Epithelial to mesenchymal transition influences fibroblast phenotype in colorectal cancer by altering miR‐200 levels in extracellular vesicles

Abstract

Colorectal cancer (CRC) with a mesenchymal gene expression signature has the greatest propensity for distant metastasis and is characterised by the accumulation of cancer‐associated fibroblasts in the stroma. We investigated whether the epithelial to mesenchymal transition status of CRC cells influences fibroblast phenotype, with a focus on the transfer of extracellular vesicles (EVs), as a controlled means of cell–cell communication. Epithelial CRC EVs suppressed TGF‐β‐driven myofibroblast differentiation, whereas mesenchymal CRC EVs did not. This was driven by miR‐200 (miR‐200a/b/c, ‐141), which was enriched in epithelial CRC EVs and transferred to recipient fibroblasts. Ectopic miR‐200 expression or ZEB1 knockdown, in fibroblasts, similarly suppressed myofibroblast differentiation. Supporting these findings, there was a strong negative correlation between miR‐200 and myofibroblastic markers in a cohort of CRC patients in the TCGA dataset. This was replicated in mice, by co‐injecting epithelial or mesenchymal CRC cells with fibroblasts and analysing stromal markers of myofibroblastic phenotype. Fibroblasts from epithelial tumours contained more miR‐200 and expressed less ACTA2 and FN1 than those from mesenchymal tumours. As such, these data provide a new mechanism for the development of fibroblast heterogeneity in CRC, through EV‐mediated transfer of miRNAs, and provide an explanation as to why CRC tumours with greater metastatic potential are CAF rich.

Targetable fibroblast phenotypes and EMT malignant cell states cooperate to promote tumor progression in esophageal adenocarcinoma

“…2G). In keeping with the mechanism described by Bhome et al (5), ZEB1 and ZEB2 (inducers of EMT; ZEB2 not shown), Vimentin (Vim), Cadherin 11 (CHD11) and a-SMA (ACTA2) were preferentially expressed in a small subset of cancer cell transcriptomes from patients de ned as having an active EMT1-EMT2-Epi expression program (Fig. 2H).…”

“…We have shown that the tumor-promoting and chemoprotective properties of CAFs are associated with an activated myo broblast (a-Smooth Muscle Actin/ACTA2 + ) phenotype that can be reversed with Phosphodiesterase type 5 inhibitors (PDE5i) (4). Recently, our colleagues provided a new mechanism for generating broblast heterogeneity, via the differential extracellular-vesicle (EV) transfer of miRNA, dependent on the epithelial or mesenchymal phenotype of the cancer, where mesenchymal colorectal cancer EVs (depleted for miR-200) did not suppress TGF-b-driven myo broblast differentiation (5). The actin cytoskeleton promotes myo broblast function during brogenesis and in tumor stroma remodeling (6).…”

Intercellular crosstalk between cancer cells and cancer-associated fibroblasts via extracellular vesicles

“… [ 181 ] miR-200 family Colorectal cancer CRC cells with an epithelial phenotype but not a mesenchymal phenotype secrete miR-200 family members via EVs to attenuate TGF-β-mediated CAF features by targeting ZEB1 in normal fibroblasts. [ 45 ] miR-4534 Colorectal cancer Suppress autophagy to induce CAF phenotypes in fibroblasts. EV miR-4534 targets ATG2B expression.…”

“…Given that aberrant p53 function can confer a CAF phenotype on fibroblasts [ 38 , 39 , 44 ], the expression status of the TP53 gene in both cancer cells and CAFs may reflect the features of CAF subtypes. Recently, Bhome et al demonstrated that the EMT phenotype of colorectal cancer (CRC) cells influences CAF generation [ 45 ] CRC cells with an epithelial phenotype secrete miR-200 family members via EVs to attenuate TGF-β-mediated CAF features by targeting ZEB1 in normal fibroblasts. However, EVs derived from CRC cells with a mesenchymal phenotype contain less miR-200 family, thus allowing TGF-β-mediated CAF feature induction.…”

Glycocalyx Acts as a Central Player in the Development of Tumor Microenvironment by Extracellular Vesicles for Angiogenesis and Metastasis

“…The EVs derived from tumor cells contribute to the formation of cancer-associated fibroblasts, inducing the remodeling of tumor stroma via transfer of pro-metastatic factors such as non-coding oncogenic micro ribonucleic acids (miRNAs) [ 37 ]. EV-mediated transferring of miR-200 from metastatic colorectal cancer cells to recipient fibroblasts promotes myofibroblast differentiation and fibronectin expression, shaping the stromal landscape, which is likely to be independent of local TGF-β availability [ 21 ]. EVs from SW620 colorectal cancer cells activate fibroblasts to invade the ECM through upregulation of pro-invasive regulators of membrane protrusion (PDLIM1, MYO1B) and matrix-remodeling proteins (MMP11, EMMPRIN, ADAM10) [ 22 ].…”