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Specific HPV DNA sequences are associated with more than 90% of invasive carcinomas of the uterine cervix. Viral E6 and E7 oncogenes are key mediators in cell transformation by disrupting TP53 and RB pathways. To investigate molecular mechanisms involved in the progression of invasive cervical carcinoma, we performed a gene expression study on cases selected according to viral and clinical parameters. Using Coupled Two-Way Clustering and Sorting Points Into Neighbourhoods methods, we identified a 'cervical cancer proliferation cluster' composed of 163 highly correlated transcripts. Most of these transcripts corresponded to E2F pathway genes controlling cell division or proliferation, whereas none was known as TP53 primary target. The average expression level of the genes of this cluster was higher in tumours with an early relapse than in tumours with a favourable course (P = 0.026). Moreover, we found that E6/E7 mRNA expression level was positively correlated with the expression level of the cluster genes and with viral DNA load. These findings suggest that HPV E6/E7 expression level plays a key role in the progression of invasive carcinoma of the uterine cervix via the deregulation of cellular genes controlling tumour cell proliferation. HPV expression level may thus provide a biological marker useful for prognosis assessment and specific therapy of the disease.

TCF1: (transcription factor 1) encoding hepatocyte nuclear factor 1alpha (HNF1alpha) is mutated in 50% of liver cell adenomas, a benign tumor closely associated with oral contraceptive use. These genetic alterations inactivate both alleles, leading to the absence of wild-type HNF1alpha expression in liver cell adenomas. To search for a role of HNF1alpha in other hormone-related neoplasias, we screened for HNF1alpha mutations in a series of 36 endometrial carcinomas, 29 breast carcinomas and 20 ovarian epithelial tumors. HNF1alpha mutations were identified in 4/36 (11%) of endometrial tumors. No mutation was found in ovarian and breast tumors. HNF1alpha mutations were somatic in all cases, monoallelic in three cases and biallelic in one case. These results suggest that HNF1alpha may contribute to endometrial carcinogenesis through complete HNF1alpha inactivation like in liver cell adenoma or by haploinsufficiency like in MSI-H colorectal cancer.