Distribution of Cytokeratin 17 in the Parenchymal Elements of Rat’s Submandibular Glands Subjected to Fractionated Radiotherapy

Abstract

Objectives The aim of this research was to study the intensity of cytokeratin 17 (CK17) in the parenchymal elements of rat’s submandibular salivary glands subjected to fractionated radiotherapy regimen that used for treatment of head and neck malignancy. Materials and Methods Twenty male albino rats were divided into two equal groups (normal and irradiated). The irradiated group received a radiation dose of 5 Grays daily for 5 days using therapeutic X-ray beam. Six months later, submandibular gland was dissected out and prepared for both histological and immunohistochemical studies. Results Submandibular gland of irradiated group showed two different types of histological alterations. The first alteration showed severe gland atrophy replaced by either fibrous or fatty tissues. In some sections, the gland exhibited proliferating activity in the form of profuse amounts of mitotic figures. Immunohistochemical examination of control glands displayed a mild cytoplasmic expression of CK17 of duct cells as well as serous acini. The staining pattern was either diffused or concentrated at the basal part of the cell with negative expression at its apical part. Statistical Analysis Expression of CK17 in submandibular gland of irradiated group displayed a highly significant differences (P < 0.001) in both intercalated and striated ducts. Many serous acini displayed a highly significant differences (P < 0.001) whereas, mucous acini were negatively stained. Conclusions The intensity and diffusion of CK17 expression in our results foretell the pathological effect of radiotherapy on the intermediate filaments of salivary gland parenchyma that interfered with production and/or secretion of saliva leading to xerostomia.

Immunohistochemical Evaluation of the Pathological Effects of Diabetes Mellitus on the Major Salivary Glands of Albino Rats

“…Several authors agree with this finding that CK17 in salivary gland cells plays an important role in cell structure and the intensity of expression is closely related to the differentiation status of the parenchymal cells. 8,21,27 The different patterns of CK17 distribution are thought to be related to the functional activity of the gland where the diffuse pattern of staining indicates the nonsecretory state, while the decrease of CK17 in the luminal portion was associated with the active state of secretion leaving the area for exocytosis. The expression pattern of CK17 focused at the basal cell part may be associated with an increase in the tensile force of acinar cells facing myoepithelium resulting in an increased pressure capacity to drive saliva through the lumen into the duct system.…”

“…The animal mounts humeral immune response to this specific antigen and produce antibody specific to this epitope termed monoclonal antibody which can be isolated from the animal to be used in the intracellular expression of this antigen. 21 Cytokeratins constitute an important biomarker because they are stable, relatively resistant to hydrolysis, formalin-fixed, and paraffin-embedded. Also, cytokeratins show great fidelity in expression and are highly antigenic.…”

“…22 The distribution of cytokeratin 17 (CK17) in the normal PG parenchyma is associated with cells of the duct system, whereas serous acinar cells have little or no cytokeratin in their cytoplasm. 21 Our study aimed to determine the expression of CK17 within the parenchymal elements of major salivary glands of both normal and diabetic albino rats to provide more information about the effects of DM on salivary glands structure that led to xerostomia.…”

“…22 The distribution of cytokeratin 17 (CK17) in the normal PG parenchyma is associated with cells of the duct system, whereas serous acinar cells have little or no cytokeratin in their cytoplasm. 21…”

Cyberknife Radiosurgery for the Treatment of Head and Neck Cancer: A Systematic Review

“… 41 43 44 Despite the accessibility of fractionated radiotherapy, there is evidence that the vital structures may get affected like the salivary glands, leading to xerostomia and thereby affecting the quality of life postradiotherapy. 45 In such situations, stereotactic radiosurgery like Cyberknife is an invaluable treatment option and plays a vital role in tissue preservation. In dentistry, this feature plays a vital role in improving the potential for dental rehabilitation, improving the function and at the same time offering better quality of life.…”