Biomedical subjects

Dan Jones

Publications and source records attributed to Dan Jones.

At least 19 recordsLinked to original sources

PubMed2006

Abnormal expression of interleukin-23 in mycosis fungoides/Sézary syndrome lesions.

Progression of mycosis fungoides (MF) to Sézary syndrome (SS) is accompanied by a shift from a T(H)1 to a T(H)2 cytokine profile. Interleukin (IL)-23 is a novel cytokine that shares a common p40 subunit with the T(H)1 inducer, IL-12. IL-23 induces a third profile, T(H)IL-17, that is dominant in inflammation and autoimmunity. Although IL-23 induces an eczematous-like skin reaction in mice, and is expressed in T(H)1-mediated skin disorders such as psoriasis, it has not been evaluated in MF/SS. To study the role of IL-23 in MF/SS development, 40 MF/SS lesions of all stages were immunohistochemically analyzed with a novel anti-human IL-23 antibody raised against full-length human IL-23. IL-23 was detected with the catalyzed signal amplification system. The intensity and frequency of IL-23 staining were semi-quantitatively graded in both the dermal infiltrate and the epidermis. Increased expression of IL-23 was observed throughout the epidermal keratinocytes and in dermal lymphocytes compared to normal skin. IL-23 intensity did not differ significantly among the stages of MF/SS; however, in stage IVB patients, we observed lower frequency of IL-23 expression in dermal lymphocytes than in other stage patients [P = 0.13, analysis of variance (ANOVA)]. Interestingly, clusters of atypical lymphocytes, especially the epidermotropic tumor cells, demonstrated weak or absent IL-23 staining in 18 of 40 (45%) lesions. This finding was present in 4 of 5 (80%) of the stage IVB lesions and 7 of 11 (64%) of the lesions from Sézary patients. These findings indicate that abnormal IL-23 expression may play a role in the pathogenesis and progression of MF/SS.

Disease Progression↗

PubMed2006

Expression of the plasmacytoid dendritic cell marker BDCA-2 supports a spectrum of maturation among CD4+ CD56+ hematodermic neoplasms.

CD4+CD56+ hematodermic neoplasms are rare, aggressive hematopoietic malignancies usually presenting with cutaneous masses followed by a leukemic phase. The blastic morphology, CD56 expression and lack of definitive myeloid or T-cell markers initially resulted in assignment of this tumor to the NK-cell lineage. Accumulating evidence now suggests that these neoplasms represent malignant counterparts to the plasmacytoid dendritic cell. BDCA-2 is a cell surface protein whose expression is restricted to human plasmacytoid dendritic cells, in a differentiation stage-specific manner. In the current study, we assessed expression of BDCA-2 in CD4+CD56+ hematodermic neoplasms using a new antibody reagent we developed for use in fixed tissue sections. In 10 of 19 cases of CD4+CD56+ hematodermic neoplasm, BDCA-2 immunoreactivity was detected, whereas no expression was observed in NK-lineage tumors (0 of six). Interestingly, expression of terminal deoxynucleotidyl transferase, a marker of immaturity/blast stage, was significantly and negatively correlated with BDCA-2 in CD4+CD56+ hematodermic neoplasms whereas a positive correlation was observed between BDCA-2 and CD7. These findings demonstrate that BDCA-2 is expressed predominantly in the CD7+ subset of hematodermic neoplasms, and similar to non-neoplastic plasmacytoid dendritic cells, expression indicates a relatively more mature differentiation state. Clinical follow-up data confirm the aggressiveness of these tumors and suggests that BDCA-2 immunoreactivity, as identified here, may herald a significant reduction in survival.

Antigens, Neoplasm↗

PubMed2006

MK-0457, a novel kinase inhibitor, is active in patients with chronic myeloid leukemia or acute lymphocytic leukemia with the T315I BCR-ABL mutation.

MK-0457 (VX-680) is a small-molecule aurora kinase (AK) inhibitor with preclinical antileukemia activity. The T315I BCR-ABL mutation mediates resistance to imatinib, nilotinib, and dasatinib. MK-0457 has in vitro activity against cells expressing wild-type or mutated BCR-ABL, including the T315I BCR-ABL mutation. Three patients with T315I abl-mutated chronic myeloid leukemia (CML) or Philadelphia chromosome (Ph)-positive acute lymphocytic leukemia (ALL) have achieved clinical responses to doses of MK-04547 that are not associated with adverse events. Higher MK-0457 dose levels were associated with clinical responses and down-regulation of CrkL phosphorylation in leukemia cells. The possible role of AK inhibition in these clinical responses requires further investigation. The currently reported cases are the first observed clinical activity of a kinase inhibitor against the T315I phenotype. The observation of responses in 3 patients with T315I phenotype-refractory CML or Ph-positive ALL, at doses of MK-0457 associated with no significant extramedullary toxicity, is very encouraging.

Adaptor Proteins, Signal Transducing↗

PubMed2006

Dasatinib (BMS-354825) is active in Philadelphia chromosome-positive chronic myelogenous leukemia after imatinib and nilotinib (AMN107) therapy failure.

Developing strategies to counteract imatinib resistance constitutes a challenge in chronic myelogenous leukemia (CML). Therapy with the tyrosine kinase inhibitors nilotinib (AMN107) and dasatinib (BMS-354825) has produced high rates of hematologic and cytogenetic response. Src kinase activation has been linked to Bcr-Abl-mediated leukemogenesis and CML progression. In addition to binding Abl kinase with less stringent conformational requirements than imatinib, dasatinib is a potent Src kinase inhibitor. In the current study, we report on 23 patients with CML (19 of them in accelerated or blastic phases) treated with dasatinib after treatment failure with both imatinib and nilotinib. More than half (13; 57%) of 23 patients responded to dasatinib: 10 (43%) had a complete hematologic response (CHR), including 7 (30%) who had a cytogenetic response (2 complete, 4 partial, and 1 minor). These results suggest that dasatinib may be active in some patients after failure with both imatinib and nilotinib.

Adult↗

PubMed2006

t(3;21)(q26;q22) in myeloid leukemia: an aggressive syndrome of blast transformation associated with hydroxyurea or antimetabolite therapy.

BACKGROUND: The t(3;21)(q26;q22) translocation is associated with myeloid leukemias and results in a chimeric oncoprotein containing AML1/RUNX1 variably fused to EAP, MDS1, and/or EVI1. METHODS: The current study describes what to the authors' knowledge is the first large case series reported to date of 26 t(3;21)(q26;q22)-associated leukemias, in which 24 cases arose after chemotherapy. Conventional G-band karyotyping and flow cytometry immunophenotyping were performed. Reverse transcriptase-polymerase chain reaction (RT-PCR) was performed to detect fusion transcripts between AML1 and EAP, MDS1, or EVI1, followed by DNA sequencing. RESULTS: In all 16 patients with chronic myeloproliferative disorders, including 14 with chronic myelogenous leukemia (CML), the occurrence of t(3;21) heralded myeloid blast transformation. Fifteen (93%) patients had been previously treated with hydroxyurea. Eight patients with chronic myeloproliferative disorders (CMPD) were found to have t(3;21) with t(9;22) as the sole cytogenetic abnormality; in 5 other patients this was accompanied by trisomy 8. Among 10 cases of t(3;21)-associated acute myeloid leukemia, 8 were secondary tumors after chemotherapy for other neoplasms that had been treated with regimens including fludarabine and 5-fluorouracil in 3 patients each and etoposide in 2 patients. The immunophenotype of the blasts in all 22 tested cases was similar, with uniform expression of myeloid markers and CD34 and variable expression of CD7 and CD9, but minimal morphological myeloid maturation. Dysplastic micromegakaryocytes and bone marrow fibrosis were observed predominantly in CMPD cases. RT-PCR followed by DNA sequencing showed that the AML1-/MDS1-/EVI1 (AME) fusion transcript was detected in all 5 cases assessed. Among the patients with CMPD, 8 died of disease (at a median of 6.5 mos) and 5 achieved disease remission with bone marrow transplantation. Among patients with acute myeloid leukemia/myelodysplastic syndrome, 7 died of disease (at a median of 2 mos) and 2 had persistent leukemia with short follow-up. CONCLUSIONS: Activation of AME through t(3;21) defines a highly aggressive, therapy-related leukemic blast syndrome. Prior treatment with hydroxyurea or other antimetabolites is implicated as a contributory cause.

Adult↗

PubMed2006

Lenalidomide therapy in myelofibrosis with myeloid metaplasia.

We present results of 2 similarly designed but separate phase 2 studies involving single-agent lenalidomide (CC-5013, Revlimid) in a total of 68 patients with symptomatic myelofibrosis with myeloid metaplasia (MMM). Protocol treatment consisted of oral lenalidomide at 10 mg/d (5 mg/d if baseline platelet count < 100 x 10(9)/L) for 3 to 4 months with a plan to continue treatment for either 3 or 24 additional months, in case of response. Overall response rates were 22% for anemia, 33% for splenomegaly, and 50% for thrombocytopenia. Response in anemia was deemed impressive in 8 patients whose hemoglobin level normalized from a baseline of either transfusion dependency or hemoglobin level lower than 100 g/L. Additional treatment effects in these patients included resolution of leukoerythroblastosis (4 patients), a decrease in medullary fibrosis and angiogenesis (2 patients), and del(5)(q13q33) cytogenetic remission accompanied by a reduction in JAK2(V617F) mutation burden (1 patient). Grade 3 or 4 adverse events included neutropenia (31%) and thrombocytopenia (19%). We conclude that lenalidomide engenders an intriguing treatment activity in a subset of patients with MMM that includes an unprecedented effect on peripheral blood and bone marrow abnormalities.

Administration, Oral↗

PubMed2006

Allogeneic stem cell transplantation for patients with chronic myeloid leukemia and acute lymphocytic leukemia after Bcr-Abl kinase mutation-related imatinib failure.

Resistance to imatinib mesylate is an emerging problem in the treatment of chronic myeloid leukemia (CML), often associated with point mutations in the Bcr-Abl kinase domain. Outcome of patients with such mutations after allogeneic stem cell transplantation (Allo-SCT) is unknown. Ten imatinib-resistant patients with Bcr-Abl kinase mutations received a transplant: 9 had CML (3 in chronic phase, 4 in accelerated phase, and 2 in blast phase) and 1 had Philadelphia-positive acute lymphocytic leukemia (ALL). Patients harbored 9 different protein kinase mutations (T315I mutation, n = 2). Preparative regimens were ablative (n = 7) and nonablative (n = 3). All patients engrafted; there were no treatment-related deaths. Disease response was complete molecular (CMR; n = 7), major molecular (n = 2), and no response (n = 1). Three patients (mutations Q252H, E255K, and T315I) died of relapse after Allo-SCT. Seven patients are alive (6 in CMR) for a median of 19 months. Allo-SCT remains an important salvage option for patients who develop resistance to imatinib through Bcr-Abl mutations.

Adult↗

PubMed2006

Eradication of minimal residual disease in hairy cell leukemia.

Although the nucleoside analogs cladribine and pentostatin produce high response rates in patients with hairy cell leukemia (HCL), a significant number of patients eventually relapse. Several studies have demonstrated that patients with complete remission (CR) have a longer disease-free survival. Therefore, strategies to improve on the initial response to nucleoside analog therapy are likely to be beneficial, at least for a proportion of patients. We have treated 13 patients with newly diagnosed HCL (n = 11) or after failure of one prior chemotherapy (n = 2) with cladribine (5.6 mg/m(2) given intravenously over 2 hours daily for 5 days) followed by 8 weekly doses of rituximab (375 mg/m(2)). All patients achieved a CR and minimal residual disease (MRD) assessed by consensus primer polymerase chain reaction (PCR) or flow cytometry was eradicated in 11 (92%) of 12 and in 12 (92%) of 13 of patients, respectively. There was no decline in the absolute CD4 and CD8 lymphocyte number after rituximab. We conclude that eradication of MRD in HCL is possible. Whether this leads to a reduced risk of relapse would need to be evaluated in a larger number of patients and with longer follow-up. Disease characteristics may potentially be used to identify patients that are more likely to benefit from such additional therapy.

Adult↗

PubMed2006

Analytical performance and diagnostic accuracy of immunometric assays for the measurement of circulating oxidized LDL.

BACKGROUND: Oxidized LDL (ox-LDL) plays an important role in the pathogenesis of coronary heart disease (CHD). Several tests for circulating ox-LDL have been published. We believe it is critical to carefully evaluate these assays because small differences in performance may have profound effects when results are compared; we therefore compared the analytical and clinical performances of 2 assays: one developed in our laboratory and a commercial assay (Mercodia) that uses the same monoclonal antibody (4E6). METHODS: We determined the variance of ox-LDL in both tests, including its longitudinal stability (n = 225; 3 time points per person) and its diagnostic accuracy, by ROC analysis of 95 consecutive CHD patients and 20 controls. RESULTS: The between-person variability was 77% for the in-house assay (with the remaining 23% being within-person and analytical variance) and 74% for the commercial assay. For comparison, previously reported values were 66% for high-sensitivity C-reactive protein and 82% for total cholesterol. The areas under the curves for CHD in the 2 assays were identical (0.85). The odds ratios (logistic regression) for CHD among persons with high ox-LDL (>or=15 mg/L) compared with persons with low ox-LDL were not different: 4.3 (95% confidence interval, 1.4-12) for the in-house assay and 3.3 (1.1-10) for the commercial assay. CONCLUSIONS: The longitudinal stability of ox-LDL, as assessed by multiple measures in people over time, is similar to that of total cholesterol and high-sensitivity C-reactive protein. Both assays tested similarly distinguish between healthy controls and CHD patients.

Adult↗

PubMed2006

Cytogenetic anomalies in hyaline vascular Castleman disease: report of two cases with reappraisal of histogenesis.

The pathogenesis of hyaline vascular Castleman disease (HVCD) is poorly understood. Although generally considered reactive in nature, a subset of cases has been shown to harbor focal proliferations of stromal cells, such as follicular dendritic cell (FDC) and angiomyoid proliferations. We report two typical cases of HVCD with cytogenetic anomalies: one was t(1;22)(qter;q13) and the other was t(7;8)(q37.3;q12) in cultured stromal cells, as demonstrated by conventional cytogenetic analysis. The cultured cells were immunoreactive for smooth muscle actin but negative for CD21, CD31, and CD34, and ultrastructurally possessed thin filaments (5-7.5 nm) with dense bodies, and pinocytotic vesicles, characteristic of smooth muscle cells. The lack of monoclonality of lymphoid cells in lesional tissues by immunohistochemical and molecular analyses also supports the origin of these anomalies from the stromal cells, most likely myoid cells. Moreover, the absence of overt stromal proliferations suggests that cytogenetic changes in stromal cells of HVCD precede histologic evidence of stromal overgrowth, which may account for the occurrence of angiomyoid proliferations arising in some cases of HVCD. Further studies with more cases are needed to decipher whether part or even most of HVCD cases bear genetic changes in the beginning of the disease without morphologically stromal overgrowth.

Adult↗

PubMed2006

Tissue-specific function of lymph node fibroblastic reticulum cells.

OBJECTIVE: We present the first characterization of the cytokine expression pattern of lymph node fibroblastic reticulum cells (FRC), which are the stromal cells responsible for maintaining the highly structured nodal reticular fiber framework. METHODS: Microarray expression profiles of cultured nodal FRC and dermal fibroblasts (DF) were compared as well as their response to TNF, IL-4, IL-6 and IL-13, cytokines responsible for intranodal stromal activation. RESULTS: Hierarchical clustering of FRC and DF short-term culture samples revealed genes that were differentially expressed in FRC and DF. Identified differently regulated genes were confirmed by RNase protection analysis, PCR or immunohistochemistry. At earlier culture time points, FRC showed higher levels of several chemokines, including CCL2/MCP-1, and cytokines, e.g. IL-6, whereas several genes related to the production of extracellular matrix and angiogenesis were preferentially expressed in early DF cultures. By 60 days in culture, FRC and DF showed similar expression patterns consistent with homogenization of specialized stromal subsets. FRC and DF showed nearly identical transcriptional responses to exogenous TNF stimulation. CONCLUSIONS: Cultured FRC showed an overall transcriptional profile similar to cultured DF, including parallel responsiveness to TNF, but with differences in the expression of chemotactic chemokines, which reflect their biological roles.

Cells, Cultured↗

PubMed2006

Chronic myelomonocytic leukemia evolving from preexisting myelodysplasia shares many features with de novo disease.

The majority of chronic myelomonocytic leukemia (CMML) cases arise de novo; cases evolving from preexisting myelodysplasia (MDS) or myeloproliferative diseases have not been well-studied. We conducted the present study to determine the clinicopathologic features and to study possible underlying molecular and cytogenetic mechanisms involved in this evolution. Between April 1995 and November 2005, we identified 120 CMML cases, of which 20 (16.7%) had a previous diagnosis of MDS. Of the 20 patients with MDS, 6 had relative monocytosis at diagnosis. At the time of MDS to CMML evolution, mutations in JAK2 (V617F), FLT3 (ITD), K-ras-2, or N-ras were not acquired, and only 1 (6%) of 17 evaluable cases showed cytogenetic progression. The median time to evolution from MDS to CMML was 29 months, and the median survival following CMML development was 13 months. Three cases (17%) transformed to acute myeloid leukemia. These findings indicate that in some cases of otherwise typical MDS, the progenitor cells may have some capacity for monocytic proliferation at diagnosis and manifest rapid disease progression once a monocytic proliferation supervenes.

Aged↗

PubMed2006

Activating FLT3 mutations are detectable in chronic and blast phase of chronic myeloproliferative disorders other than chronic myeloid leukemia.

FLT3 gene mutations, either internal tandem duplication (ITD) or D835 point mutations, have been studied extensively in acute myeloid leukemia and myelodysplastic syndrome (MDS). Little is known about FLT3 mutations in chronic myeloproliferative diseases (CMPDs) or their relationship with V617F JAK2 mutations. We analyzed bone marrow samples from 142 patients with Philadelphia (Ph) chromosome- CMPD or CMPD/MDS and from 119 patients with Ph+ chronic myeloid leukemia (CML) using a multiplex polymerase chain reaction assay. FLT3 mutations, 11 ITD and 2 D835, were detected in 13 (9.2%) patients with CMPD or CMPD/MDS, 7 in blast phase and 6 in chronic phase. Analyses for JAK2 mutations in 11 of 13 cases were all negative. By contrast, no FLT3 mutations were detected in CML, including 108 chronic and 11 blast phase cases. FLT3 mutations occur in approximately 10% of CMPD and CMPD/MDS but are not observed in JAK2+ CMPD or in CML.

Blast Crisis↗

PubMed2006

Molecular approaches towards characterization, monitoring and targeting of viral-associated hematological malignancies.

Viral-associated malignancies usually arise in the setting of altered immunity or with declines in immune function associated with aging. The main culprits are the lymphotropic herpesvirus, including Epstein-Barr virus (EBV) and human herpesvirus-8, which are the focus of this review. Chronic persistent infection and viral reactivation are the main risk factors for development of herpesvirus-associated malignancies and have provided the rationale for intensive monitoring of viral loads in some clinical contexts. Quantitative detection of EBV levels in the post-transplant period and following treatment of EBV-associated malignancies now have a proven role in outcome prediction. Both T-cell immunotherapy and humoral immunotherapies directed against latent viral antigens represent promising interventional approaches to treatment of viral-associated malignancies.

Animals↗

PubMed2006

Atypical CD8+ cutaneous T-cell lymphoma after immunomodulatory therapy.

Systemic immunomodulatory agents have recently been approved for the treatment of rheumatoid arthritis and psoriasis. Although lymphomas are known to emerge in the setting of immunosuppressive therapy, it has not been well described or established for the newer biologic immune response modifiers. Herein, we describe 2 patients who developed unusual CD8+ cutaneous lymphoproliferative disorders after treatment with efalizumab and infliximab. The mechanisms and occurrence of lymphoma after immune response modifiers are discussed.

Antibodies, Monoclonal↗

PubMed2006

Lymphomas involving the pleura: a clinicopathologic study of 34 cases diagnosed by pleural biopsy.

CONTEXT: Pleural involvement by lymphoma is relatively common. However, there are very few clinicopathologic studies reported in the literature of lymphomas involving the pleura. OBJECTIVE: To characterize the clinicopathologic features of lymphomas involving the pleura. DESIGN: We reviewed the clinicopathologic features of 34 patients with lymphoma involving the pleura proven by biopsy and classified these neoplasms using the World Health Organization classification. RESULTS: There were 22 men and 12 women, with an average age of 62 years (range, 22-82 years). Nine (26.5%) patients had pleural involvement as the only site of disease, 22 (64.7%) had other sites of involvement, and 3 (8.8%) had inadequate staging data. Eighteen (56.2%) of 32 patients with adequate clinical data had a history of lymphoma (including 3 patients with pleural involvement as the only disease site). In 29 (85.3%) cases, a specific diagnosis according to the World Health Organization classification could be made: 17 (58.6%) diffuse large B-cell lymphoma, 5 (17.2%) follicular lymphoma (including a case with areas of diffuse large B-cell lymphoma), 2 (6.9%) small lymphocytic lymphomas/chronic lymphocytic leukemia, 2 (6.9%) precursor T-cell lymphoblastic lymphoma/leukemia, 1 (3.4%) mantle cell lymphoma, 1 (3.4%) posttransplant lymphoproliferative disorder, and 1 (3.4%) classical Hodgkin lymphoma. The other 5 cases were B-cell lymphomas that could not be further classified. Cytologic examination of pleural fluid was performed in 15 cases and was positive for lymphoma in 8 (53.3%) cases. CONCLUSIONS: Most patients with lymphoma involving the pleura have simultaneous evidence of systemic involvement. The most frequent type is diffuse large B-cell lymphoma, followed by follicular lymphoma. Cytologic examination can have negative results in patients with pleural involvement by lymphoma.

Adult↗

PubMed2006

Chronic myeloproliferative diseases with the t(5;12)(q33;p13): clonal evolution is associated with blast crisis.

Chronic myeloproliferative diseases (CMPDs) associated with t(5;12)(q33;p13) are reported to be responsive to imatinib mesylate. We studied 5 cases of CMPD with isolated t(5;12) treated at our hospital between January 1993 and October 2004. All were men with a median age of 55 years (range, 18-68 years). In the peripheral blood, each had marked leukocytosis, with variable eosinophilia (n = 4), monocytosis (n = 3), or basophilia (n = 2). Bone marrow specimens were hypercellular (70%-100%) with marked myeloid hyperplasia in each patient, but only 1 patient had eosinophilia, monocytosis, and basophilia. Follow-up ranged from 23 to 182 months (median, 48 months). Four died 23 to 182 months after initial diagnosis, 3 of blast crisis and 1 of cardiac complications of severe eosinophilia. Additional cytogenetic aberrations were identified at the time of blast crisis. Of 3 patients treated with imatinib, 2 responded, but only 1 had a sustained response. CMPD with t(5;12) commonly transforms to blast phase, and transformation is associated with cytogenetic evidence of clonal evolution.

Adolescent↗

PubMed2005

Use of all-trans retinoic acid plus arsenic trioxide as an alternative to chemotherapy in untreated acute promyelocytic leukemia.

We examined whether combining all-trans retinoic acid (ATRA) and arsenic trioxide (ATO) might be an alternative to ATRA plus chemotherapy in untreated acute promyelocytic leukemia (APL). Twenty-five low-risk patients (white blood cell [WBC] count less than 10 x 10(9)/L [10,000/microL]) received ATRA (45 mg/m(2) daily) and ATO (0.15 mg/kg daily, beginning day 10 of ATRA), and in complete remission (CR) received ATO plus ATRA, without chemotherapy, unless they were reverse transcriptase-polymerase chain reaction (RT-PCR)-positive 3 months from CR date or had molecular relapse. Nineteen high-risk patients were treated identically, but received chemotherapy, generally 9 mg/m(2) gemtuzumab ozogamycin (GO) on day 1 of induction. The CR rate was 39 of 44 (24 of 25 in low-risk, 15 of 19 in high-risk). Disease recurred at 9, 9, and 15 months, respectively, in 3 high-risk patients. The median follow-up time from CR date in the 36 patients alive in first CR is 16 months (15 months in low-risk, 20 months in high-risk), with 9 patients followed for at least 24 months. Each of the 36 patients was PCR-negative at last follow-up. Thus, none of the low-risk patients has received chemotherapy, and only 3 high-risk patients (the 3 with relapsed disease) have received chemotherapy past induction. ATRA plus ATO may serve as an alternative to chemotherapy in low-risk untreated APL (eg, in older patients) and, when combined with GO, may improve outcome in high-risk patients.

Aged↗