BPDE, the Migration and Invasion of Human Trophoblast Cells, and Occurrence of Miscarriage in Humans: Roles of a Novel lncRNA-HZ09

Abstract

Background: Recurrent miscarriage (RM) affects 1%–3% of pregnancies. However, in almost 50% of cases, the cause is unknown. Increasing evidence have shown that benzo(a)pyrene [B(a)P], a representative of polycyclic aromatic hydrocarbons (PAHs), is correlated with miscarriage. However, the underlying mechanisms of B(a)P/benzo(a)pyrene-7,8-dihydrodiol-9,10-epoxide (BPDE)-induced trophoblast cell dysfunctions and miscarriage remain largely unknown. Objective: The objective was to discover the role(s) of a novel lncRNA, lnc-HZ09 , in the regulation of BPDE-inhibited migration and invasion of trophoblast cells and the occurrence of miscarriage. Method: Human trophoblast cells were treated with 0, 0.25, 0.5, BPDE with or without corresponding lnc-HZ09 silencing or overexpression. Using these cells, we evaluated cell migration and invasion, the mRNA and protein levels of members of the PLD1/RAC1/CDC42 pathway, the regulatory roles of lnc-HZ09 in PLD1 transcription and mRNA stability, and lnc-HZ09 transcription and stability. Human villous tissues were collected from RM ( ) group and their matched healthy control (HC, ) group. We evaluated the levels of BPDE-DNA adducts, lnc-HZ09, and the mRNA and protein expression of members of the PLD1/RAC1/CDC42 pathway, and correlated their relative expression levels. We further constructed 0, 0.05 or B(a)P-induced mouse miscarriage model (each ), in which the mRNA and protein expression of members of the Pld1/Rac1/Cdc42 pathway were measured. Results: We identified a novel lnc-HZ09 . Human trophoblast cells treated with lnc-HZ09 exhibited less cell migration and invasion. In addition, the levels of this lncRNA were higher in villous tissues from women with recurrent miscarriage than those from healthy individuals. SP1-mediated PLD1 mRNA levels were lower, and HuR-mediated PLD1 mRNA stability was less in trophoblast cells overexpressing lnc-HZ09 . However, trophoblast cells treated with MSX1 had higher levels of lnc-HZ09 , and METTL3-mediated m6A methylation on lnc-HZ09 resulted in greater lnc-HZ09 RNA stability. In BPDE-treated human trophoblast cells and in RM villous tissues, MSX1-mediated lnc-HZ09 transcription and METTL3-mediated lnc-HZ09 stability were both greater. In our mouse miscarriage model, B(a)P-treated mice had lower mRNA and protein levels of members of the Pld1/Rac1/Cdc42 pathway. Discussion: These results suggest that in human trophoblast cells, BPDE exposure up-regulated lnc-HZ09 level, suppressed PLD1/RAC1/CDC42 pathway, and inhibited migration and invasion, prov...

LncRNA-BC069792 suppresses tumor progression by targeting KCNQ4 in breast cancer

“…Cells with log-growth period were seeded into 24-well plates. The actinomycin D (5 mg/ml) [ 13 ] was added after cell starvation for 24 h. Cells were harvested at 0 h, 0.5 h, 1 h, 4 h, 8 h and 12 h in the 37℃ 5% CO 2 cell incubator and RNA was extracted. Then lncRNA stability was determined by RT-qPCR assay.…”

Failure to Connect: Experimental Evidence that Benzo(a)pyrene Impedes Embryonic Implantation

“… 1 Now, experimental research in Environmental Health Perspectives sheds light on how one ubiquitous pollutant, benzo(a)pyrene [B(a)P], might elevate risk for recurrent miscarriage. 5 …”

“…A by-product of incomplete combustion, B(a)P is a polyaromatic hydrocarbon (PAH) found in tobacco and wood smoke, car exhaust, and grilled foods, among other sources. 6 According to the new study, 5 maternal exposure to B(a)P increased the expression of certain genes and proteins that may interfere with the attachment of a very early stage embryo—called a blastocyst—to the uterine wall. The research was led by Huidong Zhang, a professor at the Eighth Affiliated Hospital, Sun Yat-sen University, in Shenzhen, China.…”

“… 7 – 9 During the new study, Zhang and colleagues focused specifically on developmental effects of the ultimate metabolite of B(a)P: benzo(a)pyrene-7,8-dihydrodiol-9,10-epoxide (BPDE). 5 Previous research by this team and others showed that BPDE inhibits the normal biology of cells called trophoblasts, which form the outer layer of the blastocyst and give rise to the placenta. 10 , 11 For the developing embryo to establish a blood supply, trophoblasts must first migrate to and then invade the endometrial lining of the uterus.…”

“…Zhang and colleagues focused specifically on how BPDE disrupts the activity of long noncoding RNAs (lncRNAs), 5 which have key roles in trophoblast functioning. In an earlier cell study, the team identified 22 lncRNAs that are more active in human trophoblasts after BPDE exposure.…”