Introduction: Heat Shock Protein 60 (Hsp60) is a member of the chaperoning system that assists protein folding inside mitochondria and playsother roles beyond these organelles. It is implicated in the carcinogenic processes in various types of cancer. In human salivary glands, Hsp60 hasnot yet been measured or mapped in detail and its role in gland development and functioning is virtually unknown. Consequently, its potential asbiomarker for gland diseases, including malignancies cannot be assessed. The S-100 protein, a known marker for schwannomas, has been foundalso in myoepithelial-cell carcinomas of the salivary glands. Here, we present our initial findings on the anatomic-histological distribution of Hsp60in human submandibular salivary gland (SMG) at various stages of development and its changes during tumorigenesis, in parallel with changes ofS-100 in salivary gland tumors.Methods: Adult human submandibular gland (normal and tumoral) and embryonic head tissue samples were processed by standard methods forroutine histological analysis. Additionally, these same sections underwent immunohistochemical staining using antibodies against Hsp60 and S-100. Specimens from patients were obtained from the archives of the Human Pathology Section, Department of Health Science, University ofPalermo, Italy. All procedures were in accordance with the Helsinki Declaration. We determined the percentages of cells immunopositive forHsp60 or S-100 and made comparative evaluations applying the one way ANOVA.Results: Hsp60 was present in the acini and ducts of embryonic salivary glands but had a different distribution pattern in adult glands: it occurredonly in the ducts and in a few acini. In contrast, Hsp60 was not detected in Pleomorphic Adenoma (PA) or Warthin’s tumor (WT) , whereas itslevels were high in Adenoid Cystic Adenoma (ACC) . S-100 was present in the nuclei and/or in the cytoplasm in PA and ACC and its levels in thenuclei in ACC were higher than in the PA nuclei .Conclusions: Since the chaperonin is abundant in acini and ducts of embryonic salivary glands, it can be hypothesized that it actively participatesin the developmental process leading to the formation of a wholly functional adult, mature organ. Hsp60 and S-100 immunopositivities were highin the malignant tumor implying their involvement in neoplasm formation and progression. These results foreshadow the diagnostic andprognostic potential of Hsp60 and S-100 when measured side by side as biomarkers useful for distinguishing between benign and malignanttumors.
|Number of pages||1|
|Publication status||Published - 2019|