Expression of cell cycle and apoptosis-related proteins in sporadic odontogenic keratocysts and odontogenic keratocysts associated with the nevoid basal cell carcinoma syndrome

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.

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

OBJECTIVES

To provide a systematic review of the literature on studies comparing the immunoprofile of nevoid basal cell carcinoma syndrome (BCNS)-associated and sporadic odontogenic keratocysts (OKCs), in order to identify markers that could accurately distinguish the two OKC subtypes.

MATERIALS AND METHODS

We searched MEDLINE/Pubmed, Web of Science, EMBASE via OVID, and grey literature for publications until December 28th, 2019, that compared the immunohistochemical expression of the two OKC subtypes. The studies were qualitatively assessed using the Critical Appraisal Tool for Case Series (Joana Briggs Institute). Sensitivity and specificity, positive and negative likelihood ratio, diagnostic odds ratio and area under the curve, and pooled estimates were calculated, using a random-effects model.

RESULTS

Seventy-one studies were qualitatively analyzed; 61 markers were evaluated in one study and 32 in ≥ 2 studies. Twenty-five studies reported differential expression of 29 markers in the form of higher number of positive cells or greater staining intensity usually in BCNS-associated OKCs. Meta-analysis for bcl-2, Cyclin D1, CD56, CK18, p53, and PCNA showed that none of those markers is distinguishable between BCNS-associated and sporadic OKCs, in a 95% confidence interval. The risk of bias was high in 34 studies, moderate in 22, and low in 15.

CONCLUSIONS

The present systematic review and meta-analysis uncovered that, although several immunohistochemical markers might characterize the OKC phenotype, they cannot discriminate between the BCNS-associated and sporadic OKCs.

CLINICAL RELEVANCE

This study highlighted the requirement for additional screening for markers by immunohistochemistry, preferentially coupled to alternative diagnostic applications such as genomics technologies.

Insight into the molecular pathogenesis of odontogenic lesions

BACKGROUND

Odontogenic tumors, derived from epithelial, ectomesenchymal, and/or mesenchymal elements of the tooth-forming apparatus, constitute a heterogeneous group of lesions, including hamartomas, benign and malignant neoplasms with metastatic capabilities.

HIGHLIGHT

This review provides a comprehensive overviewof the pathogenesis of odontogenic tumors and explains the associated molecular events in the context of hallmarks of cancer established by Hanahan D and Weinberg RA. Diagrammatic representations depicted in the article would facilitate easier understanding.

CONCLUSION

A better understanding of the pathogenesis of the lesions may assist in determining patient's prognosis and devising better targeted therapeutic treatment, thus, reducing the morbidity and mortalityof patients.

A systematic review on the expression of bcl-2 in the nonsyndromic odontogenic keratocyst: should it be considered a cyst or a tumor?

The purpose of this study is to find out if the biological behavior and the capacity of the odontogenic keratocyst (OKC) in maintaining pathologic cells alive are more similar to the dentigerous cyst or to the ameloblastoma by assessing bcl-2. We searched MEDLINE, Web of Science, and Scopus for immunohistochemical studies reporting OKCs, dentigerous cysts, and ameloblastomas. Risk difference between the lesions expressing bcl-2 was the effect measure and a P value < 0.05 was considered to provide evidence to the effect estimates. OKCs have an estimated difference of 91% in the probability to express the bcl-2 over dentigerous cysts, but there is no difference in the expression of bcl-2 between OKCs and ameloblastomas. The present study demonstrated a great risk difference in the expression of bcl-2 between OKCs and dentigerous cysts and no risk difference between OKCs and ameloblastomas. OKC's growth may indirectly be attributed to the anti-apoptotic effect of bcl-2 in the cystic epithelium and not only to the increase of its intraluminal pressure. Therefore, the classification of this lesion into keratocystic odontogenic tumor should be carefully reconsidered.

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.

The Role of Dermal Fibroblasts in Nevoid Basal Cell Carcinoma Syndrome Patients: An Overview

Nevoid basal cell carcinoma syndrome (NBCCS), also named Gorlin syndrome, is a rare multisystem genetic disorder characterized by marked predisposition to basal cell carcinomas (BCCs), childhood medulloblastomas, maxillary keratocysts, celebral calcifications, in addition to various skeletal and soft tissue developmental abnormalities. Mutations in the tumor suppressor gene PATCHED1 (PTCH1) have been found to be associated in the majority of NBCCS cases. PATCH1 somatic mutations and loss of heterozygosity are also very frequent in sporadic BCCs. Unlike non-syndromic patients, NBCCS patients develop multiple BCCs in sun-protected skin area starting from early adulthood. Recent studies suggest that dermo/epidermal interaction could be implicated in BCC predisposition. According to this idea, NBCCS fibroblasts, sharing with keratinocytes the same PTCH1 germline mutation and consequent constitutive activation of the Hh pathway, display features of carcinoma-associated fibroblasts (CAF). This phenotypic traits include the overexpression of growth factors, specific microRNAs profile, modification of extracellular matrix and basement membrane composition, increased cytokines and pro-angiogenic factors secretion, and a complex alteration of the Wnt/-catenin pathway. Here, we review studies about the involvement of dermal fibroblasts in BCC predisposition of Gorlin syndrome patients. Further, we matched the emerged NBCCS fibroblast profile to those of CAF to compare the impact of cell autonomous "pre-activated state" due to PTCH1 mutations to those of skin tumor stroma.

Multidisciplinary oral rehabilitation of an adolescent suffering from juvenile Gorlin-Goltz syndrome - a case report

Background

The Gorlin-Goltz syndrome is an autosomal dominant disorder characterized by keratocystic odontogenic tumors in the jaws, multiple basal cell carcinomas and skeletal abnormities. Frequently, the manifestation of the syndrome occurs in the adolescent years.

Case presentation

An 11-year-old boy was referred to our clinic due to the persistence of the lower deciduous molars. The further diagnosis revealed bilateral keratocystic odontogenic tumors in the region of teeth 33 and 45 representing a symptom of a Gorlin-Goltz syndrome. This case of the oral rehabilitation of an adolescent with bilateral keratocystic odontogenic tumors shows the approach of a multidisciplinary treatment concept including the following elements: Enucleation and bone defect augmentation using a prefabricated bone graft; distraction osteogenesis to extend the graft-block vertically after cessation of growth; accompanying orthodontic treatment, guided implant placement and prosthetic rehabilitation. Six months after implant insertion, a new keratocystic odontogenic tumor in the basal part of the left sinus maxillaris had to be removed combined with the closure of the oroantral fistula. During the follow-up period of 18 months in semi-annual intervals, the patient showed no sign of pathology.

Conclusion

In the presented case could be shown that distraction osteogenesis of prefabricated bone blocks is possible. With a multidisciplinary approach in a long-term treatment a sufficient oral rehabilitation of the patient suffering from extended keratocystic odontogenic tumors was possible.

Odontogenic Keratocyst: Developing a Protocol for Surgical Intervention

The aim of this study was to report the outcome of a conservative treatment protocol – “enucleation and packing open” for odontogenic keratocyst (OKC). Ten patients with OKC were treated at our institute by peripheral ostectomy, enucleation followed by open packing. This conservative treatment protocol was selected because of relatively young age of the patients and relatively large size of the lesions. All the cases were monitored at regular predetermined intervals using clinical evaluation and panoramic radiographs. There was no evidence of recurrence during follow-up. The conservative treatment protocol for OKC, based on enucleation followed by open packing would be a possible choice in view of the simplicity of surgical procedure and low morbidity. This treatment modality has a low recurrence rate and may be particularly useful in young patients and patients with advanced systemic disease not amenable to major surgical intervention.

Investigation of clinicopathological parameters and expression of COX-2, bcl-2, PCNA, and p53 in primary and recurrent sporadic odontogenic keratocysts

Objectives

Odontogenic keratocyst (OKC) presents considerable variation in aggressiveness and propensity for recurrence, yet hitherto, no explicit clinicopathological features have been determined to clearly demonstrate the potential for relapse. This retrospective study aims to investigate the prognostic relevance of various clinicopathological features as well as immunoexpression of COX-2, bcl-2, PCNA, and p53 in sporadic OKC.

Materials and methods

Among 41 patients with OKC treated by enucleation, the frequency of recurrence for various clinicopathological features as well as immunoexpression for COX-2, bcl-2, PCNA, and p53 was evaluated.

Results

The mean follow-up was 8.49 years, and recurrences were ascertained in 29.27% of cases. We found significant differences between recurrent and non-recurrent cysts in terms of multilocularity (P = 0.029), cortical perforation (P = 0.001), and lesion size (P < 0.001). Hazard risk for the recurrence was 3.362 (95% CI 1.066–10.598) for multilocular cysts, 7.801 (95% CI 2.1–28.985) for evidence of cortical perforation, and 1.004 (1.002–1.006) for 1 mm² of lesion size on panoramic radiographs. We also found that immunoexpression of PCNA significantly correlates with the radiographic evidence of cortical perforation (P = 0.048) and that there is significant positive correlation between expression of COX-2 and bcl-2 (P = 0.001) as well as significant negative correlation between immunoexpression of COX-2 and age (P = 0.002). None of the other analyzed factors were associated with the recurrence.

Conclusions

Larger size, multilocularity, and cortical perforation in sporadic OKC may be correlated with the relapse.

Clinical relevance

Immunohistochemical analyses of COX-2, bcl-2, PCNA, and p53 lack prognostic utility in sporadic OKC.

Size distribution and clinicoradiological signs of aggressiveness in odontogenic myxoma-three-dimensional analysis and systematic review

OBJECTIVES

Therapeutic assessment of odontogenic myxoma (OM) is poorly standardized. Unidimensional size criteria have shown to be unreliable in therapeutic decision-making. We evaluate the size distribution of OM and scan for associated clinicoradiological signs of aggressiveness. Additionally, we evaluate three-dimensional size delineation of OM aiming to improve future therapeutic assessment of this destructive neoplasm.

METHODS

Primarily, we reviewed the database "PubMed" for data concerning the size of OMs as radiologically determined. Afterwards, the impact of age, sex, locularity and location on the size was investigated by χ² test, Student's t-test and regression analysis. Furthermore, we statistically evaluated the impact of size on the occurrence of clinicoradiological signs of aggressiveness. Secondly, we approximated the volume of five unpublished cases of OM by semi-automatic image segmentation of cone-beam CT images.

RESULTS

Multilocular OMs were significantly larger than unilocular ones (p < 0.002). Age (0.042) and multilocularity (<0.002) significantly impacted size. Size was significantly associated with cortical perforation (0.032) and multilocularity (<0.002), further regression analysis revealed tooth resorption (0.019), cortical perforation (0.005) and multilocularity (<0.002) as significant predictors of size. Employing the volume as a mean of comparison, we found that the biggest OM (38.42 ml; multilocular) was 124 times larger than the smallest (0.31 ml; unilocular). However, using the maximum diameter (cm) as a surrogate for size, the biggest lesion (6.3) was only 5.25 times larger than the smallest (1.2).

CONCLUSIONS

Locularity and volumetric size characterization might help in therapeutic decision-making and could help to improve our understanding of OM.

The Clinical Features and Expression of bcl-2, Cyclin D1, p53, and Proliferating Cell Nuclear Antigen in Syndromic and Nonsyndromic Keratocystic Odontogenic Tumor

The aim of this study was to describe the clinical features and expression of bcl-2, cyclin D1, p53, and proliferating cell nuclear antigen (PCNA) antibodies in syndromic (nevoid basal cell carcinoma syndrome [NBCCS]) and nonsyndromic patients diagnosed with keratocystic odontogenic tumor (KCOT).

METHODS

This descriptive study comprised 5 patients of KCOT associated with NBCCS and 8 patients of nonsyndromic type treated in the Department of Oral Maxillofacial Surgery, Universiti Kebangsaan Malaysia Medical Centre between years 1998 and 2011. The clinical features (site, size, treatment, and recurrence), demographic characteristics, and immunohistochemistry results using antibodies of bcl-2, cyclin D1, p53, and PCNA were examined. The association of the antibody expression and the type of KCOT was analyzed using Fisher exact test.

RESULTS

Altogether there were 13 patients, 5 with syndromic KCOT (1 patient met 3 major criteria of NBCCS) and 8 with sporadic KCOT. The age range for syndromic KCT was 11 to 21 years (mean 16.00 years, SD 4.36) and 10 to 54 years (median 24.50 years, interquartile range 19.00) for the nonsyndromic KCOT. Tumor recurrence occurred in 3 patients (7.7%); 1 patient from the syndromic and 2 patients from the nonsyndromic. The most positive expression was observed in PCNA for both the syndromic and nonsyndromic samples and the least positive expression involved the p53.

CONCLUSION

PCNA, bcl-2 protein, and cyclin D1 expressions could be useful in evaluating the proliferative activity of the tumor and the aggressiveness of the clinical presentation; however, the authors would propose for larger sample size research for more definitive results.

Use of anteromedial thigh perforator flap and immunological implications of Gorlin-Goltz syndrome: a case study

Gorlin-Goltz syndrome is mainly characterised by the development of numerous multicentric and relapsing cutaneous basal cell carcinomas (BCCs). A major problem for patients with Gorlin-Goltz syndrome is the large amount of BCCs that can invade the deep underlying structures, especially the face. Here, we describe the case of a 23-year-old male affected by Gorlin-Goltz syndrome. He had recurrent BCCs on a hairless scalp and dorsum since he was 17 years old and underwent four surgical procedures to excise BCCs, including a reconstruction with anteromedial thigh perforator flap. For each of the surgical procedures, a phenotypic study on peripheral blood mononuclear cells using flow cytometry was performed on the same day of surgery, and on days 7, 14 and 21 after surgery. The role of the tumour-specific cytolytic immune response as a potential future treatment of syndromic BCCs and its trend in relation to surgical ablation of large portions of tumour tissue was examined, and the cosmetic and therapeutic results are shown.

Gorlin-Goltz Syndrome: Case report and literature review

Gorlin-Goltz syndrome (GGS) is an infrequent multisystemic disease with an autosomal dominant trait, with complete penetrance and variable expressivity, though sporadic cases have been described. This article includes a case report and an extensive review of the GGS with regard to its history, incidence, etiology, features, investigations, diagnostic criteria, keratocystic odontogenic tumor and treatment modalities.

Expression of Bcl-2 and epithelial growth factor receptor proteins in keratocystic odontogenic tumor in comparison with dentigerous cyst and ameloblastoma

Background:

Keratocystic odontogenic tumor (KCOT) is a developmental odontogenic cyst on which various investigations have been focused due to its biological activities, high tendency to recur and different growth mechanisms in comparison with other cystic lesions. Previous studies have shown different biological and proliferative activities for the lining epithelium of KCOT. The aim of this study was immunohistochemical evaluation of Bcl-2 and epidermal growth factor receptor (EGFR) expression in KCOT compared with dentigerous cyst and ameloblastoma.

Materials and Methods:

Formalin-fixed and paraffin-embedded tissue sections of 16 cases of KCOT, 16 cases of dentigerous cyst and 16 cases of ameloblastoma were immunohistochemically analyzed to determine Bcl-2 and EGFR proteins’ expression. Biotin-Stereotavidin method was used. It was observed by two oral pathologists separately, and the data were analyzed by Mann–Whitney and Kruskul–Wallis. P < 0.05 was considered as significant.

Results:

Regardless of staining intensity, all cases of ameloblastoma and KCOT except dentigerous cases were positively stained for Bcl-2. Expression of Bcl-2 was higher in the peripheral layer of ameloblastoma and basal layer of KCOT. Furthermore, all cases of ameloblastoma and dentigerous cysts except KCOT samples were positively stained for EGFR. Expression of EGFR was higher in the peripheral layer of ameloblastoma and basal layer of dentigerous cysts.

Conclusion:

According to the expression of — Bcl-2 in ameloblastoma and KCOT, and no expression of EGFR in KCOT, it can be concluded that the biological activity and growth mechanisms of KCOT are different compared with other cystic lesions. However, the aggressive potential of KCOT is not as severe as that of a neoplasm such as ameloblastoma.

Metallothionein immunoexpression in non-syndromic and syndromic keratocystic odontogenic tumour

Background

To compare the metallothionein (MT) immunoexpression in non-syndromic and syndromic keratocystic odontogenic tumour (KOT), to correlate MT with cellular proliferation, and to evaluate the influence of inflammation in MT.

Material and Methods

Fourteen cases of KOT were submitted to immunohistochemistry for MT and Ki-67 analysis. The lesions were grouped according to their grade of inflammation, and statistical analysis was performed.

Results

MT was higher in non-syndromic KOT than in syndromic KOT (p<0.05). No statistical difference in Ki-67 could be identified; however, an inverse correlation was observed between MT and Ki-67 in both lesions. When analysing inflammation, non-syndromic KOT showed no differences in either MT or Ki-67.

Conclusions

The MT immunophenotype of syndromic KOT was different from non-syndromic KOT. MT might not be involved in the proliferation control of both KOT. MT and Ki-67 immunoexpressions proved to be unaffected by inflammation in non-syndromic KOT.

Key words: Odontogenic tumours, basal cell nevus syndrome, metallothionein, Ki-67 Antigen, immunohistoche-mistry.

NCAM (CD56) expression in keratin-producing odontogenic cysts: aberrant expression in KCOT

Objective

To investigate immunohistochemically the expression of neural cell adhesion molecule (NCAM), which has been identified as a signaling receptor with frequent reactivity in ameloblastomas (AB), in a series of keratin-producing odontogenic cysts (KPOCs).

Material and methods

Immunohistochemical expression of NCAM, using a monoclonal antibody, was determined in a series of 58 KPOCs comprising 12 orthokeratinized odontogenic cysts (OOCs) and 46 keratocystic odontogenic tumors (KCOTs), corresponding to 40 non-syndromic KCOT (NS-KCOTs) and 6 syndromic KCOT (S-KCOTs), associated with nevic basocellular syndrome (NBCS).

Results

NCAM expression was negative in all OOCs, but 36.45% of KCOTs exhibited focal and heterogeneous expression at the basal cell level, as well as in basal budding areas and the basal cells of daughter cysts. The latter two locations were especially applicable to S-KCOTs, with focal NCAM reactivity occurring in 66.66% of cases.

Conclusions

Aberrant NCAM expression, in KCOTs but especially in S-KCOTs, together with its immunomorphological location, suggests that this adhesion molecule and signaling receptor plays a role in the pathogenesis of KCOTs, with a probable impact on lesional recurrence.

Electronic supplementary material

The online version of this article (doi:10.1186/s13005-015-0060-2) contains supplementary material, which is available to authorized users.

Differential expression of cyclin D1 in keratin-producing odontogenic cysts

Objetives: The aim of the present study was to analyze the expression levels of Cyclin D1 (CCD1), a nuclear protein that plays a crucial role in cell cycle progression, in a series of keratin-producing odontogenic cysts. Study Design: A total of 58 keratin-producing odontogenic cysts, diagnosed over ten years and classified according to the WHO 2005 criteria, were immunohistochemically analyzed in terms of CCD1 expression, which was quantified in the basal, suprabasal and intermediate/superficial epithelial compartments. The extent of immunostaining was measured as a proportion of total epithelial thickness. Quantified immunohistochemical data were correlated with clinicopathological features and clinical recurrence. Results: Keratin-producing odontogenic cysts were classified as 6 syndromic keratocystic odontogenic tumors (S-KCOT), 40 sporadic or non-syndromic KCOT (NS-KCOT) and 12 orthokeratinized odontogenic cysts (OOC). Immunohistochemically, CCD1 staining was evident predominantly in the parabasal region of all cystic lesions, but among-lesion differences were apparent, showing a clear expansion of parabasal compartment especially in the S-KCOT, followed to a lesser extent in the NS-KCOT, and being much more reduced in the OOC, which had the greatest average epithelial thickness. Conclusions: The differential expression of CCD1 noted in the present study suggests that dysregulation of cell cycle progression from G1 to the S phase contributes to the different aggressiveness of these lesions. However, CCD1 expression levels did not predict NS-KCOT recurrence, which is likely influenced by factors unrelated to lesion biology.

Key words:Keratin-producing odontogenic cyst, keratocyst, keratocystic odontogenic tumor, nevoid basal cell carcinoma syndrome, orthokeratinized odontogenic cyst, cyclin D1, immunohistochemistry.

Ki-67 and p53 expression in solitary sporadic, syndrome associated and recurrent keratocystic odontogenic tumor

BACKGROUND

Ki-67 and p53 are markers expressed in actively proliferating cells, particularly in neoplasms.

OBJECTIVES

(1) To study the proliferative potential of epithelia in Solitary Sporadic, Syndrome-associated and Recurrent Keratocystic odontogenic tumors (KCOTs) using Ki67 and p53 labeling indices (LI). (2) To derive a relationship if any between the expression of these proteins and the biologic behavior of Solitary Sporadic and Syndrome associated KCOTs.

STUDY DESIGN

Thirteen paraffin embedded blocks of KCOTs (Solitary Sporadic, n = 03; Recurrent, n = 03; Syndrome associated, n = 07) were stained immunohistochemically for Ki-67 and p53 and labeling indices were calculated.

STATISTICAL ANALYSIS

Z test with predetermined alpha set at 0.05 was used for the comparison of Ki-67 positivity between the three groups and p53 positivity between the three groups.

RESULTS

Ki-67 labeling indices were: 30% in solitary sporadic; 26% in recurrent; and 32% in syndrome associated KCOTs. p53 labeling indices were: 19% in solitary sporadic; 23% in recurrent; and 21% in syndrome-associated KCOTs. There was no difference seen in the rate of proliferation in the epithelial linings between the three groups. However, in our cases where Ki-67 positivity was seen there was expression of p53. Though not statistically significant a trend was seen, reflecting the loss of balance between the proliferative potential and apoptotic activity.

CONCLUSION

On the basis of proliferative index alone it is not possible to comment on biological behavior of KCOTs associated with syndrome versus those of solitary and recurrent. There is probably a mesenchymal role which needs to be researched.

Proteomics profiling of keratocystic odontogenic tumours reveals AIDA as novel biomarker candidate

BACKGROUND

Keratocystic odontogenic tumour (KCOT) is a benign, yet aggressive odontogenic tumour. Herein, proteome analysis of KCOT lesions in comparison with control patient-matched tissue unaffected by the disease and with inflammatory odontogenic cysts, namely radicular cysts is presented.

METHODS

For the proteomics profiling, two complementary proteomics techniques MALDI-MS/MS and LC-ESI-MS/MS were employed. Potential candidate biomarkers were validated by immunohistochemistry.

RESULTS

More than 43 proteins were found to be differentially expressed or up-regulated in KCOT lesions in comparison with patient-matched unaffected oral mucosa. These proteins bear important biological functions and are involved in cell proliferation, cytoskeletal re-organization, transcription, cellular motility and apoptosis. In particular, a number of differentially expressed proteins participate in autocrine regulation and signalization within JNK and p38 MAPK signalling pathways.

CONCLUSIONS

Immunohistochemical validation of chosen putative biomarkers revealed axin interaction partner and dorsalization-antagonist (AIDA), known as a protein that blocks activation of JNK signalling pathway, as a differential biomarker for KCOT lesions on an independent cohort of KCOT tissue samples in comparison with most prevalent intra-oseal lesions inflammatory odontogenic cysts.

Increased expression of autophagy-related proteins in keratocystic odontogenic tumours: its possible association with growth potential

The aim of this study was to evaluate the activation status of autophagy in keratocystic odontogenic tumours (KCOT), and to investigate its possible association with growth potential. We detected the expression of some key autophagy-related proteins in clinical samples of KCOT and radicular cysts and compared then by real-time quantitative polymerase chain reaction (qPCR) and immunohistochemical analysis, respectively. The correlation between the autophagy-related proteins tested, and with cell antiapoptotic (Bcl-2) or proliferative (Ki-67) markers in KCOT was explored using Spearman's rank correlation, followed by cluster analysis. The results showed that both the expression of mRNA and the immunoreactivity of the autophagy-related proteins tested were considerably increased in samples of KCOT compared with those in samples of radicular cysts. The correlation analyses showed that the immunostains of autophagy-related proteins in samples of KCOT correlated closely with each other. The immunostains of these autophagy-related proteins also correlated closely with the immunostains of Bcl-2 and Ki-67 in KCOT. More importantly, double-labelling immunofluorescence analyses also showed that the distribution of autophagic and proliferative markers was partially synchronous in samples from KCOT. We have, to our knowledge for the first time, implicated the activation of autophagy in KCOT, and showed its possible association with growth potential.

Odontogenic keratocyst: What is in the name?

The classification of odontogenic cysts is complicated and can create confusion for both clinicians and pathologists. The odontogenic keratocyst (OKC) is an enigmatic developmental cyst that deserves special attention. It has characteristic histopathological and clinical features; but, what makes this cyst special is its aggressive behavior and high recurrence rate. Despite of many classifications and nomenclature, unfortunately the clinicians still have to face difficulties in the management of this commonly found jaw lesion. This article is an effort to provide an overview of various aspects of OKC with emphasis on nomenclature, recurrence, molecular aspects, and management of OKC.

PTCH1 gene mutations in Keratocystic odontogenic tumors: a study of 43 Chinese patients and a systematic review

BACKGROUND

The keratocystic odontogenic tumor (KCOT) is a locally aggressive cystic jaw lesion that occurs sporadically or in association with nevoid basal cell carcinoma syndrome (NBCCS). PTCH1, the gene responsible for NBCCS, may play an important role in sporadic KCOTs. In this study, we analyzed and compared the distribution pattern of PTCH1 mutations in patients with sporadic and NBCCS-associated KCOTs.

METHODS

We detected PTCH1 mutations in 14 patients with NBCCS-associated KCOTs and 29 patients with sporadic KCOTs by direct sequencing. In addition, five electronic databases were searched for studies detecting PTCH1 mutations in individuals with NBCCS-associated or sporadic KCOTs, published between January 1996 and June 2013 in English language.

RESULTS

We identified 15 mutations in 11 cases with NBCCS-associated KCOTs and 19 mutations in 13 cases with sporadic KCOTs. In addition, a total of 204 PTCH1 mutations (187 mutations from 210 cases with NBCCS-associated and 17 mutations from 57 cases with sporadic KCOTs) were compiled from 78 published papers.

CONCLUSIONS

Our study indicates that mutations in transmembrane 2 (TM2) are closely related to the development of sporadic KCOTs. Moreover, for the early diagnosis of NBCCS, a genetic analysis of the PTCH1 gene should be included in the new diagnostic criteria.

Expression of cell cycle and apoptosis-related proteins in ameloblastoma and keratocystic odontogenic tumor

Tumors arising from epithelium of the odontogenic apparatus or from its derivatives or remnants exhibit considerable histologic variation and are classified into several benign and malignant entities. A high proliferative activity of the odontogenic epithelium in ameloblastoma (AM) and keratocystic odontogenic tumor (KCOT) has been demonstrated in some studies individually. However, very few previous studies have simultaneously evaluated cell proliferation and apoptotic indexes in AM and KCOT, comparing both lesions. The aim of this study was to assess and compare cell proliferation and apoptotic rates between these two tumors. Specimens of 15 solid AM and 15 KCOT were evaluated. The proliferation index (PI) was assessed by immunohistochemical detection of Ki-67 and the apoptotic index (AI) by methyl green-pyronin stain. KCOT presented a higher PI than AM (P < .05). No statistically significant difference was found in the AI between AM and KCOT. PI and AI were higher in the peripheral cells of AM and respectively in the suprabasal and superficial layers of KCOT. In conclusion, KCOT showed a higher cell proliferation than AM and the AI was similar between these tumors. These findings reinforce the classification of KCOT as an odontogenic tumor and should contribute to its aggressive clinical behavior.

Cell proliferation and apoptosis in ameloblastomas and keratocystic odontogenic tumors

A high proliferative activity of the odontogenic epithelium in ameloblastoma (AM) and keratocystic odontogenic tumor (KOT) has been demonstrated. However, no previous study has simultaneously evaluated cell proliferation and apoptotic indexes in AM and KOT, comparing both lesions. The aim of this study was to assess and compare cell proliferation and apoptotic rates between these two tumors. Specimens of 11 solid AM and 11 sporadic KOT were evaluated. The proliferation index (PI) was assessed by immunohistochemical detection of Ki-67 and the apoptotic index (AI) by methyl green-pyronine and in situ DNA nick end-labelling methods. KOT presented a higher PI than AM (p<0.05). No statistically significant difference was found in the AI between AM and KOT. PI and AI were higher in the peripheral cells of AM and respectively in the suprabasal and superficial layers of KOT. In conclusion, KOT showed a higher cell proliferation than AM and the AI was similar between these tumors. These findings reinforce the classification of KOT as an odontogenic tumor and should contribute to its aggressive clinical behavior.

Immunohistochemical expression of cyclin D1 in ameloblastomas and adenomatoid odontogenic tumors

BACKGROUND

Cyclin D1, a member of G1 cyclins, controls the cell-cycle transit from the G1 to S phase. The deregulation and overexpression of cyclin D1 has been revealed in many tumors of diverse histogenesis. Ameloblastoma is the most frequently encountered odontogenic tumor known for its local invasiveness and a high tendency to recur. The adenomatoid odontogenic tumor is a benign, nonaggressive tumor with a limited growth and no tendency to recur.

AIM

The aim was to investigate whether the immunohistochemical expression of cyclin D1 as a proliferation marker in ameloblastoma and adenomatoid odontogenic tumor correlates with the known clinical behavior of these two benign neoplasms.

MATERIALS AND METHODS

Ameloblastoma cases consisted of follicular, plexiform, and unicystic subtypes. The positive staining was assessed based on intensity of staining, localization of staining, and in different cell types in both the tumors. Two cases of follicular ameloblastoma and one case of plexiform ameloblastoma showed intense staining, but the predominant staining intensity was overall mild in both ameloblastoma and adenomatoid odontogenic tumors. The immunoreactivity was found both in nucleus and cytoplasm in ameloblastoma and only nuclear in adenomatoid odontogenic tumors. The peripheral columnar and central stellate reticulum-like cells of ameloblastoma showed immunoreactivity with squamous and granular cells being negative. In adenomatoid odontogenic tumors, the whorls showed predominant localization of staining. Statistical comparison with a Mann-Whitney U-test showed no significant difference in staining intensities between different histologic subtypes of ameloblastomas and also between ameloblastoma and adenomatoid odontogenic tumors (P>0.005).

CONCLUSION

The marked expression of cyclin D1 in these tumors suggested its participation in proliferation of both the tumors and its expression patterns were irrespective of their known biologic behavior.

Novel PTCH1 mutations in patients with keratocystic odontogenic tumors screened for nevoid basal cell carcinoma (NBCC) syndrome

Keratocystic odontogenic tumors (KCOTs) are cystic tumors that arise sporadically or associated with nevoid basal cell carcinoma syndrome (NBCCS). NBCCS is a rare autosomal dominantly inherited disease mainly characterized by multiple basal cell carcinomas, KCOTs of the jaws and a variety of other tumors. PTCH1 mutation can be found both in sporadic or NBCCS associated KCOTs. The aim of the current study was to assess whether a combined clinical and bio-molecular approach could be suitable for the detection of NBCCS among patients with a diagnosis of keratocystic odontogenic tumors (KCOTs). The authors collected keratocystic odontogenic tumors recorded in the database of the Pathology Department of the University of Modena and Reggio Emilia during the period 1991–2011. Through interviews and examinations, family pedigrees were drawn for all patients affected by these odontogenic lesions. We found out that 18 of the 70 patients with KCOTs and/or multiple basal cell carcinomas actually met the clinical criteria for the diagnosis of NBCCS. A wide inter- and intra-familial phenotypic variability was evident in the families. Ameloblastomas (AMLs) were reported in two probands that are also carriers of the PCTH1 germline mutations. Nine germline mutations in the PTCH1 gene, 5 of them novel, were evident in 14 tested probands. The clinical evaluation of the keratocystic odontogenic tumors can be used as screening for the detection of families at risk of NBCCS. Keratocystic odontogenic lesions are uncommon, and their discovery deserves the search for associated cutaneous basal cell carcinomas and other benign and malignant tumors related to NBCCS.

Survivin gene promoter polymorphism -31G/C as a risk factor for keratocystic odontogenic tumor development

Several single nucleotide polymorphisms in survivin gene promoters, notably -31G/C, have been shown to modulate the expression and activity of the survivin protein. Consequently, the -31G/C polymorphism has been identified as a risk factor for the development of several types of tumors. The aim of this study was to investigate a possible association between the -31G/C polymorphism and the risk for keratocystic odontogenic tumor (KCOT) development. DNA from 52 biopsy specimens of KCOTs and from 82 buccal swabs of healthy individuals was subjected to PCR restriction fragment length polymorphism analysis to identify individual genotypes. The distribution of genotypes in KCOT and control groups, respectively, was: GG: 30 (57.7%) vs. 26 (31.7%); CG: 17 (32.7%) vs. 45 (54.9%); and CC: 5 (9.6%) vs. 11 (13.4%), respectively. These differences were statistically significant. The G allele was more common in the KCOT group than in the control group: 76 (74%) vs. 96 (59%), respectively. Logistic regression analysis showed that GC heterozygotes had a considerably decreased susceptibility for KCOTs compared with GG homozygotes. The same was true for GC+CC vs. GG. The GG genotype of the -31G/C polymorphism might be a risk factor for KCOT development.

Odontogenic keratocysts/keratocystic odontogenic tumours: biological characteristics, clinical manifestation and treatment

BACKGROUND

Odontogenic keratocysts (OKCs) now reclassified as Keratocystic odontogenic tumours (KCOTs) are a clinical entity with a characteristic microscopic picture, kinetic growth and biological behaviour. They arise from the proliferation of the epithelial dental lamina in both maxilla and mandible and occur in patients of all ages. 70-80% of keratocysts are found in the mandible commonly in the angle between the jaw and mandibular branch and maxillary region of the third molar. The cysts are long latent, often symptomless and may attain remarkable dimensions without significant deformation of the jaw bones. They are often found during routine dental X-ray examination. Compared to other types of jaw cyst, odontogenic cysts have a striking tendency to rapid growth and re-occurrence.

AIMS

This review focuses on the biological characteristics, clinical behaviour and treatment of KCOTs.

METHODS

The databases searched were the PubMed interface of MEDLINE and LILACS.

RESULTS AND CONCLUSIONS

Ondontogenic keratinocysts are not currently a diagnostic problem. Orthopantomograms which are today ordinary tools of dental investigation enable diagnosis of clinically asymptomatic cystic lesions. The problem remains the optimal therapeutic approach to reduce the still high likelihood of postoperative recurrence. There is no complete consensus on the ideal operating procedure but cystectomy with delayed extirpation is favoured. An open question also remains the timeliness of screening for postoperative recurrences. Given that the first clinical manifestation of Nevoid Basal Cell Carcioma Syndome (NBCCS) may be lesions of this type, routine histopathological classification supplemented by analysis of immunophenotype should be done. Patients with proven sporadic and especially syndromic OKC should be long term screened. In patients with NBCC preventive X ray examination is recommended only once a year.

Histopathological Features of Keratocystic Odontogenic Tumor

The aim of this study was to describe the clinicopathologic features of 177 keratocystic odontogenic tumors (KCOTs) diagnosed in a Brazilian population. A total of 177 KCOTs were reviewed and affected 158 patients with ages ranging from 5 to 79 years (mean age = 32 years) with a slight female predominance. Mandible was the most common affected site (69.3%), and a unilocular radiolucency was the most common radiographic image. Microscopically, all cases showed at least focal areas of classic KCOT, but several histological aspects were also observed, including diffuse and focal epithelial lining hyperplasia (48.6%), epithelial budding (12.4%), reactive cytological alterations (11.3%), dystrophic calcification (7.9%), daughter cysts (7.8%), odontogenic epithelial remnants (4.5%), focal areas of orthokeratinization (2.8%), and ameloblastomatous epithelium (1.7%). These variations may make KCOT diagnosis challenging in some cases, so careful full-sample analysis and knowledge of these uncommon histological features associated with KCOT are essential for correct diagnosis.

MMP-13 expression in keratocyst odontogenic tumour associated with NBCCS and sporadic keratocysts

OBJECTIVE

To investigate the matrix metalloproteinase (MMP)-13 expression in associated and non-nevoid basal cell carcinoma syndrome (NBCCS) Odontogenic Keratocysts (OCKs) in order to contribute to a better understanding of the differences in the growth pattern between them.

MATERIALS AND METHODS

Thirty-nine paraffin-embedded blocks of OCKs, 26 sporadic OCKs and 11 NBCCS-associated KCOTs were studied by immunohistochemistry to evaluate MMP-13 expression both in epithelial and stromal layers. A semi-quantitative scale was used to evaluate immunostaining. Obtained data were compared between the two groups, using Fischer's exact test and the chi-square test.

RESULTS

Only 13 of 26 sporadic OCKs showed a positive immunostaining, whilst 11 KCOTs resulted in positive labelling for MMP-13 expression. Moreover, syndromic cysts displayed a more intense and diffuse MMP-13 labelling of the stromal tissue. Instead, in non-syndromic forms, the staining pattern of MMP-13 in stromal tissue was completely absent. Fisher's exact test showed a statistically significant greater prevalence of KCOTs-immunolabelled cysts with respect to sporadic OCKs.

CONCLUSIONS

Results from this study point out that the biological behaviour of these cysts could be related not only to the epithelial layer but also to stromal tissue in that... MMP-13 overexpression in stromal tissue of NBCCS-associated KCOTs could clarify the higher aggressiveness of these cysts.

A comparative immunohistochemical analysis of COX-2, p53, and Ki-67 expression in keratocystic odontogenic tumors

OBJECTIVE

The aim of the present study was to investigate the association between the expression of cyclooxygenase-2 (COX-2) in keratocystic odontogenic tumors (KCOT) and more commonly used markers, such as p53 and Ki-67.

STUDY DESIGN

Expression of cyclooxygenase-2 (COX-2) in 20 biopsy specimens of keratocystic odontogenic tumors (KCOT) has been analyzed and compared with the expression of previously reported markers Ki-67 and p53. Formalin-fixed, paraffin-embedded blocks were sectioned and used for hematoxylin-eosin (H&E) staining and incubated with anti-cox-2, anti-ki-67, and anti-p53 monoclonal antibodies for immunohistochemical examination. Detection of the COX-2 antibody was performed with the EnVision kit. Cellular staining pattern was cytoplasmatic for COX-2 and nuclear for both Ki-67 and p-53. Molecular expressions were semiquantitatively evaluated as negative (-), mild (±) or strong (+).

RESULTS

Mild to strong expression of COX-2 was observed in 20 (100%) of the cases. Fifteen (75%) of the KCOTs stained positive for p53 and 18 (90%) stained positive for Ki-67. There was no statistically relevant difference between the expressions of COX - 2, Ki-67, and p53.

CONCLUSIONS

Although COX-2 has rarely been used to assess the biological activity of the KCOT, the results portrayed in the current study and the current knowledge of the overall role known to be played by COX-2 in tumorigenesis suggest that COX-2 may be an important marker involved in the biological behavior of the KCOT. Larger studies are required to improve our knowledge of the possible role of COX-2 in the pathogenic mechanism involved in KCOT.

Odontogenic epithelium: immunolabeling of Ki-67, EGFR and survivin in pericoronal follicles, dentigerous cysts and keratocystic odontogenic tumors

The aim of this study was to evaluate the biological profile of odontogenic epithelium by immunolabeling of epidermal growth factor receptor (EGFR), Ki-67 and survivin in keratocystic odontogenic tumors (KOT), dentigerous cysts (DC), and pericoronal follicles (PF). Immunohistochemical analysis was performed in 13 KOTs, 14 DCs and 9 PFs. Immunolabeling was analyzed in the basal and suprabasal layers of KOTs and DCs, and in the islands of odontogenic epithelium and/or reduced enamel epithelium of PFs. KOTs showed the highest proliferation rate among the three groups, mainly in suprabasal layers. EGFR immunolabeling was observed mainly in the cytoplasm in basal and suprabasal layers of KOTs and in the suprabasal layer of DCs. Immunolabeling in both membrane and cytoplasm was greater in PFs. In PFs, membrane-only staining was observed. Survivin immunolabeling showed a greater percentage of positive cells (scoring +++) in the suprabasal layer of KOTs. In DCs, both layers showed similar percentages of cells scoring +++; PFs showed the highest percentage of these cells. In KOTs, epithelial cells showed stimulus-independent neoplastic proliferative characteristics, suggesting the presence of a suprabasal proliferative compartment, maintained by inhibition of apoptosis. In DCs, the basal layer seemed to proliferate in response to stimulus. Although PFs showed low proliferative activity, the expression of EGFR indicates that some cells have a high capacity to respond to stimuli, which could probably explain the origin of odontogenic lesions.

[Marsupialization and enucleation of keratocystic odontogenic tumor with the use of Carnoy's solution]

INTRODUCTION

Keratocystic odontogenic tumors (KCOT) or odontogenic keratocysts are aggressive and expansive odontogenic neoplasms with high recurrence rate (25%-60%). There are a small number of publications about the combination of marsupialization and enucleation with the use of Carnoy's solution for the treatment of KCOT.

CASE REPORT

In a female patient, aged 24, marsupialization KCOT was done in the first stage, and enucleation with the use of Carnoy's solution in the second stage, six months later. Lost sensibility of the lower lip was reestablished after three months. A postoperation defect was completely filled in seven months. One year later orthopantomographic x-ray showed the presence of a newly formed bone tissue, whereas in 7 years a completely preserved new mandibular bone and recanalisation of mandibular canal were observed.

CONCLUSION

We consider that our method was successful in the treatment of KCOT, with no occurrence of recidives seven years later. However, it is necessary to follow the patient periodically because of a possible late recidive.