High CD74 expression correlates with ZAP70 expression in B cell chronic lymphocytic leukemia patients.

Chronic lymphocytic leukemia (CLL) is the most common leukemia in adults in Western countries. It is characterized by heterogeneous clinical course of the disease and new prognostic factors are still needed. CD74 plays an important role in signal transduction in B cell proliferation and survival pathway. CD74 expression has been shown in solid tumors and has been connected with poor prognosis and tumor progression. The aim of the study was to evaluate the expression of CD74 in chronic lymphocytic leukemia patients with combination with other known prognostic factors. Expression of CD74 was determined in 90 patients and 28 healthy controls. CD74 expression was significantly higher in CLL group than in controls. There was positive correlation between CD74 and ZAP70 expression (p = 0.008). High expression of CD74 was positively correlated with more advanced stage of the disease (p = 0.02). No correlation was shown between CD74 and sex, mutational status IgVH and time to first treatment.

Polymorphisms of TNF and IL-10 genes and clinical outcome of patients with chronic lymphocytic leukemia.

Genetic variations in tumor necrosis factor (TNF) and interleukin-10 (IL-10) were reported to influence susceptibility to and outcome of patients with non-Hodgkin lymphoma. Therefore, we investigated whether single nucleotide polymorphisms in TNF and IL-10 may play a role in the clinical course of patients with chronic lymphocytic leukemia (CLL). TNF-308G>A, IL-10-3575T>A, and IL-10-1082A>G seem to be functionally relevant, were genotyped in 292 previously untreated patients with CLL. The control group consisted of 192 randomly selected blood donors. The patients carrying TNF-308GG and IL-10-1082AA genotypes presented a higher 3-year treatment-free survival (56.6 vs. 40.6%, P = 0.05) as well as a 10-year overall survival (OS) rates (92.3 vs. 57.6%, P = 0.005) than those with other TNF-308 and IL-10-1082 genotype combinations. Multivariate analysis demonstrated the Rai stage (P = 0.0002), IGHV mutation status (P = 0.01), TNF-308G>A (P = 0.03), and TNF/IL-10 polymorphism-based risk groups (P = 0.05) to be independent factors predicting OS. When the mutated IGHV patients were analyzed, the homozygotes TNF-308GG and IL-10-1082AA presented a higher 10-year OS rate than those carrying other TNF-308 and IL-10-1082 genotypes (100 vs. 67.7%, P = 0.01). In the unmutated IGHV patients, only the TNF-308G>A polymorphism influenced OS. The genetic variations in TNF and IL-10 genes work as independent predictors of survival and may play a role in the clinical course of CLL. It suggests inherited ability of the host to shift the balance between the Th1 and Th2 response, which in turn might contribute to the pathogenesis and prognosis of B-cell malignancies.

High expression of hematopoietic cell specific Lyn substrate-1 (HS1) predicts poor survival of B-cell chronic lymphocytic leukemia patients.

UNLABELLED: B-cell chronic lymphocytic leukemia (B-CLL) is the most common leukemia in adults in western countries. HS1 protein regulates leukemic cell migration and homing, and can indirectly promote disease progression and influence patient survival. The aim of this study was to evaluate HS1 expression in CLL patients in connection with other known prognostic factors and patients' survival. METHODS: 90 untreated CLL patients were included into the study. The control group consisted of 28 healthy matched people. HS1 detection was performed by western-blotting. Mutational status of IgVH, as well as CD38 and ZAP70 expression was also analyzed. RESULTS: HS1 expression was significantly higher in CLL patients comparing to controls. Positive correlation was shown between HS1 and: age (p=0.0454), Rai stage (p=0.0412), leukocytosis (p=0.0129) and beta-2-microglobulin (p=0.0342). Patients with lymphocyte doubling time shorter or equal to 6 months had higher expression of HS1. Patients with higher HS1 expression had shorter survival than those with lower HS1 expression (p=0.0329). CONCLUSIONS: We showed, that high HS1 expression predicts poor survival of chronic lymphocytic leukemia patients.

Hematopoietic stem cell transplantation for T315I-mutated chronic myelogenous leukemia.

BACKGROUND: The T315I mutation of BCR/ABL gene is known to produce complete resistance of chronic myelogenous leukemia (CML) to all currently available BCR/ABL inhibitors. The data suggesting poor median survival of these patients may indicate that they should be primary candidates for allogeneic stem cell transplantation (alloSCT). However, evidence on efficiency of this treatment modality in CML with T315I mutation is lacking. CASE REPORT: A 25-year-old patient was diagnosed with Philadelphia chromosome positive CML in accelerated phase. As he did not have an HLA-identical sibling or fully-matched unrelated bone marrow donor, treatment with low dose tyrosine kinase inhibitor - imatinib was initiated. Despite satisfactory hematological remission, he failed to achieve complete cytogenetic remission within the first year of treatment. Moreover, despite escalation of imatinib dosage, the disease relapsed after further 3 months of treatment. Molecular studies revealed T315I mutation of BCR/ABL gene. He responded poorly to interferon alpha (IFN-alpha) and we decided to perform alloSCT from a partially mismatched (8/10 HLA allele match) unrelated donor. The course of transplantation was complicated by staphylococcal sepsis, grade I skin acute GvHD and limited chronic skin GVHD. However, the goal of alloSCT was achieved and the patient remains in complete molecular remission at week +68 post-transplantation. CONCLUSIONS: The clinical course of this case supports the idea that allogeneic hematopoietic transplantation is a viable treatment option for patients with CML bearing T315I mutation.

Frequency of BCR-ABL gene mutations in Polish patients with chronic myeloid leukemia treated with imatinib: a final report of the MAPTEST study.

INTRODUCTION: The presence of BCR-ABL oncogene mutations in patients with chronic myeloid leukemia (CML) may be responsible for the failure of tyrosine kinase inhibitor treatment. OBJECTIVES: The aim of the study was to evaluate the frequency of BCR-ABL gene mutations in patients with CML (the MAPTEST study) treated with imatinib (IM). PATIENTS AND METHODS: Direct sequencing analysis of BCR-ABL gene was performed in 92 patients treated with IM for more than 3 months. The mean time of IM treatment was 18 months. At the time of the analysis, 75 patients were in the first chronic phase (CP), 4 in the second CP, 5 in the acceleration and 8 in the blastic phase. Fifty-seven patients (62%) were treated with IM at a daily dose of 400 mg and 35 patients with higher doses (600 or 800 mg daily). Inclusion criteria were based on the European Leukemia Net definitions for failure and suboptimal response to IM. RESULTS: Twelve mutations were detected in 11 of 92 patients, including 4 mutations (36.7%) diagnosed during CP, 3 (27.3%) in acceleration, and 4 (36.7%) in blast crisis. In 1 patient with lymphoid blast crisis of CML coexisting F359V and Y253F mutations were detected. In the whole group mutations were detected in 2 of 5 patients (40%) with primary resistance (M351T, F359V + Y253F) and in 9 of 87 patients (10.3%) (E255K, T315I-3x, M351T, E355G, F359V-2x) with acquired resistance to IM. CONCLUSIONS: The study confirmed the usefulness of BCR-ABL gene mutation screening in patients with CML resistant to IM therapy.

A diagnostically difficult case of chronic myeloid neoplasm with eosinophilia and abnormalities of PDGFRA effectively treated with imatinib in accelerated phase: case report.

Chronic myeloid neoplasm with eosinophilia and abnormalities of platelet-derived growth factor receptor alpha (PDGFRA), referred to until 2008 as chronic eosinophilic leukemia, is distinguished from hypereosinophilic syndrome (HES), if accompanied by genetic abnormalities that enable to determine eosinophil clonality. Typically, HES has a benign course and glucocorticosteroids suffice to achieve remission. In chronic myeloid neoplasm with eosinophilia and abnormalities of PDGFRA the FIP1L1-PDGFRA fusion gene can be detected. Its product is a protein showing tyrosine kinase activity leading to malignant proliferation of eosinophil precursors. Differential diagnosis of HES is often difficult because hypereosinophilia may also be reactive and may occur in many nonhematological as well as hematological disorders. Thus, reverse-transcription polymerase chain reaction (RT-PCR)is indicated in all patients with HES in order to detect the FIP1L1-PDGFRA transcript. Traditional treatment of chronic myeloid neoplasm with cytostatic drugs results in a short-term and transient remission or stabilization of the disease. We present the case of a 52-year-old patient with chronic myeloid neoplasm with eosinophilia and abnormalities of PDGFRA, in whom acceleration occurred after a year of cytostatic therapy with hydroxyurea and was successfully treated with imatinib. It was impossible to unequivocally determine the type of bone marrow disease based on histologic criteria, and a wide spectrum of molecular tests differentiating the type of myeloid proliferation were necessary to establish the diagnosis. RT-PCR did not reveal BCR-ABL or JAK2 V617F mutation. Further molecular testing showed rearrangement involving the FIP1L1 gene, thus enabling implementation of targeted therapy.

T-cell abnormalities are present at high frequencies in patients with hypereosinophilic syndrome.

BACKGROUND: A T-cell clone, thought to be the source of eosinophilopoietic cytokines, identified by clonal rearrangement of the T-cell receptor and by the presence of aberrant T-cell immunophenotype in peripheral blood defines lymphocytic variant of hypereosinophilic syndrome (L-HES). DESIGN AND METHODS: Peripheral blood samples from 42 patients who satisfied the diagnostic criteria for HES were studied for T-cell receptor clonal rearrangement by polymerase chain reaction according to BIOMED-2. The T-cell immunophenotype population was assessed in peripheral blood by flow cytometry. The FIP1L1-PDGFRA fusion gene was detected by nested polymerase chain reaction. RESULTS: Forty-two HES patients (18 males and 24 females) with a median age at diagnosis of 56 years (range 17-84) were examined in this study. Their median white blood cell count was 12.9 x 10(9)/L (range 5.3-121), with an absolute eosinophil count of 4.5 x 10(9)/L (range 1.5-99) and a median eosinophilic bone marrow infiltration of 30% (range 11-64). Among the 42 patients, clonal T-cell receptor rearrangements were detected in 18 patients (42.8%). Patients with T-cell receptor clonality included: T-cell receptor beta in 15 patients (35%), T-cell receptor gamma in 9 (21%) and T-cell receptor delta in 9 (21%) patients, respectively. Clonality was detected in all three T-cell receptor loci in 4 cases, in two loci in 7 patients and in one T-cell receptor locus in the remaining 7 patients. The FIP1L1-PDGFRA fusion transcript was absent in all but 2 patients with T-cell receptor clonality. Three patients out of 42 revealed an aberrant T-cell immunophenotype. In some patients, an abnormal CD4:CD8 ratio was demonstrated. CONCLUSIONS: T-cell abnormalities are present at high frequencies in patients with HES.

Characteristics of T-cell large granular lymphocyte proliferations associated with neutropenia and inflammatory arthropathy.

INTRODUCTION: The purpose of this study was to analyze the data of patients with T-cell large granular lymphocyte (T-LGL) lymphocytosis associated with inflammatory arthropathy or with no arthritis symptoms. METHODS: Clinical, serological as well as histopathological, immunohistochemical, and flow cytometric evaluations of blood/bone marrow of 21 patients with T-LGL lymphocytosis were performed. The bone marrow samples were also investigated for T-cell receptor (TCR) and immunoglobulin (IG) gene rearrangements by polymerase chain reaction with heteroduplex analysis. RESULTS: Neutropenia was observed in 21 patients, splenomegaly in 10, autoimmune diseases such as rheumatoid arthritis (RA) in 9, unclassified arthritis resembling RA in 2, and autoimmune thyroiditis in 5 patients. T-LGL leukemia was recognized in 19 cases. Features of Felty syndrome were observed in all RA patients, representing a spectrum of T-LGL proliferations from reactive polyclonal through transitional between reactive and monoclonal to T-LGL leukemia. Bone marrow trephines from T-LGL leukemia patients showed interstitial clusters and intrasinusoidal linear infiltrations of CD3+/CD8+/CD57+/granzyme B+ lymphocytes, reactive lymphoid nodules, and decreased or normal granulocyte precursor count with left-shifted maturation. In three-color flow cytometry (FCM), T-LGL leukemia cells demonstrated CD2, CD3, and CD8 expression as well as a combination of CD16, CD56, or CD57. Abnormalities of other T-cell antigen expressions (especially CD5, CD7, and CD43) were also detected. In patients with polyclonal T-LGL lymphocytosis, T cells were dispersed in the bone marrow and the expression of pan-T-cell antigens in FCM was normal. Molecular studies revealed TCRB and TCRG gene rearrangements in 13 patients and TCRB, TCRG, and TCRD in 4 patients. The most frequently rearranged regions of variable genes were Vbeta-Jbeta1, Jbeta2 and Vgamma If Vgamma10-Jgamma. Moreover, in 4 patients, additional rearrangements of IG kappa and lambda variable genes of B cells were also observed. CONCLUSION: RA and neutropenia patients represented a continuous spectrum of T-LGL proliferations, although monoclonal expansions were most frequently observed. The histopathological pattern and immunophenotype of bone marrow infiltration as well as molecular characteristics were similar in T-LGL leukemia patients with and without arthritis.

A single weekly dose of imatinib is sufficient to induce and maintain remission of chronic eosinophilic leukaemia in FIP1L1-PDGFRA-expressing patients.

Hypereosinophilic syndrome (HES) is defined as chronic, unexplained hypereosinophilia with organ involvement. A subset of HES patients presents an interstitial deletion in chromosome 4q12, which leads to the expression of an imatinib-responsive fusion gene, FIP1L1-PDGFRA. These patients are diagnosed as chronic eosinophilic leukaemia (CEL). We treated seven CEL and HES patients, six of which expressed FIP1L1-PDGFRA, with imatinib using initial daily doses ranging from 100 to 400 mg. In a remission maintenance phase, the patients were treated with imatinib once weekly. All imatinib-treated patients achieved a complete haematological remission (CHR), and five of the six patients with FIP1L1-PDGFRA expression exhibited molecular remission. The decreased imatinib doses were as follows: 200 mg/week in three patients, 100 mg/week in two patients and 100 mg/d in the remaining two patients. For remission maintenance, imatinib doses were set at 100 mg/week in five patients and 200 mg/week in two patients. At a median follow-up of 30 months all patients remained in CHR and FIP1L1-PDGFRA expression was undetectable in five of the six FIP1L1-PDGFRA-expressing patients. These data suggest that a single weekly dose of imatinib is sufficient to maintain remission in FIP1L1-PDGFRA- positive CEL patients.

Complete cytogenetic and molecular response after imatinib treatment for chronic myeloid leukemia in a patient with atypical karyotype and BCR-ABL b2a3 transcript.

The molecular hallmark of CML is the BCR-ABL fusion gene, usually with specific breakpoints within ABL intron 1 and BCR introns b2, b3, and e19. The amplification of the BCR-ABL hybrid gene resulting from additional copies of the Ph chromosome has been identified as a mechanism for imatinib (IM) resistance. Cytogenetic clonal evolution correlates with the accelerated phase of leukemia, whereas deletions in the derivative chromosome 9 are associated with a poor prognosis. Relevance in IM therapy is unclear. We report a case of a 39-year-old male with chronic phase CML. Cytogenetic studies showed a complex karyotype with additional copies of the Ph chromosome, sextasomy 8, and ASS gene deletion. An unusual aberrant fusion gene product was derived from the joining of BCR exon 13 (b2) and ABL exon 3 (a3). During IM treatment, the patient was monitored in 3- to 6-month intervals. Major cytogenetic response was achieved after 5 months; complete cytogenetic and molecular remission was reached after 8 months; after 22 months, normal karyotype and absence of the BCR-ABL product continued. Our data seem to confirm the data of others in regards to the b2a3 breakpoint, suggesting a better prognosis, regardless of other unfavorable factors.

Predictive value of RT-PCR PML-RARA transcript monitoring for extramedullary relapse of acute promyelocytic leukemia in the pleura, heart and pericardium after allogeneic SCT.

BACKGROUND: We report a patient with acute promyelocytic leukemia (APL) relapse in extremely rare sites--the pleura, heart and pericardium without evidence of bone marrow infiltration and with molecular evidence of disease after allogeneic stem cell transplantation (alloSCT). CASE DESCRIPTION: Presented patient underwent alloSCT in second complete hematological and cytogenetic remission with presence of promyelocytic leukemia-retinoic acid receptor A (PML-RARA) detected in reverse transcription-polymerase chain reaction (RT-PCR) with sensitivity of 10(-2). After transplant, this patient remained in complete hematological and cytogenetic remission but nested RT-PCR assays with detection thresholds of 10(-3)/10(-4) were positive for PML-RARA rearranged gene even chimerism tests showed 100% of donor profile. He was in a very good clinical condition and presented symptoms of transient limited chronic graft vs. host disease. Twenty one months after transplant, the leukemic relapse in the pleura, heart and pericardium was diagnosed. At that time, PML-RARA transcript detected in RT-PCR assay (10(-2)) was positive for the first time after transplant. During salvage chemotherapy he died because of cardiogenic shock. CONCLUSIONS: We conclude that detection of PML-RARA after alloSCT should be indication insightful diagnosis of medullary or extramedullary (EM) relapse. The imaging techniques of all possible sites of APL EM relapse have to be included.

Transformation in lymphomas--morphological, immunophenotypic and molecular features.

During the course of lymphoma, a clinically more aggressive process with different morphology may develop, referred to as lymphoma transformation. Clonal relationship and pathogenic mechanism of this process are widely debated. The aim of the study was to evaluate morphology, immunophenotype (including EBV status) and clonal relationship in nine cases of lymphoma transformation. Among the six patients with low grade B-cell lymphomas three transformed into high grade B-cell lymphomas (two into diffuse large B-cell lymphoma, one into Burkitt lymphoma) and three into Hodgkin lymphoma. Three other patients with Hodgkin lymphoma presented with transformation into diffuse large B-cell lymphoma in two patients and peripheral T-cell lymphoma in one patient. In all cases there was a sudden clinical change as well as change in morphology and phenotype. In five of the nine patients studied EBV-LMP1 was demonstrated by immunohistochemistry in large transformed lymphoma cells. In two cases molecular studies revealed a different pattern of immunoglobulin gene rearrangement in the large transformed cells as compared to the small cells of primary indolent lymphoma. Thus, they represented secondary, arising de novo neoplasm.

Expression and oncogenic role of Brk (PTK6/Sik) protein tyrosine kinase in lymphocytes.

Tyrosine kinases play a fundamental role in cell proliferation, survival, adhesion, and motility and have also been shown to mediate malignant cell transformation. Here we describe constitutive expression of the protein tyrosine kinase Brk in a large proportion of cutaneous T-cell lymphomas and other transformed T- and B-cell populations. The kinase is expressed in the nuclear localization and activated state. Brk expression was also induced in normal T cells on their activation. Introduced expression of the Brk gene resulted in markedly diminished cytokine and growth factor dependence of transfected BaF3 lymphocytes in regard to their in vitro proliferation and survival. Brk also conferred in vivo oncogenicity on the BaF3 cells. siRNA-mediated inhibition of the endogenous Brk in malignant T cells diminished their growth and survival capacity. These findings document inducible expression of Brk in normal T lymphocytes and persistent expression of the activated kinase in malignant T and B cells. Furthermore, our results indicate that Brk may play a key role in lymphomagenesis, hence identifying the kinase as a potential therapeutic target in lymphomas.

Immunosuppressive TOR kinase inhibitor everolimus (RAD) suppresses growth of cells derived from posttransplant lymphoproliferative disorder at allograft-protecting doses.

BACKGROUND: Posttransplant lymphoproliferative disorders (PTLDs) represent a life-threatening complication of standard immunosuppressive therapy. The impact of novel, rapamycin-related immunosuppressive drugs on the pathogenesis of PTLDs remains undefined. METHODS: We tested the effect of everolimus (RAD, Novartis Pharma AG, Basel, Switzerland) on human PTLD-derived cells using in vitro assays and an in vivo severe combined immunodeficiency disease mouse xenotransplant model. RESULTS: Everolimus profoundly inhibited the proliferation, cell-cycle progression, and survival of the PTLD-1 cell line established from a pulmonary PTLD. Equally profound inhibition of PTLD-1 growth was achieved in vivo at well-tolerated everolimus doses of 0.5 to 5 mg/kg per day. Five mg/kg per day of everolimus, given once per day, inhibited PTLD-1 tumor volume gain by more than 10-fold in treated mice compared with untreated mice. Because the subsequent pharmacokinetic analysis indicated rapid everolimus absorption, distribution, and clearance in mice (with a half-life of 3 to 6 hr and maximum drug blood concentration reached after 0.5 to 1 hr), treatment was changed to a twice-daily regimen. Everolimus given twice daily at 0.5 mg/kg per dose inhibited tumor-volume gain by more than 60-fold and at 0.25 mg/kg per dose by more than 10-fold. Similar everolimus doses were required to prevent graft rejection in a mouse heart allotransplantation model; the highest dose tested (1.5 mg/kg twice daily) resulted in long-term graft survival in all mice that underwent transplantation. CONCLUSIONS: Everolimus displays a potent inhibitory effect on PTLD-derived cells in vitro and in vivo in a dose range leading to prevention of allograft rejection and may prove effective in both the prevention and treatment of PTLDs in transplant patients.

Expression of SHP-1 phosphatase indicates post-germinal center cell derivation of B-cell posttransplant lymphoproliferative disorders.

SHP-1 tyrosine phosphatase acts as a negative regulator of signaling by receptors for growth factors, cytokines, and chemokines and by receptors involved in immune response. Our recent study showed that SHP-1 is tightly regulated at various stages of B-cell differentiation and is expressed in the mantle and marginal zones, interfollicular B cells, and plasma cells, whereas it is nondetectable in germinal center cells. In this study we evaluated expression of SHP-1 in vitro and in vivo in nine cell lines representing three different types of EBV+ B-cell populations closely resembling or derived from posttransplant lymphoproliferative disorders (PTLDs). Furthermore, we examined tissue samples from 58 patients with B-cell PTLDs, both EBV+ (85% of the cases analyzed) and EBV- (15%). SHP-1 protein was strongly expressed in all cell lines and PTLD cases. In addition, the PTLD cases were essentially negative for germinal center B-cell markers: none expressed CD10 and only one expressed BCL-6. More than 40% expressed a late post-germinal B-cell marker, CD138. The universal expression of SHP-1, lack of expression of CD10 and BCL-6, and frequent expression of CD138 suggest that PTLDs are derived from post-germinal center B cells regardless of the EBV cell infection status. Based on the immunophenotype, B-cell PTLDs could be divided into two broad categories corresponding to the early (CD10-/BCL-6-/SHP-1+/CD138-) and late (CD10-/BCL-6-/SHP-1+/CD138+) post-germinal center cells. By being expressed earlier, SHP-1 is a more sensitive marker of post-germinal center B cells than CD138, which is seen on the terminally differentiated immunoblasts and plasma cells.