CTNNB1 mutation-driven hybrid tumor: desmoid fibromatosis with an unusual associated epithelioid component arising in association with a neuromuscular choristoma.

CTNNB1 mutations play important roles in the development of soft tissue tumors, such as desmoid fibromatosis (DF), sinonasal tract angiofibroma, sinonasal glomangiopericytoma, intranodal palisaded myofibroblastoma, neuromuscular choristoma (NMC), and the recently reported pseudoendocrine sarcoma. Here, we report a unique hybrid soft tissue tumor with classic DF, unusual epithelioid component, and NMC in a 23-year-old female. The classic DF and NMC and the unusual epithelioid component and NMC were locally intermixed and closely related to each other. Immunohistochemically, the DF, unusual epithelioid component, and NMC exhibited nuclear positivity for ß-catenin to varying degrees. More critically, all of the above components harbored identical CTNNB1 p.Ser45Pro missense mutations. To the best of our knowledge, this is the only reported CTNNB1 mutation-driven hybrid tumor with DF, unusual epithelioid component, and NMC. The present case further confirmed that CTNNB1-mutational soft tissue tumors are highly heterogeneous, but the morphological spectrum is wide and consecutive.

Single-cell analysis of endometriosis reveals a coordinated transcriptional programme driving immunotolerance and angiogenesis across eutopic and ectopic tissues.

Endometriosis is characterized by the growth of endometrial-like tissue outside the uterus. It affects many women during their reproductive age, causing years of pelvic pain and potential infertility. Its pathophysiology remains largely unknown, which limits early diagnosis and treatment. We characterized peritoneal and ovarian lesions at single-cell transcriptome resolution and compared them to matched eutopic endometrium, unaffected endometrium and organoids derived from these tissues, generating data on over 122,000 cells across 14 individuals. We spatially localized many of the cell types using imaging mass cytometry. We identify a perivascular mural cell specific to the peritoneal lesions, with dual roles in angiogenesis promotion and immune cell trafficking. We define an immunotolerant peritoneal niche, fundamental differences in eutopic endometrium and between lesion microenvironments and an unreported progenitor-like epithelial cell subpopulation. Altogether, this study provides a holistic view of the endometriosis microenvironment that represents a comprehensive cell atlas of the disease in individuals undergoing hormonal treatment, providing essential information for future therapeutics and diagnostics.

Neuromuscular Choristoma: Report of Five Cases With CTNNB1 Sequencing.

Neuromuscular choristoma (NMC) are lesions of the peripheral nervous system characterized by an admixture of skeletal muscle fibers and nerves fascicles that are frequently associated with desmoid fibromatosis (DF). Mutations in CTNNB1, the gene for ß-catenin protein, are common in DF and related to its pathogenesis. They are restricted to exon 3, with 3 point mutations: T41A, S45F, and S45P. To understand the pathogenesis of NMC, we tested CTNNB1 status in 5 cases of NMC whether or not they were associated with DF. The screening of mutations in CTNNB1 gene was based on amplicon deep sequencing using the ION Proton platform. Three patients had the S45F mutation; in 2 the mutation was common to both lesions and in one the DF was wild type while the NMC had the S45F mutation. One patient had a T41A mutation in the NMC and no associated DF. In the last patient, the DF lesion had a T41A mutation; there was no lesion with the S45P mutation. The presence of similar CTNNB1 mutations in NMC/DF-associated lesions and sporadic DF reinforces the relationship between both lesions and points to a common pathogenic mechanism.

Frequent CTNNB1 p.S45 Mutations and Aggressive Clinical Behavior in Neuromuscular Choristoma-Associated Fibromatosis.

BACKGROUND: Neuromuscular choristoma (NMC) is a peripheral nerve malformation frequently associated with a fibromatosis (NMC-DTF) that mimics sporadic desmoid-type fibromatosis (DTF). Sporadic DTF is often managed conservatively but its clinical behavior varies. CTNNB1 mutational subtypes in sporadic DTF have prognostic value. We have previously identified CTNNB1 mutations in NMC, and 3 paired NMC-DTF but the clinical behavior of NMC-DTF is poorly understood. OBJECTIVE: To evaluate patients with NMC-DTF to determine (1) CTNNB1 mutational subtypes in NMC-DTF, and (2) associated clinical behavior and response to treatment. METHODS: Retrospective review of clinical, imaging, and pathologic features of patients with NMC and NMC-DTF, and molecular testing for CTNNB1 mutations. RESULTS: Among 7 patients with NMC of the sciatic nerve (median age: 18 yr), NMC-DTF (mean size 10.7 cm) developed shortly following NMC biopsy (N = 5) or spontaneously (N = 2): 6 NMC-DTF had CTNNB1 p.S45X mutations and 1 NMC-DTF had a p.T41A mutation. All patients with CTNNB1-p.S45-mutated NMC-DTF developed local progression after wide local excision or active surveillance, including one distal metachronous NMC-DTF. No patient had spontaneous disease stabilization. Following adjuvant radiation or systemic therapy, disease stabilization was achieved in 4 (of 6) patients. One patient progressed on sorafenib treatment. CONCLUSION: NMC-DTF frequently contain CTNNB1 p.S45 mutations, behave aggressively, and require adjuvant therapies for disease stabilization. We now use imaging alone to diagnose NMC, and routinely surveille the NMC-affected nerve segment to identify early NMC-DTF. In contrast to sporadic DTF, earlier adoption of systemic therapeutic strategies may be required for optimal disease management of NMC-DTF.

Epigenetic mechanisms involved in intrauterine growth restriction and aberrant kidney development and function.

Intrauterine growth restriction (IUGR) due to uteroplacental insufficiency results in a placenta that is unable to provide adequate nutrients and oxygen to the fetus. These growth-restricted babies have an increased risk of hypertension and chronic kidney disease later in life. In rats, both male and female growth-restricted offspring have nephron deficits but only males develop kidney dysfunction and high blood pressure. In addition, there is transgenerational transmission of nephron deficits and hypertension risk. Therefore, epigenetic mechanisms may explain the sex-specific programming and multigenerational transmission of IUGR-related phenotypes. Expression of DNA methyltransferases (Dnmt1and Dnmt3a) and imprinted genes (Peg3, Snrpn, Kcnq1, and Cdkn1c) were investigated in kidney tissues of sham and IUGR rats in F1 (embryonic day 20 (E20) and postnatal day 1 (PN1)) and F2 (6 and 12 months of age, paternal and maternal lines) generations (n = 6-13/group). In comparison to sham offspring, F1 IUGR rats had a 19% decrease in Dnmt3a expression at E20 (P < 0.05), with decreased Cdkn1c (19%, P < 0.05) and increased Kcnq1 (1.6-fold, P < 0.01) at PN1. There was a sex-specific difference in Cdkn1c and Snrpn expression at E20, with 29% and 34% higher expression in IUGR males compared to females, respectively (P < 0.05). Peg3 sex-specific expression was lost in the F2 IUGR offspring, only in the maternal line. These findings suggest that epigenetic mechanisms may be altered in renal embryonic and/or fetal development in growth-restricted offspring, which could alter kidney function, predisposing these offspring to kidney disease later in life.

MicroRNA­202 inhibits endometrial stromal cell migration and invasion by suppressing the K­Ras/Raf1/MEK/ERK signaling pathway.

The enhanced migratory ability of endometrial stromal cells (ESCs) is a key factor in the formation of functional endometrium­like tissues outside the uterine cavity during endometriosis (EMS). Although accumulating evidence has suggested the importance of microRNAs (miRNAs) in the pathogenesis of EMS, the role of particular miRNAs in the invasiveness of ESCs remain poorly understood. In the present study, the function of miRNAs in the invasiveness of ESCs, along with the associated underlying mechanism involved, were investigated. Initially, the expression patterns of miRNAs in the ectopic and eutopic endometrium isolated from patients with EMS were analyzed using microarray. MicroRNA­202­5p (miR­202) was selected for further study due to its previously reported suppressive effects on the invasion in various types of cancers. The expression of miR­202 and K­Ras in eutopic and ectopic endometrioma tissues were detected using reverse transcription­quantitative PCR, immunohistochemistry and western blotting. The migration and invasion ability of ESCs was determined using wound healing and Transwell invasion assays, respectively. Compared with that from healthy individuals, miR­202 expression was demonstrated to be lower in the eutopic endometrium from patients with EMS, which was even lower in ectopic endometrium. Functional experiments in primary ESCs revealed that enhanced miR­202 expression suppressed the cell invasion and migration abilities, which was also accompanied with increased E­cadherin and reduced N­cadherin expression in ESCs, suggesting its potentially suppressive role in epithelial­mesenchymal transition. K­Ras is a well­known regulator of the ERK signaling pathway that was shown to be directly targeted and negatively regulated by miR­202. In addition, K­Ras expression was found to be upregulated in the ectopic endometrium, where it correlated negatively with that of miR­202. Knocking down K­Ras expression mimicked the anti­invasive effects of miR­202 overexpression on ESCs, whilst K­Ras overexpression attenuated the inhibitory role of miR­202 overexpression in ESC invasion. The K­Ras/Raf1/MEK/ERK signaling pathway was also blocked by miR­202 overexpression. These findings suggested that miR­202 inhibited ESC migration and invasion by inhibiting the K­Ras/Raf1/MEK/ERK signaling pathway, rendering miR­202 a candidate for being a therapeutic target for EMS.

Mouse model for endometriosis is characterized by proliferation and inflammation but not epithelial-to-mesenchymal transition and fibrosis.

Endometriosis is a common disorder of unknown etiology, and non-surgical therapies are still a challenge. To understand the pathogenesis and preclinical testing of drugs for endometriosis, animal models are highly desirous. Herein, we carried out longitudinal characterization of a mouse model for endometriosis where uterine tissue was transplanted onto the intestinal mesentery. During the course of lesion development from day 15 to 60 post-induction, the ectopic endometrium became pale, fluid-filled and the animals developed peritoneal adhesions. Most lesions resembled a well-differentiated type of endometriosis and ~13% of animals had mixed type of lesions. There was extensive stromal compaction in the ectopic tissue. During the progression of endometriosis, there was increased proliferation of epithelial and stromal cells as evident by PCNA staining. Cyp19a1 (aromatase) mRNA was detected in the ectopic lesions on day 15 and 30 post-induction of endometriosis, by day 60 the expression was reduced. As compared to the control endometrium, the mRNA levels of Esr1 progressively reduced while the levels of inflammation associated genes (Esr2, Ifng, Tnf and Il1b) increased in the ectopic lesions. Infiltration of macrophages and polymorphonuclear leucocytes was also observed in the ectopic lesions indicative of inflammation. As compared to control, there was no change in levels of Cytokeratin and E-cadherin in the epithelial cells of ectopic endometrium. We did not observe excessive collagen deposition or α -SMA positive myofibroblasts in the stroma of the ectopic endometrium. Thus, epithelial-to-mesenchymal transition and fibrosis are not detected in the mouse model of endometriosis. Our results show that the mouse model of endometriosis mimics some but not all the features of human endometriosis.

Chondroid and Osseous Metaplasia of the Central Fibrous Body in Adolescent Hearts with Mutations in TNNI3 and TNNT2 genes.

The histological spectrum of the central fibrous body (CFB) of the heart, particularly in humans, is not fully characterized. Herein, we describe the presence of cartilage and bone within the CFB of 2 explanted heart specimens from patients with known mutation-driven cardiomyopathy involving the TNNI3 and TNNT2 genes, review the existing literature on the identified variants particularly TNNI3 (p.Asn185Thrfs*14) and TNNT2 (p.Arg141Trp), and provide insights into the plausible nature of such histopathological observation based on animal studies and the few reported cases in humans.

Challenges in the diagnostics and treatment of ectopic ameloblastic carcinoma: a case report.

Ameloblastic carcinoma (AC) is a rare and aggressive malignant epithelial odontogenic tumor, most commonly located in the mandible or maxilla. An extremely rare extragnathic localization of AC with no connection to the jaws, ectopic ameloblastic carcinoma (EAC), has so far been described only three times. This report presents a 64-year-old male with skull base ameloblastic carcinoma and offers a review of diagnostic and treatment challenges related to EAC. Because of its rarity and histological similarity to other tumors, EAC is often misdiagnosed. This is why we established a pathohistological and immunohistochemical profile of EAC that differentiates it from histologically similar tumors. The most frequently used EAC treatment is radical surgical resection, but the majority of reviewed reports described local recurrence. Taking into consideration new scientific discoveries on the molecular pathogenesis of ameloblastoma, we are the first to have performed BRAF mutation analysis in an EAC patient. BRAF inhibitors offer promising results in the treatment of BRAF-positive ameloblastomas and should continue to be researched in AC and EAC patients. Finally, EAC should be considered in differential diagnosis of head and neck tumors outside the jaws.

Identification of Recurrent TERT Promoter Mutations in Intrathyroid Thymic Carcinomas.

Intrathyroid thymic carcinoma (ITTC) is a rare malignant neoplasm considered to be a eutopic thymic carcinoma (TC) arising ectopically in the thyroid. Histopathologically, ITTC resembles squamous cell carcinoma of the thymus with positive TC markers such as CD5 and c-KIT. Despite these similar histological findings, ITTC is clinically less aggressive than TC. In this study, we compared clinical, histological, and genetic characteristics of ITTCs and TCs. We collected 9 ITTCs and 8 TCs with their clinicopathological profiles. Immunohistochemistry for CD5, p63, CD117/c-KIT, Ki-67, p53, TTF-1, thyroglobulin, PAX8, EGFR, and PD-L1/CD274 plus in situ hybridization for EBER was performed. We further investigated mutation status of KIT, EGFR, BRAF, and TERT promoter using Sanger sequencing. In our study, ITTCs affected significantly younger patients than TCs. After a mean follow-up of 86 months, all patients with ITTC were alive, while two patients with TC had died. Immunohistochemistry showed ITTCs and TCs had a similar immunophenotype except for EGFR and p53. Genetic analysis did not identify KIT or BRAF mutations in any ITTCs or TCs. EGFR mutations were positive in 11% (1/9) of ITTCs and 25% (2/8) of TCs. Notably, TERT promoter C228T mutation was identified in 22% (2/9) of ITTCs but none of the TCs. There were no significant differences in age, tumor size, or sex between TERT-mutated and TERT-wild-type ITTCs. Collectively, ITTC and TC have similar histopathologic and immunophenotypic features but different clinical outcomes. Recurrent TERT promoter mutation may be a key event related to cancer progression in ITTCs and warrants further investigation.

Majority of cerebrospinal fluid-contacting neurons in the spinal cord of C57Bl/6N mice is present in ectopic position unlike in other studied experimental mice strains and mammalian species.

Cerebrospinal fluid contacting neurons (CSF-cNs) represent a specific class of neurons located in close vicinity of brain ventricles and central canal. In contrast with knowledge gained from other vertebrate species, we found that vast majority of CSF-cNs in the spinal cord of C57Bl/6N mice is located in ectopic distal ventral position. However, we found that small number of ectopic CSF-cNs is present also in spinal cord of other investigated experimental mice strains (C57Bl/6J, Balb/C) and mammalian species (Wistar rats, New Zealand White rabbits). Similarly, as the proximal populations, ectopic CSF-cNs retain PKD2L1-immunoreactivity and synaptic contacts with other neurons. On the other side, they show rather multipolar morphology lacking thick dendrite contacting central canal lumen. Ectopic CSF-cNs in the spinal cord of C57Bl/6N mice emerge during whole period devoted to production of CSF-cNs and reach their ventral destinations during first postnatal weeks. In order to identify major gene, whose impairment could trigger translocation of CSF-cNs outside the central canal area, we took advantage of close consanguinity of C57Bl/6J substrain with normal CSF-cN distribution and C57Bl/6N substrain with majority of CSF-cNs in ectopic position. Employing in silico analyses, we ranked polymorphisms in C57Bl/6N substrain and selected genes Crb1, Cyfip2, Adamts12, Plk1, and Herpud2 as the most probable candidates, whose product dysfunction might be responsible for the ectopic distribution of CSF-cNs. Furthermore, segregation analysis of F2 progeny of parental C57Bl/6N and Balb/C mice revealed that polymorphic loci of Crb1 and Cyfip2 underlie the ectopic position of CSF-cNs in the spinal cord of C57Bl/6N mice.

Oncogenic BRAF and KRAS mutations in endosalpingiosis.

Endosalpingiosis, a microscopic lesion composed of ectopic Fallopian tube epithelium, frequently involves the peritoneum and lymph nodes in patients with ovarian serous borderline tumour or low-grade serous carcinoma, but its pathogenic significance remains unclear. Using laser-capture microdissection and droplet digital PCR, we investigated whether endosalpingiosis harbours the driver mutations in BRAF and KRAS that characterise ovarian low-grade serous neoplasms. Somatic mutations were detected in 14 (33%) of 43 endosalpingiotic lesions analysed. Of 21 women with endosalpingiosis associated with a synchronous or metachronous ovarian low-grade serous tumour, mutations were identified in endosalpingiotic lesions from 11 (52%) women, with most cases (10/11, 91%) demonstrating identical mutations in both tumour and endosalpingiosis. In contrast, of 13 cases of endosalpingiosis not associated with an ovarian tumour, only one harboured a KRAS mutation. The proliferative activity as assessed by Ki-67 immunohistochemistry was lower in endosalpingiosis than in low-grade serous tumours, and endosalpingiosis with either a BRAF or KRAS mutation had a significantly lower Ki-67 index than those without. Ectopic expression of KRASG12V in Fallopian tube epithelial cells led to ERK phosphorylation, p21 induction, growth arrest and cellular senescence. In conclusion, we demonstrate that endosalpingiosis represents an interesting example of cancer driver mutations in deceptively normal-appearing cells, which may be prone to neoplastic transformation upon bypass of endogenous oncosuppressive mechanisms. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Ectopic Posterior Pituitary, Polydactyly, Midfacial Hypoplasia and Multiple Pituitary Hormone Deficiency due to a Novel Heterozygous IVS11-2A>C(c.1957-2A>C) Mutation in the GLI2 Gene

A novel heterozygous IVS11-2A>C(c.1957-2A>C) mutation in the GLI2 gene is reported. There was an extremely distinct phenotypical expression in two siblings and their father. The index case was a boy who developed cholestasis and hypoglycaemia in the neonatal period. He had bilateral postaxial polydactyly, mid-facial hypoplasia, high palatal arch, micropenis, and bilateral cryptorchidism. Laboratory examination revealed a diagnosis of multiple pituitary hormone deficiency. There was severe anterior pituitary hypoplasia, absent pituitary stalk and ectopic posterior pituitary on magnetic resonance imaging which suggested pituitary stalk interruption syndrome with no other midline structural abnormality. Molecular genetic analysis revealed a novel heterozygous splicing IVS11-2A>C(c.1957-2A>C) mutation detected in the GLI2 gene. His father and a six-year-old brother with the identical mutation also had unilateral postaxial polydactyly and mid-facial hypoplasia although there was no pituitary hormone deficiency. This novel heterozygous GLI2 mutation detected appears to present with an extremely variable clinical phenotype, even in related individuals with an identical mutation, suggesting incomplete penetrance of this GLI2 mutation.

MicroRNA-142-3p suppresses endometriosis by regulating KLF9-mediated autophagy in vitro and in vivo.

The detailed pathogenesis of endometriosis remains largely unclear despite decades of research. Recent studies have demonstrated that miRNAs plays an important role in endometriosis. The expression of miR-142-3p was decreased in ectopic endometrial tissues, while KLF9 and VEGFA expression levels were increased. Overexpression of miR-142-3p or knockdown of KLF9 significantly suppressed CRL-7566 cell proliferation and metastasis, induced cell apoptosis, and decreased both cell autophagy and vascularization. Additionally, KLF9 was confirmed to be a direct target of miR-142-3p and to directly bind to the promoter of the VEGFA gene, regulating its expression. Finally, intraperitoneal injection of miR-142-3p lentivirus significantly attenuated ectopic endometriotic lesions in vivo.miR-142-3p directly targeted KLF9, regulated VEGFA expression, and was protective against the growth of ectopic endometriotic lesions. Therefore, the miR-142-3p/KLF9/VEGFA signalling pathway may be a potential target in endometriosis treatment.

MicroRNA-126-5p downregulates BCAR3 expression to promote cell migration and invasion in endometriosis.

PURPOSE: Endometriosis (EMs) is an estrogen-dependent multifactorial disease. Inhibition of estrogen in endometrial cells contributes to their failure to form lesions in ectopic sites. However, whether reducing or suppressing the inhibitory effect of estrogen results in the establishment of ectopic lesions remains unclear. The BCAR3 gene induces estrogen resistance in estrogen-dependent breast cancer cells and promotes cell migration, invasion, and epithelial-mesenchymal transition (EMT). However, the expression of BCAR3 in endometriosis and its effect on endometrial cell function and the anti-estrogen effect of endometriosis have not been reported. These issues are addressed in the present study. METHODS: The study included 32 cases of ectopic endometrium and eutopic endometrium in patients with endometriosis and 31 cases of normal endometrium as controls. The expression of BCAR3 and microRNA (miR)-126-5p was detected by real-time PCR, immunohistochemistry, and western blotting. The effects of BCAR3 and miR-126-5p on the morphology and biological behavior of eutopic endometrial cells were verified using lentivirus overexpression and a vector knockdown model, the CCK-8 assay, Transwell experiments, and estrogen intervention experiments using primary cultures of epithelial and stromal cells. RESULTS: The BCAR3 gene was highly expressed in ectopic endometrium and the eutopic endometrium of patients with endometriosis, and the expression level was higher in stage III-IV patients than in stage I-II patients. In vitro cell experiments showed that miR-126-5p negatively regulated the expression of BCAR3 and its effect on the migration and invasion of stromal cells. Low expression of miR-126-5p and high expression of BCAR3 promoted endometriosis stromal cell migration and invasion. Assessment of EMT in endometriosis compared with eutopic endometrium showed that the expression of vimentin was significantly increased and the expression of E-cadherin was significantly decreased in ectopic endometrium. Estrogen promoted EMT in eutopic endometrial epithelial cells and this effect was reversed by estrogen inhibitors. BCAR3 had no direct effect on EMT and did not act synergistically with estrogen on promoting EMT. CONCLUSION: miR-126-5p negatively regulated BCAR3 expression in eutopic endometriosis, enhanced the migration and invasion of endometrial cells, and promoted the occurrence of endometriosis. BCAR3 did not induce EMT and had no synergistic effect with estrogen, but its inhibition of anti-estrogen function may provide new insight into the mechanism of local estrogen action in endometriosis.

Lack of CD45 in FLT3-ITD mice results in a myeloproliferative phenotype, cortical porosity, and ectopic bone formation.

The receptor tyrosine kinase FLT3 is expressed in myeloid and lymphoid progenitor cells. Activating mutations in FLT3 occur in 25-30% of acute myeloid leukaemia (AML) patients. Most common are internal tandem duplications of sequence (ITD) leading to constitutive FLT3-ITD kinase activity with an altered signalling quality promoting leukaemic cell transformation. Here, we observed the attenuating role of the receptor-like protein tyrosine phosphatase (RPTP) CD45/Ptprc in FLT3 signalling in vivo. Low level expression of this abundant RPTP correlates with a poor prognosis of FLT3-ITD-positive AML patients. To get a further insight into the regulatory role of Ptprc in FLT3-ITD activity in vivo, Ptprc knock-out mice were bred with FLT3-ITD knock-in mice. Inactivation of the Ptprc gene in FLT3-ITD mice resulted in a drastically shortened life span and development of severe monocytosis, a block in B-cell development and anaemia. The myeloproliferative phenotype was associated with extramedullary haematopoiesis, splenohepatomegaly and severe alterations of organ structures. The phenotypic alterations were associated with increased transforming signalling of FLT3-ITD, including activation of its downstream target STAT5. These data reveal the capacity of Ptprc for the regulation of FLT3-ITD signalling activity in vivo. In addition, histopathology and computed tomography (CT) revealed an unexpected bone phenotype; the FLT3-ITD Ptprc-/- mice, but none of the controls, showed pronounced alterations in bone morphology and, in part, apparent features of osteoporosis. In the spleen, ectopic bone formation was observed. The observed bone phenotypes suggest a previously unappreciated capacity of FLT3-ITD (and presumably FLT3) to regulate bone development/remodelling, which is under negative control of CD45/Ptprc.

Pax2 is essential for proliferation and osteogenic differentiation of mouse mesenchymal stem cells via Runx2.

Mesenchymal stem cells (MSCs) have been widely studied in the field of regenerative medicine with the potential to solve osteoporosis. Paired box 2 (Pax2), as a transcription factor, is the master regulator of embryogenesis and oncogenesis. However, the function of Pax2 in osteogenesis is unknown. Here, we reported for the first time that the expression of Pax2 gradually increased during osteogenic differentiation of mouse MSCs, and osteoprogenitor cells. However, detected in osteoblastic cells of mouse tibia, the expression of Pax2 in the embryonic stage was higher than that in adulthood. In C3H/10/T1/2 cells and compact bone-derived mouse MSCs (mMSCs), Pax2 knock-down inhibited the proliferation of these cells, down-regulated the expression of osteogenic marker genes, as well as repressed the ALP activity and mineralization. In addition, Pax2 enhanced the transcriptional activity of Runx2, and activated the MAPK pathway genes (ERK, JNK and p38). Furthermore, knock-down of Pax2 repressed the mMSCs-mediated bone regeneration in an ectopic bone formation model. In conclusion, Pax2 promotes osteogenesis of mouse MSCs, suggesting that Pax2 has a role in the pathophysiology of bone related diseases, and has potential application in bone tissue regeneration.

Neurog3-dependent pancreas dysgenesis causes ectopic pancreas in Hes1 mutant mice.

Mutations in Hes1, a target gene of the Notch signalling pathway, lead to ectopic pancreas by a poorly described mechanism. Here, we use genetic inactivation of Hes1 combined with lineage tracing and live imaging to reveal an endodermal requirement for Hes1, and show that ectopic pancreas tissue is derived from the dorsal pancreas primordium. RNA-seq analysis of sorted E10.5 Hes1+/+ and Hes1-/- Pdx1-GFP+ cells suggested that upregulation of endocrine lineage genes in Hes1-/- embryos was the major defect and, accordingly, early pancreas morphogenesis was normalized, and the ectopic pancreas phenotype suppressed, in Hes1-/-Neurog3-/- embryos. In Mib1 mutants, we found a near total depletion of dorsal progenitors, which was replaced by an anterior Gcg+ extension. Together, our results demonstrate that aberrant morphogenesis is the cause of ectopic pancreas and that a part of the endocrine differentiation program is mechanistically involved in the dysgenesis. Our results suggest that the ratio of endocrine lineage to progenitor cells is important for morphogenesis and that a strong endocrinogenic phenotype without complete progenitor depletion, as seen in Hes1 mutants, provokes an extreme dysgenesis that causes ectopic pancreas.

Nobiletin alleviates endometriosis via down-regulating NF-κB activity in endometriosis mouse model.

Nobiletin exhibits protective potential on inflammation and inhibits the activation of transcription factors nuclear factor-κB (NF-κB). However, its effects on the progression of endometriosis remain unsettled. The present study aimed to explore the in vivo alleviation of nobiletin on endometriosis and its mechanism of action. The mouse model of endometriosis was established and administered with nobiletin. The ectopic lesion size was measured and the hotplate test was performed to assess the amelioration of nobiletin on endometriosis. The expression of proliferation and angiogenesis relevant genes including proliferating cell nuclear antigen (PCNA), vascular endothelial growth factor (VEGF), and E-cadherin was measured by immunostaining and the mRNA expression of proinflammatory mediators including interleukin (IL)-6, IL-1ß, tumor necrosis factor (TNF)-α, matrix metalloproteinases (MMP)-1, and MMP-3 was measured by RT-PCR. The change of NF-κB activity in endometriotic cells was evaluated by Western blotting and confirmed by luciferase assay. Administration of nobiletin significantly reduced lesions size and pain in endometriosis mice. Nobiletin significantly altered the expression of PCNA, VEGF, and E-cadherin in ectopic endometrium, as well as the levels of IL-6, IL-1ß, TNF-α, MMP-1, and MMP-3. Nobiletin also showed remarkably impairment on the activation of NF-κB in promoting endometriotic cells, likely targeting on the activity of IκB kinases (IKKs). The present study provides the first evidence that nobiletin exerts protection on endometriosis via inhibition the activation of NF-κB, specifically on the activity of IκB kinases.