Apolipoprotein D expression in cutaneous malignant melanoma.
OBJECTIVE
Apolipoprotein D (Apo D) is a protein component of the human plasma lipid transport system, and an androgen-regulated protein in both breast and prostate cancer cell lines. Our goal was to evaluate the expression of Apo D in malignant cutaneous melanomas, as well as to assess its possible relationship to clinical and pathological parameters.


METHODS
Apo D expression was analyzed in 32 paraffin-embedded tissues from patients with invasive cutaneous malignant melanomas, in 8 samples from in situ melanoma, and in 10 samples from 10 benign lesions (4 dermal melanocytic nevi, 4 compound melanocytic nevi, and 2 dysplastic melanocytic nevi), using immunohistochemical techniques.


RESULTS
The benign lesions were consistently negative for Apo D, whereas 3 of the 8 "in situ" melanomas (37.5%) and 12 of the 32 invasive melanomas (37.5%) showed positive immunostaining for Apo D. The percentage of Apo D-positive tumors was significantly higher in nodular than in superficial spreading melanomas (P = 0.011) and in melanomas with vertical growth phase than in melanomas with radial growth phase (P = 0.02). In addition, the percentage of Apo D-positive tumors was positively and significantly correlated with Clark's level of invasion (P = 0.046).


CONCLUSIONS
Apo D may be a new prognostic factor of unfavorable evolution in cutaneous malignant melanoma.
Miranda
Eva
E
Department of Pathology. Hospital de Cabueñes, Gijón, Spain.
Vizoso
Francisco
F
Martín
Arancha
A
Quintela
Isabel
I
Corte
María Daniela
MD
Seguí
María Eugenia
ME
Ordiz
Iratxe
I
Merino
Antonio Martínez
AM
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001053:Apolipoproteins / Q000096:biosynthesis*; D053399:Apolipoproteins D; D002648:Child; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008545:Melanoma / Q000378:metabolism* / Q000473:pathology; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D011379:Prognosis; D012878:Skin Neoplasms / Q000378:metabolism* / Q000473:pathology
D001053:Apolipoproteins; D053399:Apolipoproteins D