Stromal and epithelial changes in breast cancer following endocrine treatment

ABSTRACT: Patients diagnosed with breast cancer were recruited to an important trial, the Tamoxifen Window Trial, in two series, series A during 1988-1989 and series B during 1989-1990. Some patients received tamoxifen for short windows. Clinical samples (biopsies) for this trial were collected before and after treatment. These biopsies were available as formalin-fixed paraffin-embedded (FFPE) tissue blocks. Responding patients and non-responding patients were determined by the change in the Ki67 scores. Responding patients were identified as those that had demonstrated a reduction in their Ki67 scores, and non-responding patients were identified as those in which Ki67 had not changed or had increased. The change in the percentage of Ki67 positive tumour cells was obtained by comparing the pre-treatment and post-treatment scores and calculating the difference in the scores. Laser capture microdissection (LCM) was utilised to microdissect the epithelial and stromal cells from the post-treatment breast cancer FFPE tissue sections of responding and non-responding patients. Samples obtained following LCM underwent RNA extraction and were subsequently used for gene expression profiling. Post-treatment samples from three responding patients (A29, B42, B61) and three non-responding patients (A15, A19, B59) were identified as suitable for this study and underwent LCM. Samples were analysed using Affymetrix GeneChip® Human Exon 1.0 ST array. No technical replicates were performed. The stromal compartments collected from post-treatment samples of patients B59 and B61 failed to generate the appropriate yield of cDNA following two rounds of amplification and consequently were excluded from further analysis. Array hybridisation of samples were performed in 3 separate batches.

ORGANISM(S): Homo sapiens

SUBMITTER: Azadbakht Narges 

PROVIDER: S-ECPF-GEOD-58598 | biostudies-other |

REPOSITORIES: biostudies-other