cells was not influenced if they were treated with 1(T~(-5)M taxol and 0.1?g/ml colcemid for 2 hrs. either simultaneously or in accession. The secretory activity of these cells was evidently inhibited after treatment with 4?g/ml cytochalasin B for 6 hrs. Our results indicate that the mucus secretion of MGc80-3 human stomach cancer cells closely depended on the presence of both microtubules and microfilaments. We also found that the mucus secretion of MGc80-3 cells was enhanced by treatment with l?g/ml pilocarpine for 6 hrs. The proliferation of MGc80-3 cell population was inhibited by thiazolidine-4 carboxylic acid. However, the secretory activity of these cells was evidently enhanced after treatment with 0.1?g/ml thiazolidine-4 carboxylic acid for 10 hrs. The stimulating effect of pilocarpine and thiazolidine-4 carboxylic acid disappeared after the microtubules and microfilaments were disassembled by treatment with colcemid and cytochalasin B. In addition, our experiments also show that the mucus secretion of these cells was increased after treatment with ImM db-cAMP. These findings convincingly support the assumption that motile events placed under the control of the microtubular-microfilamentous system are intimately involved in the mucus secretion of MGc80-3 human stomach cancer cells. cells was not influenced if they were treated with 1(T~(-5)M taxol and 0.1?g/ml colcemid for 2 hrs. either simultaneously or in accession. The secretory activity of these cells was evidently inhibited after treatment with 4?g/ml cytochalasin B for 6 hrs. Our results indicate that the mucus secretion of MGc80-3 human stomach cancer cells closely depended on the presence of both microtubules and microfilaments. We also found that the mucus secretion of MGc80-3 cells was enhanced by treatment with l?g/ml pilocarpine for 6 hrs. The proliferation of MGc80-3 cell population was inhibited by thiazolidine-4 carboxylic acid. However, the secretory activity of these cells was evidently enhanced after treatment with 0.1?g/ml thiazolidine-4 carboxylic acid for 10 hrs. The stimulating effect of pilocarpine and thiazolidine-4 carboxylic acid disappeared after the microtubules and microfilaments were disassembled by treatment with colcemid and cytochalasin B. In addition, our experiments also show that the mucus secretion of these cells was increased after treatment with ImM db-cAMP. These findings convincingly support the assumption that motile events placed under the control of the microtubular-microfilamentous system are intimately involved in the mucus secretion of MGc80-3 human stomach cancer cells.