TAp73 Inhibits EMT and Cell Migration in Pancreatic Cancer Cells through Promoting SMAD4 Expression and SMAD4-Dependent Inhibition of ERK Activation

Hendrik Ungefroren*, Björn Konukiewitz, Rüdiger Braun, Ulrich Friedrich Wellner, Hendrik Lehnert, Jens Uwe Marquardt

*Korrespondierende/r Autor/-in für diese Arbeit


Pancreatic ductal adenocarcinoma (PDAC) is a fatal disease due to early metastatic spread, late diagnosis and the lack of efficient therapies. A major driver of cancer progression and hurdle to successful treatment is transforming growth factor (TGF)-β. Recent data from pancreatic cancer mouse models showed that transcriptionally active p73 (TAp73), a p53 family member, inhibits tumor progression through promoting tumor suppressive canonical TGF-β/Smad signaling, while preventing non-canonical TGF-β signaling through extracellular signal-regulated kinases (ERK)1/2. Here, we studied whether this mechanism also operates in human PDAC. Using the PDAC-derived tumor cell lines PANC-1, HPAFII and L3.6pl, we showed that TAp73 induces the expression of the epithelial marker and invasion suppressor E-cadherin and the common-mediator Smad, SMAD4, while at the same time suppressing expression of the EMT master regulator SNAIL and basal and TGF-β1-induced activation of ERK1 and ERK2. Using dominant-negative and RNA interference-based inhibition of SMAD4 function, we went on to show that inhibition of ERK activation by TAp73 is mediated through SMAD4. Intriguingly, both SMAD4 and the α isoform of TAp73—but not the β isoform—interfered with cell migration, as shown by xCELLigence technology. Our findings highlighted the role of TAp73-SMAD4 signaling in tumor suppression of human PDAC and identified direct inhibition of basal and TGF-β-stimulated pro-invasive ERK activation as an underlying mechanism.

PublikationsstatusVeröffentlicht - 08.2023

Strategische Forschungsbereiche und Zentren

  • Profilbereich: Lübeck Integrated Oncology Network (LION)
  • Zentren: Universitäres Cancer Center Schleswig-Holstein (UCCSH)


  • 205-14 Hämatologie, Onkologie