Assessing the clinical utility of measuring Insulin-like Growth Factor Binding Proteins in tissues and sera of melanoma patients.
BACKGROUND
Different Insulin-like Growth Factor Binding Proteins (IGFBPs) have been investigated as potential biomarkers in several types of tumors. In this study, we examined both IGFBP-3 and -4 levels in tissues and sera of melanoma patients representing different stages of melanoma progression.


METHODS
The study cohort consisted of 132 melanoma patients (primary, n = 72; metastatic, n = 60; 64 Male, 68 Female; Median Age = 56) prospectively enrolled in the New York University School of Medicine Interdisciplinary Melanoma Cooperative Group (NYU IMCG) between August 2002 and December 2006. We assessed tumor-expression and circulating sera levels of IGFBP-3 and -4 using immunohistochemistry and ELISA assays. Correlations with clinicopathologic parameters were examined using Wilcoxon rank-sum tests and Spearman-rank correlation coefficients.


RESULTS
Median IGFBP-4 tumor expression was significantly greater in primary versus metastatic patients (70% versus 10%, p = 0.01) A trend for greater median IGFBP-3 sera concentration was observed in metastatic versus primary patients (4.9 microg/ml vs. 3.4 microg/ml, respectively, p = 0.09). However, sera levels fell within a normal range for IGFBP-3. Neither IGFBP-3 nor -4 correlated with survival in this subset of patients.


CONCLUSIONS
Decreased IGFBP-4 tumor expression might be a step in the progression from primary to metastatic melanoma. Our data lend support to a recently-described novel tumor suppressor role of secreting IGFBPs in melanoma. However, data do not support the clinical utility of measuring levels of IGFBP-3 and -4 in sera of melanoma patients.
Yu
Jessie Z
JZ
Department of Dermatology, New York University School of Medicine, New York, NY, USA. yuj05@nyumc.org
Warycha
Melanie A
MA
Christos
Paul J
PJ
Darvishian
Farbod
F
Yee
Herman
H
Kaminio
Hideko
H
Berman
Russell S
RS
Shapiro
Richard L
RL
Buckley
Michael T
MT
Liebes
Leonard F
LF
Pavlick
Anna C
AC
Polsky
David
D
Brooks
Peter C
PC
Osman
Iman
I
D014408:Biomarkers, Tumor / Q000097:blood / Q000378:metabolism*; D018450:Disease Progression; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000097:blood / Q000378:metabolism*; D018974:Insulin-Like Growth Factor Binding Protein 4 / Q000097:blood / Q000378:metabolism; D008297:Male; D008545:Melanoma / Q000097:blood / Q000378:metabolism* / Q000473:pathology; D008875:Middle Aged
D014408:Biomarkers, Tumor; D018972:Insulin-Like Growth Factor Binding Protein 3; D018974:Insulin-Like Growth Factor Binding Protein 4