Morphine counteracts the effects of paclitaxel in triple-negative breast cancer cells

Morphine Contributes to Epithelial-Mesenchymal Transition in Triple-Negative Breast Cancer Cells by Blocking COX-2 Methylation via Regulating the miR-23a-3p/DNMT3A Feedback

To investigate the effects and mechanisms of morphine on epithelial-mesenchymal transformation (EMT) in triple-negative breast cancer (TNBC). The levels of miR-23a-3p, DNMT3A, and COX-2 in tumor tissues from metastatic TNBC patients treated with morphine were assessed using qRT-PCR. Functional assays assessed morphine's impact on TNBC cell malignancy. Dual luciferase reporter and RNA pull-down assays investigated the interaction between miR-23a-3p and DNMT3A. miR-23a-3p inhibitor and DNMT3A siRNA were transfected into TNBC cells. Protein expression was analyzed by Western blot. Methylation status of miR-23a-3p and COX-2 was assessed via methylation-specific PCR. Rescue experiments were performed to research whether morphine modulates EMT in TNBC through COX-2 methylation regulation via the miR-23a-3p/DNMT3A feedback loop. The effects of morphine on TNBC in nude mice xenotransplantation were studied. In metastatic TNBC patients treated with morphine, miR-23a-3p and COX-2 expression were elevated, and DNMT3A levels were reduced. In TNBC cells, morphine enhanced migration, invasion, and EMT, and suppressed apoptosis. It upregulated miR-23a-3p and COX-2; downregulated DNMT3A; and inhibited methylation of miR-23a-3p and COX-2. miR-23a-3p directly inhibited DNMT3A expression. In morphine-treated TNBC cells, silencing DNMT3A reduced methylation of miR-23a-3p and COX-2. miR-23a-3p inhibitor suppressed migration, invasion, and EMT, and promoted apoptosis; however, these effects were reversed by DNMT3A silencing. In vivo, morphine promoted tumor EMT and metastasis in TNBC; reduced miR-23a-3p and COX-2 methylation; and decreased DNMT3A expression. Morphine accelerated EMT in TNBC by inhibiting COX-2 methylation through the miR-23a-3p/DNMT3A loop.

Anesthetic Techniques and Cancer Outcomes: What Is the Current Evidence?

It is almost 2 decades since it was first hypothesized that anesthesia technique might modulate cancer biology and thus potentially influence patients' long-term outcomes after cancer surgery. Since then, research efforts have been directed towards elucidating the potential pharmacological and physiological basis for the effects of anesthetic and perioperative interventions on cancer cell biology. In this review, we summarize current laboratory and clinical data. Taken together, preclinical studies suggest some biologic plausibility that cancer cell function could be influenced. However, available clinical evidence suggests a neutral effect. Observational studies examining cancer outcomes after surgery of curative intent for many cancer types under a variety of anesthetic techniques have reported conflicting results, but warranting prospective randomized clinical trials (RCTs). Given the large patient numbers and long follow-up times required for adequate power, relatively few such RCTs have been completed to date. With the sole exception of peritumoral lidocaine infiltration in breast cancer surgery, these RCTs have indicated a neutral effect of anesthetic technique on long-term oncologic outcomes. Therefore, unless there are significant new findings from a few ongoing trials, future investigation of how perioperative agents interact with tumor genes that influence metastatic potential may be justified. In addition, building multidisciplinary collaboration to optimize perioperative care of cancer patients will be important.

Reduced Taurine Synthesis Underlies Morphine-Promoted Lung Metastasis of Triple-Negative Breast Cancer

Background: The mechanisms underlying the progression and metastasis of triple-negative breast cancer (TNBC) in the context of extended morphine exposure remain poorly understood. Morphine consumption has been a pressing issue in many countries. While the physiological impact of extended morphine use is multifaceted, cancer patients with a history of extended morphine usage often have a poor prognosis. Methods: In this study, we investigated the impact of extended morphine treatment on the transcriptional profiles of TNBC. To this end, mice were administered morphine intraperitoneally for 14 days, followed by the implantation of EO771 cells, which are triple-negative breast cancer cells, into their mammary fat pad. After primary tumors were removed on the 38th day, a subset of mice was continuously given saline or morphine until the 68th day. Tumor size, organ metastasis, and tumor RNA expression were analyzed. Results: Our findings showed that extended exposure to morphine led to an increase in lung metastasis in the mouse model of triple-negative breast cancer. We analyzed RNA sequencing on tumors to compare their transcriptional profiles with or without metastasis. Through pathway analysis, we specifically examined the novel impact of morphine on the downregulation of taurine/hypotaurine biosynthesis. Given that morphine, droperidol (a dopamine receptor antagonist), and naloxone (an opioid receptor antagonist) might act through either opioid receptors or dopamine receptors, we further demonstrated that taurine mitigated EO771 cell invasion induced by morphine but not by droperidol or naloxone treatment. Additionally, morphine treatment markedly decreased the expression of GAD1, one of the enzymes essential for taurine biosynthesis, whereas droperidol and naloxone did not. Conclusions: The findings of morphine-induced reduction in GAD1 levels and the inhibition of invasion by taurine treatment suggest that taurine could serve as a potential supplement for triple-negative breast cancer patients who require morphine as part of their treatment regimen or due to their circumstances.

Vinpocetine increases the microsporicidal effect of albendazole on Encephalitozoon intestinalis

Microsporidia are obligate, intracellular, spore-forming eukaryotic fungi that infect humans and animals. In the treatment of disseminated microsporidiosis albendazole is the choice of drug. In recent years, antiparasitic activity of phosphodiesterase (PDE) enzyme inhibitors has been demonstrated against parasites and fungi, however, there is no information on microsporidia. Vinpocetine is currently used as a cerebral vasodilator drug and also as a dietary supplement to improve cognitive functions. Vinpocetine inhibits PDE1, so we aimed to investigate whether vinpocetine alone or in combination with albendazole has any effect on the spore load of Encephalitozoon intestinalis (E. intestinalis)-infected HEK293 cells. After determining the noncytotoxic concentrations of vinpocetine and albendazole on the host cell by MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, HEK293 cells were infected with E. intestinalis spores. Then, two different concentrations of vinpocetine, albendazole, and a combination of both drugs were applied to the cells with an interval of 72 h for 15 days. Spore load of the cells was analyzed by real-time PCR. After the last treatment, spore Deoxyribonucleic Acid (DNA) load was significantly reduced only in the group treated with 14 ng/ml albendazole. It was not different from control in groups treated with 7 ng/ml albendazole and 4-20 µM vinpocetine. However, the combination of vinpocetine significantly increased the effect of albendazole at both concentrations. To our knowledge, this is the first study to investigate the microsporicidal activity of vinpocetine as well as its combinations with albendazole. However, further studies are needed to investigate the mechanism of action and also confirm in vivo conditions.

Activation of epidermal growth factor receptors in triple-negative breast cancer cells by morphine; analysis through Raman spectroscopy and machine learning

Triple negative breast cancer (TNBC) is a very aggressive form of breast cancer, and the analgesic drug morphine has been shown to promote the proliferation of TNBC cells. This article investigates whether morphine causes activation of epidermal growth factor receptors (EGFR), the roles of μ-opioid and EGFR receptors on TNBC cell proliferation and migration. While examining the changes with molecular techniques, we also aimed to investigate the analysis ability of Raman spectroscopy and machine learning-based approach. Effects of morphine on the proliferation and migration of MDA.MB.231 cells were evaluated by MTT and scratch wound-healing tests, respectively. Morphine-induced phosphorylation of the EGFR was analyzed by western blotting in the presence and absence of μ-receptor antagonist naltrexone and the EGFR-tyrosine kinase inhibitor gefitinib. Morphine-induced EGFR phosphorylation and cell migration were significantly inhibited by pretreatments with both naltrexone and gefitinib; however, morphine-increased cell proliferation was inhibited only by naltrexone. While morphine-induced changes were observed in the Raman scatterings of the cells, the inhibitory effect of naltrexone was analyzed with similarity to the control group. Principal component analysis (PCA) of the Raman confirmed the epidermal growth factor (EGF)-like effect of morphine and was inhibited by naltrexone and partly by gefitinib pretreatments. Our in vitro results suggest that combining morphine with an EGFR inhibitor or a peripherally acting opioidergic receptor antagonist may be a good strategy for pain relief without triggering cancer proliferation and migration in TNBC patients. In addition, our results demonstrated the feasibility of the Raman spectroscopy and machine learning-based approach as an effective method to investigate the effects of agents in cancer cells without the need for complex and time-consuming sample preparation. The support vector machine (SVM) with linear kernel automatically classified the effects of drugs on cancer cells with ∼95% accuracy.

Endogenous opiates and behavior: 2022

This paper is the forty-fifth consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2022 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonists and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (1), the roles of these opioid peptides and receptors in pain and analgesia in animals (2) and humans (3), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (4), opioid peptide and receptor involvement in tolerance and dependence (5), stress and social status (6), learning and memory (7), eating and drinking (8), drug abuse and alcohol (9), sexual activity and hormones, pregnancy, development and endocrinology (10), mental illness and mood (11), seizures and neurologic disorders (12), electrical-related activity and neurophysiology (13), general activity and locomotion (14), gastrointestinal, renal and hepatic functions (15), cardiovascular responses (16), respiration and thermoregulation (17), and immunological responses (18).