The Significance And Relationships Between PTEN,P27 And CyclinD1 Expressions In Oral Squamous Cell Carcinoma

Objective :To study the localization and expression lever of PTEN,a tumor suppressor gene .And their relationship to p27 protein and cyclinD1 which are presumed downstream targets of PTEN,and clinical pathologic factors as well as the prognostic factors in 54 oral squamous cell carcinoma patients. Methods : The expression of PTEN ,p27,cyclinD1,was examined by immunohistochemistry S-P method in 14 cases of oral mucosa ,11cases of oral epithelial dysplasia and 54 of cases oral squamous cell carcinoma(OSCC). Results wese compared with clinical pathologic parameters ,and p27and cyclinD1 protein expression which were evaluated by immunohistochemical methods ,too.Results: 1. PTEN showed cytoplasm staining .Normal oral mucosa tissues was all positivefor PTEN protein . In the tissues from oral epithelial dysplasia ,90.9 % were positive for PTEN protein . In the tissues from OSCC ,75.9 % were positive for PTEN protein, there was no significant difference in the expression of PTEN in precancerous lesions (p>0.05).But ,there was significant difference in the expression of PTEN in cases of oral normal mucosa and oral squamous cell carcinoma .PTEN oncoprotein positive staining was found in 82.3% of well differentiared tumors,41.7%of moderately differentiated tumors and 14.3% of poorly differentiated tumors. PTEN oncoprotein positive staining was found in 83.3% of nolymph node metastasis, PTEN oncoprotein positive staining was found in 41.7% of lymph node metastasis. PTEN protein expression did not show correlation to sex and age, tumor size ,TNM stage (p>0.05), but there was a significant difference between well differentiated OSCC(82.3 % PTEN positive) and poorly differentiated OSCC(14.3. 3 % PTEN positive) (P < 0.05) .PTEN protein expression showed correlation to lymph node metastasis (P <0.05) . 2. p27 showed in nuclear.In the tissues from Normal oral mucosa tissues ,92.5 % were positive for p27 protein . In the tissues from oral epithelial dysplasia ,90.9 % were positive for p27 protein .In the tissuesfromOSCC ,61.1 % were positive for p27 protein. p27 oncoprotein positive staining was found in 61.5% of well differentiared tumors,47.6%of moderately differentiated tumors and 42.8% of poorly differentiated tumors. p27 oncoprotein positive staining was found in 66.7% of nolymph node metastasis, but p27 oncoprotein positive staining was found in 41.7% of lymph node metastasis. p27 protein expression did not show correlation to sex and age , tumor size ,TNM stage (p>0.05) but there was a significant difference between well differentiated OSCC(61.5%p27positive) and poorly differentiated OSCC(42.8% p27 positive) (P < 0.05) .p27 protein expression showed correlation to lymph node metastasis (jP<0.05) 3. Overexpression of cyclinDl immunostaining was mostly nuclear. In the tissues from Normal oral mucosa tissues 14.2 % were positive for cyclinDl protein . In the tissues from oral epithelial dysplasia ,18.2 % were positive for cyclinDl protein .In the tissues from OSCC ,63% were positive for cyclinDl protein. cyclinDl oncoprotein positive staining was found in 54.6% of well differentiated tumors,71.4%of moderately differentiated tumors and 85.7% of poorly differentiated tumors .cyclinDl oncoprotein positive staining was found in59.5% of nolymph node metastasis,but cyclinDloncoprotein positive staining was found in 83.3% of lymph node metastasis. cyclinDl protein expression did not show correlation to sex and age, tumor size ,TNM stage, lymph node metastasis (p>0.05) but there was a significant difference between well differentiated OSCC(54.6% cyclinDl positive) and poorly differentiated OSCC(85.7% cyclinDl positive) (P < 0.05 ) .4. Not only between overpression of PTEN and p27 but also between expression of PTEN and cyclinDl showed significantly positive correlation , and there was negative correlationship between p27 and cyclinDl.Conclusions : The higher incidence of negative expression of PTEN protein in OSCC indicates that PTEN gene inactivation may play an important...