The Complex Network between MYC Oncogene and microRNAs in Gastric Cancer: An Overview

Abstract

Despite the advancements in cancer treatments, gastric cancer is still one of the leading causes of death worldwide. In this context, it is of great interest to discover new and more effective ways of treating this disease. Accumulated evidences have demonstrated the amplification of 8q24.21 region in gastric tumors. Furthermore, this is the region where the widely known MYC oncogene and different microRNAs are located. MYC deregulation is key in tumorigenesis in various types of tissues, once it is associated with cell proliferation, survival, and drug resistance. microRNAs are a class of noncoding RNAs that negatively regulate the protein translation, and which deregulation is related with gastric cancer development. However, little is understood about the interactions between microRNAs and MYC. Here, we overview the MYC role and its relationship with the microRNAs network in gastric cancer aiming to identify potential targets useful to be used in clinic, not only as biomarkers, but also as molecules for development of promising therapies.

Keywords: 8q24.21; MYC; gastric cancer; microRNA; target therapy.

Figure 1

The 8q24.21 genes. The coding genes are shown in green, and the non-coding genes in grey.

Figure 2

Pleiotropic consequence of MYC deregulation in cancer. MYC overexpression in gastric carcinogenesis affects various components of signaling pathways critical to cancer establishment. Some of these pathways’ phenotypes are shown here.

Figure 3

Pathways scheme in which miRNAs regulate MYC and PVT1 expression and vice versa in neoplastic gastric tissue samples and cell lines. The coding genes are shown in green, and the non-coding genes in grey. Lines ending with an arrow indicate activation, whereas T ending lines indicate repression. Lines with a red cross indicate that the interaction is lost due to repression or blocking of a miRNA or protein.