Mansour Almouh - Department of Molecular Genetics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
Ali Khalafizadeh - Department of Molecular Genetics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
Zuhair Mohammad Hassan - Department of Immunology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
Sadegh Babashah - Department of Molecular Genetics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran

Backgrounds: Gastric cancer, known to be the leading cause of cancer mortality, is particularlycommon across Asia. MicroRNAs (miRNAs) are small non-coding RNAs, play a critical role inposttranscriptional gene regulation, related to cell survival, proliferation, differentiation,migration, metastasis, and invasion. Recently, the presence of human epidermal growth factorreceptor ۲ (HER۲; also known as ERBB۲) expression in advanced gastric cancer has played animportant role in treatment. In addition, it is known that ERBB۲ gene mutation overexpression,leading to HER۲, occurs early in carcinogenesis. Our study aimed to estimate the contribution ofselected dysregulated miRNAs to the pathogenesis of gastric cancer.Materials and Methods: In this theoretical study, based on bioinformatics analysis of miRNAs,by using the KEGG database we found that ERBB۲ is an oncogenic related to the signalingpathways involved in gastric cancer pathogenesis. The miRTargetLink (https://ccb-web.cs.unisaarland.de/mirtargetlink/) database was used to search the miRNAs that target the ERBB۲ gene.Then, we confirmed the suggested miRNAs by the online predictive tools such as DIANAmiRPath(http://diana.imis.athena-innovation.gr/DianaTools/), Targetscan(http://www.targetscan.org/vert_۷۲/) and OncomiR (http://www.oncomir.org/)Results: According to the results of this study, the ERBB۲ gene is the target of hsa-miR-۲۱-۵p,hsa-miR-۱۲۵b-۵p, and hsa-miR-۱۲۵a-۵p. Also, they can modulate the pathogenesis of gastriccancer by regulating ErbB and p۵۳ signaling pathways.Conclusion: The results of this study showed that miRNAs targeting the ERBB۲ gene areinvolved in key molecular pathways and biological processes of gastric cancer pathogenesis, andthey can be novel therapeutic options in future experimental researches on the field of gastriccancer.

Gastric cancer, miRNAs, Bioinformatics, ERBB۲