Primary Cilia in Trophoblastic Cells

Abstract

The pathogenesis of preeclampsia, a pregnancy-related disease, is not completely understood. The primary cilium transduces a diverse array of signaling pathways important for vital cellular activities. Primary cilia were reported to facilitate trophoblastic cell invasion. We hypothesized their further functions in trophoblasts and were interested in related molecular mechanisms. We systematically examined the presence, length and percentage of the primary cilium, its mediated signal transduction, and its connection to trophoblast function. Various cellular and molecular methods were used including immunofluorescence staining, spheroid formation, gene analysis, invasion and tube formation assays with trophoblastic cell lines, primary trophoblasts, and placental tissues. We show that primary cilia are present in various trophoblastic cell lines derived from first trimester placentas. Cilia are also observable in primary trophoblasts, though in a small quantity. Importantly, primary cilia are shortened in trophoblastic cells derived from preeclamptic placentas. Mechanistically, interleukin-6, tumor necrosis factor-α or sera from patients with preeclampsia are able to reduce the length of primary cilia and impair the important sonic hedgehog signaling pathway. Functionally, trophoblastic cells with defective cilia display severe failures in their key functions, like migration, invasion and tube formation, also observed in trophoblastic cells depleted of the intraflagellar transport protein 88. This is accompanied by reduced gene expression of matrix metallopeptidases, vascular endothelial growth factor, and placental growth factor. This work highlights the significance of primary cilia in the functions of trophoblastic cells. Dysfunctional cilia may lead to compromised migration, invasion, and endothelial remodeling of trophoblastic cells, contributing to the development of preeclampsia.

Monosomy X in isogenic human iPSC-derived trophoblast model impacts expression modules preserved in human placenta

“…4 C and D ). Recent reports show the primary cilium is important for proper human trophoblast invasion and migration ( 75 , 76 ). The primary cilium also has an inverse relationship with NRF2 ( 77 – 79 ), NRF2 can activate PlGF expression directly ( 80 ), and NRF2 has been linked with birth outcomes in humans ( 72 , 73 ) and mice ( 81 , 82 ).…”

“…For example, it is unclear whether higher expression of primary cilia components merely reflects the ciliary resynthesis in actively cycling 45,X cells or altered function of this important signaling organelle. In contrast to mouse trophoblasts, human trophoblasts carry cilia ( 75 , 76 ), and cilia regulate autophagy and NRF2 ( 79 ). Curiously, lysosomal genes were widely down-regulated in 45,X BAP samples ( Fig.…”

“…4E) is particularly striking. Recent reports show the primary cilium is important for proper human trophoblast invasion and migration (82,83). The primary cilium also has an inverse relationship with NRF2 (84-86), and NRF2 can activate PlGF expression directly (87).…”

Monosomy X in isogenic human iPSC-derived trophoblast model impacts expression modules preserved in human placenta

“…4E) is particularly striking. Recent reports show the primary cilium is important for proper human trophoblast invasion and migration (82, 83). The primary cilium also has an inverse relationship with NRF2 (84–86), and NRF2 can activate PlGF expression directly (87).…”

Mitotic Centromere-Associated Kinesin (MCAK/KIF2C) Regulates Cell Migration and Invasion by Modulating Microtubule Dynamics and Focal Adhesion Turnover

“…At least thirty random cells per experiment were analyzed and the experiments were repeated independently three times. The patterns of motility were evaluated as descripted previously [28]. The accumulated distance was approximated as the sum of all euclidian distances between the successive points.…”