No abstract

Dental tissue-derived mesenchymal stem cells (MSCs) are a reliable cell source for dental tissue regeneration. However, the molecular mechanisms underlying the directed differentiation of MSCs remain unclear; thus, their use is limited. The histone demethylase, lysine (K)-specific demethylase 4B (KDM4B), plays critical roles in the osteogenic commitment of MSCs by up-regulating distal-less homeobox 2 (DLX2) expression. The DLX2 gene is highly expressed in dental tissue-derived MSCs but the roles of DLX2 in osteogenesis are unclear. Here, we investigate DLX2 function in stem cells from apical papilla (SCAPs). We found that, in vitro, DLX2 expression was up-regulated in SCAPs by adding BMP4 and by inducing osteogenesis. The knock-down of DLX2 in SCAPs decreased alkaline phosphatase (ALP) activity and mineralization. DLX2 depletion affected the mRNA expression of ALP, bone sialoprotein (BSP) and osteocalcin (OCN) and inhibited SCAP osteogenic differentiation in vitro. Over-expression of DLX2 enhanced ALP activity, mineralization and the expression of ALP, BSP and OCN in vitro. In addition, transplant experiments in nude mice confirmed that SCAP osteogenesis was triggered when DLX2 was activated. Furthermore, DLX2 expression led to the expression of the key transcription factor, osterix (OSX) but not to the expression of runt-related transcription factor 2 (RUNX2). Taken together, these results indicate that DLX2 is stimulated by BMP signaling and enhances SCAP osteogenic differentiation by up-regulating OSX. Thus, the activation of DLX2 signaling might improve tissue regeneration mediated by MSCs of dental origin. These results provide insight into the mechanism underlying the directed differentiation of MSCs of dental origin.

Lymphocyte infiltrates have been observed in the microenvironment of oral cancer; however, little is known about whether the immune response of the lymphocyte infiltrate affects tumor biology. For a deeper understanding of the role of the infiltratinglymphocytes in oral squamous cell carcinoma (OSCC), we characterized the lymphocyte infiltrate repertoires and defined their features. Immunohistochemistry revealed considerable T and B cell infiltrates and lymphoid follicles with germinal center-like structures within the tumor microenvironment. Flow cytometry demonstrated that populations of antigen-experienced CD41 and CD81 cells were present, as well as an enrichment of regulatory T cells; and T cells expressing programmed death-1 (PD-1) and T cell Ig and mucin protein-3 (Tim-3), indicative of exhaustion, within the tumor microenvironment. Characterization of tumorinfiltrating B cells revealed clear evidence of antigen exposure, in that the cardinal features of an antigen-driven B cell response were present, including somatic mutation, clonal expansion, intraclonal variation and isotype switching. Collectively, our results point to an adaptive immune response occurring within the OSCC microenvironment, which may be sustained by the expression of specific antigens in the tumor.Oral cancer is the sixth most common cancer in the world, most of which is oral squamous cell carcinoma (OSCC), accounting for 3% of all malignancies and increasing by 275,000 new cases per year.1,2 Oral cancer is life-threatening because of its invasion of critical structures responsible for speaking, swallowing, and respiration. 3 The treatment of oral cancer has advanced considerably from surgery to a comprehensive sequential treatment that include surgery in combination with chemoradiotherapy; however, the 5-year survival rate has not significantly improved in recent decades, primarily because of its extreme malignancy, including local metastasis, and high recurrence potential. 3,4 Thus, more substantial efforts have stimulated in developing more effective treatments in order to improve the survival rate. Due to the progress in the field of tumor immunology, immunotherapy emerges as a promising option. 5,6The immune response between host and tumor is extremely complex. The function of immune system is to eliminate alien cells; however within the tumor microenvironment, tumor cells escape the immune surveillance and

Natural and synthetic progestins may pose a threat to wild fish populations living in receiving waters. In this study, the effects of norethindrone (NET) on the sex differentiation of zebrafish (Dario renio) and the mechanisms underlying these effects were investigated. Juvenile zebrafish (20 days post fertilization, pdf) were exposed to environmentally relevant concentrations (5, 50, 500, and 1000 ng L) for 45 d. Sex ratio of the NET-exposed populations, the histology of the gonads and the transcriptional profile of the regulatory genes involved in sex differentiation and steroidogenesis were examined. The results showed that a significantly higher ratio of male/female was induced in the zebrafish populations exposed to NET at concentrations higher than 32.3 ng L. Exposure to NET caused acceleration of sexual mature in males and a delay in ovary maturation in female zebrafish. Among the genes regulating sexual differentiation, transcripts of Dmrt1 showed a dose-dependent increase while transcripts of Figa and Fox12 showed a dose-dependent decrease in response to exposure to NET. For genes regulating the steroidogenesis, the expressions of Cyp11a1, Cyp17, Cyp19a1a, and Cyp11b were significantly down-regulated by exposure to NET, while Hsd17b3 expression was significantly up-regulated by exposure to NET at 421.3 and 892.9 ng L. For the receptor genes in the gonads, the transcriptional expression of Pgr, Ar, and Mr was significantly up-regulated at 421.3 and 892.9 ng L of NET. For genes involved in the hypothalamic-pituitary axis, the transcriptional expression of Gnrh3 and Pomc was significantly up-regulated by exposure to NET with the exception for Gnrh3 at 4.2 ng L. The results demonstrated that exposure to NET at the juvenile stage could affect gonad differentiation and sex ratio, which might be accounted for by the alterations of the transcriptional expressions of genes along the hypothalamic-pituitary-gonadal (HPG) and hypothalamic-pituitary-adrenal (HPA) axes.

The adipogenic differentiation of adipose tissue-derived mesenchymal stem cells (ADSCs) is a critical issue in many obesity-related disorders. Cytidine-cytidine-adenosineadenosine-thymidine (CCAAT) enhancer binding protein α (CEBP-α) and peroxisome proliferator-activated receptor-γ are two important lipogenic and adipogenic transcription factors and markers in adipogenic differentiation. Noncoding RNAs participate in adipogenic differentiation. The long noncoding RNA (lncRNA) H19 is related to multiple cellular differentiation, including adipogenic differentiation; however, its function and precise molecular mechanism in human ADSCs (hADSCs) adipogenic differentiation are unclear. microRNAs that were differentially expressed in adipogenic differentiation and could be targeted by H19 were screened and selected; the regulation and interaction between H19 and miR-30a were verified. The interaction between miR-30a and predicted downstream target C8orf4 was validated. The dynamic effects of H19 and miR-30a on C8orf4 messenger RNA (mRNA) expression and protein and adipogenic differentiation were evaluated. miR-30a negatively regulated H19 with each other through direct binding. As predicted by TargetScan and verified using luciferase reporter gene assays, miR-30a directly bound to the 3′-untranslated region of C8orf4 to inhibit its expression; H19 knockdown suppressed while miR-30a inhibition promoted the mRNA expression and the protein levels of C8orf4 and adipogenic differentiation; the effect of H19 knockdown could be partially reversed by miR-30a inhibition. The lncRNA H19 serves as a competing endogenous RNA (ceRNA) for miR-30a to augment miR-30a downstream target C8orf4, therefore modulating adipogenic differentiation in hADSCs.From the perspective of lncRNA-miRNA-mRNA regulation, we provided a novel regulatory mechanism of hADSCs adipogenic differentiation. K E Y W O R D S adipogenic differentiation, C8orf4, human adipose tissue-derived mesenchymal stem cells, lncRNA H19, miR-30a

Oral tongue squamous cell carcinoma (OTSCC) is one of the most common head and neck cancers. Innate or acquired resistance to cisplatin, a standard chemotherapy agent for OTSCC, is common in patients with OTSCC. Understanding the molecular basis for cisplatin chemoresistance in OTSCC cells may serve as a basis for identification of novel therapeutic targets. Podocalyxin (PODXL) has been found critical for malignant progression in a variety of cancers. Bmi1 has recently been found to induce cell apoptosis and cisplatin chemosensitivity in OTSCC cells. In this study, we explored the interaction between PODXL and Bmi1 in OTSCC cells, and assessed its impact on OTSCC cell chemoresistance to cisplatin. PODXL and/or Bmi1 were stably overexpressed or knocked down in SCC-4 and Tca8113 human OTSCC cells. Overexpression of PODXL in both cell lines markedly elevated the expression level of Bmi1 and the half maximal inhibitory concentration (IC50) of cisplain and reduced cisplatin-induced cell apoptosis, which was abolished by knockdown of Bmi1 or a selective focal adhesion kinase (FAK) inhibitor. On the other hand, knockdown of PODXL significantly decreased the Bmi1 expression level and cisplatin IC50 and increased cisplatin-induced cell apoptosis, which was completely reversed by overexpression of Bmi1. While overexpression and knockdown of PODXL respectively increased and decreased the FAK activity, Bmi1 showed no significant effect on the FAK activity in OTSCC cells. In addition, overexpression of PODXL markedly elevated the stability of Bmi1 mRNA, which was abolished by a selective FAK inhibitor. In conclusion, this study provides the first evidence that PODXL up-regulates the expression level of Bmi1 in OTSCC cells by increasing the stability of Bmi1 mRNA through a FAK-dependent mechanism; this effect leads to enhanced cisplatin chemoresistance in OTSCC cells. This study adds new insights into the molecular mechanisms underlying OTSCC chemoresistance.

Oral squamous cell carcinoma (OSCC) is a type of malignancy with high mortality, leading to poor prognosis worldwide. However, the molecular mechanisms underlying OSCC carcinogenesis have not been fully understood. Recently, the discovery and characterization of long non-coding RNAs (lncRNAs) have revealed their regulatory importance in OSCC. Abnormal expression of lncRNAs has been broadly implicated in the initiation and progress of tumors. In this review, we summarize the functions and molecular mechanisms regarding these lncRNAs in OSCC. In addition, we highlight the crosstalk between lncRNA and tumor microenvironment (TME), and discuss the potential applications of lncRNAs as diagnostic and prognostic tools and therapeutic targets in OSCC. Notably, we also discuss lncRNA-targeted therapeutic techniques including CRISPR-Cas9 as well as immune checkpoint therapies to target lncRNA and the PD-1/PD-L1 axis. Therefore, this review presents the future perspectives of lncRNAs in OSCC therapy, but more research is needed to allow the applications of these findings to the clinic.

Oral verrucous carcinoma (OVC) is a verrucous variant of oral cavity squamous carcinoma (OSCC). The expression of miRNA from OVC and OSCC including their matched normal oral mucosa tissues was profiled through the Affymetrix GeneChip miRNA Arrays. TargetScan and miRanda databases were used to predict the target gene of miRNA-195. The quantitative real-time PCR was applied to validate the expression of miRNA-195. The expression of CDK6 was investigated by the quantitative real-time PCR and immunohistochemistry. In this study, a total of 23 and 35 differentially expressed miRNAs were identified in OVC and OSCC, respectively. Moreover, 44 miRNAs were differentially expressed between OSCC and OVC. In addition, miRNA-195 was significantly decreased in both OVC and OSCC compared to normal oral mucosa. Target gene prediction demonstrated that CDK6 was a potential target gene of miRNA-195. In the quantitative real-time PCR, miR-195 was decreased in OVC and OSCC, which was consistent with the result of miRNA chip analysis. CDK6 was increased in OVC and OSCC, which was opposite to the expression of miRNA-195. In conclusion, miRNA-195 could be the potential diagnosis biomarker and therapy target of OVC.