phalloidine and Skin-Neoplasms

Photodynamic therapy was found to be an effective therapy for local malignant tumors. This study demonstrated that 80 μg/ml Hedyotis corymbosa extracts with 0.8 J/cm(2) fluence dose caused M21 skin cancer cell death. Photoactivated H. corymbosa-induced M21 cell death is a typical apoptosis that is accompanied by nuclear condensation, externalization of phosphatidylserine and the changes in protein expression of apoptosis-related proteins, such as Bcl-2 and caspase family members. This study applied 2D electrophoresis to analyse the proteins involved in the photoactivated H. corymbosa-induced M21 cell apoptosis. We found 12 proteins to be markedly changed. According to the results of protein sequence analysis of these altered protein spots, we identified that the expression of cytoskeletal proteins and chaperones were involved in the photoactivated H. corymbosa-induced M21 cell apoptosis. We further demonstrated that photoactivated H. corymbosa caused a significant effect on the cytoskeleton distribution and mitochondrial activity in M21 cells. Based on the above findings, this study characterized the effects and mechanisms of the photoactivated H. corymbosa-induced apoptosis in M21 skin cancer cells.

Topics: Actin Cytoskeleton; Apoptosis; bcl-2-Associated X Protein; Caspases; Cell Line, Tumor; Cytochromes c; Cytoskeletal Proteins; Drugs, Chinese Herbal; Hedyotis; Humans; Melanoma; Mitochondria; Molecular Chaperones; Phalloidine; Photochemotherapy; Proteomics; Proto-Oncogene Proteins c-bcl-2; Skin Neoplasms

Distribution of actin filaments in human malignant keratinocytes was examined by immunofluorescence staining. The primary cultures were obtained from a squamous cell carcinoma, a basal cell carcinoma, and Bowen's disease. Rhodamine-phalloidin staining revealed that actin filaments were occasionally organized to form stress fibers, many short bundles with a ripple appearance, and regular arrays of actin patches. Some of these structures appeared in untransformed keratinocytes as a result of a brief exposure to a tumor promotor, TPA. These findings suggest that regulation of actin functions is involved in neoplastic processes from the very early stages and that alteration is persistent in neoplastic cells.

Topics: Actins; Aged; Bowen's Disease; Carcinoma, Basal Cell; Carcinoma, Squamous Cell; Female; Fluorescent Antibody Technique; Fluorescent Dyes; Humans; Male; Middle Aged; Phalloidine; Rhodamines; Skin Neoplasms; Tumor Cells, Cultured