Differential Expression of Mucin in Salivary Gland Tumours.

Background and Objectives: Mucin has been implicated via various mechanisms in the development and growth of tumour cells. However, mucin expression studies in salivary gland tumours are limited, especially with samples from minor salivary glands. This study aims to investigate and compare mucin expression in benign and malignant salivary gland tumours of minor and major salivary gland origins. Materials and Methods: Special stains were used to stain neutral mucin (Periodic acid Schiff), sialomucin (Alcian Blue) and sulfomucin (Aldehyde Fuschin) within tissues from six normal salivary glands and 73 salivary gland tumours including 31 pleomorphic adenomas, 27 mucoepidermoid carcinomas, and 15 adenoid cystic carcinomas. A semi-quantitative approach was used to evaluate mucin expression within ductal lumens. Sialomucin was the most expressed mucin in all salivary gland tumours, regardless of origin. Results: A significant difference was observed in the mucin expression between benign and malignant salivary gland tumours, as pleomorphic adenoma showed three times significantly higher expression of sialomucin compared to mucoepidermoid carcinoma and adenoid cystic carcinoma (p = 0.028). Pleomorphic adenomas of major glands showed 42 times significantly higher expression of sialomucin compared to those of minor glands (p = 0.000). Conclusions: Sialomucin content in pleomorphic adenomas of major glands was vastly increased compared to that in minor glands. Differential sialomucin expression in benign and malignant salivary gland tumours suggests a role in diagnosing of borderline salivary gland tumours.

Histological characterization of pulp regeneration using decellularized human dental pulp and mesenchymal stem cells in a feline model.

Regenerative endodontics aims to restore pulp tissues, thus preserving the vitality of the tooth. One promising approach involves the utilization of decellularized human dental pulp (DHDP) as a scaffold repopulated with Wharton's Jelly mesenchymal stem cells (WJMSCs). This study aimed to regenerate pulp tissues using DHDP and WJMSCs following pulpectomy in mature canine teeth of a feline animal model and to investigate the histological features of the regenerated pulp. A 12-month-old male domestic shorthaired felines were used as subjects. Teeth were categorized into untreated (Group 1), pulpectomy with mineral trioxide aggregate (MTA) (Group 2), and pulpectomy with DHDP-repopulated scaffold and MTA (Group 3). The animals were sacrificed six weeks post-intervention. H&E and immunohistochemistry using anti-collagen type 1 and laminin antibodies were used to stain the tissue sections. Histological examinations presented pulp-like tissues in Group 3, with tissue components similar to the structures found in Group 1. Immunohistochemical analysis demonstrated the presence of collagen type I and laminin within the regenerated tissues. The root canals of teeth in Group 2 were devoid of pulpal tissue. DHDP with WJMSCs can potentially be used for pulp regeneration, supporting the modality for developing new clinical protocols in stem cell therapy.

Do Clear Cell Changes in Oral Squamous Cell Carcinoma Warrant It Being Recognised as a Variant?

Histological variants of oral squamous cell carcinoma (OSCC) include verrucous, basaloid, spindle cell, adenosquamous, papillary, and acantholytic types. Clear-cell changes in OSCC are rare. We report a case of a 65-year-old male Chinese patient who presented with a swelling in the lower-left mandible for three weeks, causing ill-fitting of his lower denture and an ulcer on the floor of the mouth. Histologically, the lesion showed a dense proliferation of malignant tumor cells arranged in islands and sheets consisting of squamoid cells intermixed with signet ring-shaped clear cells. The clear cells were negative for mucicarmine, periodic acid Schiff (PAS), periodic acid Schiff-diastase (PAS-D), and alcian blue (AB). Immunohistochemistry showed the tumor cells were immuno-positive for cytokeratin (CK) and p63, but CK7, CK20, and S100 were immuno-negative. Therefore, a metastatic tumor in the oral cavity was suggested. However, the CT scan did not show any primary tumors in other sites. Histopathologically, the surgical specimen showed signet-ring-shaped clear cells in the stroma with squamoid cells invading the underlying connective tissue from the surface epithelium, suggesting a diagnosis of clear cell changes in OSCC. Follow-up showed recurrent OSCC at the base of the tongue with lymph node metastasis and distant metastasis in the lung. Only a few cases of clear-cell changes have been reported, with most having a poor prognosis. This case report adds one more case of clear cell changes in the OSCC with a poor prognosis. We reviewed the literature to understand their clinical behavior. Due to the rarity of its (clear cell changes) occurrence, further research is required in order to obtain a better understanding of the clinical behavior and prognosis of these clear cell changes seen in OSCC.

Therapeutic Potential of Polyphenol and Nanoparticles Mediated Delivery in Periodontal Inflammation: A Review of Current Trends and Future Perspectives.

Periodontitis is an oral inflammatory process involving the periodontium, which is mainly caused by the invasion of periodontopathogenic microorganisms that results in gingival connective tissue and alveolar bone destruction. Metabolic products of the oral pathogens and the associated host immune and inflammatory responses triggered are responsible for the local tissue destruction. Numerous studies in the past decades have demonstrated that natural polyphenols are capable of modulating the host inflammatory responses by targeting multiple inflammatory components. The proposed mechanism by which polyphenolic compounds exert their great potential is by regulating the immune cell, proinflammatory cytokines synthesis and gene expression. However, due to its low absorption and bioavailability, the beneficial effects of these substances are very limited and it hampers their use as a therapeutic agent. To address these limitations, targeted delivery systems by nanoencapsulation techniques have been explored in recent years. Nanoencapsulation of polyphenolic compounds with different carriers is an efficient and promising approach to boost their bioavailability, increase the efficiency and reduce the degradability of natural polyphenols. In this review, we focus on the effects of different polyphenolic substances in periodontal inflammation and to explore the pharmaceutical significance of polyphenol-loaded nanoparticles in controlling periodontitis, which may be useful for further enhancement of their efficacy as therapeutic agents for periodontal disease.