April - June 2022, Volume 18, Issue 2

Kiba T

Overexpression of PDX-1 Gene Increases INS1 Gene Mrna Expression, Not INS2 Gene MRNA Expression, in Insulinoma Cell Line RIN-5F

Acta Endo (Buc) 2022, 18 (2): 164-167
doi: 10.4183/aeb.2022.164

Objective. Insulinoma is one of the functional neuroendocrine tumors, which induce hypoglycemia caused by inadequate high secretion of insulin. In rats, two genes coding for insulin, insulin 1 (Ins1) and insulin 2 (Ins2) are found on chromosome 1. Some structural feature studies have shown that Ins1 was generated from a transcript of Ins2 and was inserted into the genome by an RNA-mediated duplication–transposition event. Methods. In this study, the author has investigated how the expression of insulin genes, Ins 1 and Ins2, are altered by Pdx-1 gene overexpression in the insulinoma cell line, Rin-5F. Results. Overexpression of the Pdx-1 gene increases Ins1 gene mRNA expression, not Ins2 gene mRNA expression, in the insulinoma cell line. Thus, levels of the rat insulin 1 and insulin 2 peptides may be changed under specific conditions. Conclusions. This is the first report that Ins1, but not Ins2, is significantly increased by Pdx-1 gene overexpression in the insulinoma cell line. This could indicate more research and analysis of insulinoma tumorigenesis and Pdx-1 gene expression.

Keywords: Ins1, Ins2, Insulinoma, Pdx-1, Rin-5F.

Correspondence: Takayoshi Kiba MD, Okayama University of Science, Faculty of Science, Department of Life Sciences, Rika Daigaku, 1-1 Ridai-Cho, Kita-Ku, Okayama, 700-0005, Japan, E-mail: takkiba@hotmail.com