Ontology highlight
ABSTRACT: Abstract
The propensity for breast cancer to metastasize to bone is coupled to the most common complaint among breast cancer patients: bone pain. Classically, this type of pain is treated using escalating doses of opioids, which lack long-term efficacy due to analgesic tolerance, opioid-induced hypersensitivity, and have recently been linked to enhanced bone loss. To date, the molecular mechanisms underlying these adverse effects have not been fully explored. Using an immunocompetent murine model of metastatic breast cancer, we demonstrated that sustained morphine infusion induced a significant increase in osteolysis and hypersensitivity within the ipsilateral femur through the activation of toll-like receptor-4 (TLR4). Pharmacological blockade with TAK242 (resatorvid) as well as the use of a TLR4 genetic knockout ameliorated the chronic morphine-induced osteolysis and hypersensitivity. Genetic MOR knockout did not mitigate chronic morphine hypersensitivity or bone loss. In vitro studies using RAW264.7 murine macrophages precursor cells demonstrated morphine-enhanced osteoclastogenesis that was inhibited by the TLR4 antagonist. Together, these data indicate that morphine induces osteolysis and hypersensitivity that are mediated, in part, through a TLR4 receptor mechanism.
SUBMITTER: Thompson AL
PROVIDER: S-EPMC10578422 | biostudies-literature | 2023 Nov
REPOSITORIES: biostudies-literature
Thompson Austen L AL Grenald Shaness A SA Ciccone Haley A HA Mohty Dieter D Smith Angela F AF Coleman Deziree L DL Bahramnejad Erfan E De Leon Erick E Kasper-Conella Logan L Uhrlab Jennifer L JL Margolis David S DS Salvemini Daniela D Largent-Milnes Tally M TM Vanderah Todd W TW
Pain 20230615 11
<h4>Abstract</h4>The propensity for breast cancer to metastasize to bone is coupled to the most common complaint among breast cancer patients: bone pain. Classically, this type of pain is treated using escalating doses of opioids, which lack long-term efficacy due to analgesic tolerance, opioid-induced hypersensitivity, and have recently been linked to enhanced bone loss. To date, the molecular mechanisms underlying these adverse effects have not been fully explored. Using an immunocompetent mur ...[more]