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Updated: Jun 9, 2026
In vivo Imaging of Tumor Angiogenesis using Fluorescence Confocal Videomicroscopy
Published on: September 11, 2013
Molecular imaging of VEGF in gastrointestinal cancer in vivo using confocal laser endomicroscopy
Sebastian Foersch1, Ralf Kiesslich, Maximillian J Waldner
1Medical Clinic I, University of Mainz, Mainz, Germany.
Background:
Vascular endothelial growth factor (VEGF) is a therapeutic target in gastrointestinal cancer (GiC). However, its in vivo visualisation could not be achieved to date with endoscopic techniques. Confocal laser endomicroscopy (CLE) is a novel imaging technique for gastrointestinal endoscopy providing in vivo microscopy at subcellular resolution. The aim of the study was to evaluate CLE for in vivo molecular imaging of VEGF in GiC.
Methods:
Molecular imaging of tumours in APCmin mice, in xenograft models and in surgical specimens of patients with colorectal cancer (CRC) was achieved after application of labelled antibodies. The tumour sites were scanned with the probe for the strongest specific fluorescent signal. From all tumour sites examined with CLE in vivo, targeted specimens were obtained for histology, immunohistochemistry (IHC) and fluorescence microscopy.
Results:
A VEGF-specific signal was visualised in vivo in 13/15 APCmin mice and in 9/10 xenograft tumours. CLE enabled the cytoplasmatic distribution of VEGF to be displayed due to its subcellular resolution. In human tissue, a VEGF-specific signal was observed in 12/13 malignant specimens and in 10/11 samples from healthy mucosa from the patients (p<0.03). CLE findings correlated well with ex vivo microscopy.
Conclusion:
In vivo molecular imaging with specific targeting of VEGF is possible in murine tumours, human xenografts and tissue specimens using CLE. CLE with similar probes can be performed in human colonoscopy. Therefore-from a technical point of view-in vivo molecular imaging is transferable to stratification of patients with CRC during endoscopy even today. CLE could contribute to the identification of lesions at risk and potentially predict response to targeted treatment.
Insights
Confocal laser endomicroscopy (CLE) allows in vivo molecular imaging of vascular endothelial growth factor (VEGF) in gastrointestinal cancers. This technique enables patient stratification and potential prediction of treatment response during colonoscopy.
Area of Science:
- Gastroenterology
- Oncology
- Medical Imaging
Background:
- Vascular endothelial growth factor (VEGF) is a key therapeutic target in gastrointestinal cancer (GiC).
- Current endoscopic techniques lack the ability for in vivo visualization of VEGF.
- Confocal laser endomicroscopy (CLE) offers subcellular resolution for in vivo gastrointestinal imaging.
Purpose of the Study:
- To evaluate the efficacy of CLE for in vivo molecular imaging of VEGF in GiC.
- To assess the potential of CLE for patient stratification in colorectal cancer (CRC).
Main Methods:
- Labeled antibodies targeting VEGF were applied to tumors in APCmin mice, xenograft models, and human CRC specimens.
- Tumor sites were scanned using CLE to detect specific fluorescent signals.
- CLE findings were correlated with histology, immunohistochemistry (IHC), and ex vivo fluorescence microscopy.
Main Results:
- VEGF-specific signals were visualized in vivo in murine tumors (13/15 APCmin mice, 9/10 xenografts) and human tissues (12/13 malignant, 10/11 healthy mucosa).
- CLE's subcellular resolution allowed visualization of cytoplasmic VEGF distribution.
- CLE findings demonstrated strong correlation with ex vivo microscopy.
Conclusions:
- In vivo molecular imaging of VEGF using CLE is feasible in preclinical models and human tissues.
- CLE is technically transferable to human colonoscopy for molecular imaging.
- CLE holds potential for patient stratification and predicting treatment response in CRC.
