Epac1, PDE4, and PKC protein expression and their association with AKAP95, Cx43, and cyclinD2/E1 in breast cancer tissues

BACKGROUND This study was conducted to investigate the exchange protein directly activated by cAMP (Epac1), PDE4, and PKC expression in breast cancer tissues, and the correlation between these proteins and AKAP95, Cx43, cyclin D2, and cyclin E1. METHODS PV-9000 two-step immunohistochemistry was used to analyze protein expression. RESULTS The positive rate of Epac1 protein expression in breast cancer tissues (58%) was higher than in para-carcinoma tissues (10%) (P < 0.05). There were no significant differences in the positive rates of PDE4 and PKC expression between breast cancer and para-carcinoma tissues (P > 0.05). The positive expression rate of PDE4 was higher in the P53 protein positive group compared to the P53 negative group (P < 0.05). Correlations between Epac1 and cyclin D2, PDE4 and cyclin D2, AKAP95 and PKC, Cx43 and PKC, and cyclin D2 and PKC proteins were observed (P < 0.05). CONCLUSION Epac1 expression in breast cancer tissues was increased, suggesting that the protein may be involved in the development of breast cancer. Correlations between Epac1 and cyclin D2, PDE4 and cyclin D2, AKAP95 and PKC, Cx43 and PKC, and cyclin D2 and PKC proteins suggested synergistic effects among these proteins in the development of breast cancer.