title: Three-dimensional (3D) tumor spheroid invasion assay.
abstract: Invasion of surrounding normal tissues is generally considered to be a key hallmark of malignant (as opposed to benign) tumors. For some cancers in particular (e.g., brain tumors such as glioblastoma multiforme and squamous cell carcinoma of the head and neck - SCCHN) it is a cause of severe morbidity and can be life-threatening even in the absence of distant metastases. In addition, cancers which have relapsed following treatment unfortunately often present with a more aggressive phenotype. Therefore, there is an opportunity to target the process of invasion to provide novel therapies that could be complementary to standard anti-proliferative agents. Until now, this strategy has been hampered by the lack of robust, reproducible assays suitable for a detailed analysis of invasion and for drug screening. Here we provide a simple micro-plate method (based on uniform, self-assembling 3D tumor spheroids) which has great potential for such studies. We exemplify the assay platform using a human glioblastoma cell line and also an SCCHN model where the development of resistance against targeted epidermal growth factor receptor (EGFR) inhibitors is associated with enhanced matrix-invasive potential. We also provide two alternative methods of semi-automated quantification: one using an imaging cytometer and a second which simply requires standard microscopy and image capture with digital image analysis.
authors.affiliation: Division of Molecular Pathology, The Institute of Cancer Research; Division of Cancer Therapeutics, The Institute of Cancer Research; maria.vinci@icr.ac.uk.
authors.forename: Maria
authors.initials: M
authors.lastname: Vinci
authors.affiliation: Division of Cancer Therapeutics, The Institute of Cancer Research.
authors.forename: Carol
authors.initials: C
authors.lastname: Box
authors.affiliation: Division of Cancer Therapeutics, The Institute of Cancer Research.
authors.forename: Suzanne A
authors.initials: SA
authors.lastname: Eccles
mesh_terms: D000818:Animals; D001932:Brain Neoplasms / Q000473:pathology*; D002294:Carcinoma, Squamous Cell / Q000473:pathology*; D018929:Cell Culture Techniques / Q000379:methods*; D045744:Cell Line, Tumor; D005909:Glioblastoma / Q000473:pathology*; D006258:Head and Neck Neoplasms / Q000473:pathology*; D006801:Humans; D051379:Mice; D009361:Neoplasm Invasiveness; D018874:Spheroids, Cellular / Q000473:pathology; D000077195:Squamous Cell Carcinoma of Head and Neck