Exploiting salivary miR-375 as a clinical biomarker of oral potentially malignant disorder

Hsi-Feng Tu; Li-Han Lin; Kuo-Wei Chang; Hui-Wen Cheng; Chung-Ji Liu

doi:10.1016/j.jds.2021.09.020

Exploiting salivary miR-375 as a clinical biomarker of oral potentially malignant disorder

J Dent Sci. 2022 Apr;17(2):659-665. doi: 10.1016/j.jds.2021.09.020. Epub 2021 Sep 20.

Authors

Hsi-Feng Tu^{1

2

3}, Li-Han Lin⁴, Kuo-Wei Chang^{2

3}, Hui-Wen Cheng⁴, Chung-Ji Liu^{2

3

5}

Affiliations

¹ Department of Dentistry, National Yang Ming Chiao Tung Hospital, Yi-Lan, Taiwan.
² Department of Dentistry, College of Dentistry, National Yang Ming Chiao Tung University, Taipei, Taiwan.
³ Institute of Oral Biology, College of Dentistry, National Yang Ming Chiao Tung University, Taipei, Taiwan.
⁴ Department of Medical Research, Mackay Memorial Hospital, Taipei, Taiwan.
⁵ Department of Oral and Maxillofacial Surgery, MacKay Memorial Hospital, Taipei, Taiwan.

Abstract

Background/purpose: Oral potentially malignant disorder (OPMD) is an important premalignancy worldwide. MicroRNAs (miRNAs) are endogenously expressed non-coding RNAs that regulate the post-transcriptional levels of targeted mRNAs. MiRNA-375 (miR-375) is markedly downregulated in oral carcinoma tissues and plays an oncogenic role in oral carcinogenesis. We explored the potential of the deregulated salivary miR-375 levels in OPMD patients.

Materials and methods: . We analyzed the levels of miR-375 in the saliva of patients with OPMD (n = 45) and healthy controls (n = 24) by quantitative RT-PCR. The cell lysates and supernatants were treated with the miR-375 mimic and inhibitor.

Results: Salivary miR-375 levels were decreased markedly in the patients with OPMD, compared with the controls. OPMD patients with non-dysplasia showed a higher abundance of miR-375 in the saliva than dysplasia patients, suggesting that salivary miR-375 is a more sensitive marker for OPMD. Patients with malignant transformation during the follow-up period showed lower expression of saliva miR-375 than the others. MiR-375 expression was markedly decreased by treatment with the miR-375 inhibitor, and the supernatants of both NHOK and SAS cells showed a corresponding decline in miR-375 expression.

Conclusion: Our results indicate the potential application of salivary miR-375 as a biomarker for the detection and long-term follow-up of OPMD.

Keywords: Biomarker; OPMD; Oral epithelial dysplasia; Saliva; miR-375.