Effects of circ-SFMBT2 on Proliferation, Migration and Invasion of Acute Myeloid Leukemia Cells by Regulating miR-491-5p/HOXA9 Axis / 中国实验血液学杂志

OBJECTIVE@#To explore the effects and molecular mechanism of circ-SFMBT2 on the proliferation, migration and invasion of acute myeloid leukemia (AML) cells.@*METHODS@#Bone marrow samples from 35 pediatric AML patients and 35 healthy controls in Henan Provincial Children's Hospital from April 2015 to April 2017 and human bone marrow stromal cell lines (HS-5) and AML cell lines (HL-60, THP-1, U-937 and Kasumi-1) were collected. The expressions of circ-SFMBT2, miR-491-5p and homeobox A9 (HOXA9) in bone marrow samples and cells were detected by RT-qPCR and Western blot. The Pearson method was used to analyze the correlation of circ-SFMBT2, miR-491-5p and HOXA9 mRNA expression levels in bone marrow samples of AML patients. HL-60 cells were cultured in vitro and divided into 5 groups: Control, si-NC, si-circ-SFMBT2, si-circ-SFMBT2+anti-NC and si-circ-SFMBT2+anti-miR-491-5p, HL-60 cells were transfected with si-NC, si-circ-SFMBT2, anti-NC, and miR-491-5p inhibitor with Lipofectamine™ 3000. RT-qPCR and Western blot were performed to detect the expression levels of circ-SFMBT2, miR-491-5p and HOXA9 in cells of each group. The proliferation activity of HL-60 cells in each group was detected by CCK-8 assay at 24, 48 and 72 h after transfection, respectively. The apoptosis rate was detected by flow cytometry. The migration and invasion abilities of cells were detected by Transwell assay. The regulatory roles of circ-SFMBT2, miR-491-5p and HOXA9 in AML cells were verified by dual-luciferase reporter gene assay, RNA pull-down and RNA-binding protein immunoprecipitation (RIP) experiments.@*RESULTS@#The expression levels of circ-SFMBT2 and HOXA9 mRNA were increased in bone marrow samples and cell lines (HL-60, THP-1, U-937 and Kasumi-1) of children with AML (P <0.001), while the expression level of miR-491-5p was significantly decreased (P <0.001). Pearson correlation analysis showed that the expression levels of circ-SFMBT2 and miR-491-5p in bone marrow samples of AML children were negatively correlated (r =-0.905), miR-491-5p was also negatively correlated with HOXA9 mRNA (r =-0.930), while the expression levels of HOXA9 mRNA and circ-SFMBT2 was positively correlated (r =0.911). The overall survival rate of AML children with high expression of circ-SFMBT2 was significantly decreased than those with low expression of circ-SFMBT2 (P <0.05). Silencing of circ-SFMBT2 could greatly up-regulate the expression of miR-491-5p, decrease the expression of HOXA9, inhibit the proliferation, migration and invasion of AML cells, and promote cell apoptosis (P <0.05). Down-regulation of miR-491-5p expression greatly attenuated the inhibitory effects of circ-SFMBT2 silencing on cell proliferation, migration and invasion (P <0.05). Dual-luciferase reporter gene assay, RNA pull-down and RIP experiments confirmed that circ-SFMBT2 could target miR-491-5p and negatively regulate the expression of miR-491-5p in AML, and HOXA9 was the target of miR-491-5p.@*CONCLUSION@#Silencing of circ-SFMBT2 may inhibit the proliferation, migration and invasion of AML cells by regulating the miR-491-5p/HOXA9 axis.

Effect of breastfeeding on immune function in infants with human cytomegalovirus infection / 中国当代儿科杂志

OBJECTIVES@#To study the effect of breastfeeding on immune function in infants with human cytomegalovirus (HCMV) infection.@*METHODS@#A retrospective analysis was performed on the medical data of 135 infants with HCMV infection who were admitted to Children's Hospital Affiliated to Zhengzhou University from January 2021 to May 2022, and all these infants received breastfeeding. According to the results of breast milk HCMV-DNA testing, the infants were divided into two groups: breast milk HCMV positive (n=78) and breast milk HCMV negative (n=57). According to the median breast milk HCMV-DNA load, the infants in the breast milk HCMV positive group were further divided into two subgroups: high viral load and low viral load (n=39 each). Related indicators were compared between the breast milk positive and negative HCMV groups and between the breast milk high viral load and low viral load subgroups, including the percentages of peripheral blood lymphocyte subsets (CD3+ T cells, CD3+CD4+ T cells, CD3+CD8+ T cells, and CD19+ B cells), CD4+/CD8+ ratio, IgG, IgM, IgA, and urine HCMV-DNA load.@*RESULTS@#There were no significant differences in the percentages of CD3+ T cells, CD3+CD4+ T cells, CD3+CD8+ T cells, and CD19+ B cells, CD4+/CD8+ ratio, IgG, IgM, IgA, and urine HCMV-DNA load between the breast milk HCMV positive and HCMV negative groups, as well as between the breast milk high viral load and low viral load subgroups (P>0.05).@*CONCLUSIONS@#Breastfeeding with HCMV does not affect the immune function of infants with HCMV infection.