Panaxadiol inhibits programmed cell death-ligand 1 expression and tumour proliferation via hypoxia-inducible factor (HIF)-1α and STAT3 in human colon cancer cells.
Pharmacol Res
; 155: 104727, 2020 05.
Article
em En
| MEDLINE
| ID: mdl-32113874
ABSTRACT
Panaxadiol is a triterpenoid sapogenin monomeric compound found in the roots of Panax ginseng and has a variety of biological activities such as neuroprotective and anti-tumour functions. However, the mechanisms how panaxadiol exerts the anticancer effects remain unknown. The current study aimed to investigate the potential activity of panaxadiol on programmed cell death-ligand 1 (PD-L1) expression and tumour proliferation in human colon cancer cells and to identify the underlying mechanism. Results showed that panaxadiol showed little cytotoxicity as assessed by a cytotoxicity assay and significantly inhibited PD-L1 expression at the protein and mRNA level in a dose-dependent manner. Furthermore, panaxadiol supressed the hypoxia-induced synthesis of hypoxia-inducible factor (HIF)-1α via the phosphoinositide 3-kinase (PI3K) and mitogen-activated protein kinase (MAPK) pathways without affecting HIF-1α degradation. Simultaneously, panaxadiol inhibited STAT3 activation through the JAK1, JAK2, and Src pathways. Moreover, pre-treatment with panaxadiol enhanced the activity of cytotoxic T lymphocytes (CTL) and regained their capacity of tumour cell killing in a T cell and tumour cell co-culture system. Immunoprecipitation showed that panaxadiol inhibited PD-L1 expression by blocking the interaction between HIF-1α and STAT3. The inhibitory effect of panaxadiol on tumour proliferation was further demonstrated by colony formation and EdU labelling assays. The anti-proliferative effect of panaxadiol was also proved by a xenograft assay in vivo. Taken together, the current work highlights the anti-tumour effect of panaxadiol, providing insights into development of cancer therapeutic through PD-L1 inhibition.
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Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Neoplasias do Colo
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Ginsenosídeos
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Antineoplásicos
Tipo de estudo:
Prognostic_studies
Limite:
Animals
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Humans
Idioma:
En
Ano de publicação:
2020
Tipo de documento:
Article