Aspirin inhibits ErbB2 to induce apoptosis in cervical cancer cells

The use of aspirin is associated with a lower risk of many cancer types. However, there are few reports about cervical cancer. The proto-oncogene ErbB2 is overexpressed in cervical cancer, and considered as a therapeutic target. In the present study, we investigated whether aspirin had therapeutic value in cervical cancer and examined the effects of aspirin on the amplification and expression of ErbB2. To investigate the effects of aspirin on apoptosis and proliferation, we tested apoptosis by Hoechst 33258 staining and Annexin V-FITC/PI method; MTT assay and colony formation assay were used to detect proliferation. Induction of apoptosis and inhibition of proliferation were observed in HeLa cells incubated with aspirin. Western blot and immunocytochemical staining showed that aspirin induced a dose- and time-dependent reduction of ErbB2 expression that was due to proteosome-mediated degradation of this protein. To further investigate the underlying mechanism by which aspirin exerts its apoptosis effects, we studied the ErbB2 downstream cell survival signaling pathways and the expression of anti-apoptosis gene Bcl-2. We found that aspirin inhibited the activation of extracellular signal-regulated kinase (ERK) and AKT. The inhibition of Bcl-2 expression was also observed. These data reveal that aspirin significantly induces apoptosis and inhibits proliferation, which maybe via inhibiting ErbB2 downstream cell survival signaling pathways. Taken together, our article describes a novel mechanism of action for anti-tumor activity of aspirin and implicates aspirin as a novel agent for cervical cancer.