The role of CSE1L silencing in the regulation of proliferation and apoptosis via the AMPK/mTOR signaling pathway in chronic myeloid leukemia.

OBJECTIVES: Chromosome segregation 1-like (CSE1L) is abundant and strongly expressed in solid tumors. However, the expression and role of CSE1L in chronic myeloid leukemia(CML) remain largely unknown. MATERIALS AND METHODS: The relative expression levels of CSE1L in bone marrow granulocytes from patients with primary CML and non-hematologic controls were measured by flow cytometry. Cell counting kit-8 analysis, DNA Content Quantitation Assay, and Annexin V-PE/7-AAD staining were applied to assess the effects of CSE1L knockdown on cell proliferation, cell cycle progression, and apoptosis. RESULTS: Elevated expression of CSE1L was detected in bone marrow granulocytes of patients with primary CML. In the CML cell line K562 cells, CSE1L knockdown impaired cell proliferation blocked the cell cycle shift from G0/G1 phase to the S phase, and promoted apoptosis. Knockdown of CSE1L reduced Bcl-2 protein expression and increased Bax protein expression. Meanwhile, knockdown of CSE1L enhanced the expression of phospho-AMPK protein and decreased the expression of phospho-mTOR protein. The expression of total AMPK and mTOR proteins was not affected. In addition, CSE1L expression levels were decreased in imatinib-treated K562 cells. CONCLUSIONS: CSE1L plays a pivotal role in K562 cell survival and growth. These functions may be partially dependent on the AMPK/mTOR signaling pathway to achieve. In addition, CSE1L may have had a future impact on the treatment of CML patients.

[Expression and Clinical Significance of CAS in Acute Myeloid Leukemia Patients].

OBJECTIVE: To explore the expression of cellular apoptosis susceptibility protein （CAS） in acute myeloid leukemia （AML） and its correlation with clinical characteristics. METHODS: The expression of CAS in bone marrow tissue of 54 patients with AML and 24 patients with non-hematological malignant diseases was detected by Western blot and immune-histochemical method, and compared between AML group and control group. Also the relationship of CAS expression in AML and sex, age, WBC count, Hb, platelet count, bone marrow blast cell ratio, ki-67 index, cytogenetic and molecular biological prognostic risk stratification, extramedullary infiltration and other clinical characteristics was analyzed. RESULTS: Western blot showed that the expression of CAS protein in bone marrow biopsies of AML patients was significantly higher than that in control group (P<0.05). Immune-histochemical method revealed that CAS was mainly located in the cytoplasm in both AML group and control group. Among 54 AML patients, 14 patients (25.9%) showed high expression of CAS, while all the 24 patients in the control group showed low expression of CAS. The high expression rate of CAS in AML patients was significantly higher than that in the control group (P<0.05). There were statistically significant differences in prognostic risk stratification and the remission rate of the first chemotherapy between CAS high expression group and CAS low expression group in AML (P<0.05). The proportion of high risk patients and unremission patients after the first chemotherapy in CAS high expression group were significantly higher than those in CAS low expression group (57.1% vs 27.5%, 30.8% vs 7.9%), while the proportion of low risk patients and complete remission patients after the first chemotherapy were significantly lower than those in CAS low expression group (14.3% vs 37.5%, 53.8% vs 84.2%). In AML patients, the ki-67 index of bone marrow tissue in CAS high expression group was higher than that in CAS low expression group (60% vs 50%) (P<0.05). CONCLUSION: CAS is localized in cytoplasm in both AML and non-hematological malignant diseases, and its expression increases in AML. CAS is related to the risk stratification of cytogenetics and molecular biology, the remission rate after the first chemotherapy and ki-67 index in AML, which suggests that CAS may be involved in the occurrence and development of AML.

Predictive Value of Small Dense Low-Density Lipoprotein in Coronary Heart Disease in the Chinese Population.

BACKGROUND: Coronary heart disease (CHD) is a global public health concern, and CHD risk assessment remains a major challenge. Therefore, in this study, the ability of small dense low-density lipoprotein (sdLDL) alone to sufficiently predict CHD risk in the Chinese population was evaluated. METHODS: Patients with CHD (139) and healthy controls (58) were included in this study. Serum sdLDL was measured using the peroxidase method. Other lipid parameters were also determined. RESULTS: The sdLDL level in the CHD group was significantly higher than that in the control group (p < 0.001). Logistic regression analysis revealed that sdLDL was an independent risk factor for CHD. Based on the receiver operating characteristic curves, the area under the curve (AUC) of sdLDL alone for CHD was 0.722. The AUC of triglycerides (TG), high-density lipoprotein (HDL), and sdLDL combined was 0.763, which was larger than that of the independent ones or combinations of any two; however, the value was not significant. CONCLUSIONS: sdLDL alone can predict CHD risk efficiently similar to the combination of TG, HDL, and sdLDL. This finding suggests that sdLDL can be considered as an ideal parameter for the preliminary diagnosis of CHD in Chinese people.

[Cloning of PD-1 gene and its prokaryotic expression in Escherichia coli].

OBJECTIVE: To clone human PD-1 gene, construct a prokaryotic expression plasmid and express in E. coli. METHODS: The human PD-1 cDNA was cloned by RT-PCR from the total RNA, which was extracted from peripheral blood lymphocyte cell of the patient with chronic hepatitis B. Recombinant PD-1 protein was been expressed and purified after the prokaryotic expression plasmid had been constructed. It was identified by SDS-PAGE, DNA sequencing and amino acid sequencing. RESULTS: The PD-1 gene was cloned and confirmed by DNA sequencing. The recombinant protein was expressed in E. coli. The purified protein was obtained, then been confirmed by amino acid sequencing. CONCLUSION: The human PD-1 gene was successfully cloned and expressed in E. coli, which lays the foundation for further study on the function and application of PD-1.

High density fermentation and activity of a recombinant lumbrokinase (PI239) from Pichia pastoris.

A system for the expression of recombinant lumbrokinase (rPI239) was developed in the yeast Pichia pastoris. A total supernatant protein content of 0.174 g/L of high density fermentation broth was obtained. The rPI239 exhibited in vitro fibrinolytic activity. The in vivo activity of rPI239 was measured by prothrombin time, kaolin part thrombin time, thrombin time, and fibrinolytic activity. This work presents the high-density fermentation of rPI239 from P. pastoris and shows that the recombinant protein has similar fibrinolytic activity both in vivo and in vitro.