The role of clotting enzyme-sensitive protein-1 in the occurrence and development of GBM

THBS1 was first found in platelets, and has been confirmed in the occurrence and development of a variety of cancers, including GBM, not only regulate tumor cell behavior, but also regulate the body's immune response and promote tumor angiogenesis- Excerpted from the article(Ref: Daubon T, et alNat Commun2019 Mar 8;10 (1): 1146doi: 10.1038/s41467-019-08480-yThomas Daubon of the Institute of Medicine at the University of Bordeaux, France, and Thomas Daubon, of the Institute of Medicine, University of Bordeaux, France, published their findings in the 10th issue of the 2019 issue of the journal Nature Communication, revealing the role of the matrix cell protein family hemorrhagic globulin-1 (THBS1) in the development mechanism of glioblastoma (GBM)THBS1 was first found in platelets, and has been confirmed in the occurrence and development of a variety of cancers, including GBM, not only regulate tumor cell behavior, but also regulate the body's immune response and promote tumor angiogenesisresearchers first found that THBS1 expressed differences between levels of gliomaIt was found that THBS1 expression in GBM was highest compared to glioma II, III, or normal brain tissue, when the expression of THBS1 was assessed in immunohistology (IHC) ii, III, and IV glioma samplesThe P3 xenotransplant tumor model is very similar to human GBM, showing false fence-like cells surrounding the necrosis core, angiogenesis and invasive behaviorImmune histology showed that the invasive region of P3 tumors had higher THBS1 depositiona series of subsequent experiments confirmed that TGF beta 1 can regulate the expression of THBS1 by combining with SMAD3First, ELISA measures the expression and secretion of THBS1 in cell extracts and extracellular environment (free-THBS1), showing that specific TGF beta 1 receptor inhibitor LY2157299 can completely block the induction of TGF beta1 in cell lysate, and can also be completely blocked in the superliquationAfter analyzing the typical downstream signals of TGF beta 1, the researchers performed immunostaining of P-SMAD2, P-SMAD3 and SMAD4 and found that all SMAD proteins stimulated by TGF beta 1 were located in the U87 cell nucleusBut only the binding sites of SMAD3 were found in the human THBS1 promoterImportantly, shRNAs silent SMAD3 reduces TGF beta 1-induced THBS1 expression The activity of thBS1 promoter was inhibited when the second SMAD3 combined site mutation, and the activity of THBS1 promoter increased when the first binding site mutation was met These results show that the typical TGF beta 1 signaling pathway plays a direct role by regulating THBS1 transcription activity by SMAD3 in the type I collagen sphere attack experiment, knocking out THBS1 can lead to a significant reduction in cell attack ability Compared with the control group, differences in blood vessel types were found in tumors with thaisy1 deficiency, with a decrease in the number of small blood vessels with a length of 10 m and an increase in medium-sized blood vessels between 10 and 20 m in length Compared to the shRNA control group, the tumor attack ability of P3 THBS1-1 shRNA group decreased significantly by 49%, and the tumor attack ability of P3 THBS1-2 shRNA group decreased by 76% The survival rate of mice transfected with P3 tumors with shRNA constructs of any kind of THBS1 increased significantly To further confirm these results, the researchers used experiments using slow virus vectors to express THBS1 function in P3 cells and found an increase in the aggression of THBS1 overexpression disemored cells through Western-blot and immunofluorescent detection the researchers went on to verify that hypoxia enhances the expression of THBS1 through TGF beta 1 activation At present, anti-VEGF antibodies (bevalbezumab) of anti-angiogenic production is commonly used to treat recurrent GBM treatment The lack of oxygen in tumors and the subsequent increase in HIF1 alpha expression are the result of treatment of babezumab in the body, which may lead to an increase in localized attacks The researchers further evaluated the function of THBS1 after treatment with bevalzumab THBS1 deposition was observed in the peripheral region of P3 tumors not treated with bevalbeth monoantigen, but this was not observed in the tumor core Compared to the tumor center, thBS1 mRNA was found to be significantly increased in the immersion area In P3 tumors treated with bevalzumab, Western blot detected an increase in THBS1 expression in the core of the tumor In addition, Under in vitro hypoxic conditions, P3 and U87 cells enhance the expression of THBS1 When THBS1 shRNA transfected U87 and P3 tumors were treated with bevalbeth monoantigen, the survival rate of animal models increased significantly researchers also found that CD47/THBS1 interactions were involved in the progression of GBM Because hypoxia induces THBS1 expression, the researchers treated P3 tumors with TAX2 or control peptides under hypoxia conditions, and found that TAX2 significantly inhibited hypoxia-induced in vitro cell invasion The study showed that the vascular density of all treatment groups changed, and the combination of TAX2 and bevazumab had a stronger effect on small blood vessels Compared with the single treatment of bevalbezumab alone, the invasion of the combined therapy inhibited in the p3 intracranial tumor model was stronger than that of single bevalbezumab As a result, animal model survival increased finally, the researchers further confirmed that CD47 was a key role in GBM attacks by silence dying with CD47 in cells of Silent P3 and U87 The use of CD47 silent P3 cells to test type I collagen sphere attack showed that the invasion ability was significantly reduced Knocking out CD47 significantly weakens thbS1-induced tumor cell aggression In addition, the survival rate of P3 cells implanted in mice when CD47 was knocked out and the implanted control cells showed a significant increase in survival time in CD47 knockout groups , the study found that THBS1 was associated with the pathological level of glioma SMAD3 binds thBS1 gene promoters to the THBS1 gene in the TGF beta 1 classical pathway to regulate the transcription of THBS1 ThBS1 silence can inhibit tumor cell invasion and growth through single or combined antiangiogenic therapy, and CD47 knock-out experiments have shown that antagonistic specific inhibition of THE interaction of THBS1/CD47 reduces cell aggression RNA sequencing of peripheral and central tumor tissue spree laser micro-cutting shows that THBS1 is one of the genes with the highest connectivity at the tumor boundary Research data show that TGF beta 1 induces THBS1 expression through SMAD3, enhancing the aggression during GBM volume expansion, and CD47, which binds to tumor cells, is also involved in this process.