Spleen tyrosine kinase as a novel candidate tumor suppressor gene for human oral squamous cell carcinoma

• DOI: 10.1002/ijc.24237
• Publication Date: 2008-12-24T22:51:53Z
• Authors: Satoru Ogane; Takeshi Onda; Nobuo Takano; Tetsuo Yajima; Takeshi Uchiyama; Takahiko Shibahara
• Keywords: Adult; Male; Intracellular Signaling Peptides and Proteins; DNA Methylation; Middle Aged; Protein-Tyrosine Kinases; Immunohistochemistry; 3. Good health; 03 medical and health sciences; 0302 clinical medicine; Cell Line, Tumor; Mutation; Carcinoma, Squamous Cell; Humans; Syk Kinase; Female; Genes, Tumor Suppressor; Mouth Neoplasms; Aged

We analyzed the mutational and methylation status of spleen tyrosine kinase (Syk) gene both mRNA protein levels in primary oral squamous cell carcinoma (OSCC) OSCC-derived lines examined function Syk vitro. Using quantitative real-time reverse transcription polymerase chain reaction, Western blotting immunofluorescence on 7 normal keratinocytes (NOKs), expression were commonly downregulated all compared to NOKs. Although no sequence variation coding region was identified these lines, we found frequent hypermethylation CpG island region. restored by experimental demethylation. In addition, using a wound healing assay vitro invasion assay, performed functional analysis transfected into they showed significant inhibition motility invasiveness. clinical samples, high frequencies downregulation detected immunohistochemistry (33 53 [62%]). Furthermore, correlated significantly (p = 0.047) with tumor metastasis cervical lymph nodes. These results suggest that is frequently inactivated during carcinogenesis an epigenetic mechanism may regulate loss possibly leading metastasis.