Basu D, Nguyen TT, Montone KT, Zhang G, Wang LP, Diehl JA et al.. Evidence for mesenchymal-like sub-populations within squamous cell carcinomas possessing chemoresistance and phenotypic plasticity. Oncogene 29: 4170-4182

Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Philadelphia, PA 19104, USA.
Oncogene (Impact Factor: 8.46). 05/2010; 29(29):4170-82. DOI: 10.1038/onc.2010.170
Source: PubMed


Variable drug responses among malignant cells within individual tumors may represent a barrier to their eradication using chemotherapy. Carcinoma cells expressing mesenchymal markers resist conventional and epidermal growth factor receptor (EGFR)-targeted chemotherapy. In this study, we evaluated whether mesenchymal-like sub-populations within human squamous cell carcinomas (SCCs) with predominantly epithelial features contribute to overall therapy resistance. We identified a mesenchymal-like subset expressing low E-cadherin (Ecad-lo) and high vimentin within the upper aerodigestive tract SCCs. This subset was both isolated from the cell lines and was identified in xenografts and primary clinical specimens. The Ecad-lo subset contained more low-turnover cells, correlating with resistance to the conventional chemotherapeutic paclitaxel in vitro. Epidermal growth factor induced less stimulation of the mitogen-activated protein kinase and phosphatidylinositol-3-kinase pathways in Ecad-lo cells, which was likely due to lower EGFR expression in this subset and correlated with in vivo resistance to the EGFR-targeted antibody, cetuximab. The Ecad-lo and high E-cadherin subsets were dynamic in phenotype, showing the capacity to repopulate each other from single-cell clones. Taken together, these results provide evidence for a low-turnover, mesenchymal-like sub-population in SCCs with diminished EGFR pathway function and intrinsic resistance to conventional and EGFR-targeted chemotherapies.

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Available from: John Alan Diehl, Dec 04, 2014
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    • "Scc9, FaDu and Detroit 562 cells are well-differentiated HNSCC and express epithelial markers (E-cadherin and plakoglobin) but not mesenchymal markers (vimentin or N-cadherin) (Basu et al., 2010; Yang et al., 2008). Chemotherapy of Scc9-xenografts leads to repopulation of the tumors with mesenchymal-like vimentin-positive Scc9 cells that are more resistant to chemotherapy due to a decrease in surface EGFR expression (Basu et al., 2010). "
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