Proteomic analysis reveals novel proteins associated with progression and differentiation of colorectal carcinoma

The objective of this study is to characterize differential proteomic expression among well-differentiation and poor-differentiation colorectal carcinoma tissues and normal mucous epithelium.

The study is based on quantitative 2-dimensional gel electrophoresis and analyzed by PDquest.

Excluding redundancies due to proteolysis and posttranslational modified isoforms of over 600 protein spots, 11 proteins were revealed as regulated with statistical variance being within the 95th confidence level and were identified by peptide mass fingerprinting in matrix assisted laser desorption/ionization time-of-flight mass spectrometry. Progression-associated proteins belong to the functional complexes of tumorigenesis, proliferation, differentiation, metabolism, and the regulation of major histocompatibility complex processing and other functions. Partial but significant overlap was revealed with previous proteomics and transcriptomics studies in CRC. Among various differentiation stage of CRC tissues, we identified calreticulin precursor, MHC class I antigen (human leukocyte antigen A ), glutathione S-transferase pi1, keratin 8, heat shock protein 27, tubulin beta chain, triosephosphate, fatty acid-binding protein, hemoglobin (deoxy) mutant with val b 1 replaced by met (HBB), and zinc finger protein 312 (FEZF2).

Their functional networks were analyzed by Ingenuity systems Ingenuity Pathways Analysis and revealed the potential roles as novel biomarkers for progression in various differentiation stages of CRC.