Fig. 7

Increased expression of genes involved in PI3K-AKT signaling in cancer-associated fibroblasts and cancer epithelial cells from ovarian cancer patients is associated with worse overall survival. A Expression levels [log2(norm_count + 1)] of ligands and receptors of the PI3K-AKT signaling pathway in ovarian cystadenocarcinoma (n = 419) of The Cancer Genome Atlas (TCGA) compared to normal ovarian tissues (n = 88) tissues of Genotype-Tissue Expression (GTEx). Rows (for ligand or receptor genes) were ordered based on a marker selection (signal to noise) that highlights the differences in the expression profile [log2(norm_count + 1)] of GTEx tissues when compared to the TCGA tissues. Twenty genes exhibited increased expression levels and were selected to test their association with overall survival. B Forest plots for these twenty ligand and receptor genes of the PI3K-AKT signaling pathway in two cohorts of patients with ovarian cancer (TCGA, n = 557 and GSE9891, n = 264) available on the Kaplan–Meier (KM) plotter [37]. The hazard ratio (HR) with 95% confidence intervals (CI) determined by Cox proportional hazards model was used to evaluate the association between gene expression values and overall survival. The statistical significance was determined by a log-rank test. C Representative Kaplan–Meier curves of overall survival for patients with ovarian cancer (TCGA and GSE9891) based on the expression of IGF2, COL1A2, IGF1, and FGFR2