Functional Proteomics Approach to Investigate the Biological Activities of cDNAs Implicated in Breast Cancer

Functional proteomics approaches that comprehensively evaluate the biological activities of human
cDNAs may provide novel insights into disease pathogenesis. To systematically investigate the
functional activity of cDNAs that have been implicated in breast carcinogenesis, we generated a
collection of cDNAs relevant to breast cancer, the Breast Cancer 1000 (BC1000), and conducted screens
to identify proteins that induce phenotypic changes that resemble events which occur during tumor
initiation and progression. Genes were selected for this set using bioinformatics and data mining tools
that identify genes associated with breast cancer. Greater than 1000 cDNAs were assembled and
sequence verified with high-throughput recombination-based cloning. To our knowledge, the BC1000
represents the first publicly available sequence-validated human disease gene collection. The functional
activity of a subset of the BC1000 collection was evaluated in cell-based assays that monitor changes
in cell proliferation, migration, and morphogenesis in MCF-10A mammary epithelial cells expressing
a variant of ErbB2 that can be inducibly activated through dimerization. Using this approach, we
identified many cDNAs, encoding diverse classes of cellular proteins, that displayed activity in one or
more of the assays, thus providing insights into a large set of cellular proteins capable of inducing
functional alterations associated with breast cancer development.
Keywords: functional proteomics • breast cancer • cell-based assay • cDNA expression • proliferation • migration
• invasion • acinar morphogenesis • BC1000 • high-throughput