Drugs of anaesthesia and cancer

Effect of regional anesthesia and analgesia on long-term survival following abdominal cancer Surgery-A systematic review with meta-analysis

Background

The impact of regional anesthesia and analgesia (RAA) on long-term survival following cancer surgery is a topic of debate. The aim of this study was to investigate the effects of perioperative RAA on long-term oncological outcomes in patients undergoing major abdominal cancer surgery.

Methods

The authors searched computerized databases and reference lists from inception to December 20, 2022. All studies that investigated the effects of perioperative RAA on long-term oncological outcomes following major abdominal cancer surgery were included. Using the inverse variance method with a random-effects model, hazard ratios (HR) and 95% confidence intervals (CI) were calculated.

Results

The systematic review included 51 retrospective studies, one prospective study, and three randomized controlled trials (RCTs), with a total of 95,046 patients. The results showed that perioperative RAA may improve long-term overall survival (HR: 0.85, 95% CI: 0.80 to 0.91, P = 0.00, I2 = 60.2%). However, there was no significant association between perioperative RAA and reduced cancer recurrence (HR: 0.98, 95% CI: 0.90 to 1.03, P = 0.31, I2 = 52.3%). When performing a pooled analysis of the data from the three RCTs, no statistically significant effect of RAA was found in either case.

Conclusion

The systematic review suggests perioperative RAA may improve long-term overall survival but does not appear to reduce cancer recurrence in patients undergoing major abdominal cancer surgery. The limited number of RCTs included in this study did not confirm this finding, highlighting the need for further RCTs to corroborate these results.

Impact of propofol versus sevoflurane anesthesia on molecular subtypes and immune checkpoints of glioma during surgery

Background

Sevoflurane and propofol are two popular anesthetics used during glioblastoma (GBM) surgery. This investigation compared the molecular subtypes and immune checkpoints of cancer cells following GBM surgery under sevoflurane and propofol anesthesia.

Method

The expression profile data and clinical information of glioma samples of different grades were downloaded from The Cancer Genome Atlas database. Weighted gene coexpression network analysis was used to identify hub modules and key genes related to glioma grades (G2 and G3). The GEO database (GSE179004) was used to retrieve glioma surgical specimens with different anesthetic gene expression profiles. The differential expression of immune checkpoint genes under various anesthetic settings was examined using the R-ggplot2.

Results

Compared to sevoflurane, propofol significantly downregulated SERPINI1 and CAMK2A expression. These are also important factors in glioma grading. Simultaneously, SERPINI1 and CAMK2A were also significantly related to the prognosis of GBM and lower-grade glioma patients and acted as potential tumor suppressors. In addition, propofol increases the expression of the immune checkpoint molecule, PD-L1.

Conclusions

Our study revealed that sevoflurane can more effectively prevent the development of glioma after surgery than propofol, and SERPINI1 can be used as a new independent prognostic factor for glioma.

Parameters of Metabolic Response to Surgical Trauma Induced via Unilateral Total Mastectomy Associated or Not to Ovariohysterectomy in Dogs

Surgical excision of solid tumors is required for local control of neoplasms. However, surgical trauma can stimulate the release of proangiogenic growth factors, suppressing cell-mediated immunity and favoring the development of micrometastases and progression of residual disease. The present study aimed to evaluate the intensity of the metabolic response to trauma induced via unilateral mastectomy in bitches with mammary neoplasia, the consequences of its joint performance with ovariohysterectomy, and their respective effects on the organic response. Two groups of animals were evaluated in seven perioperative moments, namely, unilateral mastectomy (G1) and unilateral mastectomy associated with ovariohysterectomy (G2). Thirty-two female dogs were selected, ten clinically healthy, and twenty-two diagnosed with mammary neoplasia. Surgical trauma reduced serum concentrations of albumin and interleukin-2 but increased blood levels of glucose and interleukin-6 in the postoperative of G1 and G2 patients. Moreover, serum cortisol levels increased after unilateral mastectomy associated with ovariohysterectomy. Our findings allowed us to conclude that unilateral mastectomy induces significant metabolic alterations in female dogs with mammary neoplasms and its joint performance with ovariohysterectomy increases the organic response to trauma.

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.

Crosstalk between Mu-Opioid receptors and neuroinflammation: Consequences for drug addiction and pain

Mu-Opioid Receptors (MORs) are well-known for participating in analgesia, sedation, drug addiction, and other physiological functions. Although MORs have been related to neuroinflammation their biological mechanism remains unclear. It is suggested that MORs work alongside Toll-Like Receptors to enhance the release of pro-inflammatory mediators and cytokines during pathological conditions. Some cytokines, including TNF-α, IL-1β and IL-6, have been postulated to regulate MORs levels by both avoiding MOR recycling and enhancing its production. In addition, Neurokinin-1 Receptor, also affected during neuroinflammation, could be regulating MOR trafficking. Therefore, inflammation in the central nervous system seems to be associated with altered/increased MORs expression, which might regulate harmful processes, such as drug addiction and pain. Here, we provide a critical evaluation on MORs' role during neuroinflammation and its implication for these conditions. Understanding MORs' functioning, their regulation and implications on drug addiction and pain may help elucidate their potential therapeutic use against these pathological conditions and associated disorders.

A 20-Year Research Trend Analysis of the Influence of Anesthesia on Tumor Prognosis Using Bibliometric Methods

Background

Bibliometric analysis is used to gain a systematic understanding of developments in the field of the influence of anesthesia on tumor prognosis and changes in research hot spots over the past 20 years.

Methods

Relevant publications from the Web of Science Core Collection (WoSCC) were downloaded on May 5, 2021. Acquired data were then analyzed using the Online Analysis Platform of Literature Metrology (http://biblimetric.com) and the CiteSpace software was used to analyze and predict trends and hot spots in this field.

Results

1,521 publications on the influence of anesthesia on tumor prognosis were identified and 1494 qualifying records were included in the final analysis. The leading country in this field was the United States of America (USA). The University of Texas MD Anderson Cancer Center (Houston, TX, USA) and Pennsylvania State University (State College, PA, USA) featured the highest number of publications among all institutions. Co-citation cluster labels revealed characteristics of ten main clusters: total intravenous anesthesia, opioid growth factor receptor, gastric cancer cell, opioid receptor, murine model, natural killer cell activity, health-related quality, glioma cell, opioid switching and mu-type opioid receptor. Keyword burst detection indicated that randomized controlled trials (RCTs), volatile anesthetics, and ropivacaine were the newly emerging research hot spots.

Conclusions

This study compiled 1494 publications covering anesthesia and tumor prognosis research and showed that the direction of these studies is likely in transition from opioids and their receptors to other anesthetics, and from retrospective studies to prospective randomized controlled trials. It provides guidance for further research and clinical applications on choosing anesthetic methods and drugs.

Local anesthetics impair the growth and self-renewal of glioblastoma stem cells by inhibiting ZDHHC15-mediated GP130 palmitoylation

BACKGROUND

A large number of preclinical studies have shown that local anesthetics have a direct inhibitory effect on tumor biological activities, including cell survival, proliferation, migration, and invasion. There are few studies on the role of local anesthetics in cancer stem cells. This study aimed to determine the possible role of local anesthetics in glioblastoma stem cell (GSC) self-renewal and the underlying molecular mechanisms.

METHODS

The effects of local anesthetics in GSCs were investigated through in vitro and in vivo assays (i.e., Cell Counting Kit 8, spheroidal formation assay, double immunofluorescence, western blot, and xenograft model). The acyl-biotin exchange method (ABE) assay was identified proteins that are S-acylated by zinc finger Asp-His-His-Cys-type palmitoyltransferase 15 (ZDHHC15). Western blot, co-immunoprecipitation, and liquid chromatograph mass spectrometer-mass spectrometry assays were used to explore the mechanisms of ZDHHC15 in effects of local anesthetics in GSCs.

RESULTS

In this study, we identified a novel mechanism through which local anesthetics can damage the malignant phenotype of glioma. We found that local anesthetics prilocaine, lidocaine, procaine, and ropivacaine can impair the survival and self-renewal of GSCs, especially the classic glioblastoma subtype. These findings suggest that local anesthetics may weaken ZDHHC15 transcripts and decrease GP130 palmitoylation levels and membrane localization, thus inhibiting the activation of IL-6/STAT3 signaling.

CONCLUSIONS

In conclusion, our work emphasizes that ZDHHC15 is a candidate therapeutic target, and local anesthetics are potential therapeutic options for glioblastoma.

Effects of cisatracurium on epithelial-to-mesenchymal transition in esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) is one of the most aggressive types of cancer worldwide, with a poor prognosis. The aim of the present study was to investigate the effect of cisatracurium (Cis) on epithelial-to-mesenchymal transition (EMT) in ESCC and its potential mechanism of action. In the present study, Cis was used to treat ECA-109 cells, with cell proliferation measured by a Cell Counting Kit-8 assay and the expression of TGF-β and phospho-Smad2/3 detected by western blotting. TGF-β was then applied to induce EMT. Flow cytometry, wound healing and Transwell assays were used to evaluate cell proliferation, apoptosis, invasion and migration. In addition, cell cycle-related proteins, including cyclin D1, p53 and p21, and EMT-associated proteins, including E-cadherin (E-cad), N-cadherin (N-cad), Vimentin and Slug, were examined by western blot analysis. The results revealed that Cis inhibited the proliferation and promoted apoptosis of ESCC cells. Following treatment with Cis, the expression of TGF-β and phosphorylation of Smad2/3 were downregulated. Cis also suppressed cancer cell invasion and migration induced by TGF-β. In addition, the expression levels of cyclin D1 were decreased, accompanied by increased p53 and p21 expression. In addition, the expression level of E-cad was increased, whereas N-cad, Vimentin and Slug were significantly reduced. Taken together, the results of the present study revealed that exposure of ESCC cells to Cis inhibited EMT and reduced cell invasion and metastasis through the TGF-β/Smad signaling pathway.

Fentanyl inhibits proliferation and invasion via enhancing miR-302b expression in esophageal squamous cell carcinoma

Fentanyl is one of the most commonly used intravenous anesthetic agents during cancer resection surgery, but the effect of fentanyl on esophageal squamous cell carcinoma (ESCC) remains unclear. The aim of the present study was to investigate the involvement of microRNA 302b (miR-302b) in the anti-proliferation and anti-invasion effects of fentanyl in ESCC. In the present study, the effects of fentanyl on cell proliferation, apoptosis and invasion were detected using MTT assays, flow cytometry and Transwell assays in ESCC Eca109 and TE1 cell lines. Subsequently, expression of miR-302b was determined using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). RT-qPCR and western blot analysis were performed in order to evaluate the expression of ErbB4, a target of miR-302b. Furthermore, anti-miR were used to inhibit miR-302b in fentanyl-treated ESCC cells in order to evaluate the role of miR-302b in the effect of fentanyl on malignant behaviors. Fentanyl inhibited the proliferation of Eca109 and TE1 cells in a dose- and time-dependent manner. Following exposure to fentanyl for 48 h, Eca109 and TE1 cells exhibited increased apoptosis and decreased invasion. Furthermore, fentanyl upregulated miR-302b expression, but downregulated ErbB4 expression. Finally, loss of miR-302b using the anti-miR technique reversed the effect of fentanyl on cell proliferation, apoptosis and invasion in the two ESCC cell lines. Taken together, the results of the present study indicated that fentanyl inhibits the proliferation and invasion of ESCC cells through upregulation of miR-302b.

Mechanical ventilation promotes lung metastasis in experimental 4T1 breast cancer lung-metastasized models

BACKGROUND/PURPOSE

The aim of this study was to test the hypothesis that mechanical ventilation (MV) during cancer surgery induces lung stroma/tissue milieu changes, creating a favorable microenvironment for postoperative lung metastatic tumor establishment.

MATERIALS AND METHODS

In Protocol A, female BALB/c mice were divided into an MV group and a control (no MV) group, both of which were anesthetized and subjected to intravenous injection of green fluorescent protein (GFP)-labeled mouse mammary carcinoma cell line (4T1) cells. After 24 h, the lung tissue was removed and the number of GFP-labeled 4T1 cells was calculated. In Protocol B, the clinically relevant mouse model of spontaneous breast cancer lung metastasis was used with surgical resection of the primary tumor to investigate the MV event that dictates postoperative lung metastasis. Female BALB/c mice were inoculated in the mammary fat pad with 4T1 cells. After 14-d growth, mice were anesthetized and divided into an MV group and a control (no MV) group during surgical procedures (mastectomy). Metastatic tumor burden was assessed two weeks after mastectomy by both macroscopic metastatic nodule count, hematoxylin-eosin histology, immunohistochemistry for the macrophage marker (CD68), and epithelial cell adhesion molecule (EpCAM).

RESULTS

MV was associated with a significant increase in the number of circulating breast tumor cells (GFP-labeled 4T1 cells) remaining in the microvasculature of the lung (P<0.01). Immunohistochemical results showed increased infiltration of CD68-positive macrophages within injured lung parenchyma and metastatic tumor as well as increased expression of EpCAM in metastatic nodules. Postoperative metastases were more prevalent in the mechanically ventilated mice group compared to the non-ventilated group (P<0.05).

CONCLUSION

MV-induced lung metastasis occurs by attracting circulating tumor cells to the site of the lung injury and by accelerating the proliferation of preexisting micro-metastases in the lung. These observations indicate that the metastasis-enhancing effect of MV should be considered in general anesthesia during cancer surgery.

Perioperative Anesthesia Care and Tumor Progression

This narrative review discusses the most recent up-to-date findings focused on the currently available "best clinical practice" regarding perioperative anesthesia care bundle factors and their effect on tumor progression. The main objective is to critically appraise the current literature on local anesthetics, regional outcome studies, opioids, and nonsteroidal anti-inflammatory drugs (NSAIDs) and their ability to decrease recurrence in patients undergoing cancer surgery. A brief discussion of additional topical perioperative factors relevant to the anesthesiologist including volatile and intravenous anesthetics, perioperative stress and anxiety, nutrition, and immune stimulation is included. The results of several recently published systematic reviews looking at the association between cancer recurrences and regional anesthesia have yielded inconclusive data and provide insufficient evidence regarding a definitive benefit of regional anesthesia. Basic science data suggests an anti tumor effect induced by local anesthetics. New refined animal models show that opioids can safely be used for perioperative pain management. Preliminary evidence suggests that NSAIDs should be an essential part of multimodal analgesia. Volatile anesthetics have been shown to increase tumor formation, whereas preclinical and emerging clinical data from propofol indicate tumor protective qualities. The perioperative period in the cancer patient represents a unique environment where surgically mediated stress response leads to immune suppression. Regional anesthesia techniques when indicated in combination with multimodal analgesia that include NSAIDs, opioids, and local anesthetics to prevent the pathophysiologic effects of pain and neuroendocrine stress response should be viewed as an essential part of balanced anesthesia.

Effect of propofol on androgen receptor activity in prostate cancer cells

Androgen receptor is a nuclear receptor and transcription factor activated by androgenic hormones. Androgen receptor activity plays a pivotal role in the development and progression of prostate cancer. Although accumulating evidence suggests that general anesthetics, including opioids, affect cancer cell growth and impact patient prognosis, the effect of those drugs on androgen receptor in prostate cancer is not clear. The purpose of this study was to investigate the effect of the general anesthetic propofol on androgen receptor activity in prostate cancer cells. An androgen-dependent human prostate cancer cell line (LNCaP) was stimulated with dihydrotestosterone (DHT) and exposed to propofol. The induction of androgen receptor target genes was investigated using real-time reverse transcription polymerase chain reaction, and androgen receptor protein levels and localization patterns were analyzed using immunoblotting and immunofluorescence assays. The effect of propofol on the proliferation of LNCaP cells was analyzed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays. Propofol significantly inhibited DHT-induced expression of androgen receptor target genes in a dose- and time-dependent manner, and immunoblotting and immunofluorescence assays indicated that propofol suppressed nuclear levels of androgen receptor proteins. Exposure to propofol for 24h suppressed the proliferation of LNCaP cells, whereas 4h of exposure did not exert significant effects. Together, our results indicate that propofol suppresses nuclear androgen receptor protein levels, and inhibits androgen receptor transcriptional activity and proliferation in LNCaP cells.

Propofol inhibits lung cancer cell viability and induces cell apoptosis by upregulating microRNA-486 expression

Propofol is a frequently used intravenous anesthetic agent. Recent studies show that propofol exerts a number of non-anesthetic effects. The present study aimed to investigate the effects of propofol on lung cancer cell lines H1299 and H1792 and functional role of microRNA (miR)-486 in these effects. H1299 and/or H1792 cells were treated with or without propofol and transfected or not with miR-486 inhibitor, and then cell viability and apoptosis were analyzed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and flow cytometry. The expression of miR-486 was determined by quantitative real-time polymerase chain reaction (qRT-PCR) with or without propofol treatment. Western blot was performed to analyze the protein expression of Forkhead box, class O (FOXO) 1 and 3, Bcl-2 interacting mediator of cell death (Bim), and pro- and activated caspases-3. Results showed that propofol significantly increased the miR-486 levels in both H1299 and H1792 cells compared to untreated cells in a dose-dependent manner (P<0.05 or P<0.01). Propofol statistically decreased cell viability but increased the percentages of apoptotic cells and protein expressions of FOXO1, FOXO3, Bim, and pro- and activated caspases-3; however, miR-486 inhibitor reversed the effects of propofol on cell viability, apoptosis, and protein expression (P<0.05 or P<0.01). In conclusion, propofol might be an ideal anesthetic for lung cancer surgery by effectively inhibiting lung cancer cell viability and inducing cell apoptosis. Modulation of miR-486 might contribute to the anti-tumor activity of propofol.

Acquisition of heroin conditioned immunosuppression requires IL-1 signaling in the dorsal hippocampus

Opioid users experience increased incidence of infection, which may be partially attributable to both direct opiate-immune interactions and conditioned immune responses. Previous studies have investigated the neural circuitry governing opioid conditioned immune responses, but work remains to elucidate the mechanisms mediating this effect. Our laboratory has previously shown that hippocampal IL-1 signaling, specifically, is required for the expression of heroin conditioned immunosuppression following learning. The current studies were designed to further characterize the role of hippocampal IL-1 in this phenomenon by manipulating IL-1 during learning. Experiment 1 tested whether hippocampal IL-1 is also required for the acquisition of heroin conditioned immunosuppression, while Experiment 2 tested whether hippocampal IL-1 is required for the expression of unconditioned heroin immunosuppression. We found that blocking IL-1 signaling in the dorsal hippocampus with IL-1RA during each conditioning session, but not on interspersed non-conditioning days, significantly attenuated the acquisition of heroin conditioned immunosuppression. Strikingly, we found that the same IL-1RA treatment did not alter unconditioned immunosuppression to a single dose of heroin. Thus, IL-1 signaling is not a critical component of the response to heroin but rather may play a role in the formation of the association between heroin and the context. Collectively, these studies suggest that IL-1 signaling, in addition to being involved in the expression of a heroin conditioned immune response, is also involved in the acquisition of this effect. Importantly, this effect is likely not due to blocking the response to the unconditioned stimulus since IL-1RA did not affect heroin's immunosuppressive effects.

The Effects of Perioperative Regional Anesthesia and Analgesia on Cancer Recurrence and Survival After Oncology Surgery: A Systematic Review and Meta-Analysis

BACKGROUND AND OBJECTIVES

Potentially, perioperative regional anesthesia and analgesia (RA) could influence the outcomes of patients with cancer. The aim of this systematic review and meta-analysis was to evaluate the effects of perioperative RA on survival and cancer recurrence after oncologic surgery.

METHODS

The authors searched computerized databases (from inception to December 2014) and reference lists and considered all studies comparing the effects of RA on cancer recurrence or overall survival with that of general anesthesia (GA). Risk estimates were pooled to determine the effects of RA on risks of cancer recurrence and mortality. Twenty eligible studies were included.

RESULTS

Perioperative RA use was associated with improved overall survival (Hazard ratio [HR] = 0.84, 95% CI, 0.75 - 0.94; I =41%), but not with reduced cancer recurrence (HR=0.91, 95% CI, 0.70 - 1.18; I=83%).

CONCLUSIONS

Our meta-analysis suggests that RA may improve overall survival but not reduce cancer recurrence after oncologic surgery.

Spinal anesthesia does not impact prostate cancer recurrence in a cohort of men undergoing radical prostatectomy: an observational study

BACKGROUND AND OBJECTIVES

Prior studies suggest a possible association between the use of neuraxial-general anesthesia and a decrease in prostate cancer recurrence after radical prostatectomy. We examine the correlation of a spinal anesthesia-only technique on prostate cancer recurrence.

METHODS

Charts from consecutive radical prostatectomy patients of 3 experienced urologists from January 1999 to December 2005 were reviewed. In addition to the usual clinical and pathologic predictors of disease recurrence, patient records were queried for the type of anesthesia (general vs spinal) performed. A Cox proportional hazards model was used to determine the statistical significance of predictors of biochemical recurrence.

RESULTS

A total of 1964 patients-1166 and 798 receiving spinal with sedation or general anesthesia, respectively-had complete preoperative and follow-up data. In univariate proportional hazards analysis, the use of general anesthesia was associated with a trend toward an increased risk of biochemical recurrence when compared with the use of spinal anesthesia (hazard ratio, 1.29; 95% confidence interval, 0.99-1.66; P = 0.053). In multivariable analysis, the effect size (hazard ratio, 1.10; 95% confidence interval, 0.85-1.42; P = 0.458) was diminished by clinical and pathologic variables.

CONCLUSIONS

This was a retrospective study of patients with prostate cancer who have undergone radical prostatectomy during a time period when the practice of anesthesia for prostatectomy at our institution was transitioned from spinal to general anesthesia. In our study, when controlling for other predictors of advanced prostate cancer, the type of anesthetic given during prostatectomy had no effect on the risk of biochemical recurrence.

Sevoflurane promotes the expansion of glioma stem cells through activation of hypoxia-inducible factors in vitro

BACKGROUND

Growing evidences indicate that inhalational anaesthetics can enhance the growth and malignant potential of tumour cells and may affect tumour recurrence after surgery. Tumour stem cells play a vital role in tumour recurrence. This study investigates the effect of sevoflurane on glioma stem cells (GSCs) in vitro and the underlying molecular mechanisms in this process.

METHODS

Cultured GSCs were exposed to clinically relevant concentrations and durations of sevoflurane exposure. Cell proliferation and self-renewal capacity were determined. Expression of the stem cell marker CD133, vascular endothelial growth factor (VEGF), hypoxia-inducible factors (HIFs), and phosphorylated Akt, which is a protein kinase invoved in multiple cellular processes, were measured using western blotting. Small interfering RNAs and an Akt inhibitor were used to investigate specific pathways.

RESULTS

Compared with controls, cells exposed to 2% sevoflurane for 6 h induced a larger number of proliferated cells (31.2±7.6% vs 19.0±5.8%; P<0.01). Levels of CD133, VEGF, HIF-1α, HIF-2α, and p-Akt were up-regulated by sevoflurane in a time- and concentration-dependent manner. Small interfering RNA against HIFs decreased the percentage of proliferating GSCs after sevoflurane exposure and pre-treatment of cells with an Akt inhibitor abrogated the expression of HIFs induced by sevoflurane.

CONCLUSIONS

Sevoflurane can promote the expansion of human GSCs through HIFs in vitro. Inhaled anaesthetics may enhance tumour growth through tumour stem cells.

Ultrasound-guided Multilevel Paravertebral Blocks and Total Intravenous Anesthesia Improve the Quality of Recovery after Ambulatory Breast Tumor Resection

Background:

Regional anesthesia improves postoperative analgesia and enhances quality of recovery (QoR) after ambulatory surgery. This randomized, double-blinded, parallel-group, placebo-controlled trial examines the effects of multilevel ultrasound-guided paravertebral blocks (PVBs) and total intravenous anesthesia on QoR after ambulatory breast tumor resection.

Methods:

Sixty-six women were randomized to standardized general anesthesia (control group) or PVBs and propofol-based total intravenous anesthesia (PVB group). The PVB group received T1–T5 PVBs with 5 ml of 0.5% ropivacaine per level, whereas the control group received sham subcutaneous injections. Postoperative QoR was designated as the primary outcome. The 29-item ambulatory QoR tool was administered in the preadmission clinic, before discharge, and on postoperative days 2, 4, and 7. Secondary outcomes included block success, pain scores, intra- and postoperative morphine consumption, time to rescue analgesia, incidence of nausea and vomiting, and hospital discharge time.

Results:

Data from sixty-four patients were analyzed. The PVB group had higher QoR scores than control group upon discharge (146 vs. 131; P &lt; 0.0001) and on postoperative day 2 (145 vs. 135; P = 0.013); improvements beyond postoperative day 2 lacked statistical significance. None of the PVB group patients required conversion to inhalation gas–based general anesthesia or experienced block-related complications. PVB group patients had improved pain scores on postanesthesia care unit admission and discharge, hospital discharge, and postoperative day 2; their intraoperative morphine consumption, incidence of nausea and vomiting, and discharge time were also reduced.

Conclusion:

Combining multilevel PVBs with total intravenous anesthesia provides reliable anesthesia, improves postoperative analgesia, enhances QoR, and expedites discharge compared with inhalational gas- and opioid-based general anesthesia for ambulatory breast tumor resection.

Anesthetic techniques and cancer recurrence after surgery

Many of the most common anesthetics are used in surgical oncology, yet effects on cancer cells are still not known. Anesthesia technique could differentially affect cancer recurrence in oncologic patients undergoing surgery, due to immunosuppression, stimulation of angiogenesis, and dissemination of residual cancer cells. Data support the use of intravenous anesthetics, such as propofol anesthesia, thanks to antitumoral protective effects inhibiting cyclooxygenase 2 and prostaglandins E2 in cancer cells, and stimulation of immunity response; a restriction in the use of volatile anesthetics; restriction in the use of opioids as they suppress humoral and cellular immunity, and their chronic use favors angiogenesis and development of metastases; use of locoregional anesthesia compared with general anesthesia, as locoregional appears to reduce cancer recurrence after surgery. However, these findings must be interpreted cautiously as there is no evidence that simple changes in the practice of anesthesia can have a positive impact on postsurgical survival of cancer patients.

Perioperative evaluation of tumescent anaesthesia technique in bitches submitted to unilateral mastectomy

BACKGROUND

Tumescent anaesthesia (TA) is a widely used technique in oncologic surgeries necessitating large resection margins. This technique produces transoperative and postoperative analgesia, reduces surgical bleeding, and facilitates tissue divulsion. This prospective, randomised, blind study evaluated the use of TA in bitches submitted to mastectomy and compared the effect of TA with an intravenous fentanyl bolus. A 2.5-mcg/kg intravenous fentanyl bolus (n = 10) was compared with TA using 0.275% lidocaine (n = 10) in bitches submitted to unilateral mastectomy. Sedation was performed by intramuscular (IM) injection of 0.05 mg/kg of acepromazine combined with 2 mg/kg of meperidine. Anaesthesia was induced with 5 mg/kg of intravenous propofol and maintained with isoflurane/O2. Heart and respiratory rates; systolic, mean, and diastolic arterial blood pressures; central venous pressure; SpO2; ETCO2; inspired and expired isoflurane concentrations; and temperature were measured transoperatively. Visual analogue scales for sedation and pain and the Glasgow composite and Melbourne pain scales were used for postoperative assessment. The surgeon investigated the quality of the surgical approach, considering bleeding and resection ability, and the incidence of postoperative wound complications.

RESULTS

The heart rate was lower and the end-tidal isoflurane concentration was higher in dogs treated with fentanyl than in dogs treated with TA. A fentanyl bolus was administered to 8 of 10 dogs treated with fentanyl and to none treated with TA. Intraoperative bleeding and the mammary gland excision time were lower in dogs treated with TA. The maximal mean and individual plasma lidocaine concentrations were 1426 ± 502 ng/ml and 2443 ng/ml at 90 minutes after infiltration, respectively. The Glasgow Composite Pain Scale scores were higher in dogs treated with fentanyl than in dogs treated with TA until 2 hours after extubation.

CONCLUSIONS

Compared with intravenous fentanyl, TA in bitches: may be easily performed in non-inflamed, ulcerated, adhered mammary tumours; has an isoflurane-sparing effect; improves transoperative and immediate postoperative analgesia; is apparently safe for use in clinical conditions as evidenced by the fact that it did not produce any adverse signs or lidocaine plasma concentrations compatible with toxicity; does not modify the recovery time; and facilitates the surgical procedure without interfering with wound healing.

Major abdominal surgery for cancer: does epidural analgesia have a long-term effect on recurrence-free and overall survival?

BACKGROUND

Retrospective studies have suggested that regional analgesia combined with general anaesthesia could decrease cancer recurrence. The purpose of this study was to assess the influence of regional analgesia on recurrence-free (RFS) and overall survival in patients undergoing major intra-abdominal surgery for cancer.

METHOD

Patients previously included in a prospective randomized study comparing two postoperative techniques of analgesia were retrospectively studied. The EP group received general anaesthesia with bupivacaine thoracic epidural analgesia and the SC group received general anaesthesia with fentanyl followed by continuous subcutaneous morphine.

RESULTS

One hundred and thirty-two patients were analyzed (63 and 69 in SC and EP group, respectively) with a 17-year-median follow-up. After 5 years, RFS was 43% [95% CI: 32%-55%] in EP group and 24% [95% CI: 15%-36%] in SC group, but the difference did not reach statistical significance for RFS nor for overall survival (P=0.10 and 0.16 respectively). Using multivariable analysis over the whole follow-up period, the type of analgesia was not a statistically significant predictive factor for RFS (EP/SC, HR=1.3 [95% CI: 0.8-2.0%]). The anaesthesia effect changed moderately over the follow-up and HR for overall survival (EP/SC) reached statistical significance after 5, 6 and 8 years.

CONCLUSION

Despite a trend in favour of the epidural, this retrospective review of patients included in a previous randomized study failed to demonstrate a statistically significant association between the perioperative analgesia and RFS after abdominal surgery for cancer. The duration of follow-up may have an impact on the analgesia effect on survival.

WITHDRAWN: Propofol reduces MMPs expression by inhibiting PI3K/AKT activity in human HepG2 cells

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Propofol induces proliferation and invasion of gallbladder cancer cells through activation of Nrf2

BACKGROUND

Propofol is one of the most commonly used intravenous anaesthetic agents during cancer resection surgery, but the effect of propofol on gallbladder cancer is not clear. NF-E2-related factor 2 (Nrf2) is abundantly expressed in cancer cells and relates to proliferation, invasion, and chemoresistance. The aims of the current study were to evaluate effects of propofol on the behavior of human GC cells and role of Nrf2 in these effects.

METHOD

The effects of propofol on cell proliferation, apoptosis, and invasion were detected by MTT assays, flow cytometry, and transwell assay. Also, activation of Nrf2 was determined by western blot, RT-PCR, and immunofluorescence assays. Nrf2 was knocked-down in GBC-SD cells by shRNA before evaluating the role of Nrf2 in the influence of propofol on biological behaviors.

RESULTS

Propofol promoted the proliferation of GBC-SD cells in a dose- and time- dependent manner. After exposure to propofol for 48 h, GBC-SD cells showed decreased apoptosis and increased invasion. Also, propofol over-expressed Nrf2 at both the protein and mRNA levels and induced translocation of Nrf2 into the nucleus. Finally, loss of Nrf2 by shRNA reversed the effect of propofol on cell proliferation, apoptosis, and invasion.

CONCLUSION

Propofol induces proliferation and promotes invasion of GC cells through activation of Nrf2.

George M, Freedman H, Barakat KH, Damaraju S, Hameroff S, Tuszynski JA. Computational predictions of volatile anesthetic interactions with the microtubule cytoskeleton: implications for side effects of general anesthesia

The cytoskeleton is essential to cell morphology, cargo trafficking, and cell division. As the neuronal cytoskeleton is extremely complex, it is no wonder that a startling number of neurodegenerative disorders (including but not limited to Alzheimer's disease, Parkinson's disease and Huntington's disease) share the common feature of a dysfunctional neuronal cytoskeleton. Recently, concern has been raised about a possible link between anesthesia, post-operative cognitive dysfunction, and the exacerbation of neurodegenerative disorders. Experimental investigations suggest that anesthetics bind to and affect cytoskeletal microtubules, and that anesthesia-related cognitive dysfunction involves microtubule instability, hyper-phosphorylation of the microtubule-associated protein tau, and tau separation from microtubules. However, exact mechanisms are yet to be identified. In this paper the interaction of anesthetics with the microtubule subunit protein tubulin is investigated using computer-modeling methods. Homology modeling, molecular dynamics simulations and surface geometry techniques were used to determine putative binding sites for volatile anesthetics on tubulin. This was followed by free energy based docking calculations for halothane (2-bromo-2-chloro-1,1,1-trifluoroethane) on the tubulin body, and C-terminal regions for specific tubulin isotypes. Locations of the putative binding sites, halothane binding energies and the relation to cytoskeleton function are reported in this paper.

Genotoxic effects of anesthetic agents: an update

INTRODUCTION

Exposure to anesthetics in the health environment may entail a health risk for patients and operating room personnel. Knowing the effects of anesthetic agents on genetic material could be a valuable basic support for anesthesia care providers to improve treatment performance, increase patient safety and reduce the risks for patients and staff in the operating room.

AREAS COVERED

Relevant literature was identified using MEDLINE, CINAHL® and Cochrane Library databases. Over 200 abstracts for articles published from 1980 to 2010 were examined. Original articles were reviewed and relevant citations from these articles were also considered.

EXPERT OPINION

Despite some conflicting results, the current available data indicate that exposure to anesthetics, especially nitrous oxide and halogenated agents, is associated with general and genotoxic risks, whereas intravenous agents, such as propofol and its metabolites are not associated with genotoxic effects. Moreover, given that different anesthetic drugs are used in combination it is, thus, very difficult to understand whether the observed effects or absence of effects are due to an individual agent action or linked to a synergy action of different anesthetics involved. Further clinical and experimental evidence is warranted.