Baicalein Reduces Metastasis and Heightens Caspase-Induced Apoptosis in Human Colorectal Cancer Cells

Abstract

Current colorectal cancer (CRC) treatments exhibit unwanted cytotoxicity against healthy proliferating cells. Hence, these therapeutics demand higher specificity upon drug delivery, a task that may be facilitated by the discovery of anticancer agents bearing critical mechanisms of action. Baicalein is a flavonoid with promising anticancer activity, among other pharmacological benefits, and has therefore been of high clinical interest. We tested baicalein in vitro f or its effect on several CRC hallmarks, including the suppression of metastasis (the spread of cancer cells from their initial site), the ability to induce apoptosis (cell death), and the inhibition of proliferation (the growth of cells). The suppression of the metastasis of CRC cells was recorded via two studies: the cell migration assay and the in silico docking of baicalein with toll-like receptor 4 (TLR4) and matrix metalloproteinase-9 (MMP-9). Results from the cell migration assay showed that baicalein inhibited metastasis by up to 25.76% (p < 0 .01) in a concentration-dependent manner. We then reinforced these results by docking baicalein with TLR4 (binding affinity: -8.4 kcal/mol) and docking baicalein with MMP-9 (binding affinity: -7.9 kcal/mol), classifying strong binding affinities as those less than -6.0 kcal/mol. The induction of cell death was measured using a caspase activity assay. Again, a docking study was done to reinforce the findings from the primary in vitro experiment, though this time between baicalein and caspase-3 (binding affinity: -7.1 kcal/mol). Despite mixed observations in concentration dependence, caspase activity, relative to control, reached a maximal increase of 88.6% (p < 0 .01), and results from the MTT assay demonstrated a survival rate, relative to control, of as low as 59.64%. Considerations for future studies include the testing of baicalein in vivo and on more aberrative CRC cell lines.