1. Spearman Correlation Analyses:
Effects of basic fibroblast factor (bFGF) on MMP-2, TIMP-2, and type-I collagen levels in human lung carcinoma fibroblasts Nakoman C1, Yazici P2, Resmi H1, Ay O1, Acikel U1, Atabey N1, Guner G1 1 Department of Biochemistry, Dokuz Eylul University School of Medicine, 2 Dokuz Eylul University School of Medicine Research Laboratory Inciralti, Izmir 35340, Turkey
Introduction:
Matrix metalloproteinases (MMP's) and tissue inhibitors of metalloproteinases (TIMP's) possess a preponderant role in the metabolism of the major extracellular matrix protein, collagen, and are thought to be important in the mechanism of tumor invasion. Lung cancer occupies the first position in mortality and the second position in incidence, among all cancers.
The objective of this investigation is to study quantitatively and to compare the effect of basic fibroblast growt factor (bFGF). We studied the effect of basic fibroblast growth factor (bFGF) on collagen, matrix metalloproteinase-2 (MMP-2), and tissue metalloproteinase inhibitor-2 (TIMP-2) levels in normal and carcinoma lung tissue fibroblast cultures.
Results:
Total collagen levels (μg/ mg tissue) showed no statistically significant differences between the carcinoma and normal tissue samples (p>0.05).
MMP-2, TIMP-2, total collagen, and type-1 collagen levels based on cell counts (103 cells) showed no statistically significant differences between the carcinoma and normal fibroblast cultures.
However, positive correlations were found between MMP-2 and TIMP-2 in normal (p = 0.016) and carcinoma (p = 0.001) tissue fibroblast cultures.
Positive correlations were also found between total collagen and TIMP-2 levels in normal and carcinoma tissue fibroblast cultures (p = and p= 0.032).
Total collagen and TIMP-2 levels also showed positive and strong correlations in all cultures except in 100 ng/ml bFGF concentrations.
In addition, type I collagen and MMP-2 levels showed positive significant correlations only in normal and carcinoma control cultures, while type I collagen and TIMP-2 levels showed positive correlations in all cultures except carcinoma fibroblasts at 100 ng/ml bFGF.
Materials-Methods:
MMP-2 was selected because of its high specificity in the degradation of type IV collagen, major component of the basal membrane. Type I collagen was selected for being one of the major collagen types in lung tissue.
This investigation has been carried out on carcinoma and normal lung tissue samples of the same cases (n=11) and on fibroblast cultures from the same tissues, obtained at surgical intervention at the Department of Cardiovascular Surgery, Dokuz Eylul University School of Medicine.
The hydroxyproline method of Taugard was used for the estimation of total collagen content at the tissue level. ELISA was used for the determination of MMP-2, TIMP-2 and type I collagen levels, while a colorimetric (Sircol) assay was applied for total collagen levels assays in the cell culture.
The effect of bFGF on MMP-2, TIMP-2, total collagen, and type I collagen levels of normal and carcinoma lung fibroblast cultures was investigated at 0, 10, and 100 ng/ml concentrations. For each pathological type and its normal counterpart, the levels of the four parameters were comparatively studied.
Statistical analysis was carried out using the Mann-Whitney-U test and possible correlations were searched using the Spearman correlation analysis method.
N0 = normal lung cell culture
N1 = normal lung cell culture (bFGF = 10 ng/ml)
N2 = normal lung cell culture (bFGF = 100 ng/ml)
T0 = carcinoma lung cell culture
T1 = carcinoma lung cell culture (bFGF = 10 ng/ml)
T2 = carcinoma lung cell culture (bFGF = 100 ng/ml)
Spearman Correlation Analyses:
MMP-2 and TIMP-2
Groups
R value
P value
significance N0
0.700
0.016 + T0
0.855
0.001 N1
0.118
0.729 - T1
0.579
0.062 N2
0.236
0.484 T2
-0.218
0.519
Total collagen and MMP-2
0.364
0.272
0.227
0.502 To
0.827
0.002
0.645
0.032
Total collagen and TIMP-2
0.845
0.727
0.011
0.945
0.000
0.373
0.259
Type I collagen and MMP-2
0.282
0.401
0.506
0.113
0.018
.0.958
Type I collagen and TIMP-2
0.955
0.800
0.003
0.582
0.060
0.627
0.039
0.836
Conclusion:
It may be concluded that bFGF does not affect MMP-2, TIMP-2, total collagen, and type-I collagen levels in fibroblast cultures grown from human carcinoma and normal lung tissues.
However, bFGF was noted, in vitro, to disturb the equilibrium which normally exists between the four parameters, both in normal and carcinoma tissue fibroblasts.