8th Euro Global Summit on Cancer Therapy
Anglia Ruskin University, UK
Title: The CCCTC binding factor (CTCF) may not directly regulate ERα mRNA expression in the ER+ MCF7 breast cancer cell line
Biography: Okezie Ofor
Introduction: CTCF is an evolutionally conserved 11-zinc fi nger protein factor involved in an extensive array of cellular activities whose de-regulation could lead to cellular transformation via interactions with ER-α binding regions and ER-regulated genes, CTCF was shown to compartmentalize the cellular genome into domains. Furthermore it was found co-localized to ER-α in MCF7 cells and had interactions with ER-α during histone deacetylase recruitment and fork-head activity. It is not clear what the regulatory relationship between CTCF and ER-α could be. Aim: To determine whether CTCF expression regulated ER-α expression in the ER+ MCF7 breast cancer cell line. Methods: MCF7 breast cancer cells were transfected with either CTCF expression vectors or si-RNA against CTCF. Following CTCF over-expression and knock-down, changes in endogenous expression of ER-α gene and protein expression were monitored by quantitative polymerase chain reaction (QPCR) and western blot analysis respectively. Results: CTCF plasmid over-expression and si-RNA knockdown was associated with cell rounding but with 96.4% and 95.7% cell viability respectively. Increase in CTCF mRNA on over-expression was associated with a rise in CTCF protein expression. Si-RNA knockdown of CTCF mRNA was accompanied by a corresponding decrease in CTCF protein expression. CTCF over-expression and knockdown appeared to inhibit the ability to detect ER-α protein expression by western blotting. Neither the over-expression nor knockdown of CTCF altered ER-α mRNA expression as detected by QPCR. Conclusion: Alterations in CTCF mRNA expression did not aff ect ER-α gene expression in MCF7 breast cancer cell line suggesting that CTCF may not directly regulate ER-α mRNA expression.