Galectin-3 stabilizes heterogeneous nuclear ribonucleoprotein Q to maintain proliferation of human colon cancer cells.
Comparative analysis of proteomes using 5-fluorouracil (5-FU)-resistant human colon cancer cell line revealed that decreased galectin-3 expression was significantly associated with retarded proliferation. However, in the presence of 5-FU proliferation rate of cells with suppressed galectin-3 expression did not differ from that of cells with normal galectin-3 expression, even galectin-3 suppression augmented apoptosis. Mechanism by which galectin-3 regulates cancer cell proliferation has been identified in immunoprecipitates of the anti-galectin-3 antibody. Heterogeneous nuclear ribonucleoprotein Q (hnRNP Q) was identified as a protein interacting with galectin-3. Interestingly, while galectin-3 protein was not affected by the hnRNP Q level, its suppression was accompanied by a decrease in hnRNP Q expression. The present study demonstrates that galectin-3 stabilizes hnRNP Q via complex formation, and reduction in the hnRNP Q level leads to slow proliferation and less susceptibility to 5-FU.
Yoo
B C
BC
Research Institute, National Cancer Center, Madu2-dong, Goyang-si, 410-769, Gyeonggi-do, Korea.
Hong
S-H
SH
Ku
J-L
JL
Kim
Y-H
YH
Shin
Y-K
YK
Jang
S-G
SG
Kim
I-J
IJ
Jeong
S-Y
SY
Park
J-G
JG
D048868:Adaptor Proteins, Signal Transducing / Q000378:metabolism; D000595:Amino Acid Sequence; D000963:Antimetabolites / Q000378:metabolism; D017209:Apoptosis / Q000502:physiology; D018797:Cell Cycle Proteins; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D003110:Colonic Neoplasms / Q000378:metabolism* / Q000473:pathology; D015536:Down-Regulation; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D005472:Fluorouracil / Q000378:metabolism; D037502:Galectin 3 / Q000235:genetics / Q000378:metabolism*; D034441:Heterogeneous-Nuclear Ribonucleoproteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D008969:Molecular Sequence Data; D010750:Phosphoproteins / Q000378:metabolism; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism*; D011494:Protein Kinases / Q000378:metabolism; D020543:Proteome / Q000032:analysis; D019893:Ribosomal Protein S6 Kinases / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology; D058570:TOR Serine-Threonine Kinases
D048868:Adaptor Proteins, Signal Transducing; D000963:Antimetabolites; D018797:Cell Cycle Proteins; C087000:EIF4EBP1 protein, human; D037502:Galectin 3; D034441:Heterogeneous-Nuclear Ribonucleoproteins; D010750:Phosphoproteins; D020033:Protein Isoforms; D020543:Proteome; C425312:SYNCRIP protein, human; D011494:Protein Kinases; C546842:MTOR protein, human; D019893:Ribosomal Protein S6 Kinases; D058570:TOR Serine-Threonine Kinases; D048049:Extracellular Signal-Regulated MAP Kinases; D005472:Fluorouracil