Project description:BCR ligand-engaged B cells upregulate Nod1 during development. Most mature B cells have up-regulated Nod1 and are sensitive to Nod1 signaling, which increases survival upon exposure to microbial products, as a positive outcome of BCR-engaged mature B cells.
Project description:Characterization of NWD1; a novel NLR-related protein and further correlate it as a putative Prostate Cancer marker. NLRs (NACHT and Leucine Rich Repeat domain containing proteins) constitute a major subfamily of innate immunity proteins mostly acting as cytosolic pattern recognition receptors (PRRs), involved in the detection of cytoplasmic pathogen-associated molecular patterns (PAMPs) and endogenous danger signals. The recognition of the signals initiates a variety of host defense pathways through the activation of NF-kappaB, stress kinases, interferon response factors (IRFs) and/or inflammatory caspases. Despite the importance in host immune response, deregulation on NLR activities has been described in a variety of maladies, including chronic inflammation and cancer predisposition. For instance, NOD1 was one of the first NLR members shown to possibly play a role in tumorigenesis, since NOD1 stimulation induces apoptosis in MCF-7 breast carcinoma cells, and NOD1-/- MCF-7 cells generate larger tumors after injection in SCID mice. Mice deficient in NLR member NLRP3, and/or its interacting partners ASC or caspase-1, are also shown to be more susceptible to colitis-associated cancer (CAC). Polymorphisms along NLR genes NOD1 and NOD2 have also been correlated with altered cancer risk. NOD1 SNPs have been associated with gastric cancer, lymphoma, ovarian, prostate, and lung cancer due to the recognition of H. pylori (etiologic agent in gastric cancer and MALT lymphoma), C. trachomatis (putative etiologic agent in ovarian cancer), P. acnes (possible causative agent in PCa) and C. pneumonia (plausible etiological agent in lung cancer) as NOD1 ligands. Particularly, NOD1 and NOD2 have been shown to be fully operative in prostate epithelial cells and, in cooperation with TLRs, may elicit immune response during PCa progression.
Project description:Characterization of NWD1; a novel NLR-related protein and further correlate it as a putative Prostate Cancer marker. NLRs (NACHT and Leucine Rich Repeat domain containing proteins) constitute a major subfamily of innate immunity proteins mostly acting as cytosolic pattern recognition receptors (PRRs), involved in the detection of cytoplasmic pathogen-associated molecular patterns (PAMPs) and endogenous danger signals. The recognition of the signals initiates a variety of host defense pathways through the activation of NF-kappaB, stress kinases, interferon response factors (IRFs) and/or inflammatory caspases. Despite the importance in host immune response, deregulation on NLR activities has been described in a variety of maladies, including chronic inflammation and cancer predisposition. For instance, NOD1 was one of the first NLR members shown to possibly play a role in tumorigenesis, since NOD1 stimulation induces apoptosis in MCF-7 breast carcinoma cells, and NOD1-/- MCF-7 cells generate larger tumors after injection in SCID mice. Mice deficient in NLR member NLRP3, and/or its interacting partners ASC or caspase-1, are also shown to be more susceptible to colitis-associated cancer (CAC). Polymorphisms along NLR genes NOD1 and NOD2 have also been correlated with altered cancer risk. NOD1 SNPs have been associated with gastric cancer, lymphoma, ovarian, prostate, and lung cancer due to the recognition of H. pylori (etiologic agent in gastric cancer and MALT lymphoma), C. trachomatis (putative etiologic agent in ovarian cancer), P. acnes (possible causative agent in PCa) and C. pneumonia (plausible etiological agent in lung cancer) as NOD1 ligands. Particularly, NOD1 and NOD2 have been shown to be fully operative in prostate epithelial cells and, in cooperation with TLRs, may elicit immune response during PCa progression. To access a tissue-specific gene expression profile for NWD1, quantitative PCR analysis was performed using a normalized cDNA panel derived from 48 human tissues (TissueScan Tissue qPCR Array, Origene). Two apparently independent expression patterns were detected, respectively related to neurological related organs (brain, pituitary and retina) and male reproductive system (prostate, epididymis and testis), where the highest mRNA levels was observed in prostate tissue. Results were confirmed using a second set of NWD1-specific qPCR primers (data not shown). Moreover, a similar expression pattern was virtually observed using the SAGE database from the Cancer Genome Anatomy Project (CGAP) of the National Cancer Institute (not shown). Comparative gene expression microarray data was analyzed systematically by Ingenuity Pathway Analysis (IPA) to set up potential networks based on NWD1 regulated genes. The eventual participation of NWD1 in signaling transduction pathways was further examined by microarray analysis (Human WG-6v3 Expression BeadChip, Illumina) comparing the expression profile of PPC-1 cells lacking NWD1 expression (sh184 & sh3922) versus control cells (shGFP). According to the differential expression profile that was generated and analyzed by the Ingenuity PathwaysTM software (IPA version 7.1, Ingenuity Systems), NWD1 is presumably associated with biological networks related, for instance, to tissue morphology, organogenesis, cancer and neurological diseases .
Project description:Similar to resting mature B cells, where the B-cell antigen receptor (BCR) is essential for cellular survival, surface BCR expression is conserved in most mature B cell lymphomas. The identification of activating BCR mutations and the growth disadvantage upon BCR knockdown of cells of certain lymphoma entities has led to the view that BCR signaling is required for tumour cell survival. Consequently, the BCR signaling machinery has become a new target in the therapy of B cell malignancies. Here, we studied the effects of BCR ablation on MYC-driven mouse B cell lymphomas and compared them to observations in human Burkitt lymphoma. Whereas BCR ablation did not, per se, significantly affect lymphoma growth, BCR-negative (BCR-) tumour cells rapidly disappeared in the presence of their BCR-expressing (BCR+) counterparts in vitro and in vivo. This required neither cellular contact, nor factors released by BCR+ tumour cells. Instead, BCR loss induced the rewiring of central carbon metabolism increasing the sensitivity of receptor-less lymphoma cells to nutrient restriction. The BCR attenuated GSK3β activity to support MYC-controlled gene expression. BCR- tumour cells exhibited increased GSK3β activity and were rescued from their competitive growth disadvantage by GSK3β. BCR-negative lymphoma variants that restored competitive fitness, normalized GSK3β following constitutive activation of the MAPK pathway, commonly through Ras mutations. Similarly, in Burkitt lymphoma, activating RAS mutations may propagate Ig-crippled tumour cells, which usually represent a minority of the tumour bulk. Thus, while BCR expression enhances lymphoma cell fitness, BCR-targeted therapies may profit from combinations with drugs targeting BCR-less tumour cells. In this dataset, we included the expression data obtained from BCR-positive (BCR+) and BCR-negative (BCR-) lymphoma cells co-cultured for 4 days in presence or absence of GSK3b inhibitor, CHIR99021. These data were used to obtain genes that are regulated by the BCR through GSK3b inhibition.
Project description:Similar to resting mature B cells, where the B-cell antigen receptor (BCR) is essential for cellular survival, surface BCR expression is conserved in most mature B cell lymphomas. The identification of activating BCR mutations and the growth disadvantage upon BCR knockdown of cells of certain lymphoma entities has led to the view that BCR signaling is required for tumour cell survival. Consequently, the BCR signaling machinery has become a new target in the therapy of B cell malignancies. Here, we studied the effects of BCR ablation on MYC-driven mouse B cell lymphomas and compared them to observations in human Burkitt lymphoma. Whereas BCR ablation did not, per se, significantly affect lymphoma growth, BCR-negative (BCR-) tumour cells rapidly disappeared in the presence of their BCR-expressing (BCR+) counterparts in vitro and in vivo. This required neither cellular contact, nor factors released by BCR+ tumour cells. Instead, BCR loss induced the rewiring of central carbon metabolism increasing the sensitivity of receptor-less lymphoma cells to nutrient restriction. The BCR attenuated GSK3β activity to support MYC-controlled gene expression. BCR- tumour cells exhibited increased GSK3β activity and were rescued from their competitive growth disadvantage by GSK3β. BCR-negative lymphoma variants that restored competitive fitness, normalized GSK3β following constitutive activation of the MAPK pathway, commonly through Ras mutations. Similarly, in Burkitt lymphoma, activating RAS mutations may propagate Ig-crippled tumour cells, which usually represent a minority of the tumour bulk. Thus, while BCR expression enhances lymphoma cell fitness, BCR-targeted therapies may profit from combinations with drugs targeting BCR-less tumour cells. In this dataset, we included the expression data obtained from BCR-positive (BCR+), BCR-negative (BCR-) and BCR-independent lymphoma cells co-cultured for four days in presence or absence of GSK3b inhibitor, CHIR99021. This data was used to a) identify genes regulated by the BCR through GSK3b inhibition, and b) identify genes that confers BCR-independency to lymphoma variants resistant to BCR loss.
Project description:B-cell receptor (BCR) signaling promotes the survival of malignant B cells, such as Burkitt’s lymphoma (BL) and the activated B-cell-like subtype of diffuse large B cell lymphoma (ABC-DLBCL). In contrast to ABC DLBCL, where malignant cells require chronic activation of the BCR for their survival, BL cells are dependent on tonic BCR signaling that is antigen-independent. Elucidation and systematic comparison of tonic and activated BCR signaling led to the identification of novel signaling effectors, among them ACTN4 and ARFGEF2, which were identified as regulators of BL cell survival. As tonic and activated BCR signaling are relevant for important aspects of B cell biology, our study helps in gaining an understanding of BCR-induced processes not only in malignant but potentially also physiological settings.
Project description:Elevated NLR (neutrophil-lymphocyte ratio) in elective vascular surgery (EVS) patients is associated with increased mortality independent of perioperative surgical outcome. To understand why high NLR is associated with higher mortality, we investigated neutrophil and lymphocyte transcriptome expression in patients undergoing EVS.
Project description:High levels of Hes1 expression are frequently found in BCR-ABL-positive chronic myelogenous leukemia in blast crisis (CML-BC). In mouse bone marrow transplantation (BMT) models, co-expression of BCR-ABL and Hes1 induces CML-BC–like disease; however the underlying mechanism remained elusive. Here, based on gene expression analysis, we show that MMP-9 is upregulated by Hes1 in common myeloid progenitors (CMPs). Analysis of promoter activity demonstrated that Hes1 upregulated MMP-9 by activating NF-kB. Analysis of 20 samples from CML-BC patients showed that MMP-9 was highly expressed in three, with two exhibiting high levels of Hes1 expression. Interestingly, MMP-9 deficiency impaired the cobblestone area-forming ability of CMPs expressing BCR-ABL and Hes1 that were in conjunction with a stromal cell layer. In addition, these CMPs secreted MMP-9, promoting the release of soluble Kit-ligand (sKitL) from stromal cells, thereby enhancing proliferation of the leukemic cells. In accordance, mice transplanted with CMPs expressing BCR-ABL and Hes1 exhibited high levels of sKitL as well as MMP-9 in the serum. Importantly, MMP-9 deficiency impaired the development of CML-BC–like disease induced by BCR-ABL and Hes1 in mouse BMT models. The present results suggest that Hes1 promotes the development of CML-BC, partly through MMP-9 upregulation in leukemic cells. Common myeloid progenitors (CMPs; Lineage negative, c-Kit positive, Sca-1 negative, Fc-gamma-receptor low, CD34 positive fraction) were sorted with a FACSAria cell sorter (Becton Dickinson). Retroviruses were generated by transfecting Plat-E packaging cells with retrovirus vector pMYs-Hes1-IRES-GFP or empty vector (pMYs-IRES-GFP) using FuGENE 6 (Roche Diagnostics). Infection of retrovirus harboring Hes1 (pMYs-Hes1-IRES-GFP) or empty vector (pMYs-IRES-GFP) into progenitors was performed using RetroNectin (Takara Bio). Hes1-transfected CMPs and Mock-transduced CMPs were isolated 36 hours after infection with a FACSAria cell sorter. One sample of Hes1-transfected CMPs and one sample of mock-transduced CMPs were analyzed with GeneChip Mouse Genome 430 2.0 Array.
Project description:The biology of chronic myeloid leukemia (CML)-stem cells is still incompletely understood. Therefore, we previously developed an inducible transgenic mouse model in which stem cell targeted induction of BCR-ABL expression leads to chronic phase CML-like disease. Here, we now demonstrate that the disease is transplantable using BCR-ABL positive LSK cells (lin-Sca-1+c-kit+). Interestingly, the phenotype is enhanced when unfractionated bone marrow (BM) cells are transplanted. However, neither progenitor cells (lin-Sca-1-c-kit+) nor mature granulocytes (CD11b+Gr-1+), or potential stem cell niche cells were able to transmit the disease or alter the phenotype. The phenotype was largely independent of BCR ABL priming prior to transplant. However, BCR-ABL abrogated the potential of LSK cells to induce full blown disease in secondary recipients. Subsequently, we found that BCR-ABL increased the fraction of multipotent progenitor cells (MPP) at the expense of long term HSC (LT-HSC) in the BM. Microarray analyses of LSK cells revealed that BCR-ABL alters the expression of genes involved in proliferation, survival, and hematopoietic development. Our results suggest that BCR-ABL induces differentiation of LT-HSC and decreases their self renewal capacity. Furthermore, reversion of BCR-ABL eradicates mature cells while leukemic stem cells persist, giving rise to relapsed CML upon re-induction of BCR-ABL.
Project description:Survival of all B cells depends on signals from the B-cell receptor (BCR). In BCRnegative B cells the latent membrane protein 2A (LMP2A) of Epstein-Barr virus (EBV) replaces this survival signal and might play a role in the development of EBV-positive Hodgkin lymphomas and posttransplantation lymphoproliferative disease. In these BCR-negative cells LMP2A provides a ‘tonic’ signal similar to BCR’s constitutive expression in the absence of antigen in order to maintain activating signaling pathways common to both receptor molecules. In most latently EBV-infected B cells LMP2A and BCR are co-expressed but it is largely unclear what LMP2A contributes with respect to B-cell activation, proliferation and viral latency in these BCR-positive cells. A common model suggests that LMP2A maintains herpesviral latency by blocking BCR-mediated signals but how LMP2A could serve both antithetical ends in BCRnegative and BCR-positive cells is elusive. Our comparative analysis of BCR and LMP2A now indicates that LMP2A is a true BCR mimic that dominates BCR-operated signaling pathways in EBV-infected, BCR-positive cells to provide activation signals, support stable infections in vivo and allow exit from latency. These findings suggest that LMP2A co-opts the situation in anergic B cells, where continuous BCR signaling results in maintenance of the anergic state accompanied by unresponsiveness to acute BCR stimulation. The microarray experiment was used to compare effects of BCR and LMP2A on gene expression regulation. EBV's LMP2A and the human BCR activate similar cellular target genes; some genes are regulated solely by BCR or LMP2A, no gene is counter regulated A 12 chip study using cDNA from three separate 2525 LMP2A knockout LCL cultures and three separate 3696.10 LMP2A:mCD69 LCL cultures; each culture tested before and after 90 min stimulation of the BCR and LMP2A:mCD69, respectively.