Signal transducer and activators of transcription 3 regulates cryptotanshinone‑induced apoptosis in human mucoepidermoid carcinoma cells

Abstract

Background: Cryptotanshinone (CT) is a biologically active compound from the root of Salvia miltiorrhiza that has been reported to induce apoptosis in various cancer cell lines; but, it has not yet been fully explored in human mucoepidermoid carcinoma (MEC).Objective: Here, we demonstrated the apoptotic effects and its related mechanism in MC‑3 and YD‑15 human MEC cell lines.Materials and Methods: The effects of CT on apoptotic activity were evaluated by cell proliferation assay, Western blotting, 4’‑6‑diamidino‑2‑phenylindole staining, reverse transcription‑polymerase chain reaction, and luciferase assay.Results: Our data show that CT treatment of MC‑3 cells results in anti‑proliferative and apoptotic activities in MC‑3 and it is accompanied by a decrease in phosphorylation and dimerization of signal transducer and activators of transcription 3 (STAT3). CT decreased the expression levels of myeloid cell leukemia‑1 (Mcl‑1) and surviving, whereas Bcl‑xL expression was not changed. CT clearly regulates survivin protein at a transcriptional level and alters Mcl‑1 through proteasome‑dependent protein degradation. In addition, CT‑induced apoptotic cell death in YD‑15, another human MEC cell line, was associated with the inhibition of STAT3 phosphorylation.Conclusion: These data suggest that CT could be a good apoptotic inducer through modification of STAT3 signaling in human MEC cell lines.

Keywords: Apoptosis; cryptotanshinone; myeloid cell leukemia‑1; mucoepidermoid carcinoma; signal transducer and activator of transcription 3; survivin