Aggressive vertebral hemangiomas contain no adipose tissue resulting in thoracic spine kyphosis: A case report.

RATIONALE: Aggressive vertebral hemangiomas (AVHs) destroy continuous vertebral bodies and intervertebral discs and resulting in spinal kyphosis is extremely rare. The very aggressive behavior was attributable to its significant vascular component and contained no adipose tissue. PATIENT CONCERNS: We report a case of thoracic spine kyphosis of AVHs with multiple vertebral bodies and intervertebral disc destruction in a 45-year-old woman. DIAGNOSES: Based on the imaging studies, the patient underwent surgical removal of this lesion and spinal reconstruction. Histopathology consistent with vertebral hemangioma and contained no adipose. INTERVENTIONS: The patient underwent surgical removal of the lesion and spinal reconstruction. After subperiosteal dissection of the paraspinal muscles and exposure of the laminae, the laminae of the T5-7 vertebrae were removed and exposing the lesion. The lesion was soft and showed cystic changes, completely curetted and autogenous bone was implanted. Vertebroplasty was performed through T3-T9 pedicles bilaterally. Pedicle screw fixation was performed for segmental fixation and fusion. OUTCOMES: After 9 days of operation, the incision healed cleanly and free of pain. She was discharged in good general condition. The patient remained asymptomatic after follow-up 6 months of postoperative. LESSONS: AVHs destroy multiple vertebral bodies and intervertebral discs and resulting in spinal kyphosis is extremely rare.

Functional antagonism between ΔNp63α and GCM1 regulates human trophoblast stemness and differentiation.

The combination of EGF, CHIR99021, A83-01, SB431542, VPA, and Y27632 (EGF/CASVY) facilitates the derivation of trophoblast stem (TS) cells from human blastocysts and first-trimester, but not term, cytotrophoblasts. The mechanism underlying this chemical induction of TS cells remains elusive. Here we demonstrate that the induction efficiency of cytotrophoblast is determined by functional antagonism of the placental transcription factor GCM1 and the stemness regulator ΔNp63α. ΔNp63α reduces GCM1 transcriptional activity, whereas GCM1 inhibits ΔNp63α oligomerization and autoregulation. EGF/CASVY cocktail activates ΔNp63α, thereby partially inhibiting GCM1 activity and reverting term cytotrophoblasts into stem cells. By applying hypoxia condition, we can further reduce GCM1 activity and successfully induce term cytotrophoblasts into TS cells. Consequently, we identify mitochondrial creatine kinase 1 (CKMT1) as a key GCM1 target crucial for syncytiotrophoblast differentiation and reveal decreased CKMT1 expression in preeclampsia. Our study delineates the molecular underpinnings of trophoblast stemness and differentiation and an efficient method to establish TS cells from term placentas.

SFRP3 negatively regulates placental extravillous trophoblast cell migration mediated by the GCM1-WNT10B-FZD7 axis.

Migration of placental extravillous trophoblast (EVT) cells into uterine decidua facilitates the establishment of blood circulation between mother and fetus and is modulated by EVT-decidual cell interaction. Poor or excessive EVT migration is associated with pregnancy complications such as preeclampsia or placenta accreta. Glial cells missing 1 (GCM1) transcription factor is essential for placental development, and decreased GCM1 activity is detected in preeclampsia. To study whether GCM1 regulates trophoblast cell migration, here we showed that GCM1 promotes BeWo and JAR trophoblast cell migration through a novel target gene, WNT10B. Moreover, WNT10B signaling stimulated cytoskeletal remodeling via Rac1 and frizzled 7 (FZD7) was identified as the cognate receptor for WNT10B to up-regulate cell migration. We further showed that secreted frizzled-related protein 3 (SFRP3) is expressed in uterine decidual cells by immunohistochemistry and that SFRP3 expression in telomerase-transformed human endometrial stromal cells (T-HESCs) is elevated under decidualization stimuli and further enhanced by bone morphogenetic protein 2 via SMAD1. SFRP3 blocked the interaction between FZD7 and WNT10B to decrease BeWo cell migration, which corroborated the elevated BeWo cell migration when cocultured with decidualized and SFRP3-knockdown T-HESC monolayer. Our results suggest that GCM1 up-regulates EVT cell migration through WNT10B and FZD7, which is negatively modulated by decidual SFRP3.-Wang, L.-J., Lo, H.-F., Lin, C.-F., Ng, P.-S., Wu, Y.-H., Lee, Y.-S., Cheong, M.-L., Chen, H. SFRP3 negatively regulates placental extravillous trophoblast cell migration mediated by the GCM1-WNT10B-FZD7 axis.

A Positive Feedback Loop between Glial Cells Missing 1 and Human Chorionic Gonadotropin (hCG) Regulates Placental hCGß Expression and Cell Differentiation.

Human chorionic gonadotropin (hCG) is composed of a common α subunit and a placenta-specific ß subunit. Importantly, hCG is highly expressed in the differentiated and multinucleated syncytiotrophoblast, which is formed via trophoblast cell fusion and stimulated by cyclic AMP (cAMP). Although the ubiquitous activating protein 2 (AP2) transcription factors TFAP2A and TFAP2C may regulate hCGß expression, it remains unclear how cAMP stimulates placenta-specific hCGß gene expression and trophoblastic differentiation. Here we demonstrated that the placental transcription factor glial cells missing 1 (GCM1) binds to a highly conserved promoter region in all six hCGß paralogues by chromatin immunoprecipitation-on-chip (ChIP-chip) analyses. We further showed that cAMP stimulates GCM1 and the CBP coactivator to activate the hCGß promoter through a GCM1-binding site (GBS1), which also constitutes a previously identified AP2 site. Given that TFAP2C may compete with GCM1 for GBS1, cAMP enhances the association between the hCGß promoter and GCM1 but not TFAP2C. Indeed, the hCG-cAMP-protein kinase A (PKA) signaling pathway also stimulates Ser269 and Ser275 phosphorylation of GCM1, which recruits CBP to mediate GCM1 acetylation and stabilization. Consequently, hCG stimulates the expression of GCM1 target genes, including the fusogenic protein syncytin-1, to promote placental cell fusion. Our study reveals a positive feedback loop between GCM1 and hCG regulating placental hCGß expression and cell differentiation.

Cyclin D1 acts as a barrier to pluripotent reprogramming by promoting neural progenitor fate commitment.

A short G1 phase is a characteristic feature of the cell cycle structure of pluripotent cells, and is reestablished during Yamanaka factor-mediated pluripotent reprogramming. How cell cycle control is adjusted to meet the requirements of pluripotent cell fate commitment during reprogramming is less well understood. Elevated levels of cyclin D1 were initially found to impair pluripotency maintenance. The current work further identified Cyclin D1 to be capable of transcriptionally upregulating Pax6, which promoted reprogramming cells to commit to a neural progenitor fate rather than a pluripotent cell fate. These findings explain the importance of reestablishment of G1-phase restriction in pluripotent reprogramming.

A role for interleukin-17A in modulating intracellular survival of Mycobacterium bovis bacillus Calmette-Guérin in murine macrophages.

Interleukin 17A IL-17A is a crucial immunomodulator in various chronic immunological diseases including rheumatoid arthritis and inflammatory bowel disease. The cytokine has also been demonstrated to control the pathogenesis of the Mycobacterium tuberculosis by dysregulating production of cytokines and chemokines and promoting granuloma formation. Whether IL-17A regulates innate defence mechanisms of macrophages in response to mycobacterial infection remains to be elucidated. In the current report, we investigated the effects of IL-17A on modulating the intracellular survival of Mycobacterium bovis bacillus Calmette-Guérin (BCG) in RAW264.7 murine macrophages. We observed that IL-17A pre-treatment for 24 hr was able to synergistically enhance BCG-induced nitric oxide (NO) production and inducible nitric oxide synthase expression in dose- and time-dependent manners. We further delineated the mechanisms involved in this synergistic reaction. IL-17A was found to specifically enhanced BCG-induced phosphorylation of Jun N-terminal kinase (JNK), but not of extracellular signal-regulated kinase 1/2 and p38 mitogen-activated protein kinase. By using a specific JNK inhibitor (SP600125), we found that the production of NO in BCG-infected macrophages was significantly suppressed. Taken together, we confirmed the involvement of the JNK pathway in IL-17A-enhanced NO production in BCG-infected macrophages. We further demonstrated that IL-17A significantly enhanced the clearance of intracellular BCG by macrophages through an NO-dependent killing mechanism. In conclusion, our study revealed an anti-mycobacterial role of IL-17A through priming the macrophages to produce NO in response to mycobacterial infection.

High-temperature requirement protein A4 (HtrA4) suppresses the fusogenic activity of syncytin-1 and promotes trophoblast invasion.

Cell-cell fusion and cell invasion are essential for placental development. Human cytotrophoblasts in the chorionic villi may undergo cell-cell fusion to form syncytiotrophoblasts to facilitate nutrient-gas exchange or differentiate into extravillous trophoblasts (EVTs) to facilitate maternal-fetal circulation. The placental transcription factor glial cells missing 1 (GCM1) regulates syncytin-1 and -2 expression to mediate trophoblast fusion. Interestingly, GCM1 and syncytin-1 are also expressed in EVTs with unknown physiological functions. In this study, we performed chromatin immunoprecipitation-on-chip (ChIP-chip) analysis and identified the gene for high-temperature requirement protein A4 (HtrA4) as a GCM1 target gene, which encodes a serine protease facilitating cleavage of fibronectin and invasion of placental cells. Importantly, HtrA4 is immunolocalized in EVTs at the maternal-fetal interface, and its expression is decreased by hypoxia and in preeclampsia, a pregnancy complication associated with placental hypoxia and shallow trophoblast invasion. We further demonstrate that HtrA4 interacts with syncytin-1 and suppresses cell-cell fusion. Therefore, HtrA4 may be crucial for EVT differentiation by playing a dual role in prevention of cell-cell fusion of EVTs and promotion of their invasion into the uterus. Our study reveals a novel function of GCM1 and HtrA4 in regulation of trophoblast invasion and that abnormal HrtA4 expression may contribute to shallow trophoblast invasion in preeclampsia.

GCM1 regulation of the expression of syncytin 2 and its cognate receptor MFSD2A in human placenta.

Syncytin 2 is a newly identified placental membrane protein with fusogenic and immunosuppressive activities. Major facilitator superfamily domain containing 2A (MFSD2A) is the cognate receptor for syncytin 2-mediated cell-cell fusion. Both syncytin 2 and MFSD2A are highly expressed in placenta. In this study to understand the regulation of syncytin 2 and MFSD2A expression in placenta, we found that syncytin 2 gene is epigenetically silenced in nonplacental cells by cytosine-phosphate-guanine (CpG) dinucleotide methylation and that expression of syncytin 2 and MFSD2A genes are regulated by the placental transcription factor GCM1 in placental cells. Functional GCM1-binding sites were identified in syncytin 2 and MFSD2A promoters based on electrophoretic mobility shift assay and chromatin immunoprecipitation assay. Because GCM1 activity is decreased in hypoxic placental cells, we further confirmed that expression of MFSD2A is downregulated in hypoxic BeWo choriocarcinoma cells. Interestingly, ectopic expression of GCM1 activated syncytin 2 and MFSD2A expression in MCF-7 breast cancer cells and facilitated MCF-7 cell fusion. The expression of syncytin 2 in MCF-7 cells was partly attributed to CpG demethylation in the syncytin 2 promoter in the presence of GCM1. Our results suggest that GCM1 is a critical factor in controlling placental cell fusion through transcriptional regulation of syncytin 2 and MFSD2A gene expression in placenta. In addition, GCM1 may also play an important role in the epigenetic regulation of syncytin 2 gene expression.

Mechanism of hypoxia-induced GCM1 degradation: implications for the pathogenesis of preeclampsia.

Preeclampsia is a major pregnancy-specific disorder affecting 5-7% of pregnancies worldwide. Although hypoxia caused by incomplete trophoblast invasion and impaired spiral arterial remodeling is thought to be a major cause of preeclampsia, how hypoxia affects placental development remains uncertain. GCM1 (glial cells missing homolog 1) is a transcription factor critical for placental development. In preeclampsia, GCM1 and its target genes syncytin 1 and placental growth factor, important for syncytiotrophoblast formation and placental vasculogenesis, are all decreased. Here we present evidence that GCM1 is a major target of hypoxia associated with preeclampsia. We show that hypoxia triggers GCM1 degradation by suppressing the phosphatidylinositol 3-kinase-Akt signaling pathway, leading to GSK-3beta activation. Activated GSK-3beta phosphorylates GCM1 on Ser322, which in turn recruits the F-box protein FBW2, leading to GCM1 ubiquitination and degradation. Importantly, the GSK-3beta inhibitor LiCl prevented hypoxia-induced GCM1 degradation. Our study identifies a molecular basis for the disrupted GCM1 transcription network in preeclampsia and provides a potential avenue for therapeutic intervention.