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3.  Novel drug candidates for blast phase chronic myeloid leukemia from high-throughput drug sensitivity and resistance testing 
Blood Cancer Journal  2015;5(5):e309-.
Chronic myeloid leukemia in blast crisis (CML BC) remains a challenging disease to treat despite the introduction and advances in tyrosine kinase inhibitor (TKI) therapy. In this study we set out to identify novel candidate drugs for CML BC by using an unbiased high-throughput drug testing platform. We used three CML cell lines representing different types of CML blast phases (K562, EM-2 and MOLM-1) and primary leukemic cells from three CML BC patients. Profiling of drug responses was performed with a drug sensitivity and resistance testing platform comprising 295 anticancer agents. Overall, drug sensitivity scores and the drug response profiles of cell line and primary cell samples correlated well and were distinct from other types of leukemia samples. The cell lines were highly sensitive to TKIs and the clinically TKI-resistant patient samples were also resistant ex vivo. Comparison of cell line and patient sample data identified new candidate drugs for CML BC, such as vascular endothelial growth factor receptor and nicotinamide phosphoribosyltransferase inhibitors. Our results indicate that these drugs in particular warrant further evaluation by analyzing a larger set of primary patient samples. The results also pave way for designing rational combination therapies.
PMCID: PMC4423219  PMID: 25933373
4.  Abnormal FISH in patients with immunoglobulin light chain amyloidosis is a risk factor for cardiac involvement and for death 
Blood Cancer Journal  2015;5(5):e310-.
Importance of interphase fluorescent in situ hybridization (FISH) with cytoplasmic staining of immunoglobulin FISH (cIg-FISH) on bone marrow is not well understood in light chain amyloidosis (AL). This is in contrast with multiple myeloma where prognostic and treatment related decisions are dependent on cytogenetic testing. This retrospective study reviewed 401 AL patients with cIg-FISH testing performed at our institution between 2004 and 2012. Eighty-one percent of patients had an abnormal cIg-FISH. Common abnormalities involved translocations of chromosome 14q32 (52%), specifically: t(11;14) (43%), t(14;16) (3%) and t(4;14) (2%). Other common abnormalities include monosomy 13/deletion 13q (30%), trisomies 9 (20%), 15 (14%), 11 (10%) and 3 (10%). Median overall survival for this cohort of patients is 3.5 years. When plasma cell burden was greater than 10% trisomies predicted for worse survival (44 vs 19 months), and when it was ⩽10% t(11;14) predicted for worse survival (53 months vs not reached). Abnormal cIg-FISH was significantly associated with advanced cardiac involvement, and remained a prognostic factor on multivariate analysis. This large AL cohort demonstrates that abnormal FISH at diagnosis is prognostic for survival and advanced cardiac disease. Particularly, trisomies and t(11;14) affect survival when degree of plasma cell burden is considered.
PMCID: PMC4423220  PMID: 25933374
5.  NPM-ALK mediates phosphorylation of MSH2 at tyrosine 238, creating a functional deficiency in MSH2 and the loss of mismatch repair 
Blood Cancer Journal  2015;5(5):e311-.
The vast majority of anaplastic lymphoma kinase-positive anaplastic large cell lymphoma (ALK+ALCL) tumors express the characteristic oncogenic fusion protein NPM-ALK, which mediates tumorigenesis by exerting its constitutive tyrosine kinase activity on various substrates. We recently identified MSH2, a protein central to DNA mismatch repair (MMR), as a novel binding partner and phosphorylation substrate of NPM-ALK. Here, using liquid chromatography–mass spectrometry, we report for the first time that MSH2 is phosphorylated by NPM-ALK at a specific residue, tyrosine 238. Using GP293 cells transfected with NPM-ALK, we confirmed that the MSH2Y238F mutant is not tyrosine phosphorylated. Furthermore, transfection of MSH2Y238F into these cells substantially decreased the tyrosine phosphorylation of endogenous MSH2. Importantly, gene transfection of MSH2Y238F abrogated the binding of NPM-ALK with endogenous MSH2, re-established the dimerization of MSH2:MSH6 and restored the sensitivity to DNA mismatch-inducing drugs, indicative of MMR return. Parallel findings were observed in two ALK+ALCL cell lines, Karpas 299 and SUP-M2. In addition, we found that enforced expression of MSH2Y238F into ALK+ALCL cells alone was sufficient to induce spontaneous apoptosis. In conclusion, our findings have identified NPM-ALK-induced phosphorylation of MSH2 at Y238 as a crucial event in suppressing MMR. Our studies have provided novel insights into the mechanism by which oncogenic tyrosine kinases disrupt MMR.
PMCID: PMC4476014  PMID: 25978431
7.  The SUV39H1 inhibitor chaetocin induces differentiation and shows synergistic cytotoxicity with other epigenetic drugs in acute myeloid leukemia cells 
Blood Cancer Journal  2015;5(5):e313-.
Epigenetic modifying enzymes have a crucial role in the pathogenesis of acute myeloid leukemia (AML). Methylation of lysine 9 on histone H3 by the methyltransferase G9a and SUV39H1 is associated with inhibition of tumor suppressor genes. We studied the effect of G9a and SUV39H1 inhibitors on viability and differentiation of AML cells and tested the cytotoxicity induced by combination of G9a and SUV39H1 inhibitors and various epigenetic drugs. The SUV39H1 inhibitor (chaetocin) and the G9a inhibitor (UNC0638) caused cell death in AML cells at high concentrations. However, only chaetocin-induced CD11b expression and differentiation of AML cells at non-cytotoxic concentration. HL-60 and KG-1a cells were more sensitive to chaetocin than U937 cells. Long-term incubation of chaetocin led to downregulation of SUV39H1 and reduction of H3K9 tri-methylation in HL-60 and KG-1a cells. Combination of chaetocin with suberoylanilide hydroxamic acid (SAHA, a histone deacetylase inhibitor) or JQ (a BET (bromodomain extra terminal) bromodomain inhibitor) showed synergistic cytotoxicity. Conversely, no synergism was found by combining chaetocin and UNC0638. More importantly, chaetocin-induced differentiation and combined cytotoxicity were also found in the primary cells of AML patients. Collectively, the SUV39H1 inhibitor chaetocin alone or in combination with other epigenetic drugs may be effective for the treatment of AML.
PMCID: PMC4476016  PMID: 25978433
8.  Rational combination treatment with histone deacetylase inhibitors and immunomodulatory drugs in multiple myeloma 
Blood Cancer Journal  2015;5(5):e312-.
Immunomodulatory drugs (IMiDs) thalidomide, lenalidomide (Len) and pomalidomide trigger anti-tumor activities in multiple myeloma (MM) by targetting cereblon and thereby impacting IZF1/3, c-Myc and IRF4. Histone deacetylase inhibitors (HDACi) also downregulate c-Myc. We therefore determined whether IMiDs with HDACi trigger significant MM cell growth inhibition by inhibiting or downregulating c-Myc. Combination treatment of Len with non-selective HDACi suberoylanilide hydroxamic acid or class-I HDAC-selective inhibitor MS275 induces synergic cytotoxicity, associated with downregulation of c-Myc. Unexpectedly, we observed that decreased levels of cereblon (CRBN), a primary target protein of IMiDs, was triggered by these agents. Indeed, sequential treatment of MM cells with MS275 followed by Len shows less efficacy than simultaneous treatment with this combination. Importantly ACY1215, an HDAC6 inhibitor with minimal effects on class-I HDACs, together with Len induces synergistic MM cytotoxicity without alteration of CRBN expression. Our results showed that only modest class-I HDAC inhibition is able to induce synergistic MM cytotoxicity in combination with Len. These studies may provide the framework for utilizing HDACi in combination with Len to both avoid CRBN downregulation and enhance anti-MM activities.
PMCID: PMC4476017  PMID: 25978432
9.  A novel antibody–drug conjugate targeting SAIL for the treatment of hematologic malignancies 
Blood Cancer Journal  2015;5(5):e316-.
Although several new therapeutic approaches have improved outcomes in the treatment of hematologic malignancies, unmet need persists in acute myeloid leukemia (AML), multiple myeloma (MM) and non-Hodgkin's lymphoma. Here we describe the proteomic identification of a novel cancer target, SAIL (Surface Antigen In Leukemia), whose expression is observed in AML, MM, chronic lymphocytic leukemia (CLL), diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma (FL). While SAIL is widely expressed in CLL, AML, MM, DLBCL and FL patient samples, expression in cancer cell lines is mostly limited to cells of AML origin. We evaluated the antitumor activity of anti-SAIL monoclonal antibodies, 7-1C and 67-7A, conjugated to monomethyl auristatin F. Following internalization, anti-SAIL antibody–drug conjugates (ADCs) exhibited subnanomolar IC50 values against AML cell lines in vitro. In pharmacology studies employing AML cell line xenografts, anti-SAIL ADCs resulted in significant tumor growth inhibition. The restricted expression profile of this target in normal tissues, the high prevalence in different types of hematologic cancers and the observed preclinical activity support the clinical development of SAIL-targeted ADCs.
PMCID: PMC4476018  PMID: 26024286
12.  Genetic and epigenetic profiling of CLL disease progression reveals limited somatic evolution and suggests a relationship to memory-cell development 
Blood Cancer Journal  2015;5(4):e303-.
We examined genetic and epigenetic changes that occur during disease progression from indolent to aggressive forms of chronic lymphocytic leukemia (CLL) using serial samples from 27 patients. Analysis of DNA mutations grouped the leukemia cases into three categories: evolving (26%), expanding (26%) and static (47%). Thus, approximately three-quarters of the CLL cases had little to no genetic subclonal evolution. However, we identified significant recurrent DNA methylation changes during progression at 4752 CpGs enriched for regions near Polycomb 2 repressive complex (PRC2) targets. Progression-associated CpGs near the PRC2 targets undergo methylation changes in the same direction during disease progression as during normal development from naive to memory B cells. Our study shows that CLL progression does not typically occur via subclonal evolution, but that certain CpG sites undergo recurrent methylation changes. Our results suggest CLL progression may involve developmental processes shared in common with the generation of normal memory B cells.
PMCID: PMC4450323  PMID: 25860294
13.  Mesenchymal stromal cells derived from acute myeloid leukemia bone marrow exhibit aberrant cytogenetics and cytokine elaboration 
Blood Cancer Journal  2015;5(4):e302-.
Bone marrow-derived mesenchymal stromal cells (BM-MSCs) play a fundamental role in the BM microenvironment (BME) and abnormalities of these cells may contribute to acute myeloid leukemia (AML) pathogenesis. The aim of the study was to characterize the cytokine and gene expression profile, immunophenotype and cytogenetics of BM-MSCs from AML patients compared to normal BM-MSCs from healthy donors. AML BM-MSCs showed decreased monocyte chemoattractant protein-1 levels compared to normal BM-MSCs. AML BM-MSCs expressed similar β1 integrin, CD44, CD73, CD90 and E-cadherin compared to normal BM-MSCs. Cytogenetic analysis revealed chromosomal aberrations in AML BM-MSCs, some overlapping with and others distinct from their corresponding AML blasts. No significant difference in gene expression was detected between AML BM-MSCs compared to normal BM-MSCs; however, comparing the differences between AML and MSCs from AML patients with the differences between normal hematopoietic cells and normal MSCs by Ingenuity pathway analysis showed key distinctions of the AML setting: (1) upstream gene regulation by transforming growth factor beta 1, tumor necrosis factor, tissue transglutaminase 2, CCAAT/enhancer binding protein alpha and SWItch/Sucrose NonFermentable related, matrix associated, actin dependent regulator of chromatin, subfamily a, member 4; (2) integrin and interleukin 8 signaling as overrepresented canonical pathways; and (3) upregulation of transcription factors FBJ murine osteosarcoma viral oncogene homolog and v-myb avian myeloblastosis viral oncogene homolog. Thus, phenotypic abnormalities of AML BM-MSCs highlight a dysfunctional BME that may impact AML survival and proliferation.
PMCID: PMC4450324  PMID: 25860293
14.  Acute promyelocytic leukemia: where did we start, where are we now, and the future 
Blood Cancer Journal  2015;5(4):e304-.
Historically, acute promyelocytic leukemia (APL) was considered to be one of the most fatal forms of acute leukemia with poor outcomes before the introduction of the vitamin A derivative all-trans retinoic acid (ATRA). With considerable advances in therapy, including the introduction of ATRA initially as a single agent and then in combination with anthracyclines, and more recently by development of arsenic trioxide (ATO)-containing regimens, APL is now characterized by complete remission rates of 90% and cure rates of ∼80%, even higher among low-risk patients. Furthermore, with ATRA–ATO combinations, chemotherapy may safely be omitted in low-risk patients. The disease is now considered to be the most curable subtype of acute myeloid leukemia (AML) in adults. Nevertheless, APL remains associated with a significant incidence of early death related to the characteristic bleeding diathesis. Early death, rather than resistant disease so common in all other subtypes of AML, has emerged as the major cause of treatment failure.
PMCID: PMC4450325  PMID: 25885425
17.  Haematological cancer and quality of life: a systematic literature review 
Blood Cancer Journal  2015;5(4):e305-.
The aim of this study is to examine the impact of haematological cancers on quality of life (QoL). A review of the international literature was conducted from the databases ‘PsycInfo' and 'Medline' using the keywords: 'haematological cancer', 'quality of life', 'physical', 'psychological', 'social', 'vocational', 'professional', 'economic', 'cognitive', and 'sexual'. Twenty-one reliable studies were analysed. Among these studies, 12 showed that haematological cancer altered overall QoL, 8 papers found a deterioration of physical dimension, 8 papers reported on functional and role dimensions, 11 papers reported on the psychological component and 9 on the social component. Moreover, one study and two manuscripts, respectively, reported deteriorated sexual and cognitive dimensions. Our review demonstrates that the different dimensions of QoL are deteriorated by haematological malignancies and, probably, by the side effects of treatment.
PMCID: PMC4450328  PMID: 25909835
18.  Drug screen in patient cells suggests quinacrine to be repositioned for treatment of acute myeloid leukemia 
Blood Cancer Journal  2015;5(4):e307-.
To find drugs suitable for repositioning for use against leukemia, samples from patients with chronic lymphocytic, acute myeloid and lymphocytic leukemias as well as peripheral blood mononuclear cells (PBMC) were tested in response to 1266 compounds from the LOPAC1280 library (Sigma). Twenty-five compounds were defined as hits with activity in all leukemia subgroups (<50% cell survival compared with control) at 10 μM drug concentration. Only one of these compounds, quinacrine, showed low activity in normal PBMCs and was therefore selected for further preclinical evaluation. Mining the NCI-60 and the NextBio databases demonstrated leukemia sensitivity and the ability of quinacrine to reverse myeloid leukemia gene expression. Mechanistic exploration was performed using the NextBio bioinformatic software using gene expression analysis of drug exposed acute myeloid leukemia cultures (HL-60) in the database. Analysis of gene enrichment and drug correlations revealed strong connections to ribosomal biogenesis nucleoli and translation initiation. The highest drug–drug correlation was to ellipticine, a known RNA polymerase I inhibitor. These results were validated by additional gene expression analysis performed in-house. Quinacrine induced early inhibition of protein synthesis supporting these predictions. The results suggest that quinacrine have repositioning potential for treatment of acute myeloid leukemia by targeting of ribosomal biogenesis.
PMCID: PMC4450329  PMID: 25885427
19.  The cellular immune system in myelomagenesis: NK cells and T cells in the development of MM and their uses in immunotherapies 
Blood Cancer Journal  2015;5(4):e306-.
As vast strides are being made in the management and treatment of multiple myeloma (MM), recent interests are increasingly focusing on understanding the development of the disease. The knowledge that MM develops exclusively from a protracted phase of monoclonal gammopathy of undetermined significance provides an opportunity to study tumor evolution in this process. Although the immune system has been implicated in the development of MM, the scientific literature on the role and status of various immune components in this process is broad and sometimes contradictory. Accordingly, we present a review of cellular immune subsets in myelomagenesis. We summarize the current literature on the quantitative and functional profiles of natural killer cells and T-cells, including conventional T-cells, natural killer T-cells, γδ T-cells and regulatory T-cells, in myelomagenesis. Our goal is to provide an overview of the status and function of these immune cells in both the peripheral blood and the bone marrow during myelomagenesis. This provides a better understanding of the nature of the immune system in tumor evolution, the knowledge of which is especially significant considering that immunotherapies are increasingly being explored in the treatment of both MM and its precursor conditions.
PMCID: PMC4450330  PMID: 25885426
21.  Dysregulated choline metabolism in T-cell lymphoma: role of choline kinase-α and therapeutic targeting 
Blood Cancer Journal  2015;5(3):287-.
Cancer cells have distinct metabolomic profile. Metabolic enzymes regulate key oncogenic signaling pathways and have an essential role on tumor progression. Here, serum metabolomic analysis was performed in 45 patients with T-cell lymphoma (TCL) and 50 healthy volunteers. The results showed that dysregulation of choline metabolism occurred in TCL and was related to tumor cell overexpression of choline kinase-α (Chokα). In T-lymphoma cells, pharmacological and molecular silencing of Chokα significantly decreased Ras-GTP activity, AKT and ERK phosphorylation and MYC oncoprotein expression, leading to restoration of choline metabolites and induction of tumor cell apoptosis/necropotosis. In a T-lymphoma xenograft murine model, Chokα inhibitor CK37 remarkably retarded tumor growth, suppressed Ras-AKT/ERK signaling, increased lysophosphatidylcholine levels and induced in situ cell apoptosis/necropotosis. Collectively, as a regulatory gene of aberrant choline metabolism, Chokα possessed oncogenic activity and could be a potential therapeutic target in TCL, as well as other hematological malignancies with interrupted Ras signaling pathways.
PMCID: PMC4382653  PMID: 25768400
22.  The relationship of TP53 R72P polymorphism to disease outcome and TP53 mutation in myelodysplastic syndromes 
Blood Cancer Journal  2015;5(3):e291-.
Nonsynonymous TP53 exon 4 single-nucleotide polymorphism (SNP), R72P, is linked to cancer and mutagen susceptibility. R72P associations with specific cancer risk, particularly hematological malignancies, have been conflicting. Myelodysplastic syndrome (MDS) with chromosome 5q deletion is characterized by erythroid hypoplasia arising from lineage-specific p53 accumulation resulting from ribosomal insufficiency. We hypothesized that apoptotically diminished R72P C-allele may influence predisposition to del(5q) MDS. Bone marrow and blood DNA was sequenced from 705 MDS cases (333 del(5q), 372 non-del(5q)) and 157 controls. Genotype distribution did not significantly differ between del(5q) cases (12.6% CC, 38.1% CG, 49.2% GG), non-del(5q) cases (9.7% CC, 44.6% CG, 45.7% GG) and controls (7.6% CC, 37.6% CG, 54.8% GG) (P=0.13). Allele frequency did not differ between non-del(5q) and del(5q) cases (P=0.91) but trended towards increased C-allele frequency comparing non-del(5q) (P=0.08) and del(5q) (P=0.10) cases with controls. Median lenalidomide response duration increased proportionate to C-allele dosage in del(5q) patients (2.2 (CC), 1.3 (CG) and 0.89 years (GG)). Furthermore, C-allele homozygosity in del(5q) was associated with prolonged overall and progression-free survival and non-terminal interstitial deletions that excluded 5q34, whereas G-allele homozygozity was associated with inferior outcome and terminal deletions involving 5q34 (P=0.05). These findings comprise the largest MDS R72P SNP analysis.
PMCID: PMC4382654  PMID: 25768405
25.  Transmission of psoriasis by allogeneic bone marrow transplantation and blood transfusion 
Li, X | Li, J | Wang, L | Niu, X | Hou, R | Liu, R | Hao, Z | Wang, C | Yin, G | Zhang, K
Blood Cancer Journal  2015;5(3):e288-.
PMCID: PMC4382657  PMID: 25768402

Résultats 1-25 (309)