H19 mRNA-like noncoding RNA promotes breast cancer cell proliferation through positive control by E2F1.
The imprinted H19 gene has riboregulatory functions. We show here that H19 transcription is up-regulated during the S-phase of growth-stimulated cells and that the H19 promoter is activated by E2F1 in breast cancer cells. H19 repression by pRb and E2F6 confirms the E2F1-dependent control of the H19 promoter. Consistently, we demonstrate by chromatin immunoprecipitation assays that endogenous E2F1 is recruited to the H19 promoter in vivo. The functionality of E2F promoter sites was further confirmed by gel shift and mutagenesis experiments, revealing that these sites are required for binding and promoter response to E2F1 exogenous expression and serum stimulation. Furthermore, we show that H19 overexpression confers a growth advantage on breast cancer cells released from growth arrest as well as in asynchronously growing cells. The H19 knockdown by small interfering RNA duplexes impedes S-phase entry in both wild-type and stably H19-transfected cells. Based on these findings, we conclude that the H19 RNA is actively linked to E2F1 to promote cell cycle progression of breast cancer cells. This clearly supports the H19 oncogenic function in breast tumor genesis.
ERI-8 INSERM Signalisation des Facteurs de Croissance dans le Cancer du Sein, Protéomique Fonctionnelle, UPRES-EA 1033, IFR 118, Université des Sciences et Technologies de Lille (USTL), Villeneuve d'Ascq, France.
Nathalie
N
Berteaux
Séverine
S
Lottin
Didier
D
Monté
Sébastien
S
Pinte
Brigitte
B
Quatannens
Jean
J
Coll
Hubert
H
Hondermarck
Jean-Jacques
JJ
Curgy
Thierry
T
Dugimont
Eric
E
Adriaenssens
D001483:Base Sequence; D001943:Breast Neoplasms / Q000209:etiology / Q000473:pathology*; D018797:Cell Cycle Proteins / Q000502:physiology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D004268:DNA-Binding Proteins / Q000502:physiology*; D050684:E2F Transcription Factors; D050687:E2F1 Transcription Factor; D050701:E2F6 Transcription Factor; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D062085:RNA, Long Noncoding; D022661:RNA, Untranslated / Q000502:physiology*; D016196:S Phase; D014157:Transcription Factors / Q000502:physiology*
D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D050684:E2F Transcription Factors; D050687:E2F1 Transcription Factor; C493753:E2F1 protein, human; D050701:E2F6 Transcription Factor; C094335:H19 long non-coding RNA; D062085:RNA, Long Noncoding; D022661:RNA, Untranslated; D014157:Transcription Factors