Down-regulated miR-9 and miR-433 in human gastric carcinoma

Abstract

Background: MircoRNAs(miRNAs) are short, endogenously non-coding RNAs. The abnormal expression of miRNAs may be valuable for the diagnosis and treatment of tumors.

Hsa-miR-9 methylation status is associated with cancer development and metastatic recurrence in patients with clear cell renal cell carcinoma

“…In addition to analysis of hsa-miR-9 methylation status, microRNA expression studies have shown that hsa-miR-9 expression is downregulated for several cancer sites, including breast (Lehmann et al, 2008;Hsu et al, 2009) Hsa-miR-9 methylation and renal cell carcinoma MAT Hildebrandt et al gastric (Luo et al, 2009) and ovarian (Laios et al, 2008). Furthermore, studies of liver (Budhu et al, 2008), breast (Iorio et al, 2005) and colorectal (Bandres et al, 2009) cancers have shown that altered hsa-miR-9 expression was associated with metastatic tumors.…”

Aberrant hypermethylation ofmiR-9genes in gastric cancer

“…Similar findings indicate that miR-9 plays a tumor-suppressive role via repressing tumor-associated genes (NFκB1 and RAB34) in gastric cancer. 29,33 Significantly, in human cancers, miR-9 expression levels or methylation status are associated with several clinicopathological features, such as tumor grade, metastatic status and survival rate. 23,27,31 Contrary to the above results, it has been showed that miR-9 is significantly deregulated in breast cancer or colorectal cancer, with increasing cancer migration, through repression of α-cadherin or E-cadherin expression.…”

“…[23][24][25][26][27][28][29][30] Several lines of evidence have indicated that miR-9 can function as a tumor suppressor in various cancers. 23,24,27,29,[31][32][33] In gastric cancer, miR-9 is under-expressed and ectopic expression of miR-9 can influence cell growth and the cell cycle. 24,29,32,33 However, there is no study examining the mechanisms involved in the differential regulation of all three miR-9 gene loci.…”

“…23,24,27,29,[31][32][33] In gastric cancer, miR-9 is under-expressed and ectopic expression of miR-9 can influence cell growth and the cell cycle. 24,29,32,33 However, there is no study examining the mechanisms involved in the differential regulation of all three miR-9 gene loci. In this study, we explore the promoter methylation status of the miR-9-1, miR-9-2 and miR-9-3 gene loci in gastric cancer tissues.…”

MiR-375 frequently downregulated in gastric cancer inhibits cell proliferation by targeting JAK2

“…Although a number of miRNAs that are associated with gastric cancer have been identified to date, the role of many of them in tumorigenesis and the underlying mechanism remain to be determined. Recently, we and others have identified some miRNAs deregulated in gastric cancer, such as downregulation of miR-141, miR-143, miR-145, miR-9 and miR-218 [11][12][13][14], and upregulation of miR-21, miR-150 and 106a [15][16][17][18]. Nevertheless, until very recently, the function and regulation of these miRNAs in gastric cancer have hardly been explored.…”