Increase in Frequency of Myeloid-Derived Suppressor Cells in the Bone Marrow of Myeloproliferative Neoplasm: Potential Implications in Myelofibrosis.

The Philadelphia-negative myeloproliferative neoplasms (MPNs), defined as clonal disorders of the hematopoietic stem cells, are characterized by the proliferation of mature myeloid cells in the bone marrow and a chronic inflammatory status impacting the initiation, progression, and symptomatology of the malignancies. There are three main entities defined as essential thrombocythemia (ET), polycythemia vera (PV), and primary myelofibrosis (PMF), and genetically classified by JAK2V617F, CALR, or MPL mutations. In MPNs, due to the overproduction of inflammatory cytokines by the neoplastic cells and non-transformed immune cells, chronic inflammation may provoke the generation and expansion of myeloid-derived suppressors cells (MDSCs) that highly influence the adaptive immune response. Although peripheral blood MDSC levels are elevated, their frequency in the bone marrow of MPNs patients is not well elucidated yet. Our results indicated increased levels of total (T)-MDSCs (CD33+HLA-DR-/low) and polymorphonuclear (PMN)-MDSCs (CD33+/HLA-DRlow/CD15+/CD14-) in the bone marrow and peripheral blood of all three types of MPNs malignancies. However, these bone marrow MDSCs-increased frequencies did not correlate with the clinical parameters, such as hepatomegaly, leukocytes, hemoglobin, or platelet levels, or with JAK2 and CALR mutations. Besides, bone marrow MDSCs, from ET, PV, and PMF patients, exhibited immunosuppressive function, determined as T-cell proliferation inhibition. Notably, the highest T-MDSCs and PMN-MDSC levels were found in PMF samples, and the increased MDSCs frequency strongly correlated with the degree of myelofibrosis. Thus, these data together indicate that the immunosuppressive MDSCs population is increased in the bone marrow of MPNs patients and may be implicated in generating a fibrotic microenvironment.

Hydroxyurea Induces Bone Marrow Mesenchymal Stromal Cells Senescence and Modifies Cell Functionality In Vitro.

Hydroxyurea (HU) is an antineoplastic agent that functions as an antimetabolite compound by inhibiting the ribonucleotide reductase. HU acts mainly as a cytostatic drug that through DNA replication stress may trigger a premature senescence-like cell phenotype, though its influence on bone marrow-derived mesenchymal stem/stromal cell (BMMSC) functions has not elucidated yet. Our results indicate that HU inhibits the growth of human BMMSC alongside senescence-like changes in both morphology and replicative potential, provokes cell cycle arrest at the S phase without affecting cellular viability and induces the expression of senescence-associated ß-galactosidase and p16INK4. Moreover, HU-induced senescent BMMSC, although they did not change MSC markers expression, exhibited reduced capacity osteogenic and adipogenic differentiation. Conversely, HU treatment increased immunoregulatory functions of BMMSC compared with untreated cells and determined by T-cell proliferation. Interestingly, HU did not influence the capacity of BMMSC to induce monocytic myeloid-derived suppressor cells. Thus, these results suggest that HU improves the BMMSC functions on the T-cell inhibition and preserves their interaction with myeloid cell compartment. Mechanistically, BMMSC under HU treatment displayed a downregulation of mTOR and p38 MAPK signaling that may explain the reduced cell differentiation and increased immunomodulation activities. Together, the results obtained in this investigation suggest that HU by inducing senescence-like phenotype of BMMSC influences their cellular differentiation and immunoregulatory functions.

Hydroxyurea-induced senescent peripheral blood mesenchymal stromal cells inhibit bystander cell proliferation of JAK2V617F-positive human erythroleukemia cells.

Hydroxyurea (HU) is a nonalkylating antineoplastic agent used in the treatment of hematological malignancies. HU is a DNA replication stress inducer, and as such, it may induce a premature senescence-like cell phenotype; however, its repercussion on bystander cell proliferation has not been revealed so far. Our results indicate that HU strongly inhibited peripheral blood mesenchymal stromal cells (PBMSC) proliferation by cell cycle arrest in S phase, and that, consequently, PBMSC acquire senescence-related phenotypical changes. HU-treated PBMSC display increased senescence-associated ß-galactosidase levels and p16INK4 expression, as well as DNA damage response and genotoxic effects, evidenced by expression of γH2A.X and micronuclei. Moreover, HU-induced PBMSC senescence is mediated by increased reactive oxygen species (ROS) levels, as demonstrated by the inhibition of senescence markers in the presence of ROS scavenger N-acetylcysteine and NADPH oxidase inhibitor Apocynin. To determine the HU-induced bystander effect, we used the JAK2V617F-positive human erythroleukemia 92.1.7 (HEL) cells. Co-culture with HU-induced senescent PBMSC (HU-S-PBMSC) strongly inhibited bystander HEL cell proliferation, and this effect is mediated by both ROS and transforming growth factor (TGF)-ß expression. Besides induction of premature senescence, HU educates PBMSC toward an inhibitory phenotype of HEL cell proliferation. Finally, our study contributes to the understanding of the role of HU-induced PBMSC senescence as a potential adjuvant in hematological malignancy therapies.

Measuring Patients' Knowledge About Adverse Effects of Angiotensin-Converting Enzyme Inhibitors.

BACKGROUND: Knowledge about adverse effects of medications is an important part of proper medication use and prerequisite for good treatment adherence. OBJECTIVE: The aim of our study was to construct, develop, and test a new questionnaire for the measurement of patients' knowledge about adverse drug reactions of angiotensin-converting enzyme (ACE) inhibitors. METHODS: The 8-item questionnaire was constructed to measure adverse reactions to ACE inhibitors. The questions were closed, with 7 offered answers, in the form of a Likert scale. It was tested for psychometric properties on patients who visited their general practitioners at state-owned health facilities in 5 Serbian cities: Belgrade, Kragujevac, Banja Luka, Gracanica, and Despotovac. RESULTS: The questionnaire was tested on 259 patients from general practice, taking an ACE inhibitor for more than 3 months. Experience with at least 1 adverse effect of ACE inhibitor was reported in 64 patients (24.7%), only 94 patients (36.3%) previously received any form of information about at least 1 adverse effect of ACE inhibitors from health workers, and only 42% expressed knowledge of any adverse events. The patients who were informed knew about the following adverse events as phrased in the official patient information leaflets: severe dizziness or light-headedness (44%); cough (37%); swelling of the hands, face, lips, or tongue (32%); indigestion (22%); headache (51%); and difficulty in breathing (15%). The questionnaire showed satisfactory internal consistency, with Cronbach α of 0.767, and individual scores correlated with general education of the patients. Factorial analysis revealed 2 domains (subscales): the first one with 5 questions is directed to adverse effects the patients may physically experience directly, whereas the second with 3 questions measures knowledge about adverse effects that could be experienced only indirectly, through conditions caused by the adverse effects. CONCLUSIONS: The questionnaire about knowledge of ACE inhibitors' adverse effects is a reliable and probably valid instrument for measuring patients' knowledge about adverse effects of ACE inhibitors.

Prognostic Significance of Cereblon Expression in Patients With Multiple Myeloma.

BACKGROUND: To personalize the treatment approach for patients with multiple myeloma (MM), molecular markers such as cereblon (CRBN) are currently the focus of investigation. The aim of the present study was to test the prognostic significance of CRBN expression in MM patients ineligible for autologous stem cell transplantation (ASCT). PATIENTS AND METHODS: The data from 92 previously untreated patients were analyzed. The distribution according to the International Staging System score was 26.1%, 30.4%, and 43.5% with a score of 1, 2, and 3, respectively. Thalidomide- and bortezomib-based combinations were used in 83.7% and 16.3% of the patients, respectively. RESULTS: A treatment response (complete remission, very good partial remission, partial remission) was achieved in 83.7% of the patients and correlated with high CRBN expression (P = .006), mainly in the patients treated with thalidomide (P = .028). Low CRBN expression affected progression-free survival (PFS; P = .017) but not overall survival (OS) in patients treated with thalidomide and had no influence on OS in the bortezomib group. In the Cox regression model, low CRBN expression was the most important prognostic parameter that influenced PFS in the thalidomide-treated patients (P = .012). CONCLUSION: CRBN expression is of prognostic value in MM patients ineligible for ASCT treated with thalidomide as an immunomodulatory drug. With low expression indicating a possible suboptimal treatment outcome, measurement of CRBN expression might serve as additional prognostic tool in the personalized treatment approach.

The NO-modified HIV protease inhibitor as a valuable drug for hematological malignancies: Role of p70S6K.

Covalent attachment of NO to the first approved HIV protease inhibitor Saquinavir (Saq-NO) expands the therapeutic potential of the original drug. Apart from retained antiviral activity, the modified drug exerts strong antitumor effects and lower toxicity. In the present study, we have evaluated the sensitivity of different hematological malignancies to Saq-NO. Saq-NO efficiently diminished the viability of Jurkat, Raji, HL-60 and K562 cells. While Jurkat and Raji cells (established from pediatric patients) displayed abrogated proliferative potential, HL-60 and K652 cells (originated from adults) exposed to Saq-NO treatment underwent caspase dependent apoptosis. In addition, similar sensitivity to Saq-NO was observed in mononuclear blood cells obtained from pediatric patients with acute lymphoblastic leukemia (ALL) and adult patients with acute myeloid leukemia (AML). Western blot analysis indicated p70S6 kinase as a possible intracellular target of Saq-NO action. Moreover, the addition of a NO moiety to Lopinavir resulted in improved antitumor potential as compared to the parental compound, suggesting that NO-derived HIV protease inhibitors are a potential new source of anticancer drugs with unique mode of action.

JAK2V617F Mutation in a Patient with B-cell Chronic Lymphocytic Leukemia and Prefibrotic Primary Myelofibrosis.

INTRODUCTION: Secondary malignancies, particularly solid tumors, are common in patients with chronic lymphocytic leukemia (CLL), but association of myeloproliferative neoplasms and chronic lymphocytic leukemia in the same patient is very rare. CASE OUTLINE: We report of a 67-year-old man with B-cell chronic lymphoid leukemia (B-CLL) who developed primary myelofibrosis (PMF) nine years after initial diagnosis. Patient received alkylation agents and purine analogue, which can be a predisposing factor for the development of myeloproliferative neoplasms. JAK2V617F mutation was not present initially at the time of CLL diagnosis, but was found after nine years when PMF occurred, which indicates that B-CLL and PMF represent two separate clonal origin neoplasms. CONCLUSION: Pathogenic mechanisms for the development of myeloproliferative and lymphoproliferative neoplasms in the same patient are unknown. Further research is needed to determine whether these malignancies originate from two different cell clones or arise from the same pluripotent hematopoietic stem cell.

The emergence of non-secretory multiple myeloma during the non-cytotoxic treatment of essential thrombocythemia: a case report.

INTRODUCTION: The emergence of multiple myeloma as a second malignancy in patients with essential thrombocythemia is extremely rare. Several cases have been published so far, pointing out the impact of a cytotoxic effect during treatment of essential thrombocythemia on the development of multiple myeloma. CASE PRESENTATION: We report the case of a 52-year-old Caucasian man who presented to our hospital because of leukocytosis, a slightly decreased hemoglobin level and thrombocytosis. After a complete hematological work-up, essential thrombocythemia was diagnosed. The patient was included in a multicenter clinical study, treated with anagrelide and his platelet counts were maintained in the normal range for more than 3 years. A sudden drop in his hemoglobin level with normal leukocyte and platelet count occurred at the same time as a back pain. Magnetic resonance imaging of his spine revealed the existence of a pathological fracture of Th4, the collapse of the upper edge of Th7 and osteolytic lesions of multiple thoracic vertebrae. Repeated hematological examinations, including bone biopsy with immunohistochemistry, disclosed diagnosis of multiple myeloma of the non-secretory type. CONCLUSIONS: To the best of our knowledge this is the first published case in which multiple myeloma developed during the treatment of essential thrombocythemia with the non-cytotoxic drug anagrelide. Our attempts to find a common origin for the coexistence of multiple myeloma and essential thrombocythemia have not confirmed the genetic basis of their appearance. Further studies are needed to determine the biological impact of this coexistence.

Prognostic significance of epigenetic inactivation of p16, p15, MGMT and DAPK genes in follicular lymphoma.

In this study, methylation-specific polymerase chain reaction was used to investigate the role and potential prognostic significance of the methylation status of p16, p15, MGMT and DAPK genes in 32 specimens of follicular lymphoma (FL). Hypermethylation of p15 gene was associated with lower hemoglobin level (P = 0.020) and MGMT/DAPK comethylation with relapsed disease (P = 0.018). Among all patients with FL, there was no significant difference in the overall survival between those with hypermethylated and unmethylated of any examined genes. Therefore, we analyzed methylation in the different groups according to FL International Prognostic Index (FLIPI) and tumor grade. In the high-risk group, patients with hypermethylated p16 gene had significant lower overall survival than those with unmethylated p16 (P = 0.006) and trend toward shorter failure-free survival (P = 0.068). In the same risk group, there was a trend toward longer overall survival for patients with hypermethylated MGMT gene, compared to those with unmethylated MGMT gene (P = 0.066). p15 methylation had impact on shorter overall survival in grade I group of patients (P = 0.013), and DAPK methylation tended to have impact on shorter failure-free survival in the whole examined group (P = 0.079). Our results suggest that promoter methylation of p16 and MGMT genes could have prognostic value when used in combination with the FLIPI and p15 methylation in combination with tumor grade. Concurrent methylation of MGMT and DAPK genes could be the marker of tumor chemoresistance and disease recurrence.

Induction chemotherapy versus palliative treatment for acute myeloid leukemia in a consecutive cohort of elderly patients.

A retrospective survey of 210 consecutive patients aged ≥ 65 years (median age 69 years, range 65-88 years) with acute myeloid leukemia (AML) diagnosed at a single center over a 6-year period (January 2001 to December 2006) is presented. De novo AML was diagnosed in 179 (85.2 %) patients and 31 (14.7 %) patients had a secondary AML. Twenty-three patients had M0 (11 %), 36 M1 (17.15 %), 57 M2 (27.1 %), eight M3 (3.8 %), 45 M4 (21.4 %), 31 M5 (14.8 %), one M6 (0.5 %), one M7 (0.5 %), and eight patients had unclassified myeloid leukemia (3.8 %) according to French-American-British (FAB) Study Group Classification. Eight patients with M3 (acute promyelocytic leukemia) were excluded from the study. Cytogenetic analysis was performed in 172/202 (85 %) patients. The normal karyotype was found in 81/172 (47 %), high risk aberrations in 32/172 (18.6 %), and favorable karyotype in 13/172 (7.5 %) patients. Supportive and palliative therapies were applied in 115 (56.9 %) patients, a no induction chemotherapy (NIC) group, and 87 (43.1 %) patients received induction chemotherapy (IC group). Complete remission (CR) was achieved in 45/87 (51.7 %) in the IC group and in 5/115 (4.3 %) in the NIC group of patients. After a median follow up of 4 years, 194 (96 %) patients died. The variables significantly associated with a longer overall survival (OS) by univariate analysis were an age of <75 years, a better ECOG performance status (PS) (p = 0.000, CI 95.0 %, 1.358-2.049), a serum LDH activity <600 U/l (p = 0.000, CI 95.0 %, 1.465-2.946), lower white blood cell (WBC) count at diagnosis (p = 0.011, CI 95.0 %, 1.102-2.100), lower comorbidity HCT-CI index (p = 0.000, CI 95 % 2.209-3.458), absence of splenomegaly (p = 0.015, CI 95.0 %, 1.082-2.102) and hepatomegaly (p = 0.008, CI 95.0 %, 1.125-2.171), and no preceding nonhematological malignancy. Multivariate analysis showed that significant factors affecting OS in the IC group were achievement of CR (p = 0.000), the ECOG PS (p = 0.045) and the ECOG PS (p = 0.000), and HCT-CI (p = 0.000) in the NIC group of elderly patients. The present study suggests that a subgroup of elderly patients with both ECOG PS and HCT-CI ≤ 2 at presentation may be eligible for intensive induction chemotherapy.

Reversal of FLT3 mutational status and sustained expression of NPM1 mutation in paired presentation, and relapse samples in a patient with acute myeloid leukemia.

We report a case of de novo acute myeloid leukemia (AML) with unstable FLT3 gene mutations and stable NPM1 mutation. FLT3/D835 and NPM1 (Type A) mutations were detected upon diagnosis. During the relapse, the FLT3/D835 mutation changed to an FLT3/ITD mutation while the NPM1 (Type A) mutation was retained. Cytogenetic analyses showed the normal karyotype at diagnosis and relapse. Our findings raise interesting questions about the significance of these mutations in the leukemogenic process, about their stability during the evolution of the disease, and regarding the selection of appropriate molecular markers for the monitoring of minimal residual disease.

Response to cladribine in patient with systemic mastocytosis.

INTRODUCTION: Systemic mastocytosis is a heterogeneous group of hematological disorders characterized by accumulation of mast cells in different organs. CASE REPORT: A 41-year-old woman presented with a three-year history of fatigue, occasional diarrhea, mild fever, skin rash and splenomegaly. Laboratory results showed severe anemia and thrombocytopenia. Cytological and histological investigation of bone marrow showed a marked increase of mast cells infiltration with following immunophenotype: CD117+, CD68+, CD34-, MPO-, CD15-. She was treated with cladribine 0.15 mg/kg body weight from day 1 to day 5, a total of six cycles, and achieved a good partial response, transfusion independency and normalization of spleen size. Although the patient responded to the treatment, the relapse with splenomegaly and bicytopenia was observed after 10 months. CONCLUSION: Cladribine therapy was efficient in the patient' with systemic mastocytosis but the response was transient, so there is the need to search for new therapeutic options and more effective strategies in the treatment of patients with aggressive mast cell disorders.

[Progression of nodal marginal zone lymphoma into diffuse large B cell lymphoma in a patient with Sjögren's syndrome].

INTRODUCTION: Sjögren's syndrome is a chronic autoimmune disorder carrying the risk of the development of non-Hodgkin's lymphoma, most frequently marginal zone lymphoma. CASE OUTLINE: A 66-year-old male patient with Sjögren's syndrome, after a year of the disease, developed a nodal marginal zone lymphoma with lymphoma cells in peripheral blood which had the following immunophenotype: CD19, CD20, CD22, CD19/kappa, CD79b+. After six cycles of chemotherapy according to CHOP protocol (cyclophosphamide, doxorubicin, vincristine and prednisone) disease remission was achieved lasting four months, followed by enlargement of lymph nodes in all areas (generalized lymphadenopathy), splenomegaly and enlargement of the right parotid gland. Bone marrow biopsy and histology confirmed lymphoma of the same morphologic and immunohistochemic profile. Biopsy of a very enlarged hard right parotid gland, by using histology and immunohistochemistry, showed lymphoid tumour tissue with blast appearance and a number of nucleoli corresponding to centroblasts and less to immunoblasts. Immunophenotypes of these cells were as follows: CD79alfa+, CD20+, CD3-, bcl-2-; proliferative activity measured with KI-67 was high rating 60%. Histology and immunohistochemistry showed the co-existence of a diffuse large B cell lymphoma with marginal zone lymphoma. In spite of aggressive chemotherapy treatment according to protocol ESHAP (Vepesid 200 mg i.v. on 1st and 2nd day and 100 mg on 3rd, 4th and 5th day; Cisplatin 20-20-10 mg on 1st to 4th day) the disease showed a progressive course. CONCLUSION: In patients with Sjögren's syndrome, the possibility of lymphoma should be kept in mind and in suspected cases timely diagnostic and therapeutic measures should be undertaken.

[Diffuse large cell lymphoma and colon adenocarcinoma in patient with Waldenström's macroglobulinaemia].

INTRODUCTION: Waldenström's macroglobulinaemia is a rare B cell lymphoproliferative disorder characterized by lymphoplasmocyte bone marrow infiltration and monoclonal IgM gammopathy. In the majority of cases, Waldenström's macroglobulinaemia is a chronic disease with variable course. Therapy consists of alkylating agents, purine analogs and antiCD20 monoclonal antibody. In the literature, there have been descriptions of rare cases of progression of Waldenström's macroglobulinaemia to aggressive lymphoma, as well as secondary carcinoma in the patients after treatment of macroglobulinaemia. CASE OUTLINE: A 63-year-old patient was diagnosed with serum monoclonal IgM kappa gammopathy (Waldenström's macroglobulinaemia). Chemotherapy was applied and a good clinical and haematological response had been achieved. Ten years later, the patient was diagnosed with colon adenocarcinoma as a secondary malignancy, and operated on. Within one month, the patient rapidly developed a large neck tumour mass. Tumour biopsy revealed the diagnosis of diffuse large B-cell lymphoma with the expression of monoclonal lambda chain, which more likely pointed out to coexistence of two different B cell lymphoproliferative disorders, rather than the transformation of Waldenström's macroglobulinaemia to aggressive lymphoma. The patient was treated with chemotherapy following R-CHOP protocol, and clinical remission was achieved. Seven months later, despite the successful treatment of lymphoproliferative disorder, dissemination of adenocarcinoma led to the lethal outcome. CONCLUSION: The patient was diagnosed with a rare occurrence of three neoplastic diseases: Waldenstrom's macroglobulinaemia, colon adenocarcinoma and diffuse large B cell lymphoma. The possible mechanisms of the combined appearance of lymphoproliferative and other malignant diseases include the previous treatment with alkylating agents, genetic, immunomodulatory and environmental factors.

Novel ORC4L gene mutation in B-cell lymphoproliferative disorders.

B-cell lymphoproliferative disorders are characterized by marked genetic, morphological, and clinical heterogeneity. The identification of prognostic markers could help to develop risk-adapted treatment strategies. Because proliferation of cells is essential for tumor growth, analysis of the cell cycle might give additional information on tumor progression and clinical behavior. Because initiation of DNA replication represents a significant step in cell division, it is worthwhile to focus the attention to the origin recognition complex (ORC), protein complex essential for initiation of DNA replication. Studies have already shown that ORC-associated factors give a more accurate assessment of cell proliferation than previous markers for many types of malignancies, but so far there have been no studies of eventual role of ORC4L in B-cell lymphoproliferative disorders. Here, we describe 3 patients with B-cell lymphoproliferative disorders (2 with non-Hodgkin lymphoma and 1 with nonsecretory multiple myeloma) carrying a novel A286V mutation within ORC4L gene. All 3 patients were in the advanced stage of disease, but their response to the chemotherapy treatment was good and they achieved complete clinical remission in a relatively short period. Although the functional relevance of this mutation has not yet been elucidated, our observation raises a possibility that A286V mutation, which is constitutively present in these patients, might represent a favorable prognostic marker in B-cell lymphoproliferative disorders.