The Prognostic and Therapeutic Value of PD-L1 in Glioma

Glioma is the most common type of primary brain tumors. After standard treatment regimen (surgical section, radiotherapy and chemotherapy), the average survival time remains merely around 14 months for glioblastoma (grade IV glioma). Recent immune therapy targeting to the immune inhibitory checkpoint axis, i.e., programmed cell death protein 1 (PD-1) and its ligand PD-L1 (i.e., CD274 or B7-H1), has achieved breakthrough in many cancers but still not in glioma. PD-L1 is considered a major prognostic biomarker for immune therapy in many cancers, with anti-PD-1 or anti-PD-L1 antibodies being used. However, the expression and subcellular distribution of PD-L1 in glioma cells exhibits great variance in different studies, severely impairing PD-L1's value as therapeutic and prognostic biomarker in glioma. The role of PD-L1 in modulating immune therapy is complicated. In addition, endogenous PD-L1 plays tumorigenic roles in glioma development. In this review, we summarize PD-L1 mRNA expression and protein levels detected by using different methods and antibodies in human glioma tissues in all literatures, and we evaluate the prognostic value of PD-L1 in glioma. We also summarize the relationships between PD-L1 and immune cell infiltration in glioma. The mechanisms regulating PD-L1 expression and the oncogenic roles of endogenous PD-L1 are discussed. Further, the therapeutic results of using anti-PD-1/PD-L1 antibodies or PD-L1 knockdown are summarized and evaluated. In summary, current results support that PD-L1 is not only a prognostic biomarker of immune therapy, but also a potential therapeutic target for glioma.

[Prognostic significance of combined TERT and IDH gene mutation analysis in diffusely infiltrating gliomas]

Objective: To investigate the status and prognostic significance of TERT and IDH1/2 genes mutations in diffusely infiltrating gliomas. Methods: Hot spot mutations of TERT and IDH1/2 genes were detected by DNA sequencing in 236 cases of gliomas at West China Hospital from 2012 to 2016, including pilocytic astrocytoma (WHO grade Ⅰ, 16 cases), diffuse astrocytoma and oligodendroglioma (WHO grade Ⅱ, 89 cases), anaplastic astrocytoma and oligodendroglioma (WHO grade Ⅲ, 72 cases) and glioblastoma (WHO grade Ⅳ, 59 cases). The prognostic significance of TERT and IDH1/2 hot spot mutations was evaluated. Results: No IDH or TERT mutations were detected in pilocytic gliomas. TERT promoter mutation frequency was higher in patients aged ≥40 years(60.8%, 93/153) than in patients aged <40 years (32.8%, 22/67; P<0.01). TERT promoter mutation rate was also significantly higher in oligodendroglioma (87.5% , 56/64) than that in astrocytoma(37.8%, 59/156; P<0.01). Young age (<40 years), oligodendroglioma and IDH1 mutation were favorable prognostic factors for diffusely infiltrating astrocytic and oligodendroglial tumors. TERT mutation alone was not of prognostic significance. Diffusely infiltrating astrocytic and oligodendroglial tumors were divided into four molecular subtypes according to TERT and IDH1 mutation status: IDH(+ )/TERT(+ ), IDH(+ )/TERT(-), IDH(-)/TERT(-) and IDH(-)/TERT(+ ). There was significant prognostic difference among the 4 subtypes. Conclusions: Combined IDH and TERT gene mutation analysis may be useful for prognostic subgrouping. Notably, IDH1 wild-type cases can be further subdivided into TERT(+ ) or (-) subgroups with significant prognostic difference.

[Advances in the research of biomechanical effects of negative-pressure wound therapy in promoting wound healing]

Recently, researchers have focused on the micro-mechano-environment and the resulting mechanical cues which can regulate the morphology, structure, and function of cells. As a novel mechanotherapy, negative-pressure wound therapy (NPWT) has revolutionized the treatment of acute and chronic wounds. The effects of mechanics in use of NPWT has been noticed by researchers, and sporadic results have been reported, while the mechanisms of mechanosensitivity and mechanotransduction in affecting cell behaviors and promoting wound healing haven't been elucidated yet. In this article, we review the progress about the relevant mechanical forces of NPWT and the mechanical effects on major repairing cells involved in wound healing, in order to provide references for the better understanding of mechanobiology of NPWT to better wound healing.

PD-L1 confers glioblastoma multiforme malignancy via Ras binding and Ras/Erk/EMT activation

Glioblastoma multiforme (GBM) is the most aggressive primary brain tumor due to the lack of effective therapeutic drugs. Cancer therapy targeting programmed cell death protein 1 (PD-1) or programmed death ligand-1 (PD-L1) is of revolutionary. However, the role of intrinsic PD-L1, which determines immune-therapy outcomes, remains largely unclear. Here we demonstrated an oncogenic role of PD-L1 via binding and activating Ras in GBM cells. RNA-sequencing transcriptome data revealed that PD-L1 significantly altered gene expression enriched in cell growth/migration/invasion pathways in human GBM cells. PD-L1 overexpression and knockout or knockdown demonstrated that PD-L1 promoted GBM cell proliferation and migration in vitro and in vivo. Mechanistically, PD-L1 prominently activated epithelial mesenchymal transition (EMT) process in a MEK/Erk- but not PI3K/Akt-dependent manner. Further, we identified intracellular interactions of PD-L1 and H-Ras, which led to Ras/Erk/EMT activation. Finally, we demonstrated that PD-L1 overexpression promoted while knockdown abolished GBM development and invasion in orthotopic GBM models of rodents. Taken together, we found that intracellular PD-L1 confers GBM cell malignancy and aggressiveness via binding Ras and activating the downstream Erk-EMT signaling. Thus, these results shed important insights in improving efficacy of immune therapy for GBM as well as other malignant tumors.

[Experimental study on the effect of Yiqi Wenyang Decoction on nasal mucosa infiltration of NK cells in mice with allergic rhinitis]

Objective: To observe the effect of Yiqi Wenyang Decoction on the infiltration and activation of NK cells in nasal mucosa of mouse model with allergic rhinitis (AR), and to explore the potential mechanism for effective intervention of AR with Yiqi Wenyang Decoction. Methods: Fourty-eight mice were randomly divided into blank group, model group, low, medium and high dose of Yiqi Wenyang Decoction group and Cetirizine group, with 8 rats in each group. After modeling of AR, the model group was filled with 0.9% sodium chloride solution. Yiqi Wenyang Decoction groups of each dose were given different concentrations of Yiqi Wenyang Decoction water extract, while the Cetirizine group was given aqueous solution of Cetirizine. The behavior, morphological changes of nasal mucosa and infiltration of NK cells in nasal mucosa were observed. The levels of IL-4 and INF-γ in nasal lavage fluid were measured. Besides, the drug safety was observed by acute toxicity test. Results: In the respect of behavioral scoring, middle and high dose of Yiqi Wenyang Decoction group were superior to the model group (number of sneezing: q value was 7.189, 8.748, respectively; number of scratching nose: q value was 12.074, 14.560, respectively; all P<0.05). In middle and high dose of Yiqi Wenyang Decoction group, the infiltration of NK cells and nasal lavage fluid IL-4 levels were lower than those in model group (IOD: q value was 10.073, 12.322, respectively; IOD/Area: q value was 10.954, 14.073, respectively; IL-4: q value was 4.705, 6.801, respectively; all P<0.05). There was no significant difference in nasal lavage fluid of INF-γ among each group (Fv=1.166, P>0.05). In acute toxicity test, no obvious poisoning symptoms and death occurred in mice. Conclusion: Yiqi Wenyang Decoction can control the nasal symptom, reduce the local NK cell infiltration of nasal mucosa and inhibit the expression of the 2-type cytokines released by NK cells, which may be related with the potential mechanism of effective intervention of AR with Yiqi Wenyang Decoction.

Piperlongumine suppresses bladder cancer invasion via inhibiting epithelial mesenchymal transition and F-actin reorganization

Piperlongumine (PL), a natural alkaloid isolated from longer pepper plants, is recently found to be a potent selective anti-cancer compound. We first tested its anti-cancer effects on bladder cancer, the fifth most common and aggressive cancer worldwide, to further explore the therapeutic spectrum and molecular mechanisms of PL. PL significantly suppressed bladder cancer cell proliferation, the transition of G2/M phase to next phase, migration/invasion in vitro and bladder cancer growth/development in vivo. PL markedly elevated reactive oxygen species (ROS) and the administration of antioxidants abolished PL induced cell proliferation inhibition, G2/M phase arrest and migration suppression on bladder cancer cells. In vivo studies demonstrated that PL inhibited epithelial mesenchymal transition with profoundly decreased level of Slug, β-catenin, ZEB1 and N-Cadherin. Further, we first reported PL effects on cytoskeleton with prominently reduced lamellipodia formation and decreased F-actin intensity in bladder cancer cells. Taken together, our results first revealed that PL suppressed bladder cancer proliferation and migration in vivo and in vitro, suggesting novel mechanism underlying PL's anti-cancer effect and providing a new anticancer drug strategy for bladder cancer therapy.

Identification of repaglinide as a therapeutic drug for glioblastoma multiforme

Glioblastoma multiforme (GBM) is a highly aggressive brain tumor with a median survival time of only 14 months after treatment. It is urgent to find new therapeutic drugs that increase survival time of GBM patients. To achieve this goal, we screened differentially expressed genes between long-term and short-term survived GBM patients from Gene Expression Omnibus database and found gene expression signature for the long-term survived GBM patients. The signaling networks of all those differentially expressed genes converged to protein binding, extracellular matrix and tissue development as revealed in BiNGO and Cytoscape. Drug repositioning in Connectivity Map by using the gene expression signature identified repaglinide, a first-line drug for diabetes mellitus, as the most promising novel drug for GBM. In vitro experiments demonstrated that repaglinide significantly inhibited the proliferation and migration of human GBM cells. In vivo experiments demonstrated that repaglinide prominently prolonged the median survival time of mice bearing orthotopic glioma. Mechanistically, repaglinide significantly reduced Bcl-2, Beclin-1 and PD-L1 expression in glioma tissues, indicating that repaglinide may exert its anti-cancer effects via apoptotic, autophagic and immune checkpoint signaling. Taken together, repaglinide is likely to be an effective drug to prolong life span of GBM patients.

[Vibrant soundbridge implantation of congenital atresia of oval window(with summary of nine cases]

Objective:To investigate the surgical effects of round window implantation of vibrant soundbridge(VSB)for patients with congenital oval window atresia.Method:Retrospectively analyze the clinical information of 9 cases of congenital oval window atresia as well as the pre-and post-operative hearing and speech results. Three of them had undergone or attempted the vestibulotomy but obtained poor results. All cases underwent round window implantation of VSB. Result:All patients obtained an improvement of 21-33 dBHL after implantation. In the speech recognition rate test, the average increase of disyllabic words was 62%, and 60% in the sentence test. During the follow-up of 51 months in average, 2 cases had a decline of auditory benefit and finally 1 case regained the improvement after reoperation. Conclusion:Round window implantation can get a fairly good result in congenital oval windows atresia cases.

Advances in Hypoxia-Mediated Mechanisms in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the fifth most common and the third most deadly malignant tumor worldwide. Hypoxia and related oxidative stress are heavily involved in the process of HCC development and its therapies. However, direct and accurate measurement of oxygen concentration and evaluation of hypoxic effects in HCC prove difficult. Moreover, the hypoxia-mediated mechanisms in HCC remain elusive. Here, we summarize recent major evidence of hypoxia in HCC lesions shown by measuring partial pressure of oxygen (pO₂), the clinical importance of hypoxic markers in HCC, and recent advances in hypoxia-related mechanisms and therapies in HCC. For the mechanisms, we focus mainly on the roles of oxygen-sensing proteins (i.e., hypoxia-inducible factor and neuroglobin) and hypoxia-induced signaling proteins (e.g., matrix metalloproteinases, high mobility group box 1, Beclin 1, glucose metabolism enzymes, and vascular endothelial growth factor). With respect to therapies, we discuss mainly YQ23, sorafenib, 2-methoxyestradiol, and celastrol. This review focuses primarily on the results of clinical and animal studies.

[The application of mandarin acceptable noise level and COS in hearing aid fitting for presbyacusis]

Objective:The purpose of this study was to inquiry into the application of mandarin acceptable noise level(M-ANL) and client oriented scale of improvement in evaluation of hearing aid fitting for presbyacusis. Method:Thirty-two adults with presbycusis who used the hearing aid for the first time were selected for the study. M-ANL tests were done prior to the hearing aid fitting. Six weeks later, these patients were asked to fill in questionnaire of client oriented scale of improvement (COSI).The subjects were divided into 3 groups according to the time of hearing aid using in their daily lives: less than one hour per day, 1 to 4 hours per day and more than 4 hours per day. The relativity of M-ANL and the score of COSI were compared. Result:①There were significant differences of the M-ANL among 3 groups(P<0.05); ②The scores of COSI of group 1(less than one hour per day) was lower than group 2(1 to 4 hours per day), while there were no significant differences between the scores of group 2(1 to 4 hours per day) and group 3(more than 4 hours per day); ③There was good correlation between the score of M-ANL and COSI. Conclusion:M-ANL can forecast the satisfaction of hearing aids fitting. And COSI can play an effective role in outcome measurement.

[Evaluation of the level of urinary cysteinyl leukotriene E4 in diagnosis of bronchopulmonary dysplasia in premature infants]

OBJECTIVE

To explore the correlation of urinary cysteinyl leukotriene E4 (CysLTE4) and diagnosis of bronchopulmonary dysplasia (BPD) in premature infants.

METHOD

One hundred and fifty-eight newborn infants were consecutively admitted to the neonatal intensive care units of First Affiliated Hospital of Nanjing Medical University from November 2014 to October 2015.The infants were divided into 3 groups according to the diagnosis on discharge.Sixty-one term infants were classified as having no pulmonary diseases, 52 premature infants were classified as without BPD, and 45 premature infants with BPD were diagnosed at 28 d after birth.Urinary CysLTE4 levels of newborns within 3 days after birth were measured in a blinded way by enzyme- linked immunosorbent assay and were compared among 3 groups, and were evaluated for the diagnostic value and the correlation of gestational age and birth weight.Statistical analysis was performed using correlation analysis, one-way analysis of variance and χ(2) test etc.

RESULT

In infants with BPD, the mean urinary CysLTE4 level was (191.0±29.3) ng/L which significantly higher than the premature group without BPD ((164.1±22.7) ng/L) and term infant group ((151.6±41.9) ng/L, F=18.70, P<0.05). Urinary CysLTE4 level within 3 days of life in newborn inversely correlated with gestational age and birth weight (Pearson=-0.33, -0.38, P<0.01). The area under the curve was 0.78, 95%CI: 0.70-0.86, P<0.01, when cutoff was 187.7 ng/L, with Youden index 0.59, sensitivity 77.8% and specificity 81.4%, respectively.

CONCLUSION

Urinary CysLTE4 level is up-regulated in BPD infants within early days of life which may be a useful biomarker of early diagnoses of BPD.

[Clinical analysis of the character and prognostic factors of 23 cases of mantle cell lymphoma]

OBJECTIVE

To investigate the clinical characteristics and prognostic factors of mantle cell lymphoma (MCL) patients.

METHODS

The clinical data of 23 MCL patients were retrospectively analyzed. Immunohistochemical stain was performed to detect the protein expressions of Mcl-1, pNF-κB p65 and 14-3-3ζ of MCL patients to analyze its prognostic factors.

RESULTS

Among 23 MCL patients, there were 17(73.9%) patients with IPI 0-2 (low risk group) and 6(26.1%) patients with IPI 3-4. Only the rate of 2y-progression-free survival (PFS) of group IPI 0-2 was superior to that of group IPI 3-4 patients (47.1% vs 0, P=0.049); There were 16 (69.5%) patients with MIPI < 5.7, whose rates of overall response rate (ORR), 2y overall survival (OS) and PFS were better than those of the ones with MIPI ≥ 5.7(ORR: 81.3% vs 33.3% P=0.032; OS: 68.8% vs 16.7% P=0.041; PFS: 50% vs 0, P=0.040 respectively). The rates of ORR, 2y-OS and 2y-PFS (100.0%, 80.0% and 70.0%) of patienets received regimen R+CHOP(E) were all superior to those (38.5%, 30.8% and 7.7%) of ones received regimen CHOP(E) (P=0.002, P= 0.024, P=0.003, respectively). Among 12 patients, 2 out of 6 cases with Mcl-1 positive expression achieved good response (CR+PR) and 2y-OS, 1 case 2y-PFS; All 6 cases with Mcl-1 negative expression achieved good response (CR+PR) and 2y-OS, 5 cases 2y-PFS. 3 out of 6 cases with pNF-κB p65 positive expression achieved good response (CR+PR) and 2y-OS, 1 case 2y-PFS; 5 out of 6 cases with pNF-κB p65 negative expression achieved good response (CR+ PR) and 2y-OS/PFS. 5 out of 8 cases with 14-3-3ζ positive expression achieved good response (CR+PR), 4 cases 2y-OS, and 3 cases 2y-PFS. 3 out of 4 cases with 14-3-3ζ negative expression achieved CR, 4 cases 2y-OS, and 3 cases 2y-PFS.

CONCLUSION

MCL patients had high heterogeneity. MIPI has better prognostic significance than IPI. R+CHOP(E) as first line treatment improved the rates of OS/PFS. The expressions of Mcl-1, pNF-κB p65 and 14-3-3ζ proteins in MCL might be related to prognosis.

[Cortical auditory evoked potentials in congenital hearing impaired children with cochlear implants]

OBJECTIVE

By investigating the auditory cortical evoked potential in congenital hearing impaired children with cochlear implants, the association between central auditory development and the age of implantation was studied.

METHODS

P1-N1-P2 were recorded in 110 profound hearing impaired children, aged from 12 to 80 months old and being implanted with cochlear implants before the age of 5 years. Their implant using time ranged from just at the switch-on to 48 months. The stimuli were /m/, /t/, /g/, presented at 65 dB SPL in sound field. The presence rate of each wave was obtained and the relationship between P1 latency and implant age, the time of speech processor switch-on were analyzed.

RESULTS

The presence rate of P1, N1 and P2 was 66.4%, 15.5% and 12.7%, respectively. The presence of P1 was significantly higher than that of N1(χ(2)=228.542, P=0.00)and P2(χ(2)=257.438, P=0.00). There was no significant difference of P1 presence rate elicited by /m/, /t/ and /g/(64.1%, 66.9% and 68.3%, χ(2)=0.589, P=0.75). There existed no significant difference either among P1 latency(P=0.22)or amplitude(P=0.09) elicited by /m/, /t/ and /g/. There was significant difference between the implant age before and after 42-month-old regarding the proportion that entered the age-appropriate normal P1 latency range(P=0.02). No significant difference was found among groups of implant using time of 1, 2, 3 and 4 years in aspect of the proportion that entered the age-appropriate normal P1 latency range(P=1.00).

CONCLUSIONS

Compared with implanted after the age of 42-month-old children with prelingual hearing impairment younger than 5 years old, the ones implanted before 42-month-old have more chance for normal development for central auditory system. Once implanted before 42-month-old, the cortical auditory system restored its normal development as early as 1 year after implantation.

Piperlongumine selectively kills hepatocellular carcinoma cells and preferentially inhibits their invasion via ROS-ER-MAPKs-CHOP

Hepatocellular carcinomas (HCC) are highly malignant and aggressive tumors lack of effective therapeutic drugs. Piperlongumine (PL), a natural product isolated from longer pepper plants, is recently identified as a potent cytotoxic compound highly selective to cancer cells. Here, we reported that PL specifically suppressed HCC cell migration/invasion via endoplasmic reticulum (ER)-MAPKs-CHOP signaling pathway. PL selectively killed HCC cells but not normal hepatocytes with an IC50 of 10-20 µM while PL at much lower concentrations only suppressed HCC cell migration/invasion. PL selectively elevated reactive oxygen species (ROS) in HCC cells, which activated or up-regulated downstream PERK/Ire 1α/Grp78, p38/JNK/Erk and CHOP subsequently. Administration of antioxidants completely abolished PL's effects on cell death and migration/invasion. However, pharmacological inhibition of ER stress-responses or MAPKs signaling pathways with corresponding specific inhibitors only reversed PL's effect on cell migration/invasion but not on cell death. Consistently, knocking-down of CHOP by RNA interference only reversed PL-suppressed HCC cell migration. Finally, PL significantly suppressed HCC development and activated the ER-MAPKs-CHOP signaling pathway in HCC xenografts in vivo. Taken together, PL selectively killed HCC cells and preferentially inhibited HCC cell migration/invasion via ROS-ER-MAPKs-CHOP axis, suggesting a novel therapeutic strategy for the highly malignant and aggressive HCC clinically.

Ischemia preconditioning protects astrocytes from ischemic injury through 14-3-3γ

Stroke is a leading cause of death and disability, and new strategies are required to reduce neuronal injury and improve prognosis. Ischemia preconditioning (IPC) is an intrinsic phenomenon that protects cells from subsequent ischemic injury and might provide promising mechanisms for clinical treatment. In this study, primary astrocytes exhibited significantly less cell death than control when exposed to different durations of IPC (15, 30, 60, or 120 min). A 15-min duration was the most effective IPC to protect astrocytes from 8-hr-ischemia injury. The protective mechanisms of IPC involve the upregulation of protective proteins, including 14-3-3γ, and attenuation of malondialdehyde (MDA) content and ATP depletion. 14-3-3γ is an antiapoptotic intracellular protein that was significantly upregulated for up to 84 hr after IPC. In addition, IPC promoted activation of the c-Jun N-terminal kinase (JNK), extracellular signal-related kinase (ERK)-1/2, p38, and protein kinase B (Akt) signaling pathways. When JNK was specifically inhibited with SP600125, the upregulation of 14-3-3γ induced by IPC was almost completely abolished; however, there was no effect on ATP or MDA levels. This suggests that, even though both energy preservation and 14-3-3γ up-regulation were turned on by IPC, they were controlled by different pathways. The ERK1/2, p38, and Akt signaling pathways were not involved in the 14-3-3γ upregulation and energy preservation. These results indicate that IPC could protect astrocytes from ischemia injury by inducing 14-3-3γ and by alleviating energy depletion through different pathways, suggesting multiple protection of IPC and providing new insights into potential stroke therapies.

Piperlongumine inhibits migration of glioblastoma cells via activation of ROS-dependent p38 and JNK signaling pathways

Piperlongumine (PL) is recently found to kill cancer cells selectively and effectively via targeting reactive oxygen species (ROS) responses. To further explore the therapeutic effects of PL in cancers, we investigated the role and mechanisms of PL in cancer cell migration. PL effectively inhibited the migration of human glioma (LN229 or U87 MG) cells but not normal astrocytes in the scratch-wound culture model. PL did not alter EdU(+)-cells and cdc2, cdc25c, or cyclin D1 expression in our model. PL increased ROS (measured by DCFH-DA), reduced glutathione, activated p38 and JNK, increased IκBα, and suppressed NFκB in LN229 cells after scratching. All the biological effects of PL in scratched LN229 cells were completely abolished by the antioxidant N-acetyl-L-cysteine (NAC). Pharmacological administration of specific p38 (SB203580) or JNK (SP600125) inhibitors significantly reduced the inhibitory effects of PL on LN229 cell migration and NF κ B activity in scratch-wound and/or transwell models. PL prevented the deformation of migrated LN229 cells while NAC, SB203580, or SP600125 reversed PL-induced morphological changes of migrated cells. These results suggest potential therapeutic effects of PL in the treatment and prevention of highly malignant tumors such as glioblastoma multiforme (GBM) in the brain by suppressing tumor invasion and metastasis.

Association between the c.910A>G genetic variant of the XRCC1 gene and susceptibility to esophageal cancer in the Chinese Han population

Esophageal cancer (EC) is a common malignancy worldwide. The X-ray repair cross-complementing 1 gene (XRCC1) is one of the most important candidate genes for influencing susceptibility to EC. This study aimed to investigate the effect of XRCC1 genetic variants on susceptibility to EC. A total of 383 EC patients (males: 239, females: 144, mean age: 56.62) and 387 cancer-free controls (males: 251, females: 136, mean age: 58.23) were enrolled in this study. The c.910A>G genetic variant of the XRCC1 gene was determined by polymerase chain reaction-restriction fragment length polymorphism and DNA sequencing methods. The allele and genotype frequencies indicated statistical differences between EC patients and cancer-free controls. The c.910A>G genetic variant was statistically associated with increased susceptibility to EC [GG vs AA: odds ratio (OR)=1.79, 95% confidence interval (CI)=1.12-2.86, P=0.014; GG vs AG/AA: OR=1.76, 95%CI=1.13-2.75, P=0.013; G vs A: OR=1.25, 95%CI=1.01-1.55, P=0.041]. The allele G and genotype GG could contribute to the increased susceptibility to EC. Our findings suggest that the c.910A>G genetic variant is associated with susceptibility to EC in the Chinese Han population, and might be used as a molecular marker for detecting susceptibility to EC.

Piperlongumine selectively kills glioblastoma multiforme cells via reactive oxygen species accumulation dependent JNK and p38 activation

Piperlongumine (PL), a natural alkaloid isolated from the long pepper, may have anti-cancer properties. It selectively targets and kills cancer cells but leaves normal cells intact. Here, we reported that PL selectively killed glioblastoma multiforme (GBM) cells via accumulating reactive oxygen species (ROS) to activate JNK and p38. PL at 20μM could induce severe cell death in three GBM cell lines (LN229, U87 and 8MG) but not astrocytes in cultures. PL elevated ROS prominently and reduced glutathione levels in LN229 and U87 cells. Antioxidant N-acetyl-L-cysteine (NAC) completely reversed PL-induced ROS accumulation and prevented cell death in LN229 and U87 cells. In LN229 and U87 cells, PL-treatment activated JNK and p38 but not Erk and Akt, in a dosage-dependent manner. These activations could be blocked by NAC pre-treatment. JNK and p38 specific inhibitors, SB203580 and SP600125 respectively, significantly blocked the cytotoxic effects of PL in LN229 and U87 cells. Our data first suggests that PL may have therapeutic potential for one of the most malignant and refractory tumors GBM.

Neuroglobin, a novel intracellular hexa-coordinated globin, functions as a tumor suppressor in hepatocellular carcinoma via Raf/MAPK/Erk

Hypoxia and oxidative stress are critical factors in carcinogenesis and exist throughout cancer development; however, the underlying mechanisms are far from clear. Here, for the first time to our knowledge, we reported that neuroglobin (Ngb), an intracellular hexa-coordinated globin serving as an oxygen/reactive oxygen species (ROS) sensor, functions as a tumor suppressor in hepatocelluar carcinoma (HCC). Ngb protein and mRNA expression were significantly down-regulated in tumor tissues, compared with its adjacent non-tumor tissues of human HCC samples and normal liver tissues. Knock-down of Ngb by RNA interference promoted human HCC cell line (HepG2) growth and proliferation, G0/G1-S transition in vitro, and tumor growth in vivo. On the contrary, overexpression of Ngb suppressed HepG2 cell growth and proliferation, G0/G1-S transition, colony formation in vitro, and tumorigenicity in vivo. These results established a tumor suppressor function of Ngb in HCC. The underlying mechanisms were further investigated. Overexpression of Ngb suppressed Raf/MEK/extracellular signal-regulated kinase (Erk), whereas knockdown of Ngb enhanced Raf/MEK/Erk activation in HepG2 cells in vitro and in vivo. Glutathione S-transferase pull-down showed that Ngb interacted with c-Raf-1 in HepG2 cells. Overexpression of Ngb suppressed serum- and H₂O₂-stimulated Erk activation in HepG2 cells. Pharmacological inhibition of Erk activation abolished the proliferative effect of Ngb knockdown in HepG2 cells. Mutation of Ngb at its oxygen-binding site (H64L) abolished the inhibitory effects of Ngb on Erk activation and HepG2 cell proliferation. Therefore, we propose that Ngb controls HCC development by linking oxygen/ROS signals to oncogenic Raf/mitogen-activated protein kinase (MAPK)/Erk signaling. Our data suggest that neuroglobin could be a new target for cancer therapy.

Tritium release during nuclear power operation in China

Overviews were evaluated of tritium releases and related doses to the public from airborne and liquid effluents from nuclear power plants on the mainland of China before 2009. The differences between tritium releases from various nuclear power plants were also evaluated. The tritium releases are mainly from liquid pathways for pressurised water reactors, but tritium releases between airborne and liquid effluents are comparable for heavy water reactors. The airborne release from a heavy water reactor is obviously higher than that from a pressurised water reactor.

Analysis of 13 cases of venous compromise in 178 radial forearm free flaps for intraoral reconstruction

The purpose of this study was to analyse the causes of venous compromise and flap failure in radial forearm free flap (RFFF) surgery for intraoral reconstruction. One hundred seventy-eight RFFF reconstructions were reviewed retrospectively for intraoral defects. Of the 13 flaps with venous obstruction, 9 flaps were salvaged, and 4 were lost, with a salvage rate of 69.2%. Eleven venous occlusions occurred within the first 72h. The main reasons for venous failure were mechanical obstruction or technical errors due to inadequate pedicle length and geometry, inadequate venous drainage, compression and kinking of the vein. The main cause of failure for oropharynx reconstruction was unrecognized vascular events due to the lack of reliable monitoring for buried flap. Oozing of dusky blood from the flap margin may be directly related to venous congestion in the early postoperative period and a late indication of a change in skin colour. In conclusion, a thorough operative plan, including carefully selected drainage vein for the flap and recipient vessels, adequate pedicle length and geometry, precise surgical technique, avoidance of haematoma, and expert monitoring of buried flaps may improve the success rate of RFFF transfer in intraoral reconstruction.

The biomimetic immunoassay based on molecularly imprinted polymer: a comprehensive review of recent progress and future prospects

Immunoassay, based on a selective affinity of the biological antibody for its antigen, is one of the most usual analytical methods in food safety and environmental chemistry. However, it presents several drawbacks because of the nature of the antibody. Molecular imprinting technique, due to its high selectivity and stability, ease of preparation and low cost, has shown great potential in producing artificial antibodies in biomimetic immunoassays. This article focuses on the recent states, advantages, current problems and outlooks of molecularly imprinted radio, fluoro, enzyme-linked and chemiluminescent immunoassays, and biomimetic immunosensor, with special emphasis on the challenges in developing biomimetic enzyme-linked immunosorbent assays (BELISAs). The biomimetic immunoassay method will provide an important new analysis platform in food safety, although the sensitivity and specificity is relatively low.

PRACTICAL APPLICATION

As a new simple analysis method, the biomimetic immunoassay has attractive prospect, although some limitations were existed in real-sample assay. In this critical review, some promising solutions for overcoming its drawbacks were put forward, which may promote the more quick development and extensive application of this method in food safety.

Fabrication and characterization of elastomeric polyester/carbon nanotubes nanocomposites for biomedical application

A novel biodegradable polymer elastomer nanocomposite composing of poly(1,8-octanediol-citrate) (POC) polymer matrix and carbon nanotubes (CNTs) additive was successfully fabricated and systematically investigated using Fourier transform infrared (FT-IR), X-ray diffractometer (XRD), differential scanning calorimetry (DSC), tensile test, incubation and cytotoxicity tests. It was found that the addition of CNTs in POC elastomer did not result in any noticeable change in its chemical structure and the amorphous state. However, the tensile strength and elongation at break were greatly improved by the addition of CNTs in POC polymer matrix. It revealed that the swelling ratio and percentage of weight loss of POC/CNTs nanocomposite were lower, compared with the pure POC material. Moreover, the adsorption amount of bovine serum albumin (BSA) increased with an increase of the CNTs mass content in POC matrix revealing the enhanced hydrophilicity of POC/CNTs nanocomposites contributed by the carboxyl of the CNTs. Additionally, the cytotoxicity tests with L929 cell line revealed that the experimental POC/CNTs nanocomposites possessed good in vitro biocompatibility.