The immunohistochemical profile of basal cell nevus syndrome-associated and sporadic odontogenic keratocysts: a systematic review and meta-analysis

The Stem Cell Expression Profile of Odontogenic Tumors and Cysts: A Systematic Review and Meta-Analysis

BACKGROUND

Stem cells have been associated with self-renewing and plasticity and have been investigated in various odontogenic lesions in association with their pathogenesis and biological behavior. We aim to provide a systematic review of stem cell markers' expression in odontogenic tumors and cysts.

METHODS

The literature was searched through the MEDLINE/PubMed, EMBASE via OVID, Web of Science, and CINHAL via EBSCO databases for original studies evaluating stem cell markers' expression in different odontogenic tumors/cysts, or an odontogenic disease group and a control group. The studies' risk of bias (RoB) was assessed via a Joanna Briggs Institute Critical Appraisal Tool. Meta-analysis was conducted for markers evaluated in the same pair of odontogenic tumors/cysts in at least two studies.

RESULTS

29 studies reported the expression of stem cell markers, e.g., SOX2, OCT4, NANOG, CD44, ALDH1, BMI1, and CD105, in various odontogenic lesions, through immunohistochemistry/immunofluorescence, polymerase chain reaction, flow cytometry, microarrays, and RNA-sequencing. Low, moderate, and high RoBs were observed in seven, nine, and thirteen studies, respectively. Meta-analysis revealed a remarkable discriminative ability of SOX2 for ameloblastic carcinomas or odontogenic keratocysts over ameloblastomas.

CONCLUSION

Stem cells might be linked to the pathogenesis and clinical behavior of odontogenic pathologies and represent a potential target for future individualized therapies.

Decoding a gene expression program that accompanies the phenotype of sporadic and Basal Cell Nevus Syndrome-associated odontogenic keratocyst

BACKGROUND

Odontogenic keratocyst (OKC) is characterized by local aggressive behavior and a high recurrence rate, as well as the potential to develop in association with the Basal Cell Nevus Syndrome (BCNS). The aim of this study was to decode the gene expression program accompanying OKC phenotype.

METHODS

150-bp paired-end RNA-sequencing was applied on 6 sporadic and 6 BSCN-associated whole-tissue OKC samples in comparison to 6 dental follicles, coupled to bioinformatics and complemented by immunohistochemistry.

RESULTS

2,654 and 2,427 differentially expressed genes were captured to characterize the transcriptome of sporadic and BCNS-associated OKCs, respectively. Gene ontologies (GOs) related to "epidermis/skin development" and "keratinocyte/epidermal cell differentiation" were enriched among the upregulated genes (KRT10, NCCRP1, TP63, GRHL3, SOX21), while "extracellular matrix (ECM) organization" (ITGA5, LOXL2) and "odontogenesis" (MSX1, LHX8) GOs were overrepresented among the downregulated genes in OKC. Interestingly, upregulation of various embryonic stem cells (ESCs) markers (EPHA1, SCNN1A) and genes committed in cellular reprogramming (SOX2, KLF4, OVOL1, IRF6, TACSTD2, CDH1) was found in OKC. These findings were highly shared between sporadic and BCNS-associated OKCs. Immunohistochemistry verified SOX2, KLF4, OVOL1, IRF6, TACSTD2/TROP2, CDH1/E-cadherin, and p63 expression predominantly in the OKC suprabasal epithelial layers.

CONCLUSION

The OKC transcriptomic profile is characterized by a prominent epidermal and dental epithelial fate, a repressed dental mesenchyme fate combined with deregulated ECM organization, and enhanced stemness gene signatures. Thus, we propose a developed epidermis-like phenotype in the OKC suprabasal epithelial cells, established in parallel to a significant upregulation of marker genes related to ESCs and cellular reprogramming. This article is protected by copyright. All rights reserved.