THE NF-KAPPA-B TRANSCRIPTION FACTOR AND CANCER - HIGH EXPRESSION OF NF-KAPPA-B- AND I-KAPPA-B-RELATED PROTEINS IN TUMOR-CELL LINES

NF-kappa B is a pleiotropic transcription factor which controls the ex pression of many genes and viruses. To date, there is good evidence, b ut no difinitive proof, for its role in tumor formation and developmen t of metastasis. To investigate the possibility that members of the NF -kappa B family could participate in the molecular control of the tran sformed and invasive phenotype, we examined the expression of these pr oteins in a variety of human tumor cell lines. The expression of p50, p65, p52 and I kappa B was quantified at the protein level using weste rn immunoblot and mobility shift assay and at the RNA level by norther n blot. We observed high expression of the NF-kappa B inhibitor I kapp a B in the ovarian carcinoma cell line OVCAR-3 together with constitut ive nuclear NF-kappa B activity. We also studied the colon carcinoma c ell line HT-29 and its metastatic counterpart HTM-29 and we observed s pecific expression of the p52 NF-kappa B-related protein in the metast atic cells. Our data confirm that NF-kappa B could be involved in the genesis of a variety of cancers including solid tumors and provide us with interesting models to explore the exact role of these transcripti on factors in cancer.