A robust luminescent assay for screening alkyladenine DNA glycosylase inhibitors to overcome DNA repair and temozolomide drug resistance / 药物分析学报

Temozolomide(TMZ)is an anticancer agent used to treat glioblastoma,typically following radiation therapy and/or surgical resection.However,despite its effectiveness,at least 50％of patients do not respond to TMZ,which is associated with repair and/or tolerance of TMZ-induced DNA lesions.Studies have demonstrated that alkyladenine DNA glycosylase(AAG),an enzyme that triggers the base excision repair(BER)pathway by excising TMZ-induced N3-methyladenine(3meA)and N7-methylguanine le-sions,is overexpressed in glioblastoma tissues compared to normal tissues.Therefore,it is essential to develop a rapid and efficient screening method for AAG inhibitors to overcome TMZ resistance in glio-blastomas.Herein,we report a robust time-resolved photoluminescence platform for identifying AAG inhibitors with improved sensitivity compared to conventional steady-state spectroscopic methods.As a proof-of-concept,this assay was used to screen 1440 food and drug administration-approved drugs against AAG,resulting in the repurposing of sunitinib as a potential AAG inhibitor.Sunitinib restored glioblastoma(GBM)cancer cell sensitivity to TMZ,inhibited GBM cell proliferation and stem cell char-acteristics,and induced GBM cell cycle arrest.Overall,this strategy offers a new method for the rapid identification of small-molecule inhibitors of BER enzyme activities that can prevent false negatives due to a fluorescent background.

Apoptosis-promoting effect of temozolomide loaded nanoparticles combined with low intensity focused ultrasound on human glioma cells / 中华超声影像学杂志

Objective:To prepare liquid-gas phase modified nanoparticles (TMZ/PFP/PLGA NPs) of perfluoropentane (PFP) and temozolomide (TMZ) encapsulated by polylactic-glycolic acid copolymer (PLGA), combined with low intensity focused ultrasound (LIFU) irradiation, and to investigate its ultrasound imaging ability and intervention effect on human glioma cells in vitro.Methods:TMZ/PFP/PLGA NPs were prepared by compound emulsion method. The basic physical and chemical properties and drug loading ability of TMZ/PFP/PLGA NPs were detected. CCK-8 assay was used to detect the cytotoxicity of nanoparticles in vitro and the effect of synergistic intervention with LIFU on the survival rate of glioma cells. The expression levels of apoptosis related proteins Bcl-2, Bax and caspase-3 were detected by Western blot.Results:Under transmission electron microscope, TMZ/PFP/PLGA NPs showed a circular core-shell structure with regular morphology, particle size was (137.9±63.31)nm, encapsulation efficiency of TMZ was (83.01±5.57)%, drug loading was (3.19±0.22)%. The survival rate of U251 cells was still above 70% after 24 hours of co-incubation with nanoparticles. Under the synergistic effect of LIFU irradiation, the apoptosis of U251 cells was accelerated and the survival rate of U251 cells was significantly decreased. The results of Western blot showed that the synergic intervention could significantly down-regulate the expression of apoptosis related protein Bcl-2, and significantly up-regulate the expression of Bax protein and caspase-3 protein (all P<0.05). Conclusions:TMZ/PFP/PLGA NPs have good basic physical and chemical properties. TMZ/PFP/PLGA NPs have low cytotoxicity in vitro while efficiently loading chemotherapeutic drug timozolomide. Synergistic intervention under LIFU irradiation can significantly accelerate the apoptosis of U251 glioma cells, which has a good application prospect.

Efficacy of intensity modulated radiotherapy with sequential chemotherapy in the treatment of high-grade glioma and analysis of influential factors / 中国基层医药

Objective:To investigate the efficacy of intensity-modulated radiotherapy with sequential chemotherapy in the treatment of high-grade glioma and analyze the influential factors.Methods:A total of 56 patients with high-grade glioma who received treatment in Yantai Municipal Laiyang Central Hospital from January 2014 to January 2016 were retrospectively analyzed. All patients underwent three-dimensional conformal radiotherapy or enhanced radiotherapy. The use of bevacizumab, pathological grade, and preoperative and postoperative Karnofsky Performance Status scores in all patients were recorded. Cox and other proportional risk regression models were used to analyze the predictors of patient mortality and receiver operating characteristic (ROC) curve analysis was performed.Results:All patients were followed up to April 2022. Follow-up results showed that the median survival time of patients receiving concurrent chemotherapy with temozolomide and adjuvant chemotherapy with temozolomide was 11.6 months. Univariate analysis showed that pathological grade, Karnofsky Performance Status scores, and the degree of tumor resection were correlated with the prognosis of patients ( P = 0.022, 0.049, 0.022). Multivariate analysis showed that the degree of tumor resection and pathological grade were the independent influential factors of prognosis ( P = 0.010, 0.010). Survival curve analysis revealed that the median survival time of patients subjected to total tumor resection was 12.6 months and that of patients subjected to partial tumor resection was 4.8 months. The median survival time of patients subjected to total tumor resection was longer than that of patients subjected to partial tumor resection. The median survival time of patients with WHO grade Ⅲ tumors was 25.2 months, and it was 6.3 months for patients with WHO grade Ⅳ tumors. The median survival time of patients with WHO grade Ⅲ tumors was longer than that of patients with WHO grade Ⅳ tumors. The receiver operating characteristic curve analysis results showed that the area under the receiver operating characteristic curve plotted for using WHO classification of tumors in the neurological system and surgical methods to predict the death of patients with high-grade glioma was 0.783 and 0.814, respectively. WHO tumor grade and surgical methods for prediction of prognosis of high-grade glioma had high accuracy. Conclusion:Low pathological grade and total resection are independent protective factors for the prognosis of patients with high-grade glioma.

Marcadores tumorales CA125, He4 e índice ROMA en cáncer de ovario / Tumor markers CA125, He4, ROME index in ovarian cancer / Marcadores tumorais CA125, He4 e índice ROMA no câncer de ovário

El cáncer de ovario es un problema de salud pública para el cual no se cuenta con métodos de tamizaje estandarizados, no obstante, los marcadores Ca125, He4 y el índice de Roma tiene un gran valor en el diagnóstico y pronóstico de esta patología. Objetivo. Analizar el comportamiento de los marcadores tumorales Ca125 y He4 e índice de Roma en la predicción de malignidad en pacientes con masas ováricas. Materiales y Métodos. Se tomaron los resultados de laboratorio de 112 mujeres atendidas en el Hospital General Ambato de los valores séricos de Ca125, He4 y su correspondiente cálculo del índice de Roma. Se los dividió en el grupo pre y postmenopáusico, maligno y benigno. Resultados. El análisis de los resultados definió la relación de Ca 125 y He4 con el diagnóstico de cáncer de ovario con un nivel de confianza del 95% y valor de p<0,05. La probabilidad de diferenciar cáncer de ovario de procesos benigno para Ca125, He4 e índice de Roma fue del 93,33%, 84,4 y 99,7, respectivamente. Conclusiones. El mejor predictor de malignidad es el índice de Roma. Se encontraron valores séricos elevados de He4 mayores para pacientes postmenopáusicas. Se requieren más estudios que avalen un método de tamizaje estandarizado para el cáncer de ovario.

Ovarian cancer is a public health problem for which there are no standardized screening methods; however, Ca125, He4 and Rome index markers are of great value in the diagnosis and prognosis of this pathology. Objective. To analyze the behavior of tumor markers Ca125 and He4 and Rome index in the prediction of malignancy in patients with ovarian masses. Materials and Methods. The laboratory results of 112 women attended at Hospital General Ambato were taken for serum Ca125, He4 and their corresponding calculation of the Rome index. They were divided into premenopausal and postmenopausal, malignant and benign groups. Results. Analysis of the results defined the relationship of Ca 125 and He4 with the diagnosis of ovarian cancer with a confidence level of 95% and value of p<0.05. The probability of differentiating ovarian cancer from benign processes for Ca125, He4 and Rome index was 93.33%, 84.4 and 99.7, respectively. Conclusions. The best predictor of malignancy is the Rome index. Elevated serum He4 values were found to be higher for postmenopausal patients. Further studies are needed to support a standardized screening method for ovarian cancer.

O câncer do ovário é um problema de saúde pública para o qual não existem métodos de triagem padronizados. No entanto, os marcadores índice Ca125, He4 e Roma são de grande valor no diagnóstico e prognóstico desta patologia. Objetivo. Analisar o comportamento dos marcadores tumorais Ca125 e He4 e o índice de Roma na previsão de malignidade em pacientes com massas ovarianas. Materiais e métodos. Os resultados laboratoriais de 112 mulheres tratadas no Hospital Geral Ambato foram tomados para o soro Ca125, He4 e seu correspondente cálculo do índice de Roma. Eles foram divididos em grupos pré e pós-menopausa, malignos e benignos. Resultados. A análise dos resultados definiu a associação de Ca125 e He4 com o diagnóstico de câncer de ovário a um nível de confiança de 95% e valor de p<0,05. A probabilidade de diferenciar o câncer de ovário dos processos benignos para Ca125, He4 e índice de Roma foi de 93,33%, 84,4 e 99,7, respectivamente. Conclusões. O melhor preditor de malignidade é o índice de Roma. Os valores elevados de soro He4 foram considerados mais altos para pacientes na pós-menopausa. São necessários mais estudos para apoiar um método padronizado de triagem para o câncer de ovário.

Mild overexpression of a novel transcription factor Grainy head like-2 (Grhl2) elicits hybrid phenotype in human astrocytoma cells

The Grainy head like-2 (Grhl2) transcription factor plays a major role in embryonic and cancer development. The role of Grhl2 has been intensively studied in various cancers but not for brain cancer. Hence, in this study, we provide a preliminary understanding on the role of Grhl2 that regulate the transition of astrocytoma cells. The human A172 astrocytoma cell line, a mesenchymal cell characterized by mild overexpression of Grhl2 transcription factor, was used in this study. At first, the Grhl2 stably overexpressing A172 clones into three types i.e., Grhl2+ (mild), Grhl2++ (moderate) and Grhl2+++ (high) based on mRNA and protein expression levels of Grhl2 were characterized. Phenotypic characteristics of vector and Grhl2+ cells were observed using phase contrast microscopy. Quantitative PCR (qPCR), Western blot and immunofluorescence were used to detect the level of mesenchymal markers (N-cadherin/vimentin) and also epithelial markers (E-cadherin/ ?- catenin) in vector and Grhl2+ cells. The migration and invasion characteristics of vector and Grhl2+ cells were determined by scratch assay and Boyden chamber assay. Further, the Grhl2+ cells were characterized to determine the effect of temozolomide chemotherapy drug which were widely used in treating brain cancer. As expected, in phase contrast image, we observed the mesenchymal characteristic of A172 cells becomes hybrid phenotype i.e., mixture of mesenchymal (spindle-like fibroblast morphology) and epithelial (cobblestone like appearance) cells upon Grhl2 mild expression (Grhl2+) when compared to vector cells. Further, we found that there was a significant upregulation of E-cadherin at both mRNA and protein levels in Grhl2+ cells when compared to vector cells. There was a significant upregulation of ?-catenin, N-cadherin and vimentin at mRNA levels, but there was no significant upregulation at the protein levels in Grhl2+ cells compared to the vector cells. The migration and invasion were diminished in Grhl2+ cells when compared to the vector control cells. We observed that the Grhl2+ were sensitive to the temozolomide compared to the vector cells. This infers that the Grhl2+ cells were unable to attain complete transition of mesenchymal to epithelial state, and hence we categorized the Grhl2+ cells as hybrid phenotype. The results provide a better understanding of the largely unknown function of Grhl2 in human astrocytoma cells as tumor progression or suppression.

Clinical efficacy of temozolomide combined with X-ray stereotactic radiotherapy in the treatment of recurrent glioma / 中国医师杂志

Objective:To investigate the curative efficacy of X-ray stereotactic radiotherapy combined with temozolomide in the treatment of recurrent glioma.Methods:48 patients with recurrent glioma treated in Mianyang Central Hospital from January 2018 to January 2019 were retrospectively selected, including 24 patients treated with stereotactic radiotherapy as the control group and 24 patients treated with temozolomide combined with stereotactic radiotherapy as the observation group. The treatment effect, inflammatory factor level, incidence of adverse events and survival rate were compared between the two groups.Results:The complete remission rate and total effective rate in the observation group were significantly higher than those in the control group (66.7% vs 37.5%, 87.5% vs 62.5%) (all P<0.05). There were no significant differences in serum levels of hepatocyte growth factor (HGF), tumor necrosis factor-α (TNF-α) and interleukin-17 (IL-17) between the two groups before treatment (all P>0.05). After treatment, the serum levels of HGF, TNF-α and IL-17 in observation group was significantly lower than those in control group (all P<0.05). The incidence of adverse events in the observation group was significantly lower than that in the control group ( P<0.05). During follow-up of 6, 12 and 18 months, the survival rate of patients in the observation group was significantly higher than that in the control group, with statistically significant difference (all P<0.05). Conclusions:The combination of X-ray stereotactic radiotherapy with temozolomide in the treatment of recurrent glioma shows better clinical outcome and extended survival rate. To conclude, this combined treatment is recommended in further clinical promotion.

Anti-tumor activity and mechanisms of IDO1 inhibitor in combined treatment with temozolomide on human glioma cell lines / 药学学报

We analyzed the anticancer effect and mechanism of the novel indoleamine 2,‍3-dioxygenase 1 (IDO1) inhibitor NLG-919 combined with temozolomide (TMZ) on human glioma cell lines. The anti-tumor activity of NLG-919 and temozolomide after single and combined treatments was detected by MTT assay. Colony formation assay, invasion assay and migration assays were used to detect the effects of NLG-919 and temozolomide alone or in combination on proliferation, invasion and migration of human glioma cells. A flow cytometry assay was used to detect cell apoptosis, cell cycle arrest, reactive oxygen species (ROS) production and mitochondrial membrane potential damage (JC-1). An immunofluorescence assay was used to detect the expression level of IDO1 and HPLC was used to detect the expression level of L-kynurenine (Kyn) to explore the anti-tumor mechanism of NLG-919 and temozolomide. The results show that NLG-919 had a weak in vitro inhibitory effect compared to that of temozolomide. The IC50 of NLG-919 on U251 cells and U87 after 72 h was 26.9 and 30.7 μmol·L-1, respectively. However, when NLG-919 was used in combination with temozolomide, its anti-glioma activity was significantly increased. Compared with the single treatment, the combination treatment had a potent ability to inhibit proliferation, invasion and migration of glioma cells. Combination treatment improved the capacity of temozolomide to induce cell cycle arrest and inhibit the growth of glioma cells. NLG-919 significantly down-regulated the expression and activity of IDO1 in glioma cells, and the inhibitory effect was improved after combination with temozolomide, and effectively blocked the production of Kyn through the metabolism of L-tryptophan (Trp). In conclusion, the IDO1 inhibitor NLG-919 and temozolomide showed synergistic effects in the anticancer therapy of human glioma cell lines.

Inhibition of Ciliogenesis Enhances the Cellular Sensitivity to Temozolomide and Ionizing Radiation in Human Glioblastoma Cells / 生物医学与环境科学（英文）

Objective@#To investigate the function of primary cilia in regulating the cellular response to temozolomide (TMZ) and ionizing radiation (IR) in glioblastoma (GBM).@*Methods@#GBM cells were treated with TMZ or X-ray/carbon ion. The primary cilia were examined by immunostaining with Arl13b and γ-tubulin, and the cellular resistance ability was measured by cell viability assay or survival fraction assay. Combining with cilia ablation by IFT88 depletion or chloral hydrate and induction by lithium chloride, the autophagy was measured by acridine orange staining assay. The DNA damage repair ability was estimated by the kinetic curve of γH2AX foci, and the DNA-dependent protein kinase (DNA-PK) activation was detected by immunostaining assay.@*Results@#Primary cilia were frequently preserved in GBM, and the induction of ciliogenesis decreased cell proliferation. TMZ and IR promoted ciliogenesis in dose- and time-dependent manners, and the suppression of ciliogenesis significantly enhanced the cellular sensitivity to TMZ and IR. The inhibition of ciliogenesis elevated the lethal effects of TMZ and IR via the impairment of autophagy and DNA damage repair. The interference of ciliogenesis reduced DNA-PK activation, and the knockdown of DNA-PK led to cilium formation and elongation.@*Conclusion@#Primary cilia play a vital role in regulating the cellular sensitivity to TMZ and IR in GBM cells through mediating autophagy and DNA damage repair.

Plumbagin Enhanced Inhibitory Effect of Temozolomide on Migration and Invasion of Human Glioma U251 Cells Through E-cadherin / 肿瘤防治研究

Objective To investigate the inhibitory effect and mechanism of temozolomide on migration and invasion of U251 human glioma cells enhanced by plumbagin. Methods CCK-8 method was used to study the effects of plumbagin, temozolomide and plumbagin+temozolomide on the proliferation of glioma U251 cells. Cell scratch test was used to detect the migration of U251 cells in the control (DMSO), plumbagin, temozolomide and plumbagin+temozolomide groups for 48h. Transwell assay was used to detect the effect of the combination therapy on the invasion of U251 cells. Western blot was used to detect the relative expression levels of E-cadherin in three groups. Results CCK-8 showed that the proliferation inhibition rate of U251 cells treated with plumbagin (1.25 μmol/L) combined with temozolomide (200 μmol/L) for 48h was 75.69%, significantly higher than that treated with plumbagin alone (P=0.012) or temozolomide alone (P=0.034). Cell scratch assay showed that the combination of plumbagin and temozolomide could significantly enhance the inhibition effect of temozolomide on the migration of U251 cells (P=0.023). Transwell assay showed that the invasion ability of U251 cells was significantly decreased after the combination therapy (P < 0.05). The protein expression of E-cadherin in the combination group was significantly higher than those in plumbagin or temozolomide groups (P < 0.05). Conclusion Plumbagin combined with temozolomide can inhibit the migration and invasion of glioma cells and enhance the sensitivity of glioma cells to temozolomide. And the effect is achieved by the protein expression of E-cadherin.

Preliminary exploration of relevant mechanisms and effects of LncRNA LY6E-DT on temozolomide resistance in high grade glioma cell U251 / 中华内分泌外科杂志

Objective:To investigate the effect of long non-coding RNA (LncRNA) LY6E-DT on temozolomide (TMZ) resistance in high grade glioma cells (HGG) cells and its mechanism.Methods:Bioinformatics screened the LncRNA correlated to the expression of O6-methylguanine-DNA methyltransferase (MGMT) in HGG tissue, and excavated potentially related microRNA (miRNA) . HGG cell U251 was cultured and randomly divided into control group, resistance group and interference group. Resistance group and interference group were treated with 0.2-16.0 μg·ml -1 TMZ gradient incremental induction, and isosmotic PBS was used to treat control group cells. Control group and resistance group were transfected with control vector, while the interference group was transfected with shRNA interference vector targeting LY6E-DT by lentivirus. The semi-inhibitory concentration (IC 50) of TMZ in each group was detected by CCK-8 experiment, the expression levels of LY6E-DT, miR-125a-5p and MGMT mRNA in each group were detected by real-time fluorescent quantitative PCR (RT-qPCR) , and the expression levels of MGMT protein were detected by Western blot. The effect of miR-125a-5p on MGMT and LY6E-DT was detected by luciferase reporter gene method. Results:LY6E-DT expression was positively correlated with MGMT (Pearson correlation coefficient = 0.32, P<0.001) , and it was found that LY6E-DT expression was significantly lower in HGG tissues, but it was not conducive to the prognosis of HGG patients; In the control group, resistance group and interference group, the expressions of LY6E-DT were 1.000±0.047, 3.704±0.402 and 0.743±0.064; the expressions of miR-125a-5p were 1.000±0.049, 0.351±0.031 and 0.934±0.050; the expressions of MGMT mRNA were 1.000±0.017, 5.205±0.462 and 3.183±0.667; the expressions of MGMT protein are 0.108±0.012, 0.891±0.063 and 0.375±0.038; TMZ IC 50 are 6.79±0.71, 30.52±3.69 and 15.64±2.25 μg·ml -1. Compared with the control group, LY6E-DT, MGMT and TMZ IC50 in the resistance group were significantly higher, while LY6E-DT expression in the interference group was significantly lower, MGMT and TMZ IC 50 were significantly higher ( P<0.05) ; Compared with the resistance group, the expression of LY6E-DT, MGMT mRNA and protein and TMZ IC 50 decreased significantly in the interference group ( P<0.05) . miR-125a-5p significantly inhibited luciferase expression of MGMT 3'UTR ( P<0.01) , while LY6E-DT significantly restored the expression level ( P<0.01) . Conclusion:LY6E-DT can promote MGMT expression and TMZ resistance in HGG cells, which is related to the inhibition of miR-125a-5p expression.

Establishment of a mouse model bearing orthotopic temozolomide-resistant glioma / 南方医科大学学报

OBJECTIVE@#To establish a mouse model bearing orthotopic temozolomide (TMZ)-resistant glioma that mimics the development of drug resistance in gliomas @*METHODS@#Seventy-eight adult C57BL/6 mice were randomly divided into 6 groups (@*RESULTS@#The mouse models bearing TMZresistant glioma was successfully established. The cells from the high-dose induced group showed a significantly higher colony-forming rate than those from the high-dose control group (@*CONCLUSIONS@#Progressive increase of TMZ doses in mice bearing orthotopic gliomas can effectively induce TMZ resistance of the gliomas.

Downregulation of hsa_circ_0000936 sensitizes resistant glioma cells to temozolomide by sponging miR-1294

Glioma is one of the most aggressive forms of brain tumor and is hallmarked by high rate of mortality,metastasis and drug resistance. Herein, we explore the role of circular RNA (circRNA) hsa_circ_0000936 inthe resistance of glioma cells to temozolomide (TMZ). In this study, Relative changes in gene expression levelswere compared using qRT-PCR. The role of hsa_circ_0000936 was characterized by cell count kit -8 assay andflow cytometry. Luciferase reporter assay was carried out for target validation.We found that hsa_circ_0000936was upregulated in glioma tissues as compared to their adjacent normal tissues. Increased expression ofhsa_circ_0000936 was found in the glioma tissues of patients showing resistance to TMZ compared with thatof patients showing sensitivity to TMZ. The upregulation of hsa_circ_0000936 was also confirmed in TMZresistant glioma cells. miR-1294 was downregulated in TMZ-resistant glioma cells and identified as a directtarget of hsa_circ_0000936. Downregulation of hsa_circ_0000936 increased the sensitivity of TMZ-resistantglioma cells towards TMZ. Moreover, restoration of miR-1294 could abrogate the promoting effect ofhsa_circ_0000936 on TMZ resistance in TMZ-resistant glioma cells. In conclusion, downregulation ofhsa_circ_0000936 sensitizes TMZ-resistant glioma cells to TMZ by sponging miR-1294, suggesting thathsa_circ_0000936 may be a potential target for overcoming the resistance of glioma cells to TMZ.

Transcatheter arterial infusion of anti-programmed cell death 1 antibody pembrolizumab combined with temozolomide or nab-paclitaxel in patient with primary anorectal malignant melanoma: Four case reports

Primary anorectal malignant melanoma (ARMM) is an extremely rare but aggressive tumor. We assessed the efficacy and safety of transcatheter arterial infusion (TAI) with anti-PD-1 antibody pembrolizumab at a dosage of 100 mg with 0.9% NaCl at a volume of 100 mL administered over a 30-min period every 3 weeks, combined with temozolomide or albumin-bound paclitaxel (nab-paclitaxel) in four patients with ARMM. Temozolomide was administered orally once per day at a dosage of 200 mg/m2/d for five consecutive days about every 4 weeks. Nab-paclitaxel was administered at a dosage of 200mg/m2/d once about every 3 weeks. Among four patients with a median follow-up of 8.9 months, two cases showed Murine Double Minute 2 (MDM2) amplification. Case 1 with Stage II ARMM showed pathological complete response after four cycles of TAI with pembrolizumab combined with nab-paclitaxel. Case 4 was at Stage II and showed stable disease consistently throughout the treatment. Case 2 was at stage II and Case 3 was at stage III, and they showed partial response after four or three cycles, respectively, of TAI with pembrolizumab combined with temozolomide. No Grades 3–4 adverse reactions were observed. Therefore, a combination of TAI with pembrolizumab and temozolomide or with nab-paclitaxel appears to be a promising option for treating ARMM. However, multicenter clinical trials are required to confirm the efficacy and safety of this procedure

Targeting of temozolomide using magnetic nanobeads: an in vitro study

Temozolomide, a chemotherapeutic drug that is often administered for the treatment of brain cancer has severe side effects and a poor aqueous solubility. In order to decrease the detrimental effect of the drug over healthy cells, a novel drug delivery vehicle was developed where the therapeutic drug was encapsulated within the hydrophobic cavities of b-CD modified magnetite nanoparticles, which are embedded in chitosan nanobeads prepared by salt addition. In-vitro studies have shown that the magnetic properties of the novel delivery vehicle are adequate for targeted drug delivery applications under an external magnetic field. Additionally, an increase in the amount of chitosan was shown to exhibit a strong shielding effect over the magnetic properties of the delivery vehicle, which lead to deterioration of the amount of captured drug at the targeted area, suggesting a delicate balance between the amounts of constituents composing the drug delivery vehicle.

Gambogic acid enhances sensitivity of glioma U251 cells to temozolomide by inhibiting GLUT-3/ AKT signaling pathway / 中国肿瘤生物治疗杂志

@#[Abstract] Objective: To explore whether gambogic acid can enhance the sensitivity of glioma U251 cells to temozolomide and further explore its mechanism. Methods: U251 cells were cultured in vitro and divided into blank control group, gambogic acid treatment group, temozolomide alone treatment group and combined treatment group. The cells survival rates of cells in each group was detected by CCK-8 assay. Flow cytometry was used to detect cell apoptosis and changes in ROS level. Western blotting was used to detect the changes in protein expressions. Results: CCK-8 results showed that the cells survival rates of the four groups after treatment for 24 h were (98.65±3.68)%, (93.58±2.47)%, (66.81±2.39)% and (38.65±4.13)%, respectively. It can be seen that the combined treatment could significantly increase the inhibitory effect of temozolomide on U251 cells. The proportion of apoptotic U251 cells in the combined treatment group was (61.43±2.58)%, which was significantly higher than that of (26.68±1.82)% in the temozolomide-treated group. Combined treatment of gambogic acid and temozolomide could up-regulate ROS level in U251 cells, reduce the expressions of GLUT-3 and p-AKT, and inhibit the GLUT-3/AKT signaling pathway. Conclusion: Gambogic acid combined with temozolomide can enhance the sensitivity of U251 cells to temozolomide by up-regulating ROS level and inhibiting GLUT-3/AKT signaling pathway in U251 cells, and provides a theoretical basis for the application of gambogic acid in the treatment of glioma.

Effects and mechanism of Ligusticum chuanxiong volatile oil in combination with temozolomide in treatment of glioma by regulating P-gp protein / 中草药

Objective: To investigate the anti-tumor effect of Ligusticum chuanxiong volatile oil in combination with temozolomide (TMZ) in the treatment of glioma, and illuminate its possible mechanism. Methods: After C6 glioma animal model was successfully finished, changes of body weight, survival status, tumor volume, and the tumor inhibition rate of rats were detected in the TMZ group and the compatibility group of the volatile oil of L. chuanxiong and TMZ. The concentration of TMZ in the internal and external fluids of U87-MG cells was measured by HPLC after the administration of TMZ and the combination of volatile oil of L. chuanxiong and TMZ, and the differences of the content were analyzed statistically. Western blotting was used to study the effects of TMZ monotherapy, L. chuanxiong volatile oil and TMZ on the expression of P-gp protein of U87-MG cells.Results: Compared with TMZ group, the tumor volume of rats in the compatibility group was significantly decreased (P < 0.05), which was positively correlated with the amount of volatile oil. At the same time, the weight gain of the rats in the compatibility group was increased and the survival status was better. Volatile oil of L. chuanxiong can promote the entry of TMZ into U87-MG cells, and with the increase concentration of volatile oil, the promoting effect was stronger. Volatile oil at 6.25 × 10-3 μL/mL can significantly increase the accumulation of TMZ in the internal fluid (P < 0.05). Western blotting analysis showed that P-gp expressions of cells treated with combination treatment with TMZ (20 μg/mL) and volatile oil [(3.125 × 10-3), (6.25 × 10-3) μL/mL] were markedly down-regulated (P < 0.01), when compared with TMZ group. Conclusion: The volatile oil of L. chuanxiong can promote TMZ entry into glioma cells and then enhance TMZ-induced anticancer efficiency in vivo by inhibiting P-gp expression.

Over-expression of programmed cell death 5 gene enhances chemosensitivity of brain glioma cells to temozolomide / 中国肿瘤生物治疗杂志

@# Objective: To explore the role of tumor suppressor gene programmed cell death 5 gene (PDCD5) in the growth and temozolomide (TMZ) sensitivity of brain glioma cells. Methods:Atotal of 116 patients with cerebral glioma admitted to the Department of Neurosurgery, First Clinical Hospital of Jilin University from January 2009 to December 2014 were enrolled in this study. QPCR, WB and immunohistochemistry method were used to detect the mRNAand protein expressions of PDCD5 in glioma cell lines (U87, U251), U87 cell line with stable PDCD5 expression (U87-PDCD5), glioma cells with si-PDCD5 transfection and primary cerebral glioma tissues, respectively. MTT assay was used to detect the effect of over-expression or knockdown of PDCD5 on the growth and TMZ-sensitivity of glioma cells. The subcutaneous tumor-bearing model of glioma cell line U87 was established in nude mice, and then the experimental mice were randomly divided into control group, TMZ group, PDCD5 group and TMZ+exogenous PDCD5 recombinant expression vector group.After 20 days, the animals were sacrificed by cervical dislocation and the tumor tissue was excised to measure the tumor volume and weigh. The expression of PDCD5 in tumor tissues was detected by qPCR and WB methods, and the effects of PDCD5 combined with TMZ on the growth of gliomas were also analyzed. Results: The relative mRNA and protein expressions of PDCD5 in U87 cells were significantly lower than those in U251 cells (both P<0.05), and the mRNA and protein expressions of PDCD5 in high level glioma tissues were significantly lower than those in low level tissues (all P<0.05). The sensitivity of U87-PDCD5 cells and U251 cells to TMZ was higher than that of U87 cells (all P<0.05). The sensitivity of cells to TMZ in U87-PDCD5-siRNA group and U251siRNA group was significantly lower than that of the control group (both P<0.05). The tumor volume and weigh to fnudemicexenografts were compared,and the results showed control group>TMZ group>PDCD 5group>combined group(allP<0.05);however, the mRNA and protein expressions of PDCD5 in the transplanted tumor tissues of each group showed the opposite trend (all P<0.05). Conclusion: PDCD5 over-expression can enhance the chemosensitivity of braingliomato the chemotherapy drug TMZ, while silencing of PDCD5 expression exertsthe opposite effect.The combination of PDCD5 and TMZ can better inhibit the growth of xenografts in nude mice.

lncRNA POU3F3 affects temozolomide-resistance in high-grade glioma cells via regulating MGMT expression / 中国肿瘤生物治疗杂志

@# Objective: To explore the mechanism of long non-coding RNA POU3F3 (lncRNAPOU3F3) affecting temozolomide (TMZ)-resistance in high-grade glioma cells via regulating MGMT expression. Methods: Sixty cases of tissues from patients treated at the Department of Neurosurgery, Peking University International Hospital during January 2016 and January 2018 were collected for this study, including 12 cases from brain trauma patients (normal group), 30 cases from primary high-grade glioma patients (primary onset group) and 18 cases from recurrent high-grade glioma patients (recurrence group, accepted surgery+TMZ already). U251 cells were induced with TMZ at the concentration of 1, 2, 4 and 8 μg/ml and maintained normal growth for a week to construct TMZ-resistant U251cell line (U251 TMZ-resistance, U251-TR); and the normal control group was treated with equal volume of physiological saline. Reverse transcription polymerase chain reaction (qPCR) and Wb were used to detect the mRNA and protein expressions of POU3F3 and MGMT (methylguanine DNA methyltransferase) in normal brain tissues and glioma cells. Lentivirus transfection was used to construct U251 cell line with stable POU3F3 interference (U251-TR siPOU3F3); CCK-8 was used to detect TMZ IC50 value (the half maximal inhibitory concentration) in each group of U251 cells, and Wb was used to detect the expression of MGMT protein in each group of cells. Results: Compared with the normal group and primaryonset group, the expression of POU3F3 in recurrence group was significantly increased (P<0.01). The TMZ IC50 of U251-TR cells was significantly higher than that of U251 cells (P<0.01), and The TMZ IC50 of U251-TR siPOU3F3 cells was significantly lower than that of U251-TR cellsbut higher than that of U251 cells (all P<0.01). The protein and mRNA expressions of POU3F3 and MGMT in U251-TR cells were significantly higher than that in U251 cells (P<0.01), while those expressions in U251-TR siPOU3F3 cells were significantly lower than those in U251-TR cells (P<0.01).Conclusion: lncRNAPOU3F3 is the key factor to promote TMZ resistance in human high-grade gliomas cells, which may exert certain guiding significance in the clinical treatment for TMZ resistance.

Curative effect observation of erlotinib plus temozolomide for recurrence/progression in patients with EGFR gene mutation in NSCLC with brain metastases after whole brain radiotherapy / 国际肿瘤学杂志

Objective To observe the clinical efficacy and safety of erlotinib plus temozolomide for recurrence/progression patients with epidermal growth factor receptor (EGFR) gene mutation in non-small cell lung cancer (NSCLC) with brain metastases after whole brain radiotherapy.Methods A total of 68 EGFR gene mutation NSCLC patients with brain metastases of intracranial recurrence/progression after whole brain radiotherapy were selected from August 2013 to June 2018 in Baoji Central Hospital of Shaanxi Province and Xintai People's Hospital of Shandong Province.All the patients were randomly divided into erlotinib group and combined treatment group (erlotinib combined with temozolomide) using random number table method.The patients in erlotinib group (34 cases) were treated with oral erlotinib 150 mg/d until progression or unacceptable adverse reaction,and the patients in combined treatment group (34 cases) were given erlotinib and oral temozolomide 150 mg/(m2 · d) for 1-5 day,every 28 days was a cycle,temozolamide for 6 cycles.Comparison was made on curative effects and occurrence condition of adverse reactions between the two groups.Results The overall response rates in the erlotinib group and combined treatment group were 11.8％ (4/34)and 32.4％ (11/34) respectively,and the disease control rates in the two groups were 35.3％ (12/34) and 64.7％ (22/34) respectively,with significant differences (x2 =4.191,P =0.041;x2 =5.882,P =0.015).The median progression-free survival in the erlotinib group and combined treatment group were 3.22 months and 5.29 months respectively,and the median overall survival in the two groups were 5.60 months and 7.90 months respectively,with significant differences (x2 =9.269,P =0.002;x2 =11.005,P =0.001).The incidence of nausea and vomiting in combined treatment group was significantly higher than that in erlotinib group [67.6％ (23/34) vs.14.7％ (5/34)],with a significant difference (x2 =19.671,P ＜ 0.001),but there were no significant differences in the incidences of other adverse reactions (all P ＞ 0.05).The patients in the two groups had no more than grade Ⅲ of adverse reactions.Conclusion The curative effect of erlotinib combined with temozolomide is better in the treatment of recurrence/progression patients with EGFR gene mutation in NSCLC with brain metastases after whole brain radiotherapy,with mild adverse reactions and good patients' tolerance.

Meta-analysis of efficiency and safety of WBRT±temozolomide in treatment of brain metastases from NSCLC / 中华放射肿瘤学杂志

Objective To compare the efficacy and safety between whole brain radiotherapy (WBRT) and WBRT combined with temozolomide (TMZ) in the treatment of non-small cell lung cancer with brain metastases.Methods According to the retrieval strategy,the Chinese and English literatures before February 2018 were retrieved from EMbase,Cochrane,PubMed,Wanfang database,Chongqing VIP and CNKI,The target literatures were selected according to the inclusion and exclusion criteria,The quality of the included studies and extracted data was independently assessed by 3 researchers,The RevMan 5,3 and STATA 12,0 software was used for statistical analysis,The objective remission rate (ORR),the total survival period (OS),the progression-free survival (PFS),and the side effects of chemotherapy were evaluated.Results In total,17 trials consisting of 1128 patients were included,The results of Meta-analysis demonstrated that compared with the WBRT group,the ORR was significantly higher (OR=2.54;95％CI:1.93-3.36;P＜0.001),the PFS was significantly longer (MS R=1.329;95％CI:1.143-1.545;P＜0,001),and the incidence of hematological toxicity (OR=3.44;95％CI:1.63-7.26;P＜ 0.05) and the gastric intestinal reaction (OR=1.69;95％CI:1.24-2.31;P＜0.05) was significantly higher in the WBRT+TMZ group,The heterogeneities were within the acceptable range with statistical significance,The results of OS were invalid due to relatively large heterogeneity,The incidence of headache did not significantly differ between two groups (OR=1.05;95％CI:0.72-1.55;P=0,79).Conclusions Compared with WBRT alone,WBRT combined with TMZ is beneficial to improve the short-term efficacy,whereas the incidence of hematological toxicity and gastrointestinal reaction is higher,The occurrence of headache does not significantly differ between two groups,The benefit of long-term survival remains uncertain.