To explore the mechanism of brain-derived neurotrophic factor (BDNF) promoting human multiple myeloma (MM) cells secreting matrix metalloproteinase-9 ( MMP-9).Gelatin zymography of culture supernatants was performed to visualize the content of MMPs in myeloma RPMI 8226 cells stimulated by BDNF. NF-kappaB activity was determined by chemiluminescent electrophoretic mobility shift assay (EMSA).Treatment with 25, 50, 100 and 200 microg/L BDNF for 24 h significantly (P < 0.01) enhanced the level of MMP-9 (2.03+/-0.48, 2.99+/-0.046, 4.63+/-0.62 and 5.62+/-1.29 microg/L, respectively, vs 1.00 microg/L of the control) secreted by RPMI8226 cells in a dose-dependent manner, while that of MMP-2 was not changed significantly (P > 0.05). The BDNF-induced activation of MMP-9 was inhibited by pretreatment with pyrrolidine dithiocarbamate (PDTC), a NF-kappaB inhibitor, or K252 alpha, a specific tyrosine inhibitor of TrkB which is the receptor for BDNF. Pretreated with 1 mmol/L PDTC or 500 nmol/L K252 alpha significantly downregulated MMP-9 secreted by the 100 microg/L of BDNF stimulated RPMI 8226 cells (the optical density values were 867.52+/-101.81 and 727.98 +/-92.05, respectively, vs 1,159.01+/-233.15 of the control). The activity of NF-kappaB was enhanced by BDNF in a dose-dependent manner, and pretreatment with K252 alpha could significantly inhibit this activation at 1, 6, 12 and 24 h (P < 0.05) in a time-dependent manner.BDNF plays an important role in the angiogenesis of MM to promote the up-regulation of MMP-9, which may be induced by enhanced NF-kappaB activity in MM cells.
β2 adrenergic receptor (ADRB2) agonists mainly participate in regulation of airway function through the ADRB2-G protein-adenylyl cyclase (AC) signaling pathway; however, the key genes associated with this pathway and the spatiotemporal changes in the expression spectrum of some of their subtypes remain unclear, resulting in an insufficient theoretical basis for formulating the dose and method of drug administration for neonates.We performed sampling at different developmental time points in rhesus monkeys, including the embryo stage, neonatal stage, and adolescence. The MiSeq platform was used for sequencing of key genes and some of their subtypes in the ADRB2 signaling pathway in lung tissues, and target gene expression was normalized and calculated according to reads per kilobase million.At different lung-developmental stages, we observed expression of phenylethanolamine N-methyltransferase (PNMT), ADRB2, AC, AKAP and EPAC subtypes (except AC8, AKAP4/5), and various phosphodiesterase (PDE) subtypes (PDE3, PDE4, PDE7, and PDE8), with persistently high expression of AC6, PDE4B, and AKAP(1/2/8/9/12/13, and EZR) maintained throughout the lung-developmental process, PNMT, ADRB2, AC(4/6), PDE4B, and AKAP(1/2/8/9/12/13, EZR, and MAP2)were highly expressed at the neonatal stage.During normal lung development in rhesus monkeys, key genes associated with ADRB2-G protein-AC signaling and some of their subtypes are almost all expressed at the neonatal stage, suggesting that this signaling pathway plays a role in this developmental stage. Additionally, AC6, PDE4B, and AKAP(1/2/8/9/12/13, and EZR) showed persistently high expression during the entire lung-developmental process, which provides a reference for the development and utilization of key gene subtypes in this pathway.
In order to explore the probability of curcumin treating multiple myeloma (MM) via the inhibition of angiogenesis, the expressions of brain derived neurotrophic factor (BDNF) and its specific receptor in human MM cells and endothelial cells were detected by reverse transcriptase-polymerase chain reaction (RT-PCR). The angiogenic activity was evaluated by endothelial cell migration assay and tubule formation assay in vitro. The results showed that exogenous BDNF significantly induced endothelial cell tubule formation and endothelial cell migration, these two effects were inhibited by curcumin. Furthermore, BDNF was detected in the MM cell and TrkB was detected in the endothelial cell and curcumin depressed the mRNA expression of BDNF and TrkB in the dose- and time-dependent manners. It is concluded that BDNF is a novel angiogenesis protein. Curcumin interrupts the interaction between multiple myeloma cells and endothelial cells by reducing TrkB expression in endothelial cells and inhibiting BDNF production in multiple myeloma cells, eventually, resulting in inhibition of angiogenesis. This is probably one part of the mechanism of the curcumin treating MM via the inhibition of angiogenesis.
Objective To study the localization of follicle stimulating hormone(FSH),its receptor(FSHR) and their mRNA in pancreas of rats to provide theoretic evidence for further study of FSH function in pancreas.Methods Singlestaining immunofluorescence and in situ hybridization methods were used.Results FSH protein and mRNA,and FSHR protein and mRNA immunofluorescence positive staining was localized in most of rat islet cells and partial pancreas exocrine cells,positive material distributed in the cytoplasm,not in nuclei.Conclusion Presentation of both FSH and FSHR in rat pancreas indicates that FSH may be involved in the functional regulation of pancreas through autocrine or paracrine activity.
Endothelial differentiation gene (edg)-encoded G protein-coupled receptors (Edg Rs)-1, -3, and -5 bind sphingosine 1-phosphate (S1P), and Edg-2 and -4 bind lysophosphatidic acid (LPA). Edg Rs transduce signals from LPA and S1P that stimulate ras- and rho-dependent cellular proliferation, enhance cellular survival, and suppress apoptosis. That high levels of LPA in plasma and ascitic fluid of patients with ovarian cancer correlate with widespread invasion suggested the importance of investigating expression and functions of Edg Rs in ovarian cancer cells (OCCs) as compared with nonmalignant ovarian surface epithelial cells (OSEs). Analyses of Edg Rs by semiquantitative reverse transcription-PCR, a radioactively quantified variant of PCR, and Western blots developed with monoclonal antibodies showed prominent expression of Edg-4 R in primary cultures and established lines of OCCs but none in OSEs. In contrast, levels of Edg-2, -3, and -5 were higher in OSEs than OCCs. LPA stimulated proliferation and signaled a serum response element-luciferase reporter of immediate-early gene activation in OCCs but not OSEs, whereas S1P evoked similar responses in both OSEs and OCCs. Pharmacological inhibitors of Edg R signaling suppressed OCC responses to LPA. A combination of monoclonal anti-Edg-4 R antibody and phorbol myristate acetate, which were inactive separately, evoked proliferative and serum response element-luciferase responses of OCCs but not OSEs. Thus the Edg-4 R may represent a distinctive marker of OCC that transduces growth-promoting signals from the high local concentrations of LPA characteristic of aggressive ovarian cancer.
CARD11 is a lymphoid lineage-specific scaffold protein regulating the NF-κB activation downstream of the antigen receptor signal pathway. Defective CARD11 function results in abnormal development and differentiation of lymphocytes, especially thymic regulatory T cells (Treg).
Background: Despite of the paradigm change on the treatments of acute myeloid leukemia (AML) and chronic lymphocytic leukemia (CLL) by venetoclax, it has been less successful in the treatment of diffuse large B-cell lymphoma (DLBCL).Here, we explored whether acylglycerol kinase regulates the sensitivity of DLBCLs to venetoclax and its mechanism in both cell lines and preclinical animal models.Methods: The expression of AGK and sensitivity to venetoclax of seven DLBCL cell lines were determined.Upon knockdown and overexpression of AGK by lentivirus in DLBCL cells, the venetoclax-induced apoptosis and PTEN-FOXO1-BCL-2 signaling axis were evaluated in vitro.The efficacy of venetoclax and PTEN-FOXO1-BCL-2 signaling axis were evaluated in immunodeficient NCG mice that were implanted with control or shAGK stably transduced SU-DHL4 cells.The expressions of AGK, BCL-2 and FOXO1 were evaluated in tumor tissues of DLBCL patients.Results: AGK expression was inversely correlated with sensitivity of DLBCL to venetoclax.Inhibition of AGK rendered the DLBCL cells more sensitive to venetoclax.Mechanistically, AGK phosphorylated and inactivated PTEN, which led to AKT activation and reduced FOXO1 nuclear translocation.Inhibition of AGK also led to enhanced efficacy of venetoclax for suppression of DLBCL tumor growth in vivo, which was dependent on FOXO1.In human DLBCL tumor tissues, the expression of AGK inversely correlated with BCL-2 expression, as well as the amounts of nuclear FOXO1.Conclusions: Our data demonstrated that AGK regulates venetoclax response in DLBCL via PTEN-FOXO1-BCL-2 signaling axis.Targeting AGK may enhance the efficacy of venetoclax for the treatment of DLBCL patients.