Study On Srum Protein Fingerprint In Gastric Carcinoma Patients And Its Change Pre-and Post-Operation

Background Gastric carcinoma is one of the most common malignant tumor in our country and throughout the world. There are nearly200thousand new cancer cases happened in our country each year and still be me most commonly malignant tumor which account for17.2%of all new cancer cases. Although great process has been made in the treatment of gastric carcinoma, early diagnosis is about5%, which related to a survival rate of94%. Unfortunately, most diagnostic gastric carcinoma are advanced,5-year survival rates of the advanced gastric carcinoma persons is about30%. So in the clinical practice, we urgently need to establish a molecule index that is a simple, fast, and an adequacy sensitivity and specifility to judge life span of esophageal cancer, and to guide treatment. Objective We used a new proteomic technique-function magnetic bead, ANCHORCHIP technique, MALDI-TOF-MS, and ClinProTools to make up ClinProt system, to detect the spectrum of serum protein expression in gastric carcinoma patients, and established related serum protein diagnostic cast. We also detect the spectrum of serum protein expression in gastric carcinoma patients pro and after surgery, and retrieved the proteins that match with it as the expect proteins of gastric carcinoma in SWISS-PROT protein data base.MethodsPatients We retrospectively studied17gastric carcinoma patients, comparing with21normal persons.ClinProt system Composed of function magnetic bead、ANCHORCHIP technique、 MALDI-TOF-MS and ClinProTools bioinformatics method.Blood serum sample collection and disposal We collected empty stomach venous blood2ml in BD tube, stet one hour in room temperature(25℃), used clinic centrifuge10min at the speed of3OOOr/min to get serum,-80℃preserved. Standard serum quality control We used sigma blood serum to repeat the detection. One sigma standard serum was added into eight samples, the mean coefficients of variance(CV)for protein peak intensities were<30%.These confirmed this system has good repeatability.Apply ClinProTools (CPT) software to analysis the difference protein expression spectrum of gastric carcinoma We screened the expect protein peaks that have related to the onset of gastric carcinoma though analyzing difference protein peaks that had different M/Z in the data base.Use Protein data base internet to retrieve esophageal cancer related expect protein According to the M/Z of different protein peaks, we retrieved the proteins that highly expressed in serum of gastric carcinoma patients and significantly decreased after surgery in SWISS-PROT protein data base. The permissive error range of molecular weight is<0.5%.The main results1. Application of ClinProt system to analysis serum protein expression spectrum of the patientsWe collected the serum of gastric carcinoma patients and normal control, then used sigma blood serum to detect intercourse repeatability of every sample. The range of relative molecular mass was between800and10000. Compared with control group, gastric carcinoma group had11protein peaks (M/Z:M2822Da, M5341Da, M5910DaM7892Da, M2394Da、M4591Da、M4299Da、M8604Da、M8583Da、M1817Da、M2046Da)up-regulate, but5kinds protein peaks (M/Z:M4270Da、M6635Da、M8716Da、M3293Da, M1450Da3) down-regulate.The protein peaks (4299Da and5910Da) which had the strongest combination and subgroup ability were screened as category variable to establish category predictive model. Two group blood serum samples distributed in two ranges that had significance difference.2Application of ClinProt system to analysis the serum of gastric carcinoma patients pro and after surgery. We also detect the spectrum of serum protein expression in gastric carcinoma patients pre-and post-surgery. Comparing with serum after surgery, serum of pre-surgery patients had15protein peaks (M/Z:4699Da、6015Da、7910Da、7765Da、3934Da.8063Da、1411Da、5032Da、3773Da、6448Da、6610Da、9408Da、4395Da、3814Da、2820Da) up-regulate, but7kinds protein peaks (M/Z:M5808Da、4963Da、7779Da、3108Da.8604Da、9181Da、5446D)down-regulate.According to the M/Z of difference protein, we retrieved the proteins that match with it as the expect proteins of gastric carcinoma in SWISS-PROT protein data base. The permissive error range of molecular weight is<0.5%。Conclusions1.Magnetic bead based sample fractionation and MALDI-TOFMS as a tool to research protein expression map has repeatability and precision.2.11serum protein peaks are up-regulated, while5serum protein peaks are down-regulated in gastric carcinoma, these proteins maybe potential tumor markers of e gastric carcinoma.3. Using this technique we detected15serum protein peaks up-regulated in serums of pro-surgery patients and7protein peaks down-regulated in serums of after-surgery patients. Comparing with experimental group,we selected one proein and retrieved the protein that match with experiment one as the expect protein of gastric carcinoma in SWISS-PROT protein data base.