Liver Metastases Of Colorectal Cancer And Its Significance In Differential Expression Of Proteins

Objective: Using surface-enhanced laser desorption/ionization time-of-flight massspectrometry protein chip (SELDI-TOF-MS) joint laser capture microdissection (LCM)technology to screen colorectal cancer and liver metastases marker protein, explorespecific markers of colorectal cancer, provide help for colorectal cancer and livermetastasis of early diagnosis, prognosis and treatment. Methods: Acquisition normalcolorectal cells, primary focal cells and liver metastases cells from24colorectal cancerpatients with liver metastases; to apply SELDI-TOF-MS technology to spectrum analysisof protein which we acquired; using Biomarker Wizard software analysis differentiallyexpressed proteins; to identify a specific molecular weight protein corresponding to themarker proteins by querying the database. Selecting two of the significant proteinsS100A11and Raf kinase inhibitor protein(RKIP) were verified by ELISA and IHC.Results: Compared the SELDI mass spectra of normal colon, colorectal cancer primarytumors and colorectal liver metastases3groups cells and found that between the twogroups of colorectal cancer primary tumors and normal colon there are15marker proteins,12were up-regulated and3were down-regulated; between the two groups of colorectalliver metastases and primary tumor exist9marker proteins,5were up-regulated,4weredown-regulated.4676.63Da,11740.87Da,21063.59Da and22783.36Da protein peakshave the most obvious difference(P<0.01).To identify a specific molecular weight proteincorresponding to the marker proteins as Apoptosis regulator Bax-γ, Protein S100A11, Rafkinase inhibitor protein(RKIP) and Heat shock protein27(HSP-27) by querying theExPasy database.The expression of Protein S100A11and HSP-27were up-regulated,Apoptosis regulator Bax-γ and RKIP were down-regulated.The ELISA and IHCverification results of S100A11and RKIP consistent with MS. Conclusion: SELDI protein chip technology combined with LCM may filter out the high sensitive and specificmarker proteins of colorectal cancer, detected different proteins S100A11and RKIP maybe biomarkers of specific in liver metastases of colorectal cancer.