In addition, given that BC cell phenotype change observed in several studies suggesting therapeutic potential of HSP27 knockdown in BC [19, 28, 29] was dependent on a single OGX-427 siRNA (usually expected to have only transient suppressive effects), we hypothesized that long-term suppression of HSP27 by various shRNA sequences is more effective in inhibiting tumor growth and enhancing chemosensitivity of BC cells. Here, HSPB1 is linked to breast cancer.