The expression of NF-kappaB, Ki-67 and MMP-9 in CCOT, DGCT and GCOC

Comprehensive clinical, genome and transcriptomic analysis of primary ghost cell odontogenic carcinoma

There is currently no comprehensive genome-wide description of the primary ghost cell odontogenic carcinoma (GCOC), hindering our understanding of pathogenesis. We herein present a case with comprehensive clinical, genome and transcriptomic analysis. These will serve as the first comprehensive molecular atlas for primary GCOC. A 58-year-old male underwent subtotal resection with prosthetic restoration. Genome sequencing (WGS) detected previously identified CTNNB1 mutation with novel alterations of MAP3K, EP300, and 22q11.21 region. Transcriptome results showed significant involvement of cytokine-cytokine receptor interaction and PI3K-Akt signaling pathway. These results need to be compared with more GCOCs for more accurate clinical guidance.

Comparative Analysis Between Dentinogenic Ghost Cell Tumor and Ghost Cell Odontogenic Carcinoma: A Systematic Review

Dentinogenic ghost cell tumor (DGCT) and ghost cell odontogenic carcinoma (GCOC) form a spectrum of rare benign and malignant odontogenic neoplasms, respectively. The aim of this study was to perform a comparative systematic review of the clinicopathological, genetic, therapeutic, and prognostic features of DGCT and GCOC. The electronic search was performed until December 2020 on seven electronic databases. Case reports, series, and research studies with enough histopathological criteria for diagnosis and all genomic studies were included. Both DGCT and GCOC showed a male prevalence (p = 0.043), with mandibular and maxillary predilections, respectively (p = 0.008). Peripheral DGCT (DGCTp) affected most elderly people (p < 0.001), and central DGCT (DGCTc) and GCOC occurred mainly in younger individuals. Unilateral enlargement of maxilla or mandible was the most common clinical sign associated with a radiolucent or mixed image. Ameloblastomatous epithelium was often present in both neoplasms. Basaloid and large cells with vesicular nuclei were also frequently seen in GCOC. β-catenin expression and mutations (CTNNB1 gene) were found in DGCT and GCOC. Conservative surgery was mostly used for DGCTp, while radical resection was chosen for DGCTc and GCOC. High recurrence rates were found in DGCTc and GCOC. Metastasis occurred in 16.7% of GCOC cases and the 5-year survival rate was 72.6%. DGCT and GCOC share numerous clinicopathological features and demand a careful histopathological evaluation, considering the overlap features with other odontogenic tumors and the possibility of malignant transformation of DGCT. A strict regular post-operative follow-up is mandatory due to high recurrence rates and metastatic capacity in GCOC.

Analyses of odontogenic tumours: the most recent classification proposed by the World Health Organization (2017)

BACKGROUND

The fourth edition of the ''WHO Classification of Head and Neck Tumours'' was published in January 2017 and includes a classification of odontogenic tumours. This review aims to examine the changes made in this new classification in comparison with the previous classification of 2005.

MATERIAL AND METHODS

An electronic search was conducted in the PubMed, Scopus and Cochrane databases with the keywords "odontogenic tumor", "WHO classification" and "update". Studies published from January 2009 to April 2019 with a high level of scientific evidence were included, but studies not published in English, epidemiological studies and studies with a low level of evidence were excluded.

RESULTS

The initial search found 457 articles and after eliminating duplicates, 8 studies were selected for full-text assessment. After excluding 3 epidemiological studies, 5 articles were finally included. These studies were stratified by their level of scientific evidence using SORT criteria (Strength of Recommendation Taxonomy).

CONCLUSIONS

The new odontogenic tumour list has been simplified with the objective of improving its role as an international guide for diagnosis. Some changes have been possible thanks to the application of immunohistochemistry and molecular genetic techniques that allow better characterization of certain tumours. Further clinicopathological and molecular studies are needed so that this new classification can be consolidated and/or amended.

Benign odontogenic ghost cell lesions revisited and new considerations on dysplastic dentin

OBJECTIVES

This study aimed to revisit benign odontogenic ghost cell lesions (BOGCL) by hematoxylin and eosin staining and immunohistochemistry.

MATERIALS AND METHODS

Thirty cases of calcifying odontogenic cyst (COC) and 6 cases of dentinogenic ghost cell tumor (DGCT) were selected for histopathological and immunohistochemical analysis. Sections stained for cytokeratin (K) 14, K-19, amelogenin, collagen type 1 (COL-1), and dentin matrix acidic phosphoprotein 1 (DMP-1) were evaluated using qualitative analysis. Sections stained for Ki-67 and minichromosome maintenance protein-2 (MCM-2) were evaluated using semi-quantitative analysis.

RESULTS

A morphologic overlap was noticed in all BOGCL. Moreover, no differences were detected in the expression of K-14 and K-19. The expression of proliferative markers Ki-67 and MCM-2 was similar between cystic and tumor lesions (p > .05). The presence of COL-1 and absence of amelogenin in the so-called dysplastic dentin, associated with its histologic pattern, suggest that this is in fact an enameloid-like tissue.

CONCLUSIONS

The dysplastic dentin should be considered an enameloid-like tissue in these lesions.

CLINICAL RELEVANCE

The similarity in histology, protein expression, and proliferative marker indices between COC and DGCT suggest that they are a sole entity and likely represent types of the same neoplasia.

Matrix metalloprotease-9 expresssion in meningioma: Correlation with growth fraction and role of gender. A pilot immunohistochemical study

OBJECTIVE

Matrix metalloproteases (MMPs), particularly MMP2 and MMP9 increase tumor invasion and edema in meningiomas. Although lesser recognized, MMPs may also enhance cell growth via liberating growth factors or via cleaving inactive growth factors into active isoforms. However, there exist very few studies, which investigated correlation of MMPs with growth fraction in meningiomas. Meningiomas are seen more frequently in women and their growth accelarate during pregnancy. However, no study examined whether MMP-expressions in meningioma differ with gender.

PATIENTS AND METHODS

In a pilot immunohistochemical study, we analyzed the correlation of MMP9 expression with Ki67 index and whether gender influences MMP9 expression. We retrospectively selected 24 meningioma cases including 10 cases with WHO Grade-1 tumors and 7 cases each with WHO Grade-2 and 3 tumors, respectively.

RESULTS

We separately determined the intensity and area of MMP9 staining and also calculated an expression index by multiplying these two parameters. Spearman correlation analyses revealed that MMP9 staining intensity, staining area and expression index significantly correlated with Ki67 proliferation index. MMP9 staining indices were significantly higher in women specimens.

CONCLUSION

If these findings will be confirmed in larger series, MMP-inhibitors and female hormone receptor-antagonists may be combined to augment chemotherapy efficacy and to attenuate invasion in high-grade meningiomas.

Potential involvement of chondroitin sulfate A in the pathogenesis of ameloblastoma

Ameloblastoma is classified as a benign odontogenic tumor characterized by locally invasive behavior and high risk of recurrence. Here, we evaluate a potential role for glycosaminoglycan, a structural component of cell membranes and extracellular matrix, in ameloblstoma pathogenesis. We subjected formalin-fixed, paraffin-embedded tissue sections of 34 cases of ameloblastoma, 10 of odontogenic keratocyst, and 17 of dentigerous cyst to immunohistochemistry using monoclonal antibodies recognizing chondroitin sulfate A (CS-A), heparan sulfate (HS), and keratan sulfate (KS). Expression levels of CS-A in epithelial component and stroma of ameloblastoma were significantly higher than those in odontogenic keratocyst and dentigerous cyst. Moreover, CS-A in ameloblastoma was more strongly expressed in stellate reticulum-like cells than in amelobast-like cells with statistical significance. On the other hand, expression levels of HS and KS in epithelial component and stroma of ameloblastoma were lower compared with CS-A. These results overall reveal that among these odontogenic lesions, CS-A is preferentially expessed in ameloblastoma, suggesting potential pathogenetic role probably in cytodifferention of tumor cells to stellate reticulum-like cells.

Kallikrein 4 and matrix metalloproteinase-20 immunoexpression in malignant, benign and infiltrative odontogenic tumors

CONTEXT

Matrix metalloproteinase-20 (MMP20) (enamelysin) and kallikrein 4 (KLK4) are enzymes secreted by ameloblasts that play an important role in enamel matrix degradation during amelogenesis. However, studies have shown that neoplastic cells can produce such enzymes, which may affect the tumor infiltrative and metastatic behaviors.

AIMS

The aim of this study is to assess the biological role of MMP20 and KLK4 in odontogenic tumors.

MATERIALS AND METHODS

The enzymes were analyzed immunohistochemically in ameloblastoma, adenomatoid odontogenic tumor (AOT), calcifying epithelial odontogenic tumor, keratocystic odontogenic tumor with or without recurrence and odontogenic carcinoma.

STATISTICAL ANALYSIS USED

Clinicopathological parameters were statistically correlated with protein expression using the Fisher's exact test. Kruskal-Wallis and Wilcoxon-independent methods were used to evaluate the differences in median values.

RESULTS

Positive Immunoexpression was detected in all benign lesions, with a prevalence of 75-100% immunolabeled cells. Patients were predominantly young, Caucasian, female, with slow-growing tumors located in the mandible causing asymptomatic swelling. No KLK4 expression was seen in carcinomas, and the amount of MMP20-positive cells varied between 20% and 80%. Rapid evolution, recurrence and age >60 years characterized the malignant nature of these lesions.

CONCLUSIONS

Data showed that KLK4 and MMP20 enzymes may not be crucial to tumoral infiltrative capacity, especially in malignant tumors, considering the diversity and peculiarity of these lesions. The significant immunoexpression in benign lesions, remarkably in AOT, is likely associated with differentiated tumor cells that can produce and degrade enamel matrix-like substances. This would be expected since the histogenesis of odontogenic tumors commonly comes from epithelium that recently performed a secretory activity in tooth formation.

Malignant transformation of calcifying cystic odontogenic tumour - a review of literature

Calcifying cystic odontogenic tumour (CCOT) has been classified as an odontogenic tumour. Ghost cell odontogenic carcinoma (GCOC) is the malignant counterpart of CCOT. This paper aims to review the literature regarding malignant transformation of CCOT. A literature search was done via the National Library of Medicine PubMed interface, searching for articles relating to malignant transformation of CCOT. From these articles, references were obtained, and from their references lists, pertinent secondary references were also identified and acquired. After reviewing the literature, we found 26 cases of GCOC which developed from CCOT. Malignant transformation of CCOT was seen more commonly in the maxilla. Histologically, changes such as increased nuclear/cytoplasmic ratio, atypical mitotic figures have been reported after malignant transformation. Immunohistochemical analysis has shown an increased expression of ki-67 and p53 in tumour cells. Malignant transformation of CCOT, although rare, mostly takes place in recurrent and long standing cases.

A discussion of some advancements and some persistent difficulties in the recognition and understanding of the histopathologic and molecular features of selected odontogenic tumors and tumor-like malformations

Overgrowths of epithelial, ectomesenchymal, and/or mesenchymal elements of the tooth-forming apparatus are quite variable with respect to their histopathologic characteristics and biological behaviors. Investigations of a variety of odontogenic lesions have led to an enhanced comprehension of many salient diagnostic features. This discussion provides an update with respect to the understanding of odontogenic tumors and tumor-like malformations and attempts to assist pathologists in the recognition and classification of these lesions.

Ghost cell odontogenic carcinoma: A rare case report and review of literature

Objectives: Ghost cell odontogenic carcinoma is a rare condition characterized by ameloblastic-like islands of epithelial cells with aberrant keratinitation in the form of Ghost cell with varying amounts of dysplastic dentina. Material and Methods: We report a case of a 70 year-old woman with a rapid onset of painful swelling right maxillary tumor. Magnetic resonance showed a huge tumor dependent on the right half of the right hard palate with invasion of the pterygoid process and focally to the second branch of the trigeminal. Radiological stage was T4N0. The patient underwent a right subtotal maxillectomy with clear margins. Adjuvant radiotherapy was given. The patient was free of residual or recurrent disease 12 months after surgery. Results: The tumor was 3,9cm in diameter. It was spongy and whitish gray. Microscopically the tumor was arranged in nets and trabeculae, occasionally forming palisade. Tumoral cells had clear cytoplasm with vesicular nuclei. There was atipia and mitosi with vascular and perineural invasion. The excised tumor was diagnosed as a GCOC. Conclusions: Ghost cell carcinoma is a rare odontogenic carcinoma. Its course is unpredictable, ranging from locally invasive tumors of slow growth to highly aggressive and infiltrative ones. Wide surgical excision with clean margins is the treatment of choice although its combination with postoperative radiation therapy, with or without chemotherapy, remains controversial.

Key words:Ameloblastic carcinoma, calcifying odontogenic cyst, Ghost cell carcinoma, keratinizing epithelial odontogenic cyst, maxillary tumor, odontogenic carcinoma.

Malignant odontogenic tumors: an update on selected tumors

This is an update on selected odontogenic malignancies. The article deals with aspects of recognized odontogenic carcinomas, odontogenic sarcoma and a yet unrecognized entity, sclerosing odontogenic carcinoma. Odontogenic malignancies are exceedingly rare, complicating a thorough understanding of the biologic behavior, reproducible standardized diagnostic criteria, appropriate classification and clinical management. Without the knowledge of the tumor's biologic behavior, adequate clinical management is difficult and patient outcomes uncertain. The histopathologic features are emphasized as well as the more recent biomarker findings. These recent advances may facilitate further understanding of this group of malignancies and provide useful stratification to guide patient management.

Immunoexpression of NF-ĸB and their inhibitory subunits IĸBα and IĸBβ in giant cell lesions of the jaws: implications for their clinical behavior

BACKGROUND

The unpredictable behavior of giant cell lesions (GCLs) of the jaws parallels its controversial histogenesis. This study evaluated a possible association between the immunohistochemical expression of NF-ĸB, the inhibitory subunits IĸBα/IĸBβ, and clinicopathological variables with the behavior of central and peripheral GCLs of the jaws.

MATERIALS AND METHODS

Paraffin-embedded samples of GCLs of the jaws (n = 68) were prepared for histological/immunohistochemical assessment. Demographic and clinicopathological parameters were assessed to determine the behavior of the lesions. A staining-intensity-distribution (SID) score was used to assess the immunomarkers reactivity. The association between significant candidate immunohistochemical predictor variables regarding clinical behavior was analyzed individually and adjusted for confounding using a binary logistic regression model.

RESULTS

While univariate analysis revealed a positive association of NF-ĸB SID score, NF-ĸB nuclear expression, IĸBα SID score, and NF-ĸB to inhibitors average ratio with the aggressive status of GCLs, after bivariate logistic regression analysis, only NF-ĸB nuclear expression, IĸBα SID score, and NF-ĸB to inhibitors average ratio remained as robust predictors of aggressiveness. Confounding and interaction effects regarding clinicopathological candidate predictor variables were also noted.

CONCLUSION

It looks that clinical behavior of GCLs of the jaws may be strong/independently linked to the increased nuclear expression of NF-ĸB, higher NF-ĸB to inhibitors average ratio, and decreased IĸBα SID score. Notwithstanding, there are simultaneously synergistic and opposing interactive effects with respect to age stratum, growth rate, multinucleated giant cells count, and mononuclear stromal cells density in the susceptible host that may increase the tissue destruction observed in aggressive GCLs.

The diagnostic usefulness of immunohistochemistry for odontogenic lesions

The diagnosis of odontogenic tumors can be challenging, largely due to their rarity and consequent difficulties in gaining experience in their assessment. In most cases, careful attention to morphology, in conjunction with clinical and radiological features will allow a diagnosis to be made. However, in some cases, immunohistochemical analysis of the tumor may be useful. In this review we will outline the immunohistochemical expression profile of normal developing odontogenic tissues and a range of odontogenic tumors. In many cases the immunohistochemical markers are neither specific nor sensitive enough to be of help in diagnosis, but in some cases such analysis may prove very useful. Thus we have outlined a limited number of circumstances where immunohistochemistry may be of use to the practicing diagnostic pathologist.

RANK, RANKL, and OPG in recurrent solid/multicystic ameloblastoma: their distribution patterns and biologic significance

OBJECTIVES

To determine the distribution patterns of bone resorption regulators, receptor activator of nuclear factor κ-B (RANK), RANK ligand (RANKL), and osteoprotegerin (OPG) in recurrent ameloblastoma (RAs) and to clarify their impact on the biologic behavior of these neoplasms.

MATERIALS AND METHODS

Fifteen paraffin-embedded RA cases were subjected to immunohistochemistry for expression of RANK, RANKL, and OPG.

RESULTS

The RANK-RANKL-OPG triad was heterogeneously detected in RA samples. RANK, essential for osteoclast differentiation, was strongly expressed in tumoral epithelium. Conversely, RANKL, an osteoclast activator, was markedly underexpressed, and protein localization was predominantly stromal. OPG, an osteoclastogenesis inhibitory factor, was detected in neoplastic epithelium more than in stroma, suggesting functional inactivation of RANKL. Most RA (n = 12/15; 80%) exhibited a bimolecular spatial expression pattern, the most common being RANK-positive/OPG-positive (n = 8/15; 53.3%). All three proteins showed no significant correlation with the clinical/histopathologic parameters in RA patients (P > .05).

CONCLUSIONS

The RANK(+)/RANKL(low/-)/OPG(+) phenotype observed in RA suggests an altered local bone metabolism characterized by low bone resorptive activity in these recurrent tumors.

Calcifying Cystic Odontogenic Tumour: immunohistochemical expression of matrix metalloproteinases, their inhibitors (TIMPs and RECK) and inducer (EMMPRIN)

BACKGROUND

Calcifying cyst odontogenic tumour (CCOT) is a rare benign cystic neoplasm of odontogenic origin. MMPs are responsible for extracellular matrix remodelling and, together their inhibitors and inducer, determinate the level of its turnover in pathological processes, leading to an auspicious microenvironment for tumour development. Thus, our goal was to evaluate matrix metalloproteinases (MMPs-2, -7, -9 and -14), their inhibitors (TIMPs-2, -3, -4 and RECK) and its inductor (EMMPRIN) expression in CCOT.

MATERIALS AND METHODS

We used 18 cases of CCOT submitted to immunolocalization of the target proteins and analysed in both neoplastic odontogenic epithelial and stromal compartments.

RESULTS

All molecules evaluated were expressed in both compartments in CCOT. In epithelial layer, immunostaining for MMPs, TIMPs, RECK and EMMPRIN was found in basal, suprabasal spindle and stellate cells surrounding ghost cells and ghost cells themselves, except for MMP-9 and TIMP-2 which were only expressed by ghost cells. In stromal compartment, extracellular matrix, mesenchymal (MC) and endothelial cells (EC) were positive for MMP-2, -7, TIMP-3 and -4, while MMP-9, TIMP-2 and RECK were positive only in MC and MMP-14 only in EC. Statistical significance difference was found between both compartments for MMP-9 (P < 0.001), RECK (P = 0.004) and EMMPRIN (P < 0.001), being more expressed in epithelium than in stroma. Positive correlation between both stromal EMMPRIN and RECK expression was found (R = 0.661, P = 0.003).

CONCLUSIONS

We concluded that these proteins/enzymes are differentially expressed in both epithelium and stroma of CCOT, suggesting an imbalance between MMPs and their inducer/inhibitors may contribute on the tumour behaviour.

Current Concepts and Occurrence of Epithelial Odontogenic Tumors: II. Calcifying Epithelial Odontogenic Tumor Versus Ghost Cell Odontogenic Tumors Derived from Calcifying Odontogenic Cyst

Calcifying epithelial odontogenic tumors (CEOTs) and ghost cell odontogenic tumors (GCOTs) are characteristic odontogenic origin epithelial tumors which produce calcifying materials from transformed epithelial tumor cells. CEOT is a benign odontogenic tumor composed of polygonal epithelial tumor cells that show retrogressive calcific changes, amyloid-like deposition, and clear cytoplasm. Differentially, GCOTs are a group of transient tumors characterized by ghost cell presence, which comprise calcifying cystic odontogenic tumor (CCOT), dentinogenic ghost cell tumor (DGCT), and ghost cell odontogenic carcinoma (GCOC), all derived from calcifying odontogenic cysts (COCs). There is considerable confusion about COCs and GCOTs terminology, but these lesions can be classified as COCs or GCOTs, based on their cystic or tumorous natures, respectively. GCOTs include ameloblastomatous tumors derived from dominant odontogenic cysts classified as CCOTs, ghost cell-rich tumors producing dentinoid materials as DGCTs, and the GCOT malignant counterpart, GCOCs. Many authors have reported CEOTs and GCOTs variably express keratins, β-catenin, BCL-2, BSP, RANKL, OPG, Notch1, Jagged1, TGF-β, SMADs, and other proteins. However, these heterogeneous lesions should be differentially diagnosed to allow for accurate tumor progression and prognosis prediction.

Predictive factors of potential malignant transformation in recurrent calcifying cystic odontogenic tumor: review of the literature

Calcifying cystic odontogenic tumor (CCOT) demonstrates considerable diversity in histopathology and clinical behavior. Ghost cell odontogenic carcinoma (GCOC) is the rare malignant counterpart of CCOT and it frequently arises from malignant transformation of a recurrent CCOT. In this paper, we present a case of CCOT and discuss its distinct histopathologic features in recurrence. Then, we will have a review on clinical, histopathological, and immunohistochemical aspects of GCOC in the literature. Predictive factors of malignant transformation in a benign CCOT will also be discussed.

Variable Ki67 proliferative index in 65 cases of nodular fasciitis, compared with fibrosarcoma and fibromatosis

Abstract

Nodular fasciitis is the most common pseudosarcomatous lesion of soft tissue. Ki67 was considered as a useful marker for distinguishing some benign and malignant lesions. To study the usefulness of Ki67 in diagnosis of nodular fasciitis, the expression of Ki67 was examined by using immunostaining in 65 nodular fasciitis specimens, 15 desmoid fibromatosis specimens and 20 fibrosarcoma specimens. The results showed that there was a variable Ki67 index in all 65 cases of nodular fasciitis, and the mean labeling index was 23.71±15.01%. In majority (70.77%) of all cases,the index was ranged from 10% to 50%, in 6.15% (4/65) of cases the higher Ki67 index (over 50%) could be seen. The Ki67 proliferative index was closely related to duration of lesion, but not to age distribution, lesion size, sites of lesions and gender. Moreover, the mean proliferative index in desmoid fibromatosis and fibrosarcoma was 3.20±1.26% and 26.15±3.30% respectively. The mean Ki67 index of nodular fasciitis was not significantly lower than fibrosarcoma, but higher than desmoid fibromatosis. The variable and high Ki67 index in nodular fasciitis may pose a diagnostic challenge. We should not misdiagnose nodular fasciitis as a sarcoma because of its high Ki67 index. The recurrence of nodular fasciitis is rare; and the utility of Ki67 immunostaining may be not suitable for recurrence assessment in nodular fasciitis.

Virtual slides

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/4782335818876666

Distant metastasis of intraosseous dentinogenic ghost cell tumour to the donor site of a bone graft

A dentinogenic ghost cell tumour (DGCT) is an extremely rare odontogenic tumour which is considered as a solid, neoplastic variant of calcifying odontogenic cyst. Intraosseous DGCTs are more aggressive than extraosseous DGCTs and have a high propensity for local recurrence. This report describes a case of a diagnosis of recurrent DGCT at the primary site and a distant donor site. A 25-year-old female patient visited a dental hospital for a complaint of facial swelling for the previous month. Incisional biopsy was performed and the specimen was diagnosed as DGCT. Partial mandibulectomy for tumour resection and iliac bone graft was performed. 2 years later, the tumour recurred on the mandible and iliac bone. The recurrent lesion on the donor site was diagnosed as metastasized DGCT. This report highlights the possibility of distant metastasis occurring at a graft donor site.

Intraosseous carcinoma of the jaws: a clinicopathologic review. Part II: Odontogenic carcinomas

This is the second of a 3-part review of the clinicopathologic features of intraosseous carcinoma of the jaws (IOCJ). This part deals with odontogenic carcinomas, rare entities that are difficult to evaluate because of changes in classification/nomenclature, lack of standardized diagnostic criteria, and variable consistency of the existing literature. Endorsing a critical approach, problems are addressed and areas of uncertainty are highlighted. As in part I, we emphasize histopathologic features from a diagnostic point of view and also question the existence of some "distinct" entities.

Comparative immunohistochemical study of ameloblastoma and ameloblastic carcinoma

OBJECTIVE

Ameloblastic carcinoma combines the histologic features of ameloblastoma with cytologic atypia, regardless of whether it has metastasized. Because of its rarity, there are few immunoprofile studies of ameloblastic carcinoma and few comparative studies of ameloblastic carcinoma and ameloblastoma. In this study, we compared the expression levels of cytokeratins (CKs), matrix metalloproteinases (MMPs), and Ki-67 between ameloblastoma and ameloblastic carcinoma, and assessed the usefulness of these markers for differentiating the tumors.

STUDY DESIGN

We assessed CK7, CK14, CK18, CK19, MMP-2, MMP-9, and Ki-67 expression by immunohistochemistry in 10 cases of ameloblastoma and 7 cases of ameloblastic carcinoma and then compared expression patterns between the 2 groups.

RESULTS

Immunostaining for CK14 and CK19 was diffuse and strongly positive in both tumor types, but staining for CK7 was focally positive in only 1 case of ameloblastoma and absent in all cases of ameloblastic carcinoma. However, there was a significant difference in CK18 expression between the 2 tumors (P = .000). Whereas 80% of ameloblastomas showed negative reactivity for CK18, most cases of ameloblastic carcinomas showed a moderate to strong intensity of immunostaining for CK18. Regarding the expression of MMPs, there were significant differences in parenchymal MMP-2 and stromal MMP-9 expression between the 2 tumors. Compared to ameloblastoma, ameloblastic carcinoma showed significantly strong expression of MMP-2 in parenchymal cells (P = .001) and MMP-9 in stromal cells (P = .013). However, there were no differences in MMP-2 expression of stromal cells and MMP-9 expression of parenchymal cells between ameloblastoma and ameloblastic carcinoma. The mean Ki-67 labeling index (LI) of ameloblastic carcinomas was 17.21%, which was significantly higher than that of ameloblastomas (3.57%; P = .002).

CONCLUSIONS

The significant expression of CK18, parenchymal MMP-2, stromal MMP-9, and Ki-67 could provide useful markers for differentiating ameloblastic carcinoma from ameloblastoma.

Immunohistochemical analysis of p53 and PCNA expression in calcifying odontogenic cyst

Calcifying odontogenic cyst (COC) is a developmental odontogenic cyst in the jaw. Because of its diverse histopathologic features and biological behavior, there has long been confusion with regard to its nature as a cyst or neoplasm. This study evaluated the proliferative activity of 57 COC samples, including simple cyst (10 cases), cystic neoplasm (34 cases), solid neoplasm (6 cases) and combined lesion (7 cases) by p53 and PCNA immunohistochemical staining. For assessment of p53 and PCNA positivity, the number of positively stained cells with brown-stained nuclei was counted in 1000 cells from each sample. p53 and PCNA expression in the solid neoplasm subtype were significantly higher when compared to cystic neoplasm and simple cyst (P < 0.05). The lowest p53 and PCNA expression was found in the simple cyst subtype. p53 and PCNA expression in the basal and suprabasal layers was significantly higher in the solid subtype when compared to others, and the difference between COC groups was significant. The results demonstrated that within benign types of COC, the amount of p53 and PCNA in proliferative epithelium is significantly higher when compared to non-proliferative epithelium. p53 and PCNA markers are possible parameters for differentiation of COC subtypes.

Preventive effect of Coptis chinensis and berberine on intestinal injury in rats challenged with lipopolysaccharides

Coptis chinensis has been used in traditional Chinese medicine to treat inflammatory symptoms. Berberine is the main alkaloid compound of C. chinensis. This study utilized a typical lipopolysaccharide (LPS) injured model to investigate the effects of C. chinensis aqueous extract (CCAE) and berberine (major active ingredient in CCAE) in the gut-derived sepsis. In rats, pretreatment with different doses of berberine (30 or 120 mg/kg bw, i.g.; BBR30 or BBR120) or CCAE (containing 9.9% berberine; 300 mg/kg bw, i.g.; CCAE300) prior to the administration of LPS (20 mg/kg bw, i.p.) significantly suppressed the increased tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and nitrite oxide (NO) in plasma as well as the activation of toll-like receptor 4 (TLR4) and nuclear factor-κB (NF-κB) in ileum. In addition, CCAE300 and BBR30 markedly elevated the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px); significantly prevented the increased malondialdehyde (MDA), NO and villi injury in ileum compared with the negative control. Collectively, CCAE300 and BBR30 reduced the LPS-induced intestinal damage by elevating the activities of SOD and GSH-Px and by suppressing the activation of TLR4 and NF-κB in ileum. These results indicate that CCAE and berberine are promising agents for preventing sepsis and its complications.

Immunoexpression of Ki67, proliferative cell nuclear antigen, and Bcl-2 proteins in a case of ameloblastic fibrosarcoma

Ameloblastic fibrosarcoma (AFS), regarded as the malignant counterpart of the benign ameloblastic fibroma, is an extremely rare odontogenic neoplasm with only 68 cases reported in the English literature up to 2009. It is composed of a benign odontogenic epithelium, resembling that of ameloblastoma, and a malignant mesenchymal part exhibiting features of fibrosarcoma. Due to the rarity of the lesion, little is known about its molecular pathogenesis; therefore, in the current study, we sought to evaluate the immunoexpression of Ki67, proliferative cell nuclear antigen, and Bcl-2 proteins in AFS, comparing the results obtained with its benign counterpart, as well as to report a new case of this rare entity affecting a 19-year-old female patient. The results obtained revealed that all the proteins evaluated were overexpressed in the malignant mesenchymal portion of AFS if compared with ameloblastic fibroma, suggesting that nuclear proliferative factors such as Ki67 and proliferative cell nuclear antigen, in association to histopathologic features, may be useful markers for identifying the malignancy and that, despite the lack of molecular analysis in the case reported, Bcl-2 alteration may play a role in AFS pathogenesis.