scholarly journals Novel ex vivo analysis of nonclassical, pleiotropic drug resistance and collateral sensitivity induced by therapy provides a rationale for treatment strategies in chronic lymphocytic leukemia

Blood ◽  
1996 ◽  
Vol 87 (5) ◽  
pp. 1962-1971 ◽  
Author(s):  
AG Bosanquet ◽  
PB Bell
Keyword(s):  
Drug Resistance ◽  
Chronic Lymphocytic Leukemia ◽  
Ex Vivo ◽  
Alkylating Agents ◽  
Treatment Strategies ◽  
Lymphocytic Leukemia ◽  
Cytotoxic Agents ◽  
Differential Staining ◽  
Pleiotropic Drug Resistance ◽  
Previously Treated

Abstract Extensive research into mechanisms of cytotoxic drug resistance and subsequent clinical trials of drug resistance modifiers have produced few encouraging results. In this report, we analyze 4,400+ ex vivo Differential Staining Cytotoxicity (DiSC) assay drug response results from patients with chronic lymphocytic leukemia (CLL) to investigate the development of drug resistance during treatment. Patients were untreated (n = 216) or previously treated with various cytotoxic agents (n = 188). Data was processed to identify ex vivo resistance (or sensitivity) induced by treating patients with prednisolone, chlorambucil, cyclophosphamide, anthracycline, or fludarabine. Induced resistance was apparently not associated with any one known mechanism. Treatment with chlorambucil induced a 10-fold sensitivity to steroids; cyclophosphamide induced greater resistance to anthracyclines than alkylating agents; anthracyclines induced greatest resistance to chlorambucil, cisplatin, carboplatin, and cladribine. Patients previously treated with at least two regimens were only 2.16-fold more resistant to CLL drugs than untreated patients, but had significantly reduced survival (median survival, 7.9 months compared with 61.1 months for untreated patients). These results suggest that chlorambucil and/or an antimetabolite should be administered before cyclophosphamide or anthracyclines to delay the onset of extensive pleiotropic drug resistance. Because individual differences in drug sensitivity are considerable, specific guidance could be obtained from ex vivo assay results. Furthermore, as a model for investigating drug resistance mechanisms, fresh CLL lymphocytes represent a useful alternative to drug-resistant cell lines.

Novel ex vivo analysis of nonclassical, pleiotropic drug resistance and collateral sensitivity induced by therapy provides a rationale for treatment strategies in chronic lymphocytic leukemia

Blood ◽  
1996 ◽  
Vol 87 (5) ◽  
pp. 1962-1971 ◽  
Author(s):  
AG Bosanquet ◽  
PB Bell
Keyword(s):  
Drug Resistance ◽  
Chronic Lymphocytic Leukemia ◽  
Ex Vivo ◽  
Alkylating Agents ◽  
Treatment Strategies ◽  
Lymphocytic Leukemia ◽  
Cytotoxic Agents ◽  
Differential Staining ◽  
Pleiotropic Drug Resistance ◽  
Previously Treated

Extensive research into mechanisms of cytotoxic drug resistance and subsequent clinical trials of drug resistance modifiers have produced few encouraging results. In this report, we analyze 4,400+ ex vivo Differential Staining Cytotoxicity (DiSC) assay drug response results from patients with chronic lymphocytic leukemia (CLL) to investigate the development of drug resistance during treatment. Patients were untreated (n = 216) or previously treated with various cytotoxic agents (n = 188). Data was processed to identify ex vivo resistance (or sensitivity) induced by treating patients with prednisolone, chlorambucil, cyclophosphamide, anthracycline, or fludarabine. Induced resistance was apparently not associated with any one known mechanism. Treatment with chlorambucil induced a 10-fold sensitivity to steroids; cyclophosphamide induced greater resistance to anthracyclines than alkylating agents; anthracyclines induced greatest resistance to chlorambucil, cisplatin, carboplatin, and cladribine. Patients previously treated with at least two regimens were only 2.16-fold more resistant to CLL drugs than untreated patients, but had significantly reduced survival (median survival, 7.9 months compared with 61.1 months for untreated patients). These results suggest that chlorambucil and/or an antimetabolite should be administered before cyclophosphamide or anthracyclines to delay the onset of extensive pleiotropic drug resistance. Because individual differences in drug sensitivity are considerable, specific guidance could be obtained from ex vivo assay results. Furthermore, as a model for investigating drug resistance mechanisms, fresh CLL lymphocytes represent a useful alternative to drug-resistant cell lines.

ROS-Mediated Upregulation of Noxa Overcomes Drug-Resistance Due to P53-Dysfunction in Chronic Lymphocytic Leukemia.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 2382-2382
Author(s):  
Sanne H. Tonino ◽  
Jacoline M van Laar ◽  
Marinus H. J. van Oers ◽  
Jean Y.J. Wang ◽  
Eric Eldering ◽  
...  
Keyword(s):  
Drug Resistance ◽  
Cell Death ◽  
Chronic Lymphocytic Leukemia ◽  
Combination Treatment ◽  
Conflicts Of Interest ◽  
Alkylating Agents ◽  
Single Agent ◽  
Treatment Strategies ◽  
Cd40 Ligand ◽  
Lymphocytic Leukemia

Abstract Abstract 2382 Poster Board II-359 Although recent advances in treatment-strategies for chronic lymphocytic leukemia (CLL) have resulted in increased remission rates and response duration, the disease eventually relapses, which necessitates repeated cycles of therapy. Eventually most patients develop chemo-resistant disease which infers a very poor prognosis. The activity of purine-analogs and alkylating agents, the backbone of current treatment regimens, depends on functional p53 and chemo-resistance is highly associated with a dysfunctional p53-response. P53-independent sensitization of CLL cells to these compounds could represent a novel strategy to overcome chemo-resistance. Platinum-based compounds have been successfully applied in relapsed lymphoma and recently also in high-risk CLL. In various cancer-types, the activity of such compounds has been found to be p53-independent and in part mediated by p73. In this study we investigated the efficacy and mechanism of action of platinum-based compounds in chemo-refractory CLL. Neither cisplatinum nor oxaliplatin as a single agent induced cell death in clinically relevant doses. However, independent of p53-functional status, platinum-based compounds acted synergistically with fludarabine, which was found to be caspase-dependent. Combination-treatment resulted in strong upregulation of the pro-apoptotic BH3-only protein Noxa. We did not find evidence for a role of p73; however, the observed synergy was found to involve generation of reactive oxygen species (ROS). Co-treatment with ROS-scavengers completely abrogated Noxa-upregulation and cell-death upon combination treatment in p53-dysfunctional CLL. Noxa RNA-interference markedly decreased sensitivity to combination treatment, supporting a key role for Noxa as mediator between ROS signaling and apoptosis induction. In addition to these findings, we tested the effects of platinum-based compounds and fludarabine on drug-resistance resulting from CD40-ligand stimulation of CLL cells, which represents a model for CLL cells in the protective micro-environment of the secondary lymph node-tissue (Hallaert et al Blood 2008 112(13):5141). Combination treatment could overcome CD40-ligand induced chemo-resistance and was, at least in part, mediated by the generation of ROS and marked induction of expression of Noxa. Our data indicate that interference with the cellular redox-balance represents an interesting target to overcome drug resistance due to both p53-dysfunction as well as micro-environmental protective stimuli in CLL. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Long-term follow-up of patients with chronic lymphocytic leukemia treated with fludarabine as a single agent

Blood ◽  
1993 ◽  
Vol 81 (11) ◽  
pp. 2878-2884 ◽  
Author(s):  
MJ Keating ◽  
S O'Brien ◽  
H Kantarjian ◽  
W Plunkett ◽  
E Estey ◽  
...  
Keyword(s):  
Chronic Lymphocytic Leukemia ◽  
Clinical Response ◽  
Alkylating Agents ◽  
Single Agent ◽  
Response To Therapy ◽  
Lymphocytic Leukemia ◽  
Strongly Correlated ◽  
Prior Therapy ◽  
Previously Treated

Abstract The clinical response and survival of 113 patients with at least 3-year follow-up after treatment with fludarabine as a single agent for chronic lymphocytic leukemia has been evaluated. Seventy-eight patients were previously treated and 35 were untreated. The response to therapy and survival were strongly correlated with the degree of previous therapy, the stage of disease, and whether or not the patients were refractory to alkylating agents. Other characteristics associated with survival were the age of the patient and the serum albumin level at the start of therapy. The median time to progression of responders who had not received prior therapy was 33 months and was 21 months for previously treated patients. Survival after progression of disease was also strongly correlated with the degree of prior therapy. No successful salvage regimen after initial fludarabine therapy was shown for patients refractory to alkylating agents, although fludarabine achieved further remissions in patients who had received fludarabine as their initial treatment or were not refractory to alkylating agents. The morbidity of patients in unmaintained remission on discontinuation of fludarabine was low, with less than one episode of infection per patient-year at risk. The morbidity during this time was correlated with clinical response and whether the patients had received prior therapy. Although fludarabine is a very effective cytoreductive regimen, most patients, including those who achieved true complete remissions, will have recurrent disease. Longer follow-up and comparative trials are required before the effect of fludarabine on survival is shown.

scholarly journals Results of fludarabine and prednisone therapy in 264 patients with chronic lymphocytic leukemia with multivariate analysis-derived prognostic model for response to treatment [see comments]

Blood ◽  
1993 ◽  
Vol 82 (6) ◽  
pp. 1695-1700 ◽  
Author(s):  
S O'Brien ◽  
H Kantarjian ◽  
M Beran ◽  
T Smith ◽  
C Koller ◽  
...  
Keyword(s):  
Chronic Lymphocytic Leukemia ◽  
Median Time ◽  
Alkylating Agents ◽  
Pneumocystis Carinii ◽  
Lymphocytic Leukemia ◽  
Response To Treatment ◽  
Time To Progression ◽  
Prior Therapy ◽  
Previously Treated Patients ◽  
Previously Treated

Abstract Two hundred sixty-four patients with chronic lymphocytic leukemia were treated with fludarabine 30 mg/m2 intravenously for 30 minutes each day for 5 days and with prednisone 30 mg/m2 orally each day for 5 days. Courses were repeated monthly. Of the 264 patients. 125 patients (47%) had Rai stage III-IV disease; 169 patients (64%) were previously treated with a median of 3 prior regimens; and 138 of them (82%) were refractory to therapy with alkylating agents. The overall response (OR) and complete response (CR) rates in the 169 previously-treated patients were 52% and 37%; these were 74% and 63%, respectively, in Rai stage O- II patients and declined to 64% and 46%, respectively, in Rai III-IV disease. Among the previously untreated patients, the OR and CR rates were 79% and 63%, these being 85% and 70%, respectively, in Rai O-II patients, and declining to 64% and 46%, respectively, in Rai III-IV disease. The incidence of minor infections or fever of unknown origin was similar in all patient groups and occurred in 22% of courses. The incidence of sepsis and/or pneumonia was significantly correlated with the extent of prior therapy and with Rai stage, and ranged from 3% of courses in the previously untreated Rai O-II patients, to 13% of courses in the previously treated Rai III-IV patients. Listeria sepsis or Pneumocystis carinii pneumonia was noted in 14 patients. With therapy, CD4 levels were uniformly depressed from a median 1,015/microL pretreatment to a median 159/microL after 3 months of fludarabine therapy. Median time to progression in previously treated patients was 22 months. In previously untreated patients, median time to progression was 30 months for patients who achieved a partial remission and has not been reached in patients who achieved a CR with a median follow-up of 2 years. The median survival was 18 months for previously treated patients and has not been reached for previously untreated patients. Response rates in previously treated and untreated patients, as well as infection rates, were identical to those seen in 110 patients treated with the same dose schedule of fludarabine alone. Logistic regression analysis selected 4 factors to be significantly associated with worse response: Rai III-IV stage disease, prior therapy, older age, and low albumin levels. The regression equation was used to derive a probability of response based on the 4 characteristics. When the model was applied to the same population, patients could be divided into 4 prognostic groups with different outcomes.

scholarly journals Long-term follow-up of patients with chronic lymphocytic leukemia treated with fludarabine as a single agent

Blood ◽  
1993 ◽  
Vol 81 (11) ◽  
pp. 2878-2884 ◽  
Author(s):  
MJ Keating ◽  
S O'Brien ◽  
H Kantarjian ◽  
W Plunkett ◽  
E Estey ◽  
...  
Keyword(s):  
Chronic Lymphocytic Leukemia ◽  
Clinical Response ◽  
Alkylating Agents ◽  
Single Agent ◽  
Response To Therapy ◽  
Lymphocytic Leukemia ◽  
Strongly Correlated ◽  
Prior Therapy ◽  
Previously Treated

The clinical response and survival of 113 patients with at least 3-year follow-up after treatment with fludarabine as a single agent for chronic lymphocytic leukemia has been evaluated. Seventy-eight patients were previously treated and 35 were untreated. The response to therapy and survival were strongly correlated with the degree of previous therapy, the stage of disease, and whether or not the patients were refractory to alkylating agents. Other characteristics associated with survival were the age of the patient and the serum albumin level at the start of therapy. The median time to progression of responders who had not received prior therapy was 33 months and was 21 months for previously treated patients. Survival after progression of disease was also strongly correlated with the degree of prior therapy. No successful salvage regimen after initial fludarabine therapy was shown for patients refractory to alkylating agents, although fludarabine achieved further remissions in patients who had received fludarabine as their initial treatment or were not refractory to alkylating agents. The morbidity of patients in unmaintained remission on discontinuation of fludarabine was low, with less than one episode of infection per patient-year at risk. The morbidity during this time was correlated with clinical response and whether the patients had received prior therapy. Although fludarabine is a very effective cytoreductive regimen, most patients, including those who achieved true complete remissions, will have recurrent disease. Longer follow-up and comparative trials are required before the effect of fludarabine on survival is shown.

Daunomycin Treatment in Chronic Lymphoproliferative Disorders

1968 ◽  
Vol 54 (6) ◽  
pp. 465-481 ◽  
Author(s):  
Gianni Bonadonna ◽  
Silvio Monfardini ◽  
Antonio Guindani
Keyword(s):  
Chronic Lymphocytic Leukemia ◽  
Alkylating Agents ◽  
Stage Iv ◽  
Lymphoproliferative Disorders ◽  
Lymphocytic Leukemia ◽  
Cutaneous Lesions ◽  
Previously Treated ◽  
Significant Regression ◽  
Different Doses

Daunomycin was administered to 16 patients with chronic lymphoproliferative disorders (10 with Stage IV lymphoreticular sarcomas and 6 with chronic lymphocytic leukemia). The age of subjects was ranging between 36 and 64 years (average 54 years). 8 out of 16 patients had been previously treated with radiotherapy and/or chemotherapy. The drug was injected intravenously at the initial dose of 0.6 mg/kg (7 cases), 0.8 mg/kg (8 cases) and 1 mg/kg (1 case) for 3–4 consecutive days. After 1 day interval, treatment was continued in most cases on alternate days schedule until signs of toxicity appeared. In some patients after the initial course the dose/kg was increased or decreased according to the peripheral blood picture. The total dose ranged between 2.2 to 13.3 mg/kg. In 7 patients prednisone (50 mg daily by mouth) was given in association to daunomycin (tables 1 and 2). Objective responses were seen in 5 out of 6 patients with chronic lymphocytic leukemia. While a consistent shrinkage of the nodes and especially of the spleen was observed in all responsive cases, the fall in the leukocyte level was mild and transient. In lymphoreticular sarcomas 5 out of 10 patients responded; the most significant regression was obtained in patients with splenomegaly, but also lymphonodes, hepatomegaly, pulmonary and cutaneous lesions responded. Two patients had also the bone marrow infiltrated with extrinsic cells: no significant changes were seen after treatment with 6 and 6.2 mg/kg. Regression usually occurred after few doses; nevertheless in all but one responsive patients they were incomplete. Maintenance treatment was then started with alkylating agents. The patients treated with daunomycin and prednisone did not show any better response than those treated with daunomycin alone. In 5 cases a sudden dyspnea, tachycardia and hypotension developed after different doses of daunomycin ranging from 2.2 to 8 mg/kg. Four patients died within 24 hours and one after 5 days from the beginning of symptoms. EKG abnormalities (tachicardia, flattening of ST and T waves) were recorded in all patients died with cardiac failure. In two cases the EKG changes appeared only after daunomycin administration while in three cases mild electric abnormalities present before the treatment got worse after few doses of daunomycin. Necroscopy was performed only in one case where besides superficial necrosis of the intestinal mucosa no specific alterations of the heart and vessels were seen. The conclusion is that daunomycin can produce rapid objective responses in chronic lymphoproliferative disorders, although the quality of these regressions in the majority of patients is insufficient to influence the natural course of the disease. Prolongued administration of the drug especially in patients previously treated with chemotherapy is not recommended because of the severe marrow depression. The so-called cardiac toxicity seems from this study to be dose-indipendent in patients with cardiovascular disease and EKG abnormalities before drug administration. Daunomycin therefore should not be given even in small dosage to patients with EKG abnormalities.

scholarly journals Results of fludarabine and prednisone therapy in 264 patients with chronic lymphocytic leukemia with multivariate analysis-derived prognostic model for response to treatment [see comments]

Blood ◽  
1993 ◽  
Vol 82 (6) ◽  
pp. 1695-1700 ◽  
Author(s):  
S O'Brien ◽  
H Kantarjian ◽  
M Beran ◽  
T Smith ◽  
C Koller ◽  
...  
Keyword(s):  
Chronic Lymphocytic Leukemia ◽  
Median Time ◽  
Alkylating Agents ◽  
Pneumocystis Carinii ◽  
Lymphocytic Leukemia ◽  
Response To Treatment ◽  
Time To Progression ◽  
Prior Therapy ◽  
Previously Treated Patients ◽  
Previously Treated

Two hundred sixty-four patients with chronic lymphocytic leukemia were treated with fludarabine 30 mg/m2 intravenously for 30 minutes each day for 5 days and with prednisone 30 mg/m2 orally each day for 5 days. Courses were repeated monthly. Of the 264 patients. 125 patients (47%) had Rai stage III-IV disease; 169 patients (64%) were previously treated with a median of 3 prior regimens; and 138 of them (82%) were refractory to therapy with alkylating agents. The overall response (OR) and complete response (CR) rates in the 169 previously-treated patients were 52% and 37%; these were 74% and 63%, respectively, in Rai stage O- II patients and declined to 64% and 46%, respectively, in Rai III-IV disease. Among the previously untreated patients, the OR and CR rates were 79% and 63%, these being 85% and 70%, respectively, in Rai O-II patients, and declining to 64% and 46%, respectively, in Rai III-IV disease. The incidence of minor infections or fever of unknown origin was similar in all patient groups and occurred in 22% of courses. The incidence of sepsis and/or pneumonia was significantly correlated with the extent of prior therapy and with Rai stage, and ranged from 3% of courses in the previously untreated Rai O-II patients, to 13% of courses in the previously treated Rai III-IV patients. Listeria sepsis or Pneumocystis carinii pneumonia was noted in 14 patients. With therapy, CD4 levels were uniformly depressed from a median 1,015/microL pretreatment to a median 159/microL after 3 months of fludarabine therapy. Median time to progression in previously treated patients was 22 months. In previously untreated patients, median time to progression was 30 months for patients who achieved a partial remission and has not been reached in patients who achieved a CR with a median follow-up of 2 years. The median survival was 18 months for previously treated patients and has not been reached for previously untreated patients. Response rates in previously treated and untreated patients, as well as infection rates, were identical to those seen in 110 patients treated with the same dose schedule of fludarabine alone. Logistic regression analysis selected 4 factors to be significantly associated with worse response: Rai III-IV stage disease, prior therapy, older age, and low albumin levels. The regression equation was used to derive a probability of response based on the 4 characteristics. When the model was applied to the same population, patients could be divided into 4 prognostic groups with different outcomes.

Ad-ISF35- Transduced Autologous Cells Promote In Vitro and In Vivo Chemosensitization to FCR and Durable Complete Responses In Patients with Del(17p)/P53 Defective Chronic Lymphocytic Leukemia.

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 1472-1472
Author(s):  
Januario E Castro ◽  
Johanna Melo-Cardenas ◽  
Juan Sebastian Barajas-Gamboa ◽  
Mauricio Urquiza ◽  
Mark J. Cantwell ◽  
...  
Keyword(s):  
Chronic Lymphocytic Leukemia ◽  
Ex Vivo ◽  
Adenovirus Vector ◽  
Chemotherapeutic Agents ◽  
Lymphocytic Leukemia ◽  
Cytotoxic Agents ◽  
Multiparameter Flow Cytometry ◽  
Cytokine Analysis ◽  
Apoptotic Factors

Abstract Abstract 1472 Background: Chronic lymphocytic leukemia (CLL) cells with del(17p) typically have loss of functional P53, rendering them refractory to chemotherapeutic agents. However, del(17p) CLL cells activated by CD40L (CD154) are induced to express pro-apoptotic factors that re-sensitize cells to the cytotoxic activity of P53-dependent drugs, such as fludarabine (F-ara-A). Chemotherapy re-sensitization is mediated in part by induction of p73, a p53-related transcription factor. To examine whether a CD154-based therapeutic strategy can be developed in vivo for del(17p) and/or fludarabine refractory CLL, a phase 1b clinical study evaluating an autologous cellular gene immunotherapy is being conducted. Autologous CLL cells transduced ex vivo with a replication defective adenovirus vector encoding a membrane-stable, re-engineered form of CD154 (Ad-ISF35) are administered, followed by standard courses of FCR in subjects with high-risk fludarabine refractory and/or del(17p) CLL. Methods: Subjects with fludarabine refractory and/or del(17p) receive three IV doses (one dose every two weeks) of 3×108 autologous CLL cells that have been transduced ex vivo with Ad-ISF35. Two weeks following the third dose of Ad-ISF35-transduced cells, subjects receive standard monthly cycles of fludarabine, cyclophosphamide and rituximab (FCR). Study endpoints include analysis of safety and efficacy. Correlative analyses are conducted for evidence of drug re-sensitization, regulation of apoptotic pathways, cytokine analysis, and humoral immune responses to the adenovirus vector and ISF35 transgene. Results: To date, four patients have completed treatment. Two patients have achieved a compete response, one of them without detectable minimal residual disease (MRD) by sensitive multiparameter flow cytometry of marrow mononuclear cells after completion of treatment. These responses have been durable after a median follow up of 18 months. One patient achieved a partial response with complete resolution of lymphocytosis, lymphadenopathy and splenomegaly, but residual CLL in the bone marrow. The remaining patient had progressive disease despite an initial response to both infusion of Ad-ISF35-transduced cells and FCR chemoimmunotherapy. Infusion of Ad-ISF35 transduced cells has been well tolerated. Overall, the most common adverse events have been transient fever, malaise and fatigue associated with infusion of Ad-ISF35-transduced cells and cytopenias after treatment with FCR. Prior to ISF35 treatment, CLL cells from patients were resistant to F-ara-A induced apoptosis (IC50 > 10μM). However, one day following the first infusion of Ad-ISF35-transduced CLL cells, patient cells became sensitive to F-ara-A (IC50 0.3–1 μM). In addition, pro-apoptotic factors, including Bid, DR5, CD95, and P73 were induced in the non-transduced “bystander” CLL population following ISF35 infusion. These pro-apoptotic effects persisted ≥ 2 weeks following IV infusion. The sera from treated patients showed increase in IL-6 and IFN-γ after infusion of Ad-ISF35 transduced CLL cells. Despite evidence of anti-adenovirus antibody responses in the treated patients, there was no detectable anti-human CD154 production before or after ISF35 treatment. Conclusions: The results indicate that Ad-ISF35-cell-gene therapy can sensitize P53-deficient CLL to “P53-dependent” cytotoxic agents in vivo, allowing for effective and durable clinical responses. These data are very encouraging and suggest that this unique chemoimmunotherapy re-sensitization strategy could offer a valuable treatment option for patients who otherwise would be resistant to standard forms of therapy. Disclosures: Cantwell: Memgen: Employment. Kipps:Memgen, LLC: Membership on an entity's Board of Directors or advisory committees.

scholarly journals Idelalisib for the Treatment of Chronic Lymphocytic Leukemia

ISRN Oncology ◽  
2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Maliha Khan ◽  
Areeba Saif ◽  
Steven Sandler ◽  
Aibek E. Mirrakhimov
Keyword(s):  
Chronic Lymphocytic Leukemia ◽  
Kinase Inhibitor ◽  
Alkylating Agents ◽  
Treatment Strategies ◽  
The United States ◽  
Lymphocytic Leukemia ◽  
Durable Response ◽  
Significant Toxicity ◽  
Treatment Naïve ◽  
Chemotherapeutic Treatment

Chronic lymphocytic leukemia is the most common leukemia in the United States. It is a slowly progressive disease, with an 82% five-year survival rate. The treatment strategies are highly individualized with patients in the early and stable stages typically not requiring treatment. However, those with progressive or clinically advanced disease will require treatment. Cytotoxic drugs, such as the alkylating agents, purine nucleoside antagonists, and immunotherapeutic agents, have been the mainstay of chemotherapeutic treatment in CLL. However, given the lack of therapeutic specificity, these medications (especially older ones) have limited tolerability due to side effects. In this paper, we will discuss the data on the use of phosphatidylinositol 3 kinase inhibitor Idelalisib in the management of patients with chronic lymphocytic leukemia. The preclinical and clinical data thus far demonstrate that Idelalisib produces a dramatic and durable response in patients with chronic lymphocytic leukemia and without causing significant toxicity. Moving forward, the ongoing clinical trials will help address the various questions currently being raised regarding the long-term application and safety of Idelalisib. With greater clinical experience following more widespread use of Idelalisib, we will be able to determine the optimal combination therapies in treatment-naïve and relapsed/refractory patients, resulting in more individualized therapeutic strategies for patients with chronic lymphocytic leukemia.

scholarly journals Targeting CD38 is lethal to Breg-like chronic lymphocytic leukemia cells and Tregs, but restores CD8+ T-cell responses

2020 ◽  
Vol 4 (10) ◽  
pp. 2143-2157 ◽  
Author(s):  
Alak Manna ◽  
Timothy Kellett ◽  
Sonikpreet Aulakh ◽  
Laura J. Lewis-Tuffin ◽  
Navnita Dutta ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Chronic Lymphocytic Leukemia ◽  
Cd8 T Cells ◽  
Mononuclear Cells ◽  
Transforming Growth Factor ◽  
Ex Vivo ◽  
Xenograft Model ◽  
Lymphocytic Leukemia ◽  
Dependent Manner

Abstract Patients with chronic lymphocytic leukemia (CLL) are characterized by monoclonal expansion of CD5+CD23+CD27+CD19+κ/λ+ B lymphocytes and are clinically noted to have profound immune suppression. In these patients, it has been recently shown that a subset of B cells possesses regulatory functions and secretes high levels of interleukin 10 (IL-10). Our investigation identified that CLL cells with a CD19+CD24+CD38hi immunophenotype (B regulatory cell [Breg]–like CLL cells) produce high amounts of IL-10 and transforming growth factor β (TGF-β) and are capable of transforming naive T helper cells into CD4+CD25+FoxP3+ T regulatory cells (Tregs) in an IL-10/TGF-β-dependent manner. A strong correlation between the percentage of CD38+ CLL cells and Tregs was observed. CD38hi Tregs comprised more than 50% of Tregs in peripheral blood mononuclear cells (PBMCs) in patients with CLL. Anti-CD38 targeting agents resulted in lethality of both Breg-like CLL and Treg cells via apoptosis. Ex vivo, use of anti-CD38 monoclonal antibody (mAb) therapy was associated with a reduction in IL-10 and CLL patient-derived Tregs, but an increase in interferon-γ and proliferation of cytotoxic CD8+ T cells with an activated phenotype, which showed an improved ability to lyse patient-autologous CLL cells. Finally, effects of anti-CD38 mAb therapy were validated in a CLL–patient-derived xenograft model in vivo, which showed decreased percentage of Bregs, Tregs, and PD1+CD38hiCD8+ T cells, but increased Th17 and CD8+ T cells (vs vehicle). Altogether, our results demonstrate that targeting CD38 in CLL can modulate the tumor microenvironment; skewing T-cell populations from an immunosuppressive to immune-reactive milieu, thus promoting immune reconstitution for enhanced anti-CLL response.

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