Project description:OBJECTIVES: To detect the expression levels of MLKL and p-MLKL, and explore its potential roles in inflammatory cell infiltration, angiogenesis, and bone destruction, in human and mouse periapical lesions. METHODS: Forty-six human periapical tissues, including periapical granulomas (PGs, n =26), radicular cysts (RCs, n =20), and eight healthy control tissues were collected. Samples were fixed and analyzed by HE staining, RNA-Seq, western blot, and immunohistochemical staining. A periapical lesion mouse model was induced by pulp exposure in the first lower molars of 15 C57BL/6J mice. After lesion induction, the mice were sacrificed on days 0, 21, and 35. Mandibles were harvested for microcomputed tomography scanning, histologic observation, immunohistochemistry, enzyme histochemistry, and double immunofluorescence analysis. Double immunofluorescence was utilized to assess the colocalization of phosphorylated MLKL (p-MLKL) with CD34, matrix metalloproteinase-9 (MMP-9), and Cathepsin K (CTSK) in human and mouse periapical lesions. RESULTS: RNA-Seq analysis showed that, in comparison with healthy gingiva tissues, MLKL was more significantly upregulated in periapical lesions (P-value < 0.05). Immunohistochemistry staining showed that, MLKL and p-MLKL were significantly overexpressed in the RC and PG groups compared with the control group (P-value < 0.05). However, the difference between the RC and PG groups was insignificant (P-value > 0.05). p-MLKL-positive cells were mainly lymphocytes, epithelial cells, and endothelial cells around the vascular wall. In mouse periapical lesions, the expression levels of p-MLKL were positively correlated with the bone defect area and tartrate-resistant acid phosphatase-positive (TRAP+) cell amounts (R2=0.4108, P-value < 0.05; R2=0.5668, P-value < 0.05, respectively). The double-labeling analysis showed that p-MLKL colocalized with CD34 and MMP-9 in human samples, and with CTSK adjacent to the bone in mouse periapical lesions. CONCLUSION: MLKL and p-MLKL were overexpressed in human periapical lesions. p-MLKL exhibited a close relationship with angiogenesis and alveolar bone resorption.
Project description:Apical periodontitis (AP) is a painful inflammatory disease resulting from tooth infection that affects millions worldwide with a marked impact on quality of life and is accompanied by bone loss surrounding the affected tooth. There is growing evidence that the nociceptive fibers densely innervating teeth regulate the disease progression, in addition to their sensorial function. We hypothesized that nociceptors regulate the transcriptomic profile of the periapical osteolytic lesion in a mouse model of AP. Male control (Nav1.8 cre+/-) and nociceptor-ablated (Nav1.8cre+/- DTAlox+/-) mice were generated and underwent pulp exposure procedures on all 4 first molars and at 8 weeks of age. At either 0, 7, or 14 days after pulp exposure, periapical tissues were dissected from mice (n=3-4/strain/time point). Total RNA was extracted from the pooled periapical lesions from each animal and submitted for total RNA sequencing and bioinformatic analysis. We found that pulp exposure triggers the differential expression of hundreds of genes within the periapical lesion over the course of infection with marked differences between in both control and mice with nociception ablation. Importantly, at 14 days post pulp-exposure, 422 genes were differentially expressed between nociceptor-ablated and control mice with greater enrichment of biological processes related to inflammation, specifically immune cell chemotaxis and migration, compared to control mice. Among these inflammatory markers, TNFα, IL-1α, and IL-1β, that are known to play a crucial role in AP were significantly upregulated in nociceptor-ablated mice. In conclusion, nociceptor-ablation regulates the transcriptomic profile of periapical lesions in a mouse model of AP, shifting the gene expression profile to a greater enrichment of inflammatory genes, suggesting nociceptors play a role in the kinetics of the immune response. This newly uncovered neuro-immune axis and its mechanisms in AP can potentially be an important therapeutic target for the treatment of this prevalent disease.
Project description:Chronic apical periodontitis (CAP) is a unique dynamic interaction between microbial invasions and host defense mechanisms, resulting in bone absorption, infiltration of immune cells and sporadic periapical granuloma. In this study, we constituted a single-cell atlas for 26,737 high-quality cells from hyperplastic periapical tissue using single-cell RNA sequencing. Identifying cell types and signatures at the single-cell level might generate novel insights into the clinical pathogenesis of CAP. A histological analysis to verify the gene signatures of nonimmune cells was combined with immunohistochemistry staining. We then discovered the diversity and heterogeneity of nonimmune cells in regional CAP lesions. The temporal profiling of genomic alterations from common CAP to typical periapical granuloma provided predictions for key transcription factors and biological processes. Our study also inferred that the marked shift of inflammatory cytokines, chemokines, proteases and growth factors enables the initiation of polymorphic cell differentiation, lymphangiogenesis and angiogenesis during CAP.
Project description:Recently, L-lactic acid was identified as a unique metabolite in periapical granulomas. However, the biological roles of this metabolite in this lesion were unknown. Therefore, we aimed to investigate the inflammatory effect of L-lactic acid on peripheral blood mononuclear cells (PBMCs).
Project description:To understand the roles of molecules in functional differentiation among adult human tissues, we performed a systematic survey of mRNA, protein, and protein phosphorylation as well as miRNA expression, in three tissues: cerebellum, prefrontal cortex and liver. We found that tissues were clearly distinct from one another at all levels. Furthermore, our results showed that miRNA differently expressed between tissues have significant, but modest effect on expression of mRNA and somewhat stronger effect on expression of proteins among the tissues. Notably, miRNA preferentially targeted gene regulators, transcription factors and kinases, in all three tissues studied. Following this path, we found that miRNA effect was further amplified through expression changes of target transcription factors and kinases, leading to further changes in their targets’ expression and phosphorylation levels. Importantly, miRNA regulation leads to reduced, rather than increased gene expression variation among individuals between two brain regions. These observations uncover the complexity of miRNA regulatory interactions and are compatible with suggested role of miRNA in gene expression canalization.
Project description:To explore the role of miRNAs in gastric cancer, miRNA microarray profiling in 28 pairs of gastric cancer tissues and the matched normal mucosal tissues were performed.
Project description:miRNA played an important role in the process of carcinogenesis in HBV related hepatocellular carcinoma. Therefore, we performed miRNA microarray to evaluate the miRNAs that expressed differentially between HCC tumor versus non-tumor liver tissues.
Project description:MicroRNA (miRNA/miR) miR526b and miR655 overexpressed tumor cell-free secretions promote breast cancer phenotypes in the tumor microenvironment (TME). However, the mechanisms of miRNA regulating TME have never been investigated. With mass spectrometry analysis of MCF7-miRNA-overexpressed versus miRNA-low MCF7-Mock tumor cell secretomes, we identified 34 novel secretory proteins coded by eight genes YWHAB, TXNDC12, MYL6B, SFN, FN1, PSMB6, PRDX4, and PEA15 those are differentially regulated. We used bioinformatic tools and systems biology approaches to identify these markers’ role in breast cancer. Gene ontology analysis showed that the top functions are related to apoptosis, oxidative stress, membrane transport, and motility, supporting miRNA-induced phenotypes. These secretory markers expression is high in breast tumors, and a strong positive correlation exists between upregulated markers’ mRNA expressions with miRNA cluster expression in luminal A breast tumors. Gene expression of secretome markers is higher in tumor tissues compared to normal samples, and immunohistochemistry data supported gene expression data. Moreover, both up and downregulated marker expressions are associated with breast cancer patient survival. miRNA regulates these marker protein expressions by targeting transcription factors of these genes. Premature miRNA (pri-miR526b and pri-miR655) are established breast cancer blood biomarkers. Here we report novel secretory markers upregulated by miR526b and miR655 (YWHAB, MYL6B, PSMB6, and PEA15) are significantly upregulated in breast cancer patients’ plasma, and are potential breast cancer biomarkers.