Objectives: This study aimed to analyze the expression of epithelial-mesenchymal transition (EMT) markers, E-cadherin, and alpha-smooth muscle actin (α-SMA) in CD44+ cancer stem cells (CSCs) compared to parental cells to shed light on the possible role of CSCs in the invasion and metastasis of tongue squamous cell carcinoma (TSCC).
Materials and Methods: Three tongue squamous cell carcinoma cell lines were used in this study. Cells were cultured for cancer stem cell screening and isolation. Tumor cells underwent CD44-based fluorescence-activated cell sorting analysis. Subsequently the expression of E-cadherin and α-SMA in CSCs sub-population and parental cells was evaluated using quantitative real-time PCR.
Results: The three cell lines displayed stable CD44 expression levels. Moreover, E-cadherin recorded a significantly higher value in parental cells compared to CSCs sub-population, whereas α-SMA recorded a significantly lower value in parental cells compared to CSCs sub-population. A very strong negative correlation was noted between E-cadherin and each of α-SMA and CD44, whereas a very strong positive correlation was noted between α-SMA and CD44.
Conclusion: The findings of our study indicated that TSSC harbors a sub-population of CD44+ CSCs that exhibited enhanced EMT features compared to other cell populations.
Our data provide new evidence in support of a potential link between α-SMA expression and CSC features which may have relevant implications for the development of cancer stem cell-based treatment options.