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Some host-related factors may predict the risk of metastasis after surgery of colorectal cancer (CRC). The endothelial adhesion molecule E-selectin is implicated in the metastatic spread of CRC. We postulated that some polymorphisms within the E-selectin gene, especially the S128R polymorphism, may increase the risk of metastases by facilitating adhesion of tumour cells to the endothelium. We collected blood samples for DNA extraction from 264 patients treated for stage II or III CRC and from 310 healthy controls in order to assess three polymorphisms within the E-selectin gene (S128R, G98T and L554F) and one within the P-selectin gene (V640L). Genotypes were analysed by the allelic discrimination TaqMan real-time PCR assay. The S128R polymorphism was detected in 59 patients (22.3%) and was strictly correlated with the G98T polymorphism. In multivariate analysis, the S128R polymorphism was associated with shorter event-free survival (EFS) and overall survival (OS) in the whole population (EFS: P=.003, HR 1.82, 95% CI 1.23-2.70; OS: P<10(-4), HR 4.31, 95% CI 2.46-10.99), in patients with stage II CRC(EFS: P=.04, HR 1.92, 95% CI 1.02-3.60; OS: P=.02, HR 4.44, 95% CI 1.16-17.03), and in patients with stage III CRC (EFS: P=.04, HR 1.68, 95% CI 1.01-2.80; OS: P=.001, HR 4.04, 95% CI 1.73-9.46). L554F and V640L polymorphisms had no prognostic value. The S128R polymorphism is a constitutional factor associated with a higher risk of relapse and death in patients treated for CRC. This polymorphism detection may permit better selection of patients suitable for adjuvant therapy, especially among those with stage II disease.

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) has been widely used as a control RNA in Northern blotting and in reverse transcriptase-polymerase chain reaction (RT-PCR) analyses. We investigated the expression of GAPDH in a large series of primary breast cancers and in MCF7 human mammary epithelial breast cancer cells treated with oestradiol. The expression of GAPDH was quantified by a real-time one-step RT-PCR assay, based upon the 5' nuclease activity of Taq polymerase using an Abi Prism 7700 Sequence Detector System (Perkin Elmer, France). Using the Spearman test, GAPDH expression was found to correlate inversely with the age of the patients at diagnosis (P = 0.003; r = -0.147), oestradiol receptors (ER) (P<0.0001; r = -0.327) and progesterone receptors (PgR) (P < 0.0001; r = -0.206). A positive correlation was observed between GAPDH expression and the histo-prognostic grading (HPG) (P < 0.0001; r = 0.344). Moreover, the overall survival (OS) and the relapse-free survival (RFS) were significantly reduced in patients whose tumours showed an enhanced level of GAPDH expression (OS, P = 0.046; RFS, P = 0.021). Multivariate analyses demonstrated that GAPDH was not an independent prognostic factor. Finally, in MCF7 cells treated with oestradiol. a statistically significant dose-dependent increase in GAPDH expression was observed. These results show that GAPDH expression is associated with breast cancer cell proliferation and with the aggressiveness of tumours. The present study demonstrates that, in cancer, the use of GAPDH gene expression should not be used as a control RNA.

We reveiwed the relationships between ERBB2 amplification and/or overexpression in human breast cancer and the clinicopathological parameters described in the literature (97 studies involving 22,616 patients) in order to draw conclusions regarding its clinical interest. The mean of ERBB2 positivity (26%, ranging from 5 to 55%) is not dependent on the method used to evaluate ERBB2 amplification or overexpression. Despite the discrepancies observed between the different studies, several associations between ERBB2 positivity and the classical clinicopathological parameters were noted. There are clear relationships between ERBB2 positivity and the lack of steroid receptors, the histological subtypes of mammary tumours (ductal invasive and in situ), worse histological and nuclear grades, aneuploidy and high rate of proliferation. In univariate analyses, ERBB2 is strongly associated with poor prognosis. All these data indicate that ERBB2 is a marker of aggressiveness of the tumour. However, ERBB2 does not retain a clinical prognostic significance in multivariate analyses, since it is associated with several strong prognostic parameters. When considering the prognostic value of ERBB2 in relation to treatment, a significantly worse survival of the treated patients is noted in ERBB2 positive patients. This suggest that ERBB2 could be a marker of reduced response to chemotherapy and hormonal treatment. With respect to the tumour response to treatment, the results, provided as yet by pilot studies, remain controversial and further investigations are necessary to evaluate the predictive value of ERBB2. Finally, new therapeutic approaches targeting the cells overexpressing ERBB2 have been developed.