Activated innate lymphoid cells are associated with a reduced susceptibility to graft-versus-host disease.

Allogeneic hematopoietic stem cell transplantation (HSCT) is widely used to treat hematopoietic cell disorders but is often complicated by graft-versus-host disease (GVHD), which causes severe epithelial damage. Here we have investigated longitudinally the effects of induction chemotherapy, conditioning radiochemotherapy, and allogeneic HSCT on composition, phenotype, and recovery of circulating innate lymphoid cells (ILCs) in 51 acute leukemia patients. We found that reconstitution of ILC1, ILC2, and NCR(-)ILC3 was slow compared with that of neutrophils and monocytes. NCR(+) ILC3 cells, which are not present in the circulation of healthy persons, appeared both after induction chemotherapy and after allogeneic HSCT. Circulating patient ILCs before transplantation, as well as donor ILCs after transplantation, expressed activation (CD69), proliferation (Ki-67), and tissue homing markers for gut (α4ß7, CCR6) and skin (CCR10 and CLA). The proportion of ILCs expressing these markers was associated with a decreased susceptibility to therapy-induced mucositis and acute GVHD. Taken together, these data suggest that ILC recovery and treatment-related tissue damage are interrelated and affect the development of GVHD.

Evaluation of Dutch guideline for just-in-time addition of plerixafor to stem cell mobilization in patients who fail with granulocyte-colony-stimulating factor.

BACKGROUND: Plerixafor in combination with granulocyte-colony-stimulating factor (G-CSF) is approved for the use of stem cell collection in patients who fail to mobilize on G-CSF. In 2009 the Stem Cell Working Party of the Dutch-Belgian Cooperative Trial group for Hematology Oncology (HOVON) composed a guideline for the use of plerixafor. According to this guideline it is recommended to add plerixafor to G-CSF in patients with circulating CD34+ cell counts of fewer than 20 × 10(6) /L on 2 consecutive days accompanied by increasing white blood cells. STUDY DESIGN AND METHODS: In this analysis we evaluated retrospectively the outcome of the use of this guideline in the Netherlands. In total 111 patients received plerixafor with a median one administration (range, one to four administrations). Of these patients 55.8% had non-Hodgkin lymphoma, 31.5% multiple myeloma, 8.1% Hodgkin lymphoma, and 4.5% nonhematologic malignancies. RESULTS: In 63.9% patients sufficient numbers of CD34+ cells were collected. In patients with multiple myeloma more successful mobilizations with plerixafor were observed compared to patients with non-Hodgkin lymphoma (71.4% vs. 61.3%). In patients with circulating CD34+ cell counts of at least 2.0 × 10(6) /L before administration of plerixafor a successful mobilization was achieved in 76.5%, and in the patients with very low (0-1 × 10(6) /L) circulating CD34+ cell counts the success rate was 44.2%. CONCLUSION: Application of the HOVON guideline on the just-in-time administration of plerixafor is effective for mobilization of hematopoietic stem cells in the majority of patients. Stem cell yield in patients with non-Hodgkin lymphoma was lower compared to patients with multiple myeloma. Also patients with very low circulating CD34+ cells before addition of plerixafor might benefit from this approach.

Rapid induction of single donor chimerism after double umbilical cord blood transplantation preceded by reduced intensity conditioning: results of the HOVON 106 phase II study.

Double umbilical cord blood transplantation is increasingly applied in the treatment of adult patients with high-risk hematological malignancies and has been associated with improved engraftment as compared to that provided by single unit cord blood transplantation. The mechanism of improved engraftment is, however, still incompletely understood as only one unit survives. In this multicenter phase II study we evaluated engraftment, early chimerism, recovery of different cell lineages and transplant outcome in 53 patients who underwent double cord blood transplantation preceded by a reduced intensity conditioning regimen. Primary graft failure occurred in one patient. Engraftment was observed in 92% of patients with a median time to neutrophil recovery of 36 days (range, 15-102). Ultimate single donor chimerism was established in 94% of patients. Unit predominance occurred by day 11 after transplantation and early CD4(+) T-cell chimerism predicted for unit survival. Total nucleated cell viability was also associated with unit survival. With a median follow up of 35 months (range, 10-51), the cumulative incidence of relapse and non-relapse mortality rate at 2 years were 39% and 19%, respectively. Progressionfree survival and overall survival rates at 2 years were 42% (95% confidence interval, 28-56) and 57% (95% confidence interval, 43-70), respectively. Double umbilical cord blood transplantation preceded by a reduced intensity conditioning regimen using cyclophosphamide/fludarabine/4 Gy total body irradiation results in a high engraftment rate with low non-relapse mortality. Moreover, prediction of unit survival by early CD4(+) lymphocyte chimerism might suggest a role for CD4(+) lymphocyte mediated unit-versus-unit alloreactivity. www.trialregister.nl NTR1573.

Lenalidomide maintenance after nonmyeloablative allogeneic stem cell transplantation in multiple myeloma is not feasible: results of the HOVON 76 Trial.

To improve the outcome of allogeneic stem cell transplantation (allo-SCT) in multiple myeloma as part of first-line treatment, we prospectively investigated the feasibility and efficacy of lenalidomide maintenance. Patients started maintenance 1 to 6 months after nonmyeloablative allo-SCT. Lenalidomide was dosed 10 mg on days 1 to 21 of a 28-day schedule for a total of 24 cycles. Peripheral blood samples were taken to evaluate immune modulating effects. Thirty-five eligible patients were enrolled, and 30 started with lenalidomide. After 2 cycles, 14 patients (47%) had to stop treatment, mainly because of the development of acute graft versus host disease (GVHD). In total, 13 patients (43%) stopped treatment because of development of GVHD, 5 patients (17%) because of other adverse events, and 5 patients (17%) because of progression. Responses improved in 37% of patients, and the estimated 1-year progression-free survival from start of maintenance was 69% (90% confidence interval, 53%-81%). Lenalidomide increased the frequency of human leukocyte antigen-DR(+) T cells and regulatory T cells, without correlation with clinical parameters. In conclusion, lenalidomide maintenance 10 mg daily after nonmyeloablative allo-SCT with unmanipulated graft in multiple myeloma patients is not feasible, mainly because of the induction of acute GVHD. This trial was registered at www.trialregister.nl as #NTR1645.

Posaconazole treatment in hematology patients: a pilot study of therapeutic drug monitoring.

BACKGROUND: Posaconazole is indicated for prophylaxis and salvage therapy of invasive fungal infections. Based on pharmacokinetic-pharmacodynamic data, minimum serum concentrations for each indication have been proposed, for example, for prophylaxis >0.5-0.7 mg/L and for primary therapy >1.0 mg/L. Several drugs and comorbidities have been identified to hinder reaching target concentrations. It is postulated that patients with interacting drugs or comorbidities should be monitored for posaconazole concentrations. PATIENTS AND METHODS: Patients aged 18 years and above were included for retrospective analysis if at least 1 serum posaconazole concentration was measured in our hospital between June 2009 and May 2010. Serum posaconazole concentrations were measured using a validated liquid chromatographic method with tandem mass-spectrometric analytical method. Patient characteristics, underlying disease, comedication, comorbidities, and therapeutic drug monitoring (TDM) interventions were collected retrospectively, based on (electronic) medical records. RESULTS: Seventeen patients were included, from whom 42 samples for posaconazole measurement were collected. In total, 8 patients did not reach adequate posaconazole concentration. Sixty percent of patients using a proton pump inhibitor (PPI) did not reach target concentration with a corresponding median concentration of 0.48 mg/L. PPI usage was shown to significantly increase the risk of attaining below-target serum posaconazole concentration (P = 0.04 for all measurements). Graft-versus-host disease and diarrhea were associated with significant below-target concentrations (P = 0.03 and P < 0.001, respectively, for all measurements). One patient developed a breakthrough pulmonary aspergillosis at low posaconazole concentration (0.37 mg/L). Two patients had high concentrations (>3 mg/L), without adverse events. After TDM intervention, 3 out of 4 patients (75%) reached target concentration by spreading the administration of the dose. CONCLUSIONS: Below-target posaconazole concentrations were significantly more frequent in PPI users, graft-versus-host disease, and diarrhea. TDM seemed to be a helpful tool to identify low concentrations and to optimize posaconazole treatment.

NOD2/CARD15 variants are not a risk factor for clinical outcome after nonmyeloablative allogeneic stem cell transplantation.

Single nucleotide polymorphisms (SNPs) in the innate immunity receptor NOD2/CARD15 have been demonstrated to modulate the outcome of allogeneic hematopoietic stem cell transplantation (SCT). The effect of NOD2/CARD15 polymorphism is reported to be associated with type of donor (sibling or matched unrelated donor) as well as type of conditioning regimen. We reviewed NOD2/CARD15 SNPs in all donor/recipient pairs of 192 consecutive patients who received nonmyeloablative allogeneic SCT at our institution between 2002 and 2006. All patients were treated with fludarabine 30 mg/m(2)/day for 3 days followed by 200 cGy total-body irradiation (TBI) (n = 154) or TBI alone (n = 38) and received grafts from HLA-matched related (n = 132) or unrelated (n = 61) donors. NOD2/CARD15 polymorphisms were observed in 36 of 192 (19%) patients and in 35 of 192 (18%) donors. The incidences of acute and chronic graft-versus-host disease (aGVHD, cGVHD) were 39% and 49%, respectively, in patients with NOD2/CARD15 variants versus 51% and 61% in patients with wild type. The relapse rate at 3 years was 38% in patients with variants and 36% in patients with wild type. The incidence of transplant-related mortality was 22% for patients with variants and 21% for patients with wild type. Overall survival (OS) at 3 years was 56% in patients with variants and 64% in patients with wild-type NOD2/CARD15. There was no significant impact of NOD2/CARD15 mutations on clinical outcome (all P > .05, Kaplan-Meier and Fine and Gray's tests). These data indicate that mutations in the NOD2/CARD15 gene are not a risk factor for clinical outcome in nonmyeloablative allogeneic SCT. Therefore, screening for NOD2/CARD15 polymorphisms in patients or donors does not have additional value in patients undergoing nonmyeloablative SCT.

Hematopoietic stem cell transplantation after reduced intensity conditioning in acute myelogenous leukemia patients older than 40 years.

Reduced intensity conditioning (RIC) protocols are increasingly used for allogeneic hematopoietic stem cell transplantation (HSCT) in elderly patients. We analyzed the outcome of RIC HSCT in acute myelogenous leukemia (AML) patients over the age of 40 years. Forty-three AML or high-risk myelodysplastic syndrome (MDS) patients were treated with a fludarabine and low-dose total-body irradiation (TBI)-based pretransplantation regimen. Donors were HLA-compatible sibling (68%) or unrelated volunteers (34%). All but 2 AML patients were in complete remission (CR) at the time of transplantation. Seventy-six percent of patients had a poor risk profile. Hematologic recovery was fast, and primary graft failure occurred in 1 patient. Two patients with active disease at the time of HSCT experienced ongoing relapse. Infections were diagnosed in 9 patients (21%), and 6 patients (14%) were treated for cytomegalovirus (CMV) reactivation. Sixty percent of patients developed acute graft-versus-host disease (aGVHD), which was grade II in 40% and grade III in 12%. The cumulative incidence of chronic graft-versus-host disease (cGVHD) was 33% at 1 and at 2 years. Treatment-related mortality (TRM) was low (9%), total nonrelapse mortality (NRM) was 19%. After a median follow-up of 571 days, 16 patients (37%) experienced relapse. Median disease-free and overall survival (DFS; OS) were 24 and 31 months, respectively. There were no differences in complications and outcome between recipients of sibling and unrelated grafts. In conclusion, fludarabine plus low-dose TBI-based RIC HSCT is effective in AML patients over the age of 40 years without active disease at the time of transplant and is associated with low TRM.

Cathepsin B mediates caspase-independent cell death induced by microtubule stabilizing agents in non-small cell lung cancer cells.

We have previously reported that the microtubule stabilizing agents (MSAs) paclitaxel, epothilone B and discodermolide induce caspase-independent cell death in non-small cell lung cancer (NSCLC) cells. Here we present two lines of evidence indicating a central role for the lysosomal protease cathepsin B in mediating cell death. First, inhibition of cathepsin B, and not of caspases or other proteases, such as cathepsin D or calpains, results in a strong protection against drug-induced cell death in several NSCLC cells. Second, MSAs trigger disruption of lysosomes and release and activation of cathepsin B. Interestingly, inhibition of cathepsin B prevents the appearance of multinucleated cells, an early characteristic of MSA-induced cell death, pointing to a central, proximal role for cathepsin B in this novel cell death pathway.

Late activation of apoptotic pathways plays a negligible role in mediating the cytotoxic effects of discodermolide and epothilone B in non-small cell lung cancer cells.

Discodermolide and epothilone B are promising novel chemotherapeutic agentsthat induce cell death through potent stabilization of microtubules. In this study, we investigated the cellular and molecular events underlying the cytotoxicity of these drugs in non-small cell lung carcinoma (NSCLC) cell lines, focusing on apoptotic characteristics. IC80 concentrations of either drug effectively disrupted the microtubule cytoskeleton of H460 cells and induced cell cycle disturbances with early accumulation in the G2-M phase and development of a hypodiploid cell population in both H460 and SW1573 cells. These events were followed by abnormal chromosome segregation during mitosis and subsequent appearance of multinucleated cells. At later time points, the cells displayed several apoptotic features, such as nuclear condensation and fragmentation as well as Annexin V staining, cleavage of poly(ADP-ribose) polymerase and the activation of caspases. To examine the contribution of apoptotic pathways to the cytotoxic effects of these agents, the involvement of the mitochondria and death receptor routes was studied. At 48 h after treatment, both agents disrupted mitochondria of H460 cells, as indicated by cytochrome c release. Nonetheless, H460 cells stably overexpressing antiapoptotic Bcl-2 or Bcl-xL did not show any protective effect from cell death induced by either drug. Possible death receptor dependency was investigated in H460 cells stably overexpressing dominant-negative FADD, which failed to reduce the cytotoxic effects of discodermolide and epothilone B. To study the role of caspases more directly, the effect of stable overexpression of the caspase-8 inhibitor cytokine response modifier A was studied in H460 cells. Furthermore, the effect of the pancaspase inhibitor z-Val-Ala-Asp-fluoromethyl ketone was investigated in a panel of lung carcinoma cell lines. Interestingly, caspase inhibition did not rescue cells from discodermolide or epothilone B-induced cell death. In conclusion, these results demonstrate that despite several apoptotic features detected at relatively late time points after drug exposure, apoptosis is not the dominant mode of cell death and induced low but efficacious concentrations of discodermolide and epothilone B.

Paclitaxel triggers cell death primarily via caspase-independent routes in the non-small cell lung cancer cell line NCI-H460.

PURPOSE: Here we report on the role of mitochondria, death receptors (DRs), and caspases in exerting the cytotoxic effect of clinically relevant concentrations of paclitaxel in the non-small cell lung cancer cell line NCI-H460. EXPERIMENTAL DESIGN: We have characterized paclitaxel-induced cell death with annexin V, propidium iodide staining, and poly(ADP-ribose) polymerase cleavage assays. The involvement of the mitochondria pathway was studied by monitoring cytochrome c release and using H460 cells stable in overexpressing Bcl-2 or Bcl-x(L). DR dependency was analyzed in FADD dominant-negative or cytokine response modifier A-overexpressing cells, and a possible role for DR4 and DR5 was investigated by antagonistic antibodies. Caspase activity and cleavage assays and treatment with the synthetic inhibitor zVAD-fmk were used to determine the involvement of caspases. RESULTS: Paclitaxel-treated cells displayed several features of apoptosis, including annexin V staining and poly(ADP-ribose) polymerase cleavage. The sequence of events suggested the involvement of a DR, as indicated by an early role for Fas-associated death domain and caspase-8, followed by cleavage of Bid and the disruption of mitochondria; nonetheless, we failed to demonstrate the involvement of DR4 and DR5. Interestingly, inhibition of either one of these routes only resulted in a 30% reduction of cell death that was in line with the observed small effect of caspase inhibition by zVAD-fmk on H460 cell survival. CONCLUSION: Paclitaxel triggers cell death in H460 cells mainly via a currently unidentified caspase-independent mechanism in which the basic apoptotic machinery is merely coactivated. This finding is in sharp contrast with the largely caspase-dependent response elicited by DNA-damaging agents in these cells. We speculate on therapeutic implications.

Novel approaches to the treatment of non-small cell lung cancer.

Prognosis of non-small cell lung carcinomas (NSCLC) remains poor, especially in advanced disease. The introduction of new cytotoxic agents in the past decade did only attain minor improvements in survival. It is rather clear that chemotherapy may have reached a plateau, and that it will be difficult to obtain better results in advanced NSCLC by chemotherapy alone. Novel treatment modalities are urgently needed in advanced NSCLC. Backed-up by advances in the understanding of tumor cell biology, a new generation of anticancer agents specifically directed at targets such as tyrosine kinases, farnesyl transferase, angiogenesis factors, matrixmetalloproteinases and oncogenes has been developed in recent years. In this review, we give a brief summary of the state-of-the-art treatment of NSCLC, highlighting its limitations. Novel systemic approaches are then discussed in detail with focus on their mechanistic rationale, stage of clinical development and possible drawbacks. Finally, perspectives of future applications and impact on the treatment of NSCLC are also discussed.