Reduced expression of actin-binding proteins, h-caldesmon and calponin h1, in the vascular smooth muscle inside melanoma lesions: an adverse prognostic factor for malignant melanoma.
BACKGROUND
The structural integrity of the blood vessels such as small arteries and veins is studied less frequently in malignant tumours than is angiogenesis. Objectives To clarify the characteristics of small arteries and small veins of melanoma lesions.


METHODS
We immunohistochemically investigated various types of melanocytic tumours using antibodies specific for endothelial and vascular smooth muscle cells, and analysed the relationship between the expression of these molecules in the blood vessels and the biological characteristics of the tumours. Formalin-fixed, paraffin-embedded sections of 15 cases of benign melanocytic tumours and 64 cases of malignant melanomas were investigated.


RESULTS
Significant suppression of expression of h-caldesmon (h-CD) and calponin h1 (CNh1) was observed in the blood vessels of malignant melanomas compared with both benign melanocytic tumours and normal tissues. In particular, the level of h-CD expression was inversely correlated with the frequency of metastasis and positively correlated with the survival rate in patients with malignant melanoma.


CONCLUSIONS
These findings suggest that alterations of the tumour vessels are an important factor for the prognosis of malignant melanoma, and that suppression of h-CD and CNh1 in the blood vessels in malignant melanoma reflects a structural fragility of the vessels, leading to their easy penetration by tumour cells. Defective expression of these molecules is likely to be an important marker for metastatic potential and for poor prognosis of melanoma.
Koganehira
Y
Y
Department of Dermatology, Molecular Oncology and Angiology, Research Center on Aging and Adaptation, Shinshu University School of Medicine, 3-1-1 Asahi, Matsumoto 390-8621, Japan.
Takeoka
M
M
Ehara
T
T
Sasaki
K
K
Murata
H
H
Saida
T
T
Taniguchi
S
S
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002135:Calcium-Binding Proteins / Q000032:analysis*; D002148:Calmodulin-Binding Proteins / Q000032:analysis*; D016009:Chi-Square Distribution; D002648:Child; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D008297:Male; D008545:Melanoma / Q000378:metabolism / Q000401:mortality / Q000473:pathology*; D008833:Microcirculation; D008840:Microfilament Proteins; D008854:Microscopy, Electron; D008875:Middle Aged; D009124:Muscle Proteins / Q000032:analysis; D009131:Muscle, Smooth, Vascular / Q000737:chemistry* / Q000473:pathology; D009363:Neoplasm Proteins / Q000032:analysis*; D009506:Nevus / Q000378:metabolism / Q000473:pathology; D011379:Prognosis; D012878:Skin Neoplasms / Q000378:metabolism / Q000401:mortality / Q000473:pathology*; D015996:Survival Rate; D000096985:Calponins
D002135:Calcium-Binding Proteins; D002148:Calmodulin-Binding Proteins; D008840:Microfilament Proteins; D009124:Muscle Proteins; D009363:Neoplasm Proteins; D000096985:Calponins