Expression of CD24 gene in human malignant pleural mesothelioma and its relationship with prognosis / 中华劳动卫生职业病杂志

Objective: To investigate the expression of CD24 gene in human malignant pleural mesothelioma (MPM) cells and tissues, and evaluate its relationship with clinicopathological characteristics and clinical prognosis of MPM patients. Methods: In February 2021, UALCAN database was used to analyze the correlation between CD24 gene expression and clinicopathological characteristics in 87 cases of MPM patients. The TIMER 2.0 platform was used to explore the relationship between the expression of CD24 in MPM and tumor immune infiltrating cells. cBioportal online tool was used to analyze the correlation between CD24 and MPM tumor marker gene expression. RT-qPCR was used to analyze the expressions of CD24 gene in human normal pleural mesothelial cell lines LP9 and MPM cell lines NCI-H28 (epithelial type), NCI-H2052 (sarcoma type), and NCI-H2452 (biphasic mixed type). RT-qPCR was performed to detect the expressions of CD24 gene in 18 cases of MPM tissues and matched normal pleural tissues. The expression difference of CD24 protein in normal mesothelial tissue and MPM tissue was analyzed by immunohistochemistry. A Kaplan-Meier model was constructed to explore the influence of CD24 gene expression on the prognosis of MPM patients, and Cox regression analysis of prognostic factors in MPM patients was performed. Results: The CD24 gene expression without TP53 mutation MPM patients was significantly higher than that of patients in TP53 mutation (P<0.05). The expression of CD24 gene in MPM was positively correlated with B cells (r(s)=0.37, P<0.001). The expression of CD24 gene had a positive correlation with the expressions of thrombospondin 2 (THBS2) (r(s)=0.26, P<0.05), and had a negative correlation with the expression of epidermal growth factor containing fibulin like extracellular matrix protein 1 (EFEMP1), mesothelin (MSLN) and calbindin 2 (CALB2) (r(s)=-0.31, -0.52, -0.43, P<0.05). RT-qPCR showed that the expression level of CD24 gene in MPM cells (NCI-H28, NCI-H2052 and NCI-H2452) was significantly higher than that in normal pleural mesothelial LP9 cells. The expression level of CD24 gene in MPM tissues was significantly higher than that in matched normal pleural tissues (P<0.05). Immunohistochemistry showed that the expressions of CD24 protein in epithelial and sarcoma MPM tissues were higher than those of matched normal pleural tissues. Compared with low expression of CD24 gene, MPM patients with high expression of CD24 gene had lower overall survival (HR=2.100, 95%CI: 1.336-3.424, P<0.05) and disease-free survival (HR=1.800, 95%CI: 1.026-2.625, P<0.05). Cox multivariate analysis showed that compared with the biphasic mixed type, the epithelial type was a protective factor for the prognosis of MPM patients (HR=0.321, 95%CI: 0.172-0.623, P<0.001). Compared with low expression of CD24 gene, high expression of CD24 gene was an independent risk factor for the prognosis of MPM patients (HR=2.412, 95%CI: 1.291-4.492, P=0.006) . Conclusion: CD24 gene and protein are highly expressed in MPM tissues, and the high expression of CD24 gene suggests poor prognosis in MPM patients.

The Dual Role of LOXL4 in Pathogenesis and Development of Human Malignant Tumors / 中国生物化学与分子生物学报

Lysyl oxidase like 4 (LOXL4) is one member of the LOX protein family and is a secreted copper-dependent amine oxidase involved in the assembly and maintenance of extracellular matrix (ECM). LOXL4 is up-regulated in human liver cancer, gastric cancer, breast cancer, cervical cancer, head and neck squamous cell carcinoma, esophageal carcinoma and colorectal cancer, but down-regulated in human bladder and lung cancer. It also inhibits tumor growth in bladder and lung cancer, suggesting that L0XL4 has a dual role of promoting or inhibiting tumors in different types of human malignant tumors. L0XL4 in tumor cell exosomes promotes cell matrix adhesion and cell migration by activating the FAK/Src pathway, which is dependent on its amine oxidase activity through a hydrogen peroxide-mediated mechanism. Exosome-mediated L0XL4 can also promote tumor cell proliferation and immune escape by activating the PI3K/Akt signaling pathway. L0XL4 can be transported to macrophages via exosomes in tumor cells, where it further activates the immunosuppression function of cells and the expression of programmed death ligand 1 (PD-L1) via STAT1- and STAT3-mediated signaling pathways. It then will trigger the immunosuppressive function of macrophages and promote the immune escape of tumor cells. In addition, LOXL4 can also exert the tumor suppressive function by activating p53 and inhibiting the Ras/ERK pathway. This paper mainly reviews the structure and the function of LOXL4, and the relationship between LOXL4 and the pathogenesis and development of human malignant tumors. We then further explore the application of LOXL4 in the study of malignant tumors, laying a theoretical foundation for its future utilization in the clinical diagnosis and treatment, and screening of prognostic markers of human malignant tumors.

Prokaryotic soluble expression of protein D of Haemophilus influenzae type b / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To express the recombinant D protein in prokaryotic expression system solubly and make preparation for producing D-carrier conjugate vaccine next step.</p><p><b>METHODS</b>The hpd gene fragment removed of signal peptide from genomic DNA of Hib CMCC was inserted into pET43. 1a. The recombinant plasmid was transformed to competent E. coli BL21 (DE3) for expression under induction of IPTG. The expressed recombination protein was precipitated with ammonium sulfate, purified by DEAE anion exchange column chromatography and identified for reactogenicity by Western Blot.</p><p><b>RESULTS</b>The expressed recombination protein, in a soluble form, constained about 50% of total somatic protein and showed specific reaction with the HIB antisera after preliminary purification.</p><p><b>CONCLUSION</b>The D protein recombined expression plasmid was constructed successfully and expressed D protein in prokaryotic cells in a solube form.</p>