Abstract:
Objective To explore the impact of preoperative chemotherapy on the expressions of hormone receptors and drug-resistant related proteins in breast cancer tissues.
Methods Ninety-two breast cancer cases with preoperative chemotherapy were enrolled in Jiangsu Cancer Hospital between January 2009 and December 2011. The expressions of ER, PR, P-gp, GST-rt, and TOPO- II were detected and compared using the immunohistochemical streptavidin-peroxidase (S-P) method in breast cancer tissues harvested by ultrasound-guided core needle biopsy and operation.
Results The positive expression rates of ER and PR were 65.2% and 56.5% before chemotherapy and 50.0% and 52.2% after chemotherapy, respectively. The former two had significant differences (P < 0.05). The positive expression rates of P-gp and GST-π, were 54.3% and 32.6% before chemotherapy and 82.6% and 45.7% after chemotherapy, respectively, showing significant differences (P < 0.05). The cases with the expression of both P-gp and GST-π increased from 22 to 32. The positive expression rate ofTOPO- II decreased from 48.9% to 41.3%, showing no significant difference (P>0.05), but with a decreasing trend.
Conclusion Prechemotherapy affects the expression of hormone receptor and the drug-resistant related proteins. Monitoring their expression has a guiding significance for drug selection, prognostic judgment, and the following treatment regimen decision.