Desmocollin-2 affects the adhesive strength and cytoskeletal arrangement in esophageal squamous cell carcinoma cells

Desmocollin-2 (DSC2), a transmembrane glycoprotein belonging to the desmosomal cadherin family, has been found to be differentially expressed in several types of cancer and to be involved in tumor progression. The tumor metastasis suppressing property of DSC2 in esophageal squamous cell carcinoma (ESCC) has been described, however, its contribution to cell cohesion in ESCC remains to be elucidated. In the present study, using RNA interference (RNAi), the expression of DSC2 was silenced in SHEEC and KYSE510 cells. Hanging drop and fragmentation assays were performed to investigate the role of DSC2 in cell-cell adhesion. Western blot analysis and confocal microscopy were used to analyze the expression and localization of cell adhesion molecules and cytoskeletal arrangement. The results demonstrated that DSC2 knock down by RNAi caused defects in cell-cell adhesion and a concomitant reduction in desmosomal protein expression and adherens junction molecule distribution. A decrease in the expression of DSC2 caused an increase in free γ-catenin levels, thus promoting its recruitment to the adherens junction complex. In addition, the RNAi-mediated inhibition of DSC2 led to keratin intermediate filament retraction and filamentous-actin cytoskeleton rearrangement. Taken together, these data support our previous findings and the proposal that DSC2 may be involved in the regulation of the invasive behavior of cells by a mechanism that controls cell-cell attachment and cytoskeleton rearrangement.