RESUMEN
Head and neck squamous cell carcinomas (HNSCCs) are aggressive, recurrent, and metastatic neoplasms with a high occurrence around the world and can lead to death when not treated appropriately. Several molecules and signaling pathways are involved in the malignant conversion process. Epithelial-mesenchymal transition (EMT) has been described in HNSCCs, a major type of aggressive carcinoma. EMT describes the development of epithelial cells into mesenchymal cells, which depends on several molecular interactions and signaling pathways that facilitate mesenchymal conversion. This is related to interactions with the microenvironment of the tumor, hypoxia, growth factors, matrix metalloproteinases, and the presence of viral infections. In this review, we focus on the main molecules related to EMT, their interactions with the tumor microenvironment, plasticity phenomena, epigenetic regulation, hypoxia, inflammation, their relationship with immune cells, and the inhibition of EMT in the context of HNSCCs.
RESUMEN
BACKGROUND: Ameloblastomas are common benign epithelial odontogenic neoplasms that present an aggressive and unpredictable behavior that may modify treatment strategies. Different signaling pathways that participate in the progression of these tumors have been identified. B-raf proto-oncogene serine/threonine kinase (BRAF) is a protein involved in the behavior of ameloblastomas, and it is related to many cell mechanisms. BRAF gene mutations have been identified in ameloblastomas, of which the BRAF V600E (valine substituted by glutamic acid at amino acid 600) mutation has been the most common and can be present concomitantly with other mutations that may be involved in its behavior. Targeted therapies have been used as an alternative in the case of resistance or contraindications to conventional treatments. AIM: To document the presence of BRAF V600E and additional mutations, their behavior, and targeted therapies in these tumors. METHODS: An electronic literature search was conducted according to PRISMA guidelines in PubMed/MEDLINE, Cochrane, EMBASE, and SpringerLink using the terms "ameloblastomas", "BRAF V600E", "additional mutations", and "targeted therapies". Ameloblastomas were classified according to WHO guidelines. Inclusion criteria were articles in English, published not more than 10 years ago, and studies with laboratory works related to BRAF V600E. Articles were evaluated by two independent reviewers and retrieved for full-text evaluation. The EBLIP Critical Appraisal Checklist was used to evaluate the quality of the eligible studies. Descriptive statistical analysis was performed. RESULTS: Two independent reviewers, with a substantial concordance indicated by a kappa coefficient of k = 0.76, evaluated a total of 19 articles that were included in this study. The analysis registered 521 conventional ameloblastomas (AM), 81 unicystic ameloblastomas (UA), 13 ameloblastic carcinomas (AC), three metastatic ameloblastomas (MA), and six peripheral ameloblastomas (PA), of which the histopathological type, anatomic location, laboratory tests, expression of BRAF mutation, and additional mutations were registered. The BRAF V600E mutation was found in 297 AM (57%), 63 UA (77.7%), 3 AC (23%), 1 MA (50%), and 5 PA (83.3%). Follicular type predominated with a total of 116 cases (40%), followed by plexiform type with 63 cases (22.1%). Furthermore, both types presented additional mutations, in which alterations in JAK3 P132T, SMARCB1, PIK3CA, CTNNB1, SMO, and BRAF G606E genes were found. Four case reports were found with targeted therapy to BRAF V600E. CONCLUSION: The identification of BRAF V600E and additional mutations as an aid in targeted therapies has been a breakthrough in alternative treatments of ameloblastomas where surgical treatments are contraindicated.
RESUMEN
En la actualidad, a nivel mundial, el carcinoma oral de células escamosas (COCE) es el tumor maligno de aparición más común de la región, el cual representa la sexta entidad principal de cáncer por incidencia, con la aparición de más de 300 000 casos anuales y alrededor de 150 000 muertes.El COCE se caracteriza por su agresividad, alta recurrencia y metástasis linfática y hematógena, además de resistencia al tratamiento y un bajo índice de supervivencia a los 5 años. Un factor que ejerce amplia influencia en la progresión de las células tumorales y el mal pronóstico es el fenómeno de transición epitelial mesenquimal (TEM), el cual se define como la adquisición de características estromales de una célula epitelial, perdiendo su capacidad adhesiva, lo que le permite adoptar un comportamiento agresivo e invasivo.
En la actualidad, a nivel mundial, el carcinoma oral de células escamosas (COCE) es el tumor maligno de aparición más común de la región, el cual representa la sexta entidad principal de cáncer por incidencia, con la aparición de más de 300 000 casos anuales y alrededor de 150 000 muertes.El COCE se caracteriza por su agresividad, alta recurrencia y metástasis linfática y hematógena, además de resistencia al tratamiento y un bajo índice de supervivencia a los 5 años. Un factor que ejerce amplia influencia en la progresión de las células tumorales y el mal pronóstico es el fenómeno de transición epitelial mesenquimal (TEM), el cual se define como la adquisición de características estromales de una célula epitelial, perdiendo su capacidad adhesiva, lo que le permite adoptar un comportamiento agresivo e invasivo.
RESUMEN
This manuscript provides an update to the literature on molecules with roles in tumor resistance therapy in head and neck squamous cell carcinoma (HNSCC). Although significant improvements have been made in the treatment for head and neck squamous cell carcinoma, physicians face yet another challenge-that of preserving oral functions, which involves the use of multidisciplinary therapies, such as multiple chemotherapies (CT) and radiotherapy (RT). Designing personalized therapeutic options requires the study of genes involved in drug resistance. This review provides an overview of the molecules that have been linked to resistance to chemotherapy in HNSCC, including the family of ATP-binding cassette transporters (ABCs), nucleotide excision repair/base excision repair (NER/BER) enzymatic complexes (which act on nonspecific DNA lesions generated by gamma and ultraviolet radiation by cross-linking and forming intra/interchain chemical adducts), cisplatin (a chemotherapeutic agent that causes DNA damage and induces apoptosis, which is a paradox because its effectiveness is based on the integrity of the genes involved in apoptotic signaling pathways), and cetuximab, including a discussion of the genes involved in the cell cycle and the proliferation of possible markers that confer resistance to cetuximab.