Intravenous Patient-Controlled Analgesia Versus Oral Opioid to Maintain Analgesia for Severe Cancer Pain: A Randomized Phase II Trial.

BACKGROUND: Optimal analgesic maintenance for severe cancer pain is unknown. This study evaluated the efficacy and safety of intravenous patient-controlled analgesia (IPCA) with continuous infusion plus rescue dose or bolus-only dose versus conventional oral extended-release morphine as a background dose with normal-release morphine as a rescue dose to maintain analgesia in patients with severe cancer pain after successful opioid titration. METHODS: Patients with persistent severe cancer pain (≥7 at rest on the 11-point numeric rating scale [NRS]) were randomly assigned to 1 of 3 treatment arms: (A1) IPCA hydromorphone with bolus-only dose where dosage was 10% to 20% of the total equianalgesic over the previous 24 hours (TEOP24H) administered as needed, (A2) IPCA hydromorphone with continuous infusion where dose per hour was the TEOP24H divided by 24 and bolus dosage for breakthrough pain was 10% to 20% of the TEOP24H, and (B) oral extended-release morphine based on TEOP24H/2 × 75% (because of incomplete cross-tolerance) every 12 hours plus normal-release morphine based on TEOP24H × 10% to 20% for breakthrough pain. After randomization, patients underwent IPCA hydromorphone titration for 24 hours to achieve pain control before beginning their assigned treatment. The primary endpoint was NRS over days 1 to 3. RESULTS: A total of 95 patients from 9 oncology study sites underwent randomization: 30 into arm A1, 32 into arm A2, and 33 into arm B. Arm B produced a significantly higher NRS over days 1 to 3 compared with arm A1 or A2 (P<.001). Daily NRS from day 1 to day 6 and patient satisfaction scores on day 3 and day 6 were worse in arm B. Median equivalent-morphine consumption increase was significantly lower in A1 (P=.024) among the 3 arms. No severe adverse event occurred in any arm. CONCLUSIONS: Compared with oral morphine maintenance, IPCA hydromorphone for analgesia maintenance improves control of severe cancer pain after successful titration. Furthermore, IPCA hydromorphone without continuous infusion may consume less opioid.

Gabapentin enhances the antinociceptive effect of intrathecal morphine in refractory cancer pain patients.

PURPOSE: Morphine infusion through Intrathecal Drug Delivery System (IDDS) is widely used to relieve refractory cancer pain. However, continuous escalation of morphine dose caused by opioid tolerance and/or progress of cancer was commonly observed. Combining morphine with medications of different analgesic mechanisms is applied to blunt the rate of morphine increase. The purpose of this study was to determine the analgesic efficacy and safety of combining gabapentin with morphine after IDDS implantation. METHODS: This study compared patients that received IDDS implantation from January 1, 2017 to November 10, 2018 in our institute. Key outcomes included change in mean pain score, dose of morphine used in patients, percentage of patients with 30% and 50% reduction in mean pain score, Patient Global Impression of Change scores, breakthrough pain characters and side effects. RESULTS: 34 patients in the combination group (morphine + gabapentin) and 40 patients in the monotherapy group(morphine)were analyzed. The results showed that both therapy groups achieved similar analgesic efficacy, demonstrated by Numerical rating scale (2.42 ± 0.88 vs 2.57 ± 0.85; Combination vs Monotherapy), PGIC and responder status. Mean daily dose of morphine was significantly lower in combination group compared to monotherapy group (3.54 ± 1.29 mg vs 4.64 ± 1.28 mg, P = 0.007). More patients experienced dizziness and somnolence after receiving combination therapy compared to morphine-alone treatment although no statistical significance was found (P = 0.49). CONCLUSION: Addition of gabapentin achieved similar analgesic efficacy with lower dose of morphine compared to morphine alone accompanying with higher incidence of dizziness and somnolence.

MiR-21 Participates in the PD-1/PD-L1 Pathway-Mediated Imbalance of Th17/Treg Cells in Patients After Gastric Cancer Resection.

BACKGROUND: The programmed cell death-1/programmed cell death-ligand 1 (PD-1/PD-L1) pathway has been shown to be involved in trauma-induced immunosuppression and to influence CD4+ T cell differentiation. MicroRNA (miR)-21 is a critical player in immune responses. However, it remains largely unknown whether miR-21 is regulated by PD-1 and influences CD4+ T-cell lineage choice after gastric cancer resection. METHODS: In the present study, we analyzed the percentages of T-helper (Th)-17/regulatory T (Treg) cells and PD-1/PD-L1 expression on peripheral blood mononuclear cells (PBMCs) during the perioperative period. We also detected the secretion of interleukin (IL)-17 and transforming growth factor (TGF)-ß1 using enzyme-linked immunosorbent assays (ELISAs). Furthermore, PBMCs isolated from patients were transfected with or without adenovirus-short hairpin-PD-1 (Ad-sh-PD1), pre-miR-21 or adenovirus-green fluorescent protein (Ad-GFP), and the percentages of Th17/Treg cells and related transcription factors were measured. RESULTS: In patients who underwent gastric cancer resection, the number of Th17 cells decreased, whereas the number of Treg cells increased, accompanied by an increased expression of PD-1/PD-L1. In addition, the expression of RORγt and IL-17 decreased, whereas the expression of Foxp3 and TGF-ß1 increased. In vitro, silencing PD-1 via Ad-sh-PD1 promoted the expression of miR-21 and increased the percentage of Th17 cells, but decreased the percentage of Treg cells. The overexpression of miR-21 increased the percentage of Th17 cells but decreased the percentage of Treg cells. CONCLUSIONS: Our study demonstrated that gastric cancer resection altered the balance of Th17/Treg cells and increased PD-1/PD-L1 expression. In the in vitro experiments, the transfection of Ad-sh-PD1 ameliorated Th17/Treg cell imbalance partially by increasing the expression of miR-21.

miR-577 inhibits glioblastoma tumor growth via the Wnt signaling pathway.

microRNAs (miRNAs) are commonly altered in glioblastoma. Publicly available algorithms suggest the Wnt pathway is a potential target of miR-577 and the Wnt pathway is commonly altered in glioblastoma. Glioblastoma has not been previously evaluated for miR-577 expression. Glioblastoma tumors and cell lines were evaluated for their expression of miR-577. Cell lines were transfected with miR-577, miR-577-mutant, or control mimics to evaluate the effect of miR-577 expression on cell proliferation in vitro and in an animal model. Wnt pathway markers were also evaluated for their association with miR-577 expression. miR-577 expression was decreased in 33 of 40 (82.5%) glioblastoma tumors and 5 of 6 glioblastoma cell lines. miR-577 expression correlated negatively with cell growth and cell viability. miR-577 down-regulation was associated with increased expression of the Wnt signaling pathway genes lipoprotein receptor-related protein (LRP) 6 (LRP6) and ß-catenin. Western blot analysis confirmed decreased expression of the Wnt signaling pathway genes Axin2, c-myc, and cyclin D1 in miR-577 transfected cells. miR-577 expression is down-regulated in glioblastoma. miR-577 directly targets Wnt signaling pathway components LRP6 and ß-catenin. miR-577 suppresses glioblastoma multiforme (GBM) growth by regulating the Wnt signaling pathway.

Inhibition of autophagy induced by quercetin at a late stage enhances cytotoxic effects on glioma cells.

Glioma is the most common primary brain tumor in the central nervous system (CNS) with high morbidity and mortality in adults. Although standardized comprehensive therapy has been adapted, the prognosis of glioma patients is still frustrating and thus novel therapeutic strategies are urgently in need. Quercetin (Quer), an important flavonoid compound found in many herbs, is shown to be effective in some tumor models including glioma. Recently, it is reported that adequate regulation of autophagy can strengthen cytotoxic effect of anticancer drugs. However, it is not yet fully clear how we should modulate autophagy to achieve a satisfactory therapeutic effect. 3-Methyladenine (3-MA) and Beclin1 short hairpin RNA (shRNA) were used to inhibit the early stage of autophage while chloroquine (CQ) to inhibit the late stage. MTT assay was implemented to determine cell viability. Transmission electron microscopy, western blot, and immunohistochemistry were adopted to evaluate autophagy. Western blot, flow cytometry, and immunohistochemistry were used to detect apoptosis. C6 glioma xenograft models were established to assess the therapeutic effect (the body weight change, the median survival time, and tumor volume) in vivo. Quercetin can inhibit cell viability and induce autophagy of U87 and U251 glioma cells in a dose-dependent manner. Inhibition of early-stage autophagy by 3-MA or shRNA against Beclin1 attenuated the quercetin-induced cytotoxicity. In contrast, suppression of autophagy at a late stage by CQ enhanced the anti-glioma efficiency of quercetin. Therapeutic effect of quercetin for malignant glioma can be strengthened by inhibition of autophagy at a late stage, not initial stage, which may provide a novel opportunity for glioma therapy.

XBP1 silencing decreases glioma cell viability and glycolysis possibly by inhibiting HK2 expression.

Glioma cells rely on glycolysis to obtain energy and sustain their survival under microenvironmental stress in vivo. The mechanisms of regulation of glycolysis in glioma cells are unclear. Signaling pathway mediated by the transcription factor X box-binding protein 1 (XBP1) is one of the most important pathways of unfolded protein response which is comprehensively activated in cancer cells upon the microenvironmental stress. Here we showed that XBP1 was significantly activated in glioma tissues in vivo. XBP1 silencing resulted in decreasing of glioma cell viability and ATP/lactate production under hypoxia, which is possibly mediated by inhibition of Hexokinase II (HK2)'s expression. More importantly, XBP1 silenced glioma cells showed the decrease of tumor formation capacity. Our results revealed that XBP1s activation was involved in glioma glycolysis regulation and might be a potential molecular target for glioma treatment.

Impact of autophagy inhibition at different stages on cytotoxic effect of autophagy inducer in glioblastoma cells.

BACKGROUND/AIMS: Glioblastoma multiforme (GBM) is the most malignant primary brain tumor with a poor prognosis. Combination treatment of autophagy inducer and autophagy inhibitor may be a feasible solution to improve the therapeutic effects. However, the correlation between them is unclear. The purpose of this study was to investigate the effect of autophagy inhibition at different stages on cytotoxicity of autophagy inducers in glioblastoma cells. METHODS: Autophagy inhibition at early stage was achieved by 3-methyladenine (3-MA) or Beclin 1 shRNA. Autophagy inhibition at late stage was achieved by chloroquine (CQ) or Rab7 shRNA. Cell viability was assessed by MTT assay. Autophagy was measured using transmission electron microscopy and western blot. Apoptosis was measured using western blot and flow-cytometry. RESULTS: Inhibition of early steps of autophagy by 3-MA or Beclin 1 knockdown decreased the toxic effect of arsenic trioxide (ATO) in GBM cell lines. In contrast, blockade of autophagy flux at late stage by CQ or Rab7 knockdown enhanced the cytotoxicity of ATO, and caused accumulation of degradative autophagic vacuoles and robust apoptosis. Moreover, depletion of Beclin 1 abolished the synergistic effect of ATO and CQ by reducing autophagy and apoptosis. Combination of CQ with other autophagy inducers also induced synergistic apoptotic cell death. CONCLUSION: These results suggest that inhibition of late process of autophagy, not initial step, increases the cytotoxic effect of autophagy inducers via autophagy and apoptosis, which may contribute to GBM chemotherapy.

Abbreviated levetiracetam treatment effects on behavioural and histological outcomes after experimental TBI.

OBJECTIVE: Long-term prophylactic treatment with levetiracetam (LEV) has multiple neuroprotective effects in a traumatic brain injury (TBI) rat model. Although a rational time-frame of seizure prophylactic treatment with LEV for after TBI is not well established, clinical prophylaxis with LEV often includes treatment duration similar to clinical treatment guidelines with Phenytoin. Thus, this study investigated the effects of abbreviated LEV treatment on behavioural function and histological evidence of neuroprotection. RESEARCH DESIGN: Pre-clinical trial of abbreviated LEV dosing in an experimental model of TBI Methods: After either controlled cortical impact (CCI) injury or sham surgery, rats received three 50 mg kg(-1) doses over 24 hours or vehicle. After injury/sham surgery, beam performance, spatial learning, contusion volume size and hippocampal neuron survival were assessed. RESULTS: Abbreviated LEV did not improve motor or cognitive performance after TBI. Further, abbreviated LEV did not improve hippocampal neuron sparing or contusion volumes compared with vehicle controls. CONCLUSIONS: Together with previous work assessing daily LEV treatment, these results suggest that longer-term therapy may be required to confer beneficial effects within these domains. These findings may guide (1) future experimental studies assessing minimal effective dosing for neuroprotection and anti-epileptogenesis and (2) treatment guideline updates for seizure prophylaxis post-TBI.

Negative Impact of Intra-Operative Blood Transfusion on Survival Outcomes of Hepatocellular Carcinoma Patients.

Background: Studies have reported that blood transfusion may have an association with survival outcomes of cancer patients. This study was aimed at finding the effect of intra-operative blood transfusion on the prognosis of patients of hepatocellular carcinoma (HCC). Methods: This was a retrospective study. HCC patients who underwent tumor resection from January 2013 to November 2018 at Harbin Medical University Cancer Hospital were included. The survival time of patients receiving or not receiving blood transfusion during the operation were compared. Results: Of HCC patients, 21.1% (102/484) received intra-operative blood transfusion. After propensity score matching, 87 pairs of patients were included in the study. In the subset of patients with a tumor size of >4 cm, univariable analysis found that there were significant differences in recurrence-free survival (RFS; P=0.004) and overall survival (OS; P=0.028) between blood transfusion and non-blood transfusion groups. After multivariable Cox regression analysis, intra-operative blood transfusion was an independent risk factor for RFS (HR: 2.011, 95% CI: 1.146-3.529, P=0.015), but not for OS (HR: 1.862, 95% CI: 0.933-3.715, P=0.078) in the subset of patients with a tumor size of >4 cm. Conclusion: Intra-operative blood transfusion was associated with worse RFS in HCC patients with a tumor size of >4 cm.

Effect of Intraoperative Opioid Dose on Perioperative Neutrophil-to-Lymphocyte Ratio and Lymphocyte-to-Monocyte Ratio in Glioma.

Background: The neutrophil-to-lymphocyte ratio (NLR) and lymphocyte-to-monocyte ratio (LMR) are inflammatory biomarkers. Until now, it is unknown the impact of opioid dosage on perioperative immunity in glioma patients. The aim of this study was to explore the effect of intraoperative opioid dosage on perioperative immune perturbations using NLR and LMR as inflammatory biomarkers and evaluate the correlation between inflammatory biomarkers and pathological grade of glioma. Methods: The study included 208 patients with primary glioma who underwent glioma resection from February 2012 to November 2019 at Harbin Medical University Cancer Hospital. Complete blood count (CBC) was collected at 3 time points: one week before surgery, and 24 hours and one week after surgery. Patients were divided into high-dose and low-dose groups, based on the median value of intraoperative opioid dose. The relationships between perioperative NLR, LMR and intraoperative opioid dosage were analyzed using repeated measurement analysis of variance (ANOVA). Correlations between preoperative various factors and pathological grade were analyzed by Spearman analysis. Receiver operating characteristic (ROC) curves were performed to assess the predictive performance of the NLR and LMR for pathological grade. Results: The NLR (P=0.020) and lower LMR (P=0.037) were statistically significant different between high-dose and low-dose groups one week after surgery. The area under the curve (AUC) of the NLR to identify poor diagnosis was 0.685, which was superior to the LMR (AUC: 0.607) and indicated a correlation between the NLR with pathological grade. The preoperative NLR (P=0.000), LMR (P=0.009), age (P=0.000) and tumor size (P=0.001) exhibited a significant correlation with the pathological grade of glioma. Conclusion: Intraoperative opioids in the high-dose group were associated with higher NLR and lower LMR in postoperative glioma patients. The preoperative NLR and LMR demonstrated predictive value for distinguishing between high-grade and low-grade gliomas.

Non-spatial pre-training in the water maze as a clinically relevant model for evaluating learning and memory in experimental TBI.

Explicit and implicit learning and memory networks exist where each network can facilitate or inhibit cognition. Clinical evidence suggests that implicit networks are relatively preserved after traumatic brain injury (TBI). Non-spatial pre-training (NSPT) in the Morris Water Maze (MWM) provides the necessary behavioral components to complete the task, while limiting the formation of spatial maps. Our study utilized NSPT in the MWM to assess implicit and explicit learning and memory system deficits in the controlled cortical impact (CCI) model of TBI. 76 adult male Sprague-Dawley rats were divided: CCI vs. sham surgery, NSPT vs. No-NSPT, and cued vs. non-cued groups. NSPT occurred for 4d prior to surgery (dynamic hidden platform location, extra-maze cues covered, static pool entry point). Acquisition (d14-18), Probe/Visible Platform (d19), and Reversal (d20-21) trials were conducted with or without extra-maze cues. Novel time allocation and search strategy selection metrics were utilized. Results indicated implicit and explicit learning/memory networks are distinguishable in the MWM. In the cued condition, NSPT reduced thigmotaxis, improved place learning, and largely eliminated the apparent injury-induced deficits typically observed between untrained CCI and sham rats. However, among NSPT groups, incorporation of cues into search strategy selection for CCI rats was relatively impaired compared to shams. Non-cued condition performance showed sham/NSPT and CCI/NSPT rats perform similarly, suggesting implicit memory networks are largely intact 2weeks after CCI. Place learning differences between CCI/NSPT and sham/NSPT rats more accurately reflect spatial deficits in our CCI model compared to untrained controls. These data suggest NSPT as a clinically relevant construct for evaluating potential neurorestorative and neuroprotective therapies. These findings also support development of non-spatial cognitive training paradigms for evaluating rehabilitation relevant combination therapies.

Clinical Significance of Mean Platelet Volume Combined with Neutrophil-Lymphocyte Ratio in Predicting the Therapeutic Effect of Splanchnic Neurolysis.

Introduction: In most cases of pain related to abdominal tumors, increasing the dosage of analgesics still makes the pain difficult to alleviate. Splanchnic neurolysis is a new treatment option. However, not all patients receiving splanchnic neurolysis treatment will achieve satisfactory results. The aim of this study is to retrospectively analyze the predictive value of preoperative serum immune indicators (white blood cells, neutrophils, lymphocytes, and platelets) for the efficacy of splanchnic neurolysis. Methods: The abdominal cancer patients (pancreatic cancer, liver cancer, gastric cancer, colorectal cancer, cholangiocarcinoma, and renal cancer) admitted to the Department of Pain Medicine, Harbin Medical University Cancer Hospital from January 2017 to October 2020 were collected. We evaluate the efficacy of splanchnic neurolysis by assessing the dosage of opioids and Numerical Rating Scale (NRS) scores of patients 24 to 48 hr before and after splanchnic neurolysis. The predictive value of preoperative serum immune indicators on the efficacy of splanchnic neurolysis was analyzed using Receiver Operating Characteristic (ROC). Contract the Nomogram prediction model by R software. Results: We found that Mean Platelet Volume (MPV) has statistical significance for predicting splanchnic neurolysis efficacy in digestive system tumors. MPV and Neutrophil-Lymphocyte Ratio (NLR) are independent predictors and have statistical significance in predicting splanchnic neurolysis efficacy in pancreatic cancer. The combination of MPV and NLR had satisfactory predictive value in pancreatic cancer (AUC = 0.715) and the nomogram model was constructed. Furthermore, there was a negative correlation between lymphocyte count and NRS score, and a positive correlation between Platelet-Lymphocyte Ratio (PLR) and NRS score. Discussion: The combined detection of MPV and NLR has important clinical predictive value for the postoperative efficacy of splanchnic neurolysis in pancreatic cancer.

Dose of intra-operative opioids has no impact on recurrence or survival in primary liver cancer.

BACKGROUND: Intra-operative use of opioid analgesics might have an impact on cancer recurrence and survival after surgery. The objective of this study was to investigate the association between the intra-operative fentanyl equivalents and survival outcomes in patients with primary liver cancer after receiving hepatectomy. METHODS: This was a retrospective single-center cohort study, and clinical data of 700 patients with primary liver cancer who underwent hepatectomy in Harbin Medical University Cancer Hospital from September 2013 to August 2018 were reviewed. After propensity matching, 376 patients were included. Patients were divided into high-dose and low-dose groups according to the median intra-operative fentanyl equivalents (1.500 mg). Kaplan Meier curve and Cox proportional hazards regression model were used. RESULTS: Results of univariable analysis showed there were no significant differences in recurrence-free survival (RFS) (p = 0.136) and overall survival (OS) (p = 0.444) between high-dose fentanyl equivalents and low-dose fentanyl equivalents group. The multivariable Cox regression analysis found that the dose of intra-operative fentanyl equivalents was not associated with RFS (HR: 1.119, 95%CI: 0.851-1.472, p = 0.422) or OS (HR: 0.939, 95%CI: 0.668-1.319, p = 0.715). CONCLUSIONS: The amounts of intra-operative fentanyl equivalents had no impact on recurrence-free or overall survival in patients with primary liver cancer after curative hepatectomy.

The combined analgesic effect of pregabalin and morphine in the treatment of pancreatic cancer pain, a retrospective study.

BACKGROUND: Pregabalin is commonly used to relieve neuropathic pain. However, data are lacking on its efficacy for the treatment of chronic cancer pain. The purpose of this study was to determine the analgesic efficacy of pregabalin combined with morphine in the management of pancreatic cancer pain. METHODS: This study reviewed patients who were prescribed morphine and 150 mg/d pregabalin between 1 January 2017 and 10 November 2018 in our institute. The primary outcomes of this study were the average pain score and dose of morphine. Secondary outcomes included characters of breakthrough cancer pain, functional interference related to pain, anxiety/depression status, and incidence of treatment-related adverse events during the study. RESULTS: A total of 240 patients with pain related to pancreatic cancer were included in the study. The results showed that patients of both combination therapy group (pregabalin+morphine) and monotherapy group (morphine) achieved similar analgesic efficacy, demonstrated by NRS (2.4 ± 0.9 vs. 2.6 ± 0.9; combination vs. monotherapy) at the end of the study. Mean daily dose of morphine used in the combination group was significant lower compared to monotherapy group (39.5 ± 16.0 mg vs. 61.5 ± 19.3 mg, net difference 23.5, 95% CI: 18.4-28.6, p < â€Š0.001). The change of functional interference score related to pain was significantly different between combination and monotherapy group (12.0 ± 0.4 vs. 9.8 ± 4.9; net difference, 2.3; 95% CI: 1.1-3.3; p < 0.001). Patients in combination therapy group had experienced shorter duration of breakthrough cancer pain than those in monotherapy group (X2 p < 0.001, Cramer's V:0.36). The incidence of somnolence, dizziness, and cognitive dysfunction were significantly higher in the combination group compared to monotherapy group. No serious treatment-related side effects were observed. CONCLUSIONS: The findings of this study supported the use of pregabalin with morphine to relieve pain in patients of pancreatic cancer.

Bone pain from spinal metastases: Iodine-125 brachytherapy.

OBJECTIVES: This study evaluated the analgesic efficacy and safety of CT-guided iodine-125 (125I) brachytherapy in patients with spinal metastasis-induced pain who were not suitable to receive radiotherapy. METHODS: A cohort of 68 patients with spinal metastasis induced pain not fully relieved by opioids and did not receive external beam radiation therapy due to poor general status were enrolled and underwent CT-guided 125I brachytherapy for analgesic treatment. RESULTS: Patients were followed for 8 weeks after brachytherapy. Mean Numerical Rating Scale score before brachytherapy was 7.3±1.3 and decreased to 3.3±0.9, 2.6±0.8, 2.7±0.8, 2.9±0.9 and 3.3±1.1 at weeks 1, 2, 4, 6 and 8, respectively, after brachytherapy. Daily dose of morphine equivalent was 105.1±28.0 mg before brachytherapy and decreased to 45.3±13.7, 39.9±14.2, 40.4±14.9, 48.5±18.0 and 62.4±17.5 mg at weeks 1, 2, 4, 6 and 8, respectively, after brachytherapy. Patients had fewer daily episodes of breakthrough pain after brachytherapy (p<0.001). Patients had improvement in pain-related functional interference and in hospital anxiety and depression score after brachytherapy. CONCLUSIONS: CT-guided 125I brachytherapy is an effective and safe intervention for patients with spinal metastasis-induced pain who are not able to receive radiation therapy.

Programmed death 1/programmed cell death-ligand 1 pathway participates in gastric surgery-induced imbalance of T-helper 17/regulatory T cells in mice.

BACKGROUND: The T-helper 17 (Th17)/regulatory T (Treg) cell balance is essential for immune homeostasis. However, the effects of gastric surgery on this balance remain unclear. The aim of present study is to identify the influence of gastric surgery on Th17/Treg cell balance and the role of programmed death 1 (PD-1)/programmed cell death-ligand 1 (PD-L1) pathway in this process. METHODS: Mice were divided into control, sham, and surgery group randomly. Animals in surgery group accepted partial gastrectomy. Mice in sham group only received laparotomy without partial gastrectomy. Then, we detected the percentages of Treg and Th17 cells, the expression of fork-head/winged helix transcription factor (Foxp3) and retinoic acid-related orphan receptor γt (RORγt) in splenocytes, as well as plasma levels of transforming growth factor (TGF)-ß1 and interleukin (IL)-17 on Days 1, 3, 5, 7 after surgery. We also analyzed the expression of PD-1 and PD-L1. The roles of PD-1/PD-L1 on the Th17/Treg balance were evaluated by the induction of Th17 or Treg cells in the presence or absence of PD-1 antibody and recombinant PD-L1 immunoglobulin (Ig) in vitro. RESULTS: The percentage of Treg cells increased, accompanied with elevated expression of Foxp3 and TGF-ß1 (p < 0.05), whereas the percentage of Th17 cells and the expression of RORγt and IL-17 decreased in mice that underwent partial gastrectomy (p < 0.05). The levels of PD-1 and PD-L1 were higher in surgery group than those in control and sham groups (p < 0.05). In vitro, the polarization of Th17 cells was enhanced, and the polarization of Treg cells was inhibited in anti-PD-1 treatment group compared with that in isotype group (p < 0.05). CONCLUSION: Partial gastrectomy resulted in Th17/Treg imbalance, and increased the expression of PD-1 and PD-L1. blockade of PD-1/PD-L1 pathway alleviated gastric surgery-induced imbalance of Th17/Treg cells.

Effects of Cannabinoid Type 2 Receptor Agonist AM1241 on Morphine-Induced Antinociception, Acute and Chronic Tolerance, and Dependence in Mice.

Morphine is a potent opioid analgesic used to alleviate moderate or severe pain, but the development of drug tolerance and dependence limits its use in pain management. Previous studies showed that cannabinoid type 2 (CB2) receptor ligands may modulate opioid effects. However, there is no report of the effect of CB2 receptor agonist on acute morphine tolerance and physical dependence. We therefore investigated the effect of a CB2 receptor agonist (AM1241) on morphine-induced morphine tolerance and physical dependence in mice. Repeated coadministration of AM1241 (1 or 3mg/kg intraperitoneally) and morphine (10mg/kg subcutaneously) for 7days increased the mechanical paw withdrawal threshold in mice as measured by the von Frey filament test, and 3mg/kg AM1241 in combination with morphine increased the thermal paw withdrawal latency as measured by the hot-plate test. Combination with 3mg/kg AM1241 and morphine increased acute morphine antinociception. Coadministration of 1 or 3mg/kg AM1241 and morphine reduced acute morphine tolerance, and 3mg/kg AM1241 reduced chronic morphine tolerance. Coadministration of 1 or 3mg/kg AM1241 and morphine reduced naloxone-precipitated withdrawal jumping, but not diarrhea. Coadministration of AM1241 and morphine did not inhibit spontaneous locomotor activity. Pretreatment with 3mg/kg AM1241 decreased the chronic morphine-induced Iba1 expression in spinal cord. Coadministration of AM1241 (3 mg/kg) reduced the production of interleukin-1ß, tumor necrosis factor-α, and interleukin-6 induced by long-term and acute morphine treatment. Our findings suggest that the coadministration of the CB2 receptor agonist and morphine could increase morphine antinociception and reduce morphine tolerance and physical dependence in mice. PERSPECTIVE: The combination of a CB2 agonist and morphine may provide a new strategy for better treatment of acute and chronic pain and prevention of opioid tolerance and dependence. This finding may also provide a clue for the treatment of opioid tolerance and dependence in clinics.

Enhanced radiation-induced cytotoxic effect by 2-ME in glioma cells is mediated by induction of cell cycle arrest and DNA damage via activation of ATM pathways.

Glioblastoma multiform is the most common malignant primary brain tumor in adults, but there remains no effective therapeutic approach. 2-methoxyestradiol (2-ME), which is a naturally occurring metabolite of 17beta-estradiol, was shown to enhance radiotherapeutic effect in certain tumors; however, whether 2-ME can also enhance the sensitivity of glioma cells to radiotherapy remains unknown. The present study, therefore, was to address this issue using two human glioma cell lines (T98G and U251MG). These cells were irradiated with and without 2-ME and then clonogenic assay, apoptosis assay, DNA damage, and cell cycle change were examined. Results showed that 2-ME significantly enhances radiation-induced cell death in both glioma cells, shown by decreasing cell viability and increasing apoptotic cell death. No such radiosensitizing effect was observed if cells pre-treated with Estrodiol, suggesting the specifically radiosensitizing effect of 2-ME rather than a general effect of estrodials. The enhanced radio-cytotoxic effect in glioma cells by 2-ME was found to be associated with its enhancement of G(2)/M arrest and DNA damage, and phosphorylated ATM protein kinases as well as cell cycle checkpoint protein Chk2. Furthermore, inhibition of ATM by ATM inhibitor abolished 2-ME-activated Chk2 and enhanced radio-cytotoxic effects. These results suggest that 2-ME enhancement of the sensitivity of glioma cell lines to radiotherapy is mediated by induction of G2/M cell cycle arrest and increased DNA damage via activation of ATM kinases.

2-methoxyestradiol, an endogenous mammalian metabolite, radiosensitizes colon carcinoma cells through c-Jun NH2-terminal kinase activation.

PURPOSE: 2-Methoxyestradiol (2ME), an estrogen metabolite, induces apoptosis in various cell types. We investigated whether 2ME pretreatment can radiosensitize colon adenocarcinoma cells. EXPERIMENTAL DESIGN: Radiosensitizing effects of 2ME were evaluated by cell death, clonogenic assay, nuclear fragmentation, and tumor progression of xenografts. Ionizing radiation-induced DNA damage was evaluated by histone H2AX phosphorylation and its foci. The c-Jun NH2-terminal kinase (JNK) activation was evaluated by anti-phosphorylated JNK antibody and inhibited by the JNK-specific inhibitor SP600125 or dominant-negative SEK1 expression. RESULTS: Clonogenic assays revealed that 2ME, but not estradiol, radiosensitized three colon carcinoma cells, DLD-1, HCT-8, and HCT-15, and strongly suppressed tumor progression of DLD-1 xenografts. Gene transfer-mediated Bcl-xL overexpression largely abolished both augmented apoptosis and reduced survival fractions. Pretreatment with 2ME enhanced H2AX phosphorylation, its foci, and phosphorylation of ATM kinase and delayed re-entry of cell cycle progression after ionizing radiation. Augmentation of both radiosensitivity and H2AX phosphorylation was substantially reduced by SP600125 or overexpression of a dominant-negative mutant SEK1. CONCLUSION: 2ME radiosensitized colon carcinoma cells through enhanced DNA damage via JNK activation, thereby representing a novel radiosensitizing therapy against colon cancer.

Effects of coadministration of low dose cannabinoid type 2 receptor agonist and morphine on vanilloid receptor 1 expression in a rat model of cancer pain.

Morphine is widely used as an analgesic to treat moderate to severe pain, but chronic morphine use is associated with development of tolerance and dependence, which limits its analgesic efficacy. Our previous research has showed that nonanalgetic dose of a cannabinoid type 2 (CB2) receptor agonist reduced morphine tolerance in cancer pain. A previous study showed the colocalization of CB2 and transient receptor potential vanilloid 1 (TRPV1) in human and rat dorsal root ganglia (DRG) sensory neurons. Whether coadministration of a CB2 receptor agonist and morphine could reduce TRPV1 expression in morphine­induced antinociception and tolerance in cancer pain is unclear. Therefore, we investigated the effects of coadministration of a CB2 receptor agonist AM1241 and morphine on TRPV1 expression and tolerance in cancer pain. Coadministration of AM1241 and morphine for 8 days significantly reduced morphine tolerance, as assessed by measuring paw withdrawal latency to a radiant heat stimulation, in Walker 256 tumor­bearing rats. Repeated morphine treatment for a period of 8 days induced upregulation of the TRPV1 protein expression levels in the DRG in the tumor­bearing rats, although no change in mRNA expression. Pretreatment with AM1241 reduced this morphine­induced upregulation of TRPV1 and the effect was reversed by the CB2 receptor antagonist AM630. Our findings suggest that coadministration of a CB2 receptor agonist AM1241 and morphine reduced morphine tolerance possibly through regulation of TRPV1 protein expression in the DRG in cancer pain.