The NFKB-2 (Lyt-10) gene codes for an NF-kappa B-related transcription factor containing rel-polyG-ankyrin domains. Rearrangements of the NFKB-2 locus leading to the production of 3' truncated NFKB-2 proteins are recurrently found in lymphoid neoplasms, particularly cutaneous lymphomas, Such mutant NFKB-2 proteins have lost the ability to repress transcription that is typical of NFKB-2 subunit p52, and function as constitutive transcriptional activators. To verify whether the expression of abnormal NFKB-2 proteins can lead to malignant transformations in mammalian cells, we transfected human lymphoblastoid cell lines and murine fibroblasts (Balb/3T3) with expression vectors carrying the cDNAs coding far normal NFKB-2p52, Lyt-10C alpha or LB40 proteins, which are representative of the abnormal types found in lymphoma cases. The expression of both normal and mutant NFKB-2 proteins has a lethal effect on lymphoblastoid cells and a cytotoxic effect was also observed in murine fibroblasts. The fibroblast cell lines expressing Lyt-10C alpha or LB40, but not those expressing normal MFKB-2p52, were capable of forming colonies in soft agar. The analysis of individual clones revealed that cloning efficiency correlated with the expression levels of the abnormal proteins, Injection of the Lyt-10C alpha-transfected Balb cells in SCID mice led to tumor formation in all of the animals, whereas no tumors were observed in the mice injected with control or NFKB-2p52-transfected cells, thus indicating that abnormal NFKB-2 protein expression is tumorigenic in vivo. Our results show that mutant NFKB-2 proteins can lead to the transformed phenotype, and support the hypothesis that alterations in NFKB-2 genes may play a role in lymphomagenesis.
Constitutive expression of lymphoma-associated NFKB-2/Lyt-10 proteins is tumorigenic in murine fibroblasts / P. Ciana, A. Neri, C. Cappellini, F. Cavallo, M. Pomati, C. Chang, A. Maiolo, L. Lombardi. - In: ONCOGENE. - ISSN 0950-9232. - 14:15(1997), pp. 1805-1810.
|Titolo:||Constitutive expression of lymphoma-associated NFKB-2/Lyt-10 proteins is tumorigenic in murine fibroblasts|
CIANA, PAOLO (Primo)
NERI, ANTONINO (Secondo)
MAIOLO, ANNA TERESA (Penultimo)
|Parole Chiave:||NF-κB; NFKB-2; Transcription factor; Transformation|
|Settore Scientifico Disciplinare:||Settore BIO/14 - Farmacologia|
Settore BIO/18 - Genetica
|Data di pubblicazione:||1997|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1038/sj.onc.1201015|
|Appare nelle tipologie:||01 - Articolo su periodico|