Figure 3

Distribution of hypoxia inducible factor 1α ( HIF-1α ) ^TAG and HIF-1α ⁷³⁶ mRNA levels in 82 breast tissues determined by real-time quantitative reverse transcription PCR assay. HIF-1α mRNA levels were expressed in normalised copy numbers (NCN) on the basis of TATA box-binding protein (TPB) gene content of the tissues as described in the Methods section. Patients grouped according to histological type of tissues (x axis). HIF-1α ^TAGand HIF-1α ⁷³⁶mRNAs were expressed at higher levels in oestrogen receptor (OR)-negative carcinomas compared to normal/benign tissues (P = 0.009 and P = 0.004 respectively). HIF-1α ^TAGmRNAs were also higher in OR-negative carcinomas compared to OR-positive ones (P = 0.005).