Ruxolitinib, a Janus Kinase (JAK)-1 and -2 Inhibitor Modulates Microrna (miR) Levels in Patients with Myelofibrosis (MF): miR Levels Might Predict MF Treatment Outcome

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 1744-1744
Author(s):  
Taghi Manshouri ◽  
Zeev Estrov ◽  
Liza Knez ◽  
Ying Zhang ◽  
Ross L Levine ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Mononuclear Cells ◽  
Myeloproliferative Neoplasms ◽  
Hematologic Malignancies ◽  
Janus Kinase ◽  
Rnase Iii ◽  
Downstream Signaling ◽  
Protein Levels ◽  
Cancer Pathogenesis ◽  
Clinical Benefits

Abstract Abstract 1744 Myeloproliferative neoplasms (MPN) are a class of stem cell–derived hematologic malignancies, characterized by an expansion of one or more myeloid lineages with resulting bone marrow (BM) hypercellularity. A gain-of-function mutation in JAK2, detected in most patients with MPN, induces constitutive activation of JAK2, stimulation of downstream signaling pathways, and activation of several cytokine and growth factor genes. Recent phase I/II clinical trial revealed that ruxolitinib (INCB018424), an oral inhibitor of JAK1 and JAK2, induced marked and durable clinical benefits in patients with primary or secondary MF (Verstovsek S et al. N Engl J Med 12:1117, 2010). Although clinically effective, ruxolitinib induced a modest (13%) suppression of the JAK2V617F allele burden after 12 cycles of therapy and the response did not correlate with the presence of JAK2V617 mutation. Therefore other, yet unknown, mechanisms might be operative in attaining these clinical benefits. Alterations in gene and protein levels affect miRs levels, and miRs have been shown to regulate protein levels, thereby playing a role in cancer pathogenesis (Calin G, et al. PNAS 99:15524, 2002; Merritt MW et al. N Engl J Med 25:2641, 2008; Munker R, et al, Clin Sci 121:141, 2011). Therefore, in MF patients we investigated changes in the levels of RNase III enzymes Dicer and Drosha, which are the two main regulators of miR biogenesis. Deregulation of their expression has been indicative of possible miR alterations in various cancers. We also investigated expression of several miRs (h-miR-16, 21, 29a, 29b1, 29b2, 29c, 155, 181a, and 451). Bone marrow mononuclear cells (MNC) from six best responders in the ruxolitinib study, and MNC from six worst responders were collected (at baseline, one year and two years on therapy), plus six normal control bone marrow MNC, and used for this study. Using qRT-PCR we found that the levels of miR-16, -21, -29 (a, b1, b2, c), -155, -188a and -451 were significantly higher in MF than in normal controls. MiR-155 levels were significantly higher at baseline in best responders than worst responders (P = 0.024). However, after two years of treatment they significantly declined (P = 0.055). The expression of miR-188a was also significantly higher in the worst responders at baseline, as compared to the best responders, but stayed elevated during two years of therapy (P = 0.0021). The levels of RNase III enzymes Dicer and Drosha were significantly lower at baseline in MF MNC as compare to normal MNC. However, after two years of treatment, Dicer level significantly increased in the best responders but not in the worst responders (P = 0.0001). In conclusion, ruxolitinib treatment modulates miR levels and associated enzymes; miR profiling might be useful in predicting response to ruxolitinib. Disclosures: Verstovsek: Incyte Corporation: Research Funding.

SGN-70, a Humanized Anti-CD70 Antibody, Targets CD70-Expressing Hematologic Tumors.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 2492-2492
Author(s):  
Julie A. McEarchern ◽  
Charlotte F. McDonagh ◽  
Leia M. Smith ◽  
Kerry Klussman ◽  
Ezogelin Oflazoglu ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Mononuclear Cells ◽  
Hematologic Malignancies ◽  
Myeloma Cell ◽  
Long Bone ◽  
Protein Levels ◽  
Normal Tissues ◽  
Significant Expression

Abstract Antigens expressed on malignant cells in the absence of significant expression on normal tissues are highly desirable targets for therapeutic antibodies. CD70 is a TNF superfamily member whose normal expression is restricted to activated lymphocytes but is aberrantly expressed in hematologic malignancies and solid tumors including non-Hodgkin’s lymphoma (NHL), Hodgkin’s disease, multiple myeloma (MM), Waldenstrom’s macroglobulinemia, renal cell carcinoma, glioblastoma, and nasopharyngeal carcinoma. To target CD70-expressing hematologic malignancies, we have engineered a humanized IgG1 anti-CD70 antibody that mediates lysis of tumor targets via ADCC and CDC and facilitates antibody dependent cellular phagocytosis in vitro. In vivo, administration of SGN-70 prolonged survival of SCID mice bearing CD70+ disseminated human NHL or MM xenografts. Intravenous injection of the CD70+ MM cell line MM.1S resulted in disease as measured by onset of paralysis, presence of CD138+ MM cells in the bone marrow, and increasing levels of circulating human Ig lambda light chain. SGN-70 treatment of MM.1S-bearing mice significantly delayed onset of paralysis and reduced the monoclonal protein levels detected in serum approximately 4-fold compared to untreated or non-binding antibody control-treated mice. Whereas myeloma cells comprised 32±6.4 % of mononuclear cells in the long bone marrow of control mice, SGN-70 treatment reduced the myeloma cell fraction to 4.9±1.9% of mononuclear cells recovered. SGN-70 treatment also significantly extended the survival of mice bearing disseminated Raji tumors (NHL) compared to control mice. Survival benefit was absent when mice received an Fc-modified antibody deficient in effector functions, confirming that the activity of SGN-70 in these models was dependent upon Fc-FcγR interaction with host immune cells. Together, these data demonstrate that SGN-70 possesses effector cell-mediated antitumor activity and provides rationale for clinical study of SGN-70 in CD70+ hematologic malignancies.

scholarly journals STAT5 is Expressed in CD34+/CD38− Stem Cells and Serves as a Potential Molecular Target in Ph-Negative Myeloproliferative Neoplasms

Cancers ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 1021 ◽  
Author(s):  
Emir Hadzijusufovic ◽  
Alexandra Keller ◽  
Daniela Berger ◽  
Georg Greiner ◽  
Bettina Wingelhofer ◽  
...  
Keyword(s):  
Stem Cells ◽  
Myeloproliferative Neoplasms ◽  
Jak2 V617f ◽  
Primary Myelofibrosis ◽  
Janus Kinase ◽  
Signaling Cascades ◽  
Nuclear Compartment ◽  
Downstream Signaling ◽  
Direct Targeting ◽  
Calr Mutations

Janus kinase 2 (JAK2) and signal transducer and activator of transcription-5 (STAT5) play a key role in the pathogenesis of myeloproliferative neoplasms (MPN). In most patients, JAK2 V617F or CALR mutations are found and lead to activation of various downstream signaling cascades and molecules, including STAT5. We examined the presence and distribution of phosphorylated (p) STAT5 in neoplastic cells in patients with MPN, including polycythemia vera (PV, n = 10), essential thrombocythemia (ET, n = 15) and primary myelofibrosis (PMF, n = 9), and in the JAK2 V617F-positive cell lines HEL and SET-2. As assessed by immunohistochemistry, MPN cells displayed pSTAT5 in all patients examined. Phosphorylated STAT5 was also detected in putative CD34+/CD38− MPN stem cells (MPN-SC) by flow cytometry. Immunostaining experiments and Western blotting demonstrated pSTAT5 expression in both the cytoplasmic and nuclear compartment of MPN cells. Confirming previous studies, we also found that JAK2-targeting drugs counteract the expression of pSTAT5 and growth in HEL and SET-2 cells. Growth-inhibition of MPN cells was also induced by the STAT5-targeting drugs piceatannol, pimozide, AC-3-019 and AC-4-130. Together, we show that CD34+/CD38− MPN-SC express pSTAT5 and that pSTAT5 is expressed in the nuclear and cytoplasmic compartment of MPN cells. Whether direct targeting of pSTAT5 in MPN-SC is efficacious in MPN patients remains unknown.

Direct Activation of STAT5 by TEL-Lyn Fusion Protein Promotes Induction of Myeloproliferative Neoplasms with Myelofibrosis

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 4114-4114
Author(s):  
Yusuke Takeda ◽  
Chiaki Nakaseko ◽  
Hiroaki Tanaka ◽  
Masahiro Takeuchi ◽  
Makiko Yui ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Myeloproliferative Neoplasms ◽  
Jak2 V617f ◽  
Signaling Molecules ◽  
Janus Kinase ◽  
Idiopathic Myelofibrosis ◽  
Lyn Kinase

Abstract Abstract 4114 Background Myeloproliferative neoplasms (MPN), a group of hematopoietic stem cell (HSC) disorders, are often accompanied by myelofibrosis. The V617F somatic mutation in the Janus kinase 2 (JAK2) gene has recently been found in the majority of patients with polycythemia vera (PV) and more than half of patients with essential thrombocythemia (ET) and idiopathic myelofibrosis (IMF). The expression of JAK2 V617F causes a PV-like disease with myelofibrosis in a murine bone marrow (BM) transplant model. In addition, a gain-of-function c-MPL W515 mutation was described in nearly 10% of patients with JAK2 V617F-negative IMF. However, the mechanism responsible for MPD and the formation of myelofibrosis in patients without JAK2 or c-MPL mutations is still unclear. We previously identified the fusion of the TEL gene to the Lyn gene (TEL-Lyn) in idiopathic myelofibrosis with ins(12;8)(p13;q11q21). The introduction of TEL-Lyn into HSCs resulted in fatal MPN with massive myelofibrosis in mice, implicating the rearranged Lyn kinase in the pathogenesis of MPN with myelofibrosis. However, the signaling molecules directly downstream from and activated by TEL-Lyn remain unknown. Design and Methods We examined the signaling pathways activated by TEL-Lyn by Western blotting, immunoprecipitation, and in vitro kinase assay using a TEL-Lyn kinase-dead mutant as a control. We further characterized the functional properties of Stat5-deficient HSCs transduced with TEL-Lyn by colony-forming assay and bone marrow transplantation to evaluate the role of STAT5 in TEL-Lyn-induced MPN. Results TEL-Lyn was demonstrated to be constitutively active as a kinase through autophosphorylation. In TEL-Lyn-expressing cells, STAT5, STAT3, and Akt were constitutively activated. Among these signaling molecules, STAT5 was activated most prominently and this occurred without the activation of Jak2, the major kinase for STAT5. TEL-Lyn was co-immunoprecipitated with STAT5, and STAT5 was phosphorylated when incubated with TEL-Lyn, but not with TEL-Lyn kinase-dead mutant. These results indicate that TEL-Lyn interacts with STAT5 and directly activates STAT5 both in vitro and in vivo. Of note, the capacity of TEL-Lyn to support the formation of hematopoietic colonies under cytokine-free conditions in vitro and to induce MPN with myelofibrosis in vivo was profoundly attenuated in a Stat5-null background. Conclusions In this study, we clearly showed that TEL-Lyn directly activates STAT5 and the capacity of TEL-Lyn to induce MPN with myelofibrosis was profoundly attenuated in the absence of STAT5. Our findings of TEL-Lyn in this study support the role of the Src family kinases in the regulation of STAT pathways and implicate active Lyn in the alternative pathway for STAT activation in pathological cytokine signaling. Our mouse model of MPD with myelofibrosis would be beneficial for the analysis of therapeutic approaches for myelofibrosis. Disclosures: No relevant conflicts of interest to declare.

The Effects Of IL-9 On CLL Correlate With Activation Of The JAK/STAT Pathways and Micrornas

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 1627-1627
Author(s):  
Na Chen ◽  
Xin Wang ◽  
Li Peipei ◽  
Xiao Lv ◽  
Kang Lu
Keyword(s):  
Western Blot ◽  
Time Course ◽  
Mononuclear Cells ◽  
Conflicts Of Interest ◽  
Elevated Serum ◽  
Lymphocytic Leukemia ◽  
Janus Kinase ◽  
Clinical Staging ◽  
Signal Transducer ◽  
Protein Levels

Abstract Background Chronic lymphocytic leukemia (CLL) is a common leukemia in adults, but its pathogenesis is still poorly understood. Interleukin-9(IL-9) has pleiotropic functions in hematological malignancies. Phosphorylation (p) of signal transducer and activator of transcription (STAT) occurs in hematologic malignancies, including STAT3 and STAT6. Studies from cell culture and animal models have revealed that the Janus kinase-signal transducer and activator of transcription (Jak-STAT) signaling pathway, which can be activated by sorts of cytokines involved IL-9. Circulating microRNAs(miRNAs) can be sensitive biomarkers for CLL and STAT3 stimulation induced miR-155 and miR-21 upregulation in CLL cells. Objective The expressions of IL-9, pSTAT3, pSTAT6, miR-155 and miR-21 were detected in CLL patients. We strived to prove that STAT3 and STAT6 phosphorylation may play a key regulating role in the secretion of IL-9, which may affect the proliferation and apoptosis of CLL cells. We also examined whether the overexpressions of miR155 and miR21 genes promote IL-9 production and STAT3 affects the transcription of miR155 and miR21 in CLL cells. Methods We measured serum levels of IL-9 in 47 patients with CLL and healthy controls using ELISA. Expressions of pSTAT3 and pSTAT6 were evaluated by Western blot in peripheral blood mononuclear cells (PBMCs) from 20 CLL patients with upregulation of IL-9 and B cells from healthy samples. Analyses of miRNA155 and miRNA21 expressions were conducted on 20 patient samples and healthy samples through qPCR. IL-9 production was detected by Western blot and qPCR in both IL-9 stimulated CLL cells (MEC-1) and miR-transfected MEC-1 cells at different time point. And then the IL-9 secreting was detected after these cells exposed to WP1066 or A77-1726 for 48 hours. Finally, we observed that cell proliferation with CCK-8 incorporation assay and cell apoptosis using AnnexinV-FITC/PI staining followed by flow cytometry. Results An elevated serum level of IL-9 was detected in 20 of 47 sera from CLL patients (Figure 1A). Sera IL-9 level was correlated with the clinical staging, ZAP-70 expression, B2M expression and IgVH status of CLL patients. (P<0.05,Table 1). Overexpressions of pSTAT3, pSTAT6 in protein levels were detected in 20 CLL patients with upredulation of IL-9(Figure 1B-C), while expressions of miRNA 155 and miRNA21 were elevated in 20 CLL patients. The tyrosine STAT3 and STAT6 phosphorylation in MEC-1 cells stimulated by 20ng/mL IL-9 with time course was associated with an increase of the IL-9 secreting with time dependence. MEC-1 cells stimulated with IL-9 by a time course followed by treatment of Wp1066 (10ng/mL) and A77-1726(10ng/mL) eliminated the IL-9 secreting (Figure 1D). IL-9 protein levels were increased in miR-155 transfected MEC-1 cells and miR21 transfected MEC-1 cells treated with 10ng/mL IL-9 at 120min compared with untransfected cells. However Wp1066 could inhibit these facts (Figure 1E). The MEC-1 apoptoses inhibited and the proliferation enhanced by IL-9(20ng/ml) could be blocked by Wp1066 and A77-1726 (Figure 2A-B). MEC-1 cells transfected with miR-155 and miR21 could promote all these effects of IL-9, which inhibited by Wp1066 (Figure 2C-D). Conclusion Our findings suggest that a new explanation about the possible molecular mechanism of regulation of IL-9 production in CLL. It may provide useful insights in understanding the cross-talking pathways among IL-9, STAT3, STAT6, miR-155 and miR-21, which promote the pathogenesis of CLL. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Molecular insights into regulation of JAK2 in myeloproliferative neoplasms

Blood ◽  
2015 ◽  
Vol 125 (22) ◽  
pp. 3388-3392 ◽  
Author(s):  
Olli Silvennoinen ◽  
Stevan R. Hubbard
Keyword(s):  
Molecular Characterization ◽  
Human Disease ◽  
Molecular Mechanisms ◽  
Myeloproliferative Neoplasms ◽  
Critical Role ◽  
Hematologic Malignancies ◽  
Janus Kinase ◽  
Constitutive Activation

Abstract The critical role of Janus kinase-2 (JAK2) in regulation of myelopoiesis was established 2 decades ago, but identification of mutations in the pseudokinase domain of JAK2 in myeloproliferative neoplasms (MPNs) and in other hematologic malignancies highlighted the role of JAK2 in human disease. These findings have revolutionized the diagnostics of MPNs and led to development of novel JAK2 therapeutics. However, the molecular mechanisms by which mutations in the pseudokinase domain lead to hyperactivation of JAK2 and clinical disease have been unclear. Here, we describe recent advances in the molecular characterization of the JAK2 pseudokinase domain and how pathogenic mutations lead to constitutive activation of JAK2.

scholarly journals Defective interleukin 2 production in patients after bone marrow transplantation and in vitro restoration of defective T lymphocyte proliferation by highly purified interleukin 2

Blood ◽  
1984 ◽  
Vol 64 (2) ◽  
pp. 380-385 ◽  
Author(s):  
K Welte ◽  
N Ciobanu ◽  
MA Moore ◽  
S Gulati ◽  
RJ O'Reilly ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Mononuclear Cells ◽  
Interleukin 2 ◽  
Autologous Bone Marrow ◽  
Hematologic Malignancies ◽  
Allogeneic Bone ◽  
Peripheral Blood Mononuclear ◽  
T Lymphocyte Proliferation ◽  
Conditioning Regimens

Using OKT3 monoclonal antibody as a mitogen, we have studied interleukin 2 (IL2) production and proliferation in peripheral blood mononuclear cells (PBMC) of 23 patients receiving bone marrow transplants. Twenty patients were recipients of allogeneic bone marrow for treatment of hematologic malignancies, aplastic anemias (AA), or severe combined immunodeficiencies (SCID). Three patients with Hodgkin's disease or neuroblastoma received autologous bone marrow. Endogenous IL2 production was not detectable (less than 0.2 U/mL) in PBMC of 18 patients and was very low in PBMC from five patients (0.5 to 1.5 U/mL), as compared to normal controls (median 3.5 U/mL) or pretransplant patients (median 1.5 U/mL). The low IL2 production was associated with defective OKT3-induced proliferation of PBMC in 19 of 23 patients studied. In the first 6 months after BMT, 14 of 15 patients (93%) showed defective proliferation of PBMC as compared to five of eight patients (63%) tested between 7 and 18 months after BMT (P less than .1). In all but three patients, addition of highly purified human lymphocyte IL2 (hpIL2) restored OKT3-induced proliferation of PBMC to within the normal range. This study demonstrates that PBMC in patients after BMT have a defect of IL2 production but are able to express IL2 receptors in response to OKT3 antibody and to proliferate normally upon addition of hpIL2. PBMC of all patients showed similar functional defects, whether or not they received additional therapy, including various conditioning regimens prior to BMT and immunosuppressive therapy after BMT. These observations suggest that T cell defects after BMT are most likely secondary to quantitative or qualitative defects of transplanted T lymphocytes or their precursors.

Transcriptome Profiling of Pediatric Myeloproliferative Neoplasms Demonstrates Dysregulation of Platelet-Relevant Genes and Enrichment of Inflammatory and JAK2 Mediated Complement Pathways

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 4203-4203
Author(s):  
Nicole Kucine ◽  
Amanda R. Leonti ◽  
Aishwarya Krishnan ◽  
Rhonda E. Ries ◽  
Ross L. Levine ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Board Of Directors ◽  
Platelet Activation ◽  
Research Funding ◽  
Mononuclear Cells ◽  
Myeloproliferative Neoplasms ◽  
Differentially Expressed ◽  
Rna Seq ◽  
Advisory Committees ◽  
Normal Controls

Introduction : Myeloproliferative neoplasms (MPNs) are rare clonal bone marrow disorders in children characterized by high blood counts, predisposition to clotting events, and the potential to transform to myelofibrosis or acute myeloid leukemia (AML). Children with MPNs have lower rates of the known driver mutations (in JAK2, MPL, and CALR) than adult patients, and the underlying pathways and molecular derangements in young patients remain unknown. Given the lack of knowledge about pediatric MPNs, it is critical that we gain a better understanding of the dysregulated pathways in these diseases, which is necessary for improving disease understanding and broadening treatment options in children. Therefore, the objective of this work was to identify differentially expressed genes and pathways between children with MPNs and healthy controls, as well as children with AML, to guide further study. Methods : Mononuclear cells were extracted from peripheral blood of pediatric MPN patients (n=20) and pediatric and young adult AML patients (n=1410), and bone marrow of normal controls (NC, n=68). AML patient samples were being evaluated as part of a Children's Oncology Group planned analysis. To identify an expression profile unique to MPNs, transcriptome data from MPN patients was contrasted against NC and AML patients. All samples were ribodepleted and underwent Illumina RNA-Seq to generate transcriptome expression data. All analyses were performed in R. Differentially expressed genes were identified using the voom function from the limma package (v. 3.38.3), and enriched pathways were identified using the pathfindR package (v. 1.3.1). Unsupervised hierarchical clustering and heatmap generation was performed using the ComplexHeatmap package (v. 1.20.0). Results : MPN patient samples showed a unique expression signature, distinct from both AML patients and normal controls. Unsupervised PCA plot (Figure 1A) and heatmaps (Figure 1B) show that MPN samples cluster together. There were 4,012 differentially expressed (DE) genes in MPNs compared to NC and 6,743 DE genes in MPNs compared to AML patients. There were 2,493 shared genes between the 2 groups (Figure 1C.) Significantly DE genes between MPNs and other groups included multiple platelet-relevant genes including PF4 (CXCL4), PF4V1, P2RY12, and PPBP (CXCL7). Interestingly, PF4V1 was the most DE gene in MPNs compared to AML, and third highest versus NC. Dysregulation of some of these genes has been seen in adult MPNs, as well as thrombosis. Further comparison of transcriptome profiles between children with (n=13) and without (n=7)JAK2 mutations showed upregulation of three genes, CFB, C2, and SERPING1, which are all known complement genes, implicating complement activation in JAK2-mutated MPN patients. Complement activation has previously been reported in adult MPNs. Pathway enrichment analysis shows a number of immune and inflammatory pathways as enriched in MPN patients compared to both AML and NC. There were 179 enriched pathways in MPNs compared to AML and 142 compared to NC, with 134 common pathways (Figure 1D.) The systemic lupus erythematosus pathway was the most heavily enriched pathway in MPNs compared to both AML and NC. Additional pathways with significant enrichment include hematopoietic cell lineage, cytokine-cytokine interactions, DNA replication, and various infection-relevant pathways. The JAK-STAT signaling pathway was also enriched in MPNs compared to both AML and NC, as was the platelet activation pathway. Conclusion: Transcriptome evaluation of childhood MPNs shows enrichment of numerous inflammatory and immune pathways, highlighting that, as in adult MPNs, inflammation is implicated in pediatric MPNs. Furthermore, specific complement genes were upregulated in JAK2-mutant MPN. Upregulation of platelet-specific genes implies potential insights into disease mechanisms and warrants more study. Variations in the cell populations may account for some of the differences seen, however all samples were largely mononuclear cells, making their comparisons reasonable. Further analysis of this early data is needed to better assess inflammatory changes and platelet activation in pediatric MPNs, as are larger sample sizes. Individual cells may have differential expression of various genes, and future experiments with single-cell RNA-seq would be helpful to further elucidate differences. Disclosures Levine: Novartis: Consultancy; Loxo: Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Research Funding; Gilead: Consultancy; Roche: Consultancy, Research Funding; Lilly: Honoraria; Amgen: Honoraria; Qiagen: Membership on an entity's Board of Directors or advisory committees; Imago Biosciences: Membership on an entity's Board of Directors or advisory committees; C4 Therapeutics: Membership on an entity's Board of Directors or advisory committees; Prelude Therapeutics: Research Funding; Isoplexis: Membership on an entity's Board of Directors or advisory committees.

Livin Expression in Normal Hematopoietic Cells and in Hematologic Malignancies.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 4301-4301
Author(s):  
Ihab Abd-Elrahman ◽  
Vered Bucholtz ◽  
Klilah Hershko ◽  
Gail Amir ◽  
Riki Perlman ◽  
...  
Keyword(s):  
Bone Marrow ◽  
B Cells ◽  
Peripheral Blood ◽  
Mononuclear Cells ◽  
Hematopoietic Cells ◽  
Hematologic Malignancies ◽  
Inhibitor Of Apoptosis ◽  
Mrna Levels ◽  
Rt Pcr ◽  
Immunohistochemistry Staining

Abstract Livin is a member of the Inhibitor of Apoptosis Proteins (IAP) family, a novel family of intracellular anti-apoptotic proteins that act by binding and inhibiting caspases. We found that Livin is unique among the IAP members as upon strong apoptotic stimuli, it is specifically cleaved by caspases to produce a large C-terminal subunit. This subunit has a paradoxical pro-apoptotic activity. Thus, Livin is not merely an inhibitor of apoptosis. Rather, it is a regulator of apoptosis that can protect against apoptosis but upon continuous apoptotic signals it helps to assure cell death. We showed that Livin plays a major role in melanoma. The level of the Livin protein is directly correlated to the resistance of melanoma cells to chemotherapy and to the survival rate of melanoma patients. Livin was also shown to be over expressed in other solid tumors such as nasopharyngeal, neuroblastoma, colorectal and lung cancers. In this work we studied Livin expression in normal hematopoietic cells as well as hematologic malignancies. Using immunohistochemistry staining for Livin we evaluated its expression in reactive lymph nodes (LN) and showed that in contrast to Bcl2, Livin was detected in highly proliferating germinal centers. In normal bone marrow Livin was detected in Megakaryocytes and immature myeloid precursors. In peripheral blood mononuclear cells, using quantitative RT-PCR, we found that Livin expression was down regulated in activated monocytes and T cells while in B cells, Livin was upregulated upon activation. We studied bone marrow and LNs from 84 patients (pts) with hematologic malignancies. Positive immunohistochemistry staining was found in the malignant cells of all pts with DLBC NHL (31 pts), follicular lymphoma (12 pts) and multiple myeloma (15 pts). Peripheral blood samples from 28 B-CLL pts were compared with healthy controls’ B cells. High mRNA levels were detected in 43% of the pts, in correlation with older age (p&lt;0.05). On the other hand, Livin was not expressed in Hodgkin’s disease (4 pts and 4 cell lines) and only 6/29 pts with AML had high levels of Livin in RT-PCR without any clinical correlation. Our data demonstrate that Livin is over expressed in activated normal B cells both in peripheral blood and LN as well as in most B cell lymphoproliferative diseases. Further investigation will establish the role of Livin over expression in hematologic malignancies.

Increased Bone Marrow Microvascular Density in Hematologic Malignancies

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 5456-5456
Author(s):  
Helene Francisca Stigter Negaard ◽  
Nina Iversen ◽  
Inger Marie Bowitz-Lothe ◽  
Per Morten Sandset ◽  
Brit Steinsvik ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Growth Factor ◽  
Plasma Levels ◽  
Mononuclear Cells ◽  
Plasma Concentrations ◽  
Hematologic Malignancies ◽  
Study Cohort ◽  
Advanced Stage ◽  
Lower Stage ◽  
Stage Disease

Abstract Background: Angiogenesis is a potential target for therapy, both in solid tumors and in hematologic malignancies. However, the regulation of angiogenesis is complex, different cancers are inherently heterogeneous, and these drugs target different angiogenic regulators. Therefore, a detailed characterization of angiogenesis in individual cancers is needed. Materials and methods: The study cohort consisted of 93 consecutive patients with hematologic neoplasia; i.e. acute myeloid leukemia (n=20), chronic lymphatic leukemia (n=14), multiple myeloma (n=11), and non-Hodgkin’s lymphoma (NHL, n=48). We determined the microvessel density (MVD) in bone marrow biopsy specimens by immunohistochemical staining for CD34. In addition, we measured the plasma concentrations of eight putative angiogenesis regulators using Luminex multiplex assay, and the expression in peripheral blood mononuclear cells (PBMNC) of 40 angiogenesisrelated mRNAs using quantitative RT-PCR. Results: Untreated patients had increased bone marrow MVD (mean 39 microvessels/mm2) compared to healthy subjects (mean 20 microvessels/mm2; p&lt;0.001). In particular, patients with advanced stage disease had increased bone marrow MVD (mean 45 microvessels/mm2) compared to patients with lower stage disease (mean 35 microvessels/mm2, p=0.030). A novel finding was that patients with NHL also had significantly increased bone marrow MVD (mean 38 microvessels/mm2). The patients had increased plasma levels of vascular endothelial growth factor (VEGF; mean 31 vs 19 pg/ml, p&lt;0.001), interleukin (IL)-6 (median 4.6 vs 2.3 pg/ml, p=0.034) and IL-8 (median 7.2 vs 3.9 pg/ml, p=0.001). Plasma levels of fibroblast growth factor 2 (FGF2), tumor necrosis factor α, and angiogenin were not significantly different in patients compared to controls. Pre-treatment plasma levels of VEGF and FGF2 were significantly higher in those who did not achieve complete remission after cancer therapy. Patients with advanced stage disease had significantly higher plasma levels of IL-6 and -8. The mRNA most highly expressed in PBMNC was IL8, which was 15-fold up-regulated. The mRNA expression of VEGFA in PBMNC was strongly correlated to the expressions of hypoxia-inducible factors 1α and 2α (r=0.7 and p&lt;0.001 for both). There were no differences in bone marrow MVD when comparing the different diagnoses. However, the majority of the putative regulators of angiogenesis studied were significantly different between the diagnoses; indicating that bone marrow MVD in hematologic malignancies was differentially regulated. Conclusions: Our data show that patients with hematologic malignancies have increased bone marrow MVD, supporting the notion that bone marrow angiogenesis plays a role in the pathogenesis and progression of these cancers. VEGF, IL-6 and IL-8 seem to contribute to the malignant phenotype.

Dose-Ranging Pharmacodynamic Study of Tipifarnib (R115777) in Patients With Relapsed and Refractory Hematologic Malignancies

2004 ◽  
Vol 22 (23) ◽  
pp. 4816-4822 ◽  
Author(s):  
Todd M. Zimmerman ◽  
Helena Harlin ◽  
Olatoyosi M. Odenike ◽  
Seth Berk ◽  
Evie Sprague ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Peripheral Blood ◽  
Mononuclear Cells ◽  
Bone Marrow Involvement ◽  
Hematologic Malignancies ◽  
Myelogenous Leukemia ◽  
Clinical Activity ◽  
Orally Bioavailable ◽  
Dose Levels ◽  
The Impact

Purpose Tipifarnib, an orally bioavailable inhibitor of farnesyl transferase, has activity in hematologic malignancies, but the dose required to achieve the proposed biologic end point, inhibition of farnesylation, is unknown. Patients and Methods The impact on post-translational farnesylation was assessed in 42 patients with refractory hematologic malignancies and bone marrow involvement. Tipifarnib was taken orally for 21 days of a 28-day cycle. For cycle 1, patients were randomly assigned to one of four dose levels: 100 mg bid, 200 mg bid, 300 mg bid, and 600 mg bid. In cycle 1, peripheral blood and bone marrow mononuclear cells were analyzed for inhibition of HDJ2 prenylation by Western blot analysis at baseline and on day 21. Results Twenty-three patients were assessable for analysis of HDJ2 prenylation before and after therapy. Inhibition of farnesylation was noted at all dose levels, although the highest level of inhibition was noted at the 300-mg-bid dose. The inhibition of farnesylation in the peripheral blood correlated with the inhibition in the bone marrow (r = 0.62). Of the 26 patients assessable for clinical activity after cycle 1, three patients had a significant decrease in total blasts count (acute myeloid leukemia in two patients, and chronic myelogenous leukemia in one patient). The inhibition of farnesylation was greater in the three responders than the nonresponders (P = .03). Conclusion Farnesylation as measured by HDJ2 analysis was inhibited at all dose levels administered. Clinical activity may correlate with the degree of farnesylation inhibition, rather than dose of tipifarnib, and escalation beyond 300 mg bid might not result in additional clinical activity.

Sign in / Sign up

Export Citation Format

Share Document