ING4 regulates a secretory phenotype in primary fibroblasts with dual effects on cell proliferation and tumor growth

ABSTRACT: ING proteins play an essential role in the control of a variety of cellular functions whose deregulation is associated with tumor formation and dissemination, such as proliferation, apoptosis, senescence or invasion. Accordingly, loss of function of ING proteins is a frequent event in many types of human tumors. In this report, we have studied the function of ING4, a member of the ING family of tumor suppressors, in the context of normal, non-transformed primary fibroblasts. We show that ING4 negatively regulates cell proliferation in this cell type. The antiproliferative action of ING4 requires its ability to recognize chromatin marks, it is p53-dependent and it is lost in an ING4 cancer-associated mutant. Gene expression analysis shows that ING4 regulates the expression and release of soluble factors of the chemokine family. The secretory phenotype regulated by ING4 in primary fibroblasts displays a selective paracrine effect on proliferation, fostering the division of tumor cells, while inhibiting division in primary fibroblasts. Consistently, ING4-expressing fibroblasts promoted tumor growth in vivo in co-injection tumorigenesis assays. Collectively, our results show that ING4 not only can regulate the proliferation of primary non-transformed human fibroblasts, but also orchestrates a secretory phenotype in these cells that promotes tumor cell proliferation in vitro and in vivo. These findings support a critical role for ING4 expression in normal cells in the non-cell autonomous regulation of tumor growth. Gene expression analysis shows that ING4 regulates the expression and release of soluble factors of the chemokine family. Two independent retroviral infections were performed in early pasaje IMR-90 fibroblasts with wild-type ING4 wild type and the N214D mutant. All of them were hibridazed by duplicate againts a reference sample from vector-infected cells

ORGANISM(S): Homo sapiens

SUBMITTER: Gema Moreno-Bueno 

PROVIDER: E-GEOD-42412 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress