Page 119 - ebook HCC

PROGRAMME AND ABSTRACTSAND ABSTRACTS
GENEV
EASL
116
116 PROGRAMME GENEVA, SWITZERLANDA, SWITZERLAND EASL HCC SUMMITHCC SUMMIT 117
117
FEBRUARY 13 - 16, 2014Y 13 - 16, 2014
FEBRUAR
Poster Board Number B16
UNSHIELDING IGF-II MRNA BY TARGETING
IGF2BP-2 AND 3 THROUGH DEMETHYLATING
THE MICRO-RNA LET-7A-3 GENE IN
HEPATOCELLULAR CARCINOMA CELL LINES

Amr Waly , Hend El Tayebi , Karim Hosny , Gamal Esmat , Ahmed Abdelaziz 1 Results: Knocking down IGF2BP-2 and 3 resulted in a significant down-regulation in IGF-
3
2
1
1
1 The Molecular Pathology Research Group, German University in Cairo, II mRNA expression. In addition, demethylation caused significant up-regulation in let-7a
2 Department of General Surgery, Faculty of Medicine, Cairo University, and concomitant significant down-regulation in IGF-II. Also, forcing the expression of let-
3 Department of Endemic Medicine and Hepatology, Cairo University, cairo, Egypt 7a resulted in a significant down-regulation in IGF-II mRNA. Forcing let-7a expression
resulted in significant down-regulation of both IGF2BP-2 and 3 while let-7a inhibitors
Corresponding author’s e-mail: dr.amrwaly@gmail.com resulted in significant restoration of their expression.
Conclusions: IGF-II is shielded and stabilized by IGF2BP-2 and 3 in HCC. In addition,
Introduction: Insulin-like Growth Factor-II (IGF-II) is a strong mitogen with established we proved that let-7a is an epigenetically regulated miRNA. Also, let-7a has an indirect
oncogenic effects in Hepatocellular Carcinoma (HCC). IGF-II expression is regulated by impact on IGF-II through targeting the IGF-II regulators, IGF2BP-2 and 3.
a family of three RNA-binding proteins: the IGF-II mRNA-Binding Proteins (IGF2BPs).
IGF2BPs have varying effects on IGF-II. IGF2BP-1 induces IGF-II mRNA decay while
IGF2BP-2 and 3 shield IGF-II mRNA against decay. Still, the IGF-II-IGF2BPs interplay
BASIC POSTER ABSTRACTS IGF-II and both IGF2BP-2 and 3 with promising scores. Our previous findings showed that BASIC POSTER ABSTRACTS
has never been investigated in HCC. Our in silico analysis predicted miR-let-7a to target
the tumor suppressor let-7a is down-regulated in HCC. We found that hypermethylation of
the let-7a-3 gene is responsible for this down-regulation. In addition, we found an inverse
correlation in the expression of let-7a and IGF-II, which highlights the regulatory effect(s)
let-7a might exert on IGF-II in HCC.

Aims: We aimed at investigating the regulatory role of IGF2BP-2 and 3 on IGF-II. In
addition, we aimed to investigate if the expression of let-7a can be relieved by the
demethylating drug, decitabine. Also, the regulatory impact of let-7a on IGF-II needed to be
further validated. Last but not least, the regulation of IGF2BP-2 and 3 in HCC by miRNAs
is still obscure, and thus we aimed at investigating the impact of let-7a on IGF2BP-2 and
3 and hence on IGF-II expression stability.

Methodology: The HCC cell lines Huh-7 were cultured, followed by: (1) transfection
with either: (a) let-7a mimics, (b) let-7a inhibitors, (c) siRNAs against IGF2BP-2 and 3,
or (2) treatment with decitabine for 5 days. That was followed by total RNA extraction,
followed by reverse transcription to complementary DNA (cDNA) and amplification and
quantification with Real-time PCR.