Mechanism of RIP2 enhancing stemness of glioma cells induces temozolomide resistance.

AIMS: We aimed to investigate the role of receptor-interacting protein 2 (RIP2) in regulation of stemness of glioma cells and chemotherapy resistance. METHODS: Plasmid transfection was used to overexpress RIP2. Chemical inhibitors were used to inhibit RIP2 or NF-κB activity. Cancer stemness of glioma cells was investigated by sphere formation assays, clone formation assays, and xenograft tumor formation assays. The expression of RIP2, p-NF-κB, IκBα, CD133, or SOX-2 was detected by Western blotting and immunofluorescence. Apoptosis was detected by flow cytometry. Immunohistochemical staining was used to detect the expression of RIP2, CD133, and SOX-2 in xenograft tumor tissue. The effect of the RIP2/NF-κB pathway on temozolomide (TMZ) resistance was evaluated by xenograft tumor assay. RESULTS: Transfection with RIP2 plasmid enhanced the sphere formation capability of U251 cells, clone formation capability, and xenograft tumor formation capability. RIP2 could mediate TMZ resistance by upregulating the expression of CD133 and SOX-2 by activating the NF-κB pathway. Both RIP2 inhibitor GSK583 and the NF-κB inhibitor SC75741 could reverse the resistance of U251 cells to TMZ. CONCLUSION: RIP2 mediates TMZ resistance by regulating the maintenance of stemness in glioma cells through NF-κB. Interventions targeting the RIP2/NF-κB pathway may be a new strategy for TMZ-resistant gliomas.

Regulation of temozolomide resistance in glioma cells via the RIP2/NF-κB/MGMT pathway.

BACKGROUND: Temozolomide (TMZ) is a first-line chemotherapy drug for the treatment of malignant glioma and resistance to it poses a major challenge. Receptor-interacting protein 2 (RIP2) is associated with the malignant character of cancer cells. However, it remains unclear whether RIP2 is involved in TMZ resistance in glioma. METHODS: RIP2 expression was inhibited in TMZ-resistant glioma cells and normal glioma cells by using small interfering RNA (siRNA) against RIP2. Plasmid transfection method was used to overexpress RIP2. Cell counting kit-8 assays were performed to evaluate cell viability. Western blotting or immunofluorescence was performed to determine RIP2, NF-κB, and MGMT expression in cells. Flow cytometry was used to investigate cell apoptosis. TMZ-resistant glioma xenograft models were established to evaluate the role of the RIP2/NF-κB/MGMT signaling pathway in drug resistance. RESULTS: We observed that RIP2 expression was upregulated in TMZ-resistant glioma cells, whereas silencing of RIP2 expression enhanced cellular sensitivity to TMZ. Similarly, upon the induction of RIP2 overexpression, glioma cells developed resistance to TMZ. The molecular mechanism underlying the process indicated that RIP2 can activate the NF-κB signaling pathway and upregulate the expression of O6-methylguanine-DNA methyltransferase (MGMT), following which the glioma cells develop drug resistance. In the TMZ-resistant glioma xenograft model, treatment with JSH-23 (an NF-κB inhibitor) and lomeguatrib (an MGMT inhibitor) could enhance the sensitivity of the transplanted tumor to TMZ. CONCLUSION: We report that the RIP2/NF-κB/MGMT signaling pathway is involved in the regulation of TMZ resistance. Interference with NF-κB or MGMT activity could constitute a novel strategy for the treatment of RIP2-positive TMZ-resistant glioma.

Long noncoding RNA OIP5-AS1 targets Wnt-7b to affect glioma progression via modulation of miR-410.

The present study was undertaken to investigate the underlying mechanisms of long noncoding RNA OIP5-AS1 via regulating miR-410 to modulate Wnt-7b in the progression of glioma. To address this problem, we measured the expression of OIP5-AS1 and miR-410 in glioma tissues by qRT-PCR. Glioma U87 cells were transfected with OIP5-AS1 siRNA or miR-410 inhibitors. The targeting relationships among miR-410, OIP5-AS1 and Wnt-7b were verified by luciferase reporter assays. Western blotting was employed to determine the expression of Wnt-7b/ß-catenin pathway-related proteins, while MTT, flow cytometry, Transwell assays and wound-healing assays were used to measure the biological characteristics of glioma cells. The results showed that OIP5-AS1 expression was higher and miR-410 was lower in glioma tissues. Luciferase reporter assays confirmed a targeting relationship between OIP5-AS1 and miR-410, as well as between miR-410 and Wnt-7b. Silencing OIP5-AS1 reduced cell proliferation, invasion and migration of glioma U87 cells and led to depressed expression levels of miR-410, Wnt-7b, p-ß-catenin, GSK-3ß-pS9, c-Myc and cyclin D1. Furthermore, down-regulation of OIP5-AS1 induced G0/G1 phase cell cycle arrest and apoptosis of glioma cells. Inhibitors of miR-410 abolished the biological effects of OIP5-AS1 siRNA in glioma cells. In vivo, OIP5-AS1 knockdown also inhibited tumor growth. Taken together, this research suggested that silencing OIP5-AS1 may specifically block the Wnt-7b/ß-catenin pathway via targeted up-regulating miR-410, thereby inhibiting growth, invasion and migration while promoting apoptosis in glioma cells.

Exosomal miR-214-5p Released from Glioblastoma Cells Modulates Inflammatory Response of Microglia after Lipopolysaccharide Stimulation through Targeting CXCR5.

BACKGROUND AND OBJECTIVE: Exosomes communicate inter-cellularly and miRNAs play critical roles in this scenario. MiR-214-5p was implicated in multiple tumors with diverse functions uncovered. However, whether miR-214-5p is mechanistically involved in glioblastoma, especially via exosomal pathway, is still elusive. Here we sought to comprehensively address the critical role of exosomal miR-214-5p in glioblastoma (GBM) microenvironment. METHODS: The relative expression of miR-214-5p was determined by real-time PCR. Cell viability and migration were measured by MTT and transwell chamber assays, respectively. The secretory cytokines were measured with ELISA kits. The regulatory effect of miR-214-5p on CXCR5 expression was interrogated by luciferase reporter assay. Protein level was analyzed by Western blot. RESULTS: We demonstrated that miR-214-5p was aberrantly overexpressed in GBM and associated with poorer clinical prognosis. High level of miR-214-5p significantly contributed to cell proliferation and migration. GBM-derived exosomal miR-214-5p promoted inflammatory response in primary microglia upon lipopolysaccharide challenge. We further identified CXCR5 as the direct target of miR-214- 5p in this setting. CONCLUSION: Overexpression of miR-214-5p in GBM modulated the inflammatory response in microglia via exosomal transfer.

Delayed cognitive deficits can be alleviated by calcium antagonist nimodipine by downregulation of apoptosis following whole brain radiotherapy.

Radiation therapy is important for the comprehensive treatment of intracranial tumors. However, the molecular mechanisms underlying the pathogenesis of delayed cognitive dysfunction are not well-defined and effective treatments or prevention measures remain insufficient. In the present study, 60 adult male Wistar rats were randomly divided into three groups, which included a control, whole brain radiotherapy (WBRT) (single dose of 30 Gy of WBRT) and nimodipine (single dose of 30 Gy of WBRT followed by nimodipine injection intraperitoneally) groups. The rats were sacrificed 7 days or 3 months following irradiation. At 3 months, the Morris water maze test was used to assess spatial learning and memory function in rats. The results demonstrated that the WBRT group demonstrated a significantly impaired cognitive performance, decreased numbers of hippocampal Cornu Ammonis (CA)1 neurons and upregulated expression of caspase-3 in the dentate gyrus compared with those in the control and nimodipine groups. Reverse transcription-quantitative polymerase chain reaction analysis demonstrated that the WBRT group exhibited increased ratio of B-cell lymphoma 2 (Bcl-2)-associated X protein (Bax)/Bcl-2 compared with that in control and nimodipine groups on day 7 following irradiation. However, the WBRT group exhibited decreased levels of brain-derived neurotrophic factor (BDNF) compared with that in control and nimodipine groups at 3 months following brain irradiation. The levels of growth-associated protein 43 and amyloid precursor protein between the nimodipine group and WBRT group were not statistically significant. The present study demonstrated that neuron apoptosis may lead to delayed cognitive deficits in the hippocampus, in response to radiotherapy. The cognitive impairment may be alleviated in response to a calcium antagonist nimodipine. The molecular mechanisms involved in nimodipine-mediated protection against cognitive decline may involve the regulation of Bax/Bcl-2 and BDNF in the hippocampus.

Downregulation of ZMYND11 induced by miR-196a-5p promotes the progression and growth of GBM.

ZMYND11 (zinc finger MYND-type containing 11) has been widely regarded to be involved in a variety of cancers as a potential suppressor. However, the biological role and mechanism of ZMYND11 in glioblastoma multiform (GBM) remain unknown. In this study, we found that ZMYND11 expression was remarkably decreased in GBM tissues from 20 cases and cell line (U87) compared to normal brain tissue from 10 cases (P < 0.001). Furthermore, we explored that ZMYND11 upregulation significantly suppressed U87 cells proliferation and invasion, induced cell cycle arrest and apoptosis in vitro. Subsequently, we identified increased ZMYND11 inhibited the tumor growth using tumor cells xenograft experiment on rude mice. Moreover, we explored that ZMYND11 was a new direct and functional target of miR-196a-5p in U87 via luciferase reporter assay. In addition, we confirmed the negative correlation between miR-196a-5p and ZMYND11 in GBM tissue and U87 cells by changing the expression level of miR-196a-5p with lentivirus and plasmid vector. Furthermore, we demonstrated that decreased ZMYND11 could reverse suppressive effect of downregulated miR-196a-5p on U87 by rescue experiment. Taken together, ZMYND11 was demonstrated to be a potential and extremely promising suppressor of GBM, while miRNA-196a-5p was quite an important target of treatment of GBM.

miR-133a Promotes TRAIL Resistance in Glioblastoma via Suppressing Death Receptor 5 and Activating NF-κB Signaling.

Recombinant tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL), as a novel cancer therapeutic, is being tested in phase II and III clinical trials; however, TRAIL resistance remains a big obstacle preventing its clinical application. Considering that TRAIL-induced apoptosis through death receptors DR4 and DR5, their activation may be an alternative pathway to suppress TRAIL resistance. In this study, a negative correlation between DR5 expression and TRAIL resistance was observed, and miR-133a was predicted to be the most promising candidate to suppress DR5 expression. Further investigation demonstrated that miR-133a knockdown dramatically suppressed TRAIL resistance in glioblastoma in vitro and in vivo. An NF-κB family member, phosphorylated IκBα (P-IκBα), was shown to be stimulated by miR-133a, leading to the activation of this signaling. Finally, miR-133a was found to be inversely correlated with DR5 expression in human clinical specimens. In conclusion, our data demonstrate that miR-133a promotes TRAIL resistance in glioblastoma by suppressing DR5 expression and activating NF-κB signaling.

Exosomal miR-221 targets DNM3 to induce tumor progression and temozolomide resistance in glioma.

MicroRNA is an important regulator of glioblastoma. This study aims at validating microRNA-221 (miR-221) as a biomarker for glioblastoma, and understanding how miR-221 regulates glioblastoma progression. Using clinical samples, miR-221 expression was analyzed by quantitative reverse-transcriptase PCR (qPCR). SHG-44 cells were treated with anti-miR-221 or U87MG-derived exosomes followed by monitoring changes in cell viability, migration and temozolomide (TMZ) resistance. Bioinformatics approach was used to identify targets of miR-221. The interaction between miR-221 and its target, DNM3 gene, was studied with dual-luciferase reporter assay, Spearman's correlation analysis, and western blotting. To verify that RELA regulates miR-221 expression, RELA-expressing vector or shRNA was introduced into SHG-44 cells and its effect on miR-221 expression was monitored. Both tissue-level and exosomal miR-221 expression increased with glioma grades. In SHG-44 cells, downregulating miR-221 expression inhibited cell proliferation, migration, and TMZ resistance, whereas incubation with U87MG-derived exosomes exerted tumor-promoting effects. DNM3 gene is a target of miR-221. RELA induced miR-221 expression. In glioma, elevated miR-221 expression is a biomarker for glioma. DNM3 is a target of miR-221 and RELA regulates miR-221 expression. The RELA/miR-221 axis is a target for glioma diagnosis and therapy.

DNM3, p65 and p53 from exosomes represent potential clinical diagnosis markers for glioblastoma multiforme.

BACKGROUND: Glioblastoma multiforme (GBM) is the most aggressive and deadly primary brain cancer that arises from astrocytes and classified as grade IV. Recently, exosomes have been reported as an essential mediator in diverse cancer carcinogenesis and metastasis. However, their role in GBM is still unclear. In this study, we aimed to investigate whether blood exosomes can be potential clinical diagnostic markers for GBM. METHODS: We used a xenograft orthotopic mouse model to detect the differentially expressed genes in the brain and blood exosomes of original/recurrent GBM. RESULTS: We found that recurrent GBM had stronger growth capacity and lethality than original GBM in the mouse model. A gene microarray of original tumors and blood exosomes from GBM orthotopic xenografts results showed that DNM3, p65 and CD117 expressions increased, whereas PTEN and p53 expressions decreased in both original tumors and blood exosomes. In the recurrent GBM tumor model, DNM3 and p65 showed increased expressions, whereas ST14 and p53 showed decreased expressions in tumor and blood exosomes of the recurrent GBM mouse model. CONCLUSION: In summary, we found that DNM3, p65 and p53 had a similar trend in brain and blood exosomes both for original and recurrent GBM, and could serve as potential clinical diagnostic markers for GBM.

Downregulation of miR-95-3p inhibits proliferation, and invasion promoting apoptosis of glioma cells by targeting CELF2.

Gliomas are the most common and aggressive types of tumors in human brain, of which the prognosis remains dismal because of their biological behavior. The involvement of miRNAs in tumorigenesis of various kinds of cancers drives us to explore new miRNAs related to gliomas. We measured expression level of miR­95­3p by qRT-PCR in human glioma and non-neoplasm brain tissues and found that higher level of miR­95­3p in glioma tissues of higher grade. Biological functions of miR­95­3p on glioma cells were investigated by MTT assay, flow cytometry and transwell assay. We discovered the cell lines transfected with miR­95­3p ASO (antisense oligonucleotide) had retarded proliferation and invasion but enhanced apoptosis ability. We searched on-line tool Targetscan and selected CELF (CUGBP- and ETR-3-like family 2) as a putative target. Luciferase reporter was employed to confirm the binding sites in 3'UTR region of CELF2 for miR­95­3p. The correlation between expression of CELF2 and miR­95­3p was determined by western blotting and qRT-PCR both in cell lines and human samples. Results showed CELF2 was a direct target of miR­95­3p and expression levels of CELF2 and miR­95­3p were negatively correlated. Finally, CELF2 largely abrogated the effects of miR­95­3p on proliferation, invasion and apoptosis of glioma cells in rescue experiments, which verified the role of CELF2 in miR­95­3p regulating glioma biological behavior. In conclusion, our data suggest the expression level of miR­95­3p is positively related to glioma grade and downregulation of miR­95­3p affects proliferation, invasion and apoptosis of glioma cells by targeting CELF2. We identified miR­95­3p as a putative therapeutic target and CELF2 as a potential tumor suppressor.

High expression of forkhead box protein C2 is related to poor prognosis in human gliomas.

BACKGROUND: Increasing evidence has indicated that high Forkhead box protein C2 (FOXC2) level is closely associated with the development, progression, and poor prognosis of a variety of tumors. However, the relationship between FOXC2 and the progression of human gliomas remains to be clarified. The aim of present study was to assess FOXC2 expression and to explore its contribution in human gliomas. MATERIALS AND METHODS: Realtime quantitative PCR was performed to examine FOXC2 expression in 85 pairs of fresh frozen glioma tissues and corresponding non-neoplastic brain tissues. Associations of FOXC2 expression with clinicopathological factors and prognosis of glioma patients were statistically analyzed. RESULTS: The relative mRNA expression of FOXC2 was significantly higher in glioma tissues than the corresponding non-neoplastic brain tissues (p<0.001). In addition, high FOXC2 expression was significantly associated with advanced pathological grade (P=0.005) and the low Karnofsky performance score (KPS) (p=0.003), correlating with poor survival (p<0.001). Furthermore, multivariate Cox regression analysis showed that high FOXC2 expression was an independent predictor of overall survival (p=0.006). CONCLUSIONS: FOXC2 may act as an oncogenic gene and represent a potential regulator of aggressive development and a candidate prognostic marker in human gliomas.

Over-expression of wild-type p53-induced phosphatase 1 confers poor prognosis of patients with gliomas.

Wild-type p53-induced phosphatase 1 (Wip1) is a member of the protein phosphatase 2C family, which is characterized by distinctive oncogenic properties. Overexpression of Wip1 is observed in certain types of human tumors that are associated with significantly poor prognosis. This study aimed to detect the expression of Wip1 in gliomas and to analyze its prognostic value in the patients. Wip1 mRNA and protein expression profiles in 81 gliomas and 15 normal brain tissues were detected using RT-PCR, Western blot and immunohistochemistry. The specimens were stained with proliferating cell nuclear antigen (PCNA) and p53 and evaluated using immunohistochemistry. Detailed clinical and demographic information of patients were retrospectively collected until 5years post-operation. Kaplan-Meier survival and Cox's regression analyses were performed to evaluate the prognosis of patients. Wip1-positive expression was observed in the majority of glioma tissues, whereas no Wip1 expression was detected in the normal brain tissues. Wip1-positive expression significantly correlated with glioma histological grade. The PCNA index was higher in the Wip1-positive group compared to that in the Wip1-negative group. A univariate analysis and log-rank test indicated that statistically significant association between Wip1 expression and the lower overall survival rate in the patients with glioma. A multivariate analysis also indicated a statistically significant association between increased Wip1 expression and lower overall survival rate. Our results suggest that Wip1 may be related to pathological diagnosis and prognosis evaluation for malignant gliomas.

[The inhibition of tamoxifen on sodium channel in SHG-44 glioma cell-line].

AIM: To explore the effect of tamoxifen on voltage-dependent sodium channels in SHG-44 glioma cell line. METHODS: Whole-cell patch clamp technique was used to record the Na currents in SHG-44 cell line and to investigate the effect of tamoxifen of different concentration on this channel currents. RESULTS: This channel activated and inactivated quickly. Tamoxifen could significantly decrease the amplitude of Na currents of SHG-44 cell line. This block effect was dose dependent and voltage dependent. When the holding potential was 0 mV, 8 micromol/L tamoxifen could block this currents 69%. The half inhibition concentration (IC50) was 5.54 micromol/L. CONCLUSION: Tamoxifen could significantly block the voltage dependent sodium channel in malignant glioma cell line SHG-44. It might be one of the mechanisms that tamoxifen inhibit glioma proliferation. clamp technique was used to record the Na currents in SHG-44 cell line and to investigate the effect of tamoxifen of different concentration on this channel currents. RESULTS: This channel activated and inactivated quickly. Tamoxifen could significantly decrease the amplitude of Na currents of SHG-44 cell line. This block effect was dose dependent and voltage dependent. When the holding potential was 0 mV, 8 micromol/L tamoxifen could block this currents 69%. The half inhibition concentration (IC50) was 5.54 micromol/L. CONCLUSION: Tamoxifen could signifi-cantly block the voltage dependent sodium channel in malignant glioma cell line SHG-44. It might be one of the mechanisms that tamoxifen inhibit glioma proliferation.

[Correlations of polymorphisms in matrix metalloproteinase-3 and -7 promoters to susceptibility to brain astrocytoma].

BACKGROUND & OBJECTIVE: Matrix metalloproteinases (MMPs) are key enzymes involved in tumor development, invasion and metastasis. The single nucleotide polymorphisms (SNPs) in the promoter regions of MMP genes may influence tumor development and progression via modulating mRNA transcription and protein expression. This study was to explore the correlations of the promoter SNPs in MMP-3 and MMP-7 genes to susceptibility to brain astrocytoma. METHODS: The genotype of MMP-3 -1171 5A/6A and MMP-7 -181A/G polymorphisms in 236 patients with brain astrocytoma and 366 healthy controls was detected by polymerase chain reaction-restrictive fragment length polymorphism (PCR-RFLP). RESULTS: The allelotype and overall genotype distribution of MMP-3 SNP among the astrocytoma patients and healthy controls were similar (P>0.05). Stratified by sex, age, and histological grade, the susceptibility to brain astrocytoma among the subjects with 5A/5A and 5A/6A genotypes and the subjects with 6A/6A genotype were similar(P>0.05). The overall genotype distribution of MMP-7 SNP among the astrocytoma patients and healthy controls were significantly different (P = 0.001). Compared with the A/A genotype, both the G/G and the A/G genotypes significantly increased the susceptibility to astrocytoma [sex-and age-adjusted odds ratio (OR) = 2.77 and 1.69, 95% confidence interval (CI)=1.27-6.02 and 1.01-2.84, respectively]. Stratification analysis showed that the G/G genotype significantly increased the susceptibility to astrocytoma in men (adjusted OR = 3.24, 95% CI = 1.12-9.41) and in the individuals younger than 45 years (adjusted OR = 3.16, 95% CI = 1.09-9.16). When stratified by histological grade, the A/G genotype increased the susceptibility to grade II astrocytoma by about 2 folds (adjusted OR = 2.06, 95% CI = 1.05 - 4.05), while the G/G genotype increased the susceptibility to grade II-IV astrocytoma by about 3 folds. CONCLUSION: MMP-7 -181A/G polymorphism may influence the susceptibility to astrocytoma, while MMP-3-1171 5A/6A polymorphism has no correlation to the susceptibility.

[Anti-glioma activity of treatment by bone marrow stromal cells transfected with HSV-tk in the rat].

OBJECTIVE: To study the anti-glioma activity of treatment by bone marrow stromal cells (BMSCs) transfected with AdCMV-tk containing HSV-tk gene in rats. METHODS: Primary cultured BMSCs were obtained and transfected with HSV-tk (BMSCs/tk) and were injected into contralateral brain of glioma-bearing rats to observe their tropism for glioma cells. RT-PCR was performed to examine the transduct of tk gene after it was transduced into BMSCs. C6 glioma cells were co-cultured with BMSCs transfected with HSV-tk. MTT test was performed to examine its antitumor activity. BMSCs, after being transfected with HSV-tk, were injected into contralateral brain tissue of glioma-bearing rats to show their in vivo antitumor activity. Dynamic MRI was performed to monitor the development of intracranial glioma. RESULTS: Purified BMSCs were obtained by primary cultured bone marrow cells. After being transfected with HSV-TK, the cells still stably displayed extensive tropism for intracranial glioma and transcripted tk gene. RT-PCR showed that BMSCs/tk were transduced tk gene obviously at 21 days after AdCMV-tk transfection. BMSCs/tk showed a clear bystander effect after being co-cultured with C6 glioma cells in vitro. TUNEL assay showed that BMSCs/tk could obviously show bystander effect and induce apoptosis of glioma cells in vivo with an apoptosis positive ratio of 20.38% +/- 2.57%, showing a statistically significant difference in comparison with BMSCs group (2.56% +/- 0.52%, P = 0.023) and control group (2.74% +/- 0.38%, P = 0.025). Compared with the control group (21.40 +/- 1.63 days), BMSCs/tk transplantation significantly prolonged the survival time of glioma-bearing rats (52.60 +/- 13.11 days, P = 0.000). MRI detection showed that the least volume of intracranial glioma in BMSCs/tk group (8.28 +/- 2.64 mm3), significantly smaller than that in BMSCs group (134.51 +/- 16.37 mm3, P = 0.001) and control group (147.22 +/- 31.05 mm3, P = 0.001). Some of the intracranial gliomaa disappeared after transplantation of BMSCs/tk. CONCLUSION: BMSCs transfected with AdCMV-tk may become an effective therapy method in the treatment for glioma.

[Effect of bone marrow stromal cells transfected with interleukin 18 on growth of intracranial glioma in rats].

BACKGROUND & OBJECTIVE: Because of the invasion and immune escape characteristics, surgical resection, radiotherapy, and chemotherapy had no definite curative effects on intracranial glioma. Because bone marrow stromal cells (BMSCs) can track migrating cells, and interleukin 18 (IL-18) can enhance antitumor immune reaction, this study was to explore the effect of IL-18-transfected BMSCs on growth of glioma in rats. METHODS: Pure BMSCs were obtained by culturing rat bone marrow cells and identified by flow cytometry (FCM). BMSCs were transfected with retrovirus LXSN/IL-18 to prepare BMSCs/IL-18. IL-18 genetic transcription and expression were assessed by reverse transcription-polymerase chain reaction (RT-PCR) and immunofluorescence. The characteristic variations of BMSCs were detected by MTT assay, FCM, and immunofluorescence. The effect of BMSCs/IL-18 on activation of T cells was evaluated by ELISA. Glioma-bearing rats were divided into BMSCs group, BMSCs/IL-18 group, PBS group, and control group and received relevant treatments. The effect of BMSCs/IL-18 on growth of glioma was observed. RESULTS: IL-18 gene was expressed stably in BMSCs/IL-18. The proliferation speed of BMSCs/IL-18 was slower than that of BMSCs. The secretion of interferon-gamma (IFN-gamma) from rat spleen lymphocytes in BMSCs/IL-18 group was 9 times more than that in BMSCs group. Tumor volume was (18.26+/-6.84) mm(3) in BMSCs group, (6.37+/-1.52) mm(3) in BMSCs/IL-18 group, (22.48+/-6.02) mm(3) in PBS group, and (21.06+/-5.83) mm(3) in control group; survival time of the rats was (25.3+/-6.4) days, (84.7+/-16.3) days, (21.6+/-4.7) days, and (22.5+/-6.2) days, respectively. After transplantation of BMSCs/IL-18, CD4(+) T cells in glioma were increased to 37.7+/-3.5 and CD8(+) T cells were increased to 32.3+/-4.5 in each field of view (x200). CONCLUSION: BMSCs/IL-18 could express IL-18 gene stably, and have definite therapeutic effect on glioma in rats.

[Preliminary analysis on the gene expression profiles of medulloblastomas by use of cDNA array].

OBJECTIVE: To explore the molecular genesis of medulloblastomas with cDNA array. METHODS: Four samples of medulloblastomas and 1 sample of normal brain tissue were collected freshly. After total RNA extraction, the (32)P targeted cDNA probes were converted and then hybridized with Atlas Human Cancer Array 1.2. The gene expression profiles were acquired through autoradiography. The discrepancy between the tumor and the normal brain tissue was analyzed with Atlas Image 1.01a. RESULTS: In comparison with the genes in the normal brain tissue, 6 down-regulated and 35 up-regulated genes in the medulloblastomas were revealed by means of the microarrays and autoradiography, and were verified by reverse transcriptase-PCR. The regulatory trends of most differential expression genes were in compliance with the biological features of this tumor. CONCLUSION: Medulloblastomas are diseases involving multiple genes with some molecular pathological mechanisms different from the astrocytic gliomas. There are complex interrelationships between these genes, which need to be further researched.

[Preliminary study on the gene expression profiles of ependymomas with cDNA array].

OBJECTIVE: To investigate the differential gene expression of ependymomas. METHODS: Four fresh samples of ependymomas and 1 of normal brain tissue were collected during operation. The extracted total RNAs were converted as (32)P tagged cDNA probes, which were then hybridized with the Atlas Human Cancer Array, producing the array based hybridization maps following the protocol provided with the kit. A set of special software was applied to the analysis and RT-PCR was performed to test the result. RESULT: In comparison with the normal brain tissue, there were 31 upregulated gene and 1 downregulated gene in ependymomas, most of which were firstly found to be differentially expressed in this kind of tumor. CONCLUSION: The discrepancy of gene expression profiles between ependymomas and normal brain tissues is highly put through and effectively detected with cDNA array, which provides new information for the further research on the molecular mechanisms of this lesion.