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