CK2 Inhibitors And Hsp90 Inhibitors Against HER2-overexpressing Breast Cancer Cells,synergy And Mechanism Research

Objective:Ganetespib and CX-4945 joint for HER2-overexpressing breast cancer cells-SKBR3、MDA-MB-453 have good synergy.And to study the mechanism of the combination Ganetespib with CX-4945.Methods:(1)MTT assay was used for cell proliferation determination in vitro by Ganetespib and CX-4945 in HER2-overexpressing breast cancer cells SKBR3、MDA-MB-453.(2)The CI values between Ganetespib and CX-4945 in HER2-overexpressing breast cancer cells SKBR3、MDA-MB-453 was evaluated by using the Compu Syn Software.(3)Western blot was used to detect the influence of different concentrations of Ganetespib 、 CX-4945 and the combination Ganetespib with CX-4945 in PI3K/AKT and Raf/Mek/ERK1/2 pathway related protein level.(4)Cell colony was used to observe the different influence of Ganetespib、CX – 4945 and the combination Ganetespib with CX-4945 in HER2-overexpressing breast cancer cells SKBR3、MDA-MB-453.(5)Through FITC/PI double staining detected the apoptotic effect of Ganetespib、CX-4945 and the combination Ganetespib with CX-4945 on SKBR3、MDA-MB-453 cells.(6)The study of the possible synergistic mechanism between Ganetespib and CX-4945 in HER2-overexpressing breast cancer cells was evaluated by using the Co-Immunoprecipitation.Results:(1)By MTT experiments we found that Ganetespib which is HSP90 inhibitor and CX – 4945 which is CK2 inhibit dose-dependently proliferation in HER2-overexpressing breast cancer cells-SKBR3 、 MDA-MB-453.(2)Through Com Pusyn software we found that Ganetespib and CX-4945 joint for HER2-overexpressing breast cancer cells have good synergy(CI < 1),could significantly inhibit the proliferation of SKBR3 and MDA-MB – 453.(3)By protein imprinting experiments we found that Ganetespib and CX-4945 joint can blockPI3K/AKT and Ras-Raf-MAPK signaling pathways related proteins,and blocking effect is better than alone.So the combination has the synergistic inhibition signaling pathways related protein expression.(4)Through the colony forming experiment we found that Ganetespib and CX-4945 joint have obvious inhibitory effect on the colony forming,and the combined effect is better than single medicine.(5)By FITC/PI staining we found that Ganetespib and CX-4945 joint can enhance HER2-overexpressing breast cancer cells apoptosis,and the effect is better than single medicine.(6)By immune coprecipitation we found CX – 4945,which is under the same amount of HSP90 can reduce the expression of CDC37.So Ganetespib joint CX-4945 significantly inhibited the expression of HER2.Conclusion: Ganetespib and CX-4945 all have good antitumor effect in vitro.Then Ganetespib and CX-4945 alone can block PI3K/AKT and Ras-Raf-MAPK cell proliferation pathway,which combined use of stronger.CX-4945 and Ganetespib together promote positive HER2 breast cancer cells apoptosis.Because CX-4945 can inhibit CDC37 which results in inhibit the activity of HSP90,so as to achieve the role of collaborative Ganetespib,increase Ganetespib targeting and reduce possible adverse reactions.Therefore Ganetespib and CX-4945 joint for HER2 positive breast cancer patients to provide new theoretical basis and train of thoughts.