF) α, and a prokaryotic expression vector was established to express the pd20-TNFα fusion protein. After purification and identification, the preventive effects of the fusion protein on liver metastasis of gastric cancer were observed in mice. The whole gene synthesis method was used for pd20-TNFα fusion gene preparation, and a pd20-TNFα prokaryotic expression vector was constructed. The vector was induced and expressed in Escherichia coli BL21. The expression products were analysed and verified by SDS-PAGE electrophoresis and Western blot analysis. The Ni-NTA column method was used to purify the fusion protein, and the L929 cytotoxicity method was used to detect biological activity. Flow cytometry apoptosis experiments and invasion assays were performed to observe the effects of the fusion protein on apoptosis and metastasis of gastric cancer cells with high potential for liver metastasis. Thirty nude mice with liver metastasis of gastric cancer were established and then randomly divided into three groups of ten mice each. The Pd20-TNFα recombinant protein (1.2 × 10(6) U/kg day) or standard TNFα (1.2 × 10(6) U/kg day) saline was administered via tail vein injection for 7 consecutive days. The pathological changes in various organs of nude mice were observed 4 weeks later. The size of the gastric cancer, the incidence of liver metastasis and the number of liver metastases were measured and calculated. We successfully constructed a Pd20-TNFα recombinant plasmid and prepared the fusion protein. Detection of the pd20-TNFα protein by immunofluorescence showed a very strong expression in liver tissue, suggesting a targeting of the fusion protein to the liver. The L929 cytotoxicity assays showed that the pd20-TNFα fusion purified protein had a significant lethal effect on L929 cells, with a killing activity of up to 7.6 × 10(6) IU/ml. The apoptosis experiments showed that as the concentration of the fusion protein increased, the early gastric cancer cell apoptosis also increased, with the early apoptosis rate increasing from 5.99 % to 9.04 %. Cell invasion experiments showed that the purified pd20-TNFα fusion protein significantly inhibited the in vitro invasion of XGC9811-L cells, with the penetrating cells being significantly decreased compared with the control group per unit time (P < 0.01). Vector experiments showed that the pd20-TNFα recombinant protein group had significantly reduced cancer lesions and liver metastasis in nude mice compared with the control group. We successfully purified a pd20-TNFα fusion protein and confirmed that it had significant biological activity promoting early gastric cancer cell apoptosis, thereby inhibiting gastric cancer cell invasion.

[The expression of hepatitis B virus X protein and cyclooxygenase-2 in hepatitis B virus-related hepatocellular carcinoma: correlation with microangiogenesis and metastasis, and what is the possible mechanism].

OBJECTIVE: To investigate the expression of HBx and COX-2 in hepatitis B virus-related hepatocellular carcinoma, and Its correlation with microangiogenesis and metastasis, and possible mechanism. METHODS: Immunohistochemistry was used to detect the expression of hepatitis B virus X, cyclooxygenase-2 and CD34 in hepatitis B virus related hepatic carcinoma and 22 non-HBV related hepatic carcinoma tissues. The expression of hepatitis B virus x protein and cyclooxygenase-2 in hepatitis B virus-related hepatocellular carcinoma correlated with microangiogenesis and metastasis was tested by Spearman correlation analysis. The expression of COX-2 in HepG2-X was detected by Western blot and RT-PCR. PGE2 was detected by ELISA in clear supernatant liquid of HepG2-X. Trypan blue exclusion was performed to examine the inhibitory effects of COX-2 selective inhibitor (celecoxib). RESULTS: In Hepatitis B carcinoma tissue, HBx and COX-2 were expressed at high level. The positive rate of COX-2 expression was 88.87% (55/62) in HBx positive expression group, which was significantly higher than that of the positive expression 31.82% (7/22, x2=27.188, P<0.01) in HBx negative expression group and 40.91% (9/22, x2=20.453, P<0.01) in non-HBV related hepatic carcinoma tissues, but it had no statistical difference (x2=0.393, P=0.531) between the HBx negative expression group and non-HBV related hepatic carcinoma tissue group. The expressions of HBx and COX-2 in metastasis group were higher than that in non-metastasis group (P<0.01), MVD in HBx or COX-2 positive expression group was significantly higher than that in negative expression group and non-HBV related hepatic carcinoma tissues (P is less than 0.01). MVD with metastasis was higher than that without metastasis (P<0.01) and MVD with portal vein invasion was higher than that without invasion (P<0.05). Spearman correlation analysis showed that the expression of COX-2 was significantly correlated with the expression of HBx (Rs=0.568, P<0.01). Celecoxib suppressed the growth of both cells in a dose-dependent manner. HepG2-X was significantly susceptible to celecoxib as compared to the HepG2-PC cells. COX-2 protein and mRNA were upregulated in HepG2-X cells than in HepG2-PC. Moreover, PGE2 was upregulated in clear supernatant liquid of HepG2-X than in HepG2-PC. CONCLUSION: The expressions of HBx and COX-2 were higher in HBV-related hepatocellular carcinoma. COX-2 was significantly correlated with HBx in HCC and it could be a key factor involved in HBx contributed hepatocellular carcinoma's microangiogenesis and metastasis. The possible mechanism of the dual effects might be through HBx, COX-2 and PGE2 pathways in infiltration involved metastasis and microangiogenesis involved metastasis.

[Expression of URG4 in hepatocellular carcinoma and its correlation with HBx].

AIM: To investigate the expression of URG4 in HCC (Hepatocellular carcinoma) and its correlation with HBx. METHODS: Immunohistochemistry was performed to examine the expression of URG4 and HBx in HCC tissues, adjacent nontumor tissues and normal lives tissues. RESULTS: The expression rate of URG4 in HCC tissues and adjacent nontumor tissues were 48% and 54% respectively, while there was only 22.2% weak URG4 expression in normal tissues. Correlation coefficient between expression of HBx and URG4 was 0.38 in HCC tissues (P<0.05) and 0.45 in adjacent nontumor tissues (P<0.05). CONCLUSION: Expression of URG4 in HCC tissues, adjacent nontumor tissues, and HCC cell lines was much higher than that of normal tissues and cells. Expression of URG4 in HCC is closely related with HBx.

[Expression and significance of glypican-3 in colorectal cancer].

OBJECTIVE: To investigate the expression and significance of Glypican-3 in colorectal cancer. METHODS: Immunohistochemistry was used to detect the expression of Glypican-3 in 200 specimens of colorectal cancer and adjacent non-cancerous tissues resected during operation. RESULTS: Glypican-3 immunoreactivity was recognized in both the cytoplasm and cellular membrane. The Glypican-3 positive expression rate in the tumor samples was 66.0% (132/200), significantly higher than that in the adjacent nontumor tissues (24%, 48/200, P = 0.019). The Glypican-3 expression rate was significantly correlated with the carcinoma invasion (P = 0.023) and lymph node metastasis (P = 0.015), but not associated with gender, age, tumor size, and differentiation grade (all P > 0.05). CONCLUSION: Over-expression of Glypican-3 may play an important role in the genesis and development of colorectal cancer, and may be used as a new biological parameter in predicting invasion and metastasis of colorectal carcinoma.

[The potential role of Id1 in COX-2 mediated angiogenesis in gastric cancer].

OBJECTIVE: To investigate the potential role of inhibitor of DNA binding/differentiation 1 (Id1) in cyclooxygenase-2 (COX-2) mediated angiogenesis in gastric cancer. METHODS: Two human gastric cancer sub-cell lines (SGC7901/COX-2 and SGC7901/COX-2RNAi) highly expressing COX-2 and COX-2 RNAi respectively were established. Western blotting and RT-PCR were performed to detect the protein and mRNA expression levels of Id1 in these transfectants. ELISA was performed to detect the levels of VEGF protein in the supernatants of these cells. Humane umbilical vein endothelial cells of the line HU-LT were cultured in condition medium, supernatant of SGC7901/COX2 cells transfected with COX-2 sense strand, COX-2 SiRNA and Id1. MTT assay was used to examine the proliferation ability of these cells. Suspensions of SGC7901/COX-2 and SGC7901/COX-2RNAi cells were injected subcutaneously to nude mice respectively. Eight weeks later the mice were killed and the tumors were taken out to undergo immunohistochemistry and detection of mcrovessel density (MVD). RESULTS: Western blotting and RT-PCR showed that the expression levels of COX-2 protein and mRNA, as well as those of Id1 in the SGC7901/COX-2 cells were high, and the expression level of Id1 was down-regulated in the SGC7901/COX-2RNAi cells transfected with Id1 RNAi. The VEGF level of the SGC7901/COX-2 cells was 2060 +/- 42, significantly higher than that of the control SGC7901/PC cells (1248 +/- 28, P = 0.000) and VEGF level of the supernatant of then SGC7901/COX-2 RNAi cells was 1024 +/- 20, significantly lower than that of the SGC7901/COX-2/PC cells (2033 +/- 27, P = 0.000). The proliferation rate of the HU-LT cells cultured in SGC7901/COX-2 condition medium was higher than that of the HU-LT cells cultured in SGC7901/COX-2RNAi condition medium. The increase of VEGF in the SGC7901/COX-2 and the effect of contribution to the proliferation of HU-LT were both abrogated when Id1 was knocked out in the SGC7901/COX-2. The tumor weight of the COX-2 RNAi group was (353 +/- 12) mg, significantly lower than that of the SGC7901/COX-2 group [(1020 +/- 91) mg, P = 0.038]. The MVD of the tumor of the COX-2 RNAi group was 8.8 +/- 1.6, significantly lower than that of the SGC7901/COX-2 group (20 +/- 1.7, P = 0.001). CONCLUSION: COX-2 can stimulate VEGF and enhance the proliferation of endothelial cells by upregulating Id1, and blocking this pathway may be helpful to the tumor therapeutics, so COX-2 and Id1 can be exploited as therapeutic targets of gastric cancer.

[Expressions of hepatitis B virus x protein and hypoxia-inducible factor-1alpha in hepatocellular carcinoma and their possible relationships].

OBJECTIVE: To investigate the expressions of hepatitis B virus x protein (HBx) and hypoxia-inducible factor-1alpha (HIF-1alpha) in hepatocellular carcinoma (HCC) tissues and HepG2 cells under normoxic and hypoxic conditions. METHODS: Immunohistochemistry was used to detect the expressions of HBx and HIF-1alpha in 78 hepatic carcinoma tissues, and their possible relationships were analyzed using SPSS 10.0 statistical software. Immunofluorescence and Western blot were used to investigate the expression of HIF-1alpha in HepG2 and HepG2-X cells under normoxic and hypoxic conditions. Flow cytometric analysis was used to measure reactive oxygen species (ROS) in HepG2 and HepG2-Xd cells under normoxic and hypoxic conditions. RESULTS: The positive rate of HBx in the hepatocellular carcinoma tissues was 74.36% (58/78), while the positive rate of HIF-1alpha was 69.23% (54/78). Under normoxic condition, HIF-1alpha was mainly localized in the cytoplasm and partially translocated into the nuclei of most HepG2-X cells, while under hypoxic condition the expression of HIF-1alpha was positive in the cytoplasm and nuclei of HepG2 and HepG2-X cells. Under normoxic condition the expression of HIF-1alpha was negative in the HepG2 cells while it was positive in HepG2-X cells, but HIF-1alpha was upregulated time-dependently in both HepG2 and HepG2-X cells under hypoxia condition. Furthermore, HepG2-X cells had a higher level of ROS than HepG2 cells under normoxic condition, while under hypoxic condition, the levels of ROS in HepG2 and HepG2-X cells were not significantly different, but the levels of ROS in HepG2 and HepG2-X cells under hypoxia condition were higher than those under normoxia condition. CONCLUSION: HBx and HIF-1alpha were widely expressed in HCC tissues and there is a positive relationship between them. HIF-1alpha can be upregulated by HBx in HepG2 cells under normoxic and hypoxia conditions. Regulation of HIF-1alpha by HBx in HCC might be via the ROS pathway.

[Construction of eukaryotic expression vector of siRNA specific for MAD2 and its effect on the growth of gastric cell line SGC7901].

AIM: To construct the RNA interference eukaryotic expression vector specific for human MAD2 gene and to observe its effect on the growth of gastric cancer cell line SGC7901. METHODS: The expression vectors of pSilencer3.1/MAD2-siRNA1 and pSilencer3.1/MAD2-siRNA2 were constructed by gene recombination and then were stably transfected into the gastric carcinoma cell line SGC7901 by liposome mediation. The expression of MAD2 on the levels of protein and mRNA was detected by Western blot and RT-PCR, and the monoclone with the highest inhibition efficiency was selected. The growth of the transfected cells was assessed by MTT. And the cells treated with 1.0 mg/L vincristine (VCR) for 24 h were analyzed by FCM for cell cycle. RESULTS: Sequence-specific siRNAs targeting MAD2 significantly down regulated the expression of MAD2 in SGC7901 cells. In MAD2-siRNA transfected cells, the rate of cell growth increased markedly and cell cycle couldn't be arrested in M phase induced by VCR, while the cells transfected with the mock vector could. CONCLUSION: Down regulation of MAD2 expression of SGC7901 bv sequence-specific siRNA could accelerate the cell growth and impair the mitosis arrest of SGC7901 induced by VCR.