Whole blood RNA expression profiles in ovarian cancer patients with or without residual tumors after primary cytoreductive surgery

Significant improvements in the treatment results of ovarian cancer havebeen achieved during the last decades, but further improvements require additionalmethods identifying signs of the disease and its biological behavior, preferablyby a simple blood test. We hypothesized that peripheral blood leukocytes may expressgenes that carry such clinical information. Therefore, we studied the relativegene expressions of 168 cancer- and metastasis-specific genes in blood samplesfrom ovarian cancer patients with different prognoses after primary cytoreductivesurgery. Total RNA was extracted from whole blood and the relative gene expressionprofile of 168 genes were analyzed using real-time qPCR assays. Two groups ofpatients were analyzed; one group with residual tumor mass after primary surgery,and one group where the tumor was macroscopically radically resected, resultingin no visible tumor mass left behind. The group with the remaining tumor massafter surgery showed significantly different gene expression profiles comparedto the group with no remaining tumor mass. Differences were noted for the metastasisassociated 1 family, member 2 gene (MTA2), the TNF, α-catenin, interleukin 1β,the KiSS-1 metastasis suppressor and the matrix metallo-proteinase 10 genes. Allgenes were downregulated with a fold-change between 1.15 to 1.57; there were noupregulated genes. Thus, a signature of genes involved in metastasis, invasionand inflammation was found to be significantly downregulated in native unstimulatedblood leukocytes from ovarian cancer patients with a poor prognosis. Preoperativelyit may serve as a guide to the biology of the tumor and postoperatively in theoptimization of adjuvant treatment of ovarian cancer patients.