Calretinin is expressed in the stroma of adamantinomatous craniopharyngioma and may induce calcification

• Calretinin was expressed in the stroma of ACP tissues.
• Calretinin of expression correlates with calcification degree of ACP.
• Calretinin may play a role in calcification of ACP.

ObjectivesCalretinin is expressed in many tumors. However, the role of calretinin in craniopharyngiomas (CPs) remains unknown.Patients and methodsThe study included 77 adamantinomatous CP (ACP). ACP calcification was divided into several categories on the basis of the incidence and extent of the calcium deposits evident on computed tomography (CT) images. The presence and expression pattern of calretinin were investigated using immunohistochemistry and western blotting. CP cell culture and small interfering (si)RNA of calretinin transfection was also carried out to clarify the role of calretinin in ACP calcification.Results61 cases exhibited calcification on CT, and 63 samples were immunopositive to calretinin. The western blotting results were consistent with the immunohistochemical findings. Calretinin expressions differed significantly among ACP groups basing on calcification degree, and a positive correlation was observed between calretinin expression and calcification degree (r = 0.853, P < 0.001). Calretinin siRNA transfection further demonstrated the role calretinin played in ACP calcification.ConclusionsCalretinin is expressed in the tumor stoma of calcified ACP, and its expression correlated with calcification degree. Drugs that target calretinin to reduce calcification and improve the postoperative function of ACP patients should be further researched.