Highly specific marker genes for detecting minimal gastric cancer cells in cytology negative peritoneal washings
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
Authors: Mori, K; Aoyagi, K; Ueda, T; Danjoh, I; Tsubosa, Y; Yanagihara, K; Matsuno, Y; Sasako, M; Sakamoto, H; Mafune, K; Kaminishi, M; Yoshida, T; Terada, M; Sasaki, H
Peritoneal wash cytology plays a pivotal role in the decision for gastric cancer treatment because advanced gastric cancer often turns out incurable with peritoneal metastasis. Molecular detection of minimal cancer cells from peritonea] washings may overcome the sensitivity boundary of conventional cytology and contribute to the prediction of the disease outcome. To select marker candidates out of ten thousands of genes, we performed microarray analyses in 12 gastric cell lines and 8 peritonea] washings of early stage cases. With 40 candidates selected by the above expression profiling, RT-PCR in 16 representative peritoneal wash samples was performed to identify genes specific to cytology positive samples. The finally selected five genes, CK20, FABP1, MUC2, TFF1, and TFF2, were then evaluated for their utility as a marker for minimal residual disease in 99 peritoneal wash samples. Nested RTPCR using the five genes showed positive results highly specific to incurable cases (91-100%). With a high specificity, the combination of these five genes succeeded in identifying 6 out of 20 (30%) additional patients with all types of early recurrence that could not be predicted by the conventional method. The six newly identified recurrences included four non-peritoneal ones, showing that RT-PCR using the five genes without a real-time quantitative PCR technique contributes to the detection of minimal residual disease. (C) 2003 Elsevier Inc. All rights reserved.
Hepatocellular adenoma subtype classification using molecular markers and lmmunohistochemistry
Authors: Bioulac-Sage, Paulette; Rebouissou, Sandra; Thomas, Cristel; Blanc, Jean-Frederic; Saric, Jean; Cunha, Antonio Sa; Ruiller, Anne; Cubel, Gaeelle; Couchy, Gabrielle; Imbeaud, Sandrine; Balabaud, Charles; Zucman-Rossi, Jessica
Hepatocellular adenomas (HCA) with activated P-catenin present a high risk of malignant transformation. To permit robust routine diagnosis to allow for HCA subtype classification, we searched new useful markers. We analyzed the expression of candidate genes by quantitative reverse transcription polymerase chain reaction QRT-PCR followed by inummohistochemistry to validate their specificity and sensitivity according to hepatocyte nuclear factor 1 alpha HNF1 alpha a) and P-catenin mutations as well as inflammatory phenotype. Quantitative RT-PCR showed that FABP1 (liver fatty acid binding protein) and UGT2B7were downregulated in HNF1 alpha-inactivated HCA (P <= 0.0002); GLUT (glutamine synthetase) and GPR49 overexpression. were associated with beta-catenin-activating mutations (P <= 0.0005), and SAA2 (serum amyloid A2) and CRP (C-reactive protein) were upregulated in inflammatory HCA (P = 0.0001). Inummohistochemistry validation confirmed that the absence of liver-fatty acid binding protein (L-FABP) expression rightly indicated HNF1 alpha mutation (100% sensitivity and specificity), the combination of glutamine synthetase overexpression and nuclear P-catenin staining were excellent predictors of beta-catenin-activating mutation (85% sensitivity, 100% specificity), and SAA hepatocytic staining was ideal to classify inflammatory HCA (91% sensitivity and specificity). Finally, a series of 93 HCA was unambiguously classified using our 4 validated inummohistochemical markers. Importantly, new associations were revealed for inflammatory HCA defined by SAA staining with frequent hemorrhages (P = 0.003), telangiectatic phenotype (P < 0.001), high body mass index, and alcohol intake (P <= 0.04). Previously described associations were confirmed and in particular the significant association between beta-catenin-activated HCA and hepatocellular carcinomas (HCC) at diagnosis or during follow-up (P < 10(-5)). Conclusion: We refined HCA classification and its phenotypic correlations, providing a routine test to classify hepatocellular adenomas using simple and robust inummohistochemistry.