Effect of MXRA7 on the Biological Functions of Acute B Lymphoblastic Leukemia Cell Line REH / 中国实验血液学杂志

OBJECTIVE@#To discover the relationship between matrix remodeling associated 7 (MXRA7) and acute B lymphoblastic leukemia (B-ALL), and explore the effect of MXRA7 on the biological functions of B-ALL cell line REH.@*METHODS@#The expression of MXRA7 in blood diseases was searched and analyzed through BloodSpot database. Real-time qPCR was used to detect the expression level of MXRA7 in B-ALL cell line 697 and REH cells. Lentivirus-mediated shRNA interference technology was utilized to knock down the expression of MXRA7 in REH cells. The effects of MXRA7 on the biological functions of REH cells were studied by in vitro experiments. Cell proliferation was detected by CCK-8 assay, cell cycle was detected by PI staining, cell apoptosis was detected by Annexin V and 7-AAD staining, and the expression of apoptosis pathway related proteins was detected by Western blot.@*RESULTS@#Database analysis showed that MXRA7 was highly expressed in B-ALL patients, and real-time qPCR results showed that MXRA7 was also highly expressed in cell lines 697 and REH cells. Knockdown of MXRA7 in REH cells inhibited the cell proliferation and increased the percentage of G0/G1 phase cells. After treatment with cytarabine, the apoptotic ratio was increased in MXRA7-impaired REH cells, and the activation of caspase-3 and caspase-9 were also increased.@*CONCLUSION@#Knockdown of MXRA7 can reduce the malignancy of REH cells by inhibiting the cell proliferation and increasing the sensitivity of REH cells to cytarabine. These results indicate MXRA7 may be as a novel target for the treatment of B-ALL, and the potential usefulness of MXRA7 in B-ALL deserves further investigation.

The Effect of Matrix Remodeling Associated 7 (MXRA7) Expression on the Biological Function of SHI-1 Cells / 中国实验血液学杂志

OBJECTIVE@#To express matrix remodeling associated 7 (MXRA7) in the human acute myeloid leukemia SHI-1 cell line and to assess the role of MXRA7 in the biological function of SHI-1 cells.@*METHODS@#The full-length cDNA sequence of human MXRA7 was synthesized and subcloned into the lentivirus shuttle vector pRRL-Venus. SHI-1 cells were transfected with the lentivirus which was packaged with 293T cells. The YFP-positive cells were sorted by flow cytometry and the stable cell lines were obtained by expanded culture. The expression and distribution of MXRA7 in SHI-1 cells were verified by real-time qPCR, Western blot and laser confocal techniques. Cell proliferation and cell cycle were measured by flow cytometry, and apoptosis was determined by Annexin V and 7-AAD staining. The expression of apoptosis related proteins were detected by Western blot.@*RESULTS@#The stable SHI-1 cell line overexpressing MXRA7 was established successfully. Laser confocal analysis confirmed that MXRA7 was expressed in the cytoplasm of SHI-1 cells. Compared with the control cell line, the overexpression of MXRA7 showed no effect on the cell proliferation and cell cycle, but reduced the percentage of apoptosis cells induced by methotrexate. Moreover, the expression of BCL-2 protein was increased by overexpression of MXRA7, which can inhibit cell apoptosis.@*CONCLUSION@#The SHI-1 stable cell line overexpressing MXRA7 was established successfully, and MXRA7 could inhibit drug-induced apoptosis through increasing the expression of BCL-2 protein.

Optimization of Douchi fibrinolytic enzyme production by statistical experimental methods / 华中科技大学学报（医学）（英德文版）

Thrombus disease, one of the common cardiovascular diseases, has attracted worldwide attention for its rising mortality and morbidity. Due to the distinct shortages of current fibrinolytic drugs, new fibrinolytic agents warrant investigation. In this study, 8 fibrinolytic enzyme-producing strains were isolated from Douchi-a traditional Chinese food, and strain XY-1 which produced the largest amount of the enzyme was chosen for the following experiments. The enzyme produced by strain XY-1 was named Douchi fibrinolytic enzyme (DFE). We optimized the liquid culture medium of strain XY-1 for enzyme production using Plackett-Burman and Box-Behnken design. The predicted maximal DFE yield was 19.78 FU/mL with 11.4 g/L peptone, 0.5 g/L magnesium sulfate and 1 g/L sodium chloride. However, we acquired maximal production of 21.33 FU/mL in actual experiments, equal to 107.84% of the theoretical value, and the yield had been increased by 79.55% as compared to the yield of un-optimized culture. It was demonstrated that the combined use of Plackett-Burman design and response surface methodology in fermentation optimization can effectively and rapidly increase DFE production.

Optimization of Douchi fibrinolytic enzyme production by statistical experimental methods / 华中科技大学学报（医学）（英德文版）

Thrombus disease, one of the common cardiovascular diseases, has attracted worldwide attention for its rising mortality and morbidity. Due to the distinct shortages of current fibrinolytic drugs, new fibrinolytic agents warrant investigation. In this study, 8 fibrinolytic enzyme-producing strains were isolated from Douchi-a traditional Chinese food, and strain XY-1 which produced the largest amount of the enzyme was chosen for the following experiments. The enzyme produced by strain XY-1 was named Douchi fibrinolytic enzyme (DFE). We optimized the liquid culture medium of strain XY-1 for enzyme production using Plackett-Burman and Box-Behnken design. The predicted maximal DFE yield was 19.78 FU/mL with 11.4 g/L peptone, 0.5 g/L magnesium sulfate and 1 g/L sodium chloride. However, we acquired maximal production of 21.33 FU/mL in actual experiments, equal to 107.84% of the theoretical value, and the yield had been increased by 79.55% as compared to the yield of un-optimized culture. It was demonstrated that the combined use of Plackett-Burman design and response surface methodology in fermentation optimization can effectively and rapidly increase DFE production.