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Differences in the post-translational modification of proteins by polyamines between weakly and highly metastatic B16 melanoma cells

✍ Scribed by Simone Beninati; Alberto Abbruzzese; Massimo Cardinali


Publisher
John Wiley and Sons
Year
1993
Tongue
French
Weight
717 KB
Volume
53
Category
Article
ISSN
0020-7136

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✦ Synopsis


The identification of (y-glutamy1)polyamines in proteolytic digest of proteins from the cytosolic and particulate fractions of B 16-F I 0 and B 16-F I OLr6 cell lines, originating from a spontaneous tumor in C57BL/6 mice, indicates that polyamines are incorporated into melanoma cell proteins by transglutaminases (TGases-EC 2.3.2.13). The levels of spermidine-derived protein cross-links were found to be inversely related with the metastatic potential of the 2 melanoma lines. Characterization of TGase activity in the 2 tumor cell lines showed 3 types of enzyme. The soluble cellular TGase activity (TGase C) was higher, and increased more, during the growth of the least metastasizing clone B I 6-F I OLr6 than in the B 16-F I0 line, which is the most metastasizing. Consistently, N1,N*-bis(y-glutamyl) spermidine, which is responsible for protein cross-link formation, was present in greater amount in B 16-F I OLr6 cells. The enhancement by theophylline of soluble-TGase activity and spermidine-dependent protein cross-links of B 16-F 10 cells reduced, with linear dose dependence, the ability of these cells to penetrate through human fibronectin-coated membrane in an in vitro assay of invasiveness. Our data confirm and extend 4To whom correspondence and reprint requests should be addressed.