Expression and promoter methylation of Wnt inhibitory factor-1 in the development of oral submucous fibrosis.
Oral squamous cell carcinoma (OSCC) is a type of head and neck malignancy with a high mortality rate. Oral submucous fibrosis (OSF) is the pre-cancerous lesion of OSCC, whose molecular mechanisms in OSCC tumorigenesis remain largely unclear. Activation of the Wnt/β-catenin signaling pathway plays an important role in oral mucous carcinogenesis, although rare mutations of Wnt signaling molecules are found in OSCC, suggesting an epigenetic mechanism mediating aberrant Wnt/β‑catenin signaling in OSCC. Wnt inhibitory factor-1 (WIF1) is an Wnt antagonist, and its downregulation and methylation have been reported in a number of malignancies. However, the expression and methylation of WIF1 in the development of OSF have yet to be reported. In the present study, we investigated the WIF1 expression level by immuno-histochemical staining and semi‑quantitative RT-PCR in normal oral, OSF and OSCC tissues, as well as the methylation status by methylation-specific PCR and bisulfite genomic sequencing. The results showed that WIF1 was readily expressed in normal oral mucous tissues, but decreased gradually in OSF early, moderately advanced and advanced tissues, and was less expressed in OSCC tissues. Moreover, WIF1 was able to translocate from the nuclear to cytoplasm in OSF and OSCC tissues. Furthermore, WIF1 was frequently methylated in OSCC cases with betel quid chewing habit, but not in normal oral mucous and different stages of OSF tissues, suggesting WIF1 methylation is tumor-specific in the development of OSF. Thus, the results demonstrated that WIF1 is frequently downregulated or silenced by promoter methylation in the carcinogenesis of OSF, which serves as a potential epigenetic biomarker for the early detection of OSCC.
Department of Oral and Maxillofacial-Head and Neck Oncology, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200011, P.R. China.
Shanghui
S
Zhou
Molecular Oncology and Epigenetics Laboratory, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China.
Ling
L
Chen
Department of Oral and Maxillofacial-Head and Neck Oncology, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200011, P.R. China.
Mubarak
M
Mashrah
Department of Oral and Maxillofacial-Head and Neck Oncology, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200011, P.R. China.
Yun
Y
Zhu
Department of Oral and Maxillofacial Surgery, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China.
Zhijing
Z
He
Department of Oral Pathology, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200011, P.R. China.
Yuhua
Y
Hu
Molecular Oncology and Epigenetics Laboratory, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China.
Tingxiu
T
Xiang
Department of Oral Pathology, Xiangya Stomatological Hospital, Central South University, Changsha, Hunan 410078, P.R. China.
Zhigang
Z
Yao
Department of Oral and Maxillofacial Surgery, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China.
Feng
F
Guo
Department of Oral and Maxillofacial-Head and Neck Oncology, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200011, P.R. China.
Chenping
C
Zhang
D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics* / Q000378:metabolism; D002294:Carcinoma, Squamous Cell / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D002467:Cell Nucleus / Q000235:genetics / Q000378:metabolism; D002681:China; D003593:Cytoplasm / Q000235:genetics / Q000378:metabolism; D019175:DNA Methylation; D044127:Epigenesis, Genetic; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D008297:Male; D009062:Mouth Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D009914:Oral Submucous Fibrosis / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D011401:Promoter Regions, Genetic; D012097:Repressor Proteins / Q000235:genetics* / Q000378:metabolism; D017422:Sequence Analysis, DNA / Q000379:methods
D048868:Adaptor Proteins, Signal Transducing; D012097:Repressor Proteins; C485569:WIF1 protein, human