Chrysomycin A Regulates Proliferation and Apoptosis of Neuroglioma Cells via the Akt/GSK-3β Signaling Pathway In Vivo and In Vitro

Glioblastoma (GBM) is a major type of primary brain tumor without ideal prognosis and it is therefore necessary to develop a novel compound possessing therapeutic effects. Chrysomycin A (Chr-A) has been reported to inhibit the proliferation, migration and invasion of U251 and U87-MG cells through the Akt/GSK-3β signaling pathway, but the mechanism of Chr-A against glioblastoma in vivo and whether Chr-A modulates the apoptosis of neuroglioma cells is unclear. The present study aims to elucidate the potential of Chr-A against glioblastoma in vivo and how Chr-A modulates the apoptosis of neuroglioma cells. Briefly, the anti-glioblastoma activity was assessed in human glioma U87 xenografted hairless mice. Chr-A-related targets were identified via RNA-sequencing. Apoptotic ratio and caspase 3/7 activity of U251 and U87-MG cells were assayed via flow cytometry. Apoptosis-related proteins and possible molecular mechanisms were validated via Western blotting. The results showed that Chr-A treatment significantly inhibits glioblastoma progression in xenografted hairless mice, and enrichment analysis suggested that apoptosis, PI3K-Akt and Wnt signaling pathways were involved in the possible mechanisms. Chr-A increased the apoptotic ratio and the activity of caspase 3/7 in U251 and U87-MG cells. Western blotting revealed that Chr-A disturbed the balance between Bax and Bcl-2, activating a caspase cascade reaction and downregulating the expression of p-Akt and p-GSK-3β, suggesting that Chr-A may contribute to glioblastoma regression modulating in the Akt/GSK-3β signaling pathway to promote apoptosis of neuroglioma cells in vivo and in vitro. Therefore, Chr-A may hold therapeutic promise for glioblastoma.

Chrysomycin A Inhibits the Proliferation, Migration and Invasion of U251 and U87-MG Glioblastoma Cells to Exert Its Anti-Cancer Effects

Chrysomycin A (Chr-A), an antibiotic from Streptomyces, is reported to have anti-tumor and anti-tuberculous activities, but its anti-glioblastoma activity and possible mechanism are not clear. Therefore, the current study was to investigate the mechanism of Chr-A against glioblastoma using U251 and U87-MG human cells. CCK8 assays, EdU-DNA synthesis assays and LDH assays were carried out to detect cell viability, proliferation and cytotoxicity of U251 and U87-MG cells, respectively. Transwell assays were performed to detect the invasion and migration abilities of glioblastoma cells. Western blot was used to validate the potential proteins. Chr-A treatment significantly inhibited the growth of glioblastoma cells and weakened the ability of cell migration and invasion by down regulating the expression of slug, MMP2 and MMP9. Furthermore, Chr-A also down regulated Akt, p-Akt, GSK-3β, p-GSK-3β and their downstream proteins, such as β-catenin and c-Myc in human glioblastoma cells. In conclusion, Chr-A may inhibit the proliferation, migration and invasion of glioblastoma cells through the Akt/GSK-3β/β-catenin signaling pathway.

ST2825, a Small Molecule Inhibitor of MyD88, Suppresses NF-κB Activation and the ROS/NLRP3/Cleaved Caspase-1 Signaling Pathway to Attenuate Lipopolysaccharide-Stimulated Neuroinflammation

Neuroinflammation characterized by microglia activation is the mechanism of the occurrence and development of various central nervous system diseases. ST2825, as a peptide-mimetic MyD88 homodimerization inhibitor, has been identified as crucial molecule with an anti-inflammatory role in several immune cells, especially microglia. The purpose of the study was to investigate the anti-neuroinflammatory effects and the possible mechanism of ST2825. Methods: Lipopolysaccharide (LPS) was used to stimulate neuroinflammation in male BALB/c mice and BV2 microglia cells. The NO level was determined by Griess Reagents. The levels of pro-inflammatory cytokines and chemokines were determined by ELISA. The expressions of inflammatory proteins were determined by real-time PCR and Western blotting analysis. The level of ROS was detected by DCFH-DA staining. Results: In vivo, the improved levels of LPS-induced pro-inflammatory factors, including TNF-α, IL-6, IL-1β, MCP-1 and ICAM-1 in the cortex and hippocampus, were reduced after ST2825 treatment. In vitro, the levels of LPS-induced pro-inflammatory factors, including NO, TNF-α, IL-6, IL-1β, MCP-1, iNOS, COX2 and ROS, were remarkably decreased after ST2825 treatment. Further research found that the mechanism of its anti-neuroinflammatory effects appeared to be associated with inhibition of NF-κB activation and down-regulation of the NLRP3/cleaved caspase-1 signaling pathway. Conclusions: The current findings provide new insights into the activity and molecular mechanism of ST2825 for the treatment of neuroinflammation.

TLR4-IN-C34 Inhibits Lipopolysaccharide-Stimulated Inflammatory Responses via Downregulating TLR4/MyD88/NF-κB/NLRP3 Signaling Pathway and Reducing ROS Generation in BV2 Cells

TLR4 signal activated by lipopolysaccharide (LPS) is involved in the pathological process of the central nervous system (CNS) diseases and the suppression of TLR4 signal may become an effective treatment. TLR4-IN-C34, a TLR4 inhibitor, is expected to become a candidate compound with anti-neuroinflammatory response. In the present study, the anti-neuroinflammatory effects and possible mechanism of TLR4-IN-C34 were investigated in BV2 microglia cells stimulated by LPS. The results showed that TLR4-IN-C34 decreased the levels of pro-inflammatory factors and chemokines including NO, TNF-α, IL-1β, IL-6, and MCP-1 in the supernatant of LPS-stimulated BV2 cells. Further research indicated that TLR4-IN-C34 suppressed the expression or phosphorylation levels of inflammatory proteins regarding TLR4/MyD88/NF-κB/NLRP3 signaling pathway. In addition, TLR4-IN-C34 reduced ROS production in BV2 cells after LPS treatment. In conclusion, our findings suggest that anti-neuroinflammatory activity of TLR4-IN-C34 may be interrelated to the inhibition of TLR4/MyD88/NF-κB/NLRP3 signaling pathway and reduction of ROS generation.

Chrysomycin A Attenuates Neuroinflammation by Down-Regulating NLRP3/Cleaved Caspase-1 Signaling Pathway in LPS-Stimulated Mice and BV2 Cells

Chrysomycin A (Chr-A), an antibiotic chrysomycin, was discovered in 1955 and is used to treat cancer and tuberculosis. In the present study, the anti-neuroinflammatory effects and possible mechanism of Chr-A in BALB/c mice and in BV2 microglia cells stimulated by lipopolysaccharide (LPS) were investigated. Firstly, the cortex tissues of mice were analyzed by RNA-seq transcriptome to identify differentially expressed genes (DEGs) regulated by Chr-A in LPS-stimulated mice. Inflammatory cytokines and inflammatory proteins were detected by enzyme-linked immunosorbent assay and Western blot. In RNAseq detection, 639 differential up-regulated genes between the control group and LPS model group and 113 differential down-regulated genes between the LPS model group and Chr-A treatment group were found, and 70 overlapping genes were identified as key genes for Chr-A against neuroinflammation. Subsequent GO biological process enrichment analysis showed that the anti-neuroinflammatory effect of Chr-A might be related to the response to cytokine, cellular response to cytokine stimulus, and regulation of immune system process. The significant signaling pathways of KEGG enrichment analysis were mainly involved in TNF signaling pathway, cytokine-cytokine receptor interaction, NF-κB signaling pathway, IL-17 signaling pathway and NOD-like receptor signaling pathway. Our results of in vivo or in vitro experiments showed that the levels of pro-inflammatory factors including NO, IL-6, IL-1β, IL-17, TNF-α, MCP-1, CXCL12, GM-CSF and COX2 in the LPS-stimulated group were higher than those in the control group, while Chr-A reversed those conditions. Furthermore, the Western blot analysis showed that its anti-neuroinflammation appeared to be related to the down-regulation of NLRP3/cleaved caspase-1 signaling pathway. The current findings provide new insights into the activity and molecular mechanisms of Chr-A for the treatment of neuroinflammation.

[Efficacy comparison between robot-assisted and laparoscopic surgery for mid-low rectal cancer: a prospective randomized controlled trial]

Objective: To compare the short- and long-term outcomes of robot-assisted and laparoscopic radical resection for mid-low rectal cancer. Methods: A prospective randomized controlled trial was conducted. A total of 130 patients with mid-low rectal cancer (inclusion criteria: age > 18 or ≤80 years old; pathological diagnosis of rectal adenocarcinoma by colonoscopy; distance from tumor to the anal verge ≤12 cm; no distant metastasis; cT1-3N0-1 or ycT1-3 after neoadjuvant radiotherapy and chemotherapy; suitable for laparoscopic and robotic surgery) at the Department of Colorectal Surgery of the First Affiliated Hospital of Nanchang University from October 2016 to September 2018 were prospectively enrolled. According to computer-generated random number method, patients were randomly divided into the robot group (n=66) and laparoscopy group (n=64), and underwent robot-assisted surgery or laparoscopic surgery respectively. Clinicopathological data of all the patients were collected and analyzed. The demographic parameters, short- and long-term outcomes were compared between two groups. Results: One patient in robot group whose postoperative sample was diagnosed as rectal adenoma by pathology was excluded. There were no statistically significant differences in age, sex, BMI, ASA classification, distance from tumor to the anal verge, serum CEA level, CA199 level between two groups (all P>0.05). Operations were successfully performed in all the patients without conversion to open operation. Robotic surgery was found to be associated with less intraoperative blood loss than laparoscopic surgery [(73.4±49.7) ml vs. (119.1±65.7) ml, t=-4.461, P<0.001], while there were no statistically significant differences in surgical procedures, operation time, time to first flatus, time to first liquid intake, time to removal of catheter or postoperative hospital stay between two groups (all P>0.05). Besides, there was no significant difference in the morbidity of postoperative complication between two groups [10.8% (7/65) vs. 12.5 (8/64), χ(2)=4.342, P=0.720]. The median number of harvested lymph node in the robot group and the laparoscopy group was 15.7±6.2 and 13.8±6.1 (t=1.724, P=0.087). There were no significant differences between two groups in tumor sample length, distance between proximal and distal resection margin, integrity grade of TME specimen, number of positive lymph nodes, postoperative pathological stage and tumor differentiation (all P>0.05). The distal resection margin of samples in two groups was all negative. One case in the robot group was found to have positive circumferential resection margin. The median follow up was 24 (9 to 31) months. In the robot group and the laparoscopy group, the 2-year overall survival rate was 95.4% and 90.6% respectively; the 2-year disease-free survival rate was 90.8% and 85.9% respectively, whose differences were not significant (both P>0.05). Conclusion: Robot-assisted radical resection for mid-low rectal cancer can achieve similar short-term and long-term outcomes of laparoscopic resection, while robot-assisted surgery can decrease blood loss during operation, leading to more precise practice in minimally invasive surgery.

[Key points and skills of assistant in robotic radical gastrectomy for gastric cancer]

An excellent assistant for robotic radical gastrectomy can play an important role in the operation, especially in a initial team. In robotic gastric cancer surgery, an excellent assistant should actively participate in the operation process, choose the appropriate trocar position according to patient's body habitus. Moreover, he should master various surgical instruments skillfully and switch instruments fluently to assist the surgeon to expose key parts during operation, and provide effective help in the operative details, so that the whole operation process can run more smoothly and the operation efficiency and quality will be greatly improved. The growth of the assistants needs constant practice and summary of experience. Meanwhile, the encouragement of the chief surgeon also plays a positive role in promoting the development of the assistants.

[Short-term clinical efficacy of robotic radical resection for high rectal cancer with transvaginal specimen extraction]

Objective: To explore the short-term clinical efficacy of robotic radical resection for high rectal cancer with transvaginal specimen extraction. Methods: A cohort study was carried out. The clinical data of consecutive patients with high rectal cancer who underwent robotic radical resection at the Department of General Surgery of The First Affiliated Hospital of Nanchang University from June 2017 to January 2018 were retrospectively analyzed. Inclusion criteria: (1) preoperative diagnosis of rectal cancer, and distance from tumor to anal margin≥10 cm undercolonoscopy; (2) T1-3 assessed by preoperative imaging examination, and no distant metastasis; (3) female, age≥50 years old, body mass index ≤ 30 kg/m(2); (4) without radiotherapy and chemotherapy before surgery; (5) implementation of robotic radical surgery for high rectal cancer. Fourteen female patients undergoing transvaginal removal of specimen without abdominal incision were included in the no incision group with age of (62.2±9.3) years old and distance from tumor to anal verge of (12.5±0.9) cm. As the match of 1:2, 28 simultaneous patients of high rectal cancer undergoing traditional robotic surgery (surgery interval <8 months) were enrolled to the control group, with age of (60.6±12.8) years old and distance from tumor to anal verge of (11.3±3.8) cm. Short-term efficacy and safty were compared between two groups. Follow-up ended in September 2018. Results: There was no significant difference in baseline data between the two groups (all P>0.05). Compared with the control group, the no incision group had longer operation time [(149.6±15.6) minutes vs. (130.9±12.9) minutes, t=-4.135, P<0.001], shorter time to postoperative flatus [(40.9 ±2.6) hours vs. (51.9±2.9) hours, t=12.049, P<0.001], lower pain score on the operation day and the first day after surgery (using Changhaipainstick) [(3.1±0.4) points vs. (4.6±0.7) points, t=7.458, P<0.001; (2.5±0.3) points vs. (3.3±0.5) points, t=6.142, P<0.001], shorter time to ground activity [(15.6±2.0) hours vs. (24.3±2.5) hours, t=11.102, P=0.030], and shorter postoperative hospital stay [(6.1±0.8) days vs. (7.2±1.3) days, t=2.806, P=0.008], whose differences were statistically significant. There were no significant differences in intraoperative blood loss, proportion of postoperative analgesia patients, and complication within 30 days after surgery (all P>0.05). In the no incision group and the control group,the tumor size was (3.1±0.4) cm and (3.6±0.9) cm, the proximal margin distance was (9.1±1.5) cm and (9.8±1.5) cm, the distal margin distance was (4.3±0.4) cm and (4.5±0.4) cm, the number of harvested lymph node was 15.8±2.4 and 15.2 ± 2.5, and the number of positive lymph node was 0.6±1.3 and 1.1±2.4, respectively, whose differences were not statistically significant (all P>0.05). The mean followed-up period was 10 months (7-14 months) in the no incision group, and 14 months (10-18 months) in the control group. No local recurrence and distant metastasis were found in both groups. Conclusion: Robotic radical resection for high rectal cancer with transvaginal specimen extraction is safe and feasible with advantages of rapid postoperative recovery, less postoperative pain and short hospital stay.

Identification of novel compound heterozygous RECQL4 mutations and prenatal diagnosis of Baller-Gerold syndrome: a case report

Birth defects are structural and/or functional malformations present at birth that cause physical or mental disability and are important public health problems. Our study was aimed at genetic analysis and prenatal diagnosis of congenital anomalies to understand the cause of certain birth defects. Karyotypes and array-comparative genomic hybridization (aCGH) were performed on a pregnant woman, surrounding amniotic fluid, and her husband. A short-stature panel genetic test was conducted in accordance with the phenotype of the fetus. Following examination, it was determined that the karyotype and aCGH results were normal. The RECQL4 gene in the fetus showed compound heterozygous mutations, and each parent was found to be a carrier of one of the mutations. The two heterozygous mutations (c.2059-1G>C and c.2141_2142delAG) were detected in the RECQL4 (NM_004260) gene in the fetus; therefore, the fetus was predicted to have Baller-Gerold syndrome. These two mutations have not previously been reported. In addition, these results identified a 25% risk of the parents having a sec-ond conceptus with this congenital disease. Therefore, prenatal genetic diagnosis was highly recommended for future pregnancies.

Effects of bee venom peptidergic components on rat pain-related behaviors and inflammation

To identify the active components of honeybee venom in production of inflammation and pain-related behaviors, five major peptidergic subfractions were separated, purified and identified from the whole honeybee venom. Among them, four active peptidergic components were characterized as apamin, mast-cell degranulating peptide (MCDP), phospholipase A(2) (PLA(2))-related peptide and melittin, respectively. All five subfractions were effective in production of local inflammatory responses (paw edema) in rats although the efficacies were different. Among the five identified subfractions, only MCDP, PLA(2)-related peptide and melittin were able to produce ongoing pain-related behaviors shown as paw flinches, while only apamin and melittin were potent to produce both thermal and mechanical hypersensitivity. As shown in our previous report, melittin was the most potent polypeptide in production of local inflammation as well as ongoing pain and hypersensitivity. To further explore the peripheral mechanisms underlying melittin-induced nociception and hypersensitivity, a single dose of capsazepine, a blocker of thermal nociceptor transient receptor potential vanilloid receptor 1, was treated s.c. prior to or after melittin administration. The results showed that both pre- and post-treatment of capsazepine could significantly prevent and suppress the melittin-induced ongoing nociceptive responses and thermal hypersensitivity, but were without influencing mechanical hypersensitivity. The present results suggest that the naturally occurring peptidergic substances of the whole honeybee venom have various pharmacological potencies to produce local inflammation, nociception and pain hypersensitivity in mammals, and among the five identified reverse-phase high pressure liquid chromatography subfractions (four polypeptides), melittin, a polypeptide occupying over 50% of the whole honeybee venom, plays a central role in production of local inflammation, nociception and hyperalgesia or allodynia following the experimental honeybee's sting. Peripheral transient receptor potential vanilloid receptor 1 is likely to be involved in melittin-produced ongoing pain and heat hyperalgesia, but not mechanical hyperalgesia, in rats.