[Effects of miR-144-3p on Proliferation, Cell Cycle and Apoptosis of K562 Cells].

OBJECTIVE: To investigate the effects of miR-144-3p on cell proliferation, cell cycle and apoptosis of blast phase chronic myelogenous leukemia (CML) K562 cells. METHODS: K562 cells were cultured in vitro and mimics negative control, hsa-miR-144-3p mimics, inhibitor negative control and miR-144-3p inhibitor were respectively transfected into K562 cells with transfection reagents. The cells were divided into five groups including blank control, mimics negative control, miR-144-3p mimics, inhibitor negative control and miR-144-3p inhibitor. After transfection, the cell proliferation activity was detected by CCK-8 assay. The cell cycle distribution and apoptosis were detected by flow cytometry. RESULTS: Compared with the blank control and mimics negative control groups, the proliferation rate of miR-144-3p mimics group was significantly decreased (P<0.05), the proportion of S phase cells was markedly increased (P<0.05), while the proportion of G1 phase cells was obviously decreased (P<0.05), and the apoptosis rate was significantly increased (P<0.05). Compared with the blank control and inhibitor negative control groups, the proliferation rate of miR-144-3p inhibitor group was obviously increased (P<0.05), the proportion of S phase cells was markedly decreased (P<0.05), while the proportion of G1 phase cells was obviously increased (P<0.05), and the apoptosis rate was significantly decreased (P<0.05). CONCLUSION: miR-144-3p can inhibit the proliferation and promote apoptosis of K562 cells, affect the cell cycle, and block K562 cells in S phase, which indicates that miR-144-3p is involved in the cell cycle activity of CML during blastic phase.

An effective and chemotherapy-free strategy of all-trans retinoic acid and arsenic trioxide for acute promyelocytic leukemia in all risk groups (APL15 trial).

The combination of all-trans retinoic acid (ATRA) and arsenic trioxide (ATO) has been demonstrated to have comparable effectiveness or better to ATRA and chemotherapy (CHT) in non-high-risk acute promyelocytic leukemia (APL). However, the efficacy of ATRA-ATO compared to ATRA-ATO plus CHT in high-risk APL remains unknown. Here we performed a randomized multi-center non-inferiority phase III study to compare the efficacy of ATRA-ATO and ATRA-ATO plus CHT in newly diagnosed all-risk APL to address this question. Patients were assigned to receive ATRA-ATO for induction, consolidation, and maintenance or ATRA-ATO plus CHT for induction followed by three cycles of consolidation therapy, and maintenance therapy with ATRA-ATO. In the non-CHT group, hydroxyurea was used to control leukocytosis. A total of 128 patients were treated. The complete remission rate was 97% in both groups. The 2-year disease-free, event-free survival rates in the non-CHT group and CHT group in all-risk patients were 98% vs 97%, and 95% vs 92%, respectively (P = 0.62 and P = 0.39, respectively). And they were 94% vs 87%, and 85% vs 78% in the high-risk patients (P = 0.52 and P = 0.44, respectively). This study demonstrated that ATRA-ATO had the same efficacy as the ATRA-ATO plus CHT in the treatment of patients with all-risk APL.

[Study on Herpes Zoster Reactivation Induced by Arsenic in Patients with Acute Promyelocytic Leukemia].

OBJECTIVE: To investigate herpes zoster reactivation induced by arsenic in patients with acute promyelocytic leukemia (APL). METHODS: The clinical data of 212 patients with APL treated in the Department of Hematology of the First Affiliated Hospital of Xi'an Jiaotong University from 2008 to 2019 were retrospectively analyzed to observe the activation of varicella zoster virus induced by arsenic. Kaplan-Meier analysis, chi-square test, and boxplot were used to analyze and describe the cumulative dose of arsenic and the time from the beginning of arsenic treatment to the occurrence of herpes zoster. RESULTS: Excluding early death cases and early automatic discharge cases, 17 cases developed herpes zoster reactivation in 175 patients with APL treated with arsenic, and the cumulative median dose of arsenic was 6.2(2-12) mg/kg. Precise risk of reactivation of herpes zoster with 10 months in APL patients treated by arsenic was 9.7%. CONCLUSION: Arsenic treatment can induce high reactivation rate of herpes zoster virus.

[A three dimensional finite element study on stress distribution in maxillary central incisor restored with fiber post].

OBJECTIVE: To study the stress changes of maxillary central incisor restored with or without fiber post using three dimensional finite element method, and analysis the role of fiber post in determining the stress distribution in dentin. METHODS: Three dimensional finite element models of maxillary central incisor with various remaining tooth structure were established by spiral CT, Mimics software and ANSYS software. Test samples were restored with all-ceramic crown and fiber post all-ceramic crown, respectively. The von Mises stress and maximal tensile stress of dentin were recorded. RESULTS: The stress level in dentin of maxillary central incisor restored with fiber post all-ceramic crown was smaller than that restored with all-ceramic crown, the stress distribution of both were similar. CONCLUSION: The apply of fiber post can reduce the stress level in dentin of maxillary central incisor and decrease the risk of tooth breakage, but not change the stress pattern.