Basic techniques for the use of reverse phase protein microarrays for signal pathway profiling

Ultimately, disease-related genetic defects are manifested on a protein level, involving derangements in protein function and the information flow within diseased cells and the surrounding tissue microenvironment. New classes of protein microarrays have been recently developed using highly sensitive, specific technology, and can be used to generate a “wiring diagram” of information flow mediated through posttranslational modification driven networks. Through the combined use of laser capture microdissection of pure populations of tumor cells obtained from patient biopsies, these arrays can provide the foundation for the development of individualized combinatorial therapies of molecular inhibitors to target tumor-specific deranged pathways regulating key biologic processes including proliferation, differentiation, apoptosis, immunity, and metastasis. In the future, therapies can be tailored to the specific deranged molecular circuitry of an individual patient's disease. The successful transition of these technologies from research tools to integrated clinical diagnostic platforms will require ongoing continued development, development of reference standards, and optimization with rigorous standardization development and quality-control procedures.