Lasting B-cell persistence depends on survival signals that are transduced by cell surface receptors. Here, we describe a novel biological mechanism essential for survival and homeostasis of normal peripheral mature B cells and chronic lymphocytic leukemia (CLL) cells, regulated by the heparin-binding cytokine, midkine (MK), and its proteoglycan receptor, the receptor-type tyrosine phosphatase zeta (RPTP). We demonstrate that MK initiates a signaling cascade leading to B cell survival, by binding to RPTP. In mice lacking PTPRZ, the proportion and number of the mature B cell population is reduced. Our results emphasize a unique and critical function for MK signaling in the previously described MIF/CD74 induced survival pathway. Stimulation of CD74 with MIF leads to c-Met activation, resulting in elevation of MK expression in both normal mouse splenic B and CLL cells. Our results indicate that MK and RPTP are important regulators of the B cell repertoire. These findings could pave the way towards understanding the mechanisms shaping B cell survival, and suggest novel therapeutic strategies based on the blockade of the midkine/RPTP-dependent survival pathway.
The cytokine midkine and its receptor RPTPζ regulate B cell survival in a pathway induced by CD74.
Age
View SamplesChronic lymphocytic leukemia (CLL) is characterized by the accumulation of CD5+ B lymphocytes in peripheral blood, lymphoid organs and BM. The main feature of the disease is accumulation of the malignant cells due to decreased apoptosis. CD84 belongs to the Signaling Lymphocyte Activating Molecule (SLAM) family of immunoreceptors, and has an unknown function in CLL cells. Here, we show that the expression of CD84 is significantly elevated from the early stages of the disease, and is regulated by macrophage migration inhibitory factor (MIF) and its receptor, CD74. Activation of cell surface CD84 initiates a signaling cascade that enhances CLL cell survival. Both immune-mediated neutralization or blockade of CD84 induce cell death in vitro and in vivo. In addition, analysis of samples derived from an on-going clinical trial, in which human subjects were treated with humanized anti-CD74 milatuzumab shows a decrease in CD84 mRNA levels milatuzumab-treated cells. This downregulation was correlated with reduction of Bcl-2 and Mcl-1 message. Thus, our data show that overexpression of CD84 in CLL is an important survival mechanism that appears to be an early event in the pathogenesis of the disease. These findings suggest novel therapeutic strategies based on the blockade of this CD84-dependent survival pathway.
CD84 is a survival receptor for CLL cells.
Disease
View SamplesTo elucidate effects of tumor host interactions in vivo in CLL, purified tumor cells were obtained concurrently from blood, bone marrow and/or lymph node and analyzed by gene expression profiling.
The lymph node microenvironment promotes B-cell receptor signaling, NF-kappaB activation, and tumor proliferation in chronic lymphocytic leukemia.
Specimen part, Subject
View SamplesPreeclampsia complicates more than 3% of all pregnancies in the United States and Europe. High-risk populations include women with diabetes, dyslipidemia, thrombotic disorders, hyperhomocysteinemia, hypertension, renal diseases, previous preeclampsia, twin pregnancies, and low socioeconomic status. In the latter case, the incidence may increase to 20% to 25%. Preeclampsia is a major cause of maternal and fetal morbidity and mortality. Preeclampsia is defined by systolic blood pressure of more than 140 mm Hg and diastolic blood pressure of more than 90 mm Hg after 20 weeks gestation in a previously normotensive patient, and new-onset proteinuria. Abnormal placentation associated with shallow trophoblast invasion (fetal cells from outer cell layer of the blastocyst) into endometrium (decidua) and improper spiral artery remodeling in the decidua are initial pathological steps.
Dysregulation of the circulating and tissue-based renin-angiotensin system in preeclampsia.
No sample metadata fields
View SamplesHepG2 and THP-1 cells, the latter differentiated by phorbol 12-myristate 13-acetate (PMA), were co-cultured and characterized for typical liver-specific functions, such as xenobiotic detoxification, lipid and cholesterol metabolism. Furthermore, liver injury-associated pathways, such as inflammation, were studied. In general, the co-cultivation of these cells produced a pro-inflammatory system, as indicated by increased levels of cytokines (IL-8, TGF-α, IL-6, GM-CSF, G-CSF, TGF-β, and hFGF) in the respective supernatant. Increased expression levels of target genes of the aryl hydrocarbon receptor (AHR), e.g., CYP1A1, CYP1A2 and CYP1B1, were detected, accompanied by the increased enzyme activity of CYP1A1. Moreover, transcriptome analyses indicated a significant upregulation of cholesterol biosynthesis, which could be reduced to baseline levels by lovastatin. In contrast, total de novo lipid synthesis was reduced in co-cultured HepG2 cells. Key events of the adverse outcome pathway (AOP) for fibrosis were activated by the co-cultivation, however, no increase in the concentration of extracellular collagen was detected. This indicates, that AOP should be used with care. In summary, the indirect co-culture of HepG2/THP 1 cells results in an increased release of pro-inflammatory cytokines, an activation of the AHR pathway and an increased enzymatic CYP1A activity.
Indirect co-cultivation of HepG2 with differentiated THP-1 cells induces AHR signalling and release of pro-inflammatory cytokines.
Treatment
View SamplesTumor growth and metastasis is controlled by paracrine signaling between cells of the tumor microenvironment and malignant cells. Cancer-associated fibroblasts (CAFs), are functionally important components of the tumor microenvironment. Although some steps involved in the cross-talk between these cells are known, there is still a lot that is not clear. Thus, the addition of, the consideration of microenvironment in the development of the disease, to the clinical and pathological procedures (currently admitted as the consistent value cancer treatments) could lay the foundations for the development of new treatment strategies to control the disease.
Functional heterogeneity of cancer-associated fibroblasts from human colon tumors shows specific prognostic gene expression signature.
Specimen part
View SamplesPurpose: Evaluate gene expression profiles after inducing differentiation in cultured interstitial cystitis (IC) and control urothelial cells. Materials and Methods: Bladder biopsies were taken from IC patients and controls (women having surgery for stress incontinence). Primary cultures were grown in Keratinocyte Growth Medium with supplements. To induce differentiation, in some plates the medium was changed to DMEM-F12 with supplements. RNA was analyzed with Affymetrix chips. Three nonulcer IC patients were compared with three controls. Results: After inducing differentiation, 302 genes with a described function were altered at least 3-fold with p <0.01 in both IC and control cells. Functions of the162 upregulated genes included cell adhesion (e.g. claudins, occludin, cingulin); urothelial differentiation, retinoic acid pathway and keratinocyte differentiation (e.g. skin cornified envelope components). The 140 downregulated genes included genes associated with basal urothelium (e.g. p63, integrins ?4, ?5 and ?6, basonuclin 1 and extracellular matrix components), vimentin, metallothioneins and members of the Wnt and Notch pathways. Comparing IC vs. control cells after differentiation, only seven genes with a described function were altered at least 3-fold with p <0.01. PI3, SERPINB4, CYP2C8, EFEMP2 and SEPP1 were decreased in IC; AKR1C2 and MKNK1 were increased in IC. Conclusions: Differentiation-associated changes occurred in both IC and control cells. Comparing IC vs. control revealed very few differences. This study may have included IC patients with minimal urothelial deficiency and/or selected the cells that were most robust in culture. Also, the abnormal urothelium in IC may be due to post-translational changes and/or the bladder environment.
Differentiation associated changes in gene expression profiles of interstitial cystitis and control urothelial cells.
Disease
View SamplesTo analyze expression differences between Trp53 pro-and deficient as well as Atm pro- and deficient murine CLL tumors developing in the E-TCL1 mouse model, we analyzed splenocytes isolated from heavily infiltrated spleens of sick mice.
Two mouse models reveal an actionable PARP1 dependence in aggressive chronic lymphocytic leukemia.
Specimen part
View SamplesThe cell differentiation potential of 13-cis retinoic acid (RA) has not succeeded in the clinical treatment of glioblastoma (GBM) so far. However, RA may also induce the expression of disistance genes such as HOXB7 which can be suppressed by Thalidomide (THAL). Therefore, we tested if combined treatment with RA+THAL may inhibit growth of glioblastoma in vivo. Treatment with RA+THAL but not RA or THAL alone significantly inhibited tumour growth. The synergistic effect of RA and THAL was corroborated by the effect on proliferation of glioblastoma cell lines in vitro. HOXB7 was not upregulated but microarray analysis validated by real-time PCR identified four potential resistance genes (IL-8, HILDPA, IGFBPA, and ANGPTL4) whose upregulation by RA was suppressed by THAL. Furthermore, genes coding for small nucleolar RNAs (snoRNA) were identified as a target for RA for the first time, and their upregulation was maintained after combined treatment. Pathway analysis showed upregulation of the Ribosome pathway and downregulation of pathways associated with proliferation and inflammation. Combined treatment with RA + THAL delayed growth of GBM xenografts and suppressed putative resistance genes associated with hypoxia and angiogenesis. This encourages further pre-clinical and clinical studies of this drug combination in GBM.
Inhibition of 13-cis retinoic acid-induced gene expression of reactive-resistance genes by thalidomide in glioblastoma tumours in vivo.
Cell line, Treatment
View SamplesMicroarray analysis of gene expression in the olfactory epithelium of Harlequin mouse as a model of oxidative-stress induced neurodegeneration of olfactory sensory neurons
Cellular and molecular characterization of oxidative stress in olfactory epithelium of Harlequin mutant mouse.
No sample metadata fields
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