title: AEG-1 expression characteristics in human non-small cell lung cancer and its relationship with apoptosis.
abstract: Expression of astrocyte-elevated gene-1 (AEG-1), a novel oncoprotein, has been shown to promote cell growth and inhibit apoptosis, but the underlying molecular mechanisms and its functional significance in non-small cell lung cancer (NSCLC) remain to be elucidated. In the present study, statistical analysis displayed a significant correlation of AEG-1 expression with clinical staging (P = 0.048), differentiation (P = 0.019) and lymph node metastasis (P = 0.032). Simultaneously, the overall survival time in patients with higher AEG-1 expression was obviously shorter than that in patients with lower expression of AEG-1 (P < 0.001). Furthermore, we found that AEG-1 could inhibit apoptotic cell death in L-78 cells, as assessed by MTT, TUNEL and flow cytometry assay. After treating L-78 cells with AEG-1 siRNA, caspase-3 protein was significantly up-regulated and Bcl-2 protein was markedly decreased in L-78 cells, which was verified by the immunohistochemistry results about AEG-1, caspase-3 and Bcl-2. Furthermore, PI3K p110 protein and phosphorylated Akt were also largely attenuated by the treatment of AEG-1 siRNA. In conclusion, our results indicated that AEG-1 played a crucial role in the carcinogenesis of NSCLC and could inhibit apoptosis via activating cell survival signaling (enhancing the level of anti-apoptotic protein Bcl-2 and the activation of PI3K/Akt pathway).
authors.affiliation: Department of Pathology, The First Affiliated Hospital of Sun Yat-sen University, Zhongshan 2nd Road 58, Guangzhou 510080, Province Guangdong, People's Republic of China.
authors.forename: Zun-Fu
authors.initials: ZF
authors.lastname: Ke
authors.forename: Xiaopeng
authors.initials: X
authors.lastname: Mao
authors.forename: Cao
authors.initials: C
authors.lastname: Zeng
authors.forename: Shanyang
authors.initials: S
authors.lastname: He
authors.forename: Shuhua
authors.initials: S
authors.lastname: Li
authors.forename: Lian-Tang
authors.initials: LT
authors.lastname: Wang
mesh_terms: D000328:Adult; D000368:Aged; D017209:Apoptosis / Q000502:physiology*; D015153:Blotting, Western; D002289:Carcinoma, Non-Small-Cell Lung / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D015815:Cell Adhesion Molecules / Q000096:biosynthesis*; D045744:Cell Line, Tumor; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007150:Immunohistochemistry; D020287:In Situ Nick-End Labeling; D053208:Kaplan-Meier Estimate; D008175:Lung Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D008297:Male; D008565:Membrane Proteins; D008875:Middle Aged; D009367:Neoplasm Staging; D016601:RNA-Binding Proteins; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000502:physiology; D015854:Up-Regulation
chemical_list: D015815:Cell Adhesion Molecules; C483039:MTDH protein, human; D008565:Membrane Proteins; D016601:RNA-Binding Proteins