SH3BP2 Silencing Increases miRNAs Targeting ETV1 and Microphthalmia-Associated Transcription Factor, Decreasing the Proliferation of Gastrointestinal Stromal Tumors

Elizabeth Proaño-Pérez; Eva Serrano-Candelas; Cindy Mancia; Arnau Navinés-Ferrer; Mario Guerrero; Margarita Martin

doi:10.3390/cancers14246198

SH3BP2 Silencing Increases miRNAs Targeting ETV1 and Microphthalmia-Associated Transcription Factor, Decreasing the Proliferation of Gastrointestinal Stromal Tumors

Cancers (Basel). 2022 Dec 15;14(24):6198. doi: 10.3390/cancers14246198.

Authors

Elizabeth Proaño-Pérez^{1

2

3}, Eva Serrano-Candelas^{1

2}, Cindy Mancia¹, Arnau Navinés-Ferrer^{1

2}, Mario Guerrero¹, Margarita Martin^{1

2}

Affiliations

¹ Biochemistry and Molecular Biology Unit, Biomedicine Department, Faculty of Medicine and Health Sciences, University of Barcelona, 08036 Barcelona, Spain.
² Clinical and Experimental Respiratory Immunoallergy (IRCE), Institut d'Investigacions Biomediques August Pi i Sunyer (IDIBAPS), 08036 Barcelona, Spain.
³ Faculty of Health Sciences, Technical University of Ambato, Ambato 180105, Ecuador.

Abstract

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the gastrointestinal tract. Gain of function in receptor tyrosine kinases type III, KIT, or PDGFRA drives the majority of GIST. Previously, our group reported that silencing of the adaptor molecule SH3 Binding Protein 2 (SH3BP2) downregulated KIT and PDGFRA and microphthalmia-associated transcription factor (MITF) levels and reduced tumor growth. This study shows that SH3BP2 silencing also decreases levels of ETV1, a required factor for GIST growth. To dissect the SH3BP2 pathway in GIST cells, we performed a miRNA array in SH3BP2-silenced GIST cell lines. Among the most up-regulated miRNAs, we found miR-1246 and miR-5100 to be predicted to target MITF and ETV1. Overexpression of these miRNAs led to a decrease in MITF and ETV1 levels. In this context, cell viability and cell cycle progression were affected, and a reduction in BCL2 and CDK2 was observed. Interestingly, overexpression of MITF enhanced cell proliferation and significantly rescued the viability of miRNA-transduced cells. Altogether, the KIT-SH3BP2-MITF/ETV1 pathway deserves to be considered in GIST cell survival and proliferation.

Keywords: ETV1; MITF; SH3BP2; cell cycle; cell survival; gastrointestinal stromal tumors; miRNA.

Abstract

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