HOX gene expression in normal ovary and in the ovarian cancer derived cell lines SK-OV3 and OV-90 cells. Gene expression was determined by QPCR and expressed as a ratio to the amount of expression of the housekeeping gene, β-actin. Abbreviations are used for each HOX gene shown on the x-axis such that, for example, HOXA1 is represented by 'A1'. SEM is indicated by the error bars. P-values of less than 0.0013 (Bonferroni correction for multiple hypothesis testing) for expression in SK-OV3 cells compared to that in normal ovary are denoted *.