O‐GlcNAcylation in oral squamous cell carcinoma. (30th January 2018)

• Record Type: Journal Article
• Authors: Kongkaew, Tassaporn; Aung, Win Pa Pa; Supanchart, Chayarop; Makeudom, Anupong; Langsa‐ard, Sarawat; Sastraruji, Thanapat; Chaiyarit, Ponlatham; Krisanaprakornkit, Suttichai
• Is Part Of: Journal of oral pathology & medicine. Volume 47:Number 3(2018)
• Page Start: 260
• Page End: 267
• Publication Date: 2018-01-30
• Subjects: Akt -- epidermal growth factor receptor -- O‐GlcNAc transferase -- O‐GlcNAcylation -- oral squamous cell carcinoma; Dentistry -- Periodicals; Teeth -- Diseases -- Periodicals; 617
• DOI: 10.1111/jop.12680
• Languages: English
• ISSNs: 0904-2512

Abstract

Abstract : Background: Two post‐translational mechanisms commonly demonstrated in various cancers are protein phosphorylation and glycosylation by O ‐linked β‐ N ‐acetylglucosamine ( O ‐GlcNAc). However, only phosphorylation of the epidermal growth factor receptor (EGFR)/Akt pathway has been reported in oral squamous cell carcinoma (OSCC). Therefore, we aimed to determine both post‐translational modifications in OSCC tissues and in oral cancer cells compared to normal tissues and oral keratinocytes and to find correlations of these modifications with histological grading. Methods: Thirty‐two OSCC and ten normal formalin‐fixed and paraffin‐embedded sections were probed with the anti‐ O ‐GlcNAc, anti‐ O ‐GlcNAc transferase (OGT), anti‐phosphorylated‐EGFR tyr1173, and anti‐phosphorylated‐Akt ser473 antibodies following standard immunohistochemistry. The immunohistochemical (IHC) score was determined using the Fromowitz standard. Whole cell lysates of oral cancer cells and normal oral keratinocytes were immunoblotted with the anti‐ O ‐GlcNAc antibody. Results: The median IHC scores of O ‐GlcNAc or OGT between OSCC and normal tissues were not different, whereas those of phosphorylated‐EGFR tyr1173 and phosphorylated‐Akt ser473 were significantly higher in OSCC than normal tissues ( P < .001 and P < .01, respectively). Similarly, expression of O ‐GlcNAcylated proteins in oral cancer cells and normal oral keratinocytes did not differ. In the OSCC group, the median IHC scores of O ‐GlcNAc and OGT were significantly lower than those of phosphorylated‐EGFR tyr1173 and phosphorylated‐Akt ser473 ( P < .01 and P < .001, respectively). The IHC scores of O ‐GlcNAc or OGT were not determined to correlate with histological grading. Conclusion: Unlike other types of cancers, our findings demonstrate that the levels of O ‐GlcNAcylation are not significantly increased in OSCC tissues or in oral cancer cells and are not associated with the histological grading of OSCC.