BACKGROUND:Cell lines represent a key tool in cancer research allowing the generation of neoplasias in in-vivo animal models resembling the initial tumours.
The characterisation of early tumour development is of major interest to evaluate intervening agents. MRI based in-vivo characterisation allows the visualisation and characterisation of tumour development in early stages prior to palpation. MRI imaging contrast agents as e.g. superparamagnetic iron oxide nanoparticles (SPIOs) or manganese chloride (MnCl2) can be a powerful tool for the characterisation of early stage tumours in-vivo. We directly labelled in-vitro cells with MnCl2 or SPIOs and used 1T MRI as well as 7T MRI based tracing of prostate cancer cells in-vitro and in an in-vivo animal model.
METHODS:Labelling of prostate cancer cells CT1258 was established in-vitro with MnCl2 and SPIOs. In-vitro detection of labelled cells was performed in an agar phantom in a 1T MRI system while in-vivo detection was performed using a 7T MRI after subcutaneous (sc) injections of labelled cells into NOD-Scid mice (n=20). The animals were scanned regularly until euthanization. The respective tumour volumes were analysed and tumour masses characterised histologically.
RESULTS:MnCl2 in-vitro labelling revealed no significant metabolic effects on proliferation and cell viability. In-vitro detection-limit accounted 105 cells for MnCl2 as well as SPIOs labelling. In-vivo 7T MRI scans allowed detection of 103 and 104 cells. In-vivo MnCl2 labelled cells were detectable from days 4-16 while SPIO labelling allowed detection till 4 days after s.c. injection. MnCl2 labelled cells were highly tumourigenic in NOD-Scid mice and the tumour volume development was characterised in time dependent manner. The number of injected cells correlated with tumour size development and disease progression. Histological analysis of the induced tumour masses revealed characteristic morphology of a prostate adenocarcinoma.
CONCLUSIONS: This is the first study reporting direct in-vitro MnCl2 labelling and 7T based in-vivo MRI tracing of cancer cells in a model of prostate cancer. MnCl2 labelling was found to be appropriate for in-vivo tracing allowing long detection periods. The labelled cells kept their highly tumourigenic potential in-vivo. Tumour volume development was visualised prior to palpation allowing a tumour characterisation in early stages.
Written by:
Sterenczak KA, Meier M, Glage S, Meyer M, Willenbrock S, Wefstaedt P, Dorsch M, Bullerdiek J, Murua Escobar H, Hedrich H, Nolte I. Are you the author?
Reference: BMC Cancer. 2012 Jul 11;12(1):284.
doi: 10.1186/1471-2407-12-284
PubMed Abstract
PMID: 22784304
UroToday.com Investigative Urology Section
