title: Immunohistochemical Analysis of Collagen IV and Laminin Expression in Spontaneous Melanoma Regression in the Melanoma-Bearing Libechov Minipig.
abstract: Spontaneous regression (SR) of human melanoma is a rare, well-documented phenomenon that is not still fully understood. Its detailed study cannot be performed in patients due to ethical reasons. Using the Melanoma-bearing Libechov Minipig (MeLiM) animals of various ages (from 3 weeks to 8 months) we implemented a long-term monitoring of melanoma growth and SR. We focused on immunohistochemical detection of two important extracellular matrix proteins, collagen IV and laminin, which are associated with cancer. We showed that SR of melanoma is a highly dynamic process. The expression of collagen IV and laminin correlated with changes in population of melanoma cells. Tumours of 3-week-old animals consisted primarily of melanoma cells with a granular expression of collagen IV and laminin around them. Thereafter, melanoma cells were gradually destroyed and tumour tissue was rebuilt into the connective tissue. Collagen IV expression slightly increased in tumours of 10-week-old pigs showing extracellular fibrous appearance. In tumours of older animals, areas lacking melanoma cells demonstrated a low expression and areas still containing melanoma cells a high expression of both proteins. We considered the age of 10 weeks as a turning point in the transition between tumour growth and SR of the MeLiM melanoma.
authors: Laboratory of Tumor Biology, Institute of Animal Physiology and Genetics AS CR , v.v.i, Libechov, Czech Republic ; Faculty of Science, Charles University , Prague, Czech Republic ; Department of Immunology, Third Faculty of Medicine, Charles University , Prague, Czech Republic.
authors: Daniela
authors: D
authors: Planska
authors: Laboratory of Natural Immunity, Institute of Microbiology AS CR , v.v.i., Prague, Czech Republic.
authors: Monika
authors: M
authors: Burocziova
authors: Laboratory of Tumor Biology, Institute of Animal Physiology and Genetics AS CR , v.v.i, Libechov, Czech Republic.
authors: Jan
authors: J
authors: Strnadel
authors: Laboratory of Tumor Biology, Institute of Animal Physiology and Genetics AS CR , v.v.i, Libechov, Czech Republic.
authors: Vratislav
authors: V
authors: Horak
keywords: MeLiM; collagen IV; laminin; porcine melanoma; spontaneous regression