Expression of BCL6 mRNA and protein in human breast cancer cell lines and tissue specimens. (a) qRT-PCR. Level of BCL6 mRNA expression in eight human mammary cell lines was analyzed by qRT-PCR. (b) qRT-PCR. Levels of BCL6 mRNA expression were examined in 30 breast cancer (BC) and 25 breast benign disease tissue specimens (BD) by qRT-PCR. (c) Representative imagines of BCL6 expression analyzed by in situ hybridization and immunohistochemistry (Magnification: ×400). (d) Kaplan-Meier curve of the relapse-free survival (RFS) or overall survival (OS) according to BCL6 expression.