Bortezomib before and after high-dose therapy in myeloma: long-term results from the phase III HOVON-65/GMMG-HD4 trial.

The Dutch-Belgian Cooperative Trial Group for Hematology Oncology Group-65/German-speaking Myeloma Multicenter Group-HD4 (HOVON-65/GMMG-HD4) phase III trial compared bortezomib (BTZ) before and after high-dose melphalan and autologous stem cell transplantation (HDM, PAD arm) compared with classical cytotoxic agents prior and thalidomide after HDM (VAD arm) in multiple myeloma (MM) patients aged 18-65 years. Here, the long-term follow-up and data on second primary malignancies (SPM) are presented. After a median follow-up of 96 months, progression-free survival (censored at allogeneic transplantation, PFS) remained significantly prolonged in the PAD versus VAD arm (hazard ratio (HR)=0.76, 95% confidence interval (95% CI) of 0.65-0.89, P=0.001). Overall survival (OS) was similar in the PAD versus VAD arm (HR=0.89, 95% CI: 0.74-1.08, P=0.24). The incidence of SPM were similar between the two arms (7% each, P=0.73). The negative prognostic effects of the cytogenetic aberration deletion 17p13 (clone size ⩾10%) and renal impairment at baseline (serum creatinine >2 mg dl-1) on PFS and OS remained abrogated in the PAD but not VAD arm. OS from first relapse/progression was similar between the study arms (HR=1.02, P=0.85). In conclusion, the survival benefit with BTZ induction/maintenance compared with classical cytotoxic agents and thalidomide maintenance is maintained without an increased risk of SPM.

Clinical and immunological significance of HLA-E in stem cell transplantation and cancer.

Human leukocyte antigen-E (HLA-E) is a nonclassical HLA class I molecule that canonically binds peptides derived from the leader sequence of classical HLA class I. HLA-E can also bind peptides from stress protein [e.g. heat shock protein 60 (Hsp60)] and pathogens, illustrating the importance of HLA-E for anti-viral and anti-tumor immunity. Like classical HLA class I molecules, HLA-E is ubiquitously expressed, however, it is characterized by only a very limited sequence variability and two dominant protein forms have been described (HLA-E*01:01 and HLA-E*01:03). HLA-E influences both the innate and the adaptive arms of the immune system by the engagement of inhibitory (e.g. NKG2A) and activating receptors [e.g. αß T cell receptor (αßTCR) or NKG2C] on NK cells and CD8 T cells. The effects of HLA-E on the cellular immune response are therefore complex and not completely understood yet. Here, we aim to provide an overview of the immunological and clinical relevance of HLA-E and HLA-E polymorphism in stem cell transplantation and in cancer. We review novel insights in the mechanism via which HLA-E expression levels are controlled and how the cellular immune response in transplantation and cancer is influenced by HLA-E.

Increased tumor-specific CD8+ T cell induction by dendritic cells matured with a clinical grade TLR-agonist in combination with IFN-gamma.

The limited response rate of cancer patients treated with dendritic cell (DC)-based vaccines indicates that vast improvements remain necessary. In many murine tumour models it has been demonstrated that the use of innate triggers (e.g. TLR triggers) in the maturation of DC results in higher efficacy. However, as few of these innate triggers are generated clinical grade, there remains a great necessity to fill the gap between fundamental mouse studies and a clinical trial in humans. In the present study we used a TLR2/4-agonist (FMKp which is available clinical grade) in combination with IFN-gamma (FIcocktail) in the maturation of elutriated monocyte-derived DC and compared it with the most used DC in current clinical trials (TNF-alpha/PGE-2, i.e. TP-cocktail). In addition to the assessment of CD4+ T cell polarizing capacity, we compared the quantity and intrinsic quality of induced CD8+ T cells of 2 different DC maturation protocols with all cells from the same donor. Besides differences in the cytokine profile, which could be coupled to increased Th1 and Th17 polarization, we demonstrate in this study that FMKp/IFN-gamma matured DC are twice as effective in inducing cytotoxic T cells against known tumor antigens. Both DCs induced phenotypically equivalent effector memory CD8+ T cells that did not show a significant difference in their intrinsic capacity to kill tumor cells. These findings point to the therapeutic applicability of FI-DC as superior inducers of functional antigen-specific T cells. Their increased chemokine secretion is suggestive of a mechanism by which these DC may compensate for the limited migration observed for all ex vivo cultured DC when applied in patients.

HLA-matched allo-SCT after reduced intensity conditioning with fludarabine/CY in patients with metastatic breast cancer.

Fifteen patients with chemosensitive metastatic breast cancer (MBC) underwent reduced intensity (RIST) allo-SCT between 1999 and 2006. The purpose of this single-center study was to evaluate the feasibility, safety and efficacy of this therapeutic approach. The pretransplant conditioning regimen consisted of fludarabine (25 mg/m(2) at days -5 to -1) and CY (60 mg/kg at days -2, -1). Stem cells were from HLA-matched sibling donors. The treatment-related mortality was 2/15 (13%). Median PFS and OS were 144 days (43-509 days) and 303 days (122-1376 days), respectively. The 1-year PFS was 20%, and the 1-year and 2-year OS was 40 and 20%, respectively. No objective tumor responses were observed, but the relatively long PFS does suggest a graft-vs-tumor effect. Although RIST using this CY/fludarabine regimen is feasible, the efficacy in this set of patients was limited. Future clinical trials should be performed to improve the knowledge of mechanisms of antitumor effects in breast cancer.

Extramedullary relapses after allogeneic non-myeloablative stem cell transplantation in multiple myeloma patients do not negatively affect treatment outcome.

Recent literature suggests that after non-myeloablative allogeneic (NMA) stem cell transplantation (SCT), the incidence of extramedullary (EM) relapse in multiple myeloma (MM) patients is increased and that these relapses have a poor prognosis. However, numbers on incidence and treatment outcome are scarce. We collected data from 54 relapsed MM patients from a total group of 172 treated with sequential autologous and allogeneic NMA SCT at seven transplantation centres. There were 43 (79.6%) systemic relapses, including 6 with concurrent EM localisation. Five patients had a local EM relapse only. Six patients relapsed with only bone involvement. Patients with deletion of chromosome 13 had a higher incidence of EM relapse (30.8 versus 5.6%, P=0.06). EM relapses were treated with donor lymphocyte infusion, radiotherapy, or chemotherapy, especially with novel agents. The response rate was 45.5%, which was not different when compared to patients without EM disease (54.1%). Overall survival and progression-free survival were not significantly different in patients with EM disease, when compared to those without EM disease. In conclusion, the incidence of relapse with EM disease following allogeneic NMA SCT was 20.4%. There was no negative impact of EM relapse on response rate, overall survival and progression-free survival.

Graft-versus-tumor effects on murine mammary carcinoma in a model of nonmyeloablative haploidentical stem cell transplantation.

Despite a slight decrease in mortality over the last decade, breast cancer still remains a leading cause of cancer-related death in women. Although anti-tumor effects have been observed after allogeneic stem cell transplantation (SCT), this treatment is not standard care owing to graft-versus-host disease (GVHD) and scarcity of suitable donors. With the aim of reducing treatment-related mortality and increasing donor availability in clinical situations, we developed a preclinical mouse model that combines nonmyeloablative conditioning with the use of haploidentical donor-recipient pairs. To mimic active disease, CB6F1 mice were inoculated with 5 x 10(4) 4T1 mammary carcinoma cells 10 days before transplantation. Keratinocyte growth factor (KGF) was used as GVHD prophylaxis. Syngeneic (CB6F1) SCT did not cure any of the mice and KGF treatment did not influence tumor development. After transplantation with haploidentical (B6CBAF1) bone marrow and splenocytes, however, tumor outgrowth was reduced and long-term disease-free survival (>3 months) was observed in 9/18 (50%) (P=0.0011) of the animals. We conclude that in a model of murine breast cancer, a graft-versus-tumor effect can be induced by a nonmyeloablative haploidentical SCT procedure.

Expression of aberrantly glycosylated tumor mucin-1 on human DC after transduction with a fiber-modified adenoviral vector.

BACKGROUND: DC-presenting tumor Ag are currently being developed to be used as a vaccine in human cancer immunotherapy. To increase chances for successful therapy it is important to deliver full-length tumor Ag instead of loading single peptides. METHODS: In this study we used a fiber-modified adenoviral vector (rAd5F35) containing full-length tumor Ag cDNA to transduce human monocyte (Mo)-derived DC in vitro. Cells were efficiently transduced and survived for at least 3 days after adenoviral transduction. Phenotype and function after maturation of Mo-DC were not impaired by infection with adenovirus particles. Expression of the tumor-associated Ag mucin-1 (MUC1) was detected using MAb defining different MUC1 glycoforms. RESULTS: Non-transduced mature Mo-DC express endogenous MUC1 with normal glycosylation. After transduction with the rAd5F35-MUC1 adenoviral vector, Mo-DC also expressed MUC1 with tumor-associated glycosylation (Tn and T glycoforms), although no changes in mRNA levels of relevant glycosyltransferases could be demonstrated. DISCUSSION: The presence of aberrantly glycosylated MUC1 may influence Ag presentation of the tumor glycoforms of MUC1 to immune cells, affecting tumor cell killing. These findings could be highly relevant to developing strategies for cancer immunotherapy based on DC vaccines using MUC1 as tumor Ag.

Transduction with a fiber-modified adenoviral vector is superior to non-viral nucleofection for expressing tumor-associated Ag mucin-1 in human DC.

BACKGROUND: DC-presenting tumor Ag are currently being developed to be used as a vaccine in human cancer immunotherapy. To increase the chances for successful therapy it is important to deliver full-length tumor Ag instead of loading single peptides. Methodologically, several recombinant DNA delivery techniques have been used. METHODS: In this study we compared nucleofection, an optimized form of electroporation, and adenoviral transduction regarding their efficiency to transduce human monocyte-derived (Mo-) DC in vitro. Expression of the tumor-associated Ag mucin-1 (MUC1) after adenoviral transduction (rAd5Fib35-MUC1) was determined using two MAb. RESULTS: We showed that the viability of cells and percentage of green fluorescent protein (GFP)-positive cells after transduction with a fiber-modified adenoviral vector (rAd5F35-GFP) was much higher than after nucleofection. Furthermore, phenotype and function of DC were not impaired by infection with adenovirus particles. Cells matured normally; up-regulation of CD40, CD80, CD83, CD86 and HLA-DR was not affected by adenoviral transduction. The capacity to stimulate naive T-cell proliferation was preserved and no change in IL-10 production was observed. Production of IL-12 increased up to 500-fold upon adenoviral transduction, considered to contribute positively to an anti-tumor immune response. Non-transduced mature DC expressed low levels of endogenous MUC1. After transduction with the rAd5F35-MUC1 adenoviral vector, a 100-fold increase in MUC1 expression by DC was observed. DISCUSSION: The use of the fiber-modified adenoviral vector presented here may therefore be favorable compared with non-viral gene delivery systems for DC that will be used in cancer immunotherapy.

Oral anticoagulant treatment with coumarin derivatives does not influence plasma homocysteine concentration.

BACKGROUND: High circulating levels of homocysteine are a risk factor for arterial and venous thrombosis. This association has been established in numerous case-control studies. In some of these studies, patients were treated with anticoagulants at the time of venapuncture. It is not clear whether homocysteine concentrations are influenced by anticoagulants. If anticoagulation does, indeed, have an effect on homocysteine levels, it might underestimate or overestimate the possible association of homocysteine levels and vascular disease. METHODS: In this study we used two different groups to investigate the effect of coumarin derivatives on homocysteine concentrations. Homocysteine levels were measured in 40 patients who were on the waiting list for orthopedic surgery and who were expected to receive prophylactic anticoagulant therapy after the operation. Measurements were taken before the operation, as well as during and after coumarin therapy. Homocysteine concentrations were also measured in a second study group consisting of 12 healthy volunteers who were treated with oral anticoagulants. RESULTS: Mean homocysteine concentrations increased by 6% (95% CI 2-10%) during the treatment with coumarin derivatives. This corresponds to a 1 mumol/L increase in homocysteine concentration. After the anticoagulant treatment period, the concentrations decreased again. We determined that this slight increase does not influence the interpretation of epidemiological studies. We also observed no significant effect of anticoagulants on homocysteine concentration after 13 weeks of treatment of healthy volunteers (decrease of 3.6%, or approximately 0.6 micromol/L; 95% CI -17.5-8.5%). CONCLUSION: We conclude that anticoagulation does not influence homocysteine concentrations to any significant degree.

Keratinocyte growth factor ameliorates acute graft-versus-host disease in a novel nonmyeloablative haploidentical transplantation model.

Allogeneic stem cell transplantations (SCT) are currently being used as a therapy for hematological malignancies, some solid tumors and nonmalignant bone marrow deficiencies. Nevertheless, clinical applicability is limited due to toxicity of conditioning regimens, graft-versus-host disease (GVHD) and the scarcity of HLA-identical family donors. New concepts are based on nonmyeloablative conditioning to reduce toxicity, prevention or amelioration of GVHD and the use of haploidentical donors to increase donor availability. To combine these requirements, we have developed a nonmyeloablative conditioning regimen, consisting of low-dose total body irradiation and cyclophosphamide-based chemotherapy. In a haploidentical F1 --> F1 mouse model, this nonmyeloablative transplantation protocol resulted in stable full donor chimerism, but also in the development of severe GVHD. Administration of keratinocyte growth factor (KGF) reduced GVHD, evident as reduced weight loss and a lesser degree of dermatitis, compared to saline-treated controls. KGF preserved plasma citrulline and tumor necrosis factor-alpha levels, both indicative for reduced injury to the gastrointestinal tract. This was confirmed by histological findings. At 6 months after transplantation, survival rates were significantly higher in KGF-treated animals as compared to phosphate buffered saline-treated controls. These results indicate that KGF preserves gut integrity and might therefore contribute substantially to reduction of lethal GVHD in (nonmyeloablative) haploidentical transplantation.

[Modern treatment methods for multiple myeloma: guidelines from the Dutch Haemato-Oncology Association (HOVON)]. / De moderne behandeling van het multipel myeloom: een richtlijn van de Stichting Hemato-Oncologie voor Volwassenen Nederland (HOVON).

The treatment for multiple myeloma has undergone many changes over the past decade. Intensive therapy with autologous stem-cell support has improved the clinical outcome significantly in younger patients. Reduced intensity conditioning regimens have lowered the high treatment-related mortality of myeloablative allogeneic transplantation. New effective anti-myeloma drugs such as bortezomib and thalidomide analogues have become available. These new developments have made it necessary to formulate recommendations to facilitate decisions concerning the management of myeloma patients. The Myeloma Working Party of the Dutch Haemato-Oncology Association (Stichting Haemato-Oncologie voor Volwassenen Nederland) has developed therapy guidelines based on phase-II and phase-III studies as well as the expertise of the working party. These include upfront induction therapy followed by autologous transplantation for patients aged up to 65 years and oral melphalanprednisone treatment for patients with severe co-morbidities and patients over the age of 65 years. Patients under the age of 66 with an HLA-identical (family) donor are candidates for non-myeloablative stem-cell transplantation following autologous stem-cell transplantation. For second-line treatment, thalidomide, combined with dexamethasone is recommended. Younger patients responding to second-line treatment are candidates for a second autologous transplant. Bortezomib is indicated for those patients refractory to the previous two lines of treatment. All patients should receive long-term bisphosphonates. Erythropoietin may be considered in symptomatic anaemia as well as antibiotic prophylaxis during induction therapy which includes dexamethasone.

Advantages and limitations of (non-)myeloablative allogeneic stem cell transplantation.

Allogeneic stem cell transplantation (allo-SCT) is the treatment of choice for a variety of malignant diseases, not only as a method to regain haematopoiesis after myeloablative therapy, but also for its apparent antitumour effect. However, treatment-related morbidity and mortality are considerable. A potential way to overcome this problem is by decreasing the intensity of chemotherapy and/or radiotherapy given prior to transplantation. This reduced-intensity conditioning regimen is the basis of non-myeloablative allo-SCT (also referred to as mini SCT), a new treatment modality that relies more heavily on the antitumour effect exerted by the donor cells than on the antitumour effect of the conditioning therapy. The aim of this article is to place the concept of non-myeloablative SCT in a historical context and to discuss the advantages and disadvantages of regular myeloablative SCT compared with non-myeloablative SCT. Furthermore, human trials regarding non-myeloablative SCT are reviewed, and several experimental techniques are discussed that aim to augment the antitumour effect of an allogeneic graft.

Non-myeloablative allogeneic stem cell transplantation in patients with solid tumours and patients with a haematological malignancy.

Allogeneic stem cell transplantation (allo-SCT) is a treatment option for several haematological tumours, not only to regain haematopoiesis after myeloablative chemotherapy and/or radiotherapy, but also for its apparent antitumour effect. This so-called graft-versus-tumour effect might not only be effective against haematological tumours, where it has best been proven, but also against solid tumours. To reduce morbidity and treatment-related mortality of allo-SCT, efforts are being made to establish engraftment of allogeneic stem cells after a non-myeloablative conditioning regimen and create a 'mini transplantation'. Such a therapy relies more heavily on the graft-versus-malignancy effect than on the antitumour effect exerted by the chemotherapy/radiotherapy. Here, we report the outcomes of 15 patients with haematological disease or solid tumours who underwent an SCT in the University Hospital Maastricht after a non-myeloablative fludarabine/cyclophosphamide conditioning regimen. Although results are promising, adjustments will be needed to ensure long-term stable engraftment and optimise the antitumour effect.