pH-sensitive molybdenum (Mo)-based polyoxometalate nanoclusters have therapeutic efficacy in inflammatory bowel disease by counteracting ferroptosis.

Current therapeutic drugs for ulcerative colitis (UC) remained inadequate due to drug dependence and unacceptable adverse events. Reactive oxygen species (ROS) played a critical role in the occurrence and development of UC, which most likely benefited from treatment in scavenging ROS. In this study, we developed a pH-sensitive molybdenum-based polyoxometalate (POM) nanocluster, which might contribute to site specific colonic delivery and enhance systemic efficacy of UC treatment. Our results demonstrated that POM displayed robust ROS scavenging ability in vitro. POM could significantly alleviate the enteric symptoms and inflammatory indicators in DSS-induced UC mouse models. Flow cytometry showed an effective diminishment of macrophages, neutrophils and T cells infiltration after POM administration in UC models. Also, for the first time, we demonstrated that POM interfered with metabolic pathway associated to oxidative stress and partially improved the abnormal production of intestinal metabolites in UC to some extent. Benefiting from the ROS scavenging ability, POM attenuated ferroptosis in DSS induced UC, as evidenced by increase of GSH, down-expression of GPX4 and improvement in mitochondrial morphological changes. Meanwhile, there were no side effects on normal tissues. Thus, our powerful therapeutic effects pioneered the application of POM for safer and more effective POM-based UC therapy.

Endo-reduplication in mouse liver after conditional mutation of ORC2 and combined mutation of ORC1 and ORC2.

The six subunit Origin Recognition Complex (ORC) is essential for loading MCM2-7 at origins of DNA replication to promote initiation of DNA replication in organisms ranging from S. cerevisiae to humans. In rare instances, as in cancer cell-lines in culture with mutations in ORC1 , ORC2 or ORC5 , or in endo-reduplicating mouse hepatocytes in vivo without ORC1 , DNA replication has been observed in the virtual absence of individual ORC subunits. Although ORC1 is dispensable in the mouse liver for endo-reduplication, because of the homology of ORC1 with CDC6, it could be argued that CDC6 was substituting for ORC1 to restore functional ORC. Here, we have created mice with a conditional deletion of ORC2 , to demonstrate that mouse embryo fibroblasts require ORC2 for proliferation, but that the mouse hepatocytes can carry out DNA synthesis in vitro and endo-reduplicate in vivo , despite the deletion of ORC2 . Combining the conditional mutation of ORC1 and ORC2 revealed that the mouse liver can still carry out endo-reduplication despite the deletion of the two genes, both during normal development and after partial hepatectomy. Since endo-reduplication, like normal S phase replication, requires the presence of MCM2-7 on the chromatin, these results suggest that in primary hepatocytes there is a mechanism to load sufficient MCM2-7 to carry out effective DNA replication despite the virtual absence of two subunits of ORC.

c-Met-targeted near-infrared fluorescent probe for real-time depiction and dissection of perineural invasion and lymph node metastasis lesions in pancreatic ductal adenocarcinoma xenograft models.

Pancreatic ductal adenocarcinoma (PDAC), a fatal malignant tumour, has a high postoperative recurrence rate, mainly due to the difficulty of discerning occult lesions, including those related to perineural invasion (PNI) and lymph node metastasis (LNM). Cellular mesenchymal-epithelial transition factor (c-Met), an excellent imaging marker, is aberrantly expressed in the majority of PDACs. Thus, we plan to utilize a c-Met-targeted near-infrared fluorescent (NIRF) probe for real-time visualization and dissection of PDAC, and corresponding PNI and LNM lesions. Immunohistochemistry showed c-Met expression in PDAC, PNI and LNM reached 94.3% (100/106), 88.3% (53/60), and 71.4% (25/35), respectively, and its expression in PNI and LNM was significantly correlated with that in primary PDAC (r = 0.66, p < 0.0001 and r = 0.44, p < 0.01, respectively). SHRmAb-IR800 was successfully synthesized using an anti-c-Met antibody and a NIRF dye. The in vitro targeting ability of SHRmAb-IR800 was higher in CFPAC1 cells (c-Met positive) than in Miapaca-2 cells (c-Met negative) (p < 0.05). In vivo NIRF imaging of CFPAC1 subcutaneous tumours demonstrated higher accumulation of SHRmAb-IR800 than the control probe (p < 0.05). The signal-to-background ratio (TBR) of an orthotopic PDAC tumour was 3.38 ± 0.46, and imaging with SHRmAb-IR800 facilitated the resection of metastatic lesions with sensitivity and specificity values of 93.3% (56/60) and 87.1% (27/31), respectively. Furthermore, tiny PNI and LNM lesions in xenograft models were detected by NIRF imaging, with TBRs measuring 2.59 ± 0.19 and 2.88 ± 0.72, respectively. Therefore, the clinical translation of this probe might shed new light on NIRF-guided pancreatectomy and improve the surgical prognosis of PDAC patients.

Baf45a Mediated Chromatin Remodeling Promotes Transcriptional Activation for Osteogenesis and Odontogenesis.

Chromatin remodeling, specifically the tissue-specific regulation in mineralized tissues, is an understudied avenue of gene regulation. Here we show that Baf45a and Baf45d, two Baf45 homologs belong to ATPase-dependent SWI/SNF chromatin remodeling complex, preferentially expressed in osteoblasts and odontoblasts compared to Baf45b and Baf45c. Recently, biochemical studies revealed that BAF45A associates with Polybromo-associated BAF (PBAF) complex. However, the BAF45D subunit belongs to the polymorphic canonical BRG1-associated factor (cBAF) complex. Protein profiles of osteoblast and odontoblast differentiation uncovered a significant increase of BAF45A and PBAF subunits during early osteoblast and odontoblast maturation. Chromatin immunoprecipitation sequencing (ChIP-seq) during the bone marrow stromal cells (BMSCs) differentiation showed higher histone H3K9 and H3K27 acetylation modifications in the promoter of Baf45a and Baf45d and increased binding of bone and tooth specific transcription factor RUNX2. Overexpression of Baf45a in osteoblasts activates genes essential for the progression of osteoblast maturation and mineralization. Furthermore, shRNA-mediated knockdown of Baf45a in odontoblasts leads to markedly altered genes responsible for the proliferation, apoptosis, DNA repair, and modest decrease in dentinogenic marker gene expression. Assay for Transposase-Accessible Chromatin sequencing (ATAC-seq) assay in Baf45a knockout osteoblasts revealed a noticeable reduction in chromatin accessibility of osteoblast and odontoblast specific genes, along with transcription factor Atf4 and Klf4. Craniofacial mesenchyme-specific loss of Baf45a modestly reduced the mineralization of the tooth and mandibular bone. These findings indicated that BAF45A-dependent mineralized tissue-specific chromatin remodeling through PBAF-RUNX2 crosstalk results in transcriptional activation is critical for early differentiation and matrix maturation of mineralized tissues.

Fibroblast Activation Protein (FAP) Overexpression Induces Epithelial-Mesenchymal Transition (EMT) in Oral Squamous Cell Carcinoma by Down-Regulating Dipeptidyl Peptidase 9 (DPP9).

PURPOSE: Fibroblast activation protein (FAP) acts as a tumor promoter via epithelial-mesenchymal transition (EMT) in human oral squamous cell carcinoma (OSCC). The present study was designed to investigate the FAP targeting proteins and explore the precise mechanism by which FAP promotes EMT in OSCC. PATIENTS AND METHODS: Proteins interacting with FAP were found and filtered by immunoprecipitation-mass spectrometry (IP-MS). Both DPP9 protein and mRNA were examined in 90 paired OSCC samples and matched normal tissue. DPP9 knockdown was conducted to determine its function in OSCC in vitro and in vivo. RESULTS: Dipeptidyl peptidase 9 (DPP9) was identified as interacting with FAP intracellularly by IP-MS. The levels of both DPP9 protein and mRNA were down-regulated in OSCC tissue. Lower DPP9 expression was correlated with unfavorable survival rates of OSCC patients. DPP9 knockdown accelerates the proliferation of OSCC cells in vitro and in vivo. Overexpression of FAP leads to a reduction in DPP9 expression. Likewise, DPP9 overexpression reverses the proliferation, migration, invasion and EMT induced by FAP during OSCC. CONCLUSION: Our study finds that FAP promotes EMT of OSCC by down-regulating DPP9 in a non-enzymatic manner. FAP-DPP9 pathway could be a potential therapeutic target of OSCC.

M6A-related bioinformatics analysis reveals that HNRNPC facilitates progression of OSCC via EMT.

Increasing evidence suggests that N6-methyladenosine(m6A) has a vital role in cancer progression. Therefore, we aimed to explore the prognostic relevance of m6A-related genes in oral squamous cell carcinoma (OSCC). First, Expression profiles were downloaded from The Cancer Genome Atlas (TCGA) and m6A-related genes were extracted afterwards. Then, cluster analysis and principal component analysis (PCA) were used to analyze m6A-related genes. And differentially-expressed analysis was performed in R software. Furthermore, a risk model was constructed, and crucial m6A genes were selected to explore its biological effects in OSCC cells. Total of 13 m6A-related genes were extracted and 8 differentially-expressed genes were identified. Subsequently, m6A-based clustering showed 2 subtypes with different clinical outcome. In addition, a risk model was successfully established. Of 13 m6A-related genes, only heterogeneous nuclear ribonucleoprotein C (HNRNPC) might be an independent biomarker and mean unfavorable overall survival in OSCC by univariate and multivariate cox regression analysis. Functional studies revealed that overexpression of HNRNPC promoted carcinogenesis of OSCC via epithelial- mesenchymal transition (EMT). In total, a risk model of m6A-related genes in OSCC was established. Subsequently, HNRNPC was proved to promote OSCC carcinogenesis and be an independent biomarker prognostic biomarker of OSCC, suggesting that it might be a new biomarker and therapeutic target of OSCC.

MICROmanagement of Runx2 Function in Skeletal Cells.

PURPOSE OF REVIEW-: Precise and temporal expression of Runx2 and its regulatory transcriptional network is a key determinant for the intricate cellular and developmental processes in adult bone tissue formation. This review analyzes how microRNA functions to regulate this network, and how dysregulation results in bone disorders. RECENT FINDINGS-: Similar to other biologic processes, microRNA (miRNA/miR) regulation is undeniably indispensable to bone synthesis and maintenance. There exists a miRNA-RUNX2 network where RUNX2 regulates the transcription of miRs, or is post transcriptionally regulated by a class of miRs, forming a variety of miR-RUNX2 regulatory pathways which regulate osteogenesis. SUMMARY-: The current review provides insights to understand transcriptional-post transcriptional regulatory network governed by Runx2 and osteogenic miRs, and is based largely from in vitro and in vivo studies. When taken together, this article discusses a new regulatory layer of bone tissue specific gene expression by RUNX2 influenced via miRNA.

LncRNA AC007271.3 promotes cell proliferation, invasion, migration and inhibits cell apoptosis of OSCC via the Wnt/ß-catenin signaling pathway.

AIMS: Long noncoding RNA (lncRNA) AC007271.3 has been identified to be dysregulated in oral squamous cell carcinoma (OSCC) in our previous study. However, the precise role of AC007271.3 in OSCC remains unclear. In this study, we investigated the potential functions and the underlying mechanisms of AC007271.3 in OSCC. MATERIALS AND METHODS: The expression levels of AC007271.3 in OSCC tissues and cell lines were examined using RT-qPCR. The relationship between AC007271.3 level and clinicopathological characteristics was analyzed, and its association with patient prognosis was assessed by the Kaplan-Meier method. The biological function of AC007271.3 and its role in the development of OSCC through Wnt/ß-catenin signaling pathway were studied. KEY FINDINGS: We identified that AC007271.3 was up-regulated and positively correlated with advanced clinical stage, lymph node metastasis, poor histological differentiation and unfavorable prognosis. We explored the expression, function, and molecular mechanism of AC007271.3 in OSCC cells. Overexpression of AC007271.3 remarkably promoted cell proliferation in vitro and in vivo, induced cell migration, invasion and inhibited apoptosis in vitro, while knockdown of AC007271.3 attenuated cell proliferation, migration, invasion and induced apoptosis. Mechanistically, AC007271.3 overexpression substantially increased the expression of ß-catenin and the downstream target molecules CyclinD1, c-myc and Bcl-2, while silencing of AC007271.3 has the opposite effect. Rescued experiments showed that the ability to promote cell proliferation, migration, invasion and inhibiting apoptosis could be reversed when treated with the Wnt/ß-catenin pathway inhibitor. SIGNIFICANCE: Our data indicated that AC007271.3 could promote cell proliferation, invasion and inhibit cell apoptosis of OSCC via the Wnt/ß-catenin signaling pathway, which might provide a novel therapeutic approach for OSCC.