Study On The Role And Mechanism Of The Second Generation HSP90 Inhibitor(Ganetespib)in The Treatment Of Mantle Cell Lymphoma

OBJECTIVE: To study the role and mechanism of the second generation HSP90(Ganetespib)targeting therapy for mantel cell lymphoma(MCL),and to provide experiments for the treatment of MCL patients with Ganetespib.HSP90 was inhibited by small molecule inhibitors,and laid the foundation for the study of the signal regulation of the mechanism of MCL.METHODS: First,we studied effects of Ganetespib on the proliferation of two common MCL cell lines,Jeko-1 and Granta-519,and lymphocytes TZG-1 isolated from normal human peripheral blood.Then,the cell cycle of Jeko-1 and Granta-519 cells after Ganetespib pretreatment was analyzed by flow cytometry.And then,we analyzed the changes of apoptosis of the MCL cell line Jeko-1 by Ganetespib pretreatment.In addition,we also used STRING software to analyze proteins that were closely related to HSP90.The protein with the correlation coefficient of 0.4 or higher was selected as the further study object.The mRNA primers corresponding to these protein genes were designed and the mRNA level was detected by qRT-PCR.ERBB2,MYC,EGFR,AKT1 and BCL2 were detected by western blot after the pretreatment of Ganetespib,and the mRNA of the gene encoding the protein was down-regulated.In addition,Ganetespib was also administered to immunodeficient Nu/Nu mice subcutaneously inoculated with Jeko-1 cells.When the tumor tissue was removed,immunohistochemical staining was used to determine the apoptosis of tumor cells and the changes of some carcinogenic proteins.Finally,we collected lymphocytes from several different lymphoma patients from the hospital,and studyed Ganetespib to inhibit the proliferation of these cells and some changes in tumorigenic protein content.RESULTS: In vitro experiments,Ganetespib could inhibit the proliferation of Jeko-1 and Granta-519,and a little effect on TUZ-1 cells.Ganetespib can promote the arrest of G2 / M phase of Jeko-1 and Granta-519 cells and inhibit cell proliferation.Ganetespib induced apoptosis in Jeko-1 cells in a dose-dependent manner.The expression of ERBB2,MYC,EGFR,AKT1 and BCL2 were up-regulated by Jeko-1 cells pretreated with Ganetespib,and the tumor suppressor protein CDH1 was up-regulated.In vivo experiment,Ganetespib was able to effectively inhibit tumor growth in mice with lateral translocation of Jeko-1 cells and promote apoptosis of tumor cells.The expression of two oncogene(cyclin D1 and c-Myc)in tumor tissue was also significantly decreased.Clinically,Ganetespib can also effectively inhibit lymphoma proliferation isolatedFrom different lymphoma patients,c-Myc and c-Jun two protein levels were significantly reduced.CONCLUSION: Ganetespib can effectively inhibit the proliferation of MCL cell line and promote the apoptosis of MCL cell line.When HSP90 function was inhibited,the tumor suppressor protein were up-regulated and tumorigenic protein were down-regulated.Ganetespib can also inhibit the growth of mouse tumors subcutaneously in MCL cell lines and inhibit lymphocyte proliferation in clinically isolated lymphoma patients.