title: Effects of TGF-β signaling blockade on human A549 lung adenocarcinoma cell lines.
abstract: Transforming growth factor β (TGF-β) is overexpressed in a wide variety of cancer types including lung adenocarcinoma (LAC), and the TGF-β signaling pathway plays an important role in tumor development. To determine whether blockade of the TGF-β signaling pathway can inhibit the malignant biological behavior of LAC, RNA interference (RNAi) technology was used to silence the expression of TGF-β receptor, type II (TGFβRII) in the LAC cell line, A549, and its effects on cell proliferation, invasion and metastasis were examined. Three specific small interfering RNAs (siRNAs) designed for targeting human TGFβRII were transfected into A549 cells. The expression of TGFβRII was detected by Western blot analysis. Cell proliferation was measured by MTT and clonogenic assays. Cell apoptosis was assessed by ﬂow cytometry. The invasion and metastasis of A549 cells were investigated using the wound healing and Matrigel invasion assays. The expression of PI3K, phosphorylated Smad2, Smad4, Akt, Erk1/2, P38 and MMPs was detected by Western blot analysis. The TGFβRII siRNA signiﬁcantly reduced the expression of TGFβRII in A549 cells. The knockdown of TGFβRII in A549 cells resulted in the suppression of cell proliferation, invasion and metastasis and induced cell apoptosis. In addition to the Smad-dependent pathway, independent pathways including the Erk MAPK, PI3K/Akt and p38 MAPK pathways, as well as the expression of MMPs and VEGF, were inhibited. In conclusion, TGF-β signaling is required for LAC progression. Therefore, the blockade of this signaling pathway by the down-regulation of TGFβRII using SiRNA may provide a potential gene therapy for LAC.
authors: Department of General Thoracic Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, P.R. China.
authors: Cheng-Cheng
authors: CC
authors: Xu
authors: Lei-Ming
authors: LM
authors: Wu
authors: Wei
authors: W
authors: Sun
authors: Ni
authors: N
authors: Zhang
authors: Wen-Shu
authors: WS
authors: Chen
authors: Xiang-Ning
authors: XN
authors: Fu
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D000077192:Adenocarcinoma of Lung; D017209:Apoptosis; D015153:Blotting, Western; D002289:Carcinoma, Non-Small-Cell Lung / Q000235:genetics; D045744:Cell Line, Tumor; D002465:Cell Movement; D049109:Cell Proliferation; D015972:Gene Expression Regulation, Neoplastic; D055785:Gene Knockdown Techniques; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D009361:Neoplasm Invasiveness; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering / Q000378:metabolism; D000077294:Receptor, Transforming Growth Factor-beta Type II; D018125:Receptors, Transforming Growth Factor beta / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction; D014162:Transfection; D016212:Transforming Growth Factor beta / Q000378:metabolism*; D014410:Tumor Stem Cell Assay
chemical_list: D012333:RNA, Messenger; D034741:RNA, Small Interfering; D018125:Receptors, Transforming Growth Factor beta; D016212:Transforming Growth Factor beta; D017346:Protein Serine-Threonine Kinases; D000077294:Receptor, Transforming Growth Factor-beta Type II