Janneke D M Molkenboer-Kuenen

Radboud University Nijmegen, Nijmegen, Provincie Gelderland, Netherlands

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Publications (11)61.46 Total impact

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    ABSTRACT: The aim was to assess changes in insulin-like growth factor 1 receptor (IGF-1R) expression with immunoSPECT/CT and to study the dynamics of IGF-1R expression of human breast tumors during endocrine treatment. Mice with MCF-7 xenografts were treated with estradiol or tamoxifen, and IGF-1R expression was measured by immunohistochemistry and immunoSPECT/CT using (111)In-R1507 (anti-IGF-1R antibody). Moreover, IGF-1R expression was analyzed immunohistochemically on 22 human breast tumors, treated preoperatively with endocrine therapy. Estradiol resulted in an increased expression of IGF-1R, as measured by immunohistochemistry and immunoSPECT/CT. In contrast, tamoxifen resulted in a downregulation of IGF-1R, whereas this could not be measured with immunoSPECT/CT. A downregulation was also detectable in 9 out of 22 (41 %) human breast tumors after endocrine therapy. Anti-estrogen treatment can cause a reduction in membranous IGF-1R expression. Based on these results, a combination of anti-IGF-1R antibodies with anti-estrogen therapy might not be a rational treatment strategy.
    Molecular imaging and biology: MIB: the official publication of the Academy of Molecular Imaging 02/2014; · 2.47 Impact Factor
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    ABSTRACT: PURPOSE: To investigate whether F(ab')2-fragments of the monoclonal Insulin-like Growth Factor-1 Receptor (IGF-1R) antibody R1507 (F(ab')2-R1507) can successfully target IGF-1R in Ewing sarcomas (ES). MATERIALS AND METHODS: BALB/c nude mice were subcutaneously implanted with IGF-1R-expressing human ES xenografts (EW-5 and EW-8) which previously showed heterogeneous or no uptake of indium-111-labelled R1507 IgG ((111)In-R1507), respectively. Mice were injected with (111)In-F(ab')2-R1507 or (111)In-R1507 as a reference. Biodistribution and immuno-SPECT/computed tomography (CT) imaging studies were carried out 2, 4, 8 and 24h post-injection (p.i.) for (111)In-F(ab')2-R1507 and 24h p.i. for (111)In-R1507. RESULTS: Biodistribution studies showed specific accumulation of (111)In-F(ab')2-R1507 in EW-5 xenografts from t=2h p.i. onwards (3.6±0.2%ID/g at t=24h p.i.) and (111)In-F(ab')2-R1507 immuno-SPECT showed almost homogeneous intratumoural distribution at t=24h p.i. Tumour-to-blood ratios of (111)In-F(ab')2-R1507 were significantly higher than those of (111)In-R1507 at t=24h p.i. (2.4±0.4 versus 0.5±0.1, respectively; p<0.05). More importantly, (111)In-F(ab')2-R1507 also specifically accumulated in EW-8 tumours (3.7±0.7%ID/g at t=24h p.i). In both EW-5 and EW-8 tumours, there was a good spatial correlation between IGF-1R expression and (111)In-F(ab')2-R1507 tumour distribution. CONCLUSION: (111)In-F(ab')2-R1507 fragments can successfully target IGF-1R in ES models and have superior tumour penetrating and IGF-1R-targeting properties as compared to (111)In-R1507. This suggests that anti-IGF-1R therapies in ES and other tumours may be improved by using smaller therapeutic compounds, although further in vivo studies addressing this topic are warranted.
    European journal of cancer (Oxford, England: 1990) 05/2013; · 4.12 Impact Factor
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    ABSTRACT: Bevacizumab (anti-VEGF) and cetuximab (anti-EGFR) are approved antibodies for treatment of cancer. However, in advanced colorectal cancer, the combination fails to improve survival. As the reason for the lack of activity is unknown, this study aims to determine the effect of bevacizumab on targeting of anti-EGFR and IGF-1R antibodies in tumors with SPECT/CT imaging. Mice with subcutaneous EGFR and IGF-1R-expressing SUM149 xenografts received a single dose of bevacizumab (10 mg/kg) or saline. After four days, mice were injected with radiolabeled cetuximab or R1507, an anti-IGF-1R antibody. A control group received a radiolabeled irrelevant IgG (hLL2). Three days later, SPECT/CT images were acquired and mice were dissected to determine the concentration of antibodies in the tissues. Tumors were analyzed immunohistochemically to determine vascular density (CD34), VEGF, EGFR and IGF-1R expression. SPECT/CT imaging revealed that bevacizumab treatment significantly reduced tumor targeting of radiolabeled cetuximab by 40% from 33.1 ± 1.1 %ID/g to 19.8 ± 5.7 %ID/g (p = 0.009) for untreated and bevacizumab treated tumors, respectively. A similar effect was found for (111) In-R1507: tumor targeting of R1507 decreased by 35%. No significant differences in tumor uptake were observed in mice that received an irrelevant IgG. Uptake in normal organs was not altered by bevacizumab. Immunohistochemical analysis showed that vascular density decreased with 43%, while EGFR and IGF-1R expression was unaltered. In conclusion, bevacizumab treatment significantly reduces tumor targeting of anti-EGFR and anti-IGF-1R antibodies. This emphasizes the importance of timing and sequencing of bevacizumab in combination with other antibodies.
    International Journal of Cancer 01/2013; · 6.20 Impact Factor
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    ABSTRACT: Clinical application of calcium phosphate cement (CPC; with incorporated polymeric porogens) in an injectable form implicates that loading methods for growth factors are limited. In view of this, the current study evaluated the in vitro and in vivo release kinetics of bone morphogenetic protein-2 (BMP-2) loaded on poly(d,l-lactic-co-glycolic acid) (PLGA) microparticles (CPC/PLGA), BMP-2 incorporation into the liquid phase of CPC (CPC/liquid), and BMP-2 absorbed to the surface of preset, porous CPC (CPC/surface) as a control via an in vitro release experiment and in vivo using microSPECT imaging with (125)I-labeled BMP-2. In addition, the osteoinductive capacity of scaffolds generated via the different BMP-2 loading methods was assessed in a subcutaneous rat model. Additional controls consisted of porous CPC scaffolds (CPC/porous) and CPC/PLGA (CPC/control) without BMP-2 loading. The results revealed that it is feasible to load BMP-2 into CPC via adsorption to PLGA-microparticles or the liquid phase of CPC, which resulted in a similar release profile over the course of 28days, despite distinct protein distribution patterns. Compared to CPC-scaffolds with surface-loaded BMP-2, these loading methods showed a similar release profile, except for a significantly decreased burst release. As such, the observed osteoinductive capacity for only CPC-scaffolds with surface-loaded BMP-2 is likely to be related to this difference in burst release. It remains unclear to what extent the differential BMP-2 loading methods for injectable CPC can affect the biological response in a bone environment.
    Journal of Controlled Release 07/2012; · 7.63 Impact Factor
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    ABSTRACT: The insulin-like growth factor 1 receptor (IGF-1R) is a potential new target for the treatment of breast cancer. Patients with breast cancer lesions that express IGF-1R may benefit from treatment with anti-IGF-1R antibodies. IGF-1R expression can be visualized using radiolabeled R1507, a monoclonal antibody directed against IGF-1R. However, antibodies clear slowly from the circulation, resulting in low tumor-to-background ratios early after injection. Therefore, we aimed to accelerate targeting of IGF-1R using radiolabeled R1507 F(ab')(2) and Fab fragments. In vitro, immunoreactivity, binding affinity and internalization of R1507 IgG, F(ab')(2) and Fab were determined using the triple negative IGF-1R-expressing breast cancer cell line SUM149. In vivo, pharmacokinetics of (111)In-labeled R1507 IgG, F(ab')(2) and Fab were studied in mice bearing subcutaneous SUM149 xenografts. SPECT/CT images were acquired and the biodistribution was measured ex vivo. The in vitro binding characteristics of radiolabeled R1507 IgG and F(ab')(2) were comparable, whereas the affinity of Fab fragments was significantly lower (K(d): 0.6 nM, 0.7 nM and 3.0 nM for R1507 IgG, F(ab')(2) and Fab, respectively). Biodistribution studies showed that the maximum tumor uptake of (111)In-R1507 IgG, F(ab')(2) and Fab was 31.8% ID/g (72 h p.i.), 10.0% ID/g (6 h p.i.), and 1.8% ID/g (1 h p.i.), respectively. However, maximal tumor-to-blood ratios for F(ab')(2) (24 h p.i.: 7.5) were more than twice as high as those obtained with R1507 (72 h p.i.: 2.8) and Fab (6 h p.i.: 2.8). Injection of an excess of unlabeled R1507 significantly reduced tumor uptake, suggesting that the uptake of R1507 IgG and F(ab')(2) was specific for IGF-1R, while the major fraction of the tumor uptake of Fab was nonspecific. IGF-1R-expressing xenografts were visualized with (111)In-F(ab')(2) SPECT/CT as early as 6 h p.i., while with R1507 IgG, the tumor could be visualized after 24 h. No specific targeting was observed with (111)In-Fab. (111)In-F(ab')(2) fragments showed improved targeting of IGF-1R expressing tumors. Tumor-to-blood ratios were twice as high as those obtained with (111)In-R1507, and adequate tumor targeting on SPECT/CT images was observed as early as 6 h p.i. For individualization and optimization of IGF-1R targeted therapy, (111)In-F(ab')(2) may be the tracer of choice.
    Molecular Pharmaceutics 07/2012; · 4.57 Impact Factor
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    ABSTRACT: To investigate whether indium-111-labeled R1507 ((111)In-R1507) immuno-SPECT (single-photon emission computed tomography), a novel noninvasive, in vivo screening method to visualize membranous insulin-like growth factor 1 receptor (IGF-1R) expression and accessibility, can be used to predict IGF-1R treatment (R1507) response in bone sarcomas. BALB/c nude mice were subcutaneously implanted with IGF-1R-expressing human bone sarcoma xenografts (OS-1, EW-5, and EW-8) which showed high, modest, or no response, respectively, to R1507, a monoclonal antibody targeting the extracellular domain of IGF-1R. An IGF-1R-negative tumor (OS-33), unresponsive to IGF-1R inhibitors, was examined as well. Mice were injected with (111)In-R1507. Biodistribution and immuno-SPECT/computed tomography imaging studies were carried out 1, 3, and 7 days p.i. in mice with OS-1 and EW-5 xenografts and 3 days p.i. in mice with EW-8 and OS-33 xenografts. Biodistribution studies showed specific accumulation of (111)In-R1507 in OS-1 and EW-5 xenografts (27.5 ± 6.5%ID/g and 14.0 ± 2.8%ID/g, 3 days p.i., respectively). Most importantly, (111)In-R1507 uptake in IGF-1R positive, but unresponsive, EW-8 xenografts (6.5 ± 1.5%ID/g, 3 days p.i.) was similar to that of the IGF-1R-negative OS-33 tumor (5.5 ± 0.6%ID/g, 3 days p.i.). Uptake in normal tissues was low and nonspecific. Corresponding immuno-SPECT images clearly discriminated between high, modest, and nonresponding tumors by showing a homogeneous (OS-1), heterogeneous (EW-5), or nonspecific (EW-8 and OS-33) tumor uptake of (111)In-R1507. (111)In-R1507 immuno-SPECT is an excellent method to visualize membranous IGF-1R expression and target accessibility in vivo in human bone sarcoma xenografts and may serve as an independent marker to predict IGF-1R therapy (R1507) response in bone sarcoma patients.
    Clinical Cancer Research 12/2011; 17(24):7693-703. · 7.84 Impact Factor
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    ABSTRACT: The insulinlike growth factor 1 receptor (IGF-1R) is a new target for the treatment of breast cancer. Patients with breast cancer lesions that express IGF-1R may benefit from treatment with anti-IGF-1R antibodies. Therefore, the aim of the present study was to develop a noninvasive, in vivo imaging method, using radiolabeled antibodies, to visualize IGF-1R expression. R1507 is a monoclonal antibody directed against the IGF-1R. In vitro, the affinity and internalization kinetics of (111)In-R1507 were determined using the IGF-1R-expressing triple-negative breast cancer cell line SUM149. In vivo, the pharmacodynamics of (111)In-R1507 and (125)I-R1507 were determined in mice with subcutaneous SUM149 tumors. (111)In-R1507 SPECT and (89)Zr-R1507 PET images of mice with subcutaneous SUM149 tumors were acquired at 1, 3, and 7 d after injection. (111)In-R1507 (concentration required to inhibit binding by 50%, 0.1 nM) was slowly internalized by SUM149 cells. (111)In-R1507 specifically and efficiently accumulated in the SUM149 xenografts: the tumor uptake was 20 percentage injected dose per gram (%ID/g), 33 %ID/g, and 31 %ID/g at 1, 3, and 7 d after injection, respectively. (125)I-R1507 accumulated in the tumor less efficiently. Small-animal SPECT and small-animal PET of mice clearly visualized the subcutaneous SUM149 xenograft, with increasing contrast at later time points. (111)In-R1507 and (89)Zr-R1507 are new tracers to noninvasively determine IGF-1R expression in vivo in breast cancer xenografts using SPECT and PET. In the future, these techniques may enable patient selection for IGF-1R-targeted therapy.
    Journal of Nuclear Medicine 10/2010; 51(10):1565-72. · 5.77 Impact Factor
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    ABSTRACT: Noninvasive imaging of the epidermal growth factor receptor (EGFR) in head-and-neck squamous cell carcinoma could be of value to select patients for EGFR-targeted therapy. We assessed dose optimization of (111) Indium-DTPA-cetuximab ((111) In-cetuximab) for EGFR imaging in a head-and-neck squamous cell carcinoma xenograft model. (111) In-cetuximab slowly internalized into FaDu cells in vitro, amounting to 1.0 × 10(4) molecules cetuximab per cell after 24 hr (15.8% of added activity). In nude mice with subcutaneous FaDu xenograft tumors, a protein dose escalation study with (111) In-cetuximab showed highest specific accumulation in tumors at protein doses between 1 and 30 μg per mouse (mean tumor uptake 33.1 ± 3.1%ID/g, 3 days postinjection (p.i.)). The biodistribution of (111) In-cetuximab and (125) I-cetuximab was determined at 1, 3 and 7 days p.i. at optimal protein dose. Tumor uptake was favorable for (111) In-cetuximab compared to (125) I-cetuximab. With pixel-by-pixel analysis, good correlations were found between intratumoral distribution of (111) In-cetuximab as determined by autoradiography and EGFR expression in the same tumor sections as determined immunohistochemically (mean r = 0.74 ± 0.14; all correlations p < 0.0001). Micro Single Photon Emission Computed Tomography (MicroSPECT) scans clearly visualized FaDu tumors from 1 day p.i. onward and tumor-to-background contrast increased until 7 days p.i. (tumor-to-liver ratios 0.58 ± 0.24, 3.42 ± 0.66, 8.99 ± 4.66 and 16.33 ± 11.56, at day 0, day 1, day 3 and day 7 p.i., respectively). Our study suggests that, at optimal cetuximab imaging dose, (111) In-cetuximab can be used for visualization of EGFR expression in head-and-neck squamous cell carcinoma using SPECT.
    International Journal of Cancer 10/2010; 129(4):870-8. · 6.20 Impact Factor
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    ABSTRACT: To enable preclinical testing of intravesical therapies against non-muscle-invasive bladder cancer (NMIBC) in an orthotopic rat bladder tumour model, augmented by the use of serial cystoscopy for in vivo tumour assessment and follow-up. Fischer F344 rats had a 16-G transurethral cannula placed. The bladder mucosa was conditioned with an acid rinse, followed by a 1-h instillation of 1.5 x 10(6) AY-27 rat bladder urothelial cell carcinoma (UCC) cells (day 0). Cystoscopy (1 mm) was done on day 0 (control) and at 3, 4, 5, 6, 7, 10, 13 and 17 days. At the scheduled times the rats were killed after cystectomy (four at each time) for histopathological examination of the bladder. Overall, tumour establishment was >80%, with predominantly carcinoma in situ preceding or concomitant with invasive tumour growth. All tumours were formed at 3-5 days, and remained non-muscle-invasive up to 5 days. From 6 days, tumours progressed to muscle-invasive disease in 40% of the rats. Visibility at cystoscopy was excellent and tumours were apparent in >90% of rats from 5 days on, with a specificity and sensitivity of >90%. Cystoscopy could not distinguish NMIBC from muscle-invasive disease. This is a reliable model of orthotopic rat bladder UCC, with early high-grade NMIBC growth, immediately followed by muscle-invasive growth, i.e. the recommended time to start intravesical therapy would be 5 days after tumour cell inoculation. Tumour growth can easily be monitored by cystoscopy, but cannot be used to distinguish NMIBC from muscle-invasive bladder cancer.
    BJU International 04/2008; 101(7):889-93. · 3.05 Impact Factor
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    ABSTRACT: In search for a new drug for intravesical use in superficial urothelial cell carcinoma of the bladder, a pig model is used for pharmacokinetics and toxicity measurements after intravesically administered pemetrexed. In the dose escalation phase, two groups of two pigs received 5 and 10 mg/kg pemetrexed intravesically; four groups of three pigs received 15, 20, 25, and 30 mg/kg, respectively. The well-being of the animals was monitored. Blood was studied for pharmacokinetic analysis and signs of myelosuppression. Posttreatment urine samples were collected to measure the concentration of pemetrexed after instillation. Twenty-four hours posttreatment, the animals were cystectomized and sacrificed. Histopathologic examination of the bladder wall was done. In the second study phase, five pigs were instilled weekly with the maximum tested dose for 6 weeks. The same methods were applied. All doses (5-30 mg/kg) in the first study phase were well tolerated, enabling the use of 30 mg/kg in the second study phase. In both study phases, the pigs' well-being was not influenced. Full blood counts showed no sign of myelosuppression. Systemic absorption was not observed. Urine pemetrexed concentrations remained almost unchanged. Histopathologic examination of the bladder wall did not reveal significant abnormalities. Bladder mucosa remained intact at any time, without hemorrhage. Intravesically administered pemetrexed in pigs is well tolerated, not absorbed systemically, and causes no bladder wall toxicity.
    Clinical Cancer Research 05/2006; 12(8):2597-601. · 7.84 Impact Factor
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    ABSTRACT: We have developed an efficient pretargeting strategy for renal cell carcinoma (RCC) based on a biologically produced bispecific monoclonal antibody (bs-mAb). Tumor targeting with this 2-step pretargeting strategy in the NU-12 mouse RCC model was very efficient compared with other pretargeting strategies, possibly due to unique characteristics of the NU-12 tumor used in our studies. Here we describe the bs-mAb G250xDTIn-1 pretargeting strategy in 3 different RCC nude mouse models. Three different human RCC xenografts in nude mice (NU-12, SK-RC-1, and SK-RC-52 tumors) were pretargeted with 100 pmol bs-mAb G250xDTIn-1. Three days after administration of the bs-mAb, mice were injected intravenously with 4 pmol 111In-labeled bivalent peptide, diDTPA-FKYK (DTPA is diethylenetriaminepentaacetic acid). At 1, 4, 24, 48, and 72 h after injection of the radiolabeled peptide, the biodistribution of the radiolabel was determined. The 3 RCC tumors were characterized in vivo and in vitro for G250 antigen expression, vessel density, vascular volume, and vascular permeability and by targeting with 111In-/125I-labeled cG250 mAb. Using the pretargeting strategy, relatively high uptake of the radiolabel was observed in all 3 tumor models (maximum uptake: SK-RC-1 [278 +/- 130 %ID/g (percentage injected dose per gram), 1 h after injection] > NU-12 [93 +/- 41 %ID/g, 72 h after injection] > SK-RC-52 [54 +/- 9 %ID/g, 4 h after injection]). Remarkably, uptake of the radiolabel in the tumor did not correlate with G250 antigen expression. The kinetics of the radiolabel in the tumor varied largely in the 3 RCC tumors: SK-RC-1 and SK-RC-52 tumors showed a washout of the 111In label from the tumor with time: only 30% of the radiolabel was retained in the tumor 3 d after injection, whereas the 111In label was fully retained in NU-12 tumors. Physiologic characteristics (vessel density, vascular volume, and vascular permeability) of the tumors may explain these differences. G250 antigen-expressing tumors can be pretargeted very efficiently with the bs-mAb G250xDTIn-1. There was no correlation between G250 antigen expression and uptake of the radiolabel in the tumor using the pretargeting strategy or with directly labeled mAbs. Therefore, these studies show that physiologic characteristics of the tumor, such as vascular permeability, play a significant role in pretargeting.
    Journal of Nuclear Medicine 04/2005; 46(3):495-501. · 5.77 Impact Factor

Publication Stats

75 Citations
61.46 Total Impact Points


  • 2010–2012
    • Radboud University Nijmegen
      • Department of Medical Oncology
      Nijmegen, Provincie Gelderland, Netherlands
  • 2005–2008
    • Radboud University Medical Centre (Radboudumc)
      • Department of Human Genetics
      Nymegen, Gelderland, Netherlands