We previously reported satisfactory therapeutic results of cisplatin-based cyclic balloon-occluded arterial infusion chemotherapy (BOAI) as neoadjuvant chemotherapy, which enabled treatment by hysterectomy in patients with advanced cervical cancer. We also reported expression of apoptosis among these patients and determined that the bax gene is related to this apoptosis. In the present study, we investigated the relationship between the effectiveness of BOAI therapy and expression of apoptosis regulatory genes and proteins in these cases. The subjects were 27 women with advanced cervical cancer classified as FIGO (International Federation of Gynecology and Obstetrics) stage III or higher who were admitted to the Department of Gynecology, Osaka City University Medical School Hospital between 2000 and 2003. All patients were treated by BOAI, and expression of cancer cell apoptosis was examined by the TUNEL method, expression of bax, bcl-2 and bcl-xL proteins were examined by immunohistochemistry, and expression of bax, bcl-2 and bcl-xL mRNA was examined by quantitative RT-PCR before and 3 days after BOAI. The effectiveness of BOAI therapy was thus determined. The 20 patients in whom BOAI was effective showed significantly higher expression of the bax protein and gene after BOAI, and cancer cell apoptosis was accelerated. On the other hand, the 7 patients in whom BOAI was ineffective showed significantly higher expression of the bcl-xL protein and gene after BOAI. These results suggest that bax/bcl-xL expression can be used as an indicator of the effectiveness of BOAI therapy.