Increased Cell Detachment Ratio of Mesenchymal-Type Lung Cancer Cells on pH-Responsive Chitosan through the β3 Integrin

Abstract

Chitosan is sensitive to environmental pH values due to its electric property. This study investigates whether the pH-responsive chitosan assay can provide a simple method to evaluate the aggressive behavior of cancer cells with cell detachment ratio. The epithelial–mesenchymal transition (EMT) is induced with transforming growth factor-β1 (TGF-β1) in the human non-small cell lung cancer cell line (A549). EMT-induced cells and untreated cells are cultured on chitosan substrates at pH 6.99 for 24 h, followed by pH 7.65 for 1 h. The cell detachment ratio (CDR) on pH-responsive chitosan rises with an increasing of the TGF-β1 concentration. The protein array reveals that the expression levels of the α2, α3, α5, β2, and β3 integrins are higher in EMT-induced A549 cells than in untreated cells. A further inhibition assay shows that adding β3 integrin blocking antibodies significantly decreases the CDR of EMT-induced cells from 32.7 ± 5.7% to 17.8 ± 2.1%. The CDR of mesenchymal-type lung cancer cells increases on pH-responsive chitosan through the β3 integrin. Notably, the CDR can be theoretically predicted according to the individual CDR on the pH-responsive chitosan surface, irrespective of heterogeneous cell mixture. The pH-responsive chitosan assay serves as a simple in vitro model to investigate the aggressive behavior of lung cancer including the heterogeneous cell population.

pH-driven continuous stem cell production with enhanced regenerative capacity from polyamide/chitosan surfaces

“…For the achievement of continuous cell production, the prepared PA/CS blends were examined using the modified cell detachment assay developed in the previous study [ 29 ], as illustrated in Fig. 3 A.…”

“…Cell numbers of the detached and the remaining adherent cells on the blended substrates were determined by CyQUANT assay kit (C35006; Invitrogen, Thermo Fisher Scientific) according to the manufacturer's instructions. Cell detachment ratio was calculated as the previous reported method [ 29 ].…”

Role of epithelial cell-mesenchymal transition regulators in molecular typing and prognosis of colon cancer

“…EMT is a developmental process that promotes the transition of epithelial cells to migratory mesenchymal cells (27). Previous articles have reported that EMT is involved in the occurrence, development, and metastasis of tumors, in which it plays an important role (28,29), with a great correlation with cancer metastasis (30). Due to the different driving factors of EMT in different tumor types or in different stages of the occurrence and development of the same tumor, its role in tumor metastasis is not the same (31)(32)(33)(34).…”