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Archives of Oral Biology Aug 2022This article aims to systematically and comprehensively discuss molecular biology-related progress and targeted therapeutic strategies for ameloblastoma, which are... (Review)
Review
OBJECTIVE
This article aims to systematically and comprehensively discuss molecular biology-related progress and targeted therapeutic strategies for ameloblastoma, which are expected to be helpful for the diagnosis and treatment of ameloblastoma.
DESIGN
A comprehensive review of scientific literature relevant to ameloblastoma, including the latest classification, global epidemiology, molecular biology advances, and targeted therapy.
RESULTS
Among the 156 articles cited, a total of 20 non-coding RNAs, 13 genes, 27 proteins, and 8 pathways were involved, which play a variety of roles in ameloblastoma. These roles include participation in the biological behaviours of ameloblastoma migration, differentiation, and apoptosis; detection of ameloblastoma proliferative properties; detection of ameloblastoma angiogenesis; and identification of ameloblastoma carcinogenesis.
CONCLUSIONS
At present, some progress has been made in molecular biology and targeted therapy for ameloblastoma involving BRAF and SMO genes. The related non-coding RNAs, genes, proteins, and pathways involved in this review provide new ideas and directions for the occurrence and development of ameloblastoma and have the potential to become new gene therapy targets.
Topics: Ameloblastoma; Humans; Molecular Biology; Mutation; Proto-Oncogene Proteins B-raf
PubMed: 35597128
DOI: 10.1016/j.archoralbio.2022.105454 -
Indian Journal of Dental Research :... 2022Ameloblastoma is a benign, locally aggressive neoplasm that needs extensive surgical resection. The goal of this article is to obtain an in-depth review of benign... (Review)
Review
Ameloblastoma is a benign, locally aggressive neoplasm that needs extensive surgical resection. The goal of this article is to obtain an in-depth review of benign ameloblastomas to determine the available level of evidence and the possible benefit of targeted therapeutics for the treatment of ameloblastoma and BRAF V600E mutation in ameloblastoma. An electronic literature search was conducted according to PRISMA guidelines in PubMed/MEDLINE, EBSCO, and Web of Science for eligible studies published between 1975 and 2021. The systematic review is registered with INPLASY (INPLASY202260018). The review included 2 case series and 17 case reports. The histopathological type, anatomic location, expression of BRAF mutation, additional mutations, and molecular-targeted therapies of the 19 reviewed articles were summarized and tabulated. Interestingly, the majority of the primary site of ameloblastoma was located in the mandible (80.9%) compared to the maxilla (17%). The tumour size was reported in nine of the included studies. Most of the included studies in the review exhibited ameloblastoma with BRAF V600E mutations and responded to molecular-targeted therapies. Molecular therapies employing BRAF and/or MEK inhibitors in ameloblastoma with BRAF V600E mutations proved to be an appropriate treatment based on the limited available evidence. It is essential further to deepen our understanding at the clinical and molecular level to enhance the precision of management of ameloblastoma.
Topics: Humans; Ameloblastoma; Molecular Targeted Therapy; Mutation; Proto-Oncogene Proteins B-raf
PubMed: 36656197
DOI: 10.4103/ijdr.ijdr_456_22 -
Modern Pathology : An Official Journal... Nov 2022Adenoid ameloblastoma is a very rare benign epithelial odontogenic tumor characterized microscopically by epithelium resembling conventional ameloblastoma, with...
Adenoid ameloblastoma is a very rare benign epithelial odontogenic tumor characterized microscopically by epithelium resembling conventional ameloblastoma, with additional duct-like structures, epithelial whorls, and cribriform architecture. Dentinoid deposits, clusters of clear cells, and ghost-cell keratinization may also be present. These tumors do not harbor BRAF or KRAS mutations and their molecular basis appears distinct from conventional ameloblastoma but remains unknown. We assessed CTNNB1 (beta-catenin) exon 3 mutations in a cohort of 11 samples of adenoid ameloblastomas from 9 patients. Two of the 9 patients were female and 7 male and in 7/9 patients the tumors occurred in the maxilla. Tumors of 4 of these 9 patients harbored CTNNB1 mutations, specifically p.Ser33Cys, p.Gly34Arg, and p.Ser37Phe. Notably, for one patient 3 samples were analyzed including the primary tumour and two consecutive recurrences, and results were positive for the mutation in all three tumors. Therefore, 6/11 samples tested positive for the mutation. In the 6 mutation-positive samples, ghost cells were present in only 2/6, indicating beta-catenin mutations are not always revealed by ghost cell formation. Dentinoid matrix deposition was observed in 5/6 mutation-positive samples and clear cells in all 6 cases. None of the cases harbored either BRAF or KRAS mutations. Beta-catenin immunoexpression was assessed in the samples of 8 patients. Except for one wild-type case, all cases showed focal nuclear expression irrespective of the mutational status. Together with the absence of BRAF mutation, the detection of beta-catenin mutation in adenoid ameloblastomas supports its classification as a separate entity, and not as a subtype of ameloblastoma. The presence of this mutation may help in the diagnosis of challenging cases.
Topics: Humans; Male; Female; Ameloblastoma; beta Catenin; Proto-Oncogene Proteins B-raf; Adenoids; Proto-Oncogene Proteins p21(ras); Odontogenic Tumors; Mutation
PubMed: 35840721
DOI: 10.1038/s41379-022-01125-4 -
Journal of Pharmacy & Bioallied Sciences Jul 2023Desmoplastic ameloblastoma (DA) is a rare variant of conventional ameloblastoma. It accounts for only 4%-13% of all ameloblastomas. DA was included in the World Health...
Desmoplastic ameloblastoma (DA) is a rare variant of conventional ameloblastoma. It accounts for only 4%-13% of all ameloblastomas. DA was included in the World Health Organization Classification of Head and Neck Tumors (WHO-2005) as a variant of ameloblastoma with specific clinical, imaging, and histological features. The desmoplastic variant of ameloblastoma usually appears in the anterior and premolar regions as a mixed radiolucent and radiopaque lesion, sometimes resembling a benign fibro-osseous lesion.Ameloblastoma is a locally aggressive tumor that may cause recurrence and in rare cases, malignant transformation with repeated postsurgical recurrences. In this paper, we present a case of a 28-year-old female with swelling in the left upper jaw, a biopsy of which turned out to be DA.
PubMed: 37654261
DOI: 10.4103/jpbs.jpbs_44_23 -
Head and Neck Pathology Mar 2023A recent systematic review published in Head and Neck Pathology found that 3.8% of dentinogenic ghost cell tumors harbor duct-like/ cribriform architecture. Herein we... (Review)
Review
BACKGROUND
A recent systematic review published in Head and Neck Pathology found that 3.8% of dentinogenic ghost cell tumors harbor duct-like/ cribriform architecture. Herein we discuss this finding regarding the differential diagnosis of this tumor with adenoid ameloblastoma.
METHODS
A critical review of some microscopic findings reported in a recent paper published in the Head and Neck Pathology Journal was done.
RESULTS
Although there are overlapping microscopic features with dentinogenic ghost cell tumor, adenoid ameloblastoma is distinguished by the combination of duct-like structures and whorls/morules. In our opinion, at least some cases previously diagnosed as dentinogenic ghost cell tumors may now be more accurately classified as adenoid ameloblastoma.
CONCLUSION
We conclude that a reassessment of dentinogenic ghost cell tumor cases using the diagnostic criteria proposed by the new WHO classification of Head and Neck Tumors (2022) is warranted.
Topics: Humans; Ameloblastoma; Odontogenic Tumors; Adenoids; Diagnosis, Differential; Head
PubMed: 36169792
DOI: 10.1007/s12105-022-01482-1 -
The Malaysian Journal of Pathology Apr 2022The ameloblastoma is the most challenging odontogenic neoplasm to treat because of its locallyinvasive behaviour, severe clinical implication, risk of malignant...
The ameloblastoma is the most challenging odontogenic neoplasm to treat because of its locallyinvasive behaviour, severe clinical implication, risk of malignant transformation and high recurrence rate. Recent evidence suggests that BRAF, EGFR and CD10 have a role in the local invasiveness of ameloblastoma. However, the spatial distribution characteristics of these pro-invasive factors and their association with clinical parameters in this neoplasm are largely unexplored. We sought to address these issues in ameloblastoma subtypes and to determine their biological relevance. Nineteen unicystic (UA) and 20 conventional ameloblastoma (SMA) were subjected to immunohistochemical staining for BRAF, EGFR and CD10, and semiquantitative analysis was performed. All ameloblastoma cases (n=39/39; 100%) exhibited a BRAF+/EGFR+/CD10+immunoprofile. Their expression rates were significantly higher in SMA than UA (P<0.05). BRAF, essential for the progression and proliferation of ameloblastoma, was detected mainly in the cytoplasm of stellate reticulum-like>stromal>preameloblast- like cells (P<0.05). EGFR, a potent oncogenic protein, showed predominantly nuclear localisation. CD10, an apoptosis-inhibitory factor, was strongly expressed in the membrane of stellate reticulum-like cells. Taken together, present results suggest that the spatial distribution patterns of BRAF, EGFR and CD10 parallel the specific behaviours of SMA and UA. Their cellular and intracellular protein localisations have important targeted therapy implications.
Topics: Ameloblastoma; ErbB Receptors; Humans; Neprilysin; Odontogenic Tumors; Proto-Oncogene Proteins B-raf
PubMed: 35484883
DOI: No ID Found -
Asian Pacific Journal of Cancer... Nov 2022Ameloblastoma is regarded as the second most prevalent odontogenic tumor in the light of its prevalence, clinical characteristics, greater incidence of tumor recurrence,... (Meta-Analysis)
Meta-Analysis
INTRODUCTION
Ameloblastoma is regarded as the second most prevalent odontogenic tumor in the light of its prevalence, clinical characteristics, greater incidence of tumor recurrence, and therapeutic challenges. The aim of this systematic review was to establish the prevalence of ameloblastoma in the Indian subcontinent and to establish a national epidemiologic profile for these lesions.
MATERIAL AND METHODS
A systematic review was undertaken based on the PRISMA guidelines in search of epidemiologic studies concerning odontogenic tumors and ameloblastoma that are listed by PubMed, EBSCO, and Google Scholar embracing the period from January 2010 to December 2021, to evaluate the prevalence rate in India. A total of 277 publications were retrieved, of which 27 articles were selected, based on the World Health Organization classification of odontogenic tumors.
RESULTS
The affected individuals were on average in the third decade of life, with a higher male predominance. The majority of the tumors were multilocular radiolucencies in the posterior mandible, with follicular and plexiform histopathological features. The most common type of malignant lesion is ameloblastic carcinoma. Over 60% of follicular ameloblastoma recurred more frequently than the other types of ameloblastoma.The random effect model shows overall point estimate of 4.83 with 95% confidence interval (4.44 -5.26).
CONCLUSION
The systematic study indicates a slight male predisposition to ameloblastoma, with a peak incidence in the third decade of life and the mandible as the preferred anatomical site. The solid/multicystic ameloblastoma is the most prevalent histopathologic pattern. More epidemiological research on the prevalence rate of ameloblastoma is required, particularly in India, in an effort to accurately determine the national epidemiological profile of ameloblastoma.
Topics: Male; Humans; Female; Ameloblastoma; Prevalence; India; Odontogenic Tumors; Genotype
PubMed: 36444570
DOI: 10.31557/APJCP.2022.23.11.3601 -
Journal of Cancer Research and... 2019Metastasizing ameloblastoma (MA) is a very rare odontogenic tumor with 2% of incidence rate. It exhibits benign histopathological features and malignant intrinsic... (Review)
Review
Metastasizing ameloblastoma (MA) is a very rare odontogenic tumor with 2% of incidence rate. It exhibits benign histopathological features and malignant intrinsic quality in the form of metastasis which makes it a little more than a pathological curiosity. Various molecular aspects related with malignant behavior have been discussed. Because of this, it provides a diagnostic challenge for clinicians and surgeons. It is an elusive lesion which should be more researched and studied so that definitive diagnostic features can be put forward. The objective of this paper is to review the molecular aspect involved in the pathogenesis of MA which will aid in differentiating non-MA from MA and thus helping in providing proper treatment at an early stage.
Topics: Ameloblastoma; Biomarkers, Tumor; Disease Management; Disease Susceptibility; Epithelial-Mesenchymal Transition; Humans; Neoplasm Metastasis; Neoplasm Staging; Tumor Microenvironment
PubMed: 31169204
DOI: 10.4103/jcrt.JCRT_268_17 -
Nigerian Journal of Clinical Practice Oct 2022Ameloblastoma is a benign epithelial odontogenic tumor with a tendency for recurrence. Some recurrent tumors could behave unpredictably with atypical microscopic changes.
CONTEXT
Ameloblastoma is a benign epithelial odontogenic tumor with a tendency for recurrence. Some recurrent tumors could behave unpredictably with atypical microscopic changes.
AIM
To study the clinicopathologic features and diagnoses of recurrent tumors of ameloblastoma.
SETTINGS AND DESIGN
This is a 5-year (2012-2017) retrospective study of 17 consecutive patients with recurrent tumors of ameloblastoma in a Teaching Hospital in Enugu.
METHODS AND MATERIAL
The relevant clinicopathologic information, histology slides, and blocks were retrieved and reviewed. Descriptive analysis was used to determine the frequency, tables for categorical variables, and a Chi-square test was used to determine the statistical significance.
RESULT
Recurrent tumors constituted 33.3% (17/51) of all confirmed diagnoses of ameloblastoma. The histopathologic diagnosis of the recurrent tumors includes conventional ameloblastoma 58.8% (10/17), unicystic ameloblastoma 5.9% (1/17), and ameloblastic carcinoma 35.3% (6/17). There was bilateral mandibular involvement in 60.0%, pain 58.8%, ulceration 29.4%, and matted lymph nodes 5.9%. Tumors with positive fluid aspirates 82.4% (14/17) yielded dark-brown fluids in 90.0% (9/10) of recurrent ameloblastomas and in 66.7% (2/3) of ameloblastic carcinomas.
CONCLUSION
There was a high recurrence rate of recurrent tumors of ameloblastoma demonstrated in the present study, with a malignant presentation in some cases.
Topics: Humans; Ameloblastoma; Retrospective Studies; Nigeria; Odontogenic Tumors; Hospitals, Teaching
PubMed: 36308255
DOI: 10.4103/njcp.njcp_82_22 -
Nigerian Journal of Clinical Practice Sep 2022Ameloblastoma is a benign epithelial odontogenic tumor with a tendency for recurrence. The recurrent tumors behave unpredictably with atypical microscopic changes and...
BACKGROUND
Ameloblastoma is a benign epithelial odontogenic tumor with a tendency for recurrence. The recurrent tumors behave unpredictably with atypical microscopic changes and likelihood of malignant transformation.
AIMS
To study the clinicopathologic features and diagnostic outcome of recurrent tumors of ameloblastoma in Enugu. This is a six-year (2012-2017) retrospective study of 17 consecutive patients with recurrent tumors of ameloblastoma in a Teaching Hospital in Nigeria.
MATERIALS AND METHODS
The relevant clinicopathologic information, histology slides, and blocks were retrieved and reviewed. Descriptive analysis was used to determine the frequency, tables for categorical variables, and a Chi-square test was used to determine the statistical significance.
RESULT
Recurrent tumors constituted 33.3% (17/51) of all confirmed diagnoses of ameloblastoma. The diagnostic outcome of the recurrent tumors was conventional ameloblastoma 58.8% (10), unicystic ameloblastoma 5.9% (1), and ameloblastic carcinoma 35.3% (6). There was bilateral mandibular extension in 60.0% (9), pain 58.8% (10), ulceration 29.4% (5), and matted lymph nodes 5.9% (1). Tumors with positive fluid aspirates 82.4% (14) yielded dark-brown fluids in 90.0% (9) of recurrent ameloblastomas and in 66.7% (2) of ameloblastic carcinomas. Atypical peripheral hyperplasia, nuclear hyperchromatism, and increased vascularization were commonly observed in benign recurrences. The frequency of recurrence is significantly associated with the biological behavior of ameloblastoma P = 0.03.
CONCLUSION
Recurrent tumors of ameloblastoma presented atypical features and malignant transformation.
Topics: Ameloblastoma; Humans; Nigeria; Odontogenic Tumors; Retrospective Studies
PubMed: 36149215
DOI: 10.4103/njcp.njcp_82_22