Purification of a lipoprotein lipase-inhibiting protein produced by a melanoma cell line associated with cancer cachexia.
A human melanoma cell line, SEKI, induces severe cachexia in tumor-bearing nude mice. A factor with the ability to inhibit lipoprotein lipase (LPL) was isolated from the conditioned medium of this cell line. This factor was 40-K-dalton protein, and designated temporarily as melanoma-derived LPL inhibitor (MLPLI). Amino acid sequencing revealed that the amino-terminal portion consists of SPLPITPV-AT--IR-P. Unexpectedly, the sequence, as far as determined, was identical to those of leukemia inhibitory factor (LIF), suggesting that MLPLI is a protein closely related to LIF. The findings that MLPLI inhibits LPL activity and that MLPLI is produced by human cancer cells inducing cancer cachexia also suggest that this protein is a candidate for the factor responsible for cancer cachexia.
Mori
M
M
Growth Factor Division, National Cancer Center Research Institute, Tokyo, Japan.
Yamaguchi
K
K
Abe
K
K
D000595:Amino Acid Sequence; D000818:Animals; D002100:Cachexia / Q000209:etiology / Q000378:metabolism*; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D008071:Lipoprotein Lipase / Q000037:antagonists & inhibitors*; D008545:Melanoma / Q000150:complications / Q000378:metabolism*; D051379:Mice; D008819:Mice, Nude; D008969:Molecular Sequence Data; D009368:Neoplasm Transplantation; D014176:Protein Biosynthesis; D011506:Proteins / Q000302:isolation & purification*; D014407:Tumor Cells, Cultured
D011506:Proteins; D008071:Lipoprotein Lipase