
Interleukin 6 regulates the expression of programmed cell death ligand 1 in thyroid cancer
Author(s) -
Zhang GuoQiang,
Jiao Qiong,
Shen ChenTian,
Song HongJun,
Zhang HuiZhen,
Qiu ZhongLing,
Luo QuanYong
Publication year - 2021
Publication title -
cancer science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.035
H-Index - 141
eISSN - 1349-7006
pISSN - 1347-9032
DOI - 10.1111/cas.14752
Subject(s) - cancer research , stat3 , janus kinase , gene knockdown , signal transduction , metastasis , stat protein , medicine , cancer , thyroid cancer , biology , microbiology and biotechnology , apoptosis , biochemistry
Programmed cell death ligand 1 (PD‐L1), inducing T cell exhaustion to facilitate immune escape of tumor cells, is upregulated by interleukin 6 (IL‐6) in T cell lymphoma and ovarian cancer. The purpose of this study is to investigate the expression of IL‐6 and PD‐L1 in thyroid cancer, and whether IL‐6 regulates PD‐L1 expression. As a result, IL‐6 and PD‐L1 were highly expressed in thyroid cancer tissues. Multivariate logistic analysis showed that tumor size, distant metastasis, and risk stratification were significantly associated with IL‐6 expression ( P < .05), and multifocality, lymph node metastasis, distant metastasis, risk stratification, and IL‐6 expression were identified as the independent predictors of PD‐L1 expression ( P < .05). The invasiveness of thyroid cancer was significantly enhanced after IL‐6 treatment or PD‐L1 overexpression. PD‐L1 positive rate correlated with IL‐6 expression in cancer tissues ( P < .001), and after IL‐6 treatment, the PD‐L1 expression in TPC‐1 and BCPAP significantly increased. The mitogen‐activated protein kinase pathway (MAPK) and the Janus‐activated kinase (JAK)–signal transducers and activators of transcription 3 (STAT3) signaling pathways were activated by IL‐6, and the IL‐6–induced PD‐L1 expression decreased after treatment with these two signaling pathway inhibitors. Knockdown of transcription factors c‐Jun and stat3 suppressed the expression of PD‐L1 induced by IL‐6, and these two factors could bind to PD‐L1 gene promoter directly and promote its transcription. It is concluded that IL‐6 and PD‐L1 are overexpressed in thyroid cancer and are related to tumor invasiveness. IL‐6 upregulates PD‐L1 expression through the MAPK and JAK‐STAT3 signaling pathways, which function via transcription factors c‐Jun and stat3.