Expression And Significance Of PTEN And Caspase-3 In Vulvar Neoplasia

IntroductionThe carcinogenesis and progression of carcinoma are associated with many factors , which include the absence of tumor suppressors and inhibition of apop-tosis . Recent works indicate that the mutation of tumor suppressor gene PTEN and the depletion of the expression of apoptotic enzyme Caspase — 3 are associated with malignant changes of many carcinomas . The aim of this investigation was to study the expression of PTEN and Caspase - 3 in vulvar squamous cell carcinoma , VIN , nonneoplastic epithelial disorders of skin ( NNED) and normal skin in order to find their relation.Material and MethodsThirty cases of vulval squamous carcinoma;30 cases of VIN( 10 VIN I ,10 VIN II ,10 VIN III) ;30 cases of NNED ( 15 of them were squamous cell hyper-plasia, the otherl5 were lichen sclerosus) ; 10 cases of normal vulvar skin. We collected the clinical materials: age, clinical stage , histologic grade, nodal status.In our study , immunohistochemistry was employed with SP method. Rabbit anti - human PTEN monoclonal antibody ( from Maixim Biotech) was applied without dilution, whereas rabbit anti - human Caspase - 3 polyclonal antibody (from NeoMarker Biotech) were diluted in phosphate - buffered saline at dilution ratio of 1 ;200. All procedures were implemented according to the product illustration . Positive and negative controls were performed to ensure the results' reliability.The immunostaining of PTEN and Caspase - 3 was localized on the cytoplasm. A combined score for the immunostaining, based on both qualitative and quantitative immunostaining ,was composed by adding both the qualitative and quantitative score which was then divided into three group : score 0-2 ( - ) ; score3 ~ 4 ( + ) ; score > 4 ( ++ ).Statistical evaluation was performed using chi - square to differentiate the rates of different groups. SPSS version 13.0 software was employed to analyze all data.Resulte1. The expression of PTEN and Caspase - 3 among different groups PTEN protein negative rate was 43. 3% in vulvar squamous carcinoma, 16.7% in VIN , 6.7% in squamous cell hyperplasia , 13.3% in lichen sclerosus and 0% in normal vulvar skin. There were differences between VSCC and VIN (P < 0. 05) , but no significant difference of PTEN was dected between VSCC and VIN HI which negative rate was 30% . Between the two kinds of NNED, there were also no difference ( P > 0. 05). There were no difference between NNED and normal skin ( P >0.05)Caspase —3 protein negative rate was 46. 7% in vulvar squamous carcinoma, 23. 3% in VIN, 6. 7% both in squamous cell hyperplasia and lichen sclerosus and 0% in normal vulvar skin. There were differences between VSCC and VIN ( P <0. 05 ) . The negative rate of Caspase - 3 in VIN I ~ II was 15% , which was significant lower than that of VIN IH40% ( P <0.05) , but no significant difference of Caspase - 3 was dected between VSCC and VIN HI . Between the two kinds of NNED, there were no difference. There were also no difference between NNED and normal skin ( P > 0.05 ).2. The relationship of PTEN and Caspase -3 with vulvar carcinoma clinical and pathological materials.The rates of PTEN expression depletion showed significant correlation with clinical stage, pathological grades and lymph nodes metastases (P < 0. 05). The rates of Caspase - 3 expression depletion showed correlation with pathologi-...