Rapamycin for treatment of tyrosine kinase inhibitor-resistant chronic myelogenous leukemia: report of two cases and review of literature / 白血病·淋巴瘤

ABSTRACT

Objective:To investigate the effect of rapamycin in treatment of tyrosine kinase inhibitor (TKI)-resistant chronic myelogenous leukemia (CML) without ABL mutation.Methods:Flow cytometry was used to detect the positive expressions of p-mTOR and p-S6 in CD33 positive cells of 2 CML patients with TKI resistance in Jiangsu Province Hospital, and the influence of rapamycin on the positive expressions of p-mTOR and p-S6 in vitro.Results:Rapamycin in vitro inhibited the positive expressions of p-mTOR and p-S6 in CD33 positive cells. After 3 months of oral administration of rapamycin, the positive expressions of p-mTOR and p-S6 in CD33 positive cells were decreased, and the copy number of BCR-ABL fusion gene was also decreased simultaneously.Conclusion:Part of the resistance of CML patients to TKI may be related to the activation of intracellular signaling pathway of mTOR.