[EGFR protein is a negative prognostic and predictive factor in wild-type RAS colorectal cancer]. / Az EGFR-protein-expresszió negatív prognosztikus és prediktív marker vad RAS típusú vastagbélrákban.

Negative predictive markers of the anti-EGFR antibody therapies are RAS or BRAF mutations, while left sidedness can be considered as a positive predictor. Here we analyzed 97 wild type RAS metastatic colorectal cancers looking for the prognostic and predictive roles of EGFR protein expression. We found that right-sided colorectal cancers are characterized by significantly higher EGFR protein expression as compared to left-sided ones, irrespective of the primary or metastatic tissue analysis. Furthermore, tumors with multiple organ involvement are characterized by significantly higher EGFR protein expression as compared to single organ ones. In the homogenous cetuximab treated cohort (n=90) we have found that lower than the applied EGFR protein expression cut-off was associated with favorable survival. In the multivariate analysis only sidedness proved to be a strong independent predictor, however sidedness is an EGFR-dependent predictor of anti-EGFR therapy.

EGFR Protein Expression in KRAS Wild-Type Metastatic Colorectal Cancer Is Another Negative Predictive Factor of the Cetuximab Therapy.

The selection of colorectal cancer patients for anti-epidermal growth factor receptor (EGFR) antibody therapy is based on the determination of their RAS mutation status-a strongly negative predictive factor-since the protein target, EGFR, is not a reliable predictor of therapeutic response. In this study, we revisited the EGFR protein issue using a cohort of 90 patients with KRAS exon2 wild-type colorectal cancer who have been treated with cetuximab therapy. Twenty-nine of these patients had metastatic tissue available for analysis. The level of EGFR protein expression in the patients was determined by immunohistochemistry and evaluated by H-score (HS) methodology. Progression-free survival (PFS) and overall survival (OS) of the patients were determined according to the EGFR-HS ranges of both the primary and metastatic tissues using Kaplan-Meyer statistics. In the case of primary tumors, EGFR scores lower than HS = 200 were associated with significantly longer OS. In the case of metastatic tissues, all levels lower than the EGFR-HS range chosen were associated with significantly longer OS. These results are explained by the fact that metastatic tissues rarely maintained the expression levels of the primary tumors. On the other hand, high EGFR expression levels in either primary tumors or metastatic tissues were associated with multiple metastatic disease. This suggests a negative prognostic role of EGFR expression. However, in a multivariate analysis, one-sidedness remained a strong independent predictive factor of survival. Previous studies demonstrated that the EGFR expression level depends on sidedness. Therefore, a subgroup analysis of the left- and right-sided cases was performed on both primary and metastatic tissues. In the case of metastic tissues, an analysis confirmed a better OS in low EGFR protein-expressing cases than in high EGFR protein-expressing cases. Collectively, these data suggest that EGFR protein expression is another negative predictive factor of the efficacy of cetuximab therapy of KRAS exon2 wild-type colorectal cancer.

Expression of tumor necrosis factor (TNF)-alpha protein in the subcutaneous and visceral adipose tissue in correlation with adipocyte cell volume, serum TNF-alpha, soluble serum TNF-receptor-2 concentrations and C-peptide level.

OBJECTIVE: The aim of the study was to evaluate the expression of tumor necrosis factor (TNF)-alpha protein in the subcutaneous and visceral adipose tIssue in correlation with adipocyte cell Volume, serum TNF-alpha, soluble TNF-receptor-2 (sTNFR-2) and indirect parameters of insulin resistance in overweight/obese and lean healthy persons. DESIGN: A cross-sectional case-control study was used. PATIENTS: Twenty-eight overweight/obese probands with normal glucose tolerance (BMI>27 kg/m(2)) and 15 lean people (BMI<25 kg/m(2)), all of them undergoing planned surgical operation, participated in the study. METHODS: Two to four grams of subcutaneous and visceral adipose tIssue were removed and studied using semi-quantitative immunohistochemical staining of the TNF-alpha protein. Serum TNF-alpha, sTNFR-2 (ELISA) and fasting C-peptide (RIA) were measured. RESULTS: TNF-alpha protein was expressed in adipocytes of both depots. The expression was evaluated visually and found to be greater in the obese patients. Significantly higher serum TNF-alpha (5.58+/-0.87 pg/ml vs 4.21+/-0.55, mean+/-s.d., P<0.01, Mann-Whitney) and sTNFR-2 levels (7.84+/-3.56 ng/ml vs 4.59+/-1.35, P=0.005) were found in the obese subgroup in correlation with the fasting C-peptide level (r=0.49, P=0.003; and r=0.74, P=0.001) and the C-peptide/ blood glucose ratio (r=0.47, Spearman, P=0.005; and r=0.70, P=0.001). The cell Volume of both adipocyte depots was found to have a significant positive correlation with serum TNF-alpha and sTNFR-2 levels in the total group of patients (subcutaneous: r=0.52, P=0.0003; r=0.69, P<0.0001; visceral: r=0.65, P<0.0001; r=0.63, P<0.0001) and in both subgroups. CONCLUSIONS: Adipocyte cell Volume of both the subcutaneous and visceral fat depots may be determinants of TNF-alpha, sTNFR-2 production and obesity-linked insulin resistance.