Effect of azacitidine on HOXA9 gene expression and biological behaviors of A375 melanoma cells / 中华皮肤科杂志

Objective:To investigate the effect of the methyltransferase inhibitor azacitidine (5-azaC) on the expression of homeobox A9 (HOXA9) gene in, as well as proliferation, invasion and migration of A375 cells.Methods:In vitro cultured A375 cells were treated with 5-azaC at various concentrations of 1, 5, 10 and 20 μmol/L, while routinely cultured A375 cells receiving no drug intervention served as control group. Methylation-specific PCR was performed to analyze methylation status of the HOXA9 gene promoter region after the treatment with different concentrations of 5-azaC, in order to screen the optimal concentration of 5-azaC for following experiments. Cell counting kit-8 (CCK8) assay was conducted to evaluate the proliferation of A375 cells, Transwell and wound healing assays were performed to estimate the invasion and migration of A375 cells, and real-time fluorescence-based quantitative PCR (qRT-PCR) and Western blot analysis were conducted to determine the mRNA and protein expression of HOXA9 in A375 cells after 5-azaC treatment. Two-independent-sample t test was used for comparisons between two groups. Results:Methylation was observed in the HOXA9 gene promoter region in A375 cells in the control group. After 5-azaC treatment, methylated and unmethylated states coexisted in the HOXA9 gene promoter region in A375 cells, and the higher the concentration of 5-azaC, the higher the degree of demethylation of the HOXA9 gene. Therefore, 20 μmol/L 5-azaC was selected to treat A375 cells for 72 hours, which served as 5-azaC treatment group in subsequent experiments. Compared with the control group, the 5-azaC treatment group showed significantly decreased cellular proliferative ability (72.46% ± 2.19% vs. 100%, t = 28.09, P < 0.001) , significantly decreased number of invasive cells (242.70 ± 29.19 vs. 466.00 ± 22.65, t = 10.47, P < 0.001) , significantly decreased migratory ability (27.56% ± 2.74% vs. 35.69% ± 2.50%, t = 3.79, P = 0.019) , significantly increased HOXA9 mRNA expression (1.73 ± 0.28 vs. 1.01 ± 0.15, t = 3.93, P = 0.017) , and significantly increased HOXA9 protein expression (0.62 ± 0.03 vs. 0.50 ± 0.01, t = 3.82, P = 0.019) . Conclusion:5-azaC can inhibit the proliferative, invasive and migratory ability of A375 melanoma cells, and one of the possible mechanisms underlying this process may be that 5-azaC reverses the methylation in the HOXA9 gene promoter region, activates HOXA9 gene expression, and participates in the regulation of biological behaviors of melanoma cells.

Unfractionated heparin inhibits the activation of endothelial cells by decreasing the degree of HOXA9 reduced expression / 中华危重病急救医学

Objective To study unfractionated heparin (UFH) effect on the expression of HOXA9 in activation of human umbilical vein endothelial cells (HUVECs) induced by lipopolysaccharide (LPS). Methods HUVECs were cultured and they were randomly divided into four groups (n = 5) for the challenge respectively: ① control group (with an equal volume of phosphate buffer saline); ② LPS group (LPS 10 mg/L); ③UFH group (UFH 10 kU/L);④ UFH+LPS group (10 kU/L UFH 30 minutes + LPS 10 mg/L). After treatment for 3 hours, the expressions of HOXA9, E-selectin and nuclear factor-κB (NK-κB) in endothelial cells were detected by Western Blot. Results Compared with the control group, the expression of HOXA9 in LPS group was significantly decreased, the expressions of E-selectin and NF-κB were significantly increased (HOXA9/β-actin: 0.082±0.009 vs. 0.199±0.067, E-selectin/β-actin:0.113±0.055 vs. 0.047±0.030, NF-κB/β-actin: 0.845±0.025 vs. 0.664±0.092, all P < 0.05). Compared with LPS group, the expression of HOXA9 in UFH+LPS group was significantly increased, the expressions of E-selectin and NF-κB were significantly decreased (HOXA9/β-actin: 0.190±0.096 vs. 0.082±0.009, E-selecin/β-actin: 0.057±0.017 vs. 0.113±0.055, NF-κB/β-actin: 0.544±0.060 vs. 0.845±0.025, all P < 0.05). Each protein expression of UFH group were in accordance with the control group. Conclusions In LPS stimulated endothelial cells, HOXA9 expression is down regulated, E-expression is reduced, and endothelial cell activation is inhibited. UFH can inhibit the activation of endothelial cells by decreasing the degree of HOXA9 reduced expression.

HOXA9 Gene Expression and Cytogenetic Analysis in Egyptian Acute Myeloid Leukemia Patients.

Aim: we investigatedthe frequency of expression of HOXA9 gene in adult Egyptian acute myeloid leukemia (AML) patients and its relation to different cytogenetic abnormalities. Methods: 30 newly diagnosed AML patients (group 1) were the subject of our study. Ten healthy persons of matched age and sex were considered group ll (controls). Estimation of HOXA9 expression in AML blasts by RT-PCR was done to both groups. Results: Normal cytogenetic analysis was present in 20 cases (66.6%), t(15,17) in 3 cases, t(8,21) in 3 cases, 45 xy -7 in 1 case, t(16,16) in 1 case, 45 xy-20 in 1 case and 46 XX 1P+ in 1 case. NUP 98 -HOXA 9 gene was not detected in any of the studied case or in the control group. Conclusion: absence of HOXA9 gene in our randomly selected patientsmay be related to its rarity in Egyptian population. However, further studies including larger population is still needed to confirm this finding with special stress on poor cytogenetic group.

Elucidation of the Molecular Interaction between miRNAs and the HOXA9 Gene, Involved in Acute Myeloid Leukemia, by the Assistance of Argonaute Protein through a Computational Approach

Acute myeloid leukemia is a well characterized blood cancer in which the unnatural growth of immature white blood cell takes place, where several genes transcription is regulated by the micro RNAs (miRNAs). Argonaute (AGO) protein is a protein family that binds to the miRNAs and mRNA complex where a strong binding affinity is crucial for its RNA silencing function. By understanding pattern recognition between the miRNAs-mRNA complex and its binding affinity with AGO protein, one can decipher the regulation of a particular gene and develop suitable siRNA for the same in disease condition. In the current work, HOXA9 gene has been selected from literature, whose deregulation is well-established in acute myeloid leukemia. Four miRNAs (mir-145, mir-126, let-7a, and mir-196b) have been selected to target mRNA of HOXA9 (NCBI accession No. NM_152739.3). The binding interaction between mRNAs and mRNA of HOXA9 gene was studied computationally. From result, it was observed mir-145 has highest affinity for HOXA9 gene. Furthermore, the interaction between miRNAs-mRNA duplex of all chosen miRNAs are docked with AGO protein (PDB ID: 3F73, chain A) to study their interaction at molecular level through an in silico approach. The residual interaction and hydrogen bonding are inspected in Discovery Studio 3.5 suites. The current investigation throws light on understanding of AGO-assisted miRNA based gene silencing mechanism in HOXA9 gene associated in acute myeloid leukemia computationally.

Progress in relationship between HOXA9 gene and leukemia / 国际儿科学杂志

HOXA9 is a member of homeobox gene,and more commonly expressed in leukemia cells,which may be involved in the development and progress of leukemia with Meisl, PBX1 and Trib2. HOXA9 also affects the treatment outcome and prognosis of leukemia, the higher the expression level, the poorer response to treatment, the prognosis is also poor.