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PubMed · 9538132

Decrease in gamma-actin expression, disruption of actin microfilaments and alterations in cell adhesion systems associated with acquisition of metastatic capacity in human salivary gland adenocarcinoma cell clones.

H Suzuki·H Nagata·Y Shimada·A Konno
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Abstract

In order to clarify how cytoskeletons and adhesion systems change through acquisition of metastatic capacity in a cancer cell, we examined the expressions of beta- and gamma-actin, the morphology of actin microfilaments and focal contacts, and also the expression of vinculin in a salivary gland adenocarcinoma cell clone cl-1, which acquired metastatic capacity, in comparison with its original clone HSGc lacking metastatic ability. Two-dimensional gel electrophoresis of Triton-insoluble fractions and combined Western blot analysis by immunostaining with anti actin-isoform antibodies showed that the expression of gamma-actin was somewhat lower than that of beta-actin in HSGc, and cl-1 expressed a comparable amount of beta-actin to HSGc, whereas gamma-actin expression by cl-1 was far less than that by HSGc. Northern blot analysis demonstrated that there was little difference in the level of beta-actin mRNA between HSGc and cl-1, while the level of gamma-actin was markedly decreased in cl-1 as compared with HSGc. In terms of morphology, cl-1 cells showed disruption of actin microfilaments and a decrease in the size and number of focal contacts on the cell surface. Furthermore, cl-1 showed decreased expression of vinculin, which became obscured even at the end of actin microfilaments. These results demonstrated that a decrease in gamma-actin, disruption of actin microfilaments, and suppression of focal contacts as well as vinculin take place in the transformation from a non-metastatic condition to a metastatic one in the human salivary gland adenocarcinoma cell clones. Thus, it was strongly suggested that these changes contribute to a decrease in cell adhesiveness and an increase in cell motility, which is probably a major cause for acquisition of metastatic potential.

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Actin CytoskeletonActinsAdenocarcinomaBlotting, WesternCell AdhesionClone CellsElectrophoresis, Gel, Two-DimensionalFluorescent Antibody TechniqueHumansNeoplasm MetastasisSalivary Gland NeoplasmsTumor Cells, CulturedVinculinJournal Article

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H Suzuki, H Nagata, Y Shimada, A Konno. 1998. Decrease in gamma-actin expression, disruption of actin microfilaments and alterations in cell adhesion systems associated with acquisition of metastatic capacity in human salivary gland adenocarcinoma cell clones.. https://doi.org/10.3892/ijo.12.5.1079

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