Identification of distinctive protein expression patterns in colorectal adenoma.
OBJECTIVE
As a pre-malignant precursor, adenoma provides an ideal tissue for proteome profiling to investigate early colorectal cancer development and provide possible targets for preventive interventions. The aim of this study was to identify patterns of differential protein expression that distinguish colorectal adenoma from normal tissue.


METHODS
Twenty paired samples of adenoma and normal mucosa were analysed by 2-DE and MALDI-TOF/TOF MS to detect proteins with ≥2-fold differential expression.


RESULTS
Four proteins were up-regulated in adenoma (Annexin A3, S100A11, S100P and eIF5A-1) and three were down-regulated (Galectin-1, S100A9 and FABPL). S100P, galectin-1, S100A9 and FABPL expression was localised by immunohistochemistry.


CONCLUSIONS
Distinctive patterns of in vivo protein expression in colorectal adenoma were identified for the first time. These proteins have important functions in cell differentiation, proliferation and metabolism, and may play a crucial role in early colorectal carcinogenesis. The ability to recognise premalignant lesions may have important applications in cancer prevention.
Department of Colorectal Surgery, Concord Hospital and Discipline of Surgery, The University of Sydney, NSW Australia. lamfrancis@hotmail.com
Francis
F
F Lam
Lucy
L
Jankova
Owen F
OF
Dent
Mark P
MP
Molloy
Sun Young
SY
Kwun
Candice
C
Clarke
Pierre
P
Chapuis
Graham
G
Robertson
Philip
P
Beale
Stephen
S
Clarke
E Les
EL
Bokey
Charles
C
Chan
D000236:Adenoma / Q000235:genetics* / Q000378:metabolism* / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000595:Amino Acid Sequence; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000378:metabolism* / Q000473:pathology; D015180:Electrophoresis, Gel, Two-Dimensional; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D009092:Mucous Membrane / Q000166:cytology / Q000378:metabolism / Q000473:pathology; D020543:Proteome / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D040901:Proteomics / Q000379:methods*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D055815:Young Adult
D020543:Proteome