Expression Of Gap Junction Proteins Connexin26 And Connexin43 In Human Transitional-Cell Carcinoma

Background: Gap junctions are specialized intercellular membrane channels composed of hexagonal arrangements of oligomeric proteins called connexins (Cxs), enabling cells to share directly ions and small water-soluble molecules(smaller than 1000Da)by the process called gap junction intercellular communication (GJIC). GJIC is considered to play an important role in the control of cell growth, proliferation, differentiation, the maintenance of homeostasis and morphogenesis. Tumor is a mass of abnormal tissue that is characterized by a tendency to independent and unrestrained growth. Correspondingly, disorders of GJIC are strongly associated with aberrant cell growth diseases, including cancer. Many studies overseas have confirmed that GJIC is responsible for the bystander effect(BE) seen in HSV-TK/GCV gene therapy. Due to their frequent functional alteration in tumors, the genes of gap junction proteins ? Cx ? have been classified as tumor suppressors. To date, the family of connexin genes comprises 21 members in the human genome. Cx gene expression has a certain tissue specificity, however, one cell type may express several connexin gene species. Cx26 and Cx43 expression in the transitional epithelium cell of urinal tracts have been reported. Human transitional-cell carcinoma(TCC) is one of the most common malignant in urinal system.We are going to study the expression of Cx26 and Cx43 in human TCC and its biological meaning. The methods and results are listed here as follows.The methods and the results of the experiment:1. We evaluated the expression of Cx26 and Cx43 by immunohistochemistry in normal urothelium tissues and TCC. Paraffin embedded specimens were cut into 4μm sections, deparaffinized and rehydrated. Endogenous peroxidase was neutralized with 3% hydrogen peroxide for 10 minutes at room temperature, followed by incubation in citrate buffer in a steam bath for 20 minutes. The slides were blocked using 5% BSA for 20 minutes before overnight incubation at 40C or 2 hours incubation at 200C with primary antibody. The sections were then washed in PBS and incubated for 20 minutes with biotinylated goat...