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Neil E Kay

Publications and source records attributed to Neil E Kay.

At least 19 recordsLinked to original sources
PubMed2006

Prospective evaluation of clonal evolution during long-term follow-up of patients with untreated early-stage chronic lymphocytic leukemia.

PURPOSE: Retrospective studies suggest cytogenetic abnormalities detected by interphase fluorescent in situ hybridization (FISH) can identify patients with chronic lymphocytic leukemia (CLL) who will experience a more aggressive disease course. Other studies suggest that patients may acquire chromosome abnormalities during the course of their disease. There are minimal prospective data on the clinical utility of the widely used hierarchical FISH prognostic categories in patients with newly diagnosed early-stage CLL or the frequency of clonal evolution as determined by interphase FISH. PATIENTS AND METHODS: Between 1994 and 2002, we enrolled 159 patients with previously untreated CLL (83% Rai stage 0/I) on a prospective trial evaluating clonal evolution by FISH. Patients provided baseline and follow-up specimens for FISH testing during 2 to 12 years. RESULTS: Chromosomal abnormalities detected by FISH at study entry predicted overall survival. Eighteen patients experienced clonal evolution during follow-up. The rate of clonal evolution increased with duration of follow-up with only one occurrence in the first 2 years (n = 71; 1.4%) but 17 occurrences (n = 63; 27%) among patients tested after 5+ years. Clonal evolution occurred among 10% of ZAP-70-negative and 42% of ZAP-70-positive patients at 5+ years (P = .008). CONCLUSION: This clinical trial confirms prospectively that cytogenetic abnormalities detected by FISH can predict overall survival for CLL patients at the time of diagnosis, but also suggests that many patients acquire new abnormalities during the course of their disease. Patients with higher ZAP-70 expression may be more likely to experience such clonal evolution. These findings have important implications for both clinical management and trials of early treatment for patients with high-risk, early-stage CLL.

Adult↗
PubMed2006

Combination chemoimmunotherapy with pentostatin, cyclophosphamide, and rituximab shows significant clinical activity with low accompanying toxicity in previously untreated B chronic lymphocytic leukemia.

Building on the prior work of use of pentostatin in chronic lymphocytic leukemia (CLL), we initiated a trial of combined pentostatin (2 mg/m2), cyclophosphamide (600 mg/m2), and rituximab (375 mg/m2) for 65 symptomatic, previously untreated patients. Of 64 evaluable patients, 34 (53%) were high Rai risk, 71% were nonmutated for the immunoglobulin heavy-chain variable region gene, 34% were CD38+, and 34% were ZAP-70+. Thirty patients (52%) had one anomaly detected by fluorescence in situ (FISH) hybridization, and 21 (36%) had complex FISH defects. Thirty-eight patients (58%) had grade 3+ hematologic toxicity but minimal transfusion needs and no major infections. Responses occurred in 58 patients (91%), with 26 (41%) complete responses (CRs), 14 (22%) nodular partial responses (nodular PRs), and 18 (28%) partial responses (PRs). Many patients with a CR also lacked evidence of minimal residual disease by 2-color flow cytometry. Examination of prognostic factors demonstrated poor response in the 3 patients with del(17p). In contrast, we found this regimen was equally effective in young versus older (>70 years) patients and in del(11q22.3) versus other favorable prognostic factors. Thus, this novel regimen of pentostatin, cyclophosphamide, and rituximab for previously untreated patients with CLL demonstrated significant clinical activity despite poor risk-based prognoses, achievement of minimal residual disease in some, and modest toxicity.

Adult↗
PubMed2006

Narrative review: initial management of newly diagnosed, early-stage chronic lymphocytic leukemia.

Chronic lymphocytic leukemia is one of the most common malignant lymphoid diseases in the western world and is frequently diagnosed by internists. There have been clinically significant changes in method of diagnosis, prognostic tools, supportive care, and treatment over the past 2 decades. Most patients with chronic lymphocytic leukemia now have Rai stage 0 or I disease at diagnosis. Patients with early-stage disease are a heterogeneous group: Approximately 30% to 50% will have accelerated disease progression, and the remainder may live for decades and possibly never require therapy. Recent insights into the biological characteristics of leukemic B cells have led to the discovery of new prognostic tools (immunoglobulin variable-region heavy chain gene mutation status, cytogenetic abnormalities assessed by fluorescent in situ hybridization, and Z-chain-associated protein kinase-70 protein expression) that can identify patients with early-stage disease who are at high risk for early disease progression. These tools allow physicians to individualize counseling, follow-up, and management on the basis of disease risk. In addition, new treatments developed over the past 2 decades (purine nucleoside analogues, monoclonal antibodies, and combination chemoimmunotherapy regimens) have dramatically improved response rates and appear to prolong survival. In this review, the authors discuss the current work-up of lymphocytosis and highlight how to use recently identified prognostic tools to stratify risk in patients with newly diagnosed, early-stage chronic lymphocytic leukemia. Recommendations for patient counseling, follow-up, supportive care, and initial treatment are presented for each risk category.

Biomarkers↗
PubMed2006

Complete response in multiple myeloma: clinical trial E9486, an Eastern Cooperative Oncology Group study not involving stem cell transplantation.

BACKGROUND: The importance of obtaining a complete response (CR) in multiple myeloma (MM) treated with chemotherapy is unclear. METHODS: The Eastern Cooperative Oncology Group evaluated 653 previously untreated patients with active MM randomized to vincristine, carmustine (BCNU), melphalan, cyclophosphamide, and prednisone (VBMCP), to VBMCP and recombinant interferon alfa-2 (INFalpha-2), or to VBMCP and high-dose cyclophosphamide. RESULTS: Objective response was achieved in 420 (67%) of the 628 eligible patients, and 85 (14%) achieved a CR. Patients receiving VBMCP and recombinant INFalpha-2 had a significantly higher CR (18%) than those receiving VBMCP alone (10%) (P = .02). The CR rate for VBMCP and high-dose cyclophosphamide was 12%. Median duration of survival was 3.5 years for all eligible patients, and the estimated 5-year survival rate was 31%. The median duration of survival from the date of objective response was 5.1 years for those who achieved a CR and 3.3 years for those with a partial response (P < .0001). The median postresponse survival was 6.6 years in the 21 patients in CR with nonclonal disease and 4.4 years in the 11 patients in CR who had persistent clonal disease. All patients with negative immunofixation results and nonclonal plasma cells in whom polymerase chain reaction was performed had a positive result (presence of tumor DNA). CONCLUSION: Patients in whom a CR was achieved had a longer survival than those who had a partial response.

Adult↗
PubMed2006

Metaphase cells with normal G-bands have cryptic interstitial deletions in 13q14 detectable by fluorescence in situ hybridization in B-cell chronic lymphocytic leukemia.

Interphase fluorescence in situ hybridization (FISH) studies with D13S319 show that deletions of 13q14 are common in B-cell chronic lymphocytic leukemia (B-CLL). In contrast, conventional cytogenetic studies in B-CLL seldom reveal abnormalities of chromosome 13. We hypothesized that chromosome 13 anomalies might not be detected because they are caused by cryptic deletions rather than by the absence of dividing B-CLL cells. To investigate this possibility, we used FISH with D13S319 to study metaphases from 12 patients known to have 13q- by interphase FISH. These same patients had normal chromosomes by conventional cytogenetic studies. As a result of this study, we report evidence that B-CLL metaphases with 13q- are not detected because these deletions are often cryptic and not visible by standard G-banding.

Aged↗
PubMed2006

Elevated serum B-lymphocyte stimulator levels in patients with familial lymphoproliferative disorders.

PURPOSE: Serum B-lymphocyte stimulator (BLyS) levels have been found to be elevated in a number of immune disease models. Therefore, we sought to establish whether BLyS levels were elevated in patients with B-cell lymphoproliferative disorders and to determine whether elevated BLyS levels correlated with clinical characteristics of the disease. PATIENTS AND METHODS: Specimens were collected from the peripheral blood of individuals diagnosed with B-cell chronic lymphocytic leukemia (B-CLL; n = 70) or from age- and sex-matched patients seen at the same institution (n = 41). Serum BLyS levels were determined by enzyme-linked immunosorbent assay, and sequencing of the BLyS promoter was performed by conventional methods and confirmed by restriction fragment length polymorphism analysis. RESULTS: We found that elevated BLyS levels were more common in patients with familial B-CLL than individuals with sporadic B-CLL or normal controls. Because of this association, we sequenced the BLyS promoter in patients with B-CLL and normal controls and identified a polymorphic site, -871 C/T. We found that the wild-type sequence was significantly underrepresented in patients with familial B-CLL (4%) compared with patients with sporadic B-CLL (30%; P = .01) or controls (24%; P = .04). Furthermore, using a luciferase reporter under control of the BLyS promoter containing either a C or a T at position -871, we found that the reporter construct containing a T at -871 had a 2.6-fold increase in activity (P = .004). CONCLUSION: Our data suggest serum BLyS levels are elevated in patients with familial B-CLL and that elevated BLyS levels correlate with the presence of a T at -871 in the BLyS promoter.

Adult↗
PubMed2006

Loss of TP53 is due to rearrangements involving chromosome region 17p10 approximately p12 in chronic lymphocytic leukemia.

Loss of tumor protein 53 (TP53) has been associated with aggressive disease and poor response to therapy in B-cell chronic lymphocytic leukemia (B-CLL). TP53 is located at chromosome band 17p13 and its absence can be detected by fluorescence in situ hybridization (FISH) in the interphase nuclei of 8-10% patients with B-CLL. To study the cytogenetic mechanism for loss of TP53, metaphase and interphase FISH studies were conducted on 16 B-CLL patients to investigate 17p10 to 17p12, a chromosome region known to be rich in low-copy DNA repeats. Loss of TP53 was caused by an isochromosome with breakpoints between 17p10 and 17p11.2 in four patients, an unbalanced translocation involving 17p10 to 17p11.2 in nine patients, and an unbalanced translocation involving 17p11.2 to 17p12 in three patients. These findings indicate that loss of TP53 results from the absence of nearly the entire chromosome 17 p-arm rather than to monosomy 17 or deletions of TP53. Translocations or isochromosome formations at sites of low-copy DNA repeats in 17p10 to 17p12 appear to be the mechanism for the loss of TP53 in B-CLL.

Aged↗
PubMed2006

Purine analogue-based chemotherapy regimens for patients with previously untreated B-chronic lymphocytic leukemia.

B-cell chronic lymphocytic leukemia (B-CLL) is a clonal malignancy characterized by the expansion of small B lymphocytes and accumulation of CLL cells. This disease is the most common form of leukemia in the Western hemisphere and is currently not considered to be curable using currently available therapies. Published reports have suggested that purine analogues have activity in B-CLL and superior to alkylating agents. Even though responses have been observed with purine analogues that are used as single agents, these responses were not durable. The use of combination purine analogue therapy with alkylating agents and/or monoclonal antibodies was then explored in order to take advantage of synergistic actions of these agents to improve the quality of clinical responses. Both fludarabine and pentostatin have shown improved responses when combined with alkylating agents and even higher overall and complete responses (CRs) when combined with monoclonal antibodies.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2006

The clinical and biologic importance of neovascularization and angiogenic signaling pathways in chronic lymphocytic leukemia.

Angiogenesis has been found to be an important regulator in the growth and metastasis of solid tumors. More recent studies have also demonstrated the importance of this biologic process in normal hematopoietic cell development and the pathophysiology of several hematologic malignancies. This review provides an overview of the clinical and biologic importance of angiogenesis in chronic lymphocytic leukemia (CLL). Patients with CLL have detectable levels of both plasma and cellular pro- and anti-angiogenic cytokines, as well as abnormal neovascularization in the marrow and lymph nodes. Recent evidence suggests a vascular endothelial growth factor (VEGF)-based autocrine pathway promotes the survival of CLL B cells in part through upregulation of anti-apoptotic proteins. Additionally, interactions between CLL B cells and their microenvironment generate alterations in the secretion of angiogenic factors that result in enhanced leukemic B-cell resistance to apoptotic cell death. From a clinical standpoint, interpatient variation is observed in markers of angiogenesis and appears to have prognostic implications. Several clinical trials evaluating the efficacy of anti-angiogenic agents for treatment of patients with CLL are underway with promising preliminary results. Additional research is needed to identify the regulation of aberrant and critical angiogenic pathways in CLL B cells, to determine how angiogenic markers can be used to improve prognostication for CLL patients, and to explore how the angiogenic characteristics of CLL B cells can best be manipulated for therapeutic benefit.

Angiogenesis Inducing Agents↗
PubMed2006

Update on risk-stratified management for chronic lymphocytic leukemia.

Major recent advances in understanding the biology of chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL) have improved clinical evaluation and influenced treatment decisions. CLL can be diagnosed early and accurately, and biological measurements can be used to predict a prognosis at diagnosis. Individual patient care can be risk stratified to optimize benefit and minimize complications of therapy. Purine analogs and monoclonal antibodies have markedly improved the efficacy of initial therapy but are not curative. The treatment of relapsed and refractory CLL is less successful. However, recent developments suggest that allogeneic stem cell transplant could have a larger role in a selected group of these patients. Potential new treatment modalities include targeted molecules that interrupt key components of CLL cell survival pathways, and active and passive immunotherapy. The management of CLL is in a dynamic phase of rapid evolution. Risk stratification using biological prognostic markers can improve current patient care and direct future clinical research.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2006

Cytotoxic synergy between the multikinase inhibitor sorafenib and the proteasome inhibitor bortezomib in vitro: induction of apoptosis through Akt and c-Jun NH2-terminal kinase pathways.

This study was undertaken to characterize preclinical cytotoxic interactions for human malignancies between the multikinase inhibitor sorafenib (BAY 43-9006) and proteasome inhibitors bortezomib or MG132. Multiple tumor cell lines of varying histiotypes, including A549 (lung adenocarcinoma), 786-O (renal cell carcinoma), HeLa (cervical carcinoma), MDA-MB-231 (breast), K562 (chronic myelogenous leukemia), Jurkat (acute T-cell leukemia), MEC-2 (B-chronic lymphocytic leukemia), and U251 and D37 (glioma), as well as cells derived from primary human glioma tumors that are likely a more clinically relevant model were treated with sorafenib or bortezomib alone or in combination. Sorafenib and bortezomib synergistically induced a marked increase in mitochondrial injury and apoptosis, reflected by cytochrome c release, caspase-3 cleavage, and poly(ADP-ribose) polymerase degradation in a broad range of solid tumor and leukemia cell lines. These findings were accompanied by several biochemical changes, including decreased phosphorylation of vascular endothelial growth factor receptor-2, platelet-derived growth factor receptor-beta, and Akt and increased phosphorylation of stress-related c-Jun NH2-terminal kinase (JNK). Inhibition of Akt was required for synergism, as a constitutively active Akt protected cells against apoptosis induced by the combination. Alternatively, the JNK inhibitor SP600125 could also protect cells from apoptosis induced by the combination, indicating that both inhibition of Akt and activation of JNK were required for the synergism. These findings show that sorafenib interacts synergistically with bortezomib to induce apoptosis in a broad spectrum of neoplastic cell lines and show an important role for the Akt and JNK pathways in mediating synergism. Further clinical development of this combination seems warranted.

Antineoplastic Agents↗
PubMed2006

Chronic lymphocytic leukemia: current and emerging treatment approaches.

In the last decade, advances in the treatment of patients with chronic lymphocytic leukemia (CLL) have improved responses and survival outcomes dramatically. Chlorambucil had been the cornerstone of treatment for decades. Now, treatment approaches typically include a purine nucleoside analog, such as fludarabine, in combination with immunotherapy, most commonly rituximab but also alemtuzumab. Several clinical trials of patients with untreated CLL have reported overall response rates as high as 95% with chemoimmunotherapy. Combinations include fludarabine, cyclophosphamide, and rituximab (FCR); pentostatin, cyclophosphamide, and rituximab; fludarabine and rituximab; and fludarabine and alemtuzumab. FCR has demonstrated complete response rates of 70% as frontline therapy. In addition, molecular prognostic indicators, such as IgVH mutational status, ZAP-70 expression, and chromosomal mutations (trisomy 12; 17p, and 11q deletions) are proving useful in identifying patients with poor-risk disease. Furthermore, advanced technologies such as polymerase chain reaction and flow cytometry can be used to detect minimal residual disease with increasing sensitivity. Elimination of minimal residual disease has been linked to improved survival and become an important clinical goal. While overall response rates with current chemotherapy treatments are superior to those seen with single agents (eg, chlorambucil), many CLL patients still fall short of achieving a complete response. Novel agents with unique, nonoverlapping mechanisms of action (eg, oblimersen sodium, lenalidomide, HuMax-CD20, GX15-070), and other treatments are under investigation in an attempt to further improve outcomes.

Alemtuzumab↗
PubMed2005

Protein expression profiling of CLL B cells using replicate off-line strong cation exchange chromatography and LC-MS/MS.

In this study we use replicate 2D-LC-MS/MS analyses of crude membranes from B cells derived from a patient with chronic lymphocytic leukemia (CLL) to examine the protein expression profile of CLL B cells. Protein identifications made by replicate 2D-LC-MS/MS analysis of tryptic peptides from detergent solubilized B cell membrane proteins, as well as replicate LC-MS/MS analysis of single off-line strong cation exchange chromatography (SCX) fractions, were analyzed. We show that despite the variance in SCX, capillary LC, and the data-dependent selection of precursor ions, an overlap of 64% between proteins identified in replicate runs was achieved for this system.

Antigens, CD↗
PubMed2005

A recombinant IL-4-Pseudomonas exotoxin inhibits protein synthesis and overcomes apoptosis resistance in human CLL B cells.

We have determined that CLL B cells consistently express type 3 membrane receptors for the Th2-derived cytokine IL-4 (IL-4R). Furthermore, when added to CLL B cells, IL-4 induces increased apoptosis resistance, increased protein synthesis in CLL B cells and rapid onset activation of STAT1, STAT5 and STAT6. Since the IL-4-IL-4R pathway is intact in CLL B cells and is related to apoptosis resistance, we considered whether we could target this pathway. A recombinant IL-4 Pseudomonas exotoxin fusion protein (IL-4 PE), known to bind to IL-4R, was incubated with CLL B cells. IL-4 PE (10 ng/ml) cultured with CLL B cells resulted in an increase of apoptosis/death from mean levels of 46.6+/-7.0 of non-exposed cells to 69+/-8.6 (n=6). By measuring in vitro protein synthesis, two predominant patterns of sensitivity were observed. In one, CLL B cell clones (n=4) were found to be extremely sensitive to IL-4 PE (IC50's range=6-25 ng/ml). In the second, low concentrations of IL-4 PE induced agonist activity while increasing concentrations induced cytotoxicity in 6 of 21 patient-derived cells. These studies suggest that the IL-4R, on B-CLL cells, can serve as a unique molecular target for directing cytotoxic agents in the therapy of B-CLL.

Apoptosis↗
PubMed2005

Fluorescent-labeled DNA probes applied to novel biological aspects of B-cell chronic lymphocytic leukemia.

Fluorescent-labeled DNA probes were used to study 52 chronic lymphocytic leukemia (B-CLL) patients for (1) disease progression, (2) angiogenesis genes, (3) T-cell leukemia 1 gene (TCL1), (4) immunoglobulin heavy chain variable region (IGHv) and (5) chromosome 6q. Compared to stable disease, more patients with progressive disease had > or =2 anomalies and a high percentage of neoplastic nuclei. Anomalies of genes for basic fibroblast growth factor, interleukin 4, vascular endothelial growth factor or TCL1 were not detected. Deletions in IGHv occurred in 25% of patients and correlated with IGHv gene expression. Probes for 6q23 detected more deletions in 6q than probes for 6q21.

Adult↗
PubMed2004

Adaphostin-induced apoptosis in CLL B cells is associated with induction of oxidative stress and exhibits synergy with fludarabine.

B-cell chronic lymphocytic leukemia (CLL) is characterized by accumulation of clonal lymphocytes resistant to apoptosis. We evaluated the ability of the investigational antileukemic agent adaphostin to induce apoptosis in CLL B cells and synergize with fludarabine in vitro. Analysis by annexin V/propidium iodide (PI) staining revealed that the concentration of adaphostin required to induce 50% cell death (IC50) at 24 hours was 4.2 microM (range, 1.10-11.25 microM; median, 4.25 microM; n=29) for CLL isolates and more than 10 microM for B and T cells from healthy donors. Immunoblots demonstrated adaphostin induced poly(adenosine diphosphate-ribose) polymerase (PARP) cleavage and cleavage of caspase-3 substrates, suggesting that adaphostin induces apoptosis. Adaphostin increased the level of reactive oxygen species (ROS) within CLL B cells, and the antioxidant N-acetylcysteine blocked both adaphostin-induced ROS generation and apoptosis. Adaphostin also caused a decrease in the level of the antiapoptotic protein Bcl-2. When adaphostin was combined with fludarabine (F-ARA-AMP), a synergistic effect on cell death was observed in all 10 CLL samples. These findings not only indicate that adaphostin induces apoptosis selectively in CLL B cells through a mechanism that involves ROS generation but also demonstrate its ability to augment the effects of fludarabine. Further preclinical development of adaphostin as a novel agent for the treatment of CLL appears warranted.

Adamantane↗