High Immune Expression of Progesterone-Induced Blocking Factor in Epithelial Ovarian Cancer

Identification and prioritization of tumour-associated antigens for immunotherapeutic and diagnostic capacity in epithelial ovarian cancer: a systematic literature review

Epithelial ovarian cancer (EOC) is a prevalent carcinoma in the female population associated with poor prognostic outcomes, in part due to the late stage of the disease at diagnosis. Aiming to identify tumour-associated antigens (TAAs) with the potential to facilitate earlier detection and targeted therapy of EOC, five scientific literature repositories were systemically searched for primary literature sources reporting the expression of a TAA in the tissue or serum of adult females diagnosed with EOC and healthy women. We identified 7120 articles of which 32 met our inclusion criteria and passed the bias-quality assessment. Subsequently, data were collated on 29 TAAs whose expression had been analysed in 2181 patients and 589 healthy individuals. Reports of CA125 and EpCAM expression were numerous while tissue expression data were available for 28 TAAs. Data were segregated into three meta-cohorts for statistical scrutiny and their capacity for diagnostic and treatment targeting was assessed. We showed that CA-125 was expressed homogenously in EOC patients while EpCAM was expressed heterogeneously. CA-125 was the most promising TAA target for both diagnosis and treatment, gaining a priority score of 12 (/12) while EpCAM gained a priority score of seven. Tissue expression of EOC TAAs was homogenous; 90% of the EOC population express any identified TAA while just 20% of healthy individuals will be positive for the same TAA. We suggest TAA profiling should be a fundamental aspect of EOC diagnosis, sitting alongside the FIGO framework, promoting reduced mortality and directing the development of TAA-targeted therapeutics.

Enhanced ZNF521 expression induces an aggressive phenotype in human ovarian carcinoma cell lines

Epithelial ovarian carcinoma (EOC) is the most lethal gynecological tumor, that almost inevitably relapses and develops chemo-resistance. A better understanding of molecular events underlying the biological behavior of this tumor, as well as identification of new biomarkers and therapeutic targets are the prerequisite to improve its clinical management. ZNF521 gene amplifications are present in >6% of OCs and its overexpression is associated with poor prognosis, suggesting that it may play an important role in OC. Increased ZNF521 expression resulted in an enhancement of OC HeyA8 and ES-2 cell growth and motility. Analysis of RNA isolated from transduced cells by RNA-Seq and qRT-PCR revealed that several genes involved in growth, proliferation, migration and tumor invasiveness are differentially expressed following increased ZNF521 expression. The data illustrate a novel biological role of ZNF521 in OC that, thanks to the early and easy detection by RNA-Seq, can be used as biomarker for identification and treatment of OC patients.

Progestogens and immunology

Fifty percent of fetal antigens are of paternal origin. These are recognized by the maternal immune system, thereby resulting in lymphocyte activation and the induction of progesterone receptors (PRs) in immune cells. Upon binding of progesterone to PRs on lymphocytes, a downstream mediator called progesterone-induced blocking factor (PIBF) is produced. The full-length PIBF is a 90 kDa protein; however, because of alternative splicing, several smaller isoforms are also produced. While the 90 kDa molecule plays a role in cell cycle regulation, the small isoforms are localized in the cytoplasm, and after secretion, they bind to their receptors on other cells and act in a cytokine-like manner. The communication between the embryo and the maternal immune system is established through PIBF-containing extracellular vesicles. PIBF induces an increased production of Th2 cytokines and inhibits degranulation of NK cells, and by regulating the maternal immune response, it contributes to successful implantation and maintenance of pregnancy.

Progesterone-Related Immune Modulation of Pregnancy and Labor

Pregnancy involves a complex interplay between maternal neuroendocrine and immunological systems in order to establish and sustain a growing fetus. It is thought that the uterus at pregnancy transitions from quiescent to laboring state in response to interactions between maternal and fetal systems at least partly via altered neuroendocrine signaling. Progesterone (P4) is a vital hormone in maternal reproductive tissues and immune cells during pregnancy. As such, P4 is widely used in clinical interventions to improve the chance of embryo implantation, as well as reduce the risk of miscarriage and premature labor. Here we review research to date that focus on the pathways through which P4 mediates its actions on both the maternal reproductive and immune system. We will dissect the role of P4 as a modulator of inflammation, both systemic and intrinsic to the uterus, during human pregnancy and labor.