Upregulated lnc-HZ02 and miR-hz02 inhibited migration and invasion by downregulating the FAK/SRC/PI3K/AKT pathway in BPDE-treated trophoblast cells

BaP/BPDE suppresses homologous recombination repair in human trophoblast cells to induce miscarriage: The roles of lnc-HZ08

Benzo(a)pyrene (BaP) or benzo (a) pyrene 7,8-dihydrodiol-9,10-epoxide (BPDE) exposure causes trophoblast cell dysfunctions and induces miscarriage, which is generally epigenetically regulated. Homologous recombination (HR) repair of DNA double strand break (DSB) plays a crucial role in maintenance of genetic stability and cell normal functions. However, whether BaP/BPDE might suppress HR repair in human trophoblast cells to induce miscarriage, as well as its epigenetic regulatory mechanism, is largely unclear. In this study, we find that BaP/BPDE suppresses HR repair of DSB in trophoblast cells and eventually induces miscarriage by up-regulating lnc-HZ08. In mechanism, lnc-HZ08 (1) down-regulates the expression levels of FOXA1 (forkhead box A1) and thus suppresses FOXA1-mediated mRNA transcription of BRCA1 (Breast cancer susceptibility gene 1) and CtIP (CtBP-interacting protein), (2) impairs BRCA1 and CtIP protein interactions by competitive binding with CtIP through lnc-HZ08-1 fragment, and also (3) suppresses BRCA1-mediated CtIP ubiquitination without affecting CtIP stability, three of which eventually suppress HR repair in human trophoblast cells. Supplement with murine Ctip could efficiently restore (i.e. increase) HR repair and alleviate miscarriage in BaP-exposed mouse model. Collectively, this study not only reveals the association and causality among BaP/BPDE exposure, the defective HR repair, and miscarriage, but also discovers novel mechanism in lnc-HZ08-regulated BRCA1/CtIP-mediated HR repair, bridging epigenetic regulation and genetic instability and also providing an efficient approach for treatment against BaP/BPDE-induced unexplained miscarriage.

Exposure to BaA inhibits trophoblast cell invasion and induces miscarriage by regulating the DEC1/ARHGAP5 axis and promoting ubiquitination-mediated degradation of MMP2

Benz[a]anthracene (BaA), a hazardous polycyclic aromatic hydrocarbon classified by the EPA, is a probable reproductive toxicant. Epidemiological studies suggest that BaA exposure may be a risk factor for recurrent miscarriage (RM). However, the underlying mechanisms are not well understood. This study identified DEC1 as a key gene through RNA-seq and single-cell RNA sequencing analysis. DEC1 expression was found to be downregulated in villous tissues from women with RM and in primary extravillous trophoblasts (EVTs) exposed to BaA. BaA suppressed DEC1 expression by promoting abnormal methylation patterns. Further analysis revealed that ARHGAP5 is a direct target of DEC1 in EVTs, where DEC1 inhibits trophoblast invasion by directly regulating ARHGAP5 transcription. Additionally, BaA destabilized matrix metalloproteinase 2 (MMP2) by activating the aryl hydrocarbon receptor (AhR) and promoting E3 ubiquitin ligase MID1-mediated degradation. In a mouse model, BaA induced miscarriage by modulating the DEC1/ARHGAP5 and MID1/MMP2 axes. Notably, BaA-induced miscarriage in mice was prevented by DEC1 overexpression or MID1 knockdown. These findings indicate that BaA exposure leads to miscarriage by suppressing the DEC1/ARHGAP5 pathway and enhancing the MID1/MMP2 pathway in human EVTs.

Environmental BaP/BPDE suppressed trophoblast cell invasion/migration and induced miscarriage by down-regulating lnc-HZ01/MEST/VIM axis

Environmental benzo(a)pyrene (BaP) and itsmetabolite benzo(a)pyrene-7, 8-dihydrodiol-9, 10-epoxide (BPDE), classic endocrine disrupting chemical and persistent organic pollutant, could cause miscarriage. However, the detailed mechanisms are still largely unclear and should be further explored. In this study, we discovered that exposure of trophoblast cells with BPDE could suppressed cell invasion/migration by inhibiting MEST/VIM (Vimentin) pathway. Moreover, BPDE exposure also increased lnc-HZ01 expression level, which further inhibited MEST/VIM pathway and then suppressed invasion/migration. Knockdown of lnc-HZ01 or overexpression of MEST could efficiently rescue invasion/migration of BPDE-exposed Swan 71 cells. Furthermore, lnc-HZ01 was highly expressed and MEST/VIM were lowly expressed in recurrent miscarriage (RM) villous tissues compared with healthy control (HC) group. Finally, we also found that BaP exposure inhibited murine Mest/Vim pathway in placental tissues and induced miscarriage in BaP-exposed mice. Therefore, the regulatory mechanisms were similar in BPDE-exposed human trophoblast cells, RM villous tissues, and placental tissues of BaP-exposed mice with miscarriage, building a bridge to connect BaP/BPDE exposure, invasion/migration, and miscarriage. This study provided novel insights in the toxicological effects and molecular mechanisms of BaP/BPDE-induced miscarriage, which is helpful for better elucidating the toxicological risks of BaP/BPDE on female reproduction.

The novel lnc-HZ12 suppresses autophagy degradation of BBC3 by preventing its interactions with HSPA8 to induce trophoblast cell apoptosis

Abnormal expression of long non-coding RNAs (lncRNAs) is associated with the dysfunctions of human trophoblast cells and the occurrence of miscarriage (abnormal early embryo loss). BBC3/PUMA (BCL2 binding component 3) plays significant roles in regulation of cell apoptosis. However, whether specific lncRNAs might regulate BBC3 in trophoblast cells and further induce apoptosis and miscarriage remains completely unclear. Through screening, we identified a novel lnc-HZ12, which was significantly highly expressed in villous tissues of recurrent miscarriage (RM) patients relative to their healthy control (HC) group. Lnc-HZ12 suppressed chaperone-mediated autophagy (CMA) degradation of BBC3, promoted trophoblast cell apoptosis, and was associated with miscarriage. In mechanism, lnc-HZ12 downregulated the expression levels of chaperone molecules HSPA8 and LAMP2A in trophoblast cells. Meanwhile, lnc-HZ12 (mainly lnc-HZ12-SO2 region in F2 fragment) and HSPA8 competitively bound with the 169RVLYNL174 patch on BBC3, which prevented BBC3 from interactions with HSPA8 and impaired the formation of BBC3-HSPA8-LAMP2A complex for CMA degradation of BBC3. Thus, lnc-HZ12 upregulated the BBC3-CASP9-CASP3 pathway and induced trophoblast cell apoptosis. In villous tissues, lnc-HZ12 was highly expressed, CMA degradation of BBC3 was suppressed, and the apoptosis levels were higher in RM vs HC villous tissues, all of which were associated with miscarriage. Interestingly, knockdown of murine Bbc3 could efficiently suppress placental apoptosis and alleviate miscarriage in a mouse miscarriage model. Taken together, our results indicated that lnc-HZ12 and BBC3 played important roles in trophoblast cell apoptosis and miscarriage and might act as attractive targets for miscarriage treatment.

Transcriptomic and proteomic features of a mouse model of sperm DNA damage induced by benzo(a)pyrene

This study replicated a mouse model of sperm DNA damage induced by benzo(a)pyrene (BaP), and the transcriptomic and proteomic features of the model were examined to clarify the pathways related to BaP-induced damage to sperm DNA. Male mice in the BaP group were subjected to BaP at a dosage of 100 mg/kg/d or an equivalent quantity of saline solution in the control group for 60 days. Subsequently, the DNA fragmentation index (DFI) in sperm was assessed using a sperm chromatin structure assay (SCSA). RNA-seq and data-independent acquisition (DIA) were used to identify the mRNA and protein expression patterns in the testis. The sperm DFI significantly increased in the BaP group. Compared to the control group, the BaP group exhibited differential expression of 240 genes (referred to as DEGs) and 616 proteins (referred to as DEPs). These molecules included Aldh1a1, Cyb5r3, Fads1, Oxsm, Rcn3, and Prss45. Pathways in cancer, the PI3K-Akt signaling pathway, metabolic pathways, and the MAPK signaling pathway were the primary areas where these genes showed enrichment. BaP can damage the DNA of sperm and affect metabolism, the PI3K-Akt pathway, and pathways associated with cancer signaling.

BaP/BPDE suppresses human trophoblast cell migration/invasion and induces unexplained miscarriage by up-regulating a novel lnc-HZ11 in extracellular vesicles: An intercellular study

Extracellular vesicles (EVs) mediate the intercellular crosstalk by transferring functional cargoes. Recently, we have discovered that BaP/BPDE exposure suppresses trophoblast cell migration/invasion and induces miscarriage, which are also regulate by lncRNAs at intracelluar levels. However, the EVs-mediated intercellular regulatory mechanisms are completely unexplored. Specifically, whether EVs might transfer BPDE-induced toxic lncRNA to fresh recipient trophoblast cells and suppress their migration/invasion to further induce miscarriage is completely unknown. In this study, we find that BPDE exposure up-regulates a novel lnc-HZ11, which suppresses EGR1/NF-κB/CXCL12 pathway and migration/invasion of trophoblast cells. Intercellular studies show that EV-HZ11 (lnc-HZ11 in EVs), which is highly expressed in BPDE-exposed donor cells, suppresses EGR1/NF-κB/CXCL12 pathway and migration/invasion in recipient cells by transferring lnc-HZ11 through EVs. Analysis of villous tissues collected from UM (unexplained miscarriage) patients and HC (healthy control) group shows that the levels of BPDE-DNA adducts, lnc-HZ11 or EV-lnc-HZ11, and EGR1/NF-κB/CXCL12 pathway are all associated with miscarriage. Mouse assays show that BaP exposure up-regulates the levels of lnc-Hz11 or EV-Hz11, suppresses Egr1/Nf-κb/Cxcl12 pathway, and eventually induces miscarriage. Knockdown of lnc-Hz11 by injecting EV-AS-Hz11 could effectively alleviate miscarriage in BaP-exposed mice. Furthermore, EV-HZ11 in serum samples could well predict the risk of miscarriage. Collectively, this study not only discovers EVs-HZ11-mediated intercellular mechanisms that BaP/BPDE suppresses trophoblast cell migration/invasion and induces miscarriage but also provides new approach for treatment against unexplained miscarriage through EV-HZ11.

Defective Homologous Recombination Repair By Up-Regulating Lnc-HZ10/Ahr Loop in Human Trophoblast Cells Induced Miscarriage

Human trophoblast cells are crucial for healthy pregnancy. However, whether the defective homologous recombination (HR) repair of dsDNA break (DSB) in trophoblast cells may induce miscarriage is completely unknown. Moreover, the abundance of BRCA1 (a crucial protein for HR repair), its recruitment to DSB foci, and its epigenetic regulatory mechanisms, are also fully unexplored. In this work, it is identified that a novel lnc-HZ10, which is highly experssed in villous tissues of recurrent miscarriage (RM) vs their healthy control group, suppresses HR repair of DSB in trophoblast cell. Lnc-HZ10 and AhR (aryl hydrocarbon receptor) form a positive feedback loop. AhR acts as a transcription factor to promote lnc-HZ10 transcription. Meanwhile, lnc-HZ10 also increases AhR levels by suppressing its CUL4B-mediated ubiquitination degradation. Subsequently, AhR suppresses BRCA1 transcription; and lnc-HZ10 (mainly 1-447 nt) interacts with γ-H2AX; and thus, impairs its interactions with BRCA1. BPDE exposure may trigger this loop to suppress HR repair in trophoblast cells, possibly inducing miscarriage. Knockdown of murine Ahr efficiently recovers HR repair in placental tissues and alleviates miscarriage in a mouse miscarriage model. Therefore, it is suggested that AhR/lnc-HZ10/BRCA1 axis may be a promising target for alleviation of unexplained miscarriage.

TBX3 reciprocally controls key trophoblast lineage decisions in villi during human placenta development in the first trimester

Human trophoblastic lineage development is intertwined with placental development and pregnancy outcomes, but the regulatory mechanisms underpinning this process remain inadequately understood. In this study, based on single-nuclei RNA sequencing (snRNA-seq) analysis of the human early maternal-fetal interface, we compared the gene expression pattern of trophoblast at different developmental stages. Our findings reveal a predominant upregulation of TBX3 during the transition from villous cytotrophoblast (VCT) to syncytiotrophoblast (SCT), but downregulation of TBX3 as VCT progresses into extravillous trophoblast cells (EVT). Immunofluorescence analysis verified the primary expression of TBX3 in SCT, partial expression in MKi67-positive VCT, and absence in HLA-G-positive EVT, consistent with our snRNA-seq results. Using immortalized trophoblastic cell lines (BeWo and HTR8/SVneo) and human primary trophoblast stem cells (hTSCs), we observed that TBX3 knockdown impedes SCT formation through RAS-MAPK signaling, while TBX3 overexpression disrupts the cytoskeleton structure of EVT and hinders EVT differentiation by suppressing FAK signaling. In conclusion, our study suggests that the spatiotemporal expression of TBX3 plays a critical role in regulating trophoblastic lineage development via distinct signaling pathways. This underscores TBX3 as a key determinant during hemochorial placental development.

Hypoxia causes trophoblast cell ferroptosis to induce miscarriage through lnc-HZ06/HIF1α-SUMO/NCOA4 axis

Defects of human trophoblast cells may induce miscarriage (abnormal early embryo loss), which is generally regulated by lncRNAs. Ferroptosis is a newly identified iron-dependent programmed cell death. Hypoxia is an important and unavoidable feature in mammalian cells. However, whether hypoxia might induce trophoblast cell ferroptosis and then induce miscarriage, as well as regulated by a lncRNA, was completely unknown. In this work, we discovered at the first time that hypoxia could result in ferroptosis of human trophoblast cells and then induce miscarriage. We also identified a novel lncRNA (lnc-HZ06) that simultaneously regulated hypoxia (indicated by HIF1α protein), ferroptosis, and miscarriage. In mechanism, HIF1α-SUMO, instead of HIF1α itself, primarily acted as a transcription factor to promote the transcription of NCOA4 (ferroptosis indicator) in hypoxic trophoblast cells. Lnc-HZ06 promoted the SUMOylation of HIF1α by suppressing SENP1-mediated deSUMOylation. HIF1α-SUMO also acted as a transcription factor to promote lnc-HZ06 transcription. Thus, both lnc-HZ06 and HIF1α-SUMO formed a positive auto-regulatory feedback loop. This loop was up-regulated in hypoxic trophoblast cells, in RM villous tissues, and in placental tissues of hypoxia-treated mice, which further induced ferroptosis and miscarriage by up-regulating HIF1α-SUMO-mediated NCOA4 transcription. Furthermore, knockdown of either murine lnc-hz06 or Ncoa4 could efficiently suppress ferroptosis and alleviate miscarriage in hypoxic mouse model. Taken together, this study provided new insights in understanding the regulatory roles of lnc-HZ06/HIF1α-SUMO/NCOA4 axis among hypoxia, ferroptosis, and miscarriage, and also offered an effective approach for treatment against miscarriage.

CircRNA hsa_circ_0000043 acts as a miR-4492 sponge to promote lung cancer progression via BDNF and STAT3 expression regulation in anti-benzo[a]pyrene-trans-7,8-dihydrodiol-9,10-epoxide-transformed 16HBE cells

Increasing evidence shows that circular RNA (circRNA) plays an important role in the progression of lung cancer. In this study, we found that has_circ_0000043 was highly expressed in 16HBE-T human bronchial epithelial cells that were malignantly transformed by benzo[a]pyrene-trans-7,8-diol-9,10-epoxide via circRNA microarray. We verified that hsa_circ_0000043 was also significantly overexpressed in lung cancer cell lines and tissues. Moreover, hsa_circ_0000043 overexpression was positively correlated with poor clinicopathological parameters, such as tumor-node metastasis stage, distant metastasis, lymph-node metastasis, and overall survival. In vitro assays revealed that hsa_circ_0000043 inhibition suppressed 16HBE-T cell proliferation, migration, and invasion. Furthermore, hsa_circ_0000043 inhibition suppressed tumor growth in a mouse xenograft model. We discovered that hsa_circ_0000043 binds with miR-4492, acting as a miR-4492 sponge. Decreased miR-4492 expression was also associated with poor clinicopathological parameters. Thus, hsa_circ_0000043 was shown to contribute to the proliferation, malignant transformation ability, migration, and invasion of 16HBE-T cells via miR-4492 sponging and BDNF and STAT3 involvement.

Effects of polycyclic aromatic hydrocarbons (PAHs) on pregnancy, placenta, and placental trophoblasts

Polycyclic aromatic hydrocarbons (PAHs) are a group of persistent organic pollutants that are carcinogenic, mutagenic, endocrine-toxic, and immunotoxic. PAHs can be found in maternal and fetal blood and in the placenta during pregnancy. They may thus affect placental and fetal development. Therefore, the exposure levels and toxic effects of PAHs in the placenta deserve further study and discussion. This review aims to summarize current knowledge on the effects of PAHs and their metabolites on pregnancy and birth outcomes and on placental trophoblast cells. A growing number of epidemiological studies detected PAH-DNA adducts as well as the 16 high-priority PAHs in the human placenta and showed that placental PAH exposure is associated with adverse fetal outcomes. Trophoblasts are important cells in the placenta and are involved in placental development and function. In vitro studies have shown that exposure to either PAH mixtures, benzo(a)pyrene (BaP) or BaP metabolite benzo(a)pyrene-7,8-dihydrodiol-9,10-epoxide (BPDE) affected trophoblast cell viability, differentiation, migration, and invasion through various signaling pathways. Furthermore, similar effects of BPDE on trophoblast cells could also be observed in BaP-treated mouse models and were related to miscarriage. Although the current data show that PAHs may affect placental trophoblast cells and pregnancy outcomes, further studies (population studies, in vitro studies, and animal studies) are necessary to show the specific effects of different PAHs on placental trophoblasts and pregnancy outcomes.

BPDE exposure promotes trophoblast cell pyroptosis and induces miscarriage by up-regulating lnc-HZ14/ZBP1/NLRP3 axis

Environmental Benzo(a)pyrene (BaP) and its ultimate metabolite BPDE (benzo(a)pyrene-7,8-dihydrodiol-9,10-epoxide) are typical persistent organic pollutants and endocrine disrupting chemicals. BaP/BPDE exposure might cause human trophoblast cell dysfunctions and induce miscarriage. However, the underlying mechanisms remain largely elusive. In this study, we found that BPDE exposure induced human trophoblast cell pyroptosis by up-regulating NLRP3/Caspase1/GSDMD pathway. We also identified that lnc-HZ14 was highly expressed in BPDE-exposed trophoblast cells and in recurrent miscarriage (RM) vs healthy control (HC) villous tissues. Lnc-HZ14 promoted trophoblast cell pyroptosis by promoting IRF1-mediated ZBP1 transcription, increasing METTL3-mediated m6A methylation on NLRP3 mRNA and its stability, and also enhancing ZBP1/NLRP3 protein interactions. Knockdown of lnc-HZ14/ZBP1/NLRP3 axis could efficiently alleviate BPDE-induced trophoblast cell pyroptosis. Higher level of pyroptosis, as indicated by the up-regulation of lnc-HZ14/ZBP1/NLRP3 axis, was found in RM vs HC villous tissues. In BaP-exposed mouse model, BaP exposure induced placental tissue pyroptosis and miscarriage by up-regulating murine Zbp1/Nlrp3 axis, and knockdown of Nlrp3 could efficiently reduce placenta pyroptosis and alleviate BaP-induced mouse miscarriage. Serum IL-1β protein level might act as a promising indicator to predict the risk of miscarriage. These findings provided new insights into BaP/BPDE-induced trophoblast cell pyroptosis and miscarriage and might be helpful for further assessment of the toxicological effects of BaP/BPDE on the female reproduction.

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

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, 1.0, or 1.5μM 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 (n=15) group and their matched healthy control (HC, n=15) 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 0.2mg/kg B(a)P-induced mouse miscarriage model (each n=6), 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, providing new insights in understanding the causes and mechanisms of unexplained miscarriage. https://doi.org/10.1289/EHP10477.

Roles of GFPT2 Expression Levels on the Prognosis and Tumor Microenvironment of Colon Cancer

Background

Recently, increasing evidence has suggested that Glutamine-fructose-6-phosphate transaminase 2 (GFPT2) is related to carcinogenesis. However, the potential roles of GFPT2 in colon cancer still need to be fully investigated.

Methods

We examined the protein levels of GFPT2 by immunohistochemistry (IHC) in tissues collected from 83 patients with colon cancer. We further detected GFBPT2 protein levels by Western Blot assay. We checked the relationship between GFPT2 expression levels and overall survival (OS), stromal and immune scores and immune components from The Cancer Gene Atlas (TCGA) database. GFBP2-related pathways were validated in the Cancer Cell Line Encyclopedia (CCLE) database. Expression of GFPT2 in single cell subpopulations was calculated from The Tumor Immune Single Cell Center (TISCH). The levels of GFPT2 and drug sensitivity data were performed from CellMiner dataset.

Results

GFPT2 was highly expressed and correlated with poor pathological features in 83 colon cancer patients. Moreover, increased GFPT2 expression was significantly associated with poorer OS in 329 colon adenocarcinoma (COAD) patients. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed the differentially expressed genes of GFPT2 were mostly enriched in focal adhesion, ECM receptor interaction, JAK/STAT signaling pathway and immune related pathways. In addition, GFPT2 expression was correlated with the tumor microenvironment (TME). GFPT2 expression was linked to cancer-associated fibroblasts (CAFs)-associated factors and epithelial-mesenchymal transition (EMT)-related factors. GFPT2 was positively correlated with immunosuppressive cells and regulated immunosuppressive factors and T-cell exhaustion. Finally, our data suggested that the expression of GFPT2 may be a judgment of the sensitivity of a certain class of drugs.

Conclusions

Our work reveals the roles of GFPT2 in tumorigenesis, particularly in immune response, TME and drug resistance, which are crucial for the development of customized cancer therapies.