Our group is involved in developing novel biotechnologies to solve difficult biological problems. The focus of the work has been in the field of Proteomics and Cancer Research. Proteomics involves the study of the protein expression of a cell, where proteins are the entities that perform the functions of the cell. Our work has involved developing methods to profile large numbers of proteins expressed by cancer cells and to understand how these proteins are different than those observed from normal cells. Proteins that are modified or overexpressed in cancer cells often result in new protein pathways that lead to tumorogenesis and metastasis of the cancer.
We have developed a total liquid 2-dimensional separations method based upon isoelectric focusing in the first phase followed by nonporous RP HPLC to generate an image of the protein content of a cell lysate. The proteins in the liquid phase can then be analyzed by electrospray-TOF mass spectrometry to produce a molecular weight map of the proteins in the cell up to 100 kDa. In addition, tryptic mapping and MALDI-TOF MS can be used to identify proteins against various computer DNA databases. The result is that comparisons can be made between different cancer cell lines to identify proteins that might be important biomarkers of cancer. These proteins are often important in cancer development and the identification of such proteins is being used by collaborators to develop drugs to specifically act against these proteins to impede cancer growth. Further details on the structure of proteins identified as important to cancer are being determined using sequencing by capillary electrophoresis/TOF-mass spectrometry, where changes in sequence and posttranslational modifications can be determined. Tissue microarrays are being used to learn about the response of antibodies to these proteins in different tissue samples.
Ultimately, proteins identified as being important to a specific type of cancer are being developed into a protein chip format as a means for early diagnosis of cancer. Biostatistics are being used to determine which proteins are important in cancer transformation and how different cancers can be classified according to the protein expression of the cell.
Kan Zhu, Jia Zhao, David M. Lubman, Fred R. Miller, and Timothy J. Barder, "Protein PI Shifts Due To Post-Translational Modifications In The Separation And Characterization Of Proteins", Anal Chem, 2005, 77, 2745-2755.
Y. Wang, R. Wu, K.R. Cho, K.A. Shedden, T.J. Barder, D.M. Lubman, "Classification of Cancer Cell Lines using an Automated 2-D Liquid Mapping Method With Hierarchical Clustering Techniques", Molecular and Cellular Proteomics, Molecular and Cellular Proteomics,2006, 5(1), 43-52.
Manoj Pal, Allison Moffa, Arun Sreekumar, Stephen P. Ethier, Arul Chinnaiyan and David M. Lubman, "Differential Phosphoprotein Mapping in Cancer Cells Using Protein Microarrays Produced From 2-D Liquid Fractionation", Anal Chem, 2006, 78, 702-710
Jia Zhao, Kan Zhu, David M. Lubman, Fred R. Miller, and Timothy J. Barder, "Proteomic Analysis of Estrogen Response of Premalignant Human Breast Cells Using a 2-D Liquid Separations/Mapping Technique", Proteomics, 2006, 6, 3847-3861.
Jia Zhao, M.A. Anderson, D.M. Simeone, D.M. Lubman, "Protein Markers of Pancreatic Cancer in Human Serum Using Lectin Selected Sialic Acid Glycoproteins With Mass Spectrometric Analysis", Journal of Proteome Research, 2006, 5(7), 1792-1802.