Skp2 regulates non-small cell lung cancer cell growth by Meg3 and miR-3163.
Maternally expressed gene 3 (Meg3) encodes a long non-coding RNA that has been shown to play a role in tumorigenesis. Skp2 is a component of the E3 ubiquitin ligase SCF that specifically promotes the ubiquitination-associated degradation of CDK inhibitor p27, and has been shown to promote cancer cell growth in different types of cancers, including non-small cell lung cancer (NSCLC). Nevertheless, a regulatory relationship between Meg3 and Skp2 has not been acknowledged. Here, we showed that NSCLC specimens had significant higher levels of Skp2 and significantly lower levels of Meg3, compared to paired non-tumor lung tissue. The levels of Meg3 and Skp2 were inversely correlated in NSCLC specimens. Patients with low Meg3 levels had a poor survival. Overexpression of Meg3 decreased Skp2 protein and increased p27 protein, while depletion of Meg3 increased Skp2 protein and decreased p27 protein in NSCLC cells, without altering Skp2 mRNA. These data suggest that the Skp2 may be regulated by Meg3 at post-transcriptional level. Bioinformatics analyses showed that miR-3163 bound to 3'-UTR of Skp2 mRNA in NSCLC cells to inhibit its translation, which was supported by luciferase reporter assay. Meg3 augmented the effects of miR-3163 on Skp2 mRNA, possibly through binding-induced function enhancement, which was supported by the double fluorescent in situ hybridization showing co-localized intracellular Meg3 and miR-3163 signals in NSCLC cells. The miR-3163 levels in NSCLC were not different from in NT, suggesting that the regulation of Skp2 in NSCLC by miR-3163 may require coordination of Meg3. Thus, our data suggest that Meg3 and miR-3163 may coordinate suppression of translation of Skp2 mRNA in NSCLC cells to inhibit NSCLC cell growth.
Department of Respiratory, The Fourth People's Hospital of Jinan, Jinan Clinical School of Taishan Medical College, 50 Shifan Road, Jinan, 250031, China.
Lin
L
Su
Department of Emergence, Jinan Military General Hospital, Jinan, 250031, China.
Dongrui
D
Han
Department of Technology, Shanghai Well Biomedical Technology Co., Ltd, Fudan Clinical Pathology Diagnostic Center, Shanghai, 200032, China.
Jingwen
J
Wu
Department of Respiratory, The Fourth People's Hospital of Jinan, Jinan Clinical School of Taishan Medical College, 50 Shifan Road, Jinan, 250031, China. xueyun_huo@163.com.
Xueyun
X
Huo
D020413:3' Untranslated Regions / Q000235:genetics; D000072283:A549 Cells; D001483:Base Sequence; D015153:Blotting, Western; D002289:Carcinoma, Non-Small-Cell Lung / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D049109:Cell Proliferation / Q000235:genetics*; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008175:Lung Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D035683:MicroRNAs / Q000235:genetics*; D008957:Models, Genetic; D062085:RNA, Long Noncoding / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D044786:S-Phase Kinase-Associated Proteins / Q000235:genetics* / Q000378:metabolism; D012689:Sequence Homology, Nucleic Acid
D020413:3' Untranslated Regions; C498907:MEG3 non-coding RNA, human; C000612068:MIRN3163 microRNA, human; D035683:MicroRNAs; D062085:RNA, Long Noncoding; D044786:S-Phase Kinase-Associated Proteins
Maternally expressed gene 3 (Meg3); Non-small cell lung cancer (NSCLC); Skp2; miR-3163