IGFBP7 expression in ovarian cancer cell lines. A and C, Gene expression microarray analysis depicting the normalized expression values of IGFBP7 mRNA in tumourigenic parental cell line (OV90 neor), three non-tumourigenic hybrids (RH5, RH6, RH10) and in six additional EOC cell lines, using Affymetrix U133Plus2 microarray platform in A, and the custom Ziplex® Research System gene expression array platform in C. B and E, IGFBP7 intracellular protein level in EOC cell lines and the three non-tumourigenic hybrids was analysed by western blot analysis. α-tubulin was used as a loading control. D, Semi-quantitative RT-PCR analysis of IGFBP7 in seven EOC cell lines using 2 different couples of primers. The expression of 18S is shown as an internal control.