Morphine use in cancer surgery

Systemic administration of Resolvin D1 reduces cancer-induced bone pain in mice: Lack of sex dependency in pain development and analgesia

AIMS

Bone cancer produces severe pain that is treated with opioids, but serious side effects limit opioid utilization. There is therefore a need to develop effective and safe non-opioid alternatives. The lipid mediator, Resolvin D1 (RvD1), could be a prospective candidate for cancer pain treatment. To assess RvD1 and other potential candidates, appropriate animal models that recapitulate clinical features must be used. Although several preclinical models of cancer pain have been developed, the influence of sex on the development of cancer pain and the effectiveness of RvD1 have not been studied.

RESULTS

Using a mouse model of fibrosarcoma growth in and around the calcaneus bone, we demonstrated that the mechanical hyperalgesia in the tumor-bearing hind paw develops independently of sex, except that it developed a little sooner in female mice. A single intravenous injection of RvD1 (0.001-10 μg/kg) decreased hyperalgesia in both sexes with similar potency (ED50 = 0.0015 μg/kg) and efficacy. Repeated daily administration of 10 μg/kg RvD1 prolonged the analgesic effect and completely abolished hyperalgesia. This was also independent of sex.

CONCLUSION

In this preclinical mouse model of bone cancer pain, the development of pain and the analgesic effectiveness of RvD1 are not influenced by sex.

Unraveling the protective effects of curcumin against drugs of abuse

Curcumin, a natural compound derived from the turmeric plant (Curcuma longa), has garnered significant attention for its diverse neuroprotective properties. Curcumin has been widely recognized for its remarkable anti-inflammatory, antioxidant, and anti-apoptotic effects, which have shown great potential in the treatment of various disorders, encompassing psychiatric and neurodegenerative diseases. In this review, we delve into the protective effects of curcumin against drugs of abuse, including morphine, methamphetamine, cocaine, nicotine, and alcohol, with a particular focus on the underlying mechanisms from a neuroscience perspective. Overall, curcumin demonstrates promising effects against the neurotoxicity induced by abused drugs through a wide range of mechanisms. These include the modulation of inflammatory cytokines, maintenance of ion homeostasis, epigenetic regulation, enhancement of antioxidant capacity, as well as the activation of the cAMP response element-binding protein (CREB) and brain-derived neurotrophic factor (BDNF) signaling pathways. These findings suggest that curcumin emerges as a promising therapeutic agent in combatting the detrimental effects induced by drugs of abuse, and further research is warranted to fully comprehend the molecular pathways and optimize its utilization for the prevention and treatment of substance abuse-related neurotoxicity.

Anti-Algics in the Therapeutic Response of Breast and Urological Cancers

The effect of anti-algics on tumor progression and the overall survival of patients is controversial and remains unclear. Herein, we disclose the in vitro effects of the local anesthetics lidocaine, ropivacaine, and levobupivacaine on breast (MCF7), prostate (PC3, LNCaP), and bladder (TCCSUP, HT1376) cancer cell lines, both as monotherapy and in combination with standard-of-care therapeutics. Assays for cell proliferation, viability, death profile, and migration were performed. Additionally, we explored the clinical outcomes of opioid use through a cross-sectional study involving 200 metastatic prostate cancer patients. The main clinical data collected included the type of opioid therapy administered, dosage, treatment duration, disease progression, and overall survival. Results obtained demonstrate that treatment with local anesthetics has a promising selective anti-tumor effect on these types of cancer, with higher effects when associated with docetaxel. This points out the use of local anesthetics as an added value in the treatment of prostate carcinoma patients. Alternatively, chronic opioid use was correlated with reduced overall survival (p < 0.05) and progression-free survival (p < 0.05) at each treatment line in the observational study. While these results provide valuable insights, larger prospective studies are imperative to comprehensively evaluate the clinical impact of opioid analgesics in prostate cancer patients.

Pharmacological Modulation of the MIP-1 Family and Their Receptors Reduces Neuropathic Pain Symptoms and Influences Morphine Analgesia: Evidence from a Mouse Model

Neuropathic pain pathophysiology is not fully understood, but it was recently shown that MIP-1 family members (CCL3, CCL4, and CCL9) have strong pronociceptive properties. Our goal was to examine how pharmacological modulation of these chemokines and their receptors (CCR1 and CCR5) influence hypersensitivity after nerve injury in Albino Swiss male mice. The spinal changes in the mRNA/protein levels of the abovementioned chemokines and their receptors were measured using RT-qPCR and ELISA/Western blot techniques in a mouse model of chronic constriction injury of the sciatic nerve. Behavioral studies were performed using the von Frey and cold plate tests after pharmacological treatment with neutralizing antibodies (nAbs) against chemokines or antagonists (CCR1-J113863, CCR5-TAK-220/AZD-5672) alone and in coadministration with morphine on Day 7, when the hypersensitivity was fully developed. Our results showed enhanced protein levels of CCL3 and CCL9 1 and 7 days after nerve injury. The single intrathecal administration of CCL3 or CCL9 nAb, J113863, TAK-220, or AZD-5672 diminished neuropathic pain symptoms and enhanced morphine analgesia. These findings highlight the important roles of CCL3 and CCL9 in neuropathic pain and additionally indicate that these chemokines play essential roles in opioid analgesia. The obtained results suggest CCR1 and CCR5 as new, interesting targets in neuropathy treatment.

Changes in Plasma Metabolic Signature upon Acute and Chronic Morphine Administration in Morphine-Tolerant Mice

Morphine administration causes system-level metabolic changes. Here, we show that morphine-tolerant mice exhibited distinct plasma metabolic signatures upon acute and chronic administration. We utilized a mouse model of morphine tolerance by exposing mice to increasing doses of the drug over 4 days. We collected plasma samples from mice undergoing acute or chronic morphine or saline injections and analyzed them using targeted GC–MS-based metabolomics to profile approximately 80 metabolites involved in the central carbon, amino acid, nucleotide, and lipid metabolism. Our findings reveal distinct alterations in plasma metabolite concentrations in response to acute or chronic morphine intake, and these changes were linked to the development of tolerance to morphine’s analgesic effects. We identified several metabolites that had been differentially affected by acute versus chronic morphine use, suggesting that metabolic changes may be mitigated by prolonged exposure to the drug. Morphine-tolerant mice showed a restoration of amino acid and glycolytic metabolites. Additionally, we conducted reconstructed metabolic network analysis on the first 30 VIP-ranked metabolites from the PLSDA of the saline, acute, and morphine-tolerant mice groups, which uncovered four interaction networks involving the amino acid metabolism, the TCA cycle, the glutamine-phenylalanine-tyrosine pathway, and glycolysis. These pathways were responsible for the metabolic differences observed following distinct morphine administration regimens. Overall, this study provides a valuable resource for future investigations into the role of metabolites in morphine-induced analgesia and associated effects following acute or chronic use in mice.

Influence of opioid analgesia type on circulating tumor cells in open colorectal cancer surgery (POACC-1): study protocol for a prospective randomized multicenter controlled trial

BACKGROUND

Opioids and epidural analgesia are a mainstay of perioperative analgesia but their influence on cancer recurrence remains unclear. Based on retrospective data, we found that cancer recurrence following colorectal cancer surgery correlates with the number of circulating tumor cells (CTCs) in the early postoperative period. Also, morphine- but not piritramide-based postoperative analgesia increases the presence of CTCs and shortens cancer-specific survival. The influence of epidural analgesia on CTCs has not been studied yet.

METHODS

We intend to enroll 120 patients in four centers in this prospective randomized controlled trial. The study protocol has been approved by Ethics Committees in all participating centers. Patients undergoing radical open colorectal cancer surgery are randomized into epidural, morphine, and piritramide groups for perioperative analgesia. The primary outcome is the difference in the number of CTCs in the peripheral blood before surgery, on the second postoperative day, and 2-4 weeks after surgery. The number of CTCs is measured using molecular biology methods. Perioperative care is standardized, and relevant data is recorded. A secondary outcome, if feasible, would be the expression and activity of various receptor subtypes in cancer tissue. We intend to perform a 5-year follow-up with regard to metastasis development.

DISCUSSION

The mode of perioperative analgesia favorably affecting cancer recurrence would decrease morbidity/mortality. To identify such techniques, trials with long-term follow-up periods seem suboptimal. Given complex oncological therapeutic strategies, such trials likely disable the separation of perioperative analgesia effects from other factors. We believe that early postoperative CTCs presence/dynamics may serve as a sensitive marker of various perioperative interventions´ influences on cancer recurrence. Importantly, it is unbiased to the influence of long-term factors and minimally invasive. Analysis of opioid/cannabinoid receptor subtypes in cancer tissue would improve understanding of underlying mechanisms and promote personalization of treatment. We are not aware of any similar ongoing studies.

TRIAL REGISTRATION NUMBER

NCT03700411, registration date: October 3, 2018.

STUDY STATUS

recruiting.

Investigating the Influence of Anaesthesiology for Cancer Resection Surgery on Oncologic Outcomes: The Role of Experimental In Vivo Models

The incidence and societal burden of cancer is increasing globally. Surgery is indicated in the majority of solid tumours, and recent research in the emerging field of onco-anaesthesiology suggests that anaesthetic-analgesic interventions in the perioperative period could potentially influence long-term oncologic outcomes. While prospective, randomised controlled clinical trials are the only research method that can conclusively prove a causal relationship between anaesthetic technique and cancer recurrence, live animal (in vivo) experimental models may more realistically test the biological plausibility of these hypotheses and the mechanisms underpinning them, than limited in vitro modelling. This review outlines the advantages and limitations of available animal models of cancer and how they might be used in perioperative cancer metastasis modelling, including spontaneous or induced tumours, allograft, xenograft, and transgenic tumour models.

Quo Vadis Anesthesiologist? The Value Proposition of Future Anesthesiologists Lies in Preserving or Restoring Presurgical Health after Surgical Insult

This Special Issue of the Journal of Clinical Medicine is devoted to anesthesia and perioperative care [...].

The Potential Effect of Lidocaine, Ropivacaine, Levobupivacaine and Morphine on Breast Cancer Pre-Clinical Models: A Systematic Review

Breast cancer (BC) is one of the most common types of cancer and the second leading cause of death in women. Local anaesthetics (LAs) and opioids have been shown to influence cancer progression and metastasis formation in several pre-clinical studies. However, their effects do not seem to promote consensus. A systematic review was conducted using the databases Medline (via PubMed), Scopus, and Web of Science (2010 to December 2021). Search terms included "lidocaine", "ropivacaine", "levobupivacaine", "morphine", "methadone", "breast cancer", "breast carcinoma" and "breast neoplasms" in diverse combinations. The search yielded a total of 784 abstracts for initial review, 23 of which met the inclusion criteria. Here we summarise recent studies on the effect of analgesics and LAs on BC cell lines and animal models and in combination with other treatment regimens. The results suggest that local anaesthetics have anti-tumorigenic properties, hence their clinical application holds therapeutic potential. Regarding morphine, the findings are conflicting, but this opioid appears to be a tumour-promoting agent. Methadone-related results are scarce. Additional research is clearly required to further study the mechanisms underlying the controversial effects of each analgesic or LA to establish the implications upon the outcome and prognosis of BC patients' treatment.

Melatonin attenuates morphine-induced conditioned place preference in Wistar rats

PURPOSE

Morphine is the predominantly used drug for postoperative and cancer pain management. However, the abuse potential of morphine is the primary disadvantage of using opioids in pain management. Melatonin is a neurohormone synthesized in the pineal gland and is involved in circadian rhythms in mammals, as well as other physiological functions. Melatonin provenly attenuates alcohol-seeking and relapse behaviors in rats. Therefore, we aimed to investigate the involvement of the melatonergic system in attenuating morphine dependence.

MATERIALS AND METHODS

Male Wistar rats were divided into three groups: control, morphine, and morphine + melatonin. Animals were habituated for 3 days, and the initial preference was evaluated. Following the initial preference, the control group received the vehicle and was placed for a 45-min session in the assigned chamber every day, alternating between the two chambers, for 8 days. The morphine group received a morphine injection (5 mg/kg, IP) and was placed for a 45-min session in the white chamber, for a total of four sessions. The morphine + melatonin group received the morphine injection (5 mg/kg, IP) for a total of four sessions over an 8-day period. In the posttest session, the control and morphine groups received a vehicle injection 30 min before placement in the conditioned place preference (CPP). The morphine + melatonin group received a single injection of melatonin (50 mg/kg, IP) 30 min before the preference test.

RESULTS

Statistical analysis revealed that repeated administration of morphine for four sessions produced a significant increase in the CPP score in the morphine group compared to the control group. However, a single melatonin injection administered 30 min before the posttest attenuated morphine-seeking behavior and reduced morphine-induced place preference.

CONCLUSION

These findings provide novel evidence for the role of the melatonergic system as a potential target in modulating morphine-seeking behavior.

Opioids and matrix metalloproteinases: the influence of morphine on MMP-9 production and cancer progression

Opioids are widely administered to alleviate pain, including chronic pain in advanced cancer patients. Among opioids, morphine is one of the most clinically effective drugs for the palliative management of severe pain. In the last few decades, there has been a debate around the possible influence of opioids such as morphine on tumour growth and metastasis. Whilst several in vitro and in vivo studies suggest the possible modulatory effects of morphine on tumour cells, little is known about the impact of this analgesic drug on other mediators such as matrix metalloproteinases (MMPs) that play a key role in the control of cancer cell invasion and metastasis. MMP-9 has been considered as one of the principal mediators in regulation of not only the initial steps of cancer but during the invasion and spreading of cancer cells to distant organs. Herein, current studies regarding the direct and indirect effects of morphine on regulation of MMP-9 production are discussed. In addition, drawing from previous in vivo and in vitro studies on morphine action in regulating MMP-9 production, the potential roles of several underlying factors are summarised, including nuclear factor kappa-B and intracellular molecules such as nitric oxide.

Interfascial block at the serratus muscle plane versus conventional analgesia in breast surgery: a randomized controlled trial

Background and objectives

In the context of opioid-sparing perioperative management, there is still little evidence from randomized controlled trials regarding the effectiveness of interfascial thoracic blocks. This study hypothesizes that receiving a serratus plane block reduces opioid requirements, pain scores, and rescue medication needs.

Methods

This double-blind, randomized controlled study was conducted on 60 adult females undergoing oncologic breast surgery. After general anesthesia, patients were randomly allocated to either conventional analgesia (control group, n=30) or single-injection serratus block with L-bupivacaine 0.25% 30mL (study group, n=30). First 24-hour total morphine consumption (primary outcome), pain scores at 1, 3, 6, 12, and 24 hours, time-to-first opioid rescue analgesia, and adverse effects were recorded.

Results

Median 24 hours’ opioid dose was greater in the control group (median difference 9 mg (95% CI 4 to 14.5 mg); p<0.001). Proportional odds model showed that the study group has a lower probability of receiving opioid drugs (OR=0.26 (95% CI 0.10 to 0.68); p<0.001), while mastectomies have a higher probability of receiving them (OR=4.11 (95% CI 1.25 to 13.58); p=0.002). Pain scores in the study group were significantly lower throughout the follow-up period (p<0.001). Control group subjects needed earlier morphine rescue and had a higher risk of rescue dose requirement (p=0.002).

Conclusions

Interfascial serratus plane block reduces opioid requirements and is associated with better pain scores and lower and later rescue analgesia needs in the first 24 hours, compared with conventional intravenous analgesia, in breast surgery.

Trial registration number

NCT02905149.

Morphine alters the circulating proteolytic profile in mice: functional consequences on cellular migration and invasion

Opioids modulate the tumor microenvironment with potential functional consequences for tumor growth and metastasis. We evaluated the effects of morphine administration on the circulating proteolytic profile of tumor-free mice. Serum from morphine-treated (1 or 10 mg/kg, i.p. every 12 h) or saline-treated mice was collected at different time points and tested ex vivo in endothelial, lymphatic endothelial, and breast cancer cell migration assays. Serum from mice that were treated with 10 mg/kg morphine for 3 d displayed reduced chemotactic potential for endothelial and breast cancer cells, and elicited reduced cancer cell invasion through reconstituted basement membrane compared with serum from saline controls. This was associated with decreased circulating matrix metalloproteinase 9 (MMP-9) and increased circulating tissue inhibitor of metalloproteinase 1 (TIMP-1) and TIMP-3/4 as assessed by zymography and reverse zymography. By using quantitative RT-PCR, we confirmed morphine-induced alterations in MMP-9 and TIMP expression and identified organs, including the liver and spleen, in which these changes originated. Pharmacologic inhibition of MMP-9 abrogated the difference in chemotactic attraction between serum from saline-treated and morphine-treated mice, which indicated that reduced proteolytic ability mediated the decreased migration toward serum from morphine-treated mice. This novel mechanism may enable morphine administration to promote an environment that is less conducive to tumor growth, invasion, and metastasis.-Xie, N., Khabbazi, S., Nassar, Z. D., Gregory, K., Vithanage, T., Anand-Apte, B., Cabot, P. J., Sturgess, D., Shaw, P. N., Parat, M.-O. Morphine alters the circulating proteolytic profile in mice: functional consequences on cellular migration and invasion.

Three -Agent Preemptive Analgesia, Pregabalin-Acetaminophen-Naproxen, in Laparotomy for Cancer: A Randomized Clinical Trial

Background

Pain management after abdominal surgery is a critical issue in cancer patients undergoing laparotomy. Opioid analgesics commonly used postoperatively have significant side effects and can postpone restoring normal life. Administration of analgesics before the surgery by inhibiting pain cascades may be an effective method for more efficient pain control.

Objectives

This study aimed to investigate the effect of the preemptive use of oral pregabalin-acetaminophen-naproxen on pain control and morphine consumptions in cancer patients undergoing laparotomy.

Patients and Methods

A total of 40 cancer patients scheduled for open abdominal surgery were randomized into the two groups. one group received combination of pregabalin 150 mg, acetaminophen 1 g and naproxen 250 mg (the PAN group) an hour before laparotomy. Following the surgery, morphine was administered on a protocolized schedule based on patients’ demand for pain control. Postoperative pain level was assessed using universal pain assessment tool (UPAT) at 0, 2, 4, 6, 12, 24 and 48 hours after the operation. The postoperative morphine dose and complications were noted. Data were analyzed using SPSS version 16.

Results

Patients in the PAN group had significantly lower UPAT scores at 0, 2, 4, 6, 12, 24 and 48 hours after the surgery than those in the control group (P = 0.008, 0.021, 0.008, 0.047, 0.004, 0.001, and 0.001). The mean dose of postoperative morphine consumption in the PAN group was 37% less than the control group (P = 0.001). The complications were not significantly different between the two groups.

Conclusions

Preemptive use of pregabalin-acetaminophen-naproxen decreases intensity of pain and morphine consumption in the cancer patients after laparotomy without significant complications.

Morphine Modulates Interleukin-4- or Breast Cancer Cell-induced Pro-metastatic Activation of Macrophages

Interactions between cancer cells and stromal cells in the tumour microenvironment play a key role in the control of invasiveness, metastasis and angiogenesis. Macrophages display a range of activation states in specific pathological contexts and alternatively activated (M2) macrophages can promote tumour aggressiveness. Opioids are able to modulate tumour growth and metastasis. We tested whether morphine modulates the activation of macrophages induced by (i) interleukin-4 (IL-4), the prototypical M2 polarization-inducing cytokine, or (ii) coculture with breast cancer cells. We showed that IL-4 causes increased MMP-9 production and expression of the alternative activation markers arginase-1 and MRC-1. Morphine prevented IL-4-induced increase in MMP-9 in a naloxone- and methylnaltrexone-reversible fashion. Morphine also prevented IL-4-elicited alternative activation of RAW264.7 macrophages. Expression of MMP-9 and arginase-1 were increased when RAW264.7 were subjected to paracrine activation by 4T1 cells, and this effect was prevented by morphine via an opioid receptor-mediated mechanism. Morphine further decreased 4T1 breast cancer cell invasion elicited by co-culture with RAW264.7. Reduction of MMP-9 expression and alternative activation of macrophages by morphine was confirmed using mouse bone marrow-derived macrophages. Taken together, our results indicate that morphine may modulate tumour aggressiveness by regulating macrophage protease production and M2 polarization within the tumour microenvironment.

[Pain therapy in emergency medicine. Focus on emergency admissions]

With a prevalence of 50-80 % pain is one of the main symptoms of emergency admission patients worldwide; however, study results demonstrate that only 30-50 % of patients receive adequate analgesia. Therefore, in the USA quality indicators have been established by the Centers for Medicare & Medicaid Services (CMS) since 2010 within the framework of quality assurance of emergency admissions, e.g. the time window until the start of pain therapy. Despite the prescribed pain evaluation as part of many existing triage systems, e.g. the Manchester triage system (MTS), emergency severity index (ESI), Australasian triage scale (ATS), Canadian triage and acuity scale (CATS), in most emergency rooms there is no standardized, documented pain assessment and pain intensity is documented by using the appropriate pain scales in only 30 % of cases. Lack of knowledge and training and lack of awareness by the nursing and medical staff regarding pain perception and management represent the main causal factors. Studies on the situation of pain therapy in German emergency departments are not currently available. Due to the increasing number of central emergency departments and interdisciplinary teams of physicians and nurses, it seems sensible to introduce interdisciplinary standards of treatment to achieve the greatest possible safety in the use of analgesics in the emergency room. It is important to incorporate the experiences of the various clinical departments in the standards. This article aims to provide an overview of the situation in pain management in emergency departments and to serve as a basis for recommendations for pain therapy in German emergency departments. This article particularly discusses the possibilities of pain evaluation, treatment options with various medications and under specific conditions, e.g. for children, pregnant women or the elderly or alternative ways of pain management.

Comparison and analysis of the animal models used to study the effect of morphine on tumour growth and metastasis

The effect of opioids on tumour growth and metastasis has been debated for many years, with recent emphasis on the possibility that they might influence the rate of disease-free survival after tumour resection when used in the perioperative pain management of cancer surgery patients. The literature presents conflicting and inconclusive in vitro and in vivo data about the potential effect of opioids, especially morphine, on tumour growth and metastasis. To inform clinical practice, appropriate animal models are needed to test whether opioids alter the course of tumour growth and metastasis. Here, we review the literature on animal-based studies testing the effect of morphine on cancer so far, and analyse differences between the models used that may explain the discrepancies in published results. Such analysis should elucidate the role of opioids in cancer and help define ideal pre-clinical models to provide definitive answers.

LINKED ARTICLES

This article is part of a themed section on Opioids: New Pathways to Functional Selectivity. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-2.

Increased μ-opioid receptor expression in metastatic lung cancer

BACKGROUND

We and others have previously demonstrated that the μ-opioid receptor (MOR) is overexpressed in several human malignancies. There is a seven-fold increase in MOR in cell lines of human lung cancer. In animal models, overexpression of MOR promotes tumour growth and metastasis. We, therefore, examined whether MOR expression is increased in metastatic lung cancer.

METHODS

In this study, we examined the association between MOR expression and metastasis in archived biopsy samples from patients with lung cancer. Paraffin-embedded patient material was stained using MOR antibody and scored qualitatively by two independent pathologists using a four-point scale.

RESULTS

In human lung cancer and normal adjacent lung samples obtained from 34 lung cancer patients, MOR expression was increased significantly in cancer samples from patients with lung cancer compared with adjacent control tissue (P=0.0242). When the samples from patients with metastatic lung cancer were separated from the cohort of the total number of patients with lung cancer, we observed an approximately two-fold increase in MOR expression (P=0.0013).

CONCLUSIONS

The association between the expression of MOR and the progression of the tumour is consistent with the hypothesis of a direct effect of MOR on cancer progression.

The Mu opioid receptor promotes opioid and growth factor-induced proliferation, migration and Epithelial Mesenchymal Transition (EMT) in human lung cancer

Recent epidemiologic studies implying differences in cancer recurrence based on anesthetic regimens raise the possibility that the mu opioid receptor (MOR) can influence cancer progression. Based on our previous observations that overexpression of MOR in human non-small cell lung cancer (NSCLC) cells increased tumor growth and metastasis, this study examined whether MOR regulates growth factor receptor signaling and epithelial mesenchymal transition (EMT) in human NSCLC cells. We utilized specific siRNA, shRNA, chemical inhibitors and overexpression vectors in human H358 NSCLC cells that were either untreated or treated with various concentrations of DAMGO, morphine, fentanyl, EGF or IGF. Cell function assays, immunoblot and immunoprecipitation assays were then performed. Our results indicate MOR regulates opioid and growth factor-induced EGF receptor signaling (Src, Gab-1, PI3K, Akt and STAT3 activation) which is crucial for consequent human NSCLC cell proliferation and migration. In addition, human NSCLC cells treated with opioids, growth factors or MOR overexpression exhibited an increase in snail, slug and vimentin and decrease ZO-1 and claudin-1 protein levels, results consistent with an EMT phenotype. Further, these effects were reversed with silencing (shRNA) or chemical inhibition of MOR, Src, Gab-1, PI3K, Akt and STAT3 (p<0.05). Our data suggest a possible direct effect of MOR on opioid and growth factor-signaling and consequent proliferation, migration and EMT transition during lung cancer progression. Such an effect provides a plausible explanation for the epidemiologic findings.

Effect of opiates, anesthetic techniques, and other perioperative factors on surgical cancer patients

BACKGROUND

Opioid pharmacotherapy is often used to treat cancer pain. However, morphine and other opioid-like substance use in patients with cancer may have significant adverse consequences, including the suppression of both innate and acquired immune responses. Although studies have examined the possibility that regional anesthesia attenuates the immunosuppressive response of surgery, the effects of morphine and other opioid-related substances on tumor progression remain unknown.

METHODS

This article presents an evidence-based review of the influence of opioids and anesthetic technique on the immune system in the context of cancer recurrence. The review focuses on the field of regional anesthesia and the setting of surgical oncologic procedures. The method for perioperative pain management and the technique of anesthesia chosen for patients in cancer surgery were explored.

RESULTS

General anesthetics have been indicated to suppress both cell-mediated immunity and humoral immunity. Evidence suggests that intravenous opioids suppress the immune system. However, the mechanisms by which anesthetics and analgesics inhibit the immune system are not understood. Compared with the alternatives, regional analgesia offers reduced blood loss and superior postoperative analgesia. Because of these advantages, the use of regional analgesia has increased in oncologic surgeries.

CONCLUSION

Immune responses from all components of the immune system, including both the humoral and cell-mediated components, appear to be suppressed by anesthetics and analgesics. The clinical anesthesiologist should consider these factors in the application of technique, especially in cancer surgery.

Does regional anaesthesia and analgesia or opioid analgesia influence recurrence after primary cancer surgery? An update of available evidence

Cancer continues to be a key cause of morbidity and mortality worldwide and its overall incidence continues to increase. Anaesthetists are increasingly faced with the challenge of managing cancer patients, for surgical resection to debulk or excise the primary tumour, or for surgical emergencies in patients on chemotherapy or for the analgesic management of disease- or treatment-related chronic pain. Metastatic recurrence is a concern. Surgery and a number of perioperative factors are suspected to accelerate tumour growth and potentially increase the risk of metastatic recurrence. Retrospective analyses have suggested an association between anaesthetic technique and cancer outcomes, and anaesthetists have sought to ameliorate the consequences of surgical trauma and minimise the impact of anaesthetic interventions. Just how anaesthesia and analgesia impact cancer recurrence and consequent survival is very topical, as understanding the potential mechanisms and interactions has an impact on the anaesthetist's ability to contribute to the successful outcome of oncological interventions. The outcome of ongoing, prospective, randomized trials are awaited with interest.

Morphine improved the antitumor effects on MCF-7 cells in combination with 5-Fluorouracil

BACKGROUND

The most frequently used opioid in cancer pain management is morphine which remains a cornerstone for the management of cancer pain, due to the largest experience existing among physicians and widely availability in a variety of formulation. Considering that analgesics on cancer pain is often under the condition of chemotherapy and 5-Fluorouracil (5-FU) is widely used today as a potent drug for the treatment of advanced cancers, whether analgesics such as morphine, interferes the chemotherapy such as 5-FU, arose as a considerable problem.

METHODS

In this study, the MCF-7 breast cancer cells were used to determine the antitumor effects of the 5-FU in combination with morphine. The cell proliferation was determined by the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay and the apoptosis was determined by the Annexin V/PI staining and flow cytometry. The immunocytochemistry and western blot was used to determine the Bcl-2 and Bax expression.

RESULTS

It was shown that in MCF-7 cells, the proliferation was inhibited, the apoptosis was promoted, the Bcl-2 expression was suppressed and the Bax expression was promoted by both 5-FU alone and morphine alone, while the superior effects were achieved in combination with the two drugs.

CONCLUSION

These results suggest that the morphine may have the beneficial effects on the antitumor chemotherapy with 5-FU, in stead of interferential effects.

Anaesthetic agents for thoracic surgery: what's best?

PURPOSE OF REVIEW

Pneumonectomy is still associated with a 5% 30-day mortality in a large series involving a variety of anaesthetic agents and techniques.

RECENT FINDINGS

As well as the immediate 'anaesthetic' complications of pain, nausea and vomiting and respiratory dysfunction, differences between anaesthetic agents have emerged in systemic inflammation, postoperative cognitive dysfunction, immune suppression and cell signalling after surgery.

SUMMARY

No one anaesthetic agent has emerged as best. There is a trade-off between initial success and long-term problems or vice versa.

Can anaesthetic and analgesic techniques affect cancer recurrence or metastasis?

Cancer is a leading cause of morbidity and mortality worldwide and the ratio of incidence is increasing. Mortality usually results from recurrence or metastases. Surgical removal of the primary tumour is the mainstay of treatment, but this is associated with inadvertent dispersal of neoplastic cells into the blood and lymphatic systems. The fate of the dispersed cells depends on the balance of perioperative factors promoting tumour survival and growth (including surgery per se, many anaesthetics per se, acute postoperative pain, and opioid analgesics) together with the perioperative immune status of the patient. Available evidence from experimental cell culture and live animal data on these factors are summarized, together with clinical evidence from retrospective studies. Taken together, current data are sufficient only to generate a hypothesis that an anaesthetic technique during primary cancer surgery could affect recurrence or metastases, but a causal link can only be proved by prospective, randomized, clinical trials. Many are ongoing, but definitive results might not emerge for a further 5 yr or longer. Meanwhile, there is no hard evidence to support altering anaesthetic technique in cancer patients, pending the outcome of the ongoing clinical trials.