NATURAL ANTISENSE TRANSCRIPTS IN THE REGULATION OF ACSL4 EXPRESSION IN BREAST CANCER CELLS

ORLANDO, ULISES; MORDUCHOWICZ, NATALIA; CASTILLO, ANA FERNANDA; PODESTÁ, ERNESTO J

Córdoba

Congreso; 52 Annual Meeting Argentine Society for Biochemistry and Molecular Biology; 2016

Sociedad Argentina de Investigación en Bioquímica y Biología Molecular (SAIB)

Acyl-CoA synthetase 4 (ACSL4) is overexpressed in human breast cancer cells and promotes tumor aggressiveness. The mechanisms that regulate its expression are not fully characterized. Natural antisense transcripts (NATs) are endogenous RNAs complementary to mRNA, which regulate their counterparts and play a role in human diseases. We identified a murine ACSL4-NAT, a hormonally-regulated long non-coding RNA that may influence steroidogenesis through ACSL4 expression regulation. The aim was to evaluate the participation of NATs in regulating human ACSL4 expression in breast cancer cell model. By BLAST algorithm, we compared murine ACSL4-NAT sequence against human ACSL4 mRNA, obtaining a 92% identity and 94% complementary. Using RNA from human breast cancer MCF-7 and MDA-MB-231 cells, sequence-specific RT-PCR experimentally demonstrated the existence of such human ACSL4-NAT. We amplified a fragment of the expected size in both cell lines and observed coordinated expression of ACSL4 NAT and mRNA, with a higher expression of in the more aggressive MDA-MB-231 cells. By 5 ́and 3 ́RACE we obtained the complete sequence of this transcript. ACSL4-NAT knockdown via asymmetric shRNA impacted on mRNA and protein levels and cell proliferation. NATs could be part of the mechanism regulating ACSL4 expression and thus contributing to the development of aggressive phenotype in breast cancer cells.