Inducible expression of TGFβ, Snail and Zeb1 recapitulates EMT in vitro and in vivo in a NSCLC model

Abstract

The progression of cancer from non-metastatic to metastatic is the critical transition in the course of the disease. The epithelial to mesenchymal transition (EMT) is a mechanism by which tumor cells acquire characteristics that improve metastatic efficiency. Targeting EMT processes in patients is therefore a potential strategy to block the transition to metastatic cancer and improve patient outcome. To develop models of EMT applicable to in vitro and in vivo settings, we engineered NCI-H358 non-small cell lung carcinoma cells to inducibly express three well-established drivers of EMT: activated transforming growth factor β (aTGFβ), Snail or Zeb1. We characterized the morphological, molecular and phenotypic changes induced by each of the drivers and compared the different end-states of EMT between the models. Both in vitro and in vivo, induction of the transgenes Snail and Zeb1 resulted in downregulation of epithelial markers and upregulation of mesenchymal markers, and reduced the ability of the cells to proliferate. Induced autocrine expression of aTGFβ caused marker and phenotypic changes consistent with EMT, a modest effect on growth rate, and a shift to a more invasive phenotype. In vivo, this manifested as tumor cell infiltration of the surrounding mouse stromal tissue. Overall, Snail and Zeb1 were sufficient to induce EMT in the cells, but aTGFβ induced a more complex EMT, in which changes in extracellular matrix remodeling components were pronounced.

Involvement of ZEB1 and Snail1 in excessive production of extracellular matrix in Fuchs endothelial corneal dystrophy

“…33 Furthermore, with regard to the Figure 6 The effect of inhibiting TGFβ signaling pathway on suppressing ZEB1 and Snail1 gene expression, as well as on the production of ECM in iFECD. (a-f) iHCEC and iFECD were cultured with SB431542 (1, 3, and 10 μM) for 24 h. Expression mRNA of ZEB1, SNAI1, COL1A1, FN1, and COL4A1 was evaluated using real-time PCR.…”

Evolutionary functional analysis and molecular regulation of the ZEB transcription factors

“…ZEB induction under the influence of TGF-beta stimulation can be an early or late event. For instance, ZEB1 upregulation can be observed in HMEC cells within 6 h of treatment, while in NSCLC cells ZEB1 can only be detected after 7 days of TGF stimulation [91,96]. The fact that EMT-related effects can already be observed after 4 days of TGF-b stimulation in the case of NSCLC cells suggests that for instance Snail and TWIST are the initial EMT drivers.…”

Epithelial-to-mesenchymal transition confers pericyte properties on cancer cells

“…Ectopic induction of EMT fails to induce evident metastasis in transplantation and transgenic mouse tumor models (13,14). Acquisition of mesenchymal traits by carcinoma cells may not facilitate metastasis (11).…”