ODAM promotes junctional epithelium-related gene expression via activation of WNT1 signaling pathway in an ameloblast-like cell line ALC

Comparative Immunohistochemical Analysis of Craniopharyngioma and Ameloblastoma: Insights into Odontogenic Differentiation

BACKGROUND AND OBJECTIVES

Histopathological similarities between craniopharyngioma (CP) and ameloblastoma (AB) have long been recognized, particularly the shared features of palisading columnar epithelium and stellate reticulum-like areas. This study aimed to investigate potential odontogenic differentiation in CP akin to AB using immunohistochemical odontogenic markers.

METHODS

We analyzed AMELX, ODAM, and CK19 expression in 44 cases (20 CP and 24 AB).

RESULTS

While AMELX and ODAM showed diffuse strong positive expression in both tumors with no significant statistical differences, CK19 expression was notably higher in CP.

CONCLUSION

The markers AMELX and ODAM associated with odontogenic differentiation exhibited similar profiles in both tumors due to shared similar embryological origins. Notably, CK19, a biomarker of odontogenic epithelium, showed even higher expression, suggesting distinct pathways. These findings offer insights into tumor biology and may aid in diagnostic and therapeutic approaches.

The secretory leukocyte protease inhibitor (SLPI) in pathophysiology of non-communicable diseases: Evidence from experimental studies to clinical applications

Non-communicable diseases (NCDs) are a worldwide health issue because of their prevalence, negative impacts on human welfare, and economic costs. Protease enzymes play important roles in viral and NCD diseases. Slowing disease progression by inhibiting proteases using small-molecule inhibitors or endogenous inhibitory peptides appears to be crucial. Secretory leukocyte protease inhibitor (SLPI), an inflammatory serine protease inhibitor, maintains protease/antiprotease balance. SLPI is produced by host defense effector cells during inflammation to prevent proteolytic enzyme-induced tissue damage. The etiology of noncommunicable illnesses is linked to SLPI's immunomodulatory and tissue regeneration roles. Disease phases are associated with SLPI levels and activity changes in regional tissue and circulation. SLPI has been extensively evaluated in inflammation, but rarely in NCDs. Unfortunately, the thorough evaluation of SLPI's pathophysiological functions in NCDs in multiple research models has not been published elsewhere. In this review, data from PubMed from 2014 to 2023 was collected, analysed, and categorized into in vitro, in vivo, and clinical studies. According to the review, serine protease inhibitor (SLPI) activity control is linked to non-communicable diseases (NCDs) and other illnesses. Overexpression of the SLPI gene and protein may be a viable diagnostic and therapeutic target for non-communicable diseases (NCDs). SLPI is also cytoprotective, making it a unique treatment. These findings suggest that future research should focus on these pathways using advanced methods, reliable biomarkers, and therapy approaches to assess susceptibility and illness progression. Implications from this review will help pave the way for a new therapeutic target and diagnosis marker for non-communicable diseases.

A novel junctional epithelial cell line, mHAT-JE01, derived from incisor epithelial cells

OBJECTIVES

Junctional epithelium (JE) connects the tooth surface and gingival epithelium and adheres directly to the tooth enamel. JE plays an important role as a barrier preventing the invasion of exogenous bacteria and substances. However, the cellular characteristics of this epithelium have not been adequately described, because no useful in vitro experimental model exists for JE.

METHODS

We generated a novel JE cell line, mHAT-JE01, using naturally immortalized dental epithelium derived from incisor labial cervical cells and by selecting cells that adhered to apatite. mHAT-JE01 was characterized by immunohistochemistry and quantitative reverse transcription-polymerase chain reaction and compared with the gingival epithelial cell line, mOE-PE01.

RESULTS

The mHAT-JE01 cells had a higher capacity for producing JE-specific markers than oral mucous epithelial cells. In addition, the presence of lipopolysaccharides from Porphyromonas gingivalis downregulated the expression of JE protein markers in mHAT-JE01 cells.

CONCLUSIONS

This cell line is stable and presents the opportunity to characterize JE efficiently, which is essential for the prevention and treatment of periodontal disease.

The versatile roles of odontogenic ameloblast-associated protein in odontogenesis, junctional epithelium regeneration and periodontal disease

Junctional epithelium (JE) is a vital epithelial component which forms an attachment to the tooth surface at the gingival sulcus by the adhesion of protein complexes from its basal layer. Disruption of the JE is associated with the development of gingivitis, periodontal disease, and alveolar bone loss. Odontogenic ameloblast-associated (ODAM) is comprised of a signal peptide and an ODAM protein with 12 putative glycosylation sites. It is expressed during odontogenesis by maturation stage ameloblasts and is incorporated into the enamel matrix during the formation of outer and surface layer enamel. ODAM, as a secreted protein which is accumulated at the interface between basal lamina and enamel, mediates the adhesion of the JE to the tooth surface; and is involved with extracellular signalling of WNT and ARHGEF5-RhoA, as well as intracellular signalling of BMP-2-BMPR-IB-ODAM. ODAM is also found to be highly expressed in salivary glands and appears to have implications for the regulation of formation, repair, and regeneration of the JE. Bioinformatics and research data have identified the anti-cancer properties of ODAM, indicating its potential both as a prognostic biomarker and therapeutic target. Understanding the biology of ODAM will help to design therapeutic strategies for periodontal and dental disorders.

Interleukin-1β regulates odontogenic ameloblast-associated protein gene transcription in human gingival epithelial cells

Junction epithelium (JE) is located apical to the bottom of the gingival sulcus and binds enamel to hemidesmosomes to protect the periodontal tissue from bacterial infection. Function of odontogenic ameloblast-associated protein (ODAM) is suggested by its expression sites (JE and maturation stage ameloblasts) to be involved in the adhesion between the JE and enamel, and odontogenesis. To analyze the changes in ODAM gene and protein expressions in inflamed gingiva, Ca9-22 gingival epithelial cells were stimulated with 1 ng/ml interleukin-1β (IL-1β) for 3-24 h, and ODAM mRNA and protein levels were analyzed by real-time PCR and Western blotting. Luciferase (LUC) constructs were made ligating various lengths of human ODAM gene promoters and performed LUC analyses in Ca9-22 cells. Gel shift and chromatin immunoprecipitation (ChIP) assays were performed. IL-1β induced ODAM mRNA and protein levels at 6-24 h. IL-1β increased LUC activities of the ODAM gene promoter constructs from - 85 to - 950. These activities were blocked by protein kinase A, tyrosine kinase, mitogen-activated protein (MAP) kinase kinase and phosphoinositide 3-kinase inhibitors. Gel shift and ChIP assays showed that IL-1β induced CCAAT/enhancer-binding protein (C/EBP) β and Yin Yang1 (YY1) binding to C/EBP1, 2, 3, and YY1 elements. These data indicate that IL-1β stimulates ODAM gene transcription mediated through C/EBP1, C/EBP2, C/EBP3, and YY1 elements in the human ODAM gene promoter.

CircRNA CircZMYM4 inhibits the growth and metastasis of lung adenocarcinoma via the miR-587/ODAM pathway

Circular RNAs (circRNAs) are known to regulate tumorigenesis. In this study, circRNAs microarray was used to analyze the circRNA expression in lung adenocarcinoma (LUAD) tissues, and CircRNA zinc finger MYM-type containing 4(circZMYM4) was selected for further analysis. In this study, we detected circZMYM4 expression in LUAD specimens and cell lines using RT-PCR. The expression of circZMYM4 was further verified in the GEO datasets and TCGA datasets. Gain-of-function and loss-of-function experiments were used to analyze the effects of circZMYM4 on LUAD in vivo and in vitro. The relationship between miR-587 and circZMYM4 or ODAM was predicted by bioinformatics tools and confirmed using dual-luciferase reporter assays and RNA-pull down. We found that circZMYM4 was distinctly down-regulated in LUAD tissues and cell lines. Functional assays revealed that circZMYM4 overexpression suppressed LUAD cell proliferation, metastasis and suppressed apoptosis, while miR-587 overexpression could weaken these effects. Importantly, circZMYM4 upregulated ODAM expression via sponging miR-587 to suppress LUAD progression. ODAM knockdown could reverse the repressive effect of circZMYM4 overexpression on cell proliferation, migration and invasion abilities. Overall, circZMYM4 regulates the miR-587/ODAM axis to suppress LUAD progression, which may become a potential biomarker and therapeutic target.

Transcriptional regulation of human odontogenic ameloblast-associated protein gene by tumor necrosis factor-α

OBJECTIVE

Odontogenic ameloblast-associated protein (ODAM) is produced by maturation stage ameloblasts and junctional epithelium (JE). The function of ODAM is thought to be involved in the attachment of teeth and JE. To elucidate transcriptional regulation of human ODAM gene in inflamed gingiva, we have analyzed the effects of TNF-α on the expression of ODAM gene in Ca9-22 and Sa3 gingival epithelial cells.

MATERIALS AND METHODS

Total RNAs were extracted from Ca9-22 and Sa3 cells after stimulation by TNF-α (10 ng/ml). ODAM mRNA and protein levels were analyzed by qPCR and Western blotting. Luciferase (LUC) analyses were performed using LUC constructs inserted in various lengths of ODAM gene promoter. Gel shift and chromatin immunoprecipitation (ChIP) assays were carried out.

RESULTS

TNF-α increased ODAM mRNA and protein levels at 3 to 24 h. TNF-α induced LUC activities of the ODAM gene promoter constructs, and the activities were inhibited by protein kinase A, tyrosine kinase, MEK1/2, PI3-kinase and NF-κB inhibitors. Gel shift and ChIP assays revealed that TNF-α increased CCAAT/enhancer-binding protein (C/EBP) β and Yin Yang1 (YY1) binding to three kinds of C/EBPs and YY1 elements.

CONCLUSION

These results demonstrate that TNF-α stimulates ODAM gene transcription via C/EBPs and YY1 elements in the human ODAM gene promoter.