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S179D prolactin (PRL) is an experimentally useful mimic of naturally phosphorylated human prolactin. S179D PRL, but not unmodified PRL, was found to be anti-angiogenic in both the chorioallantoic membrane and corneal assays. Further investigation using human endothelial in vitro models showed reduced cell number, reduced tubule formation in Matrigel, and reduced migration and invasion, as a function of treatment with S179D PRL. Analysis of growth factors in human endothelial cells in response to S179D PRL showed: a decreased expression or release of endogenous PRL, heme-oxygenase-1, basic fibroblast growth factor (bFGF), angiogenin, epidermal growth factor and vascular endothelial growth factor; and an increased expression of inhibitors of matrix metalloproteases. S179D PRL also blocked signaling from bFGF in these cells. We conclude that this molecular mimic of a pituitary hormone is a potent anti-angiogenic protein, partly as a result of its ability to reduce utilization of several well-established endothelial autocrine growth loops, partly by its ability to block signaling from bFGF and partly because of its ability to decrease endothelial migration. These findings suggest that circulating levels of phosphorylated PRL may influence the progression of cancer and, furthermore, that S179D PRL may be a useful anti-angiogenic therapeutic.

Platinum-based therapy remains the cornerstone for cancer therapy; however, its efficacy varies. The role of lipoprotein receptor-mediated lipid entry for cancer development has been reported. Yet, the roles and mechanism of the low-density lipoprotein receptor (LDLR) in chemo-sensitivities are unknown. In the current report, we used epithelial ovarian cancer (EOC), composed of various cellularities, to study this issue. Using public cDNA microarray database and single cohort study, LDLR expressions were positively associated with epithelial ovarian carcinomas (EOCs) platinum-based chemotherapy patients’ disease prognosis. In vitro and in vivo add-in/silencing LDLR was introduced to determine cisplatin sensitivity and cancer growth. Results revealed that knocked-down LDLR could sensitize while overexpressed LDLR could insensitize EOC cells to the cytotoxic effects of cisplatin. Moreover, the trans-omics approaches depicted an LDLR→LPC (Lyso-phosphatidylcholine)→FAM83B (phospholipase-related)→FGFRs (cisplatin sensitivity and phospholipase-related) regulatory axis. Finally, the manipulation of LDLR expression in EOC cells was found to determine the efficacy of cisplatin therapy in terms of tumor suppression. In conclusion, the LDLR→LPC→FAM83B→FGFRs axis is an example of tumor macroenvironmental regulation of therapy outcomes. Relatedly, LDLR expression could serve as a biomarker of chemotherapy sensitivity in EOCs. Significance: this study describes the role of LDLR in the development of insensitivity to platinum-based chemotherapy in epithelial ovarian cancer. The lipidome (e.g., LPC) and transcriptome (e.g., FAM38B) interactions revealed using trans-omics approaches an LDLR→LPC→FAM83B→FGFRs regulatory axis in cancer cells, in an animal model, and in patients.