Figure 4From: TNK2 preserves epidermal growth factor receptor expression on the cell surface and enhances migration and invasion of human breast cancer cells Downregulation of TNK2 by siRNA inhibits human breast cancer cell migration. (a) MDA-MB-231 cells treated with TNK2 targeting SiRNA (S1, S3) had less ability to migrate relative to the nontargeting SiRNA control (N) as measured by a scratch-would healing assay. There was a significant difference between nontargeting SiRNA control (N) and TNK2-targeting SiRNA (S1) at 4, 8 and 24 hours (P = 0.0195, P = 0.0004 and P = 0.0002, respectively). There was a significant difference between nontargeting SiRNA control siRNA (N) and TNK2-targeting SiRNA (S3) at 8 hours (P = 0.032). Lower panels: representative pictures of the scratch-would assays 48 hours following wounding. (b) Proliferation as measured by an Alamar Blue assay was not significantly affected in cells treated with the TNK2-targeting SiRNA (S1, S3) relative to the nontargeting control siRNA (N) over a period of 72 hours. (c) Caspase-dependent apoptosis as measured by a caspase-3 cleavage assay showed no significant difference between cells treated with the TNK2-targeting SiRNA (S1, S3) relative to the nontargeting control siRNA (N) over a period of 72 hours. Taxol is used as a positive control (TAX) and showed significant differences in all cases. (d) There was no significant difference seen for caspase-independent apoptosis as measured by Hoechst staining between cells treated with the TNK2-targeting SiRNA (S1, S3) relative to the nontargeting control siRNA (N) over a period of 72 hours. Taxol is used as a positive control (TAX) and showed significant differences in all cases. *P ≤ 0.05, **P ≤ 0.01, ***P ≤ 0.001.Back to article page