Objective: To observe the expression of Bcl-2 and Bax proteins and cell apoptosis induced by preoperative lymphatic chemotherapy with epirubicin-activated carbon suspension (Epi-CH) in the cells of axillary metastatic lymph node of breast cancer and investigate the mechanism.
Methods: Sixty patients with breast cancer of stages II-III were randomly divided into two groups. Forty patients in Epi-CH group were injected with 10 mg Epi-CH in the tissue around the primary tumor or biopsy excision 72 h before operation. Twenty patients in the control group were injected with 10 mg epirubicin solution in the same region. The stained lymph nodes full of tumor cells in Epi-CH group and the non-stained nodes in the control group were selected for apoptotic detection by TUNEL method. The expression of Bcl-2 and Bax proteins were examined by SP immunohistochemistry.
Results: The apoptotic index of the metastatic cancer cells in Epi-CH group was increased remarkably in comparison with that in the control group [(9.5+/-2.7) % vs (3.8+/-1.4) %, P<0.01). Compared with the control group, the expression of Bcl-2 and Bax proteins were up-regulated significantly in Epi-CH group (P<0.05 and P<0.01, respectively), resulting in decreased ratio of Bcl-2/Bax.
Conclusion: Lymphatic chemotherapy can promote cell apotosis in axillary metastasis of breast cancer, which may result from decreased ratio of Bcl-2/Bax.