Effect of REST on cancer invasiveness in MCF-7 and MDA-MB-231 cells using RNA-sequencing (RNA-seq) analysis .

We report a negative correlation of invasiveness with REST expression. In addition, one alternatively spliced product (ASP) of REST, REST-003, shows a positive correlation with invasiveness. REST has a well-established role in regulating transcription of genes important for neuronal development. Its role in cancer, though significant, is less well understood. We would like to investigate the effect of REST on invasive phenotype. In order to do so, we downregulate REST by siRNA treatment in weakly invasive MCF-7 breast cancer cells in which REST is expressed highly: 1) si-GAPDH (control), two si-RESTs (2)si-REST_1 and 3) si-REST_2). Conversely, we overexpress REST by transfection of wt-REST cDNA in highly invasive MDA-MB-231 cells in which REST is expressed at the low level: 4) EGFP (control), 5) mt-REST (another control) and 6) wt-REST. REST (repressor element-1 (RE-1) silencing transcription factor) contains a DNA-binding domain that is localized within eight zinc fingers and two repressor domains located at the N-terminal and C-terminal, respectively. REST suppresses expression of neural-specific genes. mt-REST lacks two repressor domains, so it can be used as a control for wt-REST. In contrast, REST-003 is one of alternatively spliced products (ASPs) of REST. Overall design: Downregulation of REST using two siRNAs in MCF-7 cells or overexpression of REST with wt- or mt-REST cDNA in MDA-MB-231 cells REST_ISOFORM_FIG1.pdf was provided to explain *rawRestIsoformCnts.txt files described in the README1.txt file.