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Dive into the research topics where Henk M. Lokhorst is active.

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Featured researches published by Henk M. Lokhorst.


Journal of Clinical Oncology | 2012

Bortezomib Induction and Maintenance Treatment in Patients With Newly Diagnosed Multiple Myeloma: Results of the Randomized Phase III HOVON-65/ GMMG-HD4 Trial

Pieter Sonneveld; Ingo G.H. Schmidt-Wolf; Bronno van der Holt; Laila el Jarari; Uta Bertsch; Hans Salwender; Sonja Zweegman; Edo Vellenga; Annemiek Broyl; Igor Wolfgang Blau; Katja Weisel; Shulamiet Wittebol; Gerard M. J. Bos; Marian Stevens-Kroef; Christof Scheid; Michael Pfreundschuh; Dirk Hose; Anna Jauch; Helgi van der Velde; Reinier Raymakers; Martijn R. Schaafsma; M. J. Kersten; Marinus van Marwijk-Kooy; Ulrich Duehrsen; Walter Lindemann; Pierre W. Wijermans; Henk M. Lokhorst; Hartmut Goldschmidt

PURPOSE We investigated whether bortezomib during induction and maintenance improves survival in newly diagnosed multiple myeloma (MM). PATIENTS AND METHODS In all, 827 eligible patients with newly diagnosed symptomatic MM were randomly assigned to receive induction therapy with vincristine, doxorubicin, and dexamethasone (VAD) or bortezomib, doxorubicin, and dexamethasone (PAD) followed by high-dose melphalan and autologous stem-cell transplantation. Maintenance consisted of thalidomide 50 mg (VAD) once per day or bortezomib 1.3 mg/m(2) (PAD) once every 2 weeks for 2 years. The primary analysis was progression-free survival (PFS) adjusted for International Staging System (ISS) stage. RESULTS Complete response (CR), including near CR, was superior after PAD induction (15% v 31%; P < .001) and bortezomib maintenance (34% v 49%; P < .001). After a median follow-up of 41 months, PFS was superior in the PAD arm (median of 28 months v 35 months; hazard ratio [HR], 0.75; 95% CI, 0.62 to 0.90; P = .002). In multivariate analysis, overall survival (OS) was better in the PAD arm (HR, 0.77; 95% CI, 0.60 to 1.00; P = .049). In high-risk patients presenting with increased creatinine more than 2 mg/dL, bortezomib significantly improved PFS from a median of 13 months to 30 months (HR, 0.45; 95% CI, 0.26 to 0.78; P = .004) and OS from a median of 21 months to 54 months (HR, 0.33; 95% CI, 0.16 to 0.65; P < .001). A benefit was also observed in patients with deletion 17p13 (median PFS, 12 v 22 months; HR, 0.47; 95% CI, 0.26 to 0.86; P = .01; median OS, 24 months v not reached at 54 months; HR, 0.36; 95% CI, 0.18 to 0.74; P = .003). CONCLUSION Bortezomib during induction and maintenance improves CR and achieves superior PFS and OS.


Journal of Immunology | 2011

Daratumumab, a Novel Therapeutic Human CD38 Monoclonal Antibody, Induces Killing of Multiple Myeloma and Other Hematological Tumors

Michel de Weers; Yu-Tzu Tai; Michael S. van der Veer; Joost M. Bakker; Tom Vink; Daniëlle C. H. Jacobs; Lukas A. Oomen; Matthias Peipp; Thomas Valerius; Jerry W. Slootstra; Tuna Mutis; Wim K. Bleeker; Kenneth C. Anderson; Henk M. Lokhorst; Jan G. J. van de Winkel; Paul Parren

CD38, a type II transmembrane glycoprotein highly expressed in hematological malignancies including multiple myeloma (MM), represents a promising target for mAb-based immunotherapy. In this study, we describe the cytotoxic mechanisms of action of daratumumab, a novel, high-affinity, therapeutic human mAb against a unique CD38 epitope. Daratumumab induced potent Ab-dependent cellular cytotoxicity in CD38-expressing lymphoma- and MM-derived cell lines as well as in patient MM cells, both with autologous and allogeneic effector cells. Daratumumab stood out from other CD38 mAbs in its strong ability to induce complement-dependent cytotoxicity in patient MM cells. Importantly, daratumumab-induced Ab-dependent cellular cytotoxicity and complement-dependent cytotoxicity were not affected by the presence of bone marrow stromal cells, indicating that daratumumab can effectively kill MM tumor cells in a tumor-preserving bone marrow microenvironment. In vivo, daratumumab was highly active and interrupted xenograft tumor growth at low dosing. Collectively, our results show the versatility of daratumumab to effectively kill CD38-expressing tumor cells, including patient MM cells, via diverse cytotoxic mechanisms. These findings support clinical development of daratumumab for the treatment of CD38-positive MM tumors.


Leukemia | 2009

International myeloma working group consensus statement and guidelines regarding the current role of imaging techniques in the diagnosis and monitoring of multiple Myeloma

Meletios A. Dimopoulos; E Terpos; Raymond L. Comenzo; Patrizia Tosi; Meral Beksac; Orhan Sezer; David Siegel; Henk M. Lokhorst; Shaji Kumar; S V Rajkumar; Ruben Niesvizky; L A Moulopoulos; Brian G. M. Durie

Several imaging technologies are used for the diagnosis and management of patients with multiple myeloma (MM). Conventional radiography, computed tomography (CT), magnetic resonance imaging (MRI) and nuclear medicine imaging are all used in an attempt to better clarify the extent of bone disease and soft tissue disease in MM. This review summarizes all available data in the literature and provides recommendations for the use of each of the technologies. Conventional radiography still remains the ‘gold standard’ of the staging procedure of newly diagnosed and relapsed myeloma patients. MRI gives information complementary to skeletal survey and is recommended in MM patients with normal conventional radiography and in all patients with an apparently solitary plasmacytoma of bone. Urgent MRI or CT (if MRI is not available) is the diagnostic procedure of choice to assess suspected cord compression. Bone scintigraphy has no place in the routine staging of myeloma, whereas sequential dual-energy X-ray absorptiometry scans are not recommended. Positron emission tomography/CT or MIBI imaging are also not recommended for routine use in the management of myeloma patients, although both techniques may be useful in selected cases that warrant clarification of previous imaging findings, but such an approach should ideally be made within the context of a clinical trial.


Blood | 2010

A randomized phase 3 study on the effect of thalidomide combined with adriamycin, dexamethasone, and high-dose melphalan, followed by thalidomide maintenance in patients with multiple myeloma

Henk M. Lokhorst; B. van der Holt; Sonja Zweegman; Edo Vellenga; Sandra Croockewit; M. H. J. Van Oers; P.A. von dem Borne; P. Wijermans; Ron Schaafsma; O. de Weerdt; S. Wittebol; Michel Delforge; Henriette W Berenschot; G. Bos; Kon-Siong G. Jie; Harm Sinnige; M. van Marwijk-Kooy; Peter Joosten; Monique C. Minnema; R. van Ammerlaan; Pieter Sonneveld

The phase 3 trial HOVON-50 was designed to evaluate the effect of thalidomide during induction treatment and as maintenance in patients with multiple myeloma who were transplant candidates. A total of 556 patients was randomly assigned to arm A: 3 cycles of vincristine, adriamycin, and dexamethasone, or to arm B: thalidomide 200 mg orally, days 1 to 28 plus adriamycin and dexamethasone. After induction therapy and stem cell mobilization, patients were to receive high-dose melphalan, 200 mg/m(2), followed by maintenance with alpha-interferon (arm A) or thalidomide 50 mg daily (arm B). Thalidomide significantly improved overall response rate as well as quality of the response before and after high dose melphalan. Best overall response rate on protocol was 88% and 79% (P = .005), at least very good partial remission 66% and 54% (P = .005), and complete remission 31% and 23% (P = .04), respectively, in favor of the thalidomide arm. Thalidomide also significantly improved event-free survival from median 22 months to 34 months (P < .001), and prolonged progression free from median 25 months to 34 months (P < .001). Median survival was longer in the thalidomide arm, 73 versus 60 months; however, this difference was not significant (P = .77). Patients randomized to thalidomide had strongly reduced survival after relapse. This trial was registered on www.controlled-trials.com as ISRCTN06413384.


Blood | 2012

Administration of bortezomib before and after autologous stem cell transplantation improves outcome in multiple myeloma patients with deletion 17p

Kai Neben; Henk M. Lokhorst; Anna Jauch; Uta Bertsch; Thomas Hielscher; Bronno van der Holt; Hans Salwender; Igor Wolfgang Blau; Katja Weisel; Michael Pfreundschuh; Christof Scheid; Ulrich Dührsen; Walter Lindemann; Ingo G.H. Schmidt-Wolf; Norma Peter; Christian Teschendorf; Hans Martin; Mathias Haenel; Hans Günter Derigs; Marc S. Raab; Anthony D. Ho; Helgi van de Velde; Dirk Hose; Pieter Sonneveld; Hartmut Goldschmidt

In patients with multiple myeloma (MM), risk stratification by chromosomal abnormalities may enable a more rational selection of therapeutic approaches. In the present study, we analyzed the prognostic value of 12 chromosomal abnormalities in a series of 354 MM patients treated within the HOVON-65/GMMG-HD4 trial. Because of the 2-arm design of the study, we were able to analyze the effect of a bortezomib-based treatment before and after autologous stem cell transplantation (arm B) compared with standard treatment without bortezomib (arm A). For allanalyzed chromosomal aberrations, progression-free survival (PFS) and overall survival (OS) were at least equal or superior in the bortezomib arm compared with the standard arm. Strikingly, patients with del(17p13) benefited the most from the bortezomib-containing treatment: the median PFS in arm A was 12.0 months and in arm B it was 26.2 months (P = .024); the 3 year-OS for arm A was 17% and for arm B it was 69% (P = .028). After multivariate analysis, del(17p13) was an independent predictor for PFS (P < .0001) and OS (P < .0001) in arm A, whereas no statistically significant effect on PFS (P = .28) or OS (P = .12) was seen in arm B. In conclusion, the adverse impact of del(17p13) on PFS and OS could be significantly reduced by bortezomib-based treatment, suggesting that long-term administration of bortezomib should be recommended for patients carrying del(17p13).


Journal of Clinical Oncology | 2010

Phase III Study of the Value of Thalidomide Added to Melphalan Plus Prednisone in Elderly Patients With Newly Diagnosed Multiple Myeloma: The HOVON 49 Study

Pierre W. Wijermans; Martijn R. Schaafsma; Fabian Termorshuizen; Rianne Ammerlaan; Shulamiet Wittebol; Harm Sinnige; Sonja Zweegman; Marinus van Marwijk Kooy; René van der Griend; Henk M. Lokhorst; Pieter Sonneveld

PURPOSE For several decades, the treatment of elderly patients with multiple myeloma (MM) has consisted of melphalan and prednisone (MP). The Dutch-Belgium Hemato-Oncology Cooperative Group (HOVON) investigated the efficacy of thalidomide added to MP (MP-T) in a randomized phase III trial. The objective of this study was to investigate the efficacy, toxicity, and effects on quality of life of MP-T. PATIENTS AND METHODS A randomized phase III trial compared standard MP with MP-T (thalidomide 200 mg/d) in newly diagnosed patients with multiple myeloma older than age 65 years. Maintenance therapy with thalidomide 50 mg/d was administered to patients after MP-T until relapse. The primary end point was event-free survival (EFS); response rate, overall survival (OS), and progression-free survival (PFS) were secondary end points. RESULTS An intent-to-treat analysis of 333 evaluable patients showed significantly higher response rates in MP-T-treated patients compared with MP-treated patients a response (> or = partial response: 66% v 45%, respectively; P < .001; and > or = very good partial response [VGPR]: 27% v 10%, respectively; P < .001). EFS was 13 months with MP-T versus 9 months with MP (P < .001). OS was 40 months with MP-T versus 31 months with MP (P = .05). CONCLUSION This study demonstrates that thalidomide improves the response rate and VGPR in elderly patients with newly diagnosed MM. MP-T also results in a better EFS, PFS, and OS.


Blood | 2011

Personalized therapy in multiple myeloma according to patient age and vulnerability: a report of the European Myeloma Network (EMN)

A. Palumbo; Sara Bringhen; Heinz Ludwig; Meletios A. Dimopoulos; Joan Bladé; M.V. Mateos; Laura Rosiñol; Mario Boccadoro; Michele Cavo; Henk M. Lokhorst; Sonja Zweegman; Evangelos Terpos; Faith E. Davies; Christoph Driessen; Peter Gimsing; Martin Gramatzki; Roman Hájek; Hans Erik Johnsen; F. Leal da Costa; Orhan Sezer; Andrew Spencer; Meral Beksac; Gareth J. Morgan; Hermann Einsele; J. F. San Miguel; Pieter Sonneveld

Most patients with newly diagnosed multiple myeloma (MM) are aged > 65 years with 30% aged > 75 years. Many elderly patients are also vulnerable because of comorbidities that complicate the management of MM. The prevalence of MM is expected to rise over time because of an aging population. Most elderly patients with MM are ineligible for autologous transplantation, and the standard treatment has, until recently, been melphalan plus prednisone. The introduction of novel agents, such as thalidomide, bortezomib, and lenalidomide, has improved outcomes; however, elderly patients with MM are more susceptible to side effects and are often unable to tolerate full drug doses. For these patients, lower-dose-intensity regimens improve the safety profile and thus optimize treatment outcome. Further research into the best treatment strategies for vulnerable elderly patients is urgently needed. Appropriate screening for vulnerability and an assessment of cardiac, pulmonary, renal, hepatic, and neurologic functions, as well as age > 75 years, at the start of therapy allows treatment strategies to be individualized and drug doses to be tailored to improve tolerability and optimize efficacy. Similarly, occurrence of serious nonhematologic adverse events during treatment should be carefully taken into account to adjust doses and optimize outcomes.


Journal of Clinical Investigation | 2008

Misfolded proteins activate Factor XII in humans, leading to kallikrein formation without initiating coagulation

Coen Maas; José W. P. Govers-Riemslag; Barend Bouma; Bettina Schiks; Bouke Hazenberg; Henk M. Lokhorst; Per Hammarström; Hugo ten Cate; Philip G. de Groot; Bonno N. Bouma; Martijn F. B. G. Gebbink

When blood is exposed to negatively charged surface materials such as glass, an enzymatic cascade known as the contact system becomes activated. This cascade is initiated by autoactivation of Factor XII and leads to both coagulation (via Factor XI) and an inflammatory response (via the kallikrein-kinin system). However, while Factor XII is important for coagulation in vitro, it is not important for physiological hemostasis, so the physiological role of the contact system remains elusive. Using patient blood samples and isolated proteins, we identified a novel class of Factor XII activators. Factor XII was activated by misfolded protein aggregates that formed by denaturation or by surface adsorption, which specifically led to the activation of the kallikrein-kinin system without inducing coagulation. Consistent with this, we found that Factor XII, but not Factor XI, was activated and kallikrein was formed in blood from patients with systemic amyloidosis, a disease marked by the accumulation and deposition of misfolded plasma proteins. These results show that the kallikrein-kinin system can be activated by Factor XII, in a process separate from the coagulation cascade, and point to a protective role for Factor XII following activation by misfolded protein aggregates.


Blood | 2010

Gene expression profiling for molecular classification of multiple myeloma in newly diagnosed patients

Annemiek Broyl; Dirk Hose; Henk M. Lokhorst; Yvonne de Knegt; Justine K. Peeters; Anna Jauch; Uta Bertsch; Arjan Buijs; Marian Stevens-Kroef; H. Berna Beverloo; Edo Vellenga; Sonja Zweegman; Marie-Josee Kersten; Bronno van der Holt; Laila el Jarari; George Mulligan; Hartmut Goldschmidt; Pieter Sonneveld

To identify molecularly defined subgroups in multiple myeloma, gene expression profiling was performed on purified CD138(+) plasma cells of 320 newly diagnosed myeloma patients included in the Dutch-Belgian/German HOVON-65/GMMG-HD4 trial. Hierarchical clustering identified 10 subgroups; 6 corresponded to clusters described in the University of Arkansas for Medical Science (UAMS) classification, CD-1 (n = 13, 4.1%), CD-2 (n = 34, 1.6%), MF (n = 32, 1.0%), MS (n = 33, 1.3%), proliferation-associated genes (n = 15, 4.7%), and hyperdiploid (n = 77, 24.1%). Moreover, the UAMS low percentage of bone disease cluster was identified as a subcluster of the MF cluster (n = 15, 4.7%). One subgroup (n = 39, 12.2%) showed a myeloid signature. Three novel subgroups were defined, including a subgroup of 37 patients (11.6%) characterized by high expression of genes involved in the nuclear factor kappa light-chain-enhancer of activated B cells pathway, which include TNFAIP3 and CD40. Another subgroup of 22 patients (6.9%) was characterized by distinct overexpression of cancer testis antigens without overexpression of proliferation genes. The third novel cluster of 9 patients (2.8%) showed up-regulation of protein tyrosine phosphatases PRL-3 and PTPRZ1 as well as SOCS3. To conclude, in addition to 7 clusters described in the UAMS classification, we identified 3 novel subsets of multiple myeloma that may represent unique diagnostic entities.


Lancet Oncology | 2010

Mechanisms of peripheral neuropathy associated with bortezomib and vincristine in patients with newly diagnosed multiple myeloma: a prospective analysis of data from the HOVON-65/GMMG-HD4 trial.

Annemiek Broyl; Sophie L. Corthals; Joost L. M. Jongen; Bronno van der Holt; Rowan Kuiper; Yvonne de Knegt; Laila el Jarari; Uta Bertsch; Henk M. Lokhorst; Brian G. M. Durie; Hartmut Goldschmidt; Pieter Sonneveld

BACKGROUND Bortezomib-induced peripheral neuropathy is a dose-limiting toxicity in patients with multiple myeloma, often requiring adjustment of treatment and affecting quality of life. We investigated the molecular profiles of early-onset (within one treatment cycle) versus late-onset (after two or three treatment cycles) bortezomib-induced peripheral neuropathy and compared them with those of vincristine-induced peripheral neuropathy during the induction phase of a prospective phase 3 trial. METHODS In the induction phase of the HOVON-65/GMMG-HD4 trial, patients (aged 18-65 years) with newly diagnosed Salmon and Durie stage 2 or 3 multiple myeloma were randomly assigned to three cycles of bortezomib-based or vincristine-based induction treatment. We analysed the gene expression profiles and single-nucleotide polymorphisms (SNPs) of pretreatment samples of myeloma plasma cells and peripheral blood, respectively. This study is registered, number ISRCTN64455289. FINDINGS We analysed gene expression profiles of myeloma plasma cells from 329 (39%) of 833 patients at diagnosis, and SNPs in DNA samples from 369 (44%) patients. Early-onset bortezomib-induced peripheral neuropathy was noted in 20 (8%) patients, and 63 (25%) developed the late-onset type. Early-onset and late-onset vincristine-induced peripheral neuropathy was noted in 11 (4%) and 17 (7%) patients, respectively. Significant genes in myeloma plasma cells from patients that were associated with early-onset bortezomib-induced peripheral neuropathy were the enzyme coding genes RHOBTB2 (upregulated by 1·59 times; p=4·5×10(-5)), involved in drug-induced apoptosis, CPT1C (1·44 times; p=2·9×10(-7)), involved in mitochondrial dysfunction, and SOX8 (1·68 times; p=4·28×10(-13)), involved in development of peripheral nervous system. Significant SNPs in the same patients included those located in the apoptosis gene caspase 9 (odds ratio [OR] 3·59, 95% CI 1·59-8·14; p=2·9×10(-3)), ALOX12 (3·50, 1·47-8·32; p=3·8×10(-3)), and IGF1R (0·22, 0·07-0·77; p=8·3×10(-3)). In late-onset bortezomib-induced peripheral neuropathy, the significant genes were SOD2 (upregulated by 1·18 times; p=9·6×10(-3)) and MYO5A (1·93 times; p=3·2×10(-2)), involved in development and function of the nervous system. Significant SNPs were noted in inflammatory genes MBL2 (OR 0·49, 95% CI 0·26-0·94; p=3·0×10(-2)) and PPARD (0·35, 0·15-0·83; p=9·1×10(-3)), and DNA repair genes ERCC4 (2·74, 1·56-4·84; p=1·0×10(-3)) and ERCC3 (1·26, 0·75-2·12; p=3·3×10(-3)). By contrast, early-onset vincristine-induced peripheral neuropathy was characterised by upregulation of genes involved in cell cycle and proliferation, including AURKA (3·31 times; p=1·04×10(-2)) and MKI67 (3·66 times; p=1·82×10(-3)), and the presence of SNPs in genes involved in these processes-eg, GLI1 (rs2228224 [0·13, 0·02-0·97, p=1·18×10(-2)] and rs2242578 [0·14, 0·02-1·12, p=3·00×10(-2)]). Late-onset vincristine-induced peripheral neuropathy was associated with the presence of SNPs in genes involved in absorption, distribution, metabolism, and excretion-eg, rs1413239 in DPYD (3·29, 1·47-7·37, 5·40×10(-3)) and rs3887412 in ABCC1 (3·36, 1·47-7·67, p=5·70×10(-3)). INTERPRETATION Our results strongly suggest an interaction between myeloma-related factors and the patients genetic background in the development of treatment-induced peripheral neuropathy, with different molecular pathways being implicated in bortezomib-induced and vincristine-induced peripheral neuropathy.

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Tuna Mutis

Leiden University Medical Center

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Sonja Zweegman

VU University Medical Center

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Bronno van der Holt

Erasmus University Rotterdam

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