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Urs AB, Kumar P, Singh S, Mohanty S, Chaudhary Z. Odontogenic keratocysts: A retrospective histopathological study. Natl J Maxillofac Surg 2024; 15:136-141. [PMID: 38690256 PMCID: PMC11057584 DOI: 10.4103/njms.njms_211_22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Revised: 03/23/2023] [Accepted: 04/27/2023] [Indexed: 05/02/2024] Open
Abstract
Introduction Odontogenic keratocyst (OKC) is an aggressive recurrent cyst with intriguing features. Various factors such as the surgical procedure are involved, and certain histological features contribute to its recurrence. We assessed the clinical, radiographic, and histopathological data of OKCs to better comprehend the true nature of this cyst. Material and Methods A total of 58 lesions including four cases in association with nevoid basal cell carcinoma syndrome (NBCCS) were assessed. Radiographic features and histopathological features within the epithelium and capsule were assessed. Results 72% of cases were seen in males and 28% in females. 43% of cases were seen in the mandibular ramus, and 65% exhibited unilocular radiolucency. 95% showed true parakeratinization. Cuboidal basal cell morphology was seen in 41.3% of cases and reversal of polarity in 60%. Basal budding, rete pegs, and mitosis were also observed within the epithelium. The epithelium showed separation at the subbasal level and suprabasal levels in 55 (94.9%) cases. Conclusion Features such as basal cell budding, suprabasal mitotic activity, suprabasal split, localized inflammation, subepithelial hyalinization, and satellite cysts were commonly associated with recurrent cysts. Many newer genetic and molecular hypotheses have generated path-breaking contributions to the understanding of the biology of OKC. With the guidance and help of such factors, improved post-surgery results can be anticipated.
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Affiliation(s)
- Aadithya Basavaraj Urs
- Department of Oral Pathology and Microbiology, Maulana Azad Institute of Dental Sciences, New Delhi, India
| | - Priya Kumar
- Department of Oral Pathology and Microbiology, Maulana Azad Institute of Dental Sciences, New Delhi, India
| | - Shivani Singh
- Department of Radiation Oncology, Lok Nayak Jai Prakash Narayan Hospital, New Delhi, India
| | - Sujata Mohanty
- Department of Oral and Maxillofacial Surgery, Maulana Azad Institute of Dental Sciences, New Delhi, India
| | - Zainab Chaudhary
- Department of Oral and Maxillofacial Surgery, Maulana Azad Institute of Dental Sciences, New Delhi, India
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Laureano NK, Bernardi L, Bundrich L, Brand LM, Visioli F, Lamers ML, Rados PV. Development of an
in vitro
model to study tooth cystogenesis. Int Endod J 2019; 52:1750-1757. [DOI: 10.1111/iej.13193] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Accepted: 07/24/2019] [Indexed: 01/22/2023]
Affiliation(s)
- N. K. Laureano
- Basic Research Center, Dentistry School Federal University of Rio Grande do Sul Porto AlegreBrazil
| | - L. Bernardi
- Basic Research Center, Dentistry School Federal University of Rio Grande do Sul Porto AlegreBrazil
- Department of Morphological Sciences Federal University of Rio Grande do Sul Porto AlegreBrazil
| | - L. Bundrich
- Basic Research Center, Dentistry School Federal University of Rio Grande do Sul Porto AlegreBrazil
| | - L. M. Brand
- Basic Research Center, Dentistry School Federal University of Rio Grande do Sul Porto AlegreBrazil
| | - F. Visioli
- Department of Oral Pathology, Dentistry School Federal University of Rio Grande do Sul Porto Alegre Brazil
| | - M. L. Lamers
- Department of Morphological Sciences Federal University of Rio Grande do Sul Porto AlegreBrazil
| | - P. V. Rados
- Department of Oral Pathology, Dentistry School Federal University of Rio Grande do Sul Porto Alegre Brazil
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Abstract
The aims of this study were to determine the presence and distribution of vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptor-2 (VEGFR2) in dentigerous cysts compared with normal dental follicles as a control tissue and to evaluate endothelial cells and proliferating cells as indicators of angiogenic activity in these tissues.Twenty specimens histologically diagnosed as dentigerous cysts and 20 dental follicle specimens were included. Immunohistochemistry (IHC) using anti-VEGF and anti-VEGFR2 antibodies stained for the growth factor and its receptor, while anti-CD34 and anti-CD146 antibodies were used to identify endothelial cells. Anti-proliferating cell nuclear antigen (PCNA) antibody detected proliferating cells within the specimens. Slides were examined microscopically and results evaluated using kappa statistics, negative binomial regression and ordinal logistic regression.The mean age for patients with dentigerous cysts was 23 years and they were more common in males. Proteins for VEGF, VEGFR2, PCNA, CD34, and CD146 were expressed in all dentigerous cysts and dental follicles. VEGF and VEGFR2 were expressed on several cell types within the tissues, however there was a significantly greater percentage of positive staining in dentigerous cysts compared with dental follicles (odds ratio = 31.24, p < 0.001). CD34(+), CD146(+), and PCNA(+) cells were observed in both dentigerous cysts and dental follicles but for all markers there were significantly more positive cells in dentigerous cysts (p < 0.001); this was especially evident in cases associated with inflammation. PCNA was seen in most endothelial cells lining small thin walled blood vessels suggesting endothelial proliferation. There was a high level of intra- and inter-examiner agreement (kappa 0.77 and 0.75, respectively).VEGF and VEGFR2 and angiogenic activity are present in dental follicles and dentigerous cysts and may contribute to local bone resorption for tooth eruption or the development and progression of dentigerous cysts.
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Bernardi L, Visioli F, Nör C, Rados PV. Radicular Cyst: An Update of the Biological Factors Related to Lining Epithelium. J Endod 2015; 41:1951-61. [PMID: 26603778 DOI: 10.1016/j.joen.2015.08.036] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Revised: 08/16/2015] [Accepted: 08/30/2015] [Indexed: 12/12/2022]
Abstract
INTRODUCTION Radicular cysts are common lesions in daily dentistry practice. However, the mechanisms related to epithelial lining formation and cavity growth are not fully understood. Therefore, the purpose of this article was to review the biological factors implicated in these process. METHODS Literature was selected through a search of PubMed electronic databases matching the following key words in the title or abstract: "cyst" OR "granuloma" OR "abscess" AND "radicular" OR "apical" OR "periapical" AND "epithelium" OR "epithelial" OR "epithelial lining." The PubMed database was searched for articles published between 1975 and 2014. Only English language was applied to the search. RESULTS The literature search yielded a total of 187 articles. After duplicate references were discarded, a subsequent search at the title and abstract level revealed 42 articles for full-text reading. The articles were categorized into 5 main subtopics: (1) cell proliferation, cell cycle, and apoptosis; (2) extracellular matrix constituents; (3) inflammatory components; (4) bone metabolic factors and; (5) others. These subtopics described the characteristics of radicular cysts focusing on the epithelial tissue effects. CONCLUSIONS Several factors from different sources (epithelial cells, stromal cells, extracellular matrix, and bone matrix) were implicated on apical cyst pathogenesis. Probably a combination of many factors involving an epithelial-stromal interaction is responsible for the sustenance and growth of apical cysts.
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Affiliation(s)
- Lisiane Bernardi
- Basic Research Center, Dentistry School, Federal University of Rio Grande do Sul, Rio Grande do Sul, Brazil
| | - Fernanda Visioli
- Department of Oral Pathology, Dentistry School, Federal University of Rio Grande do Sul, Rio Grande do Sul, Brazil
| | - Carolina Nör
- University Hospital Research Center, Federal University of Rio Grande do Sul, Rio Grande do Sul, Brazil
| | - Pantelis Varvaki Rados
- Department of Oral Pathology, Dentistry School, Federal University of Rio Grande do Sul, Rio Grande do Sul, Brazil.
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Márton IJ, Kiss C. Overlapping Protective and Destructive Regulatory Pathways in Apical Periodontitis. J Endod 2014; 40:155-63. [DOI: 10.1016/j.joen.2013.10.036] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Revised: 09/26/2013] [Accepted: 10/24/2013] [Indexed: 02/06/2023]
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Razavi SM, Hasheminia D, Mehdizade M, Movahedian B, Keshani F. The relation of pericoronal third molar follicle dimension and bcl-2/ki-67 expression: An immunohistochemical study. Dent Res J (Isfahan) 2013; 9:S26-31. [PMID: 23814558 PMCID: PMC3692196 DOI: 10.4103/1735-3327.107931] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Background: Most common impacted teeth are the mandibular third molars and decision about extraction of them is usually controversial. The presence of pericoronal pathologic changes is an acceptable reason for removal of impacted teeth. Differences in the proliferation rate and apoptosis of odontogenic epithelial cells may influence on the formation of odontogenic epithelial lesions. Therefore, the aim of the present study is to evaluate the immunohistochemical expression of the bcl-2 apoptosis-inhibiting protein and the cell-cycle-related ki-67 antigen in pericoronal follicle of impacted third molars with ≥2.5 mm and <2.5 mm radiolucency. Materials and Methods: This was a cross-sectional study that 20 follicles with <2.5 mm radiolucency and 20 follicles with ≥2.5 mm radiolucency were selected by a professional radiologist in digital panoramic radiographs and then referred to a surgeon. Formalin fixed paraffin-embedded tissues were immunohistochemical analyzed for immunoreactivity of bcl-2 protein and ki-67 antigen. The data was analyzed using logistic regression, Spearman correlation coefficient and t-test and Mann-Whitney. P<0.05 was considered significant. Results: The findings showed correlation between size of the third molar's follicles and expression of bcl-2 protein (P < 0.001, r = 0.556) but there was no correlation between size of third molar's follicles and staining with ki-67 antigen (P = 0.546, r = 0.098). The follicles with radiolucency ≥2.5 mm showed increased immunoreactivity for bcl-2 protein. Conclusion: The results of study suggest that impacted third molars with radiolucency ≥2.5 mm may be associated with deregulation of cell death, indicated with increased expression of the anti- apoptotic protein bcl-2, while cell proliferation (ki-67) does not seem to play a significant role.
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Affiliation(s)
- Seyed Mohammad Razavi
- Torabinejad Dental Research Center and Department of Oral and Maxillofacial Pathology, School of Dentistry, Isfahan University of Medical Sciences, Isfahan, Iran
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Keinan D, Cohen RE. The Significance of Epithelial Rests of Malassez in the Periodontal Ligament. J Endod 2013; 39:582-7. [DOI: 10.1016/j.joen.2013.01.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2012] [Revised: 01/18/2013] [Accepted: 01/30/2013] [Indexed: 11/26/2022]
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Pazdera J, Kolar Z, Zboril V, Tvrdy P, Pink R. Odontogenic keratocysts/keratocystic odontogenic tumours: biological characteristics, clinical manifestation and treatment. Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub 2012; 158:170-4. [PMID: 23073530 DOI: 10.5507/bp.2012.048] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2011] [Accepted: 04/13/2012] [Indexed: 01/25/2023] Open
Abstract
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.
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Affiliation(s)
- Jindrich Pazdera
- Department of Oral and Maxillofacial Surgery, Faculty of Medicine and Dentistry, Palacky University Olomouc and University Hospital Olomouc, Czech Republic
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Santos LCS, Vilas Bôas DS, Oliveira GQV, Ramos EAG, Gurgel CAS, Santos JND. Histopathological study of radicular cysts diagnosed in a Brazilian population. Braz Dent J 2011; 22:449-54. [DOI: 10.1590/s0103-64402011000600002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2011] [Accepted: 10/01/2011] [Indexed: 11/22/2022] Open
Abstract
The aim of this study was to investigate the histopathological features of radicular cysts (RCs) diagnosed in a Brazilian population. Seventy-three cases of RCs, from a total of 1480 biopsies diagnosed between 2001 and 2008 at the Laboratory of Oral Surgical Pathology of the Dental School of the Federal University of Bahia were investigated regarding their histopathological features. Morphological results showed that exocytosis (n=50), spongiosis (n=40), acanthosis (n=28), atrophic epithelium (n=27) and apoptotic bodies (n=21) were the most common findings. Other morphological findings included: foamy macrophages (n=10), Russell’s bodies (n=7), cholesterol crystals (n=7) and glandular-like odontogenic epithelial rests (n=1). Evidence of exogenous material was seen in 16 samples. It was concluded that the clinical and histopathological findings observed in Brazilian patients were comparable with those described for other populations.
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da Silva Baumgart C, da Silva Lauxen I, Filho MS, de Quadros OF. Epidermal growth factor receptor distribution in pericoronal follicles: relationship with the origin of odontogenic cysts and tumors. ACTA ACUST UNITED AC 2006; 103:240-5. [PMID: 17234542 DOI: 10.1016/j.tripleo.2005.11.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2005] [Revised: 11/15/2005] [Accepted: 11/15/2005] [Indexed: 11/29/2022]
Abstract
OBJECTIVE Investigate the distribution of epidermal growth factor receptor (EGFR) in pericoronal follicles as a predictor of progression to odontogenic cysts and tumors. STUDY DESIGN Immunohistochemical EGFR staining patterns (membrane-only, cytoplasm-only, or combined membrane and cytoplasmic staining) in the reduced enamel epithelium and nests of odontogenic epithelium associated with follicles of impacted molar teeth were evaluated. The staining pattern of 20 specimens of pericoronal follicle was compared with that of 16 normal oral mucosa samples and to squamous cell carcinoma samples. RESULTS Combined membrane and cytoplasmic staining was observed for normal oral mucosa mostly in proliferating layers (basal and suprabasal), decreasing in intensity toward the surface. Seven epithelial nests presented membrane-only staining, and the majority presented either a cytoplasm-only or a combined staining pattern. The staining patterns observed in reduced enamel epithelium were cytoplasm-only and combined. CONCLUSION EGFR membrane-only staining may be an indicator of increased potential for epithelial nests to become odontogenic cysts or tumors.
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Affiliation(s)
- Cristina da Silva Baumgart
- Graduate Program in Dentistry, Oral Pathology, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
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Kolár Z, Geierová M, Bouchal J, Pazdera J, Zboril V, Tvrdý P. Immunohistochemical analysis of the biological potential of odontogenic keratocysts. J Oral Pathol Med 2006; 35:75-80. [PMID: 16430736 DOI: 10.1111/j.1600-0714.2006.00382.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND The aim of this study was to analyse the usefulness of detecting important apoptosis and proliferation markers in assessing the biological potential of odontogenic keratocysts (OKC) and thus selecting the optimal diagnostic algorithm for these lesions. METHODS Indirect immunohistochemistry and relevant statistical methods were used for analysis of formalin-fixed and paraffin-embedded samples from 98 patients. RESULTS Nevoid basal cell carcinoma syndrome (NBCCS) keratocysts were characterized by higher expression of Bcl-2, p27Kip1 and c-erbB-2 as well as by lower proliferative activity measured by Ki-67 in basal cell epithelium and by a lower inflammatory response in comparison with sporadic keratocysts. Dentigerous, radicular and non-specified odontogenic cysts differed from both NBCCS and sporadic keratocysts in a wide spectrum of apoptosis and/or cell cycle-related protein expressions, higher proliferation in the basal cell layer, and vice versa, lower proliferation in the suprabasal cell layer. CONCLUSIONS The NBCCS keratocysts have a different immunophenotype from sporadic keratocysts and both types are distinguishable from dentigerous, radicular and non-specified odontogenic cysts. These findings confirm the separate biological potential of these lesions and the results of the immunohistochemical analysis have diagnostic and prognostic implications.
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Affiliation(s)
- Zdenek Kolár
- Institute of Pathology and Laboratory of Molecular Pathology, Faculty of Medicine, Palacký University, Olomouc, Czech Republic.
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Loyola AM, Cardoso SV, Lisa GS, Oliveira LJ, Mesquita RA, Carmo MAV, Aguiar MCF. Apoptosis in epithelial cells of apical radicular cysts. Int Endod J 2005; 38:465-9. [PMID: 15946267 DOI: 10.1111/j.1365-2591.2005.00971.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIM To investigate the occurrence of apoptotic cell death in the epithelium of radicular cysts and to compare its frequency in lesions presenting a distinct functional state. METHODOLOGY Twenty radicular cysts were selected and arranged into two groups with 10 lesions in each group: atrophic (quiescent) and hyperplastic (active) epithelium. Morphologic investigations of apoptosis were conducted by means of optic microscopy in haematoxylin and eosin slides. Immunohistochemical techniques to detect the bcl-2 protein were carried out by streptavidin-biotin-peroxidase assay. In both instances, 30 sequential high-power microscopic fields were observed to determine apoptotic (AI) and bcl-2 immunostaining (bcl-2I) indexes. The presence of AI and bcl-2I within the two groups was compared using the t-test. Correlation between the AI and the bcl-2I was investigated using the Spearman test. RESULTS Apoptosis was detected in the epithelium of all cysts. Higher AI levels were found in lesions with an atrophic (0.17 +/- 0.19) rather than a hyperplastic (0.10 +/- 0.10) epithelium. The same was found for the bcl-2I levels (0.06 +/- 0.03 vs. 0.04 +/- 0.01, respectively). However, these differences were not statistically significant. A positive and significant correlation was found between AI and bcl-2I. CONCLUSIONS Apoptosis was always present in the epithelium of the lesions and was more frequent in lesions with atrophic (quiescent) epithelium.
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Affiliation(s)
- A M Loyola
- Oral Pathology Laboratory, School of Dentistry, Federal University of Uberlândia, Brazil
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Kumamoto H, Takahashi N, Ooya K. K-Ras gene status and expression of Ras/mitogen-activated protein kinase (MAPK) signaling molecules in ameloblastomas. J Oral Pathol Med 2004; 33:360-7. [PMID: 15200485 DOI: 10.1111/j.1600-0714.2004.00141.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND To clarify the roles of rat sarcoma (Ras)/mitogen-activated protein kinase (MAPK) signaling pathway in oncogenesis and cytodifferentiation of odontogenic tumors, K-Ras gene status and expression of Ras, Raf1, MAPK/extracellular signal-regulated kinase (ERK) kinase (MEK)1, and ERK1/2 proteins were analyzed in ameloblastomas as well as in tooth germs. METHODS Paraffin sections of 10 tooth germs and 46 benign and 6 malignant ameloblastomas were examined immunohistochemically for the expression of K-Ras, Raf1, MEK1, and ERK1/2. Frozen tissue samples of 22 benign ameloblastomas and 1 malignant (metastasizing) ameloblastoma were analyzed by direct DNA sequencing to detect K-Ras gene alteration. RESULTS Immunohistochemical reactivity for K-Ras, Raf1, MEK1, and ERK1/2 was detected in both normal and neoplastic odontogenic epithelium, and these molecules were reactive chiefly with odontogenic epithelial cells neighboring the basement membrane. Plexiform ameloblastomas showed slightly stronger expression of these Ras/MAPK signaling molecules than follicular ameloblastomas. Keratinizing cells and granular cells showed decreased reactivity for the signaling molecules. Basal cell ameloblastomas showed slightly stronger reactivity for the signaling molecules than did the other subtypes. K-Ras immunoreactivity in malignant ameloblastomas was lower than that in dental lamina of tooth germs. Direct DNA sequencing showed a GGT to GCT point mutation at codon 12 of K-Ras gene in one ameloblastoma. CONCLUSION Expression of K-Ras, Raf1, MEK1, and ERK1/2 in tooth germs and ameloblastomas suggests that Ras/MAPK signaling pathway functions to regulate cell proliferation and differentiation in both normal and neoplastic odontogenic epithelium. K-Ras gene status implied that K-Ras mutations might play a minor role in oncogenesis of odontogenic epithelium.
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Affiliation(s)
- Hiroyuki Kumamoto
- Division of Oral Pathology, Department of Oral Medicine and Surgery, Tohoku University Gradudate School of Dentistry, Sendai, Japan.
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