Protein Microarrays - A Promising Tool for Cancer Diagnosis

Within recent years, protein microarrays have been developed to quantify a large number of parameters present in a given sample simultaneously. Such miniaturised and parallelised sandwich immunoassays are of general interest for all proteomic and diagnostic approaches in which several parameters have to be determined from small samples, e.g. biopsy material. In addition to planar microarray-based approaches, bead-based flow cytometry is quite suitable for the multiplex detection of target molecules, especially when a limited number of parameters are to be analysed. Appropriate sensitivity, reproducibility and robustness have to be demonstrated before protein microarray technology can be used to characterise clinical samples and generate reliable data sets. As a model system to analyse these issues, a set of multiplexed sandwich immunoassays based on Luminex beads were developed to screen clinical samples for the presence or absence of marker proteins indicative of prognosis or response to therapeutic options.