Morphine, a potential antagonist of cisplatin cytotoxicity, inhibits cisplatin-induced apoptosis and suppression of tumor growth in nasopharyngeal carcinoma xenografts

Natural Compounds for Preventing Age-Related Diseases and Cancers

Aging is a multifaceted process influenced by hereditary factors, lifestyle, and environmental elements. As time progresses, the human body experiences degenerative changes in major functions. The external and internal signs of aging manifest in various ways, including skin dryness, wrinkles, musculoskeletal disorders, cardiovascular diseases, diabetes, neurodegenerative disorders, and cancer. Additionally, cancer, like aging, is a complex disease that arises from the accumulation of various genetic and epigenetic alterations. Circadian clock dysregulation has recently been identified as an important risk factor for aging and cancer development. Natural compounds and herbal medicines have gained significant attention for their potential in preventing age-related diseases and inhibiting cancer progression. These compounds demonstrate antioxidant, anti-inflammatory, anti-proliferative, pro-apoptotic, anti-metastatic, and anti-angiogenic effects as well as circadian clock regulation. This review explores age-related diseases, cancers, and the potential of specific natural compounds in targeting the key features of these conditions.

Angiogenesis in nasopharyngeal carcinoma: insights, imaging, and therapeutic strategies

Nasopharyngeal carcinoma (NPC) is a highly prevalent head and neck malignancy in southern China frequently diagnosed at advanced stages owing to subtle early symptoms and associated metastasis. Angiogenesis emerges as a pivotal factor in NPC progression, with numerous angiogenesis-related factors showing aberrant expression and contributing to increased neovascularization within NPC tumors. These abnormal vessels not only nourish tumor growth but also facilitate metastasis, culminating in unfavorable patient outcomes. Multiple studies have demonstrated the applicability of various imaging techniques for assessing angiogenesis in NPC tumors, thus serving as a foundation for personalized treatment strategies and prognostic assessments. Anti-angiogenic therapies have exhibited significant potential for inhibiting NPC angiogenesis and exerting anti-tumor effects. To enhance efficacy, anti-angiogenic drugs are frequently combined with other treatment modalities to synergistically enhance anti-tumor effects while mitigating the side effects associated with single-agent therapies, consequently improving patient prognosis. Identifying the potential mechanisms and key targets underlying NPC angiogenesis and exploring more effective detection and treatment approaches holds promise for shaping the future of NPC diagnosis, treatment, and prognosis, thereby offering new avenues and perspectives for research and clinical practice.

Stimulator of Interferon Genes Pathway Activation through the Controlled Release of STINGel Mediates Analgesia and Anti-Cancer Effects in Oral Squamous Cell Carcinoma

Oral squamous cell carcinoma (OSCC) presents significant treatment challenges due to its poor survival and intense pain at the primary cancer site. Cancer pain is debilitating, contributes to diminished quality of life, and causes opioid tolerance. The stimulator of interferon genes (STING) agonism has been investigated as an anti-cancer strategy. We have developed STINGel, an extended-release formulation that prolongs the availability of STING agonists, which has demonstrated an enhanced anti-tumor effect in OSCC compared to STING agonist injection. This study investigates the impact of intra-tumoral STINGel on OSCC-induced pain using two separate OSCC models and nociceptive behavioral assays. Intra-tumoral STINGel significantly reduced mechanical allodynia in the orofacial cancer model and alleviated thermal and mechanical hyperalgesia in the hind paw model. To determine the cellular signaling cascade contributing to the antinociceptive effect, we performed an in-depth analysis of immune cell populations via single-cell RNA-seq. We demonstrated an increase in M1-like macrophages and N1-like neutrophils after STINGel treatment. The identified regulatory pathways controlled immune response activation, myeloid cell differentiation, and cytoplasmic translation. Functional pathway analysis demonstrated the suppression of translation at neuron synapses and the negative regulation of neuron projection development in M2-like macrophages after STINGel treatment. Importantly, STINGel treatment upregulated TGF-β pathway signaling between various cell populations and peripheral nervous system (PNS) macrophages and enhanced TGF-β signaling within the PNS itself. Overall, this study sheds light on the mechanisms underlying STINGel-mediated antinociception and anti-tumorigenic impact.

Mapping the Evidence for Opioid-Mediated Changes in Malignancy and Chemotherapeutic Efficacy: Protocol for a Scoping Review

BACKGROUND

Numerous reports contend opioids can augment or inhibit malignancy. At present, there is no consensus on the risk or benefit posed by opioids on malignancy or chemotherapeutic activity. Distinguishing the consequences of opioid use from pain and its management is challenging. Additionally, opioid concentration data is often lacking in clinical studies. A scoping review approach inclusive of preclinical and clinical data will improve our understanding of the risk-benefit relationship concerning commonly prescribed opioids and cancer and cancer treatment.

OBJECTIVE

The aim of the study is to map diverse studies spanning from preclinical to clinical regarding opioids with malignancy and its treatment.

METHODS

This scoping review will use the Arksey six stages framework to (1) identify the research question; (2) identify relevant studies; (3) select studies meeting criteria; (4) extract and chart data; (5) collate, summarize, and report results; and (6) conduct expert consultation. An initial pilot study was undertaken to (1) parameterize the extent and scale of existing data for an evidence review, (2) identify key factors to be extracted in systematic charting efforts, and (3) assess opioid concentration as a variable for its relevance to the central hypothesis. Six databases will be searched with no filters: MEDLINE, Embase, CINAHL Complete, Cochrane Library, Biological Sciences Collection, and International Pharmaceutical Abstracts. Trial registries will include ClinicalTrials.gov, Cochrane CENTRAL, International Standard Randomised Controlled Trial Number Registry, European Union Clinical Trials Register, and World Health Organization International Clinical Trials Registry. Eligibility criteria will include preclinical and clinical study data on opioids effects on tumor growth or survival, or alteration on the antineoplastic activity of chemotherapeutics. We will chart data on (1) opioid concentration from human subjects with cancer, yielding a "physiologic range" to better interpret available preclinical data; (2) patterns of opioid exposure with disease and treatment-related patient outcomes; and (3) the influence of opioids on cancer cell survival, as well as opioid-related changes to cancer cell susceptibility for chemotherapeutics.

RESULTS

This scoping review will present results in narrative forms as well as with the use of tables and diagrams. Initiated in February 2021 at the University of Utah, this protocol is anticipated to generate a scoping review by August 2023. The results of the scoping review will be disseminated through scientific conference proceedings and presentations, stakeholder meetings, and by publication in a peer-reviewed journal.

CONCLUSIONS

The findings of this scoping review will provide a comprehensive description of the consequences of prescription opioids on malignancy and its treatment. By incorporating preclinical and clinical data, this scoping review will invite novel comparisons across study types that could inform new basic, translational, and clinical studies regarding risks and benefits of opioid use among patients with cancer.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

PRR1-10.2196/38167.

Effect of Opioid Receptor Activation and Blockage on the Progression and Response to Treatment of Head and Neck Squamous Cell Carcinoma

Recent studies suggest that opioids have a role in the progression of HNSCC mediated by mu opioid receptors (MOR), however, the effects of their activation or blockage remains unclear. Expression of MOR-1 was explored in seven HNSCC cell lines using Western blotting (WB). XTT cell proliferation and cell migration assays were performed on four selected cell lines (Cal-33, FaDu, HSC-2, and HSC-3), treated with opiate receptor agonist (morphine), antagonist (naloxone), alone and combined with cisplatin. All four selected cell lines display an increased cell proliferation and upregulation of MOR-1 when exposed to morphine. Furthermore, morphine promotes cell migration, while naloxone inhibits it. The effects on cell signaling pathways were analyzed using WB, demonstrating morphine activation of AKT and S6, key proteins in the PI3K/AKT/mTOR axis. A significant synergistic cytotoxic effect between cisplatin and naloxone in all cell lines is observed. In vivo studies of nude mice harboring HSC3 tumor treated with naloxone demonstrate a decrease in tumor volume. The synergistic cytotoxic effect between cisplatin and naloxone is observed in the in vivo studies as well. Our findings suggest that opioids may increase HNSCC cell proliferation via the activation of the PI3K/Akt/mTOR signaling pathway. Moreover, MOR blockage may chemo-sensitize HNSCC to cisplatin.

Morphine stimulates cervical cancer cells and alleviates cytotoxicity of chemotherapeutic drugs via opioid receptor-dependent and -independent mechanisms

Morphine is frequently applied in cancer patients for pain management. However, its effects on cancer are not well understood but observed to be specific to certain cancer types. We previously revealed the stimulatory properties of morphine in esophageal carcinoma. This work addressed the effects of morphine and its underlying mechanisms in cervical cancer. Proliferation, apoptosis, and migration assays were performed to examine the effects of morphine alone and its combinatory effects with chemotherapeutic drugs. Immunoblotting and biochemical analysis were performed to determine the underlying mechanisms of morphine's action. Morphine promoted proliferation in opioid receptor-dependent manner and stimulated migration in opioid receptor-independent manner. However, morphine did not affect cervical cancer cell survival. Morphine also interfered with all tested chemotherapeutic drugs (e.g., cisplatin, 5-FU, and paclitaxel) and alleviates their efficacy. Mechanistically, morphine-stimulated growth via activating EGFR-mediated signaling pathways and is opioid-receptor-dependent; morphine-stimulated migration via activating RhoA-mediated signaling pathways and this is opioid receptor-independent. Our work suggests a strong correlation of this opioid receptor on growth factor signaling to stimulate growth and opioid receptor-independent activation of RhoA and consequent migration. Our findings have the potential to guide the clinical use of morphine for patients with cervical cancer.

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

Background & objectives

Several studies have provided evidence that opioids may play a role in cancer recurrence and metastasis. Multiple research data indicate that morphine can act as a proliferative or suppressive agent on tumour cells depending on the applied concentration. Therefore, this study was aimed to investigate whether the presence of clinically relevant concentrations of morphine has any effect on the efficacy of paclitaxel, a widely used chemotherapeutic drug, on the viability and apoptosis of human triple-negative breast cancer cell line.

Methods

MDA.MB.231 cells were treated with paclitaxel in the presence or absence of morphine and examined for cell proliferation by the MTT assay. In addition, the effect of morphine on paclitaxel-induced apoptosis was investigated by flow cytometric assay and by the ratio of Bax/Bcl-2 mRNA expression levels with quantitative real-time (qRT)-PCR.

Results

Morphine significantly increased the proliferation of breast cancer cells at low concentrations (0.1-2.5 μM) but higher concentrations showed cytotoxic effect. Pre-treatment with 0.1 or 1 μM of morphine decreased the paclitaxel-induced cytotoxicity, the proportion of apoptotic cell, and the ratio of Bax/Bcl-2 mRNA expressions.

Interpretation & conclusions

Our data suggest that morphine promotes breast cancer cell viability at clinically relevant plasma concentrations and reduces the apoptotic effect of paclitaxel. This interaction may be very important in clinical settings; however, more studies are needed to explore the plausible mechanisms of interaction and to correlate such findings through in vivo animal studies as well as clinically.

Morphine promotes migration and lung metastasis of mouse melanoma cells

BACKGROUND

Morphine is an analgesic agent used for cancer pain management. There have been recent concerns that the immunosuppressant properties of morphine can also promote cancer metastasis. Morphine is an agonist for toll like receptor 4 (TLR4) that has a dual role in cancer development. The promotor or inhibitor role of morphine in cancer progression remains controversial. We investigated the effects of morphine on migration and metastasis of melanoma cells through TLR4 activation.

METHODS

Mouse melanoma cells (B16F10) were treated with only morphine (0, 0.1, 1, and 10 μM) or in combination with a TLR4 inhibitor (morphine10 μM +CLI-095 1μM) for either 12 or 24 hours. Migration of cells was analyzed by transwell migration assays. Twenty C57BL/6 male mice were inoculated with B16F10 cells via the left ventricle of the heart and then randomly divided into two groups (n = 10 each) that received either morphine (10 mg.kg^-1, sub-q) or PBS injection for 21 days (control group). Animals were euthanized and their lungs removed for evaluation of metastatic nodules.

RESULTS

Morphine (0.1, 1, and 10 μM) increased cell migration after 12 hours (p < 0.001) and after 24 hours of treatment with morphine (10 μM) (p < 0.001). Treatment with CLI-095 suppressed migration compared to cells treated with morphine alone (p < 0.001). Metastatic nodules in the morphine-treated group (64 nodules) were significantly higher than in the control group (40 nodules) (p < 0.05).

CONCLUSION

Morphine increases the migration and metastasis of mouse melanoma cells by activating TLR4.

Perioperative pain, analgesics and cancer-related outcomes: where do we stand?

Cancer-related pain is one of the most common and debilitating symptoms among cancer patients. Undertreated cancer-related pain interferes with daily activities and increases morbidity and mortality. While opioids continue to play an essential role in treating moderate to severe cancer-related pain, they are associated with many adverse effects including misuse. While preclinical and retrospective studies have shown a negative association between opioid use and cancer outcomes, randomized control trials demonstrate that opioid use does not influence cancer recurrence. Additionally, analgesics and adjuvants used for perioperatively or chronic pain control are unlikely to improve oncological outcomes. This article focuses on the pharmacological management of cancer-related pain and offers an overview regarding the use of these medications perioperatively and the cancer outcomes.

Morphine promotes angiogenesis by activating PI3K/Akt/HIF-1α pathway and upregulating VEGF in hepatocellular carcinoma

Background

Hepatocellular carcinoma (HCC) is characterized by the neo-angiogenesis induced by tumor and adjacent cells. It is a leading cancer-related cause of death. Morphine has effects on angiogenesis with pro-angiogenic or anti-angiogenic phonotypes. This study explores the function of morphine on cancer cell growth, angiogenesis and the underlying mechanism in HCC.

Methods

Morphine was used to treat BEL-7402 or HCC-LM3 cells and human umbilical vein endothelial cells (HUVECs) were subsequently incubated in the conditioned media (CM) of HCC cells. The potential effects of cell proliferation, migration and tube formation of CM-treated HUVECs were investigated. Furthermore, the angiogenesis regulated factors of VEGFA, PIGF, ANG-1, ANG-2, FGF-1 and FGF-2 were assessed. siRNA and LY294002 were further used to explore the mechanism mediating the effects of morphine on the angiogenesis pathway. The neovascularization effect by morphine was confirmed through the use of human HCC cancer heterotopic mouse model in vivo.

Results

A significantly increased cell proliferation, migration, and tube formation effect of HUVECs induced by the CM from HCC cell lines treated with morphine was observed. More VEGFA secretion in CM from LM3 or BEL-7402 cell lines was found than the controls (P=0.03 and P=0.027, respectively). VEGFA knock-down could significantly reverse cell proliferation, migration and tube formation induced by the CM from HCC cell lines with morphine treatment. Further molecular experiments indicated that VEGFA secretion was activated by morphine potentially through the PI3K/Akt/HIF-1α pathway. Morphine-induced neovascularization was also observed by the IHC of CD31 and VEGFA.

Conclusions

Morphine promotes angiogenesis in hepatocellular carcinoma possibly through the activation of the PI3K/Akt/HIF-1α pathway and VEGFA stimulation.

Molecular mechanisms of the microRNA-132 during tumor progressions

Cancer as one of the leading causes of human deaths has always been one of the main health challenges in the world. Despite recent advances in therapeutic and diagnostic methods, there is still a high mortality rate among cancer patients. Late diagnosis is one of the main reasons for the high ratio of cancer related deaths. Therefore, it is required to introduce novel early detection methods. Various molecular mechanisms are associated with the tumor progression and metastasis. MicroRNAs (miRNAs) are a class of non-coding RNAs (ncRNAs) family that has important functions in regulation of the cellular processes such as cell proliferation, apoptosis, and tumor progression. Moreover, they have higher stability in body fluids compared with mRNAs which can be introduced as non-invasive diagnostic markers in cancer patients. MiR-132 has important functions as tumor suppressor or oncogene in different cancers. In the present review, we have summarized all of the studies which have been reported the role of miR-132 during tumor progressions. We categorized the miR-132 target genes based on their cell and molecular functions. Although, it has been reported that the miR-132 mainly functions as a tumor suppressor, it has also oncogenic functions especially in pancreatic tumors. MiR-132 mainly exerts its roles during tumor progressions by regulation of the transcription factors and signaling pathways. Present review clarifies the tumor specific molecular mechanisms of miR-132 to introduce that as an efficient non-invasive diagnostic marker in various cancers.

Morphine Deteriorates Cisplatin-Induced Cardiotoxicity in Rats and Induces Dose-Dependent Cisplatin Chemoresistance in MCF-7 Human Breast Cancer Cells

Morphine (MOR) is a strong analgesic that is often used in treatment of severe pains during cancer treatment, and thus might be concomitantly used with anticancer drugs as cisplatin (CP). The aim of the current study was to investigate the mechanisms by which MOR can affect CP-induced cardiotoxicity and to explore effects of MOR on the cytotoxic efficacy of CP. MOR (10 mg/kg/day i.p.) was administered to rats for 10 days, with or without 7.5 mg/kg CP single i.p. dose at day 5 of the experiment. In addition, MOR and/or CP were administered to MCF-7 cells to test their cytotoxicity. Compared to control, CP caused cardiotoxic effects manifested by significant increase in serum enzymatic markers; creatine kinase-MB and lactate dehydrogenase, with histopathological cardiac damage. In addition, CP caused cardiac oxidative stress, manifested by significant increased tissue lipid peroxidation product; malondialdehyde and nitric oxide, with significant decrease in tissue antioxidants as reduced glutathione, superoxide dismutase and catalase compared to control. Furthermore, CP significantly increased tissue proinflammatory cytokines; TNF-α and IL-6, as well as upregulated the apoptotic marker; caspase 3 compared to control. MOR/CP combination significantly deteriorated all tested parameters compared to CP alone. In MCF-7 breast cancer cells, administration of MOR in concentrations of 0.1, 1, 10 or 30 μM concomitantly with 1 or 10 μM CP caused dose-dependent reduction in CP-induced cytotoxicity in vitro. In conclusion, MOR administration might deteriorate CP-induced cardiotoxicity during cancer chemotherapy through oxidant, pro-inflammatory and apoptotic mechanisms, and might reduce CP chemotherapeutic efficacy.

Morphine may act via DDX49 to inhibit hepatocellular carcinoma cell growth

Pain in hepatocellular carcinoma (HCC) is a frequent cause of low quality of life, and morphine is routinely used as a first-line opiate analgesic in HCC. Morphine may exert not only analgesic effects but also anti-cancer effects via unknown mechanisms. Here we show that morphine can inhibit HCC cell proliferation. We further show that DEAD-box helicase 49 (DDX49) is up-regulated in HCC tumors, and that knocking down the DDX49 gene decreases tumor formation in vivo and in vitro, as well as reduces tumor metastasis in vivo. Morphine decreases DDX49 expression in HCC cells. Our results suggest that DDX49 contributes to HCC, and that morphine may exert anti-cancer effects by down-regulating it.

Morphine Stimulates Migration and Growth and Alleviates the Effects of Chemo Drugs via AMPK-Dependent Induction of Epithelial-Mesenchymal Transition in Esophageal Carcinoma Cells

The role of morphine, an opioid analgesic drug, in cancer biology has increasingly garnered attention due to its frequent usage in postoperative period for pain management in cancer patients. In this work, we demonstrated that morphine, at clinically relevant concentrations, stimulated migration and growth, and alleviated chemo drugs' efficacy in esophageal carcinoma cells. Although morphine did not affect survival, it protected esophageal carcinoma cells from chemo drugs-induced apoptosis. Mechanistical studies showed that morphine increased RhoA but not Rac1 activity. In addition, morphine activated AMP-activated protein kinase (AMPK) pathway, induced epithelial-mesenchymal transition (EMT) via upregulating Snail and Slug levels, and increased oxidative stress in esophageal carcinoma cells. Rescue studies further demonstrated that the stimulatory effects of morphine in esophageal carcinoma cells are through activation of AMPK pathway but not RhoA or opioid receptor. In addition, morphine induced EMT in an AMPK-dependent manner whereas increased RhoA activity in an AMPK-independent manner. Our work demonstrates the protective role of morphine on esophageal carcinoma cells via AMPK activation, which may provide a new guide in clinical use of morphine for patients with esophageal carcinoma.

Fentanyl stimulates tumor angiogenesis via activating multiple pro-angiogenic signaling pathways

Angiogenesis plays a vital role in tumor progression and metastasis. To better understand the role of anesthesia in tumor biology, we previously reported that bupivacaine displayed the inhibitory effects in endothelial cells. In this work, we demonstrated that fentanyl, an opioid medication commonly used in cancer patients, stimulated tumor angiogenesis. We found that fentanyl at nanomolar concentrations significantly stimulated capillary network formation of human lung tumor-associated endothelial cell (HLT-EC) in a similar manner as vascular endothelial growth factor (VEGF), and furthermore that the stimulatory effect of fentanyl was mainly involved in early stage of HLT-EC vascular structure assembly. Particularly, fentanyl significantly increased HLT-EC growth and migration. Fentanyl also protected HLT-EC from apoptosis induced by growth factor withdrawal. In contrast, the same concentrations of fentanyl did not affect human lung cancer cell growth and survival. Fentanyl stimulated migration of some but not all tested human lung cancer cells. Mechanism analysis suggested that fentanyl activates multiple pro-angiogenic signaling pathways, including VEGFR2/FAK/PI3K/Akt and small GTPases. Our work systematically demonstrates that fentanyl stimulates tumor angiogenesis via activating multiple pro-angiogenic signaling pathways. Our findings highlight the potential adverse effect of fentanyl in cancer patients.

Non-coding RNAs in drug resistance of head and neck cancers: A review

Head and neck cancer (HNC), which includes epithelial malignancies of the upper aerodigestive tract (oral cavity, oropharynx, pharynx, hypopharynx, larynx, and thyroid), are slowly but consistently increasing, while the overall survival rate remains unsatisfactory. Because of the multifunctional anatomical intricacies of the head and neck, disease progression and therapy-related side effects often severely affect the patient's appearance and self-image, as well as their ability to breathe, speak, and swallow. Patients with HNC require a multidisciplinary approach involving surgery, radiation therapy, and chemotherapeutics. Chemotherapy is an important part of the comprehensive treatment of tumors, especially advanced HNC, but drug resistance is the main cause of poor clinical efficacy. The most important determinant of this phenomenon is still largely unknown. Recent studies have shown that non-coding RNAs have a crucial role in HNC drug resistance. In addition, they can serve as biomarkers in the diagnosis, treatment, and prognosis of HNCs. In this review, we summarize the relationship between non-coding RNAs and drug resistance of HNC, and discuss their potential clinical application in overcoming HNC chemoresistance.

Circular RNA HIPK3: A Key Circular RNA in a Variety of Human Cancers

Circular RNAs (circRNAs), which act as initiators and promoters of various diseases, were thought to be mostly noncoding RNAs (ncRNAs) in eukaryotes, until recent studies confirmed that some circRNAs have the function of encoding proteins. Accumulating research findings have proved that dysregulation of circRNAs is associated with the developmental process of multiple cancers. circHIPK3, an example of circRNA, is frequently expressed in many diseases, such as diabetes, age-related cataract, idiopathic pulmonary fibrosis, preeclampsia, osteoblasts, and retinal vascular dysfunction, leading to disease development and progression. In addition, circHIPK3 may also serve as a potential biomarker, to help us know more about the rules of occurrence and development of cancers. In recent studies, many circHIPK3-related cancers have been identified, including nasopharyngeal carcinoma, gallbladder cancer, lung cancer, hepatocellular carcinoma, osteosarcoma, glioma, colorectal cancer, ovarian cancer, bladder cancer, prostate cancer, gastric cancer, oral squamous cell carcinoma, and chronic myeloid leukemia. This review summarizes recent studies on the biological mechanisms of circHIPK3 and expounds the molecular mechanisms of circHIPK3 in these malignant tumors.

Opioids and Cancer Mortality

OPINION STATEMENT

Opioids are the gold standard for the treatment of cancer-related pain. Preclinical studies have associated opioids with cancer progression and overall survival. In mice models, opioids have been shown to possess pro-tumor activity secondary to immunosuppression, migration of tumor cells, increased activity of vascular endothelial growth factor receptors, and angiogenesis leading to tumor progression. In contrast, opioids have also been associated with having antitumor activity by activation of apoptosis and phagocytosis. However, high-quality randomized controlled trials in humans that are focused on the association between opioids and survival in cancer patients are lacking, which underscores the importance of being cautious when interpreting the results of the preclinical studies. Cancer-related pain is complex and multifactorial and may worsen as the disease progresses leading to higher opioid utilization. Moreover, cancer pain by itself has been associated with poor survival. The survival in these advanced cancer patients taking opioids may be more likely to be associated with cancer progression and not the opioid use. Adequate treatment of cancer pain has the potential to improve quality of life and performance status, highlighting the importance of continuing to use opioids to manage pain efficiently. More research is clearly needed.

Opioids in Cancer Development, Progression and Metastasis: Focus on Colorectal Cancer

OPINION STATEMENT

So far, opioids have been successfully used to reduce cancer pain in patients in order to improve their quality of life. However, the use of opioids leads to numerous side effects such as constipation, drowsiness, nausea, itching, increased sweating and hormonal changes. In this review, we described the action of opioids in several molecular pathways significant for maintenance of the intestinal homeostasis including the impact on the intestinal epithelium integrity, changes in microbiome composition, modulation of the immune system or induction of apoptosis and inhibition of angiogenesis. We summed up the role of individual opioids in the processes involved in the growth and development of cancer and elucidated if targeting opioid receptors may constitute novel therapeutic option in colon cancer.

Impact of Anesthetics, Analgesics, and Perioperative Blood Transfusion in Pediatric Cancer Patients: A Comprehensive Review of the Literature

Cancer is the leading cause of death by disease in developed countries. Children and adolescents with cancer need surgical interventions (ie, biopsy or major surgery) to diagnose, treat, or palliate their malignancies. Surgery is a period of high vulnerability because it stimulates the release of inflammatory mediators, catecholamines, and angiogenesis activators, which coincides with a period of immunosuppression. Thus, during and after surgery, dormant tumors or micrometastasis (ie, minimal residual disease) can grow and become clinically relevant metastasis. Anesthetics (ie, volatile agents, dexmedetomidine, and ketamine) and analgesics (ie, opioids) may also contribute to the growth of minimal residual disease or disease progression. For instance, volatile anesthetics have been implicated in immunosuppression and direct stimulation of cancer cell survival and proliferation. Contrarily, propofol has shown in vitro anticancer effects. In addition, perioperative blood transfusions are not uncommon in children undergoing cancer surgery. In adults, an association between perioperative blood transfusions and cancer progression has been described for some malignancies. Transfusion-related immunomodulation is one of the mechanisms by which blood transfusions can promote cancer progression. Other mechanisms include inflammation and the infusion of growth factors. In the present review, we discuss different aspects of tumorigenesis, metastasis, angiogenesis, the immune system, and the current studies about the impact of anesthetics, analgesics, and perioperative blood transfusions on pediatric cancer progression.

Morphine contributed to the deterioration of cancer via miR-543/MARCKS/FcγR-mediated phagocytosis pathway

OBJECTIVES

It has been confirmed that morphine was detrimental to patients with cancers. Hence, we aimed to reveal a certain mechanism of morphine in cancer development.

METHODS

Microarray and GSEA analysis were utilized to seek for differently expressed genes and pathway.

KEY FINDINGS

Bioinformatics analysis identified that downregulation of MARCKS and upregulation of miR-543 in samples treated with morphine. FcγR-mediated phagocytosis pathway was illustrated to be upregulated in the control. PANC-1 and DU145 cell viability was increased but apoptosis was declined as morphine concentration went up from 10^-8 to 10^-6  mol/l. On the other curve, the viability was reduced and apoptosis was elevated from 10^-6 to 10^-5  mol/l. The expression of miR-543 ran the same trend as cell viability. Assays in vivo and in vitro validated that miR-543 facilitated cell viability, tumour growth, levels of CA199 and PSA, whereas inhibited apoptosis. MARCKS could target and inhibit miR-543 expression, which exhibited an opposite effect on cancer progression. MiR-543 blocked but MARCKS activated FcγR-mediated phagocytosis pathway.

CONCLUSIONS

Morphine at 10^-6  mol/l could benefit miR-543 expression to inhibit MARCKS expression, consequently, blocking FcγR-mediated phagocytosis pathway, which contributed to the cancer progression in vitro and in vivo.

The dual effect of morphine on tumor development

Morphine is a classic opioid drug used for reducing pain and is commonly prescribed as an effective drug to control cancer pain. Morphine has a direct role in the central nervous system to relieve pain, but because of its peripheral functions, morphine also has some side effects, such as nausea, constipation, and addiction (Gupta et al. in Sci World J 2015:10, 2015). In addition to its analgesic effect, the role of morphine in tumor development is an important question that has been investigated for many years with conflicting results. Numerous studies suggest that morphine has a role in both promoting and inhibiting tumor growth. In this extensive review, we attempt to comprehensively understand the effects of morphine and summarize both its positive and negative influences on various aspects of tumors, including tumor growth, angiogenesis, metastasis, inflammation, and immunomodulation.

CircHIPK3 promotes proliferation and invasion in nasopharyngeal carcinoma by abrogating miR-4288-induced ELF3 inhibition

Circular RNAs (circRNAs) are reported to regulate the development and progression of multiple cancers. However, the functions of circRNAs in nasopharyngeal carcinoma (NPC) are unclear. In this study, we identified that circular homeodomain interacting protein kinase 3 (circHIPK3) was highly expressed in NPC tissues and cell lines. Moreover, we found that circHIPK3 expression levels could act as a prognostic marker in NPC patients. We showed that circHIPK3 silence repressed NPC cell proliferation, migration, and invasion in vitro. In addition, circHIPK3 depletion dramatically repressed tumor growth and metastasis in vivo. Mechanistically, we revealed circHIPK3 as a competing endogenous RNA of microRNA (miR)-4288 that targets E74-like ETS transcription factor 3 (ELF3) in NPC cells. We found that miR-4288 inhibition reversed the effects of circHIPK3 silence on NPC cells. Furthermore, rescue assays also indicated that circHIPK3 promoted the malignant behaviors of NPC cells via enhancing ELF3 expression by suppressing the miR-4288 levels. In conclusion, our findings demonstrated that circHIPK3 facilitated NPC progression through protecting ELF3 from miR-4288-mediated silencing, which suggested that the circHIPK3-miR-4288-ELF3 regulatory loop might be a potential target for NPC prevention.

Wnt6 contributes tumorigenesis and development of colon cancer via its effects on cell proliferation, apoptosis, cell-cycle and migration

Wnt proteins have been reported to contribute to the progression of various types of cancer. Wnt6 is a member of the Wnt family and may promote tumorigenesis in gastrointestinal cancer and cervical cancer. In the present study, the expression of Wnt6 in human colon cancer cell lines was evaluated, in order to investigate the role of Wnt6 in the development of colon cancer. Additionally, the effects of Wnt6 upregulation or downregulation on proliferation, apoptosis, cell cycle and cell migration of colon cancer cells have been investigated. Furthermore, western blot analysis was employed to evaluate the expression of Wnt6, B-cell lymphoma 2-associated X protein (Bax), caspase-3 and matrix metalloproteinase (MMP)2. The results of the present study demonstrated that the expression of Wnt6 was increased in HCT116 and SW480 cells compared with the remaining colon cancer cell lines. Furthermore, overexpression Wnt6 resulting from transfection of pGPU6/GFP/Neo-Wnt6-Homo-1 plasmid promoted the proliferation, cell cycle and migration of HCT116 and SW480 cells, but inhibited cell apoptosis in vitro. The expression of caspase-3 and MMP2 was increased, whereas the expression of Bax was decreased in response to upregulation of Wnt6. These results suggested that Wnt6 may serve a vital function in the development of colon cancer.

Evaluation of the Protective Effect of Olive Leaf Extract on Cisplatin-Induced Testicular Damage in Rats

In the present investigation, the effect of olive leaf extract (OLE) on testicular damage induced in rats by an intraperitoneal injection of cisplatin (cis-diamminedichloroplatinum (CDDP)) at a dose of 5 mg/kg was tested. Rats were randomly divided into 4 groups: control, CDDP, OLE, and OLE + CDDP. After 5 days of CDDP treatment, body and testicular weights, histopathological alteration, and serum male sex hormone levels were determined. In addition to the biochemical and immunohistochemical changes in the testes, CDDP caused the disorganization of germinal epithelium and apoptosis by inducing Bax and inhibiting Bcl-2 protein expression. Testicular weights, catalase, serum testosterone, testicular enzymatic (including glutathione peroxidase, glutathione reductase, and superoxide dismutase) along with nonenzymatic (glutathione) antioxidants, and levels of luteinizing and follicle-stimulating hormones were significantly reduced in addition to a significant increase in testicular malondialdehyde and nitrite/nitrate levels when compared with the control group. OLE treatment markedly attenuated both biochemical and histopathological changes. The reproductive beneficial effects of OLE were mediated, at least partly, by inducing the nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase 1 (HO-1) pathway.

Osthole induces human nasopharyngeal cancer cells apoptosis through Fas-Fas ligand and mitochondrial pathway

Nasopharyngeal carcinoma (NPC) is endemic in Southern China and Southeast Asia. The present study investigated the activity of osthole in suppressing NPC along with the underlying mechanism. Cell growth inhibition was measured using the MTT assay. Apoptosis was detected through 4',6-diamidino-2-phenylindole staining and flow cytometry. Western blotting was used to identify the signaling pathway. Osthole markedly inhibited cell proliferation and induced apoptosis in the NPC cell line. Western blotting results revealed the increased activation of caspases 3, 8, and 9 and poly (ADP-ribose) polymerase. Osthole treatment significantly reduced the expression of the antiapoptotic protein Bcl-2 and increased the expression of the proapoptotic proteins Bax, Bak, BimL, BimS, and t-Bid. Osthole treatment also increased the expression of Fas, FADD, TNF-R1, TNF-R2, DcR2, RIP, and DR5. In addition, osthole treatment significantly increased the expression levels of phosphorylated ERK1/2 and JNK1/2. These results suggested that osthole exerts cytotoxic effects on NPC cell lines mainly through apoptosis mediated by the Fas-Fas ligand and mitochondrial pathway. Osthole could be a potential anticancer agent for NPC.

Upregulation of SOX2-activated lncRNA ANRIL promotes nasopharyngeal carcinoma cell growth

Recent molecularly targeted approaches have gained advances in nasopharyngeal carcinoma treatment. However, the estimated five-year survival rate has not met the desired degree of improvement. Here, we report that upregulation of the expression of the SOX2-activated lncRNA ANRIL is involved in nasopharyngeal carcinoma. ANRIL has been found to be upregulated in clinical nasopharyngeal carcinoma. Using genetic approaches targeting ANRIL in nasopharyngeal carcinoma cells, we found that the knockdown of ANRIL inhibits cell proliferation in vitro and in vivo. Mechanistically, SOX2 binds with ANRIL and increases its RNA level, which upregulates β-catenin signalling, resulting in enhanced nasopharyngeal carcinoma tumourigenesis. Expression levels of ANRIL are positively correlated with SOX2 and β-catenin in clinical nasopharyngeal carcinoma samples. Our findings demonstrate that the SOX2-ANRIL-β-catenin axis plays a critical role in nasopharyngeal carcinoma proliferation and provide a potential therapeutic approach for nasopharyngeal carcinoma patients.

Effects of general anesthesia with or without epidural block on tumor metastasis and mechanisms

The present study aimed to assess whether different anesthesia methods (general anesthesia and general anesthesia combined with epidural block) were associated with tumor metastasis during the perioperative period and the possible molecular mechanisms of tumor metastasis. A rat hepatoma tumor xenograft model was constructed via the subcutaneous injection of Morris hepatoma 3924A cells into the upper axillary fossa. General anesthesia and general anesthesia combined with epidural block prior to hepatectomy were conducted on tumor-bearing rats. The average numbers of metastatic nodules on the lung surface were calculated in the different groups and the presence of abdominal lymph node metastases, rate of malignant ascites and abdominal wall-implanted nodules were recorded. Blood samples were collected from the orbits of rats immediately prior to surgery and at 2, 7 and 30 days following surgery. Plasma levels of interferon-γ, transforming growth factor-α and vascular endothelial growth factor (VEGF) were measured. Finally, the expression of phosphorylated signal transducer and activator of transcription-3 and phosphorylated VEGF were measured by western blot analysis. The results of this analysis demonstrated that tumor metastasis was greatly suppressed when the rats underwent general anesthesia combined with epidural block prior to hepatectomy, compared with general anesthesia alone. The results of cytokine quantification and western blot analysis revealed that the anti-metastatic effect of general anesthesia combined with epidural block may have been mediated by inhibition of STAT3 and the relevant cytokines.

To Treat or Not to Treat: The Effects of Pain on Experimental Parameters

A common dilemma faced by all animal bioethics committees arises when exceptions are proposed to the use of analgesics in painful procedures. The committee and researcher must weigh the possible confounding effects of including additional drugs (analgesics) in their treatment regimen against the moral obligation to perform humane research. Often neglected in these considerations are the potential confounding effects of unrelieved pain and consistency with pain-relieving practices in human medicine. In this review, we summarize what is currently known regarding the molecular and physiologic effects of pain and analgesics in common animal models used across several therapeutic areas. This work is intended to help provide guidance and assurance that a comprehensive approach has been taken when contemplating how pain relief will be applied in animal research protocols.

Down-regulation of the tumour suppressor κ-opioid receptor predicts poor prognosis in hepatocellular carcinoma patients

BACKGROUND

Opioid receptors have become increasingly implicated in cancer progression and long-term patient outcomes. However, the expression and significance of the κ-opioid receptor (KOR) in hepatocellular carcinoma (HCC) remain unclear.

METHODS

In this study, KOR mRNA expression was analysed by real-time quantitative PCR in 64 pairs of HCC tumour tissues and adjacent non-tumour tissues, and KOR protein expression was analysed by immunohistochemistry in 174 HCC patients. We investigated the correlation between KOR expression and clinicopathological parameters to illustrate the potential prognostic significance of KOR expression in HCC.

RESULTS

KOR mRNA expression was significantly down-regulated in 79.69% (51 of 64) of the HCC tumour samples, and KOR expression in tumour tissue was significantly lower than that in adjacent non-tumour tissues (P < 0.001). ROC curve analysis showed that KOR mRNA expression yielded AUC of 0.745, for the detection of HCC patients. Low KOR mRNA expression in HCC was correlated with aggressive clinicopathological parameters, such as tumour size (P = 0.015), differentiation grade (P = 0.011), and TNM stage (P = 0.021). Moreover, down-regulation of KOR protein expression in HCC tissues was detected in 174 HCC patients. Similarly, negative KOR protein expression was significantly correlated with aggressive clinicopathological features, such as tumour size (P = 0.002), vascular invasion (P = 0.003), differentiation grade (P = 0.026), and TNM stage (P = 0.030). Furthermore, Kaplan-Meier survival analysis demonstrated that down-regulation of KOR in HCC indicated poor prognosis. KOR deficiency (KOR^T < N) was correlated to a shorter survival rate and an increased recurrence (both P < 0.001). In univariate and multivariate survival analyses, KOR was identified as a promising independent risk factor for both overall survival (OS, both P < 0.001) and recurrence-free survival (RFS, both P < 0.001).

CONCLUSIONS

Down-regulation of KOR in HCC tumour tissues has a strong association with poor prognosis and KOR might be a potential tumour suppressor.

Tumor response of temozolomide in combination with morphine in a xenograft model of human glioblastoma

Despite multimodal treatments comprising, radiation therapy (RT) and chemotherapy with temozolomide (TMZ), the prognosis of glioblastoma multiforme (GBM) remains dismal and consolidated therapy yields a median survival of 14.6 months.

Blood Brain Barrier (BBB) mediated chemoresistance and high dose related toxicity make necessary the development of new therapeutic approach to sensitize GBM to TMZ.

The aim of the present study was to investigate the potential of the treatment morphine plus TMZ metronmic doses (1,77 and 0,9 mg/kg) in GBM therapy.

The effect of morphine, on tumor cell growth and P-glycoprothein (P-gp) activity, was investigate in in vitro models.

The results demonstrated that GBM cells growth is not influenced by morphine treatment and, for the first time, we show that morphine is an inhibitor of the activity of P-gp efflux transporter who is markedly expressed on BBB.

In vivo, response to the treatments TMZ plus morphine was investigated in an orthotopic nude mice model of GBM.

Animals treated with TMZ metronomic doses showed a significant tumor growth inhibition compared to untreated mice and association with morphine appears to improve TMZ efficacy.

Moreover, the combination of morphine with lower dose of TMZ result in a cytostatic effect on tumor growth over the period of the pharmacological treatments.

In conclusion this novel approach could be a successful strategy to overcome chemoresistance and side effects TMZ mediated, reducing drug dosage and improving long term response, in GBM therapy.

Morphine enhances renal cell carcinoma aggressiveness through promotes survivin level

Background: Morphine is an opioid analgesic drug often used for pain relief in cancer patients. However, there is growing evidence that morphine may modulate tumor growth, progression and metastasis. Unfortunately, the results obtained by these studies are still contradictory.

Methods: In this study, we investigated the effect of morphine in human clear cell renal cell carcinoma 786-O, RLC-310 cells and whether morphine affects on tumor growth in human clear cell renal cell carcinoma 786-O, RLC-310 cells. The cell proliferation was determined by MTT assay, cell proliferation, migration and invasion assays. Immunofluorescence staining and Q-PCR was used to determine the Survivin expression.

Results: It was shown that morphine enhances proliferation of 786-O, RLC-310 cells, whereas morphine promoted the growth and aggressive phenotype of 786-O and RLC-310 cells in vitro though Survivin-dependent signaling.

Conclusions: Our data showed that morphine promotes RCC growth and increases RCC progression via over-expression of Survivin.