Willeke Blokx

Willeke Blokx

orcid

Research Focus & Metrics

Academic Career Length

27Years (2000-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
20 April 2007 in Journal of Clinical Oncology
Verified
Journal Article
Closed access
NSNancy J. Senff
Nancy J. Senff
JHJuliette J. Hoefnagel
Juliette J. Hoefnagel
PJPatty M. Jansen
Patty M. Jansen
Maarten VermeerMaarten Vermeer
Maarten Vermeer
JBJoop van Baarlen
Joop van Baarlen
RWRein Willemze
Rein Willemze
Purpose: In the new WHO–European Organisation for Research and Treatment of Cancer (WHO-EORTC) classification for cutaneous lymphomas three major groups of primary cutaneous B-cell lymphoma (CBCL) are distinguished: primary cutaneous marginal zone B-cell lymphoma (PCMZL) and primary cutaneous follicle center lymphoma (PCFCL) with a good prognosis, and primary cutaneous large B-cell lymphoma, leg type (PCLBCL-LT), with an intermediate-level prognosis. This study aimed to assess the clinical significance of the new classification compared with previous classification schemes (EORTC 1997; WHO 2001) and to define prognostic factors within the newly defined categories. Patients and Methods: In the present study clinical data and histologic sections of 300 patients with CBCL, formerly classified according to the EORTC classification, were reviewed and reclassified according to the WHO and the new WHO-EORTC classification schemes. Results: After reclassification, the study comprised 71 patients with PCMZL, 171 patients with PCFCL, and 58 patients with PCLBCL-LT, showing 5-year disease-specific survivals of 98%, 95%, and 50%, respectively. When compared with the EORTC and WHO schemes, 5.3% and 36.3% of patients with CBCL were reclassified into another prognostic category. Multivariate analysis of PCFCL revealed localization on the leg and expression of FOXP1 as independent parameters associated with a poor prognosis. Expression of Bcl-2 or MUM-1 had no significant effect on survival in this group. In PCLBCL-LT, no independent prognostic parameters were found. Conclusion: These results emphasize the clinical significance of the WHO-EORTC classification, but suggest that within the group of PCFCL, distinction should be made between lymphomas presenting on the legs and lymphomas presenting at other sites.

1 December 2005 in Journal of Investigative Dermatology
Verified
Journal Article
Closed access
PDF file
GJGys J. de Jongh
Gys J. de Jongh
PZPatrick Zeeuwen
Patrick Zeeuwen
MKMartina Kucharekova
Martina Kucharekova
RPRolph Pfundt
Rolph Pfundt
PVPieter G. van der Valk
Pieter G. van der Valk
JSJoost Schalkwijk
Joost Schalkwijk

1 May 2016 in Clinical Cancer Research
Verified
Journal Article
Closed access
PDF file
GSGerty Schreibelt
Gerty Schreibelt
KBKalijn Bol
Kalijn Bol
HWHarm Westdorp
Harm Westdorp
FWFlorian Wimmers
Florian Wimmers
EAErik H.J.G. Aarntzen
Erik H.J.G. Aarntzen
IVI. Jolanda M. De Vries
I. Jolanda M. De Vries
Purpose: Thus far, dendritic cell (DC)-based immunotherapy of cancer was primarily based on in vitro–generated monocyte-derived DCs, which require extensive in vitro manipulation. Here, we report on a clinical study exploiting primary CD1c+ myeloid DCs, naturally circulating in the blood. Experimental Design: Fourteen stage IV melanoma patients, without previous systemic treatment for metastatic disease, received autologous CD1c+ myeloid DCs, activated by only brief (16 hours) ex vivo culture and loaded with tumor-associated antigens of tyrosinase and gp100. Results: Our results show that therapeutic vaccination against melanoma with small amounts (3–10 × 106) of myeloid DCs is feasible and without substantial toxicity. Four of 14 patients showed long-term progression-free survival (12–35 months), which directly correlated with the development of multifunctional CD8+ T-cell responses in three of these patients. In particular, high CD107a expression, indicative for cytolytic activity, and IFNγ as well as TNFα and CCL4 production was observed. Apparently, these T-cell responses are essential to induce tumor regression and promote long-term survival by stalling tumor growth. Conclusions: We show that vaccination of metastatic melanoma patients with primary myeloid DCs is feasible and safe and results in induction of effective antitumor immune responses that coincide with improved progression-free survival. Clin Cancer Res; 22(9); 2155–66. ©2015 AACR.

1 April 2009 in Clinical Cancer Research
Verified
Journal Article
Open access
PDF file
PVPauline Verdijk
Pauline Verdijk
EAErik Aarntzen
Erik Aarntzen
WLW. Joost Lesterhuis
W. Joost Lesterhuis
ABA.C. Inge Boullart
A.C. Inge Boullart
EKEllemieke Kok
Ellemieke Kok
IVI. Jolanda M. De Vries
I. Jolanda M. De Vries
Purpose: The success of immunotherapy with dendritic cells (DC) to treat cancer is dependent on effective migration to the lymph nodes and subsequent activation of antigen-specific T cells. In this study, we investigated the fate of DC after intradermal (i.d.) or intranodal (i.n.) administration and the consequences for the immune activating potential of DC vaccines in melanoma patients.

1 January 2013 in Cancer Research
Verified
Journal Article
Closed access
EAErik H.J.G. Aarntzen
Erik H.J.G. Aarntzen
IVI. Jolanda M. De Vries
I. Jolanda M. De Vries
WLW. Joost Lesterhuis
W. Joost Lesterhuis
DSDanita Schuurhuis
Danita Schuurhuis
JJJoannes F.M. Jacobs
Joannes F.M. Jacobs
CFCarl Figdor
Carl Figdor
To evaluate the relevance of directing antigen-specific CD4+ T helper cells as part of effective anticancer immunotherapy, we investigated the immunologic and clinical responses to vaccination with dendritic cells (DC) pulsed with either MHC class I (MHC-I)–restricted epitopes alone or both MHC class I and II (MHC-I/II)–restricted epitopes. We enrolled 33 stage III and IV HLA-A*02:01–positive patients with melanoma in this study, of whom 29 were evaluable for immunologic response. Patients received intranodal vaccinations with cytokine-matured DCs loaded with keyhole limpet hemocyanin and MHC-I alone or MHC-I/II–restricted tumor-associated antigens (TAA) of tyrosinase and gp100, depending on their HLA-DR4 status. In 4 of 15 patients vaccinated with MHC-I/II–loaded DCs and 1 of 14 patients vaccinated with MHC-I–loaded DCs, we detected TAA-specific CD8+ T cells with maintained IFN-γ production in skin test infiltrating lymphocyte (SKIL) cultures and circulating TAA-specific CD8+ T cells. If TAA-specific CD4+ T-cell responses were detected in SKIL cultures, it coincided with TAA-specific CD8+ T-cell responses. In 3 of 13 patients tested, we detected TAA-specific CD4+CD25+FoxP3− T cells with high proliferative capacity and IFN-γ production, indicating that these were not regulatory T cells. Vaccination with MHC-I/II–loaded DCs resulted in improved clinical outcome compared with matched control patients treated with dacarbazine (DTIC), median overall survival of 15.0 versus 8.3 months (P = 0.089), and median progression-free survival of 5.0 versus 2.8 months (P = 0.0089). In conclusion, coactivating TAA-specific CD4+ T-helper cells with DCs pulsed with both MHC class I and II–restricted epitopes augments TAA-specific CD8+ T-cell responses, contributing to improved clinical responses. Cancer Res; 73(1); 19–29. ©2012 AACR.

22 November 2009 in Acta Neuropathologica
Verified
Journal Article
Open access
PDF file
HKHeidi V. N. Küsters-Vandevelde
Heidi V. N. Küsters-Vandevelde
AKAnnelies Klaasen
Annelies Klaasen
BKBenno Küsters
Benno Küsters
PGPatricia J. T. A. Groenen
Patricia J. T. A. Groenen
IGIlse A. C. H. van Engen-Van Grunsven
Ilse A. C. H. van Engen-Van Grunsven
WBWilleke Blokx
Willeke Blokx
Primary melanocytic neoplasms of the central nervous system (CNS) are uncommon neoplasms derived from melanocytes that normally can be found in the leptomeninges. They cover a spectrum of malignancy grades ranging from low-grade melanocytomas to lesions of intermediate malignancy and overtly malignant melanomas. Characteristic genetic alterations in this group of neoplasms have not yet been identified. Using direct sequencing, we investigated 19 primary melanocytic lesions of the CNS (12 melanocytomas, 3 intermediate-grade melanocytomas, and 4 melanomas) for hotspot oncogenic mutations commonly found in melanocytic tumors of the skin (BRAF, NRAS, and HRAS genes) and uvea (GNAQ gene). Somatic mutations in the GNAQ gene at codon 209, resulting in constitutive activation of GNAQ, were detected in 7/19 (37%) tumors, including 6/12 melanocytomas, 0/3 intermediate-grade melanocytomas, and 1/4 melanomas. These GNAQ-mutated tumors were predominantly located around the spinal cord (6/7). One melanoma carried a BRAF point mutation that is frequently found in cutaneous melanomas (c.1799 T>A, p.V600E), raising the question whether this is a metastatic rather than a primary tumor. No HRAS or NRAS mutations were detected. We conclude that somatic mutations in the GNAQ gene at codon 209 are a frequent event in primary melanocytic neoplasms of the CNS. This finding provides new insight in the pathogenesis of these lesions and suggests that GNAQ-dependent mitogen-activated kinase signaling is a promising therapeutic target in these tumors. The prognostic and predictive value of GNAQ mutations in primary melanocytic lesions of the CNS needs to be determined in future studies.