Regulation of SELENOF translation by eIF4a3: Possible role in prostate cancer progression

Abstract

The levels of the SELENOF selenoprotein are dramatically reduced in prostate cancer compared to adjacent benign tissue and reducing SELENOF in prostate epithelial cells results in the acquisition of features of the transformed phenotype. It was hypothesized that the aberrant increase in the eiF4a3 translation factor, which has an established role in RNA splicing and the regulation of selenoprotein translation, contributes to the lower levels of SELENOF. Using the available databases, eIF4a3 messenger RNA (mRNA) levels are elevated in prostate cancer compared to normal tissue as is the hypomethylation of the corresponding gene. Using a prostate cancer tissue microarray, we established that eiF4a3 levels are higher in prostate cancer tissue. Ectopic expression of eIF4a3 in prostate cancer cells reduced SELENOF levels and attenuated the readthrough of the UGA codon using a specialized reporter construct designed to examine UGA decoding, with the opposite effects observed using eIF4a3 knock‐down constructs. Direct binding of eIF4a3 to the regulatory regions of SELENOF mRNA was established with pull‐down experiments. Lastly, we show that an eIF4a3 inhibitor, eIF4a3‐IN‐2, increases SELENOF levels, UGA readthrough, and reduces binding of eIF4a3 to the SELENOF mRNA 3′‐UTR in exposed cells. These data establish eIF4a3 as a likely prostate cancer oncogene and a regulator of SELENOF translation.

Document Details

Document Type
Pub Defense Publication
Publication Date
Aug 09, 2023
Source ID
10.1002/mc.23616

Entities

People

  • Alan M Diamond
  • Andre Kajdacsy‐balla
  • Eileen Brister
  • Irida Kastrati
  • John D Brockman
  • Klara Valyi‐nagy
  • Lenny K. Hong
  • Li Ping
  • Maria Sverdlov
  • Shrinidhi Kadkol
  • Soumen Bera
  • Virgilia Macais
  • Waleed Ali
  • Ziqiao Xu

Organizations

  • Albert Einstein College of Medicine
  • Loyola University Chicago
  • United States Department of Defense
  • University of Illinois at Chicago
  • University of Missouri

Tags

Fields of Study

  • Biology

Readers

  • Molecular Genetics
  • Prostate Cancer Biology.
  • Women's Health and Cancer Risk Research: African American Women and Pregnancy Outcomes.