Nuclear Sp1 and Sp1 oligonucleotide binding increased following carrageenan and ARSB silencing.
A, in the NCM460 cells, nuclear Sp1 was significantly increased following exposure to carrageenan or ARSB silencing by siRNA (p < 0.001). Galectin-3 silencing did not inhibit the increase in the nuclear Sp1. ARSB silencing produced greater increase in nuclear Sp1 than carrageenan exposure (p < 0.01; 2.98 times control versus 2.26 times control). B, in NCM460 cells, oligonucleotide binding assay demonstrated an increase in Sp1 binding to the Sp1 oligonucleotide consensus sequence following ARSB silencing (p < 0.001). This increase was inhibited when galectin-3 was silenced. Addition of exogenous Sp1 wild-type consensus oligonucleotide completely inhibited the nuclear Sp1 binding as detected by Sp1 antibody. Baseline binding was unaffected by addition of mutated Sp1 consensus oligonucleotide. C, In HT-29 cells, oligonucleotide binding assay indicated an increase in Sp1 binding to the Sp1 oligonucleotide consensus sequence following ARSB silencing (p < 0.001) and inhibition when galectin-3 was silenced. CGN, carrageenan; oligo, oligonucleotide; si, siRNA; WT, wild-type; ND, no difference.