5 July 2019

In Theranostics Mark Rijpkema and colleagues developed a novel multimodal tracer that targets PSMA-expressing prostate cancer and allows both preoperative imaging for diagnosis and staging, surgical guidance by intraoperative fluorescence imaging, and targeted photodynamic therapy of any remaining tumor cells after resection.

Abstract

Rationale
Prostate cancer (PCa) recurrences after surgery frequently occur. To improve the outcome after surgical resection of the tumor, the theranostic multimodal anti-PSMA targeting agent 111In-DTPA-D2B-IRDye700DX was developed and characterized for both pre- and intra-operative tumor localization and eradication of (residual) tumor tissue by PSMA-targeted photodynamic therapy (tPDT), which is a highly selective cancer treatment based on targeting molecules conjugated to photosensitizers that can induce cell destruction upon exposure to near-infrared (NIR) light.
Methods
The anti-PSMA monoclonal antibody D2B was conjugated with IRDye700DX and DTPA and subsequently radiolabeled with 111In. To determine the optimal dose and time point for tPDT, BALB/c nude mice with PSMA-expressing (PSMA+) s.c. LS174T-PSMA xenografts received the conjugate (24-240 µg/mouse) intravenously (8 MBq/mouse) followed by µSPECT/CT, near-infrared fluorescence imaging, and ex vivo biodistribution at 24, 48, 72 and 168 h p.i. Tumor growth of LS174T-PSMA xenografts and overall survival of mice treated with 1-3 times of NIR light irradiation (50, 100, 150 J/cm2) 24 h after injection of 80 µg of DTPA-D2B-IRDye700DX was compared to control conditions.
Results
Highest specific tumor uptake was observed at conjugate doses of 80 µg/mouse. Biodistribution revealed no significant difference in tumor uptake in mice at 24, 48, 72 and 168 h p.i. PSMA+ tumors were clearly visualized with both µSPECT/CT and NIR fluorescence imaging. Overall survival in mice treated with 80 µg of DTPA-D2B-IRDye700DX and 1x 150 J/cm2 of NIR light at 24 h p.i. was significantly improved compared to the control group receiving neither conjugate nor NIR light (73 days vs. 16 days, respectively, p=0.0453). Treatment with 3x 150 J/cm2 resulted in significantly prolonged survival compared to treatment with 3x 100 J/cm2 (p = 0.0067) and 3x 50 J/cm2 (p = 0.0338). Principal conclusions: 111In-DTPA-D2B-IRDye700DX can be used for pre- and intra-operative detection of PSMA+ tumors with radionuclide and NIR fluorescence imaging and PSMA-targeted PDT. PSMA-tPDT using this multimodal agent resulted in significant prolongation of survival and shows great potential for treatment of (metastasized) prostate cancer.

Publication
Development and characterization of a theranostic multimodal anti-PSMA targeting agent for imaging, surgical guidance, and targeted photodynamic therapy of PSMA-expressing tumors.
Lütje S, Heskamp S, Franssen GM, Frielink C, Kip A, Hekman M, Fracasso G, Colombatti M, Herrmann K, Boerman OC, Gotthardt M, Rijpkema M.

Mark Rijpkema is member of theme Urological cancers.
  • Want to know more about these subjects? Click on the buttons below for more news.

    RIMLSRIHSResearch

Related news items


Bart van de Warrenburg appointed visiting professor at the UKM Medical Centre in Kuala Lumpur

11 November 2019

Neurologist and Principal Investigator at the Donders Institute Bart van de Warrenburg has been appointed visiting professor at the UKM Medical Centre in Kuala Lumpur.

read more

KNAW Van Leersum beurs for Mohammad Alsady

7 November 2019

Mohammad Alsady, theme Disorders of movement, received the “KNAW Van Leersum beurs”.

read more

3D breast ultrasound elastography to improve breast cancer detection

5 November 2019

One out of seven women will be diagnosed with breast cancer during their life. Early detection of breast cancer is important to increase the survival rate. Gijs Hendriks graduated recently on a new technique, 3D elastography, to detect breast cancer better.

read more

Self-management rehabilitation program improves participation in patients with neuromuscular disease

4 November 2019

Yvonne Veenhuizen, Alexander Geurts theme Neurorehabilitation, Baziel van Engelen, theme Disorders of movement, and colleagues, showed that Energetic improves participation in patients with neuromuscular disease. They have published their results in Neurology.

read more

New NFU eBROK® course open for registration

1 November 2019

This platform is not only for researchers who want to obtain their BROK® certificate, but also for researchers who already have a BROK® certificate and want to keep their certification (re-certification).

read more

Emily Klooster wins the NVZF incentive prize

31 October 2019

For the second year in a row, a PhD candidate from the Allied Health Sciences group of IQ Healthcare (RIHS), has won the "Dutch Association for Physiotherapists in the Hospital" incentive prize.

read more