Abstract:

Abstract:Objective To explore the expressions of STAT3 mRNA and STAT3 protein and study their correlations with the occurrence,development,invasion,and metastasis of oral squamous cell carcinoma (OSCC). Methods In situ hybridization (ISH) and immunohistochemistry were used to detect the expressions of STAT3 mRNA and STAT3 protein  in 60 cases of normal oral mucosa,30 cases of atypical hyperplasia and 60 patients with oral squamous cell carcinoma,at the same time the clinical information was combinated for analysis. Results The positive expression rates of STAT3 mRNA  in normal mucosa,atpical hyperplasia and oral squamous cell carcinoma  were 25.0% (15/60),40.0% (12/30),68.3% (41/60),respectively;there were  significant differences between various groups (χ2 = 23.855,P<0.05). The STAT3 mRNA expressions between different differentiation,different depths of invasion and lymph node metastasis in oral squamous cell carcinoma had significant differences (χ2=15.912，χ2=25.616，χ2=7.455，P<0.05）. The STAT3 protein expression rates were dramaticlly different at different grades of cancer (grade Ⅰ 40.0%,gradeⅡ 73.9%,grade Ⅲ 90.9%;χ2=11.532， P<0.05).The STAT3 protein expression rate was significantly different between shallow infiltraion cancer and deep infiltration cancer（26.3% vs 92.7%，χ2=24.989，P<0.05）. The STAT3 protein expression rate was also dramaticlly different between  lymph node metastasis cancer and non-lymph node metastasis cancer (91.3% vs 59.5%，χ2=5.602，P<0.05）.The STAT3 protein expression rates in normal mucosal tissues,atypical hyperplasia and cancer rates were  13.3% (8/60),30.0% (9/30),and 71.2% (43/60),respectively;the differences between various groups were　significant (χ2 = 23.855,P<0.05).The STAT3 protein expression was closely related with　  cancer tissue differentiation,depth of invasion and lymph node metastasis  (χ2 = 11.532,χ2 = 24.989,χ2 = 5.602,P<0.05). Conclusion The STAT3 mRNA and protein are over-expressed in oral squamous cell carcinoma tissue and have close correlations with biological behavior,occurrence and development of oral squamous cell carcinoma . STAT3 may be a new assistant indicator for early diagnosis and prognosis judgement of oral squamous cell carcinoma.

Key words: STAT3;oral squamous cell carcinoma;in situ hybridization;immunohistochemistry