MicroRNA-613 induces the sensitivity of gastric cancer cells to cisplatin through targeting SOX9 expression.

Increasing evidences have suggested that deregulated miRNAs may involve in drug chemoresistance in a lot of human cancers. However, the role of miR-613 in drug chemoresistance of GC cell is still unknown. The expression of miR-613 and Sex-determining region Y (SRY)-box 9 (SOX9) in GC tissues and cell lines was detected by using qRT-PCR. Cell migration and viability were measured by the wound healing assay and CCK-8 assays. Western blot and dual-luciferase reporter were done to identify the target gene of miR-613. We showed that miR-613 expression was downregulated in GC tissues and cell lines. Ectopic expression of miR-613 increased the sensitivity of GC cells to cisplatin. Overexpression of miR-613 suppressed GC cell proliferation, cycle and migration. In addition, we identified SOX9 was a direct target gene of miR-613 in GC cell. We showed that SOX9 expression was upregulated in gastric cancer samples. Moreover, the expression of SOX9 was negatively correlated with miR-613 expression in GC tissues. Furthermore, elevated expression of miR-613 increased the sensitivity of GC cells to cisplatin and suppressed GC cell proliferation and migration by targeting SOX9. These data suggested that miR-613 might function as a chemoresistant suppressor in GC.

hsa_circ_0081143 promotes cisplatin resistance in gastric cancer by targeting miR-646/CDK6 pathway.

BACKGROUND: Increasing studies indicated that circRNAs play critical roles in tumor progression. However, the roles and underlying mechanisms of circRNAs in gastric cancer (GC) remain largely unclear. METHODS: Microarray assay was used to screen the abnormally expressed circRNAs in GC. Cell viability assay, transwell assay and in vivo assay were performed to assess the effects of hsa_circ_0081143 on GC cells. Next, interaction between hsa_circ_0081143 and miR-646 was detected by luciferase reporter assay and RNA pull-down assay. RESULTS: High throughput microarray assay showed that hsa_circ_0081143 was upregulated in GC tissues, which was further confirmed by qRT-PCR. Correlation analysis showed that high hsa_circ_0081143 expression was associated with the advanced TNM stage, lymphnode metastases, and poor overall survival of GC patients. Hsa_circ_0081143 inhibition decreased GC cells viability, invasion ability and induced the sensitivity of GC cells to cisplatin (DDP) in vitro. Mechanistically, we showed that hsa_circ_0081143 could act as an endogenous sponge by directly binding to miR-646 and downregulation of miR-646 efficiently reversed the inhibition of CDK6 induced by hsa_circ_008114 knockdown. Additionally, hsa_circ_0081143 silencing suppressed the tumorigenesis and remarkably enhance DDP inhibitory effects of GC cells in vivo. CONCLUSIONS: Our study indicated a novel regulatory loop that hsa_circ_0081143/miR-646/CDK6 axis in GC progression. These data suggested that hsa_circ_0081143 might act as a potential novel therapeutic strategy for GC treatment.

Long noncoding RNA ABHD11-AS1 promote cells proliferation and invasion of colorectal cancer via regulating the miR-1254-WNT11 pathway.

The purpose of our study was to investigate the effects of the long noncoding RNA (lncRNA) ABHD11-AS1 on colorectal cancer (CRC) progression and further explore its possible underlying mechanisms. In the study, we found that ABHD11-AS1 was highly expressed in CRC tissues and cell lines. High ABHD11-AS1 expression was correlated with poor overall survival of patients with CRC. ABHD11-AS1 knockdown reduced CRC cell proliferation, in vitro invasion, and in vivo tumor growth. Investigation of the underlying mechanism showed that ABHD11-AS1 could act as a molecular sponge of miR-1254, and WNT11 was a downstream target of miR-1254 in CRC. Moreover, there was a negative association between ABHD11-AS1 expression (or WNT11) and miR-1254 in CRC tissues. The rescue assays showed that WNT11 overexpression partially rescued the effects of ABHD11-AS1 inhibition on CRC progression. Thus, we demonstrated that ABHD11-AS1 promotes CRC progression through the miR-1254-WNT11 pathway, which provides a new insight into the therapeutic strategies for CRC.

Upregulation of miR-199a/b contributes to cisplatin resistance via Wnt/ß-catenin-ABCG2 signaling pathway in ALDHA1+ colorectal cancer stem cells.

Cisplatin resistance in colorectal cancer largely results from the colorectal cancer stem cells which could be targeted to improve the efficacy of chemotherapy. MicroRNAs are possible modulators of cancer stem cell characteristics and maybe involved in the retention of cancer stem cell chemoresistance. The aim of this study was to investigate the biological function of miR-199a/b on cisplatin resistance in colorectal cancer stem cells and its related mechanisms. Here, ALDHA1+ cells from primary colorectal cancer tissues behaved similar to cancer stem cells and were chemoresistant to cisplatin. The presence of a variable fraction of ALDHA1 was detected in 9 out of 10 colorectal cancer specimens. Significantly, increased miR-199a/b expression was detected in ALDHA1+ colorectal cancer stem cells, accompanied by a downregulation of Gsk3ß and an overexpression of ß-catenin and ABCG2. In patient cohort, enhanced miR-199a/b expression in colorectal cancer tissues was associated with cisplatin response and poor patient survival. In addition, 80% of colorectal cancer samples showed lower level of Gsk3ß than their adjacent normal counterparts. Furthermore, Gsk3ß was the direct target of miR-199a/b. MiR-199a/b regulated Wnt/ß-catenin pathway by targeting Gsk3ß in ALDHA1+ colorectal cancer stem cells. By blocking Wnt/ß-catenin pathway, we implied that ABCG2 lies downstream of Wnt/ß-catenin pathway. ABCG2 was further demonstrated to contribute cisplatin resistance in ALDHA1+ colorectal cancer stem cells and can be regulated by miR-199a/b. Thus, our data suggested that upregulation of miR-199a/b in ALDHA1+ colorectal cancer stem cells contributed to cisplatin resistance via Wnt/ß-catenin-ABCG2 signaling, which sheds new light on understanding the mechanism of cisplatin resistance in colorectal cancer stem cells and facilitates the development of potential therapeutics against colorectal cancer.

Basic Transcription Factor 3 Is Required for Proliferation and Epithelial-Mesenchymal Transition via Regulation of FOXM1 and JAK2/STAT3 Signaling in Gastric Cancer.

Gastric cancer (GC) is the most common epithelial malignancy worldwide. Basic transcription factor 3 (BTF3) plays a crucial role in the regulation of various biological processes. We designed experiments to investigate the molecular mechanism underlying the role of BTF3 in GC cell proliferation and metastasis. We confirmed that BTF3 expression was decreased in GC tissues and several GC cell lines. Lentivirus-mediated downregulation of BTF3 reduced cell proliferation, induced S and G2/M cell cycle arrest, and increased apoptosis. Knockdown of BTF3 significantly reduced the expression of Forkhead box M1 (FOXM1). Upregulation of FOXM1 significantly inhibited the decrease in cell proliferation due to BTF3 silencing, S and G2/M cell cycle arrest, and increase in apoptosis. Knockdown of BTF3 decreased Ki-67 and PCNA expression, whereas it increased p27 expression, which was inhibited by upregulation of FOXM1. Knockdown of BTF3 significantly decreased the ability to invade and migrate. Moreover, knockdown of BTF3 increased E-cadherin expression, whereas it decreased N-cadherin and ZEB2 expression, indicating a decrease in epithelial-mesenchymal transition (EMT). Phosphorylation of Janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) was significantly inhibited by knockdown of BTF3. IL-6-stimulated phosphorylation of STAT3 and JAK2 markedly suppressed inhibition of EMT due to BTF3 silencing. Silencing of BTF3 decreased tumor volume and weight and reduced peritoneal nodules in implanted tumors. Our findings provide a novel understanding of the mechanism of GC and highlight the important role of BTF3/FOXM1 in tumor growth and BTF3/JAK2/STAT3 in EMT and metastasis.

In vitro-activated tumor-specific T lymphocytes prolong the survival of patients with advanced gastric cancer: a retrospective cohort study.

BACKGROUND: Conventional tumor managements have limited survival benefits and cause severely impaired immune function in patients with advanced gastric cancer (GC) whereas immunotherapies could restore antitumor immunity. This prospective cohort study was aimed at investigating the efficacy of in vitro-activated tumor-specific T lymphocytes combined with chemotherapy on the survival of patients with advanced GC. PATIENTS AND METHODS: Two hundred and seventy-four postoperative patients were enrolled in this study to receive either activated T lymphocytes immunotherapy combining chemotherapy (71 patients) or only receive postoperative chemotherapy (203 patients). Overall survival was analyzed by the Kaplan-Meier with log-rank test and Cox's regression methods. RESULTS: The immunotherapy prolonged 9.8-month median survival for advanced gastric cancer (29.70 vs 19.70 months, P=0.036). Furthermore, immunotherapy significantly benefited the survival of patients who underwent radical, palliative resection, and stage III malignancy. No serious adverse effect was observed in the immunotherapy group. CONCLUSION: In vitro-activated tumor-specific T lymphocytes prolonged survival in patients with advanced GC.

Let-7a mimic attenuates CCL18 induced breast cancer cell metastasis through Lin 28 pathway.

BACKGROUND: MicroRNAs are believed to influence breast cancer cell tumorgenicity by interacting with the production of tumor associated macrophages. At this stage, this hypothesis lacks sufficient empirical evidence. Our study is an investigation of the effects of let-7a on the function of human breast cancer cell lines that had undergone chemokine ligand 18 (CCL18) stimulation. METHODS: Two breast cancer cell lines MDA-MB-231 and MCF-7 were transfected with let-7a mimics with or without CCL18 simulation. The expression level of let-7a was evaluated with qRT-PCR. Our study examined cell proliferation, migration and cell cycles following let-7a treatment. The predicted target of let-7a was identified and confirmed in vitro by a dual luciferase reporter system. The associations between let-7a, CCL18 and target gene expression were evaluated using RT-PCR and the Western blotting method. RESULTS: The downregulated expression level of let-7a was observed in both breast cancer cell lines. When compared to the control and CCL18 stimulation groups, cell proliferation and migration in MDA-MB-231 and MCF-7 cells were significantly inhibited by let-7a. Furthermore, the cell cycle was dramatically blocked at the G2/M phase. The luciferase reporter identified Lin28 as the direct binding target of let-7a in both breast cancer cell lines. CONCLUSION: Upregulation of let-7a carries the potential to reverse CCL18 induced cell proliferation and migration alteration in breast cancer cells by regulating Lin28 expression. Our results provided evidence which suggests the use of let-7a as a therapeutic agent in the treatment of breast cancer.

MicroRNA-708 is downregulated in hepatocellular carcinoma and suppresses tumor invasion and migration.

BACKGROUND: MicroRNA-708 (miR-708) has been identified as one of down-regulated miRNAs in hepatocellular carcinoma (HCC) tissues by Taqman miRNAs array and confirmed quantitatively by reverse transcription polymerase chain reaction (qRT-PCR). However, its involvement in HCC remains unclear. The aim of this study was to investigate the roles of miR-708 in carcinogenesis and cancer progression of HCC. MATERIALS AND METHODS: QRT-PCR was performed to detect the expression of miR-708 in 100 pairs of HCC and adjacent non cancerous tissues. Then, its associations with various clinicopathological features of HCC patients were statistically evaluated. After that, we also observed the effects of enforced miR-708 expression on migration and invasion of HCC cells in vitro. RESULT: Our data confirmed that the expression level of miR-708 in HCC tissues was significantly lower than those in adjacent non-cancerous tissues (P=0.001). In addition, low miR-708 expression was found to be closely correlated with high Edmondson-Steiner grading (P=0.02) and advanced Tumor Node Metastasis (TNM) stage (P=0.01). Furthermore, the enforced expression of miR-708 could suppress the migration and invasion of HCC cell lines in vitro. CONCLUSION: Our findings support that miR-708, which is frequently down-regulated in HCC, may contribute to the aggressive progression of HCC and inhibit HCC cell mobility. Further studies on the identification of its target genes are required to be performed.

Lower gastrointestinal bleeding: role of 64-row computed tomographic angiography in diagnosis and therapeutic planning.

AIM: To determine the value of computed tomographic angiography (CTA) for diagnosis and therapeutic planning in lower gastrointestinal (GI) bleeding. METHODS: Sixty-three consecutive patients with acute lower GI bleeding underwent CTA before endovascular or surgical treatment. CTA was used to determine whether the lower GI bleeding was suitable for endovascular treatment, surgical resection, or conservative treatment in each patient. Treatment planning with CTA was compared with actual treatment decisions or endovascular or surgical treatment that had been carried out in each patient based on CTA findings. RESULTS: 64-row CTA detected active extravasation of contrast material in 57 patients and six patients had no demonstrable active bleeding, resulting in an accuracy of 90.5% in the detection of acute GI bleeding (57 of 63). In three of the six patients with no demonstrable active bleeding, active lower GI bleeding recurred within one week after CTA, and angiography revealed acute bleeding. The overall location-based accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for the detection of GI bleeding by 64-row CTA were 98.8% (249 of 252), 95.0% (57 of 60), 100% (192 of 192), 100% (57 of 57), and 98.5% (192 of 195), respectively. Treatment planning was correctly established on the basis of 64-row CTA with an accuracy, sensitivity, specificity, PPV and NPV of 98.4% (248 of 252), 93.3% (56 of 60), 100% (192 of 192), 100% (56 of 56), and 97.5% (192 of 196), respectively, in a location-based evaluation. CONCLUSION: 64-row CTA is safe and effective in making decisions regarding treatment, without performing digital subtraction angiography or surgery, in the majority of patients with lower GI bleeding.

Genetic variability of ERCC1 genes in NER pathway influences the treatment outcome of gastric cancer.

We conducted a prospective study to analyze whether six SNPs in ERCC1 gene could serve as potential biomarkers for prognosis of gastric cancer. Between January 2010 and December 2012, 270 patients with pathologically proven gastric cancer and receiving platinum-based chemotherapy were recruited in our study. Genotyping of the ERCC1 rs11615, rs2298881, rs3212955, rs3212961, rs3212986 and rs735482 were carried out using the Sequenom MassARRAY platform. By logistic regression analysis, patients carrying the GT and TT genotypes of rs3212986 showed a significantly poorer response to chemotherapy than did those carrying the GG genotype, and the ORs (95% CI) were 0.47 (0.25-0.88) and 0.18 (0.08-0.41), respectively. By Cox proportional hazards models, the GT and TT genotypes of rs3212986 were correlated with increased risk of death when compared with the GG genotype, and the adjusted HRs (95% CIs) were 1.79 (1.01-3.16) and 2.57 (1.18-5.62), respectively. However, we did not find significant association between ERCC1 rs11615, rs2298881, rs3212955, rs3212961 and rs735482 and response to chemotherapy and overall survival in patients with gastric cancer. In conclusion, the results of the present retrospective study indicate that there is a significant difference in biological behavior between ERCC1 rs3212986 gene polymorphism and treatment outcome of gastric cancer.

Ginkgo biloba extract induce cell apoptosis and G0/G1 cycle arrest in gastric cancer cells.

OBJECTIVE: Previous studies have shown that the Ginkgo biloba extract (EGb761) can be used to anti-cancer. However, the mechanism by which EGb761 mediate this effect is still unclear. In the present study, EGb761 inhibited cell proliferation and induced cell apoptosis in gastric cancer cell was explored. METHODS: The cell viability was detected by the CCK8 assay. The cell cycle and apoptosis was assessed by flow cytometry. The protein expression of caspase-3, p53 and Bcl-2 were analyzed by western blot. RESULTS: Treatment of human gastric cancer cells with EGb761 induced cell death in a dose-dependent manner by using CCK8 assay. Consistent with the CCK8 assay, the flow cytometry results showed that gastric cancer cells were accumulated in G0/G1 phase when exposed to EGb761. Furthermore, the proportion of apoptosis cells was increased after EGb761 treatment as compared to untreated group. In addition, our results showed that the treatment of AGS cells with EGb761 significantly increased the expression of caspase3 and p53, and decreased the anti-apoptotic Bcl-2 level. CONCLUSIONS: Our results demonstrated that EGb761 could inhibit gastric cancer proliferation through adjusting cell cycle and inducing cell apoptosis.

[Expression of liver-intestine cadherin and its significance in hepatocellular carcinoma].

OBJECTIVE: To explore the expression and clinical significance of LI (liver-intestine)-cadherin mRNA and protein expression level in hepatocellular carcinoma. METHODS: Reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemical techniques were used to detect the expression of the LI-cadherin mRNA and protein in 56 cases of hepatocellular carcinoma, 44 cases of corresponding paracancerous tissues and 9 cases of normal liver tissues. The relationships with its clinicopathological characteristics were analyzed. RESULTS: The mRNA of LI-cadherin was expressed in 56 cases of hepatocellular carcinoma tissues and 44 cases of corresponding paracancerous tissues. But its expression was not detected in normal tissues. Semiquantitative analysis showed that the mRNA expression level of LI-caherin was greater in hepatocellular carcinoma tissues than that in corresponding paracancerous tissues (0.653 ± 0.147 vs 0.534 ± 0.138). The differences were statistically significant (P < 0.01). The positive rates of LI-cadherin protein were 64.29% (36/56) in hepatocellular carcinoma tissues, 22.73% (10/44) in paracancerous tissues and 0% (0/9) in normal tissues. CONCLUSION: The expression of LI-cadherin is up-regulated significantly in HCC. The over-expression of LI-cadherin protein is correlated with the lymph node metastasis and tumor thrombi in portal vein. It indicates that LI-cadherin may play an important role in the progression and metastasis of HCC.