The Expression Of APOOBEC3G Protein In Condyloma Acuminatum And Some Neoplastic Skin Diseases

IntroductionHuman papilloma virus (HPV) is a kind of double-stranded and closed-looped deoxyribonucleic acid (DNA) virus with endemic genus and tissue-specificity. It can induce benign or malignant lesions around the anus and the genital vulva. The persistent HPV infection, which is caused by local cellular immunocompromice, is the important reason for the recurrence of condyloma acuminatum (CA) or the development of cervical cancer.Apolipoprotein B mRNA editing enzyme catalytic polypeptide-like protein 3G (APOBEC3G) is a natural immunologic factor which was found during the study of HPV. It belongs to the family of innate immunity. APOBEC3G can not only inhibit the replication of HIV, but also play important role in restrain HBV replication in a transient expression system of cotransfection cell line. Furthermore, it can obviously inhibit other kinds of retroviruses such as murine leukemia virus and simian immunodeficiency virus from different hosts. So APOBEC3G is considered to possess broad-spectrum antiviral activity. However, owing to the similar genetic structure and protein function with some members of cytosine deaminase family, the overexpression of APOBEC3G will lead to the increased genomic instability in cells, and thus involved in the development and progression of malignant tumors.The present study is to investigate the role of APOBEC3G in HPV infection related skin diseases. The expression of APOBEC3G protein in human CA and some malignant tumors of skin, with the control tissue of psoriasis and normal skin tissure, will be observed.Materials and Methods1,Twelve cases of CA with intact history and five cases of normal skin tissues were enrolled. Respectively, ten cases of each disease including squamous cell carcinoma, basal cell carcinoma, keratoacanthoma and psoriasis were also enrolled.2,The gender and age among patients with different diseases presented good comparability. Patients with system diseases or other skin diseases were excluded.MaterialsRabbit polyclonal to APOBEC3G-C-terminal(ab71634) SP-HistotstainTM-plus Kits 3,3'-diaminobenzidine, DAB KitImmunohistochemical stainingThe paraffin sections with 6-micrometer thickness were prepared. Antigens were repaired by EBA was used as primary antibody and PBS was used for negative control. The sections were observed under light microscope after DAB coloration, hematoxylin conter staining, dehydration, clearing and mounting.The methods of assessmentUnder the light microscope (×400), four fields were selected randomly from each section. The presentation of buffy or brown granules in cell member or intracytoplasm was considered positive. Semiquantitative integration of the staining intensity and the amount of positive cells in cells was used for manual assessment. The staining images were taken and analysed by computer. Then the optical density and positive percentage of each section were obtained.Statistical AnalysisThe SPSS16.0 software was used for data processing. X2 test was used for categorical data, and analysis of variance and LSD test were used for quantitative data. A p<0.05 was considered significant different.Results 1. In CA tissue, nine cases presented high expression and the positive rate reached 91.67%. In SCC and BCC tissues, respectively, four cases presented high expression and the positive rate was 60%. In KA tissue, five cases presented high expression and the positive rate was 70%.2. There was significant difference between CA/SCC/BCC/KA and control tissues (psoriasis and normal skin) on the distribution of positive expression. There was no significant difference between CA and the three skin neoplasm malignants or between psoriasis and normal skin.3. In CA tissue, the optical density and positive percentage were 17.48 and 33.51%, being the highest one. In psoriasis and normal skin, the two index were around 21 and 8%, being the lowest one. The results of SCC, BCC and KA were in the range of CA and control tissues.4. There was significant difference between CA/SCC/BCC/KA and control tissues (psoriasis and normal skin) on the optical density and positive percentage. Significant difference was seen between CA and the three skin neoplasm malignants. There was no significant difference among the three skin neoplasm malignants or between psoriasis and normal skin.Conclusion1. APOBEC3G protein was highly expressed in most HPV infected CA tissues.2. APOBEC3G protein was moderately expressed in some skin neoplasm malignancies such as SCC, BCC and KA.3. APOBEC3G protein was in low level of expression in psoriasis and normal skin.