Stressed Jerusalem artichoke tubers (Helianthus tuberosus L.) excrete a protein fraction with specific cytotoxicity on plant and animal tumour cell.
Wounds from Jerusalem artichoke (Helianthus tuberosus L.) tubers excrete bioactive metabolites from a variety of structural classes, including proteins. Here we describe a protein specifically active against tumour cells arising either from human, animal or plant tissues. The non-tumour animal cells or the plant callus cells are not sensitive to these excreta. The active product was only obtained after a wound-drought stress of plant tubers. The cytotoxicity varies according to the tumour cell type. For instance, some human tumour cell lines and especially the human mammary tumour cells MDA-MB-231 were shown to be very susceptible to the active product. The active agent is shown to contain an 18-kDa polypeptide with homology to a superoxide dismutase (SOD). A 28-kDa polypeptide, related to an alkaline phosphatase (AP), was shown to be tightly linked to this 18-kDa polypeptide. The excreted 28-kDa polypeptide also displayed a consensus sequence similar to the group of DING proteins, but with a smaller molecular weight. The superoxide dismutase polypeptide was shown to be involved in the antitumour activity, but the presence of smaller factors (MW<10 kDa), such as salicylic acid, can enhance this activity.
Griffaut
B
B
EA 3296 ERTAC, "Tumeurs et Autosurveillance Cellulaire", Université Blaise-Pascal (Clermont-Ferrand II), Campus des Cézeaux, 24 Avenue des Landais, 63177 Aubière cedex, France.
Debiton
E
E
Madelmont
J C
JC
Maurizis
J C
JC
Ledoigt
G
G
D016960:Agrobacterium tumefaciens / Q000472:pathogenicity; D000595:Amino Acid Sequence; D000818:Animals; D045744:Cell Line, Tumor; D003603:Cytotoxins / Q000302:isolation & purification / Q000494:pharmacology*; D003890:Desiccation; D006368:Helianthus / Q000737:chemistry*; D006801:Humans; D008546:Melanoma, Experimental; D051379:Mice; D010935:Plant Diseases; D010940:Plant Proteins / Q000302:isolation & purification / Q000494:pharmacology*; D010941:Plant Tumors; D013482:Superoxide Dismutase / Q000494:pharmacology
D003603:Cytotoxins; D010940:Plant Proteins; D013482:Superoxide Dismutase