Expression of PSMA 7 and its effect on proliferation, invasion, migration and tumorigenesis of gastric cancer / 南方医科大学学报

OBJECTIVE@#To study the expression of PSMA7 and its effect on proliferation, invasion and migration of gastric cancer and subcutaneous tumorigenesis in nude mice. >and subcutaneous tumorigenesis in nude mice.@*METHODS@#Specimens of tumor tissues and paired adjacent tissues were collected from 60 patients with gastric cancer for detecting the expression levels of PSMA7 using immunohistochemical method. Gastric cancer cell line SGC7901 was transfected with a lentiviral vector to inhibit PSMA7 expression, and the changes in cell proliferation and invasion were observed using cell counting kit-8 (CCK-8), clone formation assay and Transwell assay. A BALB/c mouse model bearing subcutaneous gastric cancer xenograft was established using SGC7901 cells with stable PSMA7 knockdown to assess the effect of low expression of PSMA7 on xenograft growth.@*RESULTS@#Gastric cancer tissues expressed significantly higher levels of PSMA7 than the paired adjacent tissues ( < 0.05). In SGC7901 cells, interference of PSMA7 expression significantly inhibited the cell proliferation and invasion ( < 0.05). In the tumor-bearing BALB/c mice, the xenografts derived from SGC7901 cells with PSMA7 expression interference showed significant growth suppression as compared with the control xenografts ( < 0.05).@*CONCLUSIONS@#PPSMA 7 is overexpressed in gastric cancer tissues, and PSMA7 knockdown inhibits the proliferation, invasion, migration and subcutaneous tumorigenesis of gastric cancer cells in nude mice.

Salivary exosomal PSMA7: a promising biomarker of inflammatory bowel disease

Inflammatory bowel disease (IBD) is an intestinal immune-dysfunctional disease worldwide whose prevalence increasing in Asia including China. It is a chronic disease of the gastrointestinal tract with unknown cause. Exosomes are small vesicles in various body fluids. They have diameters of 40-120 nm, and one of their functions is long-distance transfer of various substances. In this study, we investigated the contents of salivary exosomes in patients with IBD and in healthy controls to explore a new biomarker in patients with IBD. In this study, whole saliva was obtained from patients with IBD (ulcerative colitis (UC), n = 37; Crohn's disease (CD), n = 11) and apparently healthy individuals (HC, n = 10). Salivary exosomes were extracted from samples, and the proteins within the exosomes were identified by liquid chromatograph-mass spectrometer (LC-MS/MS). The results showed that more than 2000 proteins were detected in salivary exosomes from patients with IBD. Through gene ontology analysis, we found that proteasome subunit alpha type 7 (PSMA7) showed especially marked differences between patients with IBD and the healthy controls, in that its expression level was much higher in the CD and UC groups. This exosomal protein is related to proteasome activity and inflammatory responses. So we conclude that in this research, salivary exosomal PSMA7 was present at high levels in salivary exosomes from subjects with IBD. It can be a very promising biomarker to release the patients from the pain of colonoscopy.

Construction of eukaryotic expression plasmid pcDNA3.1(-)/PSMA7 and its expression in A549 cell line / 解放军医学杂志

0.05). The data proved that PSMA7 was overexpressed in pcDNA3.1(-)/PSMA7-transfected A549 cell line, both in mRNA level and in protein level. Conclusion Eukaryotic expression plasmid pcDNA3.1(-)/PSMA7 has been successfully constructed, and the PSMA7 is stably expressed in A549 cell line. This would pave the way for further study of PSMA7.

Preparation and identification of the monoclonal antibody against human PSMA7 antigen / 解放军医学杂志

Objective To prepare the PSMA7 hybridoma cell lines using classical hybridoma technique and to perform purification and elementary identification of the monoclonal antibodies(McAbs)against PSMA7 antigen for further study.Methods BALB/c mice were immunized with purified recombinant PSMA7 protein.Once the antibody titer of blood taken from mouse tail reached 1∶6 400,a cell fusion was performed between mouse splenic cells and myeloma cells(Sp2/0),and then the hybridoma cell lines secreting monoclonal antibodies against PSMA7 antigen were screened by indirect enzyme linked immunosorbent assay(ELISA).The immunoglobulin subtypes and titer of the monoclonal antibodies against PSMA7 antigen were identified and measured by Western blot analysis and enzyme linked immunosorbent assay,respectively.Results After cell fusion and subcloning,two hybridoma cell lines that stably secreted monoclonal antibodies against PSMA7 antigen were successfully obtained:B013 and B001,which belong to the subtypes of IgG1.The antibody titers in the hybridoma culture supernatant were 1∶128 and 1∶256,and those in the ascites fluid were 1∶25 600 and 1∶32 000,respectively.Western blot analysis and immunohistochemistry showed that the two antibodies can specifically bind with PSMA7 antigen derived from human eucaryotic cells or tissue.Conclusions Two monoclonal antibodies against PSMA7 antigen with high titers and specificity have been successfully prepared.These antibodies can be used for the identification of PSMA7 protein,and may be a useful tool for studying the biological properties of PSMA7 protein.