[Effects of transforming growth factor-beta/Smad signaling on the growth and apoptosis of human rhabdomyosarcoma cell line RD].
OBJECTIVE
To study the effects of TGF-beta/Smad signaling on the growth and apoptosis of human rhabdomyosarcoma cell line RD.


METHODS
Biosynthesized short hairpin RNA (shRNA) was transfected into RD cells by cation liposome vector to suppress Smad4 expression. The mRNA and protein expression of Smad4 in RD after shRNA-transfection were examined by RT-PCR and Western blot respectively. Immunofluorescent staining was used to detect the location of Smad2/3 in RD by laser scanning confocal microscopy. The viability of RD cells was examined by MTT method and (3)H-thymidine incorporation assay. The apoptosis of RD was examined by flow cytometry analysis and fluorescent staining.


RESULTS
The expression of mRNA and protein of Smad4 in RD were effectively suppressed by shRNA interference. Such suppression effectively interrupted the endogenous TGF-beta/Smad signaling and consequently blocked the translocation of Smad2/3. The interruption of endogenous TGF-beta/Smad signaling not only inhibited the growth of RD but also induced apoptosis of RD. Exogenous TGF-beta1 inhibited the growth of RD but did not influence the apoptosis of RD.


CONCLUSIONS
shRNA interference can effectively interrupt the TGF-beta/Smad signaling by suppressing the expression of Smad4. TGF-beta/Smad signaling subtly regulates the growth and apoptosis of RD.
Ye
Lü
L
Department of Pathology, West China Hospital, Sichuan University, Chengdu 610041, China.
Zhang
Hong-ying
HY
Yang
Guang-hua
GH
Bu
Hong
H
Guo
Hua
H
D017209:Apoptosis / Q000187:drug effects*; D045744:Cell Line, Tumor; D002467:Cell Nucleus / Q000378:metabolism; D049109:Cell Proliferation / Q000187:drug effects; D003593:Cytoplasm / Q000378:metabolism; D006801:Humans; D021381:Protein Transport; D034622:RNA Interference; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D034741:RNA, Small Interfering / Q000494:pharmacology; D012208:Rhabdomyosarcoma / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D015398:Signal Transduction; D051899:Smad2 Protein / Q000378:metabolism; D051900:Smad3 Protein / Q000378:metabolism; D051901:Smad4 Protein / Q000096:biosynthesis* / Q000235:genetics; D014162:Transfection; D053773:Transforming Growth Factor beta1 / Q000494:pharmacology*
D012333:RNA, Messenger; D034741:RNA, Small Interfering; C497782:SMAD2 protein, human; D051899:Smad2 Protein; D051900:Smad3 Protein; D051901:Smad4 Protein; D053773:Transforming Growth Factor beta1