Molecular alterations in odontogenic keratocysts as potential therapeutic targets

Can CAPRIN-1 Be Responsible for the Recurrence Potential of Odontogenic Keratocysts?

Objectives

The purpose of this retrospective study is to compare dentigerous cysts and odontogenic keratocysts for cytoplasmic activation/proliferation - associated protein-1 antibodies via immunohistochemical staining to obtain a new perspective about the specific behavioural characteristics of odontogenic keratocysts at the molecular level.

Material and Methods

Forty dentigerous cysts (DC) and forty odontogenic keratocysts (OKC) tissue samples were examined using immunohistochemical staining to detect cytoplasmic activation/proliferation - associated protein-1 (CAPRIN-1) antibodies. Nuclear and/or cytoplasmic staining was evaluated as "positive". Cell staining rate (%) and cell staining intensity were determined, and a staining intensity distribution (SID) score was calculated for each sample. Cases were considered "negative" if they showed no staining for CAPRIN-1 antibodies, thus were given a SID score of zero. According to the SID scores, the expression levels were rated as negative, mild, moderate, or high.

Results

Of 80 samples, 16 that could adversely affect immunohistochemical evaluation were excluded. Ten negative, 21 positive and three negative, 30 positive CAPRIN-1 expressions were observed in DC and OKC groups, respectively. The difference between the negative and positive cases within groups was significant only in the OKC group (P = 0.000). The SID score range and mean were 0 to 160 and 31.1 (SD 35.7) for DC and 0 to 160 and 57.3 (SD 42.3) for OKC groups. CAPRIN-1 expression was significantly higher in the OKC group (P = 0.043).

Conclusions

The molecular basis for increased mitotic activity, high recurrence rates or presence of satellite cysts in odontogenic keratocysts may be attributed to the expression of cytoplasmic activation/proliferation - associated protein-1.

Unveiling metabolic changes in marsupialized odontogenic keratocyst: A pilot study

OBJECTIVE

We aimed to assess which metabolic pathways would be implicated in the phenotypic changes of the epithelial lining of odontogenic keratocyst after marsupialization, comparing pre- and post-marsupialized lesions with adjacent oral mucosa.

MATERIALS AND METHODS

Eighteen formalin-fixed and paraffin-embedded tissues from six subjects were divided into three paired groups: odontogenic keratocyst pre- (n = 6) and post-marsupialization (n = 6), and adjacent oral mucosa (n = 6). The metabolic pathways found in these groups were obtained by high-performance liquid chromatography-mass spectrometry-based untargeted metabolomics performed.

RESULTS

Through putative metabolite annotation followed by pathway enrichment and predictive analysis with automated algorithms (Mummichog and Gene Set Enrichment Analysis), we found differences in many cellular processes that may be involved in inflammation, oxidative stress response, keratinocyte-basal membrane attachment, differentiation, and proliferation functions, all relevant to odontogenic keratocyst pathobiology and the phenotype acquired after marsupialization.

CONCLUSION

Our study was able to identify several metabolic pathways potentially involved in the metaplastic changes induced by marsupialization of odontogenic keratocysts. An improved comprehension of this process could pave the way for the development of targeted therapies.

Deregulation of desmosomal proteins and extracellular matrix proteases in odontogenic keratocyst

OBJECTIVE

Odontogenic keratocyst (OKC) is a benign lesion that tends to recur after surgical treatment. In an attempt to clarify the molecular basis underlining the OKC pathobiology, we aimed to analyze its proteomic profile.

MATERIALS AND METHODS

We compared the proteomic profiles of five OKC and matched normal oral mucosa by using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Then, we performed enrichment analysis and a literature search for the immunoexpression of the proteomics targets.

RESULTS

We identified 1,150 proteins and 72 differently expressed proteins (log2 fold change ≥ 1.5; p < .05). Twenty-seven peptides were exclusively detected in the OKC samples. We found 35 enriched pathways related to cell differentiation and tissue architecture, including keratinocyte differentiation, keratinization, desmosome, and extracellular matrix (ECM) organization and degradation. The immunoexpression information of 11 out of 50 proteins identified in the enriched pathways was obtained. We found the downregulation of four desmosomal proteins (JUP, PKP1, PKP3, and PPL) and upregulation of ECM proteases (MMP-2, MMP-9, and cathepsins).

CONCLUSIONS

Proteomic analysis strengthened the notion that OKC cells have a similar proteomic profile to oral keratinocytes. Contextual investigation of the differentially expressed proteins revealed the deregulation of desmosome proteins and ECM degradation as important alterations in OKC pathobiology.

Teratocarcinoma-derived growth factor-1 (Cripto-1) is overexpressed in epithelial odontogenic lesions displaying more aggressive behaviour

PURPOSE

Cripto-1 also known as teratoma-derived growth factor 1 (TDGF-1) belongs to the EGF-CFC family of growth factor-like molecules. Cripto-1 is involved with embryonic development and not expressed in adult tissue, but some tumours are accompanied by reactivation.

METHODS

The aim of this study was to evaluate the immunohistochemical expression of Cripto-1 in most common odontogenic cysts and tumours. Thirty ameloblastomas, 30 keratocysts, 30 dentigerous cysts and two ameloblastic carcinomas were evaluated using the polymeric immunoperoxidase technique. Immunohistochemical expressions were analysed by the IRS (immunoreactive score). Statistical analyses were performed by the Kruskal-Wallis and Mann-Whitney tests (p ≤ 0.05).

RESULTS

Age ranged from 9 to 75 years old, with a prevalence of females (n = 49/53.3%). The mandible was the most affected anatomical site (n = 69/75.0%). Cripto-1 immunoexpression was observed in all ameloblastoma, keratocyst and ameloblastic carcinoma cases, although nine dentigerous cyst cases (30%) were negative. Expression scores were higher in ameloblastoma, keratocyst and ameloblastic carcinoma cases (median ranging from 8 to 11) when compared with dentigerous cyst cases (median of 2), with a statistically significant difference (p < 0.001).

CONCLUSIONS

Cripto-1 is critically important in the progression of several tumours since it is related to significant cell survival and differentiation pathways. The high expression of Cripto-1 in more aggressive odontogenic lesions suggests that this molecule may be involved in the activation of important pathways related to the etiopathogenesis of these lesions.

SOX2 and BCL-2 Expressions in Odontogenic Keratocyst and Ameloblastoma

Background

The purpose of this experimental study was to compare the immunohistochemical expression of SOX2 and BCL-2 in Odontogenic Keratocyst (OKC) and Ameloblastoma (AB) specimens, and to identify a possible correlation in their expression.

Material and Methods

Immunohistochemical analysis was performed to evaluate SOX2 and BCL-2 expression in OKC (n = 20) and AB (n = 20). The immunoexpression was analyzed by a quantitative and qualitative scoring system. The comparison between the immunoexpression of SOX 2 and BCL-2 was assessed by the Mann-Whitney U-test. Spearman’s correlation coefficient evaluated the correlation between SOX2 and BCL-2 expressions.

Results

SOX2 and BCL-2 expression was observed in all specimens of OKC in the full thickness of the epithelium lining. SOX2 immunostaining was higher in OKC, in comparison with AB samples (P<0.05). BCL-2 immunostaining between OKC and AB was not statistically significant. There was no significant correlation between SOX2 and BCL-2 in OKC and AB specimens.

Conclusions

SOX2 and BCL-2 expressions in OKC may suggest their relationship with the biological behavior of this lesion, and the higher expression of SOX2 might be an upstream influence on the Hh signaling pathway.

Key words:Odontogenic keratocyst; Ameloblastoma; Odontogenic tumor; SOX2; BCL-2.