Abstract:

Objective To establish an in vitro model for malignant melanoma with a malignant melanoma cell line MV3 on de-epidermized dermis （DED） and to study the invasion mode of melanoma cells. Methods A human de-epidermized dermis was prepared with some elements of basal membrane （BM）. Then, the reconstructed BM was identified by periodic acid schiff （PAS） staining and immunochemical staining for collagen Ⅳ. MV3 cells were seeded onto the prepared acellular dermis and maintained at the air-liquid interface for 13-15 days after 3-day submerged culture. Subsequently, the reconstructed malignant melanoma tissue was examined with hematoxylin and eosin （HE） staining and immunohistochemical staining with antibodies to S-100 protein and HMB45. Results No obvious changes were observed by naked eye in DED after the inoculation with MV3 cells. PAS staining and immunochemical staining for collagen Ⅳ confirmed the presence of BM component on the surface of DED and in the cavity of skin appendages in DED. Histological examination and immunochemical staining revealed that on the BM zone, MV3 cells grew into irregularly sized clusters; in the cavity of skin appendages, they attached onto the BM and aggregated into circular or bandlike shape; and at the lateral side of DED, they invasively and diffusely grew, broke through the BM and intruded into the surrounding tissues of DED. The reconstructed tissue was positive for S-100 protein and weakly positive for HMB45. Conclusions The in vitro model of malignant melanoma could be reconstructed by skin organ culture system. And, the experiment suggests that BM could affect the invasive growth pattern of malignant melanoma cells.

Key words: malignant melanoma;de-epidermized dermis;basement membrane;an in vitro model