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Adel K El-Naggar

Publications and source records attributed to Adel K El-Naggar.

3 recordsLinked to original sources

Paired analysis of primary adenoid cystic carcinoma and derived cell lines reveals a mesenchymal and stem-like shift associated with therapy resistance.

Adenoid cystic carcinoma (ACC) is a salivary gland malignancy characterized by slow but persistent growth, frequent local recurrence, and late metastatic progression. Patients with unresectable, recurrent, or metastatic disease have limited therapeutic options. Efforts to identify effective therapeutic targets have been hindered by the limited availability of well-characterized ACC models. In this study, we established 11 ACC cell lines and performed RNA sequencing of nine cell lines and their matched primary tumors to evaluate the preservation and evolution of molecular and lineage-associated characteristics during cell line establishment. Comparative transcriptomic analysis revealed reduced epithelial and luminal differentiation programs in the cell lines, accompanied by enrichment of myoepithelial, EMT-, and cancer stem cell-associated transcriptional programs. Digital deconvolution and single-sample gene set enrichment analysis supported enrichment of hybrid EMT/stem-like states during in vitro propagation, while comparison with publicly available primary-recurrent ACC data demonstrated partial preservation of recurrence-associated plasticity and invasion programs. Protein-level validation of representative epithelial, myoepithelial, EMT, and stemness markers supported the major transcriptomic changes. In addition, a cell line with a higher stemness signature showed reduced sensitivity to cisplatin. Together, these findings indicate that ACC cell line establishment is associated with transcriptional reprogramming and enrichment of plastic, EMT/stem-like states while retaining selected ACC lineage characteristics. These models provide experimentally tractable platforms for investigating ACC progression, therapeutic response, and mechanisms of treatment resistance.

Adenoid cystic carcinoma

Salivary duct carcinoma- contemporary nuts and bolts from pathologist perspective.

INTRODUCTION: Salivary gland carcinomas are highly heterogeneous malignancies that present a complex variety of histological features and distinct clinical behaviors, with salivary duct carcinoma (SDCa) as the most clinically severe and aggressive subtype. The standard of care for these patients is a combined approach of surgery followed by radiotherapy. The aggressive clinical course of SDCa is primarily driven by frequent disease recurrences and systemic spread. AREAS COVERED: The publication of WHO 5th Classification of Head and Neck tumors has sparked a surge in research targeting SDCa. Owing to the highly aggressive behavior of the tumor, most literature heavily emphasizes the molecular pathology of SDCa.A systematic literature search was conducted using the PubMed with the following search terms: salivary duct carcinoma AND pathology OR updates OR molecular OR signaling pathway OR gene expression OR mutation OR oncogene OR tumor suppressor OR DNA methylation OR tumor microenvironment. Results were limited to primary research articles in English language. EXPERT OPINION: This article outlines key advancements in SDCa morphology, molecular pathology, and targeted therapies. Patient management in precision oncology will be fundamentally transformed by the classification of new morphologic subtypes, the discovery of molecular biomarkers, and an enhanced comprehension of tumor microenvironment.

HER 2

NOTCH1 acts as a tumor suppressor that induces early differentiation in head and neck cancer.

Inactivating NOTCH1 mutations in head and neck squamous cell carcinoma (HNSCC) were described over a decade ago, suggesting a tumor suppressor function - unlike its oncogenic role in other tumors. Today, much debate persists regarding a putative oncogenic role in HNSCC as well, with reports that NOTCH1 signaling drives tumor growth and a cancer stem cell (CSC) phenotype. In this work, comprehensive experiments unequivocally demonstrate that NOTCH1 is a tumor suppressor in HNSCC regardless of mutation or activation status and that it reduces CSC frequency. We developed a signature of NOTCH1 activation showing the pathway is associated with very early differentiation, an altered tumor microenvironment, and better prognosis. Clarifying whether NOTCH1 occasionally functions as an oncogenic driver in HNSCC is crucial to prognosis and personalized therapy. The results presented unify the field, reconcile conflicting data, and provide critical insights into the biological and clinical significance of NOTCH1, with broader implications in other squamous carcinomas with NOTCH1 mutations.

Receptor, Notch1