Expression of oncostatin M in chronic obstructive sialadenitis of the submandibular gland

Abstract

Objectives: We investigated the expression of oncostatin M messenger RNA (mRNA) and protein in normal submandibular glands and those with chronic obstructive sialadenitis and localized the expression of oncostatin M protein. Methods: Submandibular glands from 10 patients with chronic obstructive sialadenitis as a study group and 10 normal submandibular glands as a control group were examined. Oncostatin M mRNA extracted from submandibular gland was used for reverse transcription-polymerase chain reaction and analyzed semiquantitatively. The difference in expression level of oncostatin M protein between the 2 groups was analyzed through Western blot analysis, and oncostatin M protein was localized immunohistochemically. Results: The expression levels of oncostatin M mRNA and protein were significantly increased in the study group. The protein was predominantly localized in ductal epithelia and infiltrating inflammatory cells and was more strongly expressed in the study group also. Conclusions: Oncostatin M is expressed in both chronic obstructive sialadenitis and normal submandibular gland, and is up-regulated in chronic obstructive sialadenitis. These results suggest that oncostatin M is involved in the pathologic process of chronic obstructive sialadenitis. However, the physiologic role in normal glands, as well as a possible role in the development of chronic obstructive sialadenitis, remains to be elucidated.