Skip to main content
Top
Published in: Clinical and Translational Oncology 3/2020

01-03-2020 | Cholangiocarcinoma | Research Article

Downregulation of MGMT promotes proliferation of intrahepatic cholangiocarcinoma by regulating p21

Published in: Clinical and Translational Oncology | Issue 3/2020

Login to get access

Abstract

Background

Intrahepatic cholangiocarcinoma (ICC) is one of the most devastating cancers of the gastrointestinal tract. It is crucial to determine the accurate prognostic factors and find new therapeutic strategies. Meanwhile, O6-methylguanine–DNA methyltransferase (MGMT) is associated with malignant tumor progression. Thus, further studies are needed to investigate whether MGMT plays a similar role in ICC.

Materials and methods

Quantitative real-time PCR, western blot, and immunohistochemistry staining were used to detect the expression of MGMT in ICC tissues. The correlations between MGMT expression and clinicopathologic features were analyzed. The cell-proliferation assay and colony-formation assay were applied to evaluate proliferation ability, while methylation-specific PCR were used to detect the methylation status of the MGMT promoter CpG island in ICC tissues and cells.

Results

Our study found that the expression of MGMT was decreased in ICC tissues when compared with paired normal tissues. In addition, we demonstrated that MGMT expression was positively correlated with overall survival rates and tumor histological grade. Silencing of MGMT significantly promoted cell proliferation in ICC. Further research showed that silencing of MGMT induced cells to enter S phase by inhibiting p21, p27, and Cyclin E expression, ultimately promoting ICC proliferation. We also demonstrated that the MGMT promoter was highly methylated in ICC, and the levels of MGMT and p21 mRNA increased after DNA demethylation. In addition, the levels of MGMT and p21 protein were positively correlated in ICC tissues.

Conclusion

MGMT may play a critical role in carcinogenesis and the development of ICC, and provides a new marker of clinical prognosis and target for ICC treatment.
Appendix
Available only for authorised users
Literature
4.
go back to reference Taylor-Robinson SD, Toledano MB, Arora S, Keegan TJ, Hargreaves S, Beck A, et al. Increase in mortality rates from intrahepatic cholangiocarcinoma in England and Wales 1968–1998. Gut. 2001;48(6):816–20.CrossRef Taylor-Robinson SD, Toledano MB, Arora S, Keegan TJ, Hargreaves S, Beck A, et al. Increase in mortality rates from intrahepatic cholangiocarcinoma in England and Wales 1968–1998. Gut. 2001;48(6):816–20.CrossRef
5.
go back to reference Pegg AE. Mammalian O6-alkylguanine-DNA alkyltransferase: regulation and importance in response to alkylating carcinogenic and therapeutic agents. Cancer Res. 1990;50(19):6119–29.PubMed Pegg AE. Mammalian O6-alkylguanine-DNA alkyltransferase: regulation and importance in response to alkylating carcinogenic and therapeutic agents. Cancer Res. 1990;50(19):6119–29.PubMed
18.
go back to reference el-Deiry WS, Tokino T, Velculescu VE, Levy DB, Parsons R, Trent JM et al. WAF1, a potential mediator of p53 tumor suppression. Cell. 1993;75(4):817–25.CrossRef el-Deiry WS, Tokino T, Velculescu VE, Levy DB, Parsons R, Trent JM et al. WAF1, a potential mediator of p53 tumor suppression. Cell. 1993;75(4):817–25.CrossRef
20.
go back to reference Waldman T, Kinzler KW, Vogelstein B. p21 is necessary for the p53-mediated G1 arrest in human cancer cells. Cancer Res. 1995;55(22):5187–90.PubMed Waldman T, Kinzler KW, Vogelstein B. p21 is necessary for the p53-mediated G1 arrest in human cancer cells. Cancer Res. 1995;55(22):5187–90.PubMed
Metadata
Title
Downregulation of MGMT promotes proliferation of intrahepatic cholangiocarcinoma by regulating p21
Publication date
01-03-2020
Published in
Clinical and Translational Oncology / Issue 3/2020
Print ISSN: 1699-048X
Electronic ISSN: 1699-3055
DOI
https://doi.org/10.1007/s12094-019-02140-9

Other articles of this Issue 3/2020

Clinical and Translational Oncology 3/2020 Go to the issue
Webinar | 19-02-2024 | 17:30 (CET)

Keynote webinar | Spotlight on antibody–drug conjugates in cancer

Antibody–drug conjugates (ADCs) are novel agents that have shown promise across multiple tumor types. Explore the current landscape of ADCs in breast and lung cancer with our experts, and gain insights into the mechanism of action, key clinical trials data, existing challenges, and future directions.

Dr. Véronique Diéras
Prof. Fabrice Barlesi
Developed by: Springer Medicine