Author(s)

Kurara Yoshimura¹, Naomi Yada², Kou Matsuo², Hisako Hikiji³, Daigo Yoshiga¹, Manabu Habu¹, Masaaki Sasaguri¹, Kazuhiro Tominaga¹

¹Department of Science of Physical Functions, Division of Oral and Maxillofacial Surgery, Kyushu Dental University, Kitakyushu, Japan.
²Department of Health Promotion, Division of Oral Pathology, Kyushu Dental University, Kitakyushu, Japan.
³School of Oral Health Sciences, Kyushu Dental University, Kitakyushu, Kitakyushu, Japan.

Oral lichen planus (OLP) is a disease of unknown etiology affecting oral mucosa by mediated chronic inflammation and is classified as a potentially malignant oral disorder. SOCS1 and SOCS3 in the SOCS family have been identified as negative regulators of the cytokine-activated JAK/STAT pathway responsible for inflammatory reaction. The DNA methylation in the promoter regions of SOCS1 and SOCS3 have been reported to correlate with carcinogenesis. In this study, we performed methylation-specific PCR (MSP) to investigate the methylation status of the promoter regions in SOCS1 and SOCS3 genes using biopsy samples from OLP and oral squamous cell carcinoma (OSCC) patients. SOCS1 was methylated in 14/29 (48.3%) cases with OLP and 7/15 (46.7%) cases with OSCC. At the same time, SOCS3 was methylated in 25/29 (86.2%) cases with OLP and 11/15 (73.3%) cases with OSCC. We didn’t recognize any DNA methylation in SOCS1 or SOCS3 genes from the exfoliated cytological specimens of normal buccal mucosa. Furthermore, mRNA expression level was analyzed using real-time RT-PCR method to evaluate the correlation with DNA methylation status. DNA methylation status of SOCS1 seemed not to affect the expression level of SOCS1 mRNA. At the same time, DNA methylation status of SOCS3 was negatively correlated with the expression level of SOCS3 mRNA (p < 0.05). We posit frequent methylation of the SOCS3 gene promoter, theoretically resulting in the increase of cytokines expression, might be associated with the etiological mechanism of OLP.

Oral Lichen Planus, SOCS3, SOCS1, Methylation

Yoshimura, K. , Yada, N. , Matsuo, K. , Hikiji, H. , Yoshiga, D. , Habu, M. , Sasaguri, M. and Tominaga, K. (2018) Methylation and Expression Status of SOCS1 and SOCS3 in Oral Lichen Planus. Open Journal of Stomatology, 8, 168-181. doi: 10.4236/ojst.2018.85016.