Molecular characterization of the idiopathic hypereosinophilic syndrome (HES) in 35 French patients with normal conventional cytogenetics.

Idiopathic hypereosinophilic syndrome (HES) characterized by unexplained and persistent hypereosinophilia is heterogeneous and comprises several entities: a myeloproliferative form where myeloid lineages are involved with the interstitial chromosome 4q12 deletion leading to fusion between FIP1L1 and PDGFRA genes, the latter acquiring increased tyrosine kinase activity. And a lymphocytic variant, where hypereosinophilia is secondary to a primitive T lymphoid disorder demonstrated by the presence of a circulating T-cell clone. We performed molecular characterization of HES in 35 patients with normal karyotype by conventional cytogenetic analysis. TCRgamma gene rearrangements suggesting T clonality were seen in 11 (31%) patients, and FIP1L1-PDGFRA by RT-PCR in six (17%) of 35 patients, who showed no evidence of T-cell clonality. An elevated serum tryptase level was observed in FIP1L1-PDGFRA-positive patients responding to imatinib, whereas serum IL-5 levels were not elevated in T-cell associated hypereosinophilia. Sequencing FIP1L1-PDGFRA revealed scattered breakpoints in FIP1L1-exons (10-13), whereas breakpoints were restricted to exon 12 of PDGFRA. In the 29 patients without FIP1L1-PDGFRA, no activating mutation of PDGFRA/PDGFRB was detected; however; one patient responded to imatinib. FISH analysis of the 4q12 deletion was concordant with FIP1L1-PDGFRA RT-PCR data. Further investigation of the nature of FIP1L1-PDGFRA affected cells will improve the classification of HES.     

Effect of vancomycin initial dosing on time to systemic inflammatory response syndrome resolution in patients with methicillin-resistant Staphylococcus aureus bacteremia

Current guidelines suggest using vancomycin-loading doses for complicated infections despite a lack of evidence to support this practice. To address this gap, we performed a single-centre cohort study of 124 patients with sepsis due to methicillin-resistant Staphylococcus aureus bacteremia. Patients were allocated into two groups based on initial dose of vancomycin, <20 mg/kg or ≥20 mg/kg, and evaluated for time to resolution of systemic inflammatory response syndrome (SIRS). Among a cohort of 124 patients, 87 received vancomycin initial doses <20 mg/kg and 37 received ≥20 mg/kg. The median time to SIRS resolution was 109 h in the <20 mg/kg group compared to 67 h in the ≥20 mg/kg group. Cox proportional hazard modelling showed a faster resolution of SIRS in the ≥20 mg/kg group (HR = 1.72[1.09–2.73]). Vancomycin initial doses of ≥20 mg/kg led to faster resolution of SIRS although further studies are needed to evaluate the safety and efficacy of this approach.     

Response of idiopathic hypereosinophilic syndrome to treatment with imatinib mesylate

Idiopathic hypereosinophilic syndrome (HES) is a rare hematologic disorder characterized by persistent eosinophilia with organ involvement. Patients with HES have a poor prognosis, but the disease course can be heterogeneous. Treatment of HES has included corticosteroids, chemotherapeutic agents such as cyclophosphamide, vincristine, hydroxyrea, and most recently interferon-alpha (IFN-alpha) which has shown long-term beneficial effects. We herein report on a patient with HES who had disease resistant to steroids, and chemotherapy with 2-chlorodeoxyadenosine and cytarabine, but who had a significant response after only 8 days of treatment with imatinib mesylate 100mg daily. The possible mechanism of response is discussed. This observation may lead to a better understanding of the pathophysiology of HES, and may provide a new form of effective therapy for the disease.     

Heterogeneity of O(6)-alkylguanine-DNA alkyltransferase activity in colorectal cancer: implications for treatment

OBJECTIVES: MGMT (O(6)-alkylguanine-DNA alkyltransferase) reverses the carcinogenic, mutagenic and cytotoxic effects of alkylating agents. Measurement of MGMT activity in tumours might thus be of use in selecting those patients with colorectal cancer who may be sensitive to adjuvant alkylating agent therapy. The aim of this study was to assess whether measurement of MGMT activity in a single tumour biopsy is representative of the whole tumour. METHODS: Multiple symmetrically spaced biopsies were taken from colorectal cancers obtained from 9 patients. MGMT activity was then measured in cell-free extracts by quantifying the transfer of [(3)H]methyl group from calf thymus DNA methylated in vitro with N-nitroso-N-[(3)H]-methylurea to the MGMT protein. RESULTS: MGMT activity was detected in all tumour samples with the activity ranging between 3.6 and 36.2 fmol/microg DNA and 202-1,986 fmol/mg protein. Heterogeneity in MGMT activity (ratio of maximum/minimum MGMT levels per tumour) varied between 1.3 and 5.4. CONCLUSIONS: Measurement of MGMT activity in a single biopsy is not necessarily indicative of the level throughout the tumour. The response of colorectal cancers to alkylating agent treatment is likely to be non-uniform both within the tumour and between patients.     

New diagnostic tool for differentiation of idiopathic hypereosinophilic syndrome (HES) and secondary eosinophilic states

The hypereosinophilic syndrome (HES) is a very rare disease, characterized by persistent eosinophilia with tissue involvement and organ dysfunction which often precedes a subsequent T cell lymphoma. Interleukin-5 secreted by a T lymphocyte subpopulation has been described in previous reports as the most important factor responsible for the prolonged lifespan of the eosinophils. The goal of the present study was to describe a fast, simple diagnostic method for the differentiation of HES and secondary eosinophilic states. Beside the surface marker analysis of peripheral blood mononuclear cells (PBMC) we measured surface bound IgE molecules on lymphocytes and eosinophil cells, intracellular cytokines (IL-5, INFgamma) in CD4+ lymphocytes and eosinophil major basic protein (MBP) in eosinophils using flow cytometric detection method. The appearance of an IL-5 producing cell population with a decreased number of INFgamma positive lymphocytes was characteristic for the blood samples of HES patients. Predominance of Th2 cells with the appearance of a CD8+/CD3 /CD56+ cell population was restricted for the HES cases and could not be detected in secondary eosinophilic individuals. Our flow cytometric cytokine detection method (with parallel cell surface marker analysis) does not require cell separation or long term cell culture steps previously described for the detection of IL-5 producing cells. Therefore it seems to be a more appropriate approach for the differential diagnosis of primary and secondary eosinophilic states.     

Imatinib has limited therapeutic activity for hypereosinophilic syndrome patients with unknown or negative PDGFRα mutation status

Hypereosinophilic syndrome (HES) is characterized by sustained non-clonal blood and tissue eosinophilia, leading to end-organ damage. With a molecular/cytogenetic clonality marker, the disease is classified as chronic eosinophilic leukemia (CEL). Efficacy of imatinib mesylate is well established in CEL with FIP1L1-platelet-derived growth factor-α (PDGFRα) rearrangement. We treated with imatinib 18 HES patients (11 PDGFRα-negative and 7 PDGFRα-status unknown). One patient with unknown PDGFRα status achieved complete hematologic response, and two (one PDGFRα negative and one status unknown) achieved partial hematologic response. Our results confirm low response rate to imatinib in HES patients with unknown or negative PDGFRα status, and underscore the need for new therapeutic options for this disorder.     

C-myc activation impairs the NF-kappaB and the interferon response: implications for the pathogenesis of Burkitt's lymphoma

Deregulation of the proto-oncogene c-myc is a key event in the pathogenesis of many tumors. A paradigm is the activation of the c-myc gene by chromosomal translocations in Burkitt lymphoma (BL). Despite expression of a restricted set of Epstein-Barr viral (EBV) antigens, BL cells are not recognized by antigen-specific cytotoxic T cells (CTLs) because of their inability to process and present HLA class I-restricted antigens. In contrast, cells of EBV-driven posttransplant lymphoproliferative disease (PTLD) are recognized and rejected by EBV-specific CTLs. It is not known whether the poor immunogenicity of BL cells is due to nonexpression of viral antigens, overexpression of c-myc, or both. To understand the basis for immune recognition and escape, we have compared the mRNA expression profiles of BL and EBV-immortalized cells (as PTLD model). Among the genes expressed at low level in BL cells, we have identified many genes involved in the NF-kappaB and interferon response that play a pivotal role in antigen presentation and immune recognition. Using a cell line in which EBNA2 and c-myc can be regulated at will, we show that c-MYC negatively regulates STAT1, the central player linking the Type-I and Type-II interferon response. Switching off c-myc expression leads to STAT1 induction through a direct and indirect mechanism involving induction of Type-I interferons. c-MYC thus masks an interferon-inducing activity in these cells. Our findings imply that immune escape of tumor cells is not only a matter of in vivo selection but may be additionally promoted by activation of a cellular oncogene.     

T cell response to Hu-D peptides in patients with anti-Hu syndrome

The anti-Hu syndrome is the most common paraneoplastic neurologic syndrome but the exact mechanism of immune mediated neuronal injury remains unknown. Anti-Hu antibodies do not appear to play a pivotal role in the pathogenesis of the disease. To assess cell-mediated immunity, we selected 51 peptides from the Hu-D sequence and tested their ability to bind to six common HLA class I molecules. Stable complexes with purified HLA molecules were obtained with 19/51 (37%) selected peptides. Subsequently, the ability of the 19 HLA-binding peptides to stimulate T cells from 10 patients and 10 control subjects was evaluated by detecting IFN- secretion. An anti-peptide T-cell response was observed in 7/10 Hu-positive patients but also in 3/10 control subjects. Overall, a significant T-cell activation occurred in response to 74% (14 out of 19) of the selected peptides in the Hu-positive patients vs. 16% (3 out of 19) in the control group (p < 0.001). In addition, T cells of patients tested within 3 months of the onset of anti-Hu syndrome responded to 82% (14 out of 17) of assessed Hu-D peptides vs. 37% (7 out of 19) in patients tested 1 year or more after developing the syndrome (p < 0.01). Thus, the present study suggests a role of cellular immunity during the course of anti-Hu syndrome.     

Microbiome changes in esophageal cancer: implications for pathogenesis and prognosis

Esophageal cancer(EC) is an aggressive malignancy with a poor prognosis. Various factors, including dietary habits, and antacid and antibiotic use, have been shown to influence the esophageal microbiome. Conversely, enrichment and diversity of the esophageal microbiome can also impact its function. Recent studies have revealed prevalent changes in the esophageal microbiome among patients with EC, thus suggesting the potential contribution of the esophageal microbiome to EC development. Additiona...     

Once-weekly dosing of recombinant human erythropoietin alpha in patients with myelodysplastic syndromes unresponsive to conventional dosing.

BACKGROUND: Once-weekly dosing of recombinant human erythropoietin (rhEPO) in patients with myelodysplastic syndromes (MDS) has not been investigated thoroughly. We performed a clinical trial to evaluate the effects of this new dosing regimen in patients with MDS who were unresponsive to the conventional three-times-weekly schedule. PATIENTS AND METHODS: Forty-eight patients with low- or intermediate-risk MDS were enrolled in a 12-week study. rhEPO alpha (rhEPOalpha) was administered once-weekly by subcutaneous injection with a starting dose of 40,000 U fixed dose. The drug dosage was increased to 60,000 U fixed dose if after 6 weeks there was no or suboptimal erythroid response. RESULTS: Clinically significant responses were seen in 13 (27%) patients, with 11 improving their response after dose escalation of rhEPOalpha. Only one patient (case 23) maintains a response after a follow-up period of 14 months. All other patients had responses lasting between 10 and 43 weeks, with a median time to relapse of 20 weeks. Treatment was well tolerated, with no relevant adverse events. Response to therapy was associated with significantly higher concentrations of circulating erythroid blast-forming units and a decrease of the bone marrow fraction of apoptic CD34+ cells. CONCLUSIONS: Once-weekly rhEPOalpha therapy results in an improvement of erythropoiesis in a subset of MDS patients who are unresponsive to conventional dosing, and may act by inhibiting apoptosis of erythroid precursors. These results warrant further investigation of this dosing regimen either alone or in combination with other agents.     

Prospective follow-up for malignant melanoma in patients with atypical-mole (dysplastic-nevus) syndrome

A total of 357 white patients who had melanocytic nevi that fulfilled the clinical criteria for the "classic" atypical-mole (dysplastic-nevus) syndrome (100 or more melanocytic nevi; one or more melanocytic nevi 8 mm or larger in diameter; and, one or more melanocytic nevi with atypical features) were followed for the development of cutaneous malignant melanomas. Seventeen patients (4.8%) developed malignant melanomas during an average follow-up period of 49 months. One patient developed two malignant melanomas. Eight of the malignant melanomas detected were in situ and ten were invasive melanomas (less than 0.86 mm in Breslow thickness), implying an excellent prognosis. The number of malignant melanomas detected in these patients exceeded significantly the number expected to occur in age- and sex-matched white controls. All groups were shown to have an increased risk for the development of malignant melanomas. Total-body photographs were helpful in detecting changes in size, shape, and color that led to the diagnosis of malignant melanoma. These data support the concept that patients with this readily regionalized clinical presentation of classic atypical-mole syndrome are at an increased risk for malignant melanomas and, therefore, should be examined regularly.     

Success of short-term,higher-dose imatinib mesylate to induce clinical response in FIP1L1-PDGFRα-negative hypereosinophilic syndrome

Presence of the oncogenic mutation FIP1L1-PDGFRα in hypereosinophilic patients is predictive of hematologic response to imatinib mesylate. However, most patients with hypereosinophilic syndrome (HES) do not have this mutation and have not responded to imatinib doses traditionally successful in patients who test positive for FIP1L1-PDGFRα. A patient with FIP1L1-PDGFRα-negative HES who had intolerance of interferon α-2b and hydroxyurea was treated with escalating doses of imatinib. At 800 mg of imatinib daily, eosinophilia was controlled, allowing prednisone tapering and control of clinical and laboratory-detected abnormalities. HES patients who test negative for FIP1L1-PDGFRα may benefit from a trial of higher-dose imatinib.     

Better prognosis for patients with del(7q) than for patients with monosomy 7 in myelodysplastic syndrome

BACKGROUND:

Abnormalities involving chromosome 7 are frequent in myelodysplastic syndrome (MDS) and suggest a poor prognosis.

METHODS:

The authors examined the hypothesis that the clinical features and survival associated with isolated deletion (del) of part of the long arm of chromosome 7 (7q) in MDS are different from those associated with isolated monosomy 7 (complete loss of chromosome 7). In total, 133 patients with a diagnosis of de novo MDS (according to the World Health Organization [WHO] classification) and chromosome 7 abnormalities in the Spanish MDS Registry were evaluated retrospectively. Four karyotypic groups were identified: isolated del(7q) (n = 29), isolated monosomy 7 (n = 27), del(7q) with additional abnormalities (n = 24), and monosomy 7 with additional abnormalities (n = 53).

RESULTS:

Isolated del(7q) was more frequent in patients with less advanced MDS according to the WHO classification or the International Prognostic Scoring System. In addition, isolated del(7q) was associated with fewer blasts in bone marrow than other cytogenetics groups. Survival was significantly superior in patients with isolated del(7) than in those with isolated monosomy 7, del(7q) with additional abnormalities, or monosomy 7 with additional abnormalities. On multivariate analysis, age, the percentage of blasts in bone marrow, and other chromosome 7 abnormalities apart from isolated del(7q) were identified as independent risk factors for survival.

CONCLUSIONS:

The current results demonstrated that patients who had MDS with isolated del(7q) had some distinct clinical‐pathologic characteristics as well as better survival than patients who had MDS with isolated monosomy 7. Cancer 2012;. © 2011 American Cancer Society.     

The hypereosinophilic syndrome associated with CD4+CD3- helper type 2 (Th2) lymphocytes.

We describe herein the clinical and laboratory manifestations of a unique group of patients (pts) presenting with hypereosinophilic syndrome (HES) who were treated in our medical centers for 4-13 years. Skin biopsies, flow cytometry of peripheral blood mononuclear cells (PBMC), assays for cytokines and immunoglobulin (Ig) production in vitro, and Southern blots of T-cell receptor (TCR) genes were performed. All four pts had a persistent hypereosinophilia (> 1.9 x 10(9)/L) and chronic skin rash. Three of four had elevated IgE, thrombotic manifestations and lung involvement (asthma and/or infiltrates), and one had deforming sero-negative arthritis of the hands. 66-95% of their peripheral T-cells expressed CD4 but not CD3 or TCR molecules on the cell surface membrane. Activated CD4+CD3- cells secreted interleukin (IL)-4 and/or 5, and were required for maximal IgE secretion by autologous B-cells. Two pts had evidence of rearrangement of TCR genes of the CD4+CD3- cells, one of whom died of anaplastic lymphoma. In conclusion, HES with CD4+CD3- lymphocytosis may be associated with high serum IgE, dermatological, pulmonary, thrombotic and rheumatic manifestations which may be due to Th2 effects of CD4+CD3- cells migrating to end organs. Fatal systemic lymphoid malignancy may also develop in some pts with monoclonal expansion of the CD4+CD3- T-cells.