| Hepatocellular carcinoma (HCC) is a malignant tumor responsible for approximately 600,000-700,000 deaths worldwide, and is becoming more prevalent not only in South-East Asia and Africa but also in western countries. Due to high infection rates with hepatitis B virus (HBV),55% new cases occur in China every year. The carcinogenesis risk for HBV carriers is about 200 times higher than that for non-carriers. Despite improvements in surveillance and clinical treatment strategies, the prognosis of HCC still remains dismal. Liver transplantation (LT) has come to play an important role in its management. However the scarceness of liver donors limited its clinical application. Therefore, risk estimation of postsurgical tumor recurrence is an essential element in selecting patients with HCC for LT.Hepatocarcinogenesis is a process characterized by accumulation of genetic alternation including chromosomal rearrangements, activation of oncogenes, and inactivation of tumor suppressor genes. Our previous study has shown that genes favoring HCC metastasis progression are initiated relatively early in the primary tumors.These findings propel us to investigate the tumor genetic changes associated with HCC metastasis which could be of great value in predicting prognosis and subsequent treatment. microarray-based high-density singlenucleotide polymorphism (SNP) analysis makes a reproducible and rapid determination of genome-wide alterations possible. However, DNA extracted from tumor tissue can only be obtained after resection, which made its clinical application limited.It has been verified that Tumor-derived DNA can be detected in the plasma or serum of cancer patients. A recent published paper showed circulating DNA from tumor patients can be used to track disease. Thus, it may be a good target to study instead of tumor tissues DNA for its easy accessibility, simple manipulation, and prognostic information available before operation. Single nucleotide polymorphisms (SNPs) are the most common genetic variation in the human genome, As genetic markers, SNPs have several advantages over microsatellites sequence repeats, including abundance (one every 750-1000 bp) stability, and suitability for high throughput analysis. Literature report documented that some SNPs present different allele frequencies between tumor and normal tissues. Therefore, studies on SNPs genotyped from tumor DNA may lead to fundamental insights into the biological importance of genetic variations in the tumor genome. In the current study, we use oligonucleotide arrays and high-throughput mass spectrometry to detect plasma circulating DNA for genetic variation associated with poor prognosis in HBV-related HCC patients after LT.Purpose:To explore the genetic alternation associated with recurrence and metastisis in tumor genome of HCC patients who underwent liver transplantation using SNP microarrays.Method:We devide all the patients who passed enter criteria into two groups (recurrence group and non-recurrence group). Thirty tumor FFPE samples randomly selected from recurrence group and non-recurrence group were acquired. Tumor cells were manually microdissected from 3 consecutive sections(10μm) under a dissecting microscope. Tumor DNA were extracted using QIAamp DNA FFPE Tissue Kit. Mapping PCR test was used as a quality control of FFPE DNA. All the samples passed quality control were amplified and then hybridized on Affymetrix SNP 6.0. genotype were analysised by Genotyping Console 3.0.1. Cochran-Armitage trend test were used to calculate the different alleles distribution between recurrent patients and non-recurrent patients, Cluster software (version 3.0) and TreeView software (version 1.0.13) were used to illustrate the characteristic of the two groups.Results:We found 1272 SNPs exhibiting differenct genotype distribution between recurrence group and non-recurrence group (p<0.01). Among these SNPs there were 30 SNPs have p value less than 0.001. When perform claster analysis using these SNPs, we found all the patients were divided into two groups (high risk group and low risk group). And when we perform survival analysis using Kaplane-Meier method, we found low risk group have higher survival rate than high risk group (p<0.001).Conclusion:Tumor recurrence after liver transplantation may be related with tumor genome characteristic. Certain SNPs may be potential bio-marks of tumor recurrence after liver transplantation for HCC patients.Purpose:To further evaluate the relationship between tumor recurrence and selected SNPs that genotyped in plasma circulating DNA using large sample set.Methods:A total of 102 cases of HCC patients who underwent liver transplantation were enrolled in this sutdy. Circulating DNA were extracted from plasma samples which obtained before operation. Selected SNPs were genotyped using MassARRAY system (Sequenom) by means of matrix assisted laser desorption ionisation-time of flight mass spectrometry method (MALDI-TOF). Genotype calling was performed in real time with MassARRAY RT software version 3.0.0.4 and analyzed using the MassARRAY Typer software version 3.4 (Sequenom). Haploview 4.0 was used to evaluate the prognostic aspect of each SNP, and the results were validated by another independent sample set (47cases).Results:Minor allele at rs894151 and rs12438080 genotyped in circulating DNA displayed dose-response associations with recurrence and metastasis in HBV-related HCC patients after LT. Univariate analysis showed rs894151 and rs12438080 were prognostic factors to relapse-free survival (p=0.007 and p=0.003, respectively). Multivariate analyses demonstrated that the co-index (rs894151/rs12438080) was an independent prognostic factor for relapse-free survival (p=0.030). In patients exceeding Milan criteria, the co-index was an independent prognostic factor of recurrence (p=0.004).Conclusion:The co-index of rs894151 and rs12438080 is a promising predictor of recurrence and metastasis in HBV-related HCC patients who underwent LT especially for those exceeding Milan criteria.
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