BACKGROUND: Polo-like kinase 1 (PLK1) is highly expressed in many human cancers and regulates critical steps in mitotic progression. Previously, we have reported that PLK1 was overexpressed in non-small cell lung cancer (NSCLC), but the underlying molecular mechanisms are not well understood. By using microRNA (miR) target prediction algorithms, we identified miR-100 that might potentially bind the 3'-untranslated region of PLK1 transcripts. The purpose of this study was to investigate the roles of miR-100 and its association with PLK1 in NSCLC development. METHODS: Taqman real-time quantitative RT-PCR assay was performed to detect miR-100 expression 10 NSCLC tissues and corresponding nontumor tissues. Additionally, the expression of miR-100 in 110 NSCLC tissues and its correlation with clinicopathological factors or prognosis of patients was analyzed. Finally, the effects of miR-100 expression on growth, apoptosis and cell cycle of NSCLC cells by posttranscriptionally regulating PLK1 expression were determined. RESULTS: MiR-100 was significantly downregulated in NSCLC tissues, and low miR-100 expression was found to be closely correlated with higher clinical stage, advanced tumor classification and lymph node metastasis of patients. The overall survival of NSCLC patients with low miR-100 was significantly lower than that of those patients with high miR-100, and univariate and multivariate analyses indicated that low miR-100 expression might be a poor prognostic factor. Also, miR-100 mimics could lead to growth inhibition, G2/M cell cycle arrest and apoptosis enhancement in NSCLC cells. Meanwhile, miR-100 mimics could significantly inhibit PLK1 mRNA and protein expression and reduce the luciferase activity of a PLK1 3' untranslated region-based reporter construct in A549 cells. Furthermore, small interfering RNA (siRNA)-mediated PLK1 downregulation could mimic the effects of miR-100 mimics while PLK1 overexpression could partially rescue the phenotypical changes of NSCLC cells induced by miR-100 mimics. CONCLUSIONS: Our findings indicate that low miR-100 may be a poor prognostic factor for NSCLC patients and functions as a tumor suppressor by posttranscriptionally regulating PLK1 expression.
BACKGROUND:Polo-like kinase 1 (PLK1) is highly expressed in many humancancers and regulates critical steps in mitotic progression. Previously, we have reported that PLK1 was overexpressed in non-small cell lung cancer (NSCLC), but the underlying molecular mechanisms are not well understood. By using microRNA (miR) target prediction algorithms, we identified miR-100 that might potentially bind the 3'-untranslated region of PLK1 transcripts. The purpose of this study was to investigate the roles of miR-100 and its association with PLK1 in NSCLC development. METHODS: Taqman real-time quantitative RT-PCR assay was performed to detect miR-100 expression 10 NSCLC tissues and corresponding nontumor tissues. Additionally, the expression of miR-100 in 110 NSCLC tissues and its correlation with clinicopathological factors or prognosis of patients was analyzed. Finally, the effects of miR-100 expression on growth, apoptosis and cell cycle of NSCLC cells by posttranscriptionally regulating PLK1 expression were determined. RESULTS:MiR-100 was significantly downregulated in NSCLC tissues, and low miR-100 expression was found to be closely correlated with higher clinical stage, advanced tumor classification and lymph node metastasis of patients. The overall survival of NSCLCpatients with low miR-100 was significantly lower than that of those patients with high miR-100, and univariate and multivariate analyses indicated that low miR-100 expression might be a poor prognostic factor. Also, miR-100 mimics could lead to growth inhibition, G2/M cell cycle arrest and apoptosis enhancement in NSCLC cells. Meanwhile, miR-100 mimics could significantly inhibit PLK1 mRNA and protein expression and reduce the luciferase activity of a PLK1 3' untranslated region-based reporter construct in A549 cells. Furthermore, small interfering RNA (siRNA)-mediated PLK1 downregulation could mimic the effects of miR-100 mimics while PLK1 overexpression could partially rescue the phenotypical changes of NSCLC cells induced by miR-100 mimics. CONCLUSIONS: Our findings indicate that low miR-100 may be a poor prognostic factor for NSCLCpatients and functions as a tumor suppressor by posttranscriptionally regulating PLK1 expression.
Authors: G Wolf; R Elez; A Doermer; U Holtrich; H Ackermann; H J Stutte; H M Altmannsberger; H Rübsamen-Waigmann; K Strebhardt Journal: Oncogene Date: 1997-02-06 Impact factor: 9.867
Authors: Benjamin P Lewis; I-hung Shih; Matthew W Jones-Rhoades; David P Bartel; Christopher B Burge Journal: Cell Date: 2003-12-26 Impact factor: 41.582
Authors: Fei Li; Wai-Lung Ng; Troy A Luster; Hai Hu; Vladislav O Sviderskiy; Catríona M Dowling; Kate E R Hollinshead; Paula Zouitine; Hua Zhang; Qingyuan Huang; Michela Ranieri; Wei Wang; Zhaoyuan Fang; Ting Chen; Jiehui Deng; Kai Zhao; Hon-Cheong So; Alireza Khodadadi-Jamayran; Mousheng Xu; Angeliki Karatza; Val Pyon; Shuai Li; Yuanwang Pan; Kristen Labbe; Christina Almonte; John T Poirier; George Miller; Richard Possemato; Jun Qi; Kwok-Kin Wong Journal: Cancer Res Date: 2020-07-09 Impact factor: 12.701