Baicalein Regulates Colony Formation of Triple-negative Breast Cancer Cells by Inhibiting YAP Entry into Nucleus / 中国实验方剂学杂志

Objective:This study aims to observe the effect of baicalein on the clonal formation of triple negative breast cancer MDA-MB-231 and MDA-MB-468 cells， and to explore the mediation role of Yes- related protein （YAP） in it. Method:MDA-MB-231 and MDA-MB-468 cells were treated with baicalein. Thiazole blue （MTT） colorimetric method was used to detect cell proliferation ability. Plate cloning experiments was used to detect the colony forming ability. Immunofluorescence method was used to detect the nuclear distribution of YAP， and Western blot test was used to detect the protein expression levels of YAP large tumor suppressor factor 1 （LATS1）， YAP， phosphorylated Yes- related protein（p-YAP） and phosphorylated YAP large tumor suppressor factor 1 （p-LATS1）. Result:Compared with the blank group， baicalein （40， 80， 160 μmol·L^-1） significantly inhibited the proliferation ability of MDA-MB-468 and MDA-MB-231 cells （<italic>P</italic><0.05， <italic>P</italic><0.01）， and the inhibitory effect was dose-dependent. The half inhibit concentration（IC₅₀） of baicalein against MDA-MB-468 and MDA-MB-231 cells were （80.3±7.2），（70.4±6.5） μmol·L^-1， respectively. Compared with blank group， baicalein （5， 10， 20 μmol·L^-1） had no significant effect on the proliferation of MDA-MB-468 and MDA-MB-231 cells， and the difference was not statistically significant. Compared with the blank group， baicalein （5， 10， 20 μmol·L^-1） significantly dose-dependently reduced the cell colony formation rates of MDA-MB-468 and MDA-MB-231 cells （<italic>P</italic><0.05， <italic>P</italic><0.01）， and baicalein （10， 20 μmol·L^-1） significantly inhibited the nuclear expression of YAP in MDA-MB-468 and MDA-MB-231 cells in a dose-dependent manner（<italic>P</italic><0.01）. Also， baicalin （5， 10， 20 μmol·L^-1） significantly up-regulated p-YAP and p-LATS1 protein expressions in MDA-MB-468 cells in a dose-dependent manner （<italic>P</italic><0.05， <italic>P</italic><0.01）. Baicalein （10， 20 μmol·L^-1） significantly up-regulated p-YAP and p-LATS1 protein expressions in MDA-MB-231 cells in a dose-dependent manner （<italic>P</italic><0.01）. Conclusion:Baicalein can inhibit colony formation of triple negative breast cancer MDA-MB-468 and MDA-MB-231 cells by mediating the reduction of YAP entry into the nucleus.