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
. 2014 Sep 15;7(10):7114-22.
eCollection 2014.

Inhibition of beclin1 affects the chemotherapeutic sensitivity of osteosarcoma

Wenxin Wu  1 , Wei Li  2 , Yong Zhou  1 , Chaoyue Zhang  1
Affiliations

Inhibition of beclin1 affects the chemotherapeutic sensitivity of osteosarcoma

Wenxin Wu et al. Int J Clin Exp Pathol. .

Abstract

This study was conducted to explore the role of autophagy in cisplatin-resistant osteosarcoma. Cisplatin-resistant osteosarcoma cell line (MG63/DDP) was obtained from parental MG63 by treating cisplatin with an intermittent stepwise selection protocol. The autophagy in MG63/DDP and MG63 was fully analyzed by immunofluorescence and western blot analysis. Meanwhile, the autophagy and the sensitivity to cisplatin for MG63/DDP and MG63 after inhibition of beclin1 were analyzed in vitro and in vivo. Increased autophagy was observed in cisplatin resistant MG63/DDP cells and in the cisplatin-treated MG63 and MG63/DDP cells. Meanwhile, inhibition the beclin1 significantly inhibited the formation of autophagosome and resulted in the increase in the sensitivity to cisplatin for both MG63 and MG63/DDP cells in vitro and in vivo. In conclusion, autophagy is implicated in the cisplatin resistant osteosarcoma, and inhibition of beclin1 could be a target for improving osteosarcoma therapy.

Keywords: Cisplatin; MG63; autophagy; beclin1; osteosarcoma.

PubMed Disclaimer

Figures

Figure 1
Figure 1
The 50% inhibitory concentrations (IC50) of cisplatin in MG63 and MG63/DDP were calculated. MG63: Human osteosarcoma cell line; MG63/DDP is the cisplatin-resistant cell developed from the parental MG63 cells using an intermittent stepwise selection protocol. *means P < 0.05 compared to the controls with student’s T-test (n = 4).
Figure 2
Figure 2
Morphological analysis of MG63/DDP and MG63 cells. A: Morphological analysis of MG63 cells under light microscopy. B: Morphological analysis of MG63/DDP cells under light microscopy. C: Morphological analysis of MG63 cells under electron microscopy. D: Morphological analysis of MG63/DDP cells under electron microscopy. MG63: Human osteosarcoma cell line; MG63/DDP is the cisplatin-resistant cell developed from the parental MG63 cells using an intermittent stepwise selection protocol.
Figure 3
Figure 3
Autophagosome analysis of MG63/DDP and MG63 cells. A: MG63 cells were analyzed by immunofluorescence staining. B: MG63/DDP cells were analyzed by immunofluorescence staining. C: MG63 cells treated with DDP were analyzed by immunofluorescence staining. D: MG63/DDP cells treated with DDP were analyzed by immunofluorescence staining. MG63: Human osteosarcoma cell line; MG63/DDP is the cisplatin-resistant cell developed from the parental MG63 cells using an intermittent stepwise selection protocol; DDP: cisplatin.
Figure 4
Figure 4
(A) Immunoblotting of Beclin-1, LC3B-I and LC3B-II in MG63, MG63/DDP cells, and DDP treated MG63 and MG63/DDP cells. (B) Quantification of relative LC3B-II and LC3B-I abundance from data shown in (A). (C) Quantification of relative Beclin-1 abundance from data shown in (A). MG63: Human osteosarcoma cell line; MG63/DDP is the cisplatin-resistant cell developed from the parental MG63 cells using an intermittent stepwise selection protocol; DDP: cisplatin; LC3: microtubule-associated protein 1 light chain 3. *means P < 0.05 with student’s T-test (n = 4).
Figure 5
Figure 5
DZ affects the expression of beclin1. A: DZ inhibits the expression of beclin1 in mRNA levels in MG63/DDP cells. B: DZ inhibits the expression of beclin1 in protein level in MG63/DDP cells. MG63: Human osteosarcoma cell line; MG63/DDP is the cisplatin-resistant cell developed from the parental MG63 cells using an intermittent stepwise selection protocol; DDP: cisplatin; DZ: deoxyribozyme. *means P < 0.05 with student’s T-test (n = 4).
Figure 6
Figure 6
DZ affects the sensitivity to cisplatin. A: In vitro, DZ inhibits the expression of beclin1 in mRNA level in both MG63 and MG63/DDP cells treated with cisplatin. B: In vitro, DZ inhibits the expression of beclin1 in protein level in both MG63 and MG63/DDP cells treated with cisplatin.
Figure 7
Figure 7
DZ increases the sensitivity to cisplatin for both MG63 and MG63/DDP cells. MG63: Human osteosarcoma cell line; MG63/DDP is the cisplatin-resistant cell developed from the parental MG63 cells using an intermittent stepwise selection protocol; DZ: deoxyribozyme. *means P < 0.05 with student’s T-test (n = 4).
Figure 8
Figure 8
A: In vivo, DZ inhibits the expression of beclin1 in mRNA level in both MG63 and MG63/DDP cells after treatment with cisplatin. B: In vivo, DZ inhibits the expression of beclin1 in protein level in both MG63 and MG63/DDP cells after treatment with cisplatin. MG63: Human osteosarcoma cell line; MG63/DDP is the cisplatin-resistant cell developed from the parental MG63 cells using an intermittent stepwise selection protocol; DDP: cisplatin; DZ: deoxyribozyme. *means P < 0.05 with student’s T-test (n = 4).
Figure 9
Figure 9
DZ affects sensitivity to cisplatin in vivo. A: MG63 cells without treatment. B: MG63 cells treated with DZ. C: MG63 cells treated with cisplatin. D: MG63 cells treated with DZ and cisplatin. E: MG63 cells without treatment. F: MG63 cells treated with DZ. G: MG63 cells treated with cisplatin. H: MG63 cells treated with DZ and cisplatin. MG63: Human osteosarcoma cell line; MG63/DDP is the cisplatin-resistant cell developed from the parental MG63 cells using an intermittent stepwise selection protocol; DDP: cisplatin; DZ: deoxyribozyme. Mice were injected with MG63 cells or MG63/DDP cells (n = 6).
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Mirabello L, Troisi RJ, Savage SA. International osteosarcoma incidence patterns in children and adolescents, middle ages and elderly persons. Int J Cancer. 2009;125:229–234. - PMC - PubMed
    1. Ottaviani G, Jaffe N. The epidemiology of osteosarcoma. Cancer Treat Res. 2009;152:3–13. - PubMed
    1. Wittig JC, Bickels J, Priebat D, Jelinek J, Kellar-Graney K, Shmookler B, Malawer MM. Osteosarcoma: a multidisciplinary approach to diagnosis and treatment. Am Fam Physician. 2002;65:1123–1132. - PubMed
    1. Meyers PA, Schwartz CL, Krailo M, Kleinerman ES, Betcher D, Bernstein ML, Conrad E, Ferguson W, Gebhardt M, Goorin AM, Harris MB, Healey J, Huvos A, Link M, Montebello J, Nadel H, Nieder M, Sato J, Siegal G, Weiner M, Wells R, Wold L, Womer R, Grier H. Osteosarcoma: a randomized, prospective trial of the addition of ifosfamide and/or muramyl tripeptide to cisplatin, doxorubicin, and high-dose methotrexate. J. Clin. Oncol. 2005;23:2004–2011. - PubMed
    1. Huang J, Ni J, Liu K, Yu Y, Xie M, Kang R, Vernon P, Cao L, Tang D. HMGB1 promotes drug resistance in osteosarcoma. Cancer Res. 2012;72:230–238. - PubMed

MeSH terms

LinkOut - more resources