[Regulation of traditional Chinese medicine formulae bailong on cAMP-PKA and DAG-PKC signal pathways of human gastric cancer cells].

OBJECTIVE: To evaluate the effects of traditional Chinese medicine formulae (Bailong) on cAMP/PKA and diacylaglycerol (DAG) protein kinase (PKC) pathways of the MGc80-3 cells. METHODS: cAMP level, DAG content and activities of PKA and PKC were measured in different groups: (1) control, (2) 1.8 mg/ml Bailong, (3) 1.8 mg/ml Bailong +20 ug/ml PKA inhibitor, (4) 5 mumol/L PKC inhibitor. RESULTS: When MGc80-3 cells were in treatment with Bailong for 3 hours, cAMP level and PKA activity were 11.27%, and 19.7% higher than that of the control, while DAG content and PKC activity were 47.0% and 64.2% lower than that of the control; When PKC pathway was blocked by PKC inhibitor GF-109203X, cAMP level and PKA activity were increased by 78.8% and 33.5% as against that of the control, while the DAG content and PKC activity were decreased by 40. 3% and 56.3% respectively. When MGc80-3cells were treated with Bailong, and at the same time, blocked PKA pathways by PKA inhibitor, cAMP level and PKA activity were decreased by 46.0% and 28.9%, on the other hand, DAG content and PKC activity were increased by 50.7% and 51.6% as against that of the Bailong group. CONCLUSIONS: (1) There was relationship of causes and result between differentiation of MGc80-3 cells and the signal pathways. (2) Results of this study were similar to that of hexamethylenebisacetamide (HMBA). It is shown that the two signal systems are the foundation of regulative effects of Chinese medicine formulae Bailong or HMBA on proliferation and differentiation in MGc80-3 cells.

Co-regulative effects of the cAMP/PKA and DAG/PKC signal pathways on human gastric cancer cells during differentiation induced by traditional Chinese medicines.

AIM: To evaluate the role of cAMP/PKA and DAG/PKC pathways of MGc80-3 cells treated with a traditional Chinese medicine compound, bailong preparation (bailong). METHODS: cAMP level, DAG content and activities of PKA and PKC were measured in different groups: control; 1.8 g/L bailong; 1.8 g/L bailong + 20 mg/L PKA inhibitor; and 5 µmol/L PKC inhibitor. RESULTS: When MGc80-3 cells were treated with bailong for 3 h, cAMP level and PKA activity were 113% and 19.7% higher than those of the control, while DAG content and PKC activity were 47.0% and 64.2% lower than those of the control. When the PKC pathway was blocked by PKC inhibitor GF-109203 X, cAMP level and PKA activity were increased by 78.8% and 33.5% compared to inhibitor GF-109203 X, and cAMP level and PKA activity were increased by 78.8% and 33.5% compared to the control, while the DAG content and PKC activity were decreased by 40.3% and 56.3%. When MGc80-3 cells were treated with bailong and PKA inhibitor blocked PKA pathways at the same time, cAMP level and PKA activity were decreased by 46.0% and 28.9%. On the other hand, DAG content and PKC activity were increased by 50.7% and 51.6% compared to the bailong group. CONCLUSION: There is a relationship of cause and effect between differentiation of MGc80-3 cells and the signal pathways. The results of this study are similar to that of hexamethylenebisacetamide (HMBA), suggesting that the two signal systems are the foundation of proliferative regulation of MGc80-3 cells treated with Chinese medicine bailong or HMBA.