Apoptosis induced by neoadjuvant chemotherapy in breast cancer.
OBJECTIVE
To evaluate the relationship between apoptosis induced by chemotherapy and clinical response in breast cancer.


METHODS
Apoptosis index (AI), mutant p53 and Bcl-2 protein expression were evaluated in 44 breast tumour samples from patients submitted to neoadjuvant chemotherapy. Objective response (OR) to primary chemotherapy was observed in 37 patients (84%) and no response (NR) in seven. AI was measured by the rate of apoptotic cells identified using morphological criteria. p53 and Bcl-2 protein expression were evaluated using an immunoperoxidase staining technique.


RESULTS
The median AI change observed between pre-chemotherapy AI and post-chemotherapy AI was 0.84 in the OR group and 0.01 in the NR group, (rho = 0.4; p = 0.006). There was no change in Bcl-2 protein expression following chemotherapy. In the OR group, p53 protein expression was positive in 41.6% of patients before and in 22.2% after chemotherapy (difference = 16.6%; p = 0.03). No change was detected in the NR group.


CONCLUSIONS
A positive correlation was found between the increase in AI and clinical response to neoadjuvant chemotherapy in locally advanced breast cancer.
Department of Gynecology and Obstetrics, School of Medicine of Presidente Prudente--UNOESTE, S/A, Brazil.
Daniel Guimarães
DG
Tiezzi
Jurandyr Moreira
JM
De Andrade
Francisco José
FJ
Cândido dos Reis
Heitor Ricardo Cosiski
HR
Marana
Alfredo
A
Ribeiro-Silva
Marcelo Guimarães
MG
Tiezzi
Antônio Plácido
AP
Pereira
D000328:Adult; D018943:Anthracyclines / Q000627:therapeutic use; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D017209:Apoptosis / Q000187:drug effects / Q000235:genetics; D001943:Breast Neoplasms / Q000737:chemistry / Q000188:drug therapy* / Q000473:pathology*; D001952:Bridged-Ring Compounds / Q000627:therapeutic use; D017024:Chemotherapy, Adjuvant; D003520:Cyclophosphamide / Q000627:therapeutic use; D019008:Drug Resistance, Neoplasm; D015251:Epirubicin / Q000627:therapeutic use; D005260:Female; D005472:Fluorouracil / Q000627:therapeutic use; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D009154:Mutation; D020360:Neoadjuvant Therapy; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000032:analysis; D043823:Taxoids / Q000627:therapeutic use; D016159:Tumor Suppressor Protein p53 / Q000032:analysis
D018943:Anthracyclines; D001952:Bridged-Ring Compounds; D019253:Proto-Oncogene Proteins c-bcl-2; D043823:Taxoids; D016159:Tumor Suppressor Protein p53; C080625:taxane; D015251:Epirubicin; D003520:Cyclophosphamide; D005472:Fluorouracil