Expression Of Sox2 Research Articles

SLC13A5 plays an essential role in the energy shift to oxidative phosphorylation in cisplatin-resistant mesothelioma stem cells.

Mesothelioma is a highly aggressive tumor affecting an increasing number of patients worldwide. Owing to the poor clinical outcomes associated with current therapies, the development of novel therapies that target cancer stem cells (CSCs) is desirable. Here, we examined the applicability of our previously established hydrogel-based rapid CSC generation method to human mesothelioma cell lines and further analyzed the characteristics of the induced mesothelioma stem cell (MesoSC) -like cells. Human mesothelioma cell lines cultured on hydrogels presented increased expression of pan-stem cell markers and acquired spheroid formation and early tumorigenicity, suggesting that MesoSC-like cells are highly malignant. Microarray analysis demonstrated that the expression of SLC13A5, a citrate transporter involved in TCA cycle, was significantly induced in the resulting MesoSC-like cells. The overexpression of SLC13A5 resulted in a metabolic shift toward oxidative phosphorylation, increased phosphorylation of ERK and YAP, and increased SOX2 expression, leading to increased cisplatin resistance. scRNA-seq database analysis revealed that clinical mesothelioma samples contained a small number of SLC13A5-expressing cells. Our findings suggest that the hydrogel-based CSC generation method is also effective for human mesothelioma cells and that SLC13A5 may contribute to MesoSC survival. The new properties of MesoSCs revealed in this study may provide clues for establishing future treatments.

An inducible mouse model of OI type V reveals aberrant osteogenesis caused by Ifitm5 c.-14C > T mutation.

Osteogenesis imperfecta (OI) Type V is typically characterized by radial head dislocation, calcification of interosseous membrane and hyperplastic callus. It is caused by the c.-14C > T mutation in the 5' UTR of IFITM5 gene, adding five amino acids (MALEP) to the N-terminal of IFITM5 protein. Previous studies have suggested a neomorphic function of the MALEP-IFITM5 protein. However, the underlying mechanisms remain unclear due to embryonic lethality in previous mouse models. Therefore, we developed an inducible mouse model (Ifitm5flox c.-14C > T) that could be induced by Cre expressed at different developmental stages to explore the pathogenic effects of the neomorphic MALEP-IFITM5. The mutant Ifitm5 allele could be regulated by the endogenous regulatory elements after Cre recombination, maintaining its spatiotemporal expression pattern and physiological level. Specifically, Prx1-Cre; Ifitm5flox c.-14C > T mutant mice were born with fractures in all limbs, showing impaired ossification and enhanced chondrogenesis associated with increased SOX9 abundance. Analyses of single-cell RNA sequencing data revealed arrested osteogenesis in Prx1-Cre; Ifitm5flox c.-14C > T mouse. A major population of cells expressing both osteogenic and chondrogenic signature genes was identified in the mutant mouse. Reduced expression of SP7 and SOST in the cortical regions of mutant mice confirmed delayed osteocyte maturation and compromised osteogenesis. Elevated bone marrow adipocytes were found in the adult mutant mice. Ectopic chondrogenesis and SOX9 expression were also observed in the perichondrium regions of Col1a1-Cre; Ifitm5flox c.-14C > T and Ocn-Cre; Ifitm5flox c.-14C > T mutant mice. The inducible Ifitm5flox c.-14C > T mouse model and integrated single-cell transcriptomic analyses elucidated that ectopic expression of SOX9 and disrupted homeostatic balance among osteogenesis, chondrogenesis and adipogenesis may contribute to the pathogenesis caused by MALEP-IFITM5, helping to gain deeper insights into the molecular mechanisms of type V OI.

Targeting UBE2T suppresses breast cancer stemness through CBX6-mediated transcriptional repression of SOX2 and NANOG.

Breast cancer stem cells (BCSCs) are the main cause of breast cancer recurrence and metastasis. While the ubiquitin-proteasome system contributes to the regulation of BCSC stemness, the underlying mechanisms remain unclear. Here, we identified ubiquitin-conjugating enzyme E2T (UBE2T) as a pivotal ubiquitin enzyme regulating BCSC stemness through systemic screening assays, including single-cell RNA sequencing (scRNA-seq) and stemness-index analysis. We found that patients with high UBE2T expression exhibited worse prognosis than those with low expression (10-year PFS: 55.95% vs. 85.08%), which are consistent across various subtypes of breast cancers. Genetic ablation of UBE2T suppresses BCSC stemness and tumor progression in organoids and spontaneous MMTV-PyMT mice, dependent on the transcriptional inactivation of pluripotency genes SOX2 and NANOG. Mechanically, UBE2T collaborates with the E3 ligase TRIM25 to perform K48-linked polyubiquitination and degradation of CBX6 at K214, which deficiency helps to promote the transcription of SOX2 and NANOG and enhances BCSC stemness. The pharmacological inhibitor of UBE2T significantly reduced the expression of NANOG and SOX2, suppressed tumor progression, and demonstrated synergistic effects when combined with chemotherapeutics, but not with other treatments. Collectively, our study revealed that the UBE2T-TRIM25-CBX6 axis can regulate BCSC stemness and offers a potentially therapeutic strategy to combat breast cancer in a clinical translation setting.

MFAP5 Strengthened the Stem Cell Features of Non-small Cell Lung Cancer Cells by Regulating the FBW/Sox9 Axis.

Non-small cell lung cancer (NSCLC) is a type of malignant tumor with high morbidity as well as mortality. The process of lung cancer may be driven by cancer stem cells. It was known that MFAP5 enhanced the occurrence of diverse types of cancer. Also, MFAP5 has the potential to induce the degradation of FBW7 which is a tumor suppressor. Lower levels of FBW7 enhance the stability of Sox9, which is the cancer stem cell-related protein. However, whether the MFAP5 can modulate the stem cell features of NSCLC cells by modulating the FBW7/Sox9 axis is unclear. Therefore, this study aimed to explore the role of MFAP5/FBW7/Sox9 axis on the stem cell features of NSCLC cells and develop a new treatment of this carcinoma. In this study, we explored the effects of MFAP5 on the stem cell features of NSCLC cells for the first time. We established MFAP5 overexpression and knockdown NSCLC cells. Clone formation assays and cell sphere culture assays were conducted for the exploration of the growth and stem cell features of these cells. Western blotting was applied for the detection of Sox9 and FBW7 expression in these cells. CHX was applied for the treatment of these cells for the detection of degradation of Sox9. Finally, we overexpressed the Sox9 in MFAP5 knockdown NSCLC cells. MFAP5 promoted the growth and stem cell features of these cells. Knockdown of MFAP5 induced higher levels of FBW7 while restricting the expression of Sox9. Knockdown of MFAP5 aggravated the degradation of Sox9. Overexpression of Sox9 abrogated the efficacy of MFAP5 inhibition on the growth as well as stem cell features of these cells. The results of this study clarified the role of MFAP5/FBW7/Sox9 axis on the development of non-small cell lung cancer cells, providing the potential therapeutic target for the clinical treatment of NSCLC. MFAP5 maintained the stem cell features of non-small cell lung cancer cells by modulating FBW7/Sox9 axis.

PRRX1-Rearranged Mesenchymal Tumor in a Core Needle Biopsy.

PRRX1-rearranged mesenchymal tumors are a recently described subset of soft tissue tumors, characterised by a PRRX1::NCOA1/2 or PRRX1::KMT2D gene fusion and by distinctive morphological features.1 They show a circumscribed, multi-nodular growth pattern with bland spindle cells in a myxo-collagenous stroma, surrounded by staghorn-like vessels with perivascular hyalinization. First described by Lacambra et al in 2019,2 they were originally named PRRX1-NCOAx-rearranged fibroblastic tumors. A total of 22 tumors have been reported since then.1- 7 Later, a subsequent study expanded the molecular spectrum of these tumors by detecting an alternative PRRX1::KMT2D fusion and variable degrees of S100 and SOX10 expression in a subset of tumors, which led to a proposed revision of the original nomenclature to PRRX1-rearranged mesenchymal tumors, a term, that comprises also tumors with non-NOCA1/2 fusion partners and allows for the possibility of partial neural or neuroectodermal differentiation. Loss of RB1 has been recently detected in two PRRX1-rearranged mesenchymal tumors on immunohistochemistry and FISH analysis,7 suggesting a potential overlap with RB1-deficient soft tissue tumors. As an emerging entity, PRRX1-rearranged mesenchymal tumors have not been included (yet) in the publication of the 2020 World Health Organization classification of soft tissue and bone tumors.8.

Enhanced Chondrogenic Potential and Osteoarthritis Treatment Using Cyaonoside A-Induced MSC Delivered via a Hyaluronic Acid-Based Hydrogel System.

Osteoarthritis (OA) is a prevalent degenerative joint disease that significantly impacts the quality of life in the elderly. Traditional Chinese medicine, particularly Medicinal Cyathula Root and its active component Cyaonoside A (CyA), has been utilized to treat OA by promoting chondrocyte proliferation, inhibiting inflammatory factors, and maintaining joint homeostasis. Concurrently, mesenchymal stem cells (MSC) derived from placental umbilical cord, bone marrow, and adipose tissue have gained attention for their potential in OA treatment due to their chondrogenic differentiation capabilities. This study explored the therapeutic synergy of CyA and MSC for enhanced cartilage regeneration. Optimal chondrogenic differentiation was achieved by treating MSC with 0.5 mg/mL CyA for 3 days, significantly increasing the expression of key cartilage-specific genes ACAN, COL2A, and SOX9. Comparative gene expression and pathway analyses revealed that CyA-induced MSC (C-MSC) modulate critical signaling pathways, including TGF-β, PI3K-Akt, and Wnt, demonstrating their potential in cartilage repair. Furthermore, C-MSC-derived exosomes exhibited superior anti-inflammatory and anti-apoptotic effects compared to MSC-derived exosomes in IL-1β-treated human chondrocytes, enhancing chondrogenic gene expression and reducing cartilage degradation. To enable targeted delivery, a novel injectable hydrogel system (HAMA@C-MSC) was developed using methylacrylated hyaluronic acid (HAMA). This hydrogel facilitated uniform cell distribution, maintained structural integrity, and demonstrated excellent biocompatibility and biosafety, with no cytotoxic or hemolytic effects. In vivo studies using a rat destabilization of the medial meniscus OA model confirmed that HAMA@C-MSC significantly improved cartilage structure, enhanced chondrocyte regeneration, and restored collagen integrity, outperforming other treatment groups as validated through imaging, histology, and molecular analyses. These findings highlight HAMA@C-MSC as a promising therapeutic strategy for OA, leveraging the synergistic effects of C-MSC and advanced hydrogel technology to achieve enhanced cartilage regeneration and joint protection.

Role of Kctd13 in modulating AR and SOX9 expression in different penile cell populations.

Micropenis is a condition with significant physical and psychological implications caused mainly by decreased androgen action in penile development. Kctd13-knockout (Kctd13-KO) mice have micropenis, cryptorchidism, and fertility defects because of reduced levels of androgen receptor (AR) and SOX9. We hypothesized that normalizing the levels of AR and SOX9 in the Kctd13-KO penis could help us to understand the mechanism of action of these signaling pathways on penile development. We generated transgenic mice lacking Kctd13 and conditionally expressing AR in the urethral mesenchyme after Cre activation with Twist2cre (Kctd13-KO; AR-CMV; Twist2cre; herein called AR+), and Sox9 in the urethral epithelium after Cre activation with Shhcre (Kctd13-KO; Sox9-CAG; Shhcre; herein called SOX9+). Mice penile morphology, fertility, and the effect of KCTD13 on AR and SOX9 ubiquitination were evaluated. Kctd13-KO micropenis phenotype was rescued after increasing levels of penile AR or SOX9 as transgenic AR+ and SOX9+ mice have longer penile lengths than Kctd13-KO mice and are comparable to WT mice. In addition, male-urogenital-mating-protuberance and the baculum were significantly shorter and narrower in Kctd13-KO mice compared with transgenic AR+ and SOX9+ mice. The position of the urethral meatus was similar and orthotopic in location in Kctd13-KO, AR+, SOX9+, and WT penises indicating that none of these mice had hypospadias. The subfertility of AR+ and SOX9+ mice was improved. The ectopic expression of KCTD13 in HEK293 cells strongly reduced AR ubiquitination which is abolished when the proteasome pathway is inhibited and this process is mediated by the ubiquitin ligase, STUB1. The effect of KCTD13 on SOX9 ubiquitination is minimal. KCTD13 regulates AR ubiquitination by modulating STUB1 binding to AR. Penile restoration of AR and SOX9 improved penile development in Kctd13-KO mice allowing us to discern the contribution from individual signaling pathways and cell types in penile development.

Mesenchymal Stem Cell-conditioned Medium Attenuated CoCl2-induced Injury of Renal Tubular Epithelial Cells by Inhibiting NCOA1, HIF-1α, and Sox9.

Renal interstitial fibrosis (RIF) constitutes the ultimate pathological alteration in nearly all chronic kidney diseases (CKD). Mesenchymal stem cell conditioned medium (MSC-CM) exhibits an alleviating impact on renal fibrosis; however, the underlying mechanism remains unclear. The objective of this study was to explore whether MSC-CM regulates the expression of α-smooth muscle actin (α-SMA), Transforming growth factor-β1 (TGF-β1), Hypoxia-inducible factor-1α (HIF-1α), Nuclear receptor coactivators (NCOA1), and SRY-related high mobility (Sox9). Rat renal tubular epithelial cells (RTECs), NRK-52E, were treated with diverse concentrations of Cobalt chloride (CoCl2) for 24 hours. The survival rate and protein expression of NRK-52E cells exposed to different concentrations of CoCl2 were determined to identify the final concentration. Three groups of NRK-52E cells were employed in the experiment: the normal control group, the 400 μM CoCl2 group, and the MSC-CM + 400 μM CoCl2 group. The cell morphology was observed by an inverted phase contrast microscope and scanning electron microscope, and the protein expressions of α-SMA, TGF-β1, HIF-1α, NCOA1, and Sox9 were detected. The microscopic findings demonstrated that MSC-CM was able to decrease the degree of cytochemical hypoxia damage in NRK-52E cells induced by CoCl2. Immunofluorescence and Western blot analyses also affirmed a similar tendency. The upregulation of α-SMA, TGF-β1, HIF-1α, NCOA1, and Sox9 triggered by CoCl2 could be inhibited following MSC-CM intervention. Our findings indicate that MSC-CM exerts a protective effect on RTECs by down-regulating α-SMA, TGF-β1, HIF-1α, NCOA1, and Sox9.

Variants in the SOX9 transactivation middle domain induce axial skeleton dysplasia and scoliosis

SOX9 is a crucial transcriptional regulator of cartilage development and homeostasis. Dysregulation of SOX9 is associated with a wide spectrum of skeletal disorders, including campomelic dysplasia, acampomelic campomelic dysplasia, and scoliosis. Yet how SOX9 variants contribute to the spectrum of axial skeletal disorders is not well understood. Here, we report four pathogenic variants of SOX9 identified in a cohort of patients with congenital vertebral malformations. We report a pathogenic missense variant in the transactivation middle (TAM) domain of SOX9 associated with mild skeletal dysplasia and scoliosis. We isolated a Sox9 mutant mouse with an in-frame microdeletion in the TAM domain (Sox9Asp272del), which exhibits skeletal dysplasia including kinked tails, rib cage anomalies, and scoliosis in homozygous mutants. We find that both the human missense and the mouse microdeletion mutations resulted in reduced SOX9 protein stability in cell culture, while Sox9Asp272del mutant mice show decreased SOX9 expression in the growth plate and annulus fibrosus tissues of the spine. This reduction in SOX9 expression was correlated with the reduction of extracellular matrix components, such as tenascin-X and the Adhesion G-protein coupled receptor ADGRG6. In summary, our work identified and modeled a pathologic variant of SOX9 within the TAM domain and demonstrated its importance for SOX9 protein stability. Our work demonstrates that SOX9 stability is important for the regulation of ADGRG6 expression, which is a known regulator of postnatal spine homeostasis, underscoring the essential role of SOX9 dosage in a spectrum of axial skeleton dysplasia in humans.

CircPIK3C3 inhibits hepatocellular carcinoma progression and lenvatinib resistance by suppressing the Wnt/β-catenin pathway via the miR-452-5p/SOX15 axis.

Resistance to lenvatinib limits the effectiveness of the targeted treatments for HCC. However, the exact mechanism behind this resistance remains elusive. Current research suggests that circular RNA (circRNA) is pivotal in mediating drug resistance during targeted treatments. To investigate the influence of circRNA on HCC progression and its resistance to lenvatinib. We identified the crucial circRNA hsa_circ_0005711 (circPIK3C3) through bioinformatics. Study (in-vitro and in-vivo) on the expression of circPIK3C3 (measured by qRT-PCR) and its association with progress of HCC patients including lenvatinib resistance were performed. Techniques such as dual-luciferase reporter assays, RNA FISH, RAP, and AGO2-RIP were employed for discerning circPIK3C3's specific mechanisms related to progression of HCC and its lenvatinib resistance. Study (in-vitro and in-vivo) revealed that circPIK3C3 exhibited reduced expression and lenvatinib resistance in HCC, which was intimately tied to patient outcomes. Moreover, circPIK3C3 elevated SOX15 expression while suppressing the signaling pathway related to Wnt/β-catenin via inhibition of miR-452-5p through a competitive endogenous RNA (ceRNA) network. This, in turn, mitigated HCC progression and its resistance to lenvatinib. CircPIK3C3 is instrumental in the disease progression and resistance to Lenvatinib in HCC. It presents a potential therapeutic avenue for patients with lenvatinib-resistant HCC and could serve as a valuable molecular marker for forecasting lenvatinib resistance in HCC patients.

Epithelial-Mesenchymal Transition Functions as a Driver for the Direct Conversion of Somatic Cells.

Direct conversion is an innovative new technology that involves the conversion of somatic cells to target cells without passing through a pluripotent state. Forced expression alone or in combination with transcription factors (TFs), which are critical for the generation of target cells, is important for successful direct conversion. However, most somatic cells are unable to directly convert into target cells even with forced expression. We herein demonstrated that epithelial-mesenchymal transition (EMT) is advantageous for the direct conversion of somatic cells. We previously reported that mouse keratinocytes converted into neural crest cells (NCCs) following the forced expression of the NCC specifier Sox10 in combination with expression of the TFs Snail1, Slug, Twist1, and Tcfap2a (4 TFs). 4 TFs induced EMT in keratinocytes; therefore, EMT was considered to be advantageous for direct conversion. The direct conversion of mouse mammary gland epithelial cells (NMuMG cells) into NCCs was not observed with the forced expression of Sox10, but was detected with the expression of Sox10 following the induction of EMT by 4 TFs. Furthermore, TGF-β1-induced EMT and Sox10 expression directly converted NMuMG cells into NCCs. These results suggest that the induction of EMT in somatic cells is advantageous for direct conversion.

MTORC1 regulates the proliferation of SOX9+ porcine skin-derived stem cells (pSDSCs) by promoting S6K phosphorylation.

Skin-derived stem cells (SDSCs) are a subtype of adult stem cells (ASCs) that are widely harvested and exempt from ethical restrictions in clinical applications. These cells possess capabilities for self-renewal, proliferation, and multi-lineage differentiation. Compared to model animals like rats and mice, pigs exhibit greater physiological similarity to humans. Porcine skin has very similar histological and physiological characteristics to human skin. Therefore, porcine skin is becoming increasingly significant as an in vitro model for research. In this study, porcine skin-derived stem cells (pSDSCs) were isolated and cultured in vitro for experiments. The expression of stemness-related gene SOX9 was detected. RNA sequencing (RNA-seq) results found that the mammalian target of rapamycin (mTOR) signaling pathway was significantly enriched in SOX9+ pSDSCs. To investigate the role of the mTOR signaling pathway, we added rapamycin (RAPA), an inhibitor of the mTORcomplex1 (mTORC1), and found that the proliferation rate of SOX9+ pSDSCs decreased significantly during culture. In addition, western blotting (WB) results demonstrated that mTORC1 promoted proliferation by phosphorylating S6 kinase (S6K) and then activating cyclin D1(CCND1) in SOX9+ pSDSCs. These findings provide insights into the mechanisms of adult stem cell proliferation.

Positive autoregulation of Sox17 is necessary for gallbladder and extrahepatic bile duct formation.

Expression of SRY-box transcription factor 17 (Sox17) in the endodermal region caudal to the hepatic diverticulum during late gastrulation is necessary for hepato-pancreato-biliary system formation. Analysis of an allelic series of promoter-proximal mutations near the transcription start site (TSS) 2 of Sox17 in mouse has revealed that gallbladder (GB) and extrahepatic bile duct (EHBD) development is exquisitely sensitive to Sox17 expression levels. Deletion of a SOX17-binding cis-regulatory element in the TSS2 promoter impairs GB and EHBD development by reducing outgrowth of the nascent biliary bud. These findings reveal the existence of a SOX17-dependent autoregulatory loop that drives Sox17 expression above a critical threshold concentration necessary for GB and EHBD development to occur, and that minor impairments in Sox17 gene expression are sufficient to impair the expression of SOX17-regulated genes in the nascent GB and EHBD system, impairing or preventing development.

Combination of rapamycin and adipose-derived mesenchymal stromal cells enhances therapeutic potential for osteoarthritis

BackgroundThe regenerative potential of mesenchymal stromal/stem cells (MSCs) has been extensively studied in clinical trials in the past decade. However, despite the promising regenerative properties documented in preclinical studies, for instance in osteoarthritis (OA), the therapeutic translation of these results in patients has not been fully conclusive. One factor contributing to this therapeutic barrier could be the presence of senescent cells in OA joints.MethodsThis study evaluated a novel approach to OA treatment by combining adipose tissue-derived MSCs (AD-MSCs) with rapamycin, a clinically approved immunosuppressive drug with anti-senescence properties. First, rapamycin effects on senescence and fibrosis markers were investigated in freshly isolated OA chondrocytes by immunostaining. Next, the in vitro differentiation capacities of AD-MSCs, their regulatory immune functions on activated immune cells and their regenerative effects on OA chondrocyte signature were assessed in the presence of rapamycin.ResultsIn OA chondrocytes, rapamycin reduced the senescence marker p15INK4B and the fibrosis marker COL1A1 without affecting the expression of the master chondrogenic markers SOX9 and COL2. Rapamycin also enhanced AD-MSC differentiation into chondrocytes and reduced their differentiation into adipocytes. In addition, rapamycin improved AD-MSC immunoregulatory functions by promoting the expression of immunosuppressive factors, such as IDO1, PTGS2 and also CD274 (encoding PD-L1). Finally, RNA sequencing analysis showed that in the presence of rapamycin, AD-MSCs displayed improved chondroprotective regenerative effects on co-cultured OA chondrocytes.ConclusionsOur findings suggest that the rapamycin and AD-MSC combination enhances the therapeutic efficacy of these cells in senescence-driven degenerative diseases such as OA, notably by improving their anti-fibrotic and anti-inflammatory properties.Graphical abstract

Biomechanically inspired composite hydrogel bioink enhances engineered cartilage formation

Current therapies for articular cartilage defects or degeneration (osteoarthritis) remain unsatisfactory. There are significant clinical demands for the development of more efficient approaches to enhance the repair or regeneration of articular cartilage lesions. In this study, a newly defined alginate-gelatin (A-G) composite bioink was synthesized using the carbodiimide chemistry crosslinking method. Then, the dual-crosslinking (DC) bioscaffolds containing both chemical and ionic networks were fabricated by 3D-bioprinting technique and Ca2+ treatment. The optimized networks formed in the DC bioscaffolds provided a desirable Young’s modulus and geometric constraints, which were superior to that of the single-crosslinking (SC) control group to mimic the mechanical properties of the pericellular matrix (PCM) of native articular cartilage. Chondrocytes exhibited above 95% viability and higher proliferation rate in the 3D printed A-G-DC bioscaffolds than in the alginate-only group after 7 days in vitro culture. Chondrogenic differentiation in vitro was improved in the A-G-DC bioscaffolds than that of the alginate-only group, indexed by upregulation of chondrogenic marker gene expression including Sox9, Col2a1, Comp and Aggrecan. In the subcutaneous transplantation model and osteochondral defect model in mice with severe combined immunodeficiency (SCID), the A-G-DC bioscaffolds exhibited enhanced chondrogenesis and repair capacity than the alginate-only or none-implant control group, characterized by the increased expression of SOX9 and collagen type II (Col II) and higher ICRS II scores, respectively. These findings demonstrated that the biomechanically inspired A-G composite bioink and the 3D-printed A-G-DC bioscaffolds possess excellent cell biocompatibility, satisfactory biomechanical properties and chondrogenesis promotion capacity, which have the potential to be applied to enhance cartilage regeneration for patients with articular cartilage lesions.

Elevated SREBP1 accelerates the initiation and growth of pancreatic cancer by targeting SOX9

Pancreatic cancer is a lethal disease with an insidious onset, and little is known about its early molecular events. Here, we found that the sterol regulatory element-binding protein 1 (SREBP1) expression is gradually upregulated during the initiation of pancreatic cancer. Through in vitro 3D culture of pancreatic acinar cells and experiments in LSL-KrasG12D/+;Pdx1-Cre (KC) mice, we found that pharmacological inhibition of SREBP1 suppressed pancreatic tumorigenesis. In vitro, either knockdown or pharmacological inhibition of SREBP1 suppressed tumor proliferation but SREBP1 overexpression promoted tumor proliferation. In LSL-KrasG12D/+;Trp53fl/+;Pdx1-Cre (KPC) mice, we confirmed the tumor-promoting role of SREBP1 in pancreatic cancer progression. Mechanistically, we revealed SOX9 as a downstream target of SREPB1. SREBP1 inhibition decreased SOX9 expression in both acinar cells and pancreatic cancer cells. Indeed, we identified SREBP1 binding sites in the SOX9 promoter region and reported that SOX9 is transcriptionally regulated by SREBP1. Taken together, our findings demonstrate that SREBP1/SOX9 inhibition suppresses pancreatic cancer initiation and growth, suggesting that SREBP1 could serve as a potential target for cancer screening and treatment.

Modulation of Stemness and Differentiation Regulators by Valproic Acid in Medulloblastoma Neurospheres.

Changes in epigenetic processes such as histone acetylation are proposed as key events influencing cancer cell function and the initiation and progression of pediatric brain tumors. Valproic acid (VPA) is an antiepileptic drug that acts partially by inhibiting histone deacetylases (HDACs) and could be repurposed as an epigenetic anticancer therapy. Here, we show that VPA reduced medulloblastoma (MB) cell viability and led to cell cycle arrest. These effects were accompanied by enhanced H3K9 histone acetylation (H3K9ac) and decreased expression of the MYC oncogene. VPA impaired the expansion of MB neurospheres enriched in stemness markers and reduced MYC while increasing TP53 expression in these neurospheres. In addition, VPA induced morphological changes consistent with neuronal differentiation and the increased expression of differentiation marker genes TUBB3 and ENO2 . The expression of stemness genes SOX2 , NES , and PRTG was differentially affected by VPA in MB cells with different TP53 status. VPA increased H3K9 occupancy of the promoter region of TP53 . Among the genes regulated by VPA, the stemness regulators MYC and NES showed an association with patient survival in specific MB subgroups. Our results indicate that VPA may exert antitumor effects in MB by influencing histone acetylation, which may result in the modulation of stemness, neuronal differentiation, and the expression of genes associated with patient prognosis in specific molecular subgroups. Importantly, the actions of VPA in MB cells and neurospheres include a reduction in the expression of MYC and an increase in TP53 .

Modulation of Stemness and Differentiation Regulators by Valproic Acid in Medulloblastoma Neurospheres.

Changes in epigenetic processes such as histone acetylation are proposed as key events influencing cancer cell function and the initiation and progression of pediatric brain tumors. Valproic acid (VPA) is an antiepileptic drug that acts partially by inhibiting histone deacetylases (HDACs) and could be repurposed as an epigenetic anticancer therapy. Here, we show that VPA reduced medulloblastoma (MB) cell viability and led to cell cycle arrest. These effects were accompanied by enhanced H3K9 histone acetylation (H3K9ac) and decreased expression of the MYC oncogene. VPA impaired the expansion of MB neurospheres enriched in stemness markers and reduced MYC while increasing TP53 expression in these neurospheres. In addition, VPA induced morphological changes consistent with neuronal differentiation and the increased expression of differentiation marker genes TUBB3 and ENO2. The expression of stemness genes SOX2, NES, and PRTG was differentially affected by VPA in MB cells with different TP53 status. VPA increased H3K9 occupancy of the promoter region of TP53. Among the genes regulated by VPA, the stemness regulators MYC and NES showed an association with patient survival in specific MB subgroups. Our results indicate that VPA may exert antitumor effects in MB by influencing histone acetylation, which may result in the modulation of stemness, neuronal differentiation, and the expression of genes associated with patient prognosis in specific molecular subgroups. Importantly, the actions of VPA in MB cells and neurospheres include a reduction in the expression of MYC and an increase in TP53.

Genomic and Transcriptomic Profiling of Digital Papillary Adenocarcinomas Reveals Alterations in MatrixRemodeling and Metabolic Genes.

Digital papillary adenocarcinoma (DPAC) is a rare but aggressive cutaneous malignant sweat gland neoplasm that occurs on acral sites. Despite its clinical significance, the cellular and genetic characteristics of DPAC remain incompletely understood. We conducted a comprehensive genomic and transcriptomic analysis of DPAC (n = 14) using targeted next-generation DNA and RNA sequencing, along with gene expression profiling employing the Nanostring Technologies nCounter IO 360 Panel. Gene expression in DPAC was compared to that in hidradenoma (n = 10). Immunohistochemistry was employed to validate gene expression. Two out of eight DPACs showed fusion gene rearrangements (CRTC3::MAML2 and TRPS1::PLAG1). No uniform mutational signature was detected in DPAC. Comparative gene expression analysis revealed an enrichment of genes related to matrix remodeling, metabolism, and DNA damage repair. Hallmark pathway analysis demonstrated significant upregulation of E2F target genes in DPAC compared to hidradenoma (p = 0.00710). Human papillomavirus-42 was found to be positive in all of our tested DPAC cases. Immunohistochemistry confirmed increased protein expression of CD56, CDC20, and SOX10 in DPAC. Notably, most DPAC tumors also exhibited B-cell infiltration, as indicated by CD20 staining. Our findings reveal novel fusions and validate altered replication pathways related to HPV42 in DPAC.

Vesicular glutamate release is necessary for neural tube formation.

The brain and spinal cord originate from a neural tube that is preceded by a flat structure known as the neural plate during early embryogenesis. In humans, failure of the neural plate to convert into a tube by the fourth week of pregnancy leads to neural tube defects (NTDs), birth defects with serious neurological consequences. The signaling mechanisms governing the process of neural tube morphogenesis are unclear. Here we show that in Xenopus laevis embryos, neural plate cells release glutamate during neural plate folding in a Ca 2+ and vesicular glutamate transporter-1 (VGluT1)-dependent manner. Vesicular release of glutamate elicits Ca 2+ transients in neural plate cells that correlate with activation of Erk1/2. Knocking down or out VGluT1 leads to NTDs through increased expression of Sox2, neural stem cell transcription factor, and neural plate cell proliferation. Exposure during early pregnancy to neuroactive drugs that disrupt these signaling mechanisms might increase the risk of NTDs in offspring.