[Inhibitory Effect of Metformin and Arsenic Trioxide on KG1a Cell Proliferation].

OBJECTIVE: To investigate the effect of metformin and arsenic trioxide on KG1a cells proliferation of acute myeloid leukemia and its possible mechanism. METHODS: CCK-8 method was used to detect the killing effect of metformin, arsenic trioxide and combined application on KG1a cells. Annexin V-FITC/PI Dual Stain Flow Cytometry was used to detect the effect of combined application on apoptosis of KG1a cells. Western blot was used to detect the expression of intracellular apoptosis-,autophagy-related protein. RESULTS: Metformin and arsenic trioxide alone or in combination could inhibit the proliferation of KG1a cells and induce apoptosis of KG1a cells, and the proliferation inhibition rate and apoptosis rate in the combined drug group were higher than those in the drug group alone(P <0.05). The combination of drugs induced upregulation of Caspase 8 protein and P62 protein expression and was higher than that in the drug group alone(P <0.05). CONCLUSION: Metformin can synergize with arsenic trioxide to kill KG1a cells, and its mechanism of action may be related to inducing apoptosis and enhancing autophagy.

Effects of Spermidine on Mouse Gut Morphology, Metabolites, and Microbial Diversity.

Spermidine is a class of biologically active organic small molecules that play an important role in maintaining intestinal homeostasis. The specific objective of this study was to explore the effects of spermidine on intestinal morphology, metabolites, and microbial diversity in mice. We showed that 0.3 mmol/L of spermidine significantly promoted the growth of ileal villi (p < 0.05), and 3.0 mmol/L of spermidine significantly increased the body weight of mice and promoted the growth of jejunum villi (p < 0.05). The 16S rDNA sequencing results indicated that 3.0 mmol/L of spermidine affected the balance of the intestinal flora by increasing the abundance of intestinal Lactic acid bacteria and reducing the abundance of harmful bacteria (Turicibacter and Alistipes). Additionally, spermidine affects the levels of microbial metabolites such as succinic acid and Pantetheine. In summary, spermidine affects intestinal morphology and regulates intestinal flora and metabolites, and this study has provided a new understanding of spermidine's effects on the intestinal tract.

[Effect of DR4 Demethylation to the Proliferation and Apoptosis of Myeloid Leukemia K562 Cells].

OBJECTIVE: To investigate the effect of tumor necrosis factor death receptor (DR) 4 demethylation to the proliferation and apoptosis of myeloid leukemia K562 cells. METHODS: The logarithmic phase of K562 cells were treated by desitabine (DCA) at 0, 0.8, 1.6 and 3.2 µmol/L, and the cells were divided into control group, DCA low dose group, DCA medium dose group and DCA high dose group respectively. The cells in control group were treated by tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) 0.5 µg/ml for 24 h, and the cells were divided into TRAIL group. The cells in DCA high dose group were treated by TRAIL 0.5 µg/ml for 24 h, and were divided into DCA high dose + TRAIL group. Methylation-specific polymerase chain reaction (MS-PCR) was used to measure the methylation status of the DR4 gene promoter in the control group and DCA low, medium and high dose groups. Real-time fluorescent quantitative polymerase chain reaction (qRT-PCR) and Western blot were used to determine the relative expression of DR4 mRNA and protein in the control group and DCA low, medium and high dose groups. Dime- thylthiazole (MTT) method was used to determine the inhibition rate of cell proliferation of the cells in control group, DCA high dose group, TRAIL group, DCA high dose + TRAIL group. Flow cytometry was used to determine the apoptotic rate of the cells in control group, DCA high dose group, TRAIL group, DCA high dose + TRAIL group. RESULTS: The cells in the control group were methylation-positive, the brightness of the methylation bands of the cells in the DCA low, medium, and high dose groups was gradually decreased to disappear, and the DCA high dose group showed negative for methylation. The relative expression of DR4 mRNA and protein in the control group, DCA low, medium and high dose groups was increased sequentially (r=0.624, 0.704). The inhibition rate of cell proliferation of the cells in the control group, DCA high dose group, TRAIL group, DCA high dose + TRAIL group was increased sequentially (r=0.653, 0.754, 0.709, 0.725) at 24, 48 and 72 h. CONCLUSION: DCA can reverse the methylation level of DR4 gene promoter in ML K562 cells and up-regulate the expression of DR4, which may enhance the proliferation inhibition and apoptosis promotion effects of TRAIL on K562 cells.

[Anti-mouse CD122 antibody promotes the hematopoietic repopulating capacity of cord blood CD34⁺ cells in NOD/SCID mice].

The study was aimed to investigate the effect of anti-mouse CD122 antibody on the hematopoietic repopulating capacity of cord blood CD34⁺ cells in a humanized murine model-non obese diabetic/severe combined immunodeficiency (NOD/SCID) mice. After sublethal irradiation with γ-ray, NOD/SCID mice were intraperitoneally injected with 200 µg mouse isotype control antibody or anti-mouse CD122 antibody. Human cord blood CD34⁺ cells or phosphate-buffered saline (PBS) were injected via the tail vein at 6-8 hours later. Cohort of the mice injected with anti-mice CD122 antibody or control antibody alone were sacrificed at different time point (at week 2, 3, and 4 weeks) after the injection, and the percentage of NK cells in the peripheral blood was analyzed by flow cytometry. To evaluate the effect of anti-mouse CD122 antibody on the repopulating capacity of cord blood CD34⁺ cells in the recipient mice, phenotype analysis was performed in the bone marrow at 6 and 8 weeks after the transplantation. The results showed that the proportion of NK cells in the peripheral blood were (4.6 ± 0.6)% and (5.7 ± 1.7)% at week 2 and 3 after anti-CD122 antibody injection respectively,which decreased by 60%, compared with the mice injected with isotype control antibody. After 6 and 8 weeks of cord blood CD34⁺ cell transplantation,the percentage of human CD45⁺ in the bone marrow of the recipient mice treated with anti-mice CD122 antibody was (63.0 ± 12.2)% and (53.2 ± 16.3)%,respectively,which were dramatically higher than that in the mice treated with isotype control antibody (7.7 ± 3.6)% and (6.1 ± 2.4)%. Moreover,at 8 weeks after transplantation,human CD34⁺ cells appeared significantly in the recipients treated with anti-CD122 antibody. It is concluded that the anti-mouse CD122 antibody enhances the hematopoietic repopulating capacity of cord blood CD34⁺ cells in the NOD/SCID mice through decreasing the proportion of NK cells.

The diagnostic and prognostic value of serum YKL-40 in endometrial cancer.

PURPOSE: To evaluate the diagnostic and prognostic value of serum YKL-40 in endometrial cancer (EC). METHODS: Serum YKL-40 levels were detected and compared in 34 of the 50 cases with EC before surgery, in 22 of the 34 with EC after surgery, in 30 cases with uterine myoma, and in 30 healthy women as normal controls. Receiver operating characteristics (ROC) curves were adopted for diagnosis and calculation of area under each ROC curve in EC. The progression-free survival (PFS) and overall survival (OS) between YKL-40 positive and negative patients were compared in the follow-up. RESULTS: The mean pre-operative serum YKL-40 values were significantly higher than that in the uterine myoma cases and in the healthy women (P = 0.000). The mean post-operative serum YKL-40 in the 22 EC cases was significantly lower than pre-operative serum YKL-40 levels in these cases (P = 0.000). There were critical differences between the area under ROC curve for YKL-40 and CA125 (P = 0.053). The PFS and OS for the YKL-40-positive patients were significantly shorter than those for the YKL-40-negative patients. CONCLUSION: Preliminary investigations have shown that serum YKL-40 level may have a definite clinical value in the diagnosis and prognosis of EC.

Expression of HLA-I, CD8, and CD4 and Their Clinical Significance in Cervical Cancer.

BACKGROUND: The local tissue immune status may play a role in the progression of cervical cancer. The aim of our study is to examine the expression of HLA-I, CD8 and CD4 in various cervical diseases and investigate their association with cervical cancer. METHODS: We chose the tissues of cervical cancer, cervical intraepithelial neoplasia (CIN), chronic cervicitis and peri-cancer tissues, and then detected the expression of HLA-I, CD8 and CD4 using SP immunohistochemistry. The associations of the expression of HLA-I, CD8 and CD4 with the clinicopathologic profiles of the patients were analyzed. RESULTS: The percentage of positive tissue staining of HLA class I antigen in cervical cancer, CIN, chronic cervicitis and peri-cancer tissues were 40%, 95%, 100.0% and 100.0%, respectively. And the percentage of CD8 in various tissues was 35%, 95%, 100% and 100.0%, respectively. The positive tissue staining percentage of CD4 in the tissues above was 45%, 80%, 100% and 100%, respectively. The percentage of positive tissue staining of HLA-I, CD8 and CD4 were significantly lower in tissues of cervical cancer when compared with other tissues (P < 0.01). No correlation between positive tissue staining of HLA-I, CD8, and CD4 and clinicopathologic profiles was observed (P > 0.05). A positive correlation was found between HLA-I and CD8 expression (Spearman's correlation rs = 0.913, P < 0.001). CONCLUSIONS: The expression of HLA-I, CD8 and CD4 are down-regulated or deleted in CIN and cervical cancer, and they may play important roles in the development and progression of CIN and cervical cancer.

[Effects of transforming growth factor and recombinant human bone morphogenetic protein 2 on the proliferation and differentiation of human periodontal ligament fibroblasts].

OBJECTIVE: To investigate the effects of Transforming growth factor beta (TGFbeta) and recombinant human bone morphogenetic protein 2 (rhBMP2) on the proliferation and differentiation of human periodontal ligament fibroblasts (HPDLFs). METHODS: To observe the individual, simultaneous and sequential effects of TGFbeta and rhBMP2 on the proliferation, alkaline phosphatase (ALP) activity, osteocalcin (OC) synthesis and mineralized nodule formation of the cultured HPDLFs. RESULTS: TGFbeta significantly stimulated the proliferation of HPDLFs but had no effects on ALP activity, OC synthesis and mineralized nodule formation. RhBMP2 had no remarkable effect on the proliferation of HPDLFs, whereas significantly stimulated the ALP activity, OC synthesis and mineralized nodule formation. Co-treatment with TGFbeta and rhBMP2 led to intermediate effects on cell proliferation and differentiation. Pre-treatment with TGFbeta did not influence the subsequent rhBMP2 action on HPDLFs differentiation. Pre-treatment with rhBMP2 and subsequent with TGFbeta had a remarkable stimulation on HPDLFs differentiation. CONCLUSION: RhBMP2 can stimulate the expression of osteoblastic phenotype of HPDLFs. TGFbeta significantly stimulated the rhBMP2 effects on the differentiation of HPDLFs. TGFbeta and BMP2 may act at different stages to promote HPDLFs differentiation towards the osteoblast phenotype.