Stressed Jerusalem artichoke tubers ( Helianthus tuberosus L.) excrete a protein fraction with specific cytotoxicity on plant and animal tumour cell

• Published in: Biochimica et biophysica acta Vol. 1770; no. 9; pp. 1324 - 1330
• Main Authors: Griffaut, B., Debiton, E., Madelmont, J.C., Maurizis, J.C., Ledoigt, G.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01-09-2007
• Subjects: Agrobacterium tumefaciens - pathogenicity; Alkaline phosphatase; Amino Acid Sequence; Animals; Cell Line, Tumor; Cytotoxins - isolation & purification; Cytotoxins - pharmacology; Desiccation; Helianthus - chemistry; Helianthus tuberosus; Humans; Melanoma, Experimental; Mice; Plant Diseases; Plant Proteins - isolation & purification; Plant Proteins - pharmacology; Plant stress; Plant Tumors; Superoxide dismutase; Superoxide Dismutase - pharmacology; Tumour; Helianthus tuberosus; Alkaline phosphatase; Superoxide dismutase; Tumour; Plant stress
• ISSN: 0304-4165; 0006-3002; 1872-8006
• DOI: 10.1016/j.bbagen.2007.06.007

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.