Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2020 Apr;235(4):3280-3291.
doi: 10.1002/jcp.29104. Epub 2019 Nov 6.

PCBP2 promotes the development of glioma by regulating FHL3/TGF-β/Smad signaling pathway

Jianhui Mao  1 , Zhaosheng Sun  1 , Yongjian Cui  2 , Naiyi Du  3 , Hong Guo  1 , Jianhui Wei  1 , Zhenmin Hao  3 , Lei Zheng  3
Affiliations

PCBP2 promotes the development of glioma by regulating FHL3/TGF-β/Smad signaling pathway

Jianhui Mao et al. J Cell Physiol. 2020 Apr.

Abstract

The purpose of this study was to investigate the role of Poly (C)-binding protein 2 (PCBP2) and the related signaling pathway in glioma progression. Quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry (IHC) were performed to measure PCBP2 messenger RNA and protein expression in glioma tissues or cells. Cell transfection was completed using Lipofectamine 2000. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, Transwell assay and flow cytometry assay were used to explore the effects of PCBP2 expression on biological behaviors of glioma cells. Western blot assay was used for the detection of pathway related proteins. Expression of PCBP2 in glioma tissues and cells were higher than that in paracancerous tissues and normal cells (both p < .01). Moreover, the elevated expression of PCBP2 was significantly correlated with tumor size (p = .001) and WHO stage (p = .010). Knockdown of PCBP2 could suppress proliferation, migration and invasion of glioma cells and promote apoptosis. Besides, the expression of transforming growth factor-β (TGF-β) pathway related proteins TGF-β1, p-Smad2 and p-Smad7 were decreased following the downregulation of PCBP2. PCBP2 also inhibited FHL3 expression by binding to FHL3-3'UTR. The inhibition of FHL3 could reverse the antitumor action caused by PCBP2 silencing. In vivo assay, PCBP2 was also found to inhibit the tumor growth of glioma. PCBP2 activates TGF-β/Smad signaling pathway by inhibiting FHL3 expression, thus promoting the development and progression of glioma.

Keywords: FHL3; PCBP2; TGF-β/Smad pathway; glioma.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Poly (C)‐binding protein 2 (PCBP2) was upregulated in glioma tissues. The relative expression of PCBP2 mRNA in glioma tissue specimens and noncancerous tissues were examined by quantitative real‐time polymerase chain reaction (qRT‐PCR) assay (a). The levels of PCBP2 in HEB cells and U251 cells were examined by qRT‐PCR assay (b). PCBP2 protein expression in noncancerous tissues and glioma tissues were examined by western blot analysis (c). The representative immunohistochemical (IHC) staining images showing the expression patterns of PCBP2 protein in noncancerous tissues and glioma tissues (×200) (d). Data are presented as mean ± SD (n  =  3). **p  <  .01. SD, standard deviation
Figure 2
Figure 2
The efficiency of si‐PCBP2 was confirmed by quantitative real‐time polymerase chain reaction (a) and Western blot analysis (b). Data are presented as mean ± SD (n = 3). ***p < .001
Figure 3
Figure 3
Effects of poly (C)‐binding protein 2 (PCBP2) expression on biological behaviors of glioma cells in vitro. The knockdown of PCBP2 expression could significantly inhibit proliferation (a), migration (b) and invasion (c) of glioma cells. Furthermore, inhibition of PCBP2 expression could promote cell apoptosis (d). Data are presented as mean ± SD (n = 3). *p < .05, **p < .01, and ***p < .001. SD, standard deviation
Figure 4
Figure 4
Poly (C)‐binding protein 2 (PCBP2) knockdown could promote FHL3 expression and suppress TGF‐β/Smad signaling pathway. The knockdown of PCBP2 could significantly enhance the expression of FHL3 in glioma cells (a and b). Knockdown of PCBP2 might inhibit the activity of TGF‐β/Smad signaling pathway (c). Data are presented as mean ± SD (n = 3). *p < .05, **p < .01, ***p < .001. SD, standard deviation
Figure 5
Figure 5
FHL3 was a potential target of poly (C)‐binding protein 2 (PCBP2) in glioma.The nucleotide sequence of FHL3 target binding site and the core recognition sequence are red (a). The loss of PCBP2 expression could reduce the luciferase activity of cell transfected by FHL3‐wt, but it did not influence the cells transfected by FHL3‐mt (b). The transfection of pLV‐FHL3 vector could distinctly enhance the expression of FHL3 (c and d), but had no significant influence on PCBP2 expression (e and f). Data are presented as mean ± SD (n  =  3). **p  <  .01, (NS, nonsignificant, p  >  .05)
Figure 6
Figure 6
The knockdown of FHL3 expression could enhance the expression patterns of TGF‐β/Smad signaling pathway proteins in glioma cells transfected by si‐PCBP2 vector. *p < .05, **p < .01
Figure 7
Figure 7
Inhibition of FHL3 expression could reverse the antitumor actions induced by the knockdown of poly (C)‐binding protein 2 (PCBP2) in glioma cells in vitro. Compared to the control groups, the cells proliferation (a), migration (b) and invasion (c) were significantly enhanced, while cell apoptosis (d) was downregulated in + si‐FHL3 group. The cells in control group were transfected by si‐PCBP2 vector only, while the cells in + si‐FHL3 group were cotransfected by si‐PCBP2 and si‐FHL3 vectors. Data are presented as mean ± SD (n = 3). *p < .05, **p < .01, and ***p < .001. SD, standard deviation
Figure 8
Figure 8
Tumor volume was significantly decreased in nude mice with PCBP2 knockdown (a and b); Tumor weight was obviously lower in si‐PCBP2 group than that in si‐NC group (c); The expression level of FHL3 was also upregulated in si‐PCBP2 group (d). *p < .05, **p < .01, ***p < .001
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Asnani, M. , Pestova, T. V. , & Hellen, C. U. T. (2016). PCBP2 enables the cadicivirus IRES to exploit the function of a conserved GRNA tetraloop to enhance ribosomal initiation complex formation. Nucleic Acids Research, 44(20), 9902–9917. - PMC - PubMed
    1. Chen, C. , Lei, J. , Zheng, Q. , Tan, S. , Ding, K. , & Yu, C. (2018). Poly(rC) binding protein 2 (PCBP2) promotes the viability of human gastric cancer cells by regulating CDK2. FEBS Open Bio, 8(5), 764–773. - PMC - PubMed
    1. Chen, Z. , Zhang, W. , Ni, L. , Wang, G. , Cao, Y. , Wu, W. , … Yang, H. (2016). Spatiotemporal expression of poly(rC)‐binding protein PCBP2 modulates Schwann cell proliferation after sciatic nerve injury. Cellular and Molecular Neurobiology, 36(5), 725–735. - PubMed
    1. Collier, B. , Goobar‐Larsson, L. , Sokolowski, M. , & Schwartz, S. (1998). Translational inhibition in vitro of human papillomavirus type 16 L2 mRNA mediated through interaction with heterogenous ribonucleoprotein K and poly(rC)‐binding proteins 1 and 2. The Journal of Biological Chemistry, 273(35), 22648–22656. - PubMed
    1. de Robles, P. , Fiest, K. M. , Frolkis, A. D. , Pringsheim, T. , Atta, C., St , Germaine‐Smith, C. , … Jette, N. (2015). The worldwide incidence and prevalence of primary brain tumors: A systematic review and meta‐analysis. Neuro‐Oncology, 17(6), 776–783. - PMC - PubMed

MeSH terms

LinkOut - more resources