抑癌基因PTEN和FHIT在口腔鳞癌中的表达及其与cyclin D1的相关性

目的检测抑癌基因PTEN、FHIT在正常口腔粘膜上皮和口腔鳞癌(OSCC)中的表达情况，并探讨其与cyclin D1的关系。方法采用免疫组化SP法检测62例OSCC中FHIT、PTEN、cyclin D1蛋白表达的情况．以12例正常口腔粘膜作对照。结果在正常口腔粘膜中PTEN均为强阳性表达(12／12)，在OSCC中24．2％(15／62)表现为PTEN蛋白表达的缺乏或减少；而FHIT在正常口腔粘膜中也均为强阳性表达(12／12)．在OSCC中17．7％(11／62)表现为FHIT蛋白表达缺乏或减少；cyclin D1在正常口腔粘膜中91．7％(11／12)表现为阴性或弱阳性表达．在OSCC中53．2％(33／62)表现为阳性或强阳性表达；PTEN与FHIT均为阳性或强阳性表达时，37．8％(28／74)cyclin D1表现为阴性或弱阳性．其中11例为正常口腔粘膜(占正常组的91．7％)。结论PTEN、FHIT在OSCC的发生过程中起着一定的作用；PTEN／FHIT的表达与cyclin D1有关，提示PTEN、FHIT能够下调cvclin D1的表达。

Expressions of PTEN and FHIT in oral squamous cell carcinoma and their relations with cyclin D1]

OBJECTIVE: To study the expressions of PTEN, FHIT and cyclin D1 in normal oral mucosa and oral squamous cell carcinoma (OSCC), and analyze the relationship between PTEN/FHIT and cyclin D1. METHODS: Immunohistochemical staining with SP methods was used to detect the expression of PTEN, FHIT and cyclin D1 in OSCC tissues in 62 cases and normal oral mucosa in 12 cases. RESULTS: The positivity rates of PTEN and FHIT were both 100% (12/12) in the normal oral mucosa, while in 62 cases of OSCC, 24.2% (15/62) and 17.7% (11/62) were negative for (or with low expression of) PTEN and FHIT, respectively. In normal oral mucosa, 91.7% (11/12) cases had negative or low cyclin D1 expression, while 53.2% (33/62) of the OSCC cases were positive for cyclin D1 expression. In all the cases, when PTEN and FHIT were strongly expressed, 37.8% (28/74) of the cases had negative or low expression of cyclin D1, including 11 normal cases. CONCLUSION: The tumor suppressor genes PTEN and FHIT play a role in the pathogenesis of OSCC, and PTEN and FHIT can down-regulate the expression of cyclin D1.