scholarly journals Restricted Immunoglobulin Joining Chain (IgJ) Protein Expression in B Lymphoblastic Leukemia (B-ALL) Based on B-ALL Subtype

Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 7-7
Author(s):  
Catherine K Gestrich ◽  
Kwadwo Asare Oduro
Keyword(s):  
Gene Expression ◽  
Bone Marrow ◽  
Protein Expression ◽  
Hodgkin Lymphoma ◽  
Predictive Value ◽  
Lymphoblastic Leukemia ◽  
B Cell Lymphoma ◽  
Normal Bone Marrow ◽  
Neoplastic Cells ◽  
Normal Bone

Background Philadelphia-like (Ph-like) B Lymphoblastic Leukemia (B-ALL) is a high-risk subtype of B-ALL that lacks the BCR-ABL1 fusion but has a gene expression profile similar to Philadelphia positive (Ph+) B-ALL. Gene expression profiling has previously identified Immunoglobulin Joining chain (IgJ) overexpression at the mRNA level in Ph-like B-ALL. This is surprising since IgJ is normally expressed by mature or maturing B cells. The normal function of IgJ protein is to concatenate monomers of immunoglobulin IgM or IgA into the mature pentameric and dimeric forms of these molecules respectively. IgJ also plays a crucial role in transport of IgA protein across mucosal epithelium to facilitate mucosal humoral immunity. In hematopathology, J chain immunohistochemistry (IHC) has been used to identify neoplastic cells in nodular lymphocyte predominate Hodgkin lymphoma (NLPHL) and can be used in distinguishing this disease from morphologic mimickers. It does not have known diagnostic utility outside of this context. Lymphoblasts do not typically express immunoglobulins at the protein level. Therefore, we sought to determine the protein expression of IgJ in B-ALL and to determine whether IgJ immunohistochemistry may be employed in identifying particular subtypes of B-ALL. Methods We selected a total of 46 B-ALL cases diagnosed from a bone marrow sample at our institution from 2016-2019 with adequate diagnostic material for IHC. This included 5 cases of Ph-like B-ALL, all with a CRLF2 rearrangement and overexpression, 7 de novo Ph+ B-ALL and 34 cases representing the other most commonly recognized WHO subtypes of B-ALL, determined based on cytogenetic studies performed at the time of diagnosis. No cases of B-ALL with t(5;14) and B-ALL with iAMP21 was represented. Our cohort included 23 pediatric cases and 24 adult cases and the patients ranged from 1 to 82 years old at the time of initial diagnosis. A total of 8 normal bone marrow cases (negative staging bone marrow biopsies for diffuse large B cell lymphoma, neuroblastoma or classic Hodgkin lymphoma) were used as controls. IgJ IHC was performed on B-plus fixed paraffin embedded bone marrow biopsy specimens using a commercially available and validated anti-IgJ monoclonal antibody (clone OTI3B3). Staining of bone marrow samples was performed at 2 different dilutions; tonsil secondary follicles and neoplastic cells from NLPHL were used as technical controls. Cellular staining in the lymphoblasts was scored in a blinded manner by a board certified hematopathologist and a pathologist in training as diffusely positive, partially positive, or negative. Results Cellular staining was distinguishable from background staining due to circulating immunoglobulins and there was almost perfect inter-observer concordance in identifying positive and negative cases (agreement of 98%, kappa test 0.94). All normal bone marrow controls cases were negative for IgJ cellular staining. A total of 11/46 (23%) B-ALL cases demonstrated partial or diffuse cellular staining for IgJ in the lymphoblasts. This included 4/5 (80%) Ph-like cases, 5/7 (71%) Ph+ cases, 1/3 MLL rearranged cases and 1/6 ETV6-RUNX1. All TCF3-PBX1 (0/4), hyperdiploid B-ALL (0/10), hypodiploid B-ALL (0/2), and B-ALL, NOS cases (0/9) were negative for IgJ. Diffuse IgJ staining was restricted to Ph-like (2/4) or Ph+ (2/5) B-ALL subtypes; the positive MLL rearranged and ETV6-RUNX1 B-ALL cases only showed weak partial staining. IgJ protein was significantly expressed in Ph+/Ph-like B-ALL (p<0.0001) and in our cohort, detected these cases with a 75% sensitivity, 95% specificity, 82% positive predictive value and 92% negative predictive value. Conclusion We conclude that IgJ protein expression occurs in a subset of B-ALL, predominantly restricted to Ph+ and Ph-like cases. Although, these findings will need to be validated in larger studies, our results suggest that IgJ IHC, in concert with routine standard cytogenetics studies may be a rapid and cost effective method in identifying Ph-like B-ALL. Disclosures No relevant conflicts of interest to declare.

Role for PP2A Regulatory Subunit B55α as A Regulator of AKT and Other Signaling Pathways In AML.

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 1668-1668
Author(s):  
Peter P. Ruvolo ◽  
YiHua Qui ◽  
Kevin R Coombes ◽  
Nianxiang Zhang ◽  
Vivian Ruvolo ◽  
...  
Keyword(s):  
Gene Expression ◽  
Bone Marrow ◽  
Protein Expression ◽  
Normal Bone Marrow ◽  
Protein Levels ◽  
B Subunit ◽  
Normal Bone ◽  
Cd34 Cells ◽  
Blast Cells ◽  
B Subunits

Abstract Abstract 1668 Activation of survival kinases such as Protein Kinase B (AKT), Protein Kinase C (PKC), and Extracellular Receptor Activated Kinase (ERK) predict poor clinical outcome for patients with acute myeloid leukemia (AML; Kornblau et al Blood 2006). A better understanding of how the activities of these kinases are regulated by phosphorylation and dephosphorylation will enable the development of targeted therapies directed against this axis. Protein Phosphatase 2A (PP2A) negatively regulates PKC, AKT, and ERK but its role in AML is not clear. In the current study we examined the role of PP2A in regulating AKT in AML. Activation of AKT involves phosphorylation of threonine 308 (T308) and serine 473 (S473). A recent study has indicated that phosphorylation of AKT at T308 but not S473 is a poor prognostic factor for AML patients and that PP2A activity negatively correlated with T308 phosphorylation (Gallay et al Leukemia 2009). PP2A is a family of different isoforms that form hetero-trimers consisting of a catalytic C subunit, a scaffold A subunit, and one of at least 21 different regulatory B subunits. The functionality of each PP2A isoform is determined by the regulatory B subunit. Thus to understand PP2A regulation of AKT in AML, it is essential to study the B subunit that regulates the AKT phosphatase. The PP2A isoform regulating AKT in the AML patients is currently unknown. Evidence suggests that the B55a subunit is responsible for dephosphorylation of AKT at T308. In the current study, we compared B55α gene expression in blast cells derived from AML patients with normal counterpart (i.e. CD34+) cells derived from normal bone marrow donors by real time PCR. Surprisingly, B55α gene expression was higher in the patients. Reverse Phase Protein Analysis (RPPA) is a powerful tool that allows for the analysis of protein expression from patient samples. Protein levels of the PP2A B subunit were analyzed by RPPA in AML blast cells obtained from 511 newly diagnosed AML patients and CD34+ cells obtained from 11 normal bone marrow donors. Levels of B55α protein were significantly lower in the blast cells from the AML patients compared to normal CD34+ cells. While the mechanism for the observed difference in gene versus protein expression in the leukemia cells has yet to be determined, a plausible mechanism is that the B55α protein is being proteolyzed since monomeric PP2A B subunits that are not part of the PP2A hetero-trimer are degraded. Importantly the reduced levels of B55α protein observed would be predicted if AKT were activated in the AML blast cells. We next compared AKT phosphorylation status with B55α protein expression in the AML blast cells using RPPA to answer this question. Analysis of RPPA data revealed that there was no correlation between B55α protein levels and levels of total AKT protein or with levels of AKT phosphorylated at S473 in the AML samples. However, there was a moderate but significant negative correlation between B55α protein levels and levels of AKT phosphorylated at T308. This result suggests that B55α is mediating dephosphorylation of AKT at T308 but not S473 in the AML cells. B55α expression was not associated with FAB classification but was positively correlated with high blast and peripheral blood counts. While the level of expression of the B subunit did not correlate with overall survival, intermediate levels of B55α expression were associated with longer complete remission duration. We predict that higher levels of B55α would reflect low levels of other PP2A B subunits. Consistent with this prediction, B55α expression positively correlated with MYC expression in the AML patients. MYC expression is regulated by a B subunit that competes with B55α (i.e. B56α). These findings suggest that B55α may play an important role in AML as a negative regulator of AKT and perhaps by other as yet unidentified functions. Activation of B55α is a potential therapeutic target for overcoming the AKT activation frequently observed in AML. Disclosures: No relevant conflicts of interest to declare.

Gene Expression Profiling Data in Lymphoma and Leukemia: Review of the Literature and Extrapolation of Pertinent Clinical Applications

2006 ◽  
Vol 130 (4) ◽  
pp. 483-520 ◽  
Author(s):  
Cherie H. Dunphy
Keyword(s):  
Gene Expression ◽  
Acute Lymphoblastic Leukemia ◽  
B Cell ◽  
Gene Expression Profiling ◽  
Hodgkin Lymphoma ◽  
Expression Profiling ◽  
Myeloid Leukemia ◽  
Lymphoblastic Leukemia ◽  
B Cell Lymphoma ◽  
Clinical Applications

Abstract Context.—Gene expression (GE) analyses using microarrays have become an important part of biomedical and clinical research in hematolymphoid malignancies. However, the methods are time-consuming and costly for routine clinical practice. Objectives.—To review the literature regarding GE data that may provide important information regarding pathogenesis and that may be extrapolated for use in diagnosing and prognosticating lymphomas and leukemias; to present GE findings in Hodgkin and non-Hodgkin lymphomas, acute leukemias, and chronic myeloid leukemia in detail; and to summarize the practical clinical applications in tables that are referenced throughout the text. Data Source.—PubMed was searched for pertinent literature from 1993 to 2005. Conclusions.—Gene expression profiling of lymphomas and leukemias aids in the diagnosis and prognostication of these diseases. The extrapolation of these findings to more timely, efficient, and cost-effective methods, such as flow cytometry and immunohistochemistry, results in better diagnostic tools to manage the diseases. Flow cytometric and immunohistochemical applications of the information gained from GE profiling assist in the management of chronic lymphocytic leukemia, other low-grade B-cell non-Hodgkin lymphomas and leukemias, diffuse large B-cell lymphoma, nodular lymphocyte–predominant Hodgkin lymphoma, and classic Hodgkin lymphoma. For practical clinical use, GE profiling of precursor B acute lymphoblastic leukemia, precursor T acute lymphoblastic leukemia, and acute myeloid leukemia has supported most of the information that has been obtained by cytogenetic and molecular studies (except for the identification of FLT3 mutations for molecular analysis), but extrapolation of the analyses leaves much to be gained based on the GE profiling data.

scholarly journals Expression of the three myeloid cell-associated immunoglobulin G Fc receptors defined by murine monoclonal antibodies on normal bone marrow and acute leukemia cells

Blood ◽  
1989 ◽  
Vol 73 (7) ◽  
pp. 1951-1956
Author(s):  
ED Ball ◽  
J McDermott ◽  
JD Griffin ◽  
FR Davey ◽  
R Davis ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Monoclonal Antibodies ◽  
Acute Leukemia ◽  
Cell Sorting ◽  
Lymphoblastic Leukemia ◽  
Mononuclear Phagocytes ◽  
Leukemic Cells ◽  
Leukemia Cells ◽  
Normal Bone Marrow ◽  
Normal Bone

Monoclonal antibodies (MoAbs) have been prepared recently that recognize the three cell-surface receptors for the Fc portion of immunoglobulin (Ig), termed Fc gamma RI (MoAb 32.2), Fc gamma R II (MoAb IV-3), and Fc gamma R III (MoAb 3G8) that are expressed on selected subsets of non-T lymphocyte peripheral blood leukocytes. In the blood, Fc gamma R I is expressed exclusively on monocytes and macrophages, Fc gamma R II on granulocytes, mononuclear phagocytes, platelets, and B cells, and Fc gamma R III on granulocytes and natural killer (NK) cells. We have examined the expression of these molecules on normal bone marrow (BM) cells and on leukemia cells from the blood and/or BM in order to determine their normal ontogeny as well as their distribution on leukemic cells. BM was obtained from six normal volunteers and from 170 patients with newly diagnosed acute leukemia. Normal BM cells were found to express Fc gamma R I, II, and III with the following percentages: 40%, 58%, and 56%, respectively. Cell sorting revealed that both Fc gamma R I and Fc gamma R II were detectable on all subclasses of myeloid precursors as early as myeloblasts. Cell sorting experiments revealed that 66% of the granulocyte-monocyte colony-forming cells (CFU-GM) and 50% of erythroid burst-forming units (BFU-E) were Fc gamma R II positive with only 20% and 28%, respectively, of CFU-GM and BFU-E were Fc gamma R I positive. Acute myeloid leukemia (AML) cells expressed the three receptors with the following frequency (n = 146): Fc gamma R I, 58%; Fc gamma R II, 67%; and Fc gamma R III, 26% of patients. Despite the fact that Fc gamma R I is only expressed on monocytes among blood cells, AML cells without monocytoid differentiation (French-American-British [FAB]M1, M2, M3, M6) were sometimes positive for this receptor. However, Fc gamma R I was highly correlated with FAB M4 and M5 morphology (P less than .001). Fc gamma R II was also correlated with FAB M4 and M5 morphology (P = .003). Cells from 11 patients with acute lymphoblastic leukemia were negative for Fc gamma R I, but six cases were positive for Fc gamma R II and III (not the same patients). These studies demonstrate that Ig Fc gamma R are acquired during normal differentiation in the BM at or before the level of colony-forming units. In addition, we show that acute leukemia cells commonly express Fc gamma R.

The classification of leukaemia

2010 ◽  
pp. 4221-4228
Author(s):  
Wendy N. Erber
Keyword(s):  
Bone Marrow ◽  
Characteristic Feature ◽  
Lymph Nodes ◽  
Malignant Neoplasm ◽  
Normal Bone Marrow ◽  
Neoplastic Cells ◽  
Normal Bone ◽  
Haematopoietic Cells ◽  
Leukaemic Cells

Leukaemia is a malignant neoplasm of haematopoietic cells originating in the marrow and spreading to the blood and other tissues, such as the lymph nodes, spleen, and liver. The characteristic feature of the neoplastic cells is that they retain the ability to proliferate but fail to differentiate normally into functional haematopoietic cells. This results in replacement of the normal bone marrow by the leukaemic cells....

scholarly journals Expression of the three myeloid cell-associated immunoglobulin G Fc receptors defined by murine monoclonal antibodies on normal bone marrow and acute leukemia cells

Blood ◽  
1989 ◽  
Vol 73 (7) ◽  
pp. 1951-1956 ◽  
Author(s):  
ED Ball ◽  
J McDermott ◽  
JD Griffin ◽  
FR Davey ◽  
R Davis ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Monoclonal Antibodies ◽  
Acute Leukemia ◽  
Cell Sorting ◽  
Lymphoblastic Leukemia ◽  
Mononuclear Phagocytes ◽  
Leukemic Cells ◽  
Leukemia Cells ◽  
Normal Bone Marrow ◽  
Normal Bone

Abstract Monoclonal antibodies (MoAbs) have been prepared recently that recognize the three cell-surface receptors for the Fc portion of immunoglobulin (Ig), termed Fc gamma RI (MoAb 32.2), Fc gamma R II (MoAb IV-3), and Fc gamma R III (MoAb 3G8) that are expressed on selected subsets of non-T lymphocyte peripheral blood leukocytes. In the blood, Fc gamma R I is expressed exclusively on monocytes and macrophages, Fc gamma R II on granulocytes, mononuclear phagocytes, platelets, and B cells, and Fc gamma R III on granulocytes and natural killer (NK) cells. We have examined the expression of these molecules on normal bone marrow (BM) cells and on leukemia cells from the blood and/or BM in order to determine their normal ontogeny as well as their distribution on leukemic cells. BM was obtained from six normal volunteers and from 170 patients with newly diagnosed acute leukemia. Normal BM cells were found to express Fc gamma R I, II, and III with the following percentages: 40%, 58%, and 56%, respectively. Cell sorting revealed that both Fc gamma R I and Fc gamma R II were detectable on all subclasses of myeloid precursors as early as myeloblasts. Cell sorting experiments revealed that 66% of the granulocyte-monocyte colony-forming cells (CFU-GM) and 50% of erythroid burst-forming units (BFU-E) were Fc gamma R II positive with only 20% and 28%, respectively, of CFU-GM and BFU-E were Fc gamma R I positive. Acute myeloid leukemia (AML) cells expressed the three receptors with the following frequency (n = 146): Fc gamma R I, 58%; Fc gamma R II, 67%; and Fc gamma R III, 26% of patients. Despite the fact that Fc gamma R I is only expressed on monocytes among blood cells, AML cells without monocytoid differentiation (French-American-British [FAB]M1, M2, M3, M6) were sometimes positive for this receptor. However, Fc gamma R I was highly correlated with FAB M4 and M5 morphology (P less than .001). Fc gamma R II was also correlated with FAB M4 and M5 morphology (P = .003). Cells from 11 patients with acute lymphoblastic leukemia were negative for Fc gamma R I, but six cases were positive for Fc gamma R II and III (not the same patients). These studies demonstrate that Ig Fc gamma R are acquired during normal differentiation in the BM at or before the level of colony-forming units. In addition, we show that acute leukemia cells commonly express Fc gamma R.

Nucleostemin Gene Expression in Acute Promyelocytic Leukemia Patients.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 4430-4430
Author(s):  
Farzaneh Ashrafi ◽  
Fatemeh Nadali ◽  
Ardeshir Ghavamzadeh ◽  
Kamran Alimoghaddam ◽  
Shahrbano Rostami ◽  
...  
Keyword(s):  
Gene Expression ◽  
Stem Cells ◽  
Bone Marrow ◽  
Acute Promyelocytic Leukemia ◽  
Promyelocytic Leukemia ◽  
Normal Bone Marrow ◽  
Newly Diagnosed ◽  
Normal Bone ◽  
Ns Gene ◽  
Significant Difference

Abstract Abstract 4430 Background Nucleostemin (NS), a novel p53-binding protein has been shown essential for stem and cancer cell proliferation and implicated in oncogenesis. Nucleostemin expression had been shown in gastric cancer (SGC-7901) cells, human hepatocarcinoma (HepG2) cells, human cervical cancer (Hela) cells, human osteosarcoma (OS-732) cells. Aim This work designed to study the NS gene expression in bone marrow cells in acute promyelocytic leukemia (APL) patients and in normal bone marrow specimens. Materials &Methods We examined NS gene expression by Quantitative Real Time PCR in bone marrow specimens of 15 cases of APL patients, before treatment and in 4 bone marrow specimens of healthy donors of bone marrow transplantation. In the same samples of bone marrow aspiration morphology of smears was evaluated. Diagnosis of APL was based on morphology and positive PML/RARA in PCR. RT-PCR used to amplify the NS mRNA, and the GAPDH primer sets used for normalizing. For comparison of NS gene expreesion in 2 groups Mann-Whitney U test was used. Results 15 patients enrolled in this study, 11(73%) newly diagnosed APL and 4(27%) relapsed cases. Mean age of patients was 28.67±9.56 year. NS gene expressed in all bone marrow samples of APL patients. NS gene expressed in normal bone marrow specimens too. NS gene expression in bone marrow of APL patients was significantly higher than normal bone marrows(p value =0.002) Fig 1. There was no significant difference in NS gene expression between newly diagnosed and relapsed APL cases. Discussion According to the results of this study it seems that NS gene expressed in normal marrow. NS expression in adult bone marrow hematopoietic stem cells had been reported in previous reports and it had been shown that NS does not express in granulocytes and B lymphocytes. It seems that stem cells and proliferating cells in the normal marrow are the source of NS expression detected in normal marrow. NS expreesion in bone marrow of APL patients was significantly higher than normal marrow. In these patients before treatment marrow is replaced by undifferentiated blasts and promyelocytes. We concluded that NS expression in these cells were high. It had been shown that NS down regulation may lead to cell cycle exit. High expression of NS in APL patients can be used in future researches for finding new targeted therapies in this disease. Disclosures: No relevant conflicts of interest to declare.

Gene expression in CD34+ cells from normal bone marrow and leukemic origins

2000 ◽  
Vol 1 (3) ◽  
pp. 206-217 ◽  
Author(s):  
Jian Gu ◽  
Qing-Hua Zhang ◽  
Qiu-Hua Huang ◽  
Shuang-Xi Ren ◽  
Xin-Yan Wu ◽  
...  
Keyword(s):  
Gene Expression ◽  
Bone Marrow ◽  
Normal Bone Marrow ◽  
Normal Bone ◽  
Cd34 Cells

Characterization of Mesenchymal Stromal Cells (MSCs) Derived From Acute Myeloid Leukemia (AML) Bone Marrow

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 2558-2558
Author(s):  
Soumit K. Basu ◽  
Xin Zhao ◽  
Sylvia Chien ◽  
Min Fang ◽  
Vivian Oehler ◽  
...  
Keyword(s):  
Gene Expression ◽  
Bone Marrow ◽  
Gene Expression Profiling ◽  
Expression Profiling ◽  
Stromal Cell ◽  
Collagen Type ◽  
Β1 Integrin ◽  
Normal Bone Marrow ◽  
Bone Marrow Mscs ◽  
Normal Bone

Abstract Abstract 2558 INTRODUCTION Recent evidence has implicated the bone marrow microenvironment directly in the pathogenesis of preleukemic bone marrow disorders (Raaijmakers MHGP et al, Nature 2010) with potential to transform to AML. Moreover, the bone marrow microenvironment is critical to AML survival (Garrido et al 2001, Meads et al 2008). We sought to investigate aspects of the bone marrow microenvironment which may contribute to the pathogenesis and persistence of AML by direct analysis of primary bone marrow MSCs isolated from AML patients in comparison with primary bone marrow MSCs from normal subjects. Our analyses included (1) a comparison of cytokine elaboration between normal and AML bone marrow MSCs (2) immunophenotyping of normal and AML bone marrow MSCs (3) characterisation of binding by AML cells to their autologous stroma and (4) gene expression profiling of normal and AML bone marrow MSCs and (5) cytogenetic analysis AML bone marrow MSCs. METHODS We have been able to derive confluent cultures of mesenchymal stromal cells from 80% of AML patient marrow samples. Fresh or cryopreserved bone marrow samples were plated in non-hematopoietic expansion media (Miltenyi) under reduced oxygen conditions. After 48 hours of culture, nonadherent cells are removed, and over a period of 1–2 weeks, cultures of spindle shaped cells are derived, that can be sustained in culture for up to 5 passages. Similar cultures were derived from normal bone marrow. Gene expression profiling of bone marrow MSCs was performed by whole genome analysis using Illumina's BeadChip microarray platform. Samples included mRNAs isolated from confluent cultures of AML bone marrow MSCs, normal bone marrow MSCs, and the normal bone marrow stromal cell lines HS27a and HS5. RESULTS Comparison of cytokine elaboration showed a statistically significant (p = 0.037) 5-fold decrease in stromal MCP-1 production by AML bone marrow MSCs compared with normal bone marrow MSCs (327 ± 169 vs. 1669 ± 570 pg/mL, mean ± SE). Normal and AML MSCs showed no statistically significant differences in the production of G-CSF, GM-CSF, M-CSF, IL6, IL12, SCF, TNFα, MCP1 and SDF1β. Like their normal counterparts, AML bone marrow MSCs strongly express CD90, CD29 (β1 integrin), CD73, CD105, CD146, and CD44. The normal bone marrow derived stromal cell lines HS27a and HS5 demonstrated moderate expression of CD324/E-cadherin (28.4% and 37.9% respectively). E-cadherin expression proved highly variable among normal bone marrow MSCs (1.9%-54.9%) and similarly variable in AML bone marrow MSCs (7.8%–56.5%). AML binding to autologous MSCs primarily dependent on β1 integrin, L-selectin and VCAM-1. In contrast, prior data (Basu et al., ASH 2010 Abstract 2756) demonstrated AML binding to the normal bone marrow stromal cell line HS27a as primarily dependent on β1 integrin, CXCR4, and E-cadherin. Gene expression profiling demonstrated no significant differences between 6 AML and 5 normal bone marrow MSCs. AML bone marrow MSCs, as expected, demonstrated marked differences from AML bone marrow mononuclear cells, expressing higher levels of connective tissue growth factor (128 fold), tropomyosin 1 (84.4 fold), collagen type 1 α1 (194 fold), collagen type 1 α2 (137 fold), collagen type 4 α1 (128 fold), collagen type 5 α1 (119 fold), transgelin (111 fold), cadherin 11 (21 fold), biglycan (137 fold), IGF binding protein 6 (18 fold), and procollagen-lysine 2-oxoglutarate 5-dioxygenase 2 (74 fold). In our cytogenetic analyses of MSCs to date, bone marrow MSCs derived from one of the complex karyotype AML patients demonstrated normal cytogenetics. In contrast, bone marrow MSCs derived from a second AML patient shared a common t(2;11) translocation present in the AML cells but demonstrated an abnormal clone with del(4q) which lacked the t(6;9) also present in the AML cells [i.e.-MSC karyotype: t(2;11), del(4q); AML karyotype: t(2;11), t(6;9)]. These results suggest that in some patients AML cells and their autologous MSCs may share the same clonal origin, while in other cases, the MSCs may have a distinct origin. CONCLUSION AML and normal bone marrow MSCs demonstrate only subtle differences, providing an explanation of the ability of AML bone marrow MSCs to support normal hematopoiesis after leukemic debulking (e.g. via induction chemotherapy or allogeneic stem cell transplant). Disclosures: No relevant conflicts of interest to declare.

The Proliferation Inhibitor CDKN1C (P57KIP2) Is Over Expressed in CD34+ Cells of Patients with MDS and Determines a Worse Prognosis Independently of IPSS Score Factors

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 3820-3820
Author(s):  
Sascha Dietrich ◽  
Mindaugas Andrulis ◽  
Andrea Pellagatti ◽  
Aleksandar Radujkovic ◽  
Ulrich Germing ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Overall Survival ◽  
Protein Expression ◽  
Normal Bone Marrow ◽  
Double Staining ◽  
Expression Levels ◽  
Cyclin Dependent Kinases ◽  
Normal Bone ◽  
Cd34 Cells ◽  
Worse Prognosis

Abstract Abstract 3820 Purpose: Progressive cytopenias are the cause of death for the majority of patients with myelodysplastic syndromes (MDS). In order to investigate if the proliferative activity of CD34+ cells in MDS bone marrow correlates with prognosis, we measured expression levels of the proliferation inhibitor CDKN1C (P57KIP2) in two independent study cohorts. Patients and methods: Gene expression profiling data on bone marrow CD34+ cells were obtained from 183 MDS patients (55 with RA, 48 with RARS, 37 with RAEB1 and 43 with RAEB2). mRNA expression levels of CDKN1C (P57KIP2) were correlated with overall survival (OS) and proliferation markers such as PCNA, cyclins and cyclin dependent kinases. In a second independent patient cohort comprising 93 patients (17 had RA, 13 REAB1, 27 RAEB2, 29 AML arising from MDS and 7 CMML), protein expression levels of CDKN1C (P57KIP2) were evaluated by immune histochemistry (IHC) in trephine biopsies. Protein expression levels of CDKN1C (P57KIP2) were correlated with clinical outcome, OS and the proliferation marker KI67 in CD34+ cells (double staining). Results: In purified CD34+ cells, mRNA expression of CDKN1C (P57KIP2) correlated with higher risk and poorer overall survival of patients with MDS (p=0.0006, n=183, Figure1). Furthermore, increased CDKN1C (P57KIP2) expression was significantly associated with loss of CD38 (p=0.002) as well as loss of proliferating cell nuclear antigen (PCNA, p<0.001), cyclins and cyclin-dependent kinases (p<0.001) underlining the role of CDKN1C (P57KIP2) as a proliferation inhibitor. Similarly, protein expression of CDKN1C (P57KIP2) determined in trephine biopsies predicted a poor prognosis of patients with MDS (p=0.0003, HR=2.2, n=93, Figure 1). No expression of CDKN1C (P57KIP2) could be demonstrated in 10 control patients with normal bone marrow. Separate evaluation of WHO risk categories revealed that in patients with less than 10% blasts (RA, RAEB1 and CMML1), CDKN1C (P57KIP2) was not predictive for OS. In contrast, patients with high CDKN1C (P57KIP2) expression and RAEB2 (p=.0.02, HR 2.4) or AML arising from MDS (p=0.002, HR 2.9) had a significantly worse OS than patients with low CDKN1C (P57KIP2) levels. CDKN1C (P57KIP2) expression analysis within the group of allogeneic stem cell recipients showed no impact on survival after transplant. Multivariate cox regression analysis with the confounding co-variates: age, IPSS score factors (cytopenias, cytogenetic risk profile, blast count) and primary versus secondary MDS confirmed the independent impact of CDKN1C (P57KIP2) expression on OS (p=0.0002, HR 2.9). CDKN1C (P57KIP2) protein expression could also be demonstrated in sorted CD34+ cells of MDS patients by western blot analysis and was significantly higher than in CD34- cells (p=0.03, n=7). KI67 expression was evaluated in CD34+ cells by IHC double staining in 34 trephine biopsies and 10 control patients with normal bone marrow. Percentages of CD34+ and KI67 positive cells were higher in control patients and patients with low risk MDS (RA, RAEB1) than in patients with high risk MDS (RAEB2) (p<0.01). Patients with AML (>20% blasts) had significantly higher levels of KI67 (p<0.05). In patients with MDS (<20% blasts) KI67 percentages correlated inversely with CDKN1C (P57KIP2) expression (p=0.04). Conclusions: High CDKN1C (P57KIP2) expression in CD34+ cells of patients with MDS is associated with a reduced fraction of proliferative CD34+ cells and determines a worse prognosis independently of factors used to calculate the IPSS score. Allogeneic stem cell transplantation could overcome the worse prognosis of high CDKN1C (P57KIP2) expression. Further studies are warranted to determine the impact of CDKN1C (P57KIP2) expression to guide clinical decisions. Disclosures: No relevant conflicts of interest to declare.

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