Suppression of MAGE-A10 alters the metastatic phenotype of tongue squamous cell carcinoma cells

Abstract

MAGE-A10 is a member of the MAGE protein family (melanoma associated antigen) which is overexpressed in cancer cells. Although MAGE-A10 has been characterized for some time and is generally associated to metastasis its function remains unknown. Here we describe experiments using as models oral squamous cell carcinoma (OSCC) cell lines displaying increasing metastatic potential (LN1 and LN2). These cell lines were transduced with lentivirus particles coding for short hairpin against MAGE-A10 mRNA. Repression of MAGE-A10 expression in LN2 cells altered their morphology and impaired growth of LN1 and LN2 cell lines. Furthermore, repression of MAGE-A10 expression increased cell-cell and cell matrix adhesion. Furthermore shMAGEA10 cells were shown to assemble aberrantly on a 3D culture system (microspheroids) when compared to cells transduced with the control scrambled construct. Cell migration was inhibited in knocked down cells as revealed by two different migration assays, wound healing and a phagokinetic track motility assay. In vitro invasion assay using a leiomyoma tissue derived matrix (myogel) showed that shMAGEA10 LN1 and shMAGEA10 LN2 cells displayed a significantly diminished ability to penetrate the matrices. Concomitantly, the expression of E-cadherin, N-cadherin and vimentin genes was analyzed. shMAGEA10 activated the expression of E-cadherin and repression N-cadherin and vimentin transcription.Taken together the results indicate that MAGE-A10 exerts its effects at the level of the epithelial-mesenchymal transition (EMT) presumably by regulating the expression of adhesion molecules.

Isothermal Microcalorimetry of Tumor Cells: Enhanced Thermogenesis by Metastatic Cells

“…For example, MAGE proteins are known to be assembled with E3 RING ubiquitin alloys to form MAGE-RING alloys (MRLs) that function in many cell lines, including tumor cell proliferation (28) and total heat production. As shown in a previous paper (12), by silencing MAGEA10 in LN-1 and LN-2 cells, we observed a reduction as measured by migration and invasion. Indeed, by inhibiting the polymerization of the actin with cytochalasin D, we observed a smaller heat release, especially in the more aggressive cell line (Figure 3).…”

“…As we observed this increase in heat release exclusively in metastatic cell lines among the different tissues used (Figure 1), we decided to investigate what would be the interference, an increase of enthalpy, modulating MAGEA10, a protein closely related to the metastatic characteristics of tongue squamous carcinoma cells as shown in a paper by our group (12). Silencing this protein promotes a significant reduction in heat release (Figure 2), particularly in LN-2 cells.…”

“…Stable specific suppression of MAGEA10 mRNA was achieved by transduction of lentiviral particles expressing oligonucleotides bearing a short hairpin structure as described elsewhere (12).…”

“…Thus, we tested next whether the thermogenic differences observed in Figure 1 could be affected by the suppression of a protein that knowingly mediates adhesive properties of the LN cells. In a previous publication we have demonstrated that protein MAGEA10, which is highly expressed in metastatic cells, was involved in both, adhesion and motility of LN cells (12). Therefore, we carried out microcalorimetry experiments with LN cells stably suppressed for MAGEA10.…”

pMHC Structural Comparisons as a Pivotal Element to Detect and Validate T-Cell Targets for Vaccine Development and Immunotherapy—A New Methodological Proposal

“…Some studies have shown that these proteins may also be important for different aspects of tumor biology, such as for the development of metastasis [69][70][71]. Mendonça et al [72], when investigating the roles of MAGE-A10 in squamous cell carcinoma cell lines, demonstrated that this protein is indeed involved in the epithelial to mesenchymal transition (EMT). This relation should be explained by the interference with the elements of the cytoskeleton.…”