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Basic and clinical insights of Mu (μ)-opioid receptor in cancer

Ruidong Ding1† Yiming Zhao1† Jia Li1† Siyuan Zhao1 Dingyuan Su1 Yue Zhang2 Jia-Yi Wang3 Shuangyu Lv1* Xinying Ji1*
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1 Institute of Molecular Medicine, Henan International Joint Laboratory for Nuclear Protein Regulation, School of Basic Medical Sciences, Henan University, Kaifeng, Henan 475004, China
2 Department of Obstetrics and Gynecology, 988 Hospital of PLA, Zhengzhou, Henan 450000, China
3 San-Quan College, Xinxiang Medical University, Xinxiang, Henan 453003, China
Submitted: 1 December 2022 | Accepted: 13 March 2023 | Published: 29 March 2023
© 2023 by the Author(s). This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution 4.0 International License ( )

Cancer is a public health problem that is extremely harmful to people’s health. Most cancer patients experience severe pain in the advanced stage, which will seriously affect their prognosis. At present, opioids, such as morphine, have been used as the drug of choice for treating moderate to severe cancer-related pain. Mu (μ)-opioid receptor (MOR) is expressed in many different cancer cells. In this article, we present the relationship between MOR and tumor pathophysiology; summarize the molecular mechanism and effect of MOR on tumor proliferation and progression, tumor angiogenesis, tumor immunity, and cancer therapy; and propose the future research direction of MOR for cancer treatment. MOR could be as a promising prognostic biomarker and immune checkpoint in cancer therapy.

Mu-opioid receptor
Program for Innovative Talents of Science and Technology in Henan Province
Natural Science Foundation of Henan Province for Excellent Young Scholars
Medical Science and Technology Program of Henan Province
Program for Young Key Teacher of Henan Province

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Conflict of interest
The authors declare no conflict of interest.
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