RESUMEN
Acute lymphocytic leukemia (ALL) is a type of childhood leukemia with the highest incidence; T-acute lymphocytic leukemia (T-ALL) is far more difficult to treat than B-acute lymphocytic leukemia (B-ALL) and has a poor long-term prognosis. Therefore, there is an urgent requirement to develop effective drugs for the treatment of T-ALL. Hirsutanol A is a natural sesquiterpenoid compound. The aim of the present study was to evaluate the in vitro anticancer activity of hirsutanol A against T-acute lymphocytic leukemia Jurkat cells and investigate the mechanism of action. A Cell Counting Kit-8 assay demonstrated that hirsutanol A inhibited the viability of Jurkat cells in a dose- and time-dependent manner. In addition, hirsutanol A induced cell cycle arrest at the G2 phase as determined via flow cytometry. Furthermore, Hoechst staining, Annexin V-FITC/propidium iodide double staining, mitochondrial membrane potential detection using JC-1 and western blot analysis of apoptotic proteins indicated that the inhibitory effect of hirsutanol A on Jurkat cells was associated with the induction of apoptosis. Of note, hirsutanol A induced the expression of the tumor suppressor p53, whereas simultaneous treatment with pifithrin-α, an inhibitor of p53, significantly reduced Jurkat cell apoptosis induced by hirsutanol A. In summary, the present study suggested that hirsutanol A inhibited Jurkat cell viability through induction of cell cycle arrest and p53-dependent initiation of apoptosis, thus hirsutanol may serve as a promising compound for the treatment of T-ALL.
RESUMEN
The aim of the present study was to analyze whether the use of salidroside (SAL) could overcome dexamethasone (DEX) resistance in T-acute lymphocytic leukemia cells. The human T-ALL DEX-resistant cell line, CEM-C1 and the DEX-sensitive cell line, CEM-C7 were used in the current study. The proliferation inhibition rates in these cells, treated with SAL and DEX alone, and in combination were detected using a Cell Counting Kit-8 assay, while the morphological changes of the cells were observed using an inverted microscope. Reverse transcription-quantitative PCR was used to detect the mRNA expression levels of the c-Myc and LC3 genes, while flow cytometry was used to detect the cell cycle distribution and the rate of apoptosis. In addition, western blot analysis was used to detect the protein expression levels of c-Myc, BCL-2, Bax, cleaved PARP and LC3. and acridine orange staining was used to detect the changes in acidic autophagy vesicles. It was found that SAL could effectively inhibit cell proliferation and induce apoptosis in the CEM-C1 and CEM-C7 cells. In addition, SAL promoted the induction of autophagy. The protein expression levels of c-Myc in the CEM-C1 cells were significantly higher compared with that in the CEM-C7 cells. SAL downregulated the mRNA expression levels of the c-Myc gene and protein in a dose-dependent manner. This suggested that SAL could inhibit the proliferation of the CEM-C1 and CEM-C7 cells, induce apoptosis and autophagy and overcome DEX resistance in the CEM-C1 cells. The mechanism may be associated with the downregulation of c-Myc.
RESUMEN
OBJECTIVE: To analyze the expression levels of miR-145 in ALL children and their effects on the prognosis of ALL and to explore the mechanism of miR-145 in reversing the resistance of ALL cells to glucocorticoids. METHODS: A GEO database dataset was used to analyze the expression levels of miR-145 in ALL children. The association between miR-145 and childhood prognosis was analyzed by the TARGET database data. The expression levels of miR-145 in the glucocorticoid-resistant ALL cell line CEM-C1 were increased by lipofectamine 2000-mediated transfection. Cell proliferation inhibition experiments were performed to detect the effect of miR-145 on the response of CEM-C1 cell line to glucocorticoids. The expression levels of the apoptotic, autophagic and drug resistance-associated genes and proteins were detected by qPCR and western blot analysis. RESULTS: The expression levels of miR-145 were decreased in ALL patients (P < 0.001) and the prognosis of ALL in children with high miR-145 expression was significantly improved (P < 0.001). Increased miR-145 expression can improve the sensitivity of CEM-C1 cells to glucocorticoids. The expression levels of the proapoptotic and the anti-apoptotic genes Bax and Bcl-2 were increased and decreased, respectively, whereas the expression levels of the autophagicgenes Beclin 1 and LC were increased. In addition, the expression levels of the drug resistance gene MDR1 were decreased. CONCLUSION: The expression levels of miR-145 in ALL children were decreased and they were associated with disease prognosis. The data indicated that miR-145 can reverse cell resistance by regulating apoptosis of CEM-C1 cells and autophagy.
RESUMEN
The main physiological function of megakaryocytes is the production of platelets, whose development, maturation and platelet production are a complex regulatory process, and are involved in many factors. In recent years it was found that the lung is also the main site of megakaryocyte-producing platelets in addition to bone marrow. Based on the findings of recent years, this review summarizes the process of megakaryocyte development, maturation and platelet production, with emphasis on the analyzing the regulatory effects of apoptotic factors, miRNA, thrombopoietin and its receptors, interleukins, transcription factors and their corresponding signal pathways on platelet production. To understand the regulatory mechanism of platelet production can help to understand the pathological mechanism of platelet-related diseases and provide new ideas for the diagnosis and treatment of platelet-related diseases.