HER-2 expression in local advanced breast cancer and the efficacy of neoadjuvant chemotherapy regimens / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the relationship between HER-2 expression and the efficacy of neoadjuvant chemotherapy in local advanced breast cancer.</p><p><b>METHODS</b>Different neoadjuvant chemotherapy regimens, namely CMF, CEF, and NEF, were administered in 132 patients with local advanced breast cancer for 2 cycles, each lasting for 28 days. According to the criteria recommended by WHO, the efficacy and safety of the regimens were evaluated after two cycles of neoadjuvant chemotherapy. HER-2 expression was examined by immunohistochemistry using specific monoclonal antibodies before chemotherapy and after surgery.</p><p><b>RESULTS</b>The overall response rate (RR) of CMF, CEF, and NEF regimens were 39.5% (17/43), 54.3% (25/46) and 72.1% (31/43), with incidence of leukopenia of 34.9% (15/43), 58.7% (27/46) and 60.5% (26/43), respectively. Other adverse effects including decreased hemoglobin (Hb) level, thrombocytopenia, gastrointestinal irritation and alopecia were similar between the 3 groups (P>0.05). No significant variation in HER-2 expression occurred after administration of the 3 regimens. The overall RR to CMF regimen in HER-2-negative breast cancer patients was significantly higher than that in HER-2-positive patients, but showed no significant difference with CEF and NEF regimens.</p><p><b>CONCLUSION</b>HER-2 expression is not decreased after neoadjuvant chemotherapy in breast cancer patients, and HER-2-positive breast cancer can be resistant to CMF regimen, but not to CEF and NEF regimens.</p>

Chemopreventive effect of celecoxib against DMBA-induced breast cancer and its mechanism / 南方医科大学学报

<p><b>OBJECTIVE</b>To evaluate the chemopreventive effect of celecoxib, a specific cyclooxegenease-2 (COX-2) inhibitor, on chemically induced breast cancer of rats and its effect on COX-2 expression.</p><p><b>METHODS</b>7, 12-dimethylbenz anthracene (DMBA) was administered intragastrically in SD female rats to establish breast cancer models, which were divided subsequently into control group, tamoxifen group and celecoxib group to receive different treatments accordingly. The occurrence rate of breast cancer was observed and the effect of celecoxib on COX-2 and vascular endothelial growth factor (VEGF) expressions assayed by immunohistochemical SP method.</p><p><b>RESULTS</b>The incidence of breast cancer in tamoxifen group (48.15%) and celecoxib group (50.00%) were both significantly lower than that in the control group (85.71%; P=0.003 and P=0.004, respectively). The positivity rate of COX-2 expression in celecoxib group (28.57%) was significantly lower than those of tamoxifen group (48.15%) and control group (83.33%; P=0.001 and P=0.035, respectively). The positivity rate of VEGF expression in celecoxib group (42.86%) was significantly lower than that of control group (79.17%, P=0.023), but comparable with that in tamoxifen group (46.15%, P=0.863).</p><p><b>CONCLUSION</b>Celecoxib can significantly suppress DMBA-induced breast cancer in female rats possibly through down-regulation of COX-2 and VEGF expressions.</p>