Induction of apoptosis by Polygonatum odoratum lectin and its molecular mechanisms in murine fibrosarcoma L929 cells.
BACKGROUND
The Galanthus nivalis agglutinin (GNA)-related lectins have been reported to bear antiproliferative and apoptosis-inducing activities in cancer cells; however, the precise mechanisms by which GNA-related lectins induce cell death are still only rudimentarily understood.


METHODS
In the present study, Polygonatum odoratum lectin (designated POL), a mannose-binding specific GNA-related lectin, possessed a remarkable antiproliferative activity toward murine fibrosarcoma L929 cells. And, this lectin induced L929 cell apoptosis in a caspase-dependent manner. In addition, POL treatment increased the levels of FasL and Fas-Associated protein with Death Domain (FADD) proteins and resulted in caspase-8 activation. Also, POL treatment caused mitochondrial transmembrane potential collapse and cytochrome c release, leading to activations of caspase-9 and caspase-3. Moreover, POL treatment enhanced tumor necrosis factor alpha (TNFalpha)-induced L929 cell apoptosis.


RESULTS
Our data demonstrate for the first time that this lectin induces apoptosis through both death-receptor and mitochondrial pathways, as well as amplifies TNFalpha-induced L929 cell apoptosis.


CONCLUSIONS
These inspiring findings would provide new molecular basis for further understanding cell death mechanisms of the Galanthus nivalis agglutinin (GNA)-related lectins in future cancer investigations.
School of Life Sciences, Sichuan University, Chengdu 610064, China.
Bo
B
Liu
Bo
B
Zhang
Ming-Wei
MW
Min
He-Jiao
HJ
Bian
Long-Fei
LF
Chen
Qian
Q
Liu
Jin-Ku
JK
Bao
D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D020169:Caspases / Q000378:metabolism; D045744:Cell Line, Tumor; D004354:Drug Screening Assays, Antitumor; D005354:Fibrosarcoma / Q000201:enzymology / Q000473:pathology*; D051379:Mice; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism; D008517:Phytotherapy; D037121:Plant Lectins / Q000494:pharmacology*; D031384:Polygonatum / Q000378:metabolism*; D053218:Receptors, Death Domain / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
D037121:Plant Lectins; D053218:Receptors, Death Domain; D014409:Tumor Necrosis Factor-alpha; D020169:Caspases