Reduced expression of circulating microRNA-218 in gastric cancer and correlation with tumor invasion and prognosis

AIM:To investigate the expression of microRNA-218(miR-218)in serum from gastric cancer patients and its relationship with clinicopathological characteristics.METHODS:A total of 68 patients with pathologically diagnosed gastric cancer and 56 healthy individuals were recruited to this study.The expression of miR-218was detected in the serum of gastric cancer patients and healthy individuals by quantitative real-time polymerase chain reaction.The clinical data were collectedand analyzed by statistical software.RESULTS:miR-218 was reduced significantly in the serum of gastric cancer patients compared to healthy individuals(1.15±0.08 vs 0.37±0.023;P=0.026).In the gastric cancer group,serum expression of miR-218was lower in patients with metastasis and poorly differentiated cancer compared with non-metastatic and well-differentiated cancer(0.19±0.011 vs 0.45±0.021,P=0.031 and 0.21±0.019 vs 0.49±0.021,P=0.025).Serum miR-218 was found to be significantly associated with gastric cancer metastasis(P=0.003),tumor T stage(P=0.018)and tumor grade(P=0.012).Low serum expression of miR-218 was related to an increase in the stage of gastric cancer.The expression level of miR-218 in the serum was correlated with the3-year survival.Ninety-seven percent of patients with a high level of miR-218 expression survived for 3 years,while only 54%of those with low miR-218 expression survived.CONCLUSION:miR-218 is deregulated in gastric cancer patients and is strongly correlated with tumor stage,grade and metastasis.Serum expression of miR-218 may be a prognostic marker.     

Different MicroRNA Expression Levels in Gastric Cancer Depending on Helicobacter pylori Infection

Background/AimsThis study was conducted to identify microRNAs (miRNAs) that are differentially expressed in Helicobacter pylori-infected patients with an intestinal type of gastric cancer using miRNA microarray and to confirm the candidate miRNA expression levels.MethodsTotal RNA was extracted from the cancerous and noncancerous regions of formalin-fixed, paraffin-embedded tissues of H. pylori-positive (n=8) or H. pylori-negative (n=8) patients with an intestinal type of gastric cancer. RNA expression was analyzed using a 3,523 miRNA profiling microarray based on the Sanger miRBase. Validation analysis was performed using TaqMan miRNA assays.ResultsA total of 219 miRNAs in the aberrant miRNA profiles across the miRNA microarray showed at least a 2-fold change differential expression in H. pylori-positive and H. pylori-negative cancer tissues. After candidate miRNAs were selected using online miRNA databases, TaqMan miRNA assays confirmed that three miRNAs (miR-99b-3p, miR-564, and miR-638) were significantly increased in three H. pylori-positive cancer tissues compared to the H. pylori-negative cancer tissues. Additionally, four miRNAs (miR-204-5p, miR-338-5p, miR-375, and miR-548c-3p) were significantly increased in H. pylori-negative cancer tissues compared to H. pylori-positive cancer tissues.ConclusionsmiRNA expression in the intestinal type of H. pylori infection-dependent gastric cancer suggests that different gastric cancer pathogenesis mechanisms could exist between H. pylori-positive and H. pylori-negative gastric cancer. Additional functional studies are required.     

H. pylori eradication did not improve dysregulation of specific oncogenic miRNAs in intestinal metaplastic glands

Background

Many microRNAs (miRNAs) are differentially expressed in Helicobacter pylori-infected gastric mucosa and in gastric cancer tissue.

Aim

We aimed to compare the effect of H. pylori eradication on gastric mucosal miRNAs in subjects in a high-risk group for gastric cancer compared to controls.

Methods

Patients with a recent history of endoscopic resection for early gastric cancer and sex- and age-matched non-cancer controls were enrolled. The expression of 21 miRNAs was examined using gastric mucosal biopsy specimens and microdissected gastric glands from the lesser and greater curvatures of the gastric corpus both before and one?year after H. pylori eradication.

Results

Twenty patients and 14 controls were enrolled. The expression of oncogenic miRNAs (miR-17/92 and the miR-106b-93-25 cluster, miR-21, miR-194, and miR-196) was significantly higher in the gastric mucosa of the cancer group than in the controls. H. pylori eradication resulted in a significant fall in the expression of oncogenic miRNAs only in the controls, whereas miR-223 expression was decreased and let-7d expression was increased in both groups. miR-196 was expressed only in intestinal metaplastic glands. The expression of oncogenic miRNAs was significantly higher in the intestinal metaplastic glands than in the non-intestinal metaplastic glands irrespective of H. pylori eradication. In neither group did H. pylori eradication significantly change any miRNA expression in the intestinal metaplastic glands.

Conclusion

Dysregulation of specific miRNAs is present in H. pylori-induced corpus gastritis. H. pylori eradication improved miRNA dysregulation, but not in intestinal metaplastic glands or in the gastric mucosa of patients in a high-risk group for gastric cancer.     

Cytoreductive surgery and intraperitoneal chemotherapy for colorectal peritoneal metastases

AIM: To systematically review the available evidence regarding cytoreductive surgery (CRS) and intraperitoneal chemotherapy (IPC) for colorectal peritoneal metastases (CPM).METHODS: An electronic literature search was carried out to identify publications reporting oncological outcome data (overall survival and/or disease free survival and/or recurrence rates) following CRS and IPC for treatment of CPM. Studies reporting outcomes following CRS and IPC for cancer subtypes other than colorectal were only included if data were reported independently for colorectal cancer-associated cases; in addition studies reporting outcomes for peritoneal carcinomatosis of appendiceal origin were excluded.RESULTS: Twenty seven studies, published between 1999 and 2013 with a combined population of 2838 patients met the predefined inclusion criteria. Included studies comprised 21 case series, 5 case-control studies and 1 randomised controlled trial. Four studies provided comparative oncological outcome data for patients undergoing CRS in combination with IPC vs systemic chemotherapy alone. The primary indication for treatment was CPM in 96% of cases (2714/2838) and recurrent CPM (rCPM) in the remaining 4% (124/2838). In the majority of included studies (20/27) CRS was combined with hyperthermic intraperitoneal chemotherapy (HIPEC). In 3 studies HIPEC was used in combination with early post-operative intraperitoneal chemotherapy (EPIC), and 2 studies used EPIC only, following CRS. Two studies evaluated comparative outcomes with CRS + HIPEC vs CRS + EPIC for treatment of CPM. The delivery of IPC was performed using an “open” or “closed” abdomen approach in the included studies.CONCLUSION: The available evidence presented in this review indicates that enhanced survival times can be achieved for CPM after combined treatment with CRS and IPC.     

Down-regulation of miR-141 in gastric cancer and its involvement in cell growth

Purpose  Human microRNA-141 (miR-141), a member of the miR-200 family, has been reported to be associated with various human malignancies. However, it remains unknown whether miR-141 is involved in the pathogenesis of gastric cancer. Therefore, we examined the expression of miR-141 in gastric cancer tissues and the effect of miR-141 overexpression on cancer cell proliferation. Methods  The expression level of miR-141 in 35 pair-matched gastric neoplastic and adjacent non-neoplastic tissues, and in 5 gastric cancer cell lines were examined by quantitative real-time PCR. The growth of MGC-803 cells transfected with miRNA precursor was examined by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazoliumbromide) assay. Results  MiR-141 was significantly down-regulated in 80% (28/35) of primary gastric cancer tissues compared with pair-matched adjacent non-tumor tissues (P < 0.01). The expression of miR-141 was also found to be substantially reduced in several human gastric cancer cell lines such as MGC-803, HGC-27, SGC-7901 and BGC-823 cells. Overexpression of miR-141 with its precursors significantly inhibited the proliferation of gastric cancer cells. Conclusions  These results suggest that miR-141 may be involved in the development of gastric cancer through its inhibitory effect on cell proliferation. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

miR-29a up-regulation in AR42J cells contributes to apoptosis via targeting TNFRSF1A gene

AIM: To investigate the expression of mi R-29 a in rat acute pancreatitis and its functional role in AR42 J cell apoptosis.METHODS: Twelve SD rats were divided into a control group and an acute edematous pancreatitis(AEP) group randomly. AEP was induced by intraperitoneal injection of L-arginine(150 mg/kg) in the AEP group and equal volume of 0.9% Na Cl was injected in the control group. The apoptosis of acinar cells in pancreatic tissue was determined by TUNEL assay. mi RNA chip assay was performed to examine the expression of mi RNAs in two groups. Besides, to further explore the role of mi R-29 a in apoptosis in vitro, recombinant rat TNF-α(50 ng/m L) was administered to treat the rat pancreatic acinar cell line AR42 J for inducing AR42 J cell apoptosis. Quantitative real-time PCR(q RT-PCR) was adopted to measure mi R-29 a expression. Then, mi RNA mimic, mi RNA antisense oligonucleotide(AMO) and control vector were used to transfect AR42 J cells. The expression of mi R-29 a was confirmed by q RT-PCR andthe apoptosis rate of AR42 J cells was detected by flow cytometry analysis. Western blot was used to detect the expression of activated caspase3. Moreover, we used bioinformatics software and luciferase assay to test whether TNFRSF1 A was the target gene of mi R-29 a. After transfection, q RT-PCR and Western blot was used to detect the expression of TNFRSF1 A in AR42 J cells after transfection.RESULTS: The expression of mi R-29 a was much higher in the AEP group compared with the control group as displayed by the mi RNA chip assay. After inducing apoptosis of AR42 J cells in vitro, the expression of mi R-29 a was significantly increased by 1.49 ± 0.04 times in comparison with the control group. As revealed by q RT-PCR assay, the expression of mi R-29 a was 2.68 ± 0.56 times higher in the mi R-29 a mimic group relative to the control vector group, accompanied with an obviously increased acinar cell apoptosis rate(42.83 ± 1.25 vs 24.97 ± 0.15, P 0.05). Moreover, the expression of mi R-29 a in the mi RNA AMO group was 0.46 ± 0.05 times lower than the control vector group, and the cell apoptosis rate was much lower accordingly(17.27 ± 1.36 vs 24.97 ± 0.15, P 0.05). The results of bioinformatics software and luciferase assay showed that TNFRSF1 A might be a target gene of mi R-29 a. TNFRSF1 A expression was up-regulated in the mi R-29 a mimic group, while the mi R-29 a AMO group showed the reverse trend.CONCLUSION: mi R-29 a might promote the apoptosis of AR42 J cells via up-regulating the expression of its target gene TNFRSF1 A.     

MicroRNA-21 regulates expression of the PTEN tumor suppressor gene in human hepatocellular cancer

BACKGROUND AND AIMS: microRNAs (miRNAs) are short noncoding RNAs that regulate gene expression negatively. Although a role for aberrant miRNA expression in cancer has been postulated, the pathophysiologic role and relevance of aberrantly expressed miRNA to tumor biology has not been established. METHODS: We evaluated the expression of miRNA in human hepatocellular cancer (HCC) by expression profiling, and defined a target gene and biologically functional effect of an up-regulated miRNA. RESULTS: miR-21 was noted to be highly overexpressed in HCC tumors and cell lines in expression profiling studies using a miRNA microarray. Inhibition of miR-21 in cultured HCC cells increased expression of the phosphatase and tensin homolog (PTEN) tumor suppressor, and decreased tumor cell proliferation, migration, and invasion. In contrast-enhanced miR-21 expression by transfection with precursor miR-21 increased tumor cell proliferation, migration, and invasion. Moreover, an increase in cell migration was observed in normal human hepatocytes transfected with precursor miR-21. PTEN was shown to be a direct target of miR-21, and to contribute to miR-21 effects on cell invasion. Modulation of miR-21 altered focal adhesion kinase phosphorylation and expression of matrix metalloproteases 2 and 9, both downstream mediators of PTEN involved in cell migration and invasion. CONCLUSIONS: Aberrant expression of miR-21 can contribute to HCC growth and spread by modulating PTEN expression and PTEN-dependent pathways involved in mediating phenotypic characteristics of cancer cells such as cell growth, migration, and invasion.     

血管紧张素Ⅱ和Ⅳ对心血管系统的共同调节

肾素血管紧张素系统(RAS)是心血管疾病的主要调节因素,其核心成分血管紧张素Ⅱ(AngⅡ)不仅可以直接收缩血管、调节血压,还与炎症、内皮细胞功能失调、动脉粥样硬化、高血压、心力衰竭等疾病密切相关。以前大多数研究集中于AngⅡ的功能,以此为靶点生产的AT1受体抑制剂及血管紧张素转换酶Ⅰ抑制剂在心血管疾病的临床治疗中发挥了重要的作用。但是近年来的研究发现,RAS其他成员如Ang(1-7)、AngⅣ有着各自独立的生物学效应,这提示RAS是一个远比我们以往认识     

Growth inhibition of hepatocellular carcinoma tumor endothelial cells by miR-204-3p and underlying mechanism

AIM:To investigate the mechanism by which miR-204-3p inhibits the growth of hepatocellular carcinoma(hCC)tumor endothelial cells(TECs).METHODS:Flow cytometry was used to identify hCCTECs and analyze their purity.Differentially expressed miRNAs in hCC TECs as compared to normal hepatic sinusoidal endothelial cells(hSECs)were examined using the hmiOA v4 human miRNA OneArray?microarray.miR-204-3p showed the most significant decrease in expression and was further studied.Over-expression of miR-204-3p was achieved using lentiviral transduction into TECs of hCC.The biological changes in hCC TECs before and after transduction were detected using MTT and apoptosis assays.The association between miR-204-3p and fibronectin 1(FN1)was determined using the dual luciferase activity assay.Changes in FN1protein expression before and after transduction were detected using Western blot analysis.RESULTS:Microarray results showed that compared to normal hSECs,15 miRNAs were differentially expressed in hCC TECs,including 6 miRNAs with increased expression and 9 miRNAs with decreased expression.Among them,miR-204-3p showed the most significant decrease in expression(log2=-1.233477,P=0.000307).Over-expression of miR-204-3p in hCC TECs via lentiviral transduction significantly inhibited the proliferation of hCC TECs and promoted apoptosis.Results from the dual luciferase activity experiment showed that the luciferase intensity in the wild type FN1 group was significantly inhibited(P<0.05),while that in the mutant FN1 group was not obviously affected.This observation indicated that FN1 was one of the potential targets of miR-204-3p.After over-expression of miR-204-3p in hCC TECs,Western blot analysis showed that the expression of FN1 protein was significantly inhibited.CONCLUSION:MiR-204-3p acts on its potential target gene,FN1,and inhibits its expression,thus blocking the adhesion function of FN1 in promoting the growth of TECs.