Loss of a Negative Feedback Loop Involving Pea3 and Cyclin D2 Is Required for Pea3-Induced Migration in Transformed Mammary Epithelial Cells

Abstract

The Ets family transcription factor Pea3 (ETV4) is involved in tumorigenesis especially during the metastatic process. Pea3 is known to induce migration and invasion in mammary epithelial cell model systems. However, the molecular pathways regulated by Pea3 are still misunderstood. In the current study, using in vivo and in vitro assays, Pea3 increased the morphogenetic and tumorigenic capacity of mammary epithelial cells by modulating their cell morphology, proliferation, and migration potential. In addition, Pea3 overexpression favored an epithelialmesenchymal transition (EMT) triggered by TGF-b1. During investigation for molecular events downstream of Pea3, Cyclin D2 (CCND2) was identified as a new Pea3 target gene involved in the control of cellular proliferation and migration, a finding that highlights a new negative regulatory loop between Pea3 and Cyclin D2. Furthermore, Cyclin D2 expression was lost during TGF-b1-induced EMT and Pea3-induced tumorigenesis. Finally, restored Cyclin D2 expression in Pea3-dependent mammary tumorigenic cells decreased cell migration in an opposite manner to Pea3. As such, these data demonstrate that loss of the negative feedback loop between Cyclin D2 and Pea3 contributes to Pea3-induced tumorigenesis.

CIC-DUX4 Induces Small Round Cell Sarcomas Distinct from Ewing Sarcoma

“…In mCDS, the top upregulated Cyclin D gene was Ccnd2 . A previous report showed that transcription of Ccnd2 is directly regulated by ETV4 (32), suggesting that Ccnd2 upregulation is achieved by multiple PEA3 family proteins induced by CIC-DUX4 in CDS. Therefore, the CCND2 can be used as an informative diagnostic tool, though CCND1 expression is also enhanced.…”

ETV transcriptional upregulation is more reliable than RNA sequencing algorithms and FISH in diagnosing round cell sarcomas with CIC gene rearrangements

“…Since the entire study cohort showed high ETV1/4/5 expression, we further evaluated the expression of downstream targets of ETV1/4/5 . Among them only SPRED2, NOTCH1 , and CCND2 were up‐regulated compared with other soft tissue tumors studied on the same RNAseq platform.…”

“…SPRED2 is a negative regulator of Ras/Raf‐1/ERK signaling pathway and is also up‐regulated in GIST, another tumor with high ETV1 expression. NOTCH1 and CCND2 were reported as downstream targets of ETV4 . NOTCH1 signaling pathway plays an important role in embryonic development, whereas CCND2 encodes cyclin D2 that controls cell cycle progression from G1 to S phase.…”

“…Expression levels of CIC, ETV1, ETV4, ETV5, and WT1 were evaluated on both RNAseq platforms in comparison to other soft tissue tumors in each platform. The mRNA expression of known PEA3 family downstream target genes, including SPRY2, SPRY4, SPRED2, GPR20, DUSP6 GBX2, FGF8, POU5F1, MMP1/2/3/7/9, TWIST1, SNAI1/2, PTGS2, BAX, CCND2, ZEB1, PTK2, PLAU, ICAM1, VEGFA, NOTCH1, NOTCH4, and SPP1 was investigated from the whole transcriptome sequencing platform, while FRG1, PITX1, ZSCAN4, RFPL2, TRIM43, and LEUTX, were evaluated as DUX4 targets …”

Protein deregulation associated with breast cancer metastasis

“…It is now generally believed that Pea3-induced tumorgenicity is mediated through the increased secretion of MMPs, such astromelysin-1 as well as type I and IV collagenases, although the precise mechanism is largely unknown [115,125]. Moreover, a novel functional role of Pea3 in tumorigenesis has recently been described, where it exerts a negative feedback loop to downregulate Cyclin D2 expression during TGF-b induced EMT, leading to increased cell migration [126]. Other proteins such as vimentin, intercellular adhesion molecule (ICAM-1) and cyclooxygenase 2, have also been reported to be upregulated by Pea3 [127][128][129].…”