Primary peripheral nerve lymphoma: a case report and literature review.

Neurolymphomatosis (NL) is an uncommon malignant lymphoma characterized by selective infiltration of the central and peripheral nervous system. In this case report, we present a patient diagnosed with diffuse large B-cell lymphoma who initially manifested with peripheral neuropathy, primarily characterized by weakness of the left lower limb. By exploring its clinical manifestations, ancillary tests, and reviewing the relevant literature, we aim to deepen our understanding, diagnosis, and treatment of this disease. A 48-year-old male patient presented to the Department of Neurology, Hematology, and Neurosurgery with complaint of left lower limb weakness that had persisted for over 11 months. Initial laboratory tests and cerebrospinal fluid analysis yielded negative results. Electromyography examination indicated damage to the left lumbar plexus and iliac plexus nerves raising suspicions of nerve root involvement. Enhanced MRI of the lumbosacral plexus nerves revealed thickening and enhanced signals in left nerve roots at T12-L1, L1-2, and L3-4 levels. Additionally, local thickening and enhancement of signals were observed in the left erector spine muscle, psoas major, and iliopsoas muscles compared to the contralateral side. PEC/CT imaging displayed multiple soft tissue density shadows in the left foraminal area at the T12-1 and L1-2 levels. Bone marrow examination excluded hematological disease. Subsequent biopsy of the left foraminal nerve root at T12-L1 and the vertebral muscle at L3 level confirmed a diagnosis of diffuse large B-cell malignant lymphoma, indicating PNSL due to the involvement of multiple nerve roots. Following diagnosis, the patient underwent chemotherapy, resulting in the alleviation of his symptoms. Diagnosing PNSL can be challenging due to the nonspecific clinical manifestations and often inconclusive laboratory test results. Misdiagnosis and delayed diagnosis are common pitfalls. Electromyography may reveal damage to the affected peripheral nerves, while MR imaging might show nerve root thickening, and PET/CT can demonstrate increased lesion uptake. However, the definitive diagnosis relies on a biopsy of the lesion. Treatment for PNSL typically involves chemotherapy.

The miR-29 family members induce glioblastoma cell apoptosis by targeting cell division cycle 42 in a p53-dependent manner.

BACKGROUND: Emerging evidence has shown that miR-29 is a promising biomarker and therapeutic target for malignancies. The roles of miR-29a/b/c in glioma pathogenesis remain need further investigation. METHODS: The expression levels of miR-29a/b/c and CDC42 were systematically analysed, and prognostic significance was evaluated by Kaplan-Meier survival and Cox regression analyses. The roles of miR-29a/b/c in apoptosis and the underlying mechanisms were explored via an alkaline single-cell gel electrophoresis assay, caspase 3/7 activity assays and Western blotting. RESULTS: miR-29a/b/c expression decreased progressively with the elevation of the WHO grade in our 147 human glioma specimens, compared with 20 non-tumour control brain tissues, and decreased miR-29a/b/c expression was associated with more aggressive phenotypes. Kaplan-Meier and Cox regression analyses demonstrated that lower miR-29a/b/c expression was correlated with worse prognosis, which was confirmed by analysis of 198 glioma patients from the CGGA cohort. These all indicate that miR-29a/b/c were independent predictors of prognosis in glioma patients. miR-29a/b/c induced apoptosis in GBM cells by silencing CDC42. Further detailed mechanistic investigation revealed that miR-29a/b/c promoted apoptosis in a p53-dependent manner by suppressing the CDC42/PAK/AKT/MDM2 pathway. CONCLUSIONS: miR-29a/b/c are independent predictors of prognosis in glioma patients. They induce glioblastoma cell apoptosis via silencing of CDC42 and suppression of downstream PAK/AKT/MDM2 signalling in a p53-dependent manner.

miR-135a-5p Functions as a Glioma Proliferation Suppressor by Targeting Tumor Necrosis Factor Receptor-Associated Factor 5 and Predicts Patients' Prognosis.

miR-135a-5p has been reported as a tumor suppressor in several extracranial tumors. However, its exact roles in gliomagenesis and relevance to the patients' prognoses are largely unknown. Herein, we detected the miR-135a-5p and tumor necrosis factor receptor-associated factor 5 (TRAF5) levels in 120 human glioma specimens and 20 nontumoral brain tissues; we found the miR-135a-5p level decreased, whereas the TRAF5 level increased, with the elevation of glioma grade. Their labeling indexes were inversely correlated with each other and showed strong negative (miR-135a-5p) and positive (TRAF5) correlation with the Ki-67 index. Cox regression demonstrated that both of their expression levels were independent survival predictors, whereas Kaplan-Meier analysis showed that subgrouping the glioma patients according to their levels could perfectly reflect the patients' prognoses regardless of the similarities in pathologic, molecular, and clinical features. In the following in vitro and in vivo studies, it was demonstrated that miR-135a-5p induced G1 arrest and inhibited the proliferation of glioma cells by targeting TRAF5 and subsequently blocking AKT phosphorylation as well as c-Myc and cyclin D1 expression. These effects could be reversed by TRAF5 overexpression and simulated by specific TRAF5 silencing. This study highlights the importance of miR-135a-5p and TRAF5 in gliomagenesis and progression and implies their potential prognostic and therapeutic values in malignant glioma.

miR-29a/b/c function as invasion suppressors for gliomas by targeting CDC42 and predict the prognosis of patients.

BACKGROUND: The lethality and poor outcome of high-grade gliomas result from the tumour relentless invasion. miR-29a/b/c downexpressions contribute to several human tumourigenesis. However, their relevance to prognosis and invasion in gliomas remains unclear. METHODS: Relationships of miR-29a/b/c and CDC42 expressions to grade and survival-time in 147 human gliomas were analysed by in situ hybridisation and immunohistochemistry. Dual-luciferase reporter assay was used to identify CDC42 as a target of miR-29a/b/c. Underlining mechanisms by which miR-29a/b/c inhibited glioma cell migration and invasion were studied by in vitro and in vivo assays. RESULTS: miR-29a/b/c expressions were inversely correlated with glioma grades, but positively correlated with patients' survival. Two distinct subgroups of grade I-IV glioma patients with different prognoses were identified according to miR-29a/b/c expressions. miR-29a/b/c overexpressions suppressed glioma cell migration and invasion through targeting CDC42 and subsequently decreasing phosphorylated PAK1/2/3, LIMK1/2 and cofilin, the pivotal downstream effectors of CDC42. Moreover, CDC42 expression was positively correlated with glioma grades, but inversely correlated with miR-29a/b/c expressions and patients' survival. In glioblastoma cell lines, CDC42-knockdown could mimic the anti-tumour effects of miR-29a/b/c. CONCLUSIONS: miR-29a/b/c are important tumour suppressors and novel prognostic biomarkers of gliomas, and miR-29a/b/c and CDC42 are potential therapeutic candidates for malignant gliomas.

Identification of SRSF10 as a promising prognostic biomarker with functional significance among SRSFs for glioma.

AIMS: The serine/arginine-rich splicing factor (SRSF) protein family members are essential mediators of the alternative splicing (AS) regulatory network, which is tightly implicated in cancer progression. However, the expression, clinical correlation, immune infiltration, and prognostic value of SRSFs in gliomas remain unclear. MATERIALS AND METHODS: Glioma samples were extracted from The Cancer Genome Atlas (TCGA) and Chinese Glioma Genome Atlas (CGGA) datasets. Several databases, such as HPA, DAVID, UALCAN were used to comprehensively explore the roles of SRSFs. In addition, experimental validation of SRSF10 was also conducted. KEY FINDINGS: Here, we found the expression alterations of the SRSF family in glioma samples using data from the TCGA and CGGA_325 datasets. Among the 12 genes, most were found to be closely associated with glioma clinical features, which linked to poor prognosis in glioma patients. Interestingly, survival analysis identified only SRSF10 as a potential independent risk prognostic biomarker for glioma patients. Immune analysis indicated that glioma patients with high SRSF10 expression may respond well to immunotherapies targeting immune checkpoint (ICP) genes. Finally, knocking down SRSF10 reduced glioma cell viability, induced G1 cell cycle arrest, and induced the exclusion of bcl-2-associated transcription factor 1 (BCLAF1) exon 5a. SIGNIFICANCE: Overall, this study uncovers the oncogenic roles of most SRSF family members in glioma, with the exception of SRSF5, while highlighting SRSF10 as a potential novel independent prognostic biomarker for glioma.

Supratentorial Collision Tumor of Hemangioblastoma and Metastatic Clear Cell Renal Cell Carcinoma in a Patient with von Hippel-Lindau Disease.

Collision tumors are rarely reported in patients with von Hippel-Lindau (VHL) disease, even though VHL patients often present with multi-organ tumor syndromes, like hemangioblastoma and renal cell carcinoma (RCC). Hemangioblastoma is rarely located in a supratentorial location, and intracranial lateral ventricular is also not a common site of metastasis for RCC. It is extremely rare for the two tumors to collide in the supratentorial area. We report a 64-year-old man with a history of clear cell RCC who presented with a sudden headache. The brain magnetic resonance imaging revealed that there was a cystic-solid mass in the intracranial lateral ventricular trigone. Histopathologically, the tumor consisted of two distinct components, most of which showed the typical morphology of hemangioblastoma. However, there were a few acinar structures composed of clear cells scattered in hemangioblastoma, and these acinar structures were subsequently confirmed as clear cell RCC. The genetic testing confirmed that the patient had VHL disease with de novo somatic mutation. Based on our case report, we systematically reviewed the characteristics of collision tumor composed of hemangioblastoma and metastatic RCC in VHL patients. The special growth site of our case is the first report of this kind of collision tumor, and can also help enrich our understanding of VHL disease and collision tumor.

The putative tumor suppressor miR-524-5p directly targets Jagged-1 and Hes-1 in glioma.

Notch pathway plays critical role in stem cell maintenance and angiogenesis, as well as cell fate decisions of cancer. However, concrete mechanisms of notch pathway regulation in glioma were not well known, especially mediated by microRNAs. In this study, we identified a brain-specific miRNA, miR-524-5p, which was associated with the pathological grade and overall survival of gliomas. Restorated expression of miR-524-5p in glioma suppressed cell proliferation and invasion both in vitro and in vivo. Using bioinformatics and biological approaches, we found that Jagged-1 and Hes-1, two key components of notch pathway, were direct targets of miR-524-5p. Knocking down of Jagged-1 or Hes-1 partially phenocopied miR-524-5p re-expression, whereas forced expression of Jagged-1 or Hes-1 reversed the effects of miR-524-5p on proliferation and invasion of glioma. Moreover, miR-524-5p levels in glioma samples were inversely correlated with Jagged-1 and Hes-1 and their overexpressions were associated with poor survival. Thus, we have identified that miR-524-5p behaves as a tumor suppressor by negatively targeting Jagged-1 and Hes-1 and provides an additional option to inhibit this oncogene in gliomas.

High level of miR-221/222 confers increased cell invasion and poor prognosis in glioma.

BACKGROUND: MiR-221 and miR-222 (miR-221/222), upregulated in gliomas, can regulate glioma cell cycle progression and apoptosis, respectively. However, the association of miR-221/222 with glioma cell invasion and survival remains unknown. METHODS: Invasion capability of miR-221/222 was detected by mutiple analyses, including diffusion tensor imaging (DTI), transwell, wound healing and nude mouse tumor xenograft model assay. Further, the target of miR-221/222 was determined by luciferase reporter, western blot and gene rescue assay. The association of miR-221/222 with outcome was examined in fifty glioma patients. RESULTS: MiR-221/222 expression was significantly increased in high-grade gliomas compared with low-grade gliomas, and positively correlated with the degree of glioma infiltration. Over-expression of miR-221/222 increased cell invasion, whereas knockdown of miR-221/222 decreased cell invasion via modulating the levels of the target, TIMP3. Introduction of a TIMP3 cDNA lacking 3' UTR abrogated miR-221/222-induced cell invasion. In addition, knockdown of miR-221/222 increased TIMP3 expression and considerably inhibited tumor growth in a xenograft model. Finally, the increased level of miR-221/222 expression in high-grade gliomas confers poorer overall survival. CONCLUSIONS: The present data indicate that miR-221 and miR-222 directly regulate cell invasion by targeting TIMP3 and act as prognostic factors for glioma patients.

Recruitment of LEF1 by Pontin chromatin modifier amplifies TGFBR2 transcription and activates TGFß/SMAD signalling during gliomagenesis.

Synergies of transcription factors, chromatin modifiers and their target genes are vital for cell fate determination in human cancer. Although the importance of numerous epigenetic machinery for regulating gliomagenesis has been previously recognized, how chromatin modifiers collaborate with specific transcription factors remains largely elusive. Herein we report that Pontin chromatin remodelling factor acts as a coactivator for LEF1 to activate TGFß/SMAD signalling, thereby contributing to gliomagenesis. Pontin is highly expressed in gliomas, and its overexpression paralleled the grade elevation and poor prognosis of patients. Functional studies verified its oncogenic roles in GBM cells by facilitating cell proliferation, survival and invasion both in vitro and in vivo. RNA sequencing results revealed that Pontin regulated multiple target genes involved in TGFß/SMAD signalling. Intriguingly, we found that Pontin amplified TGFßR2 gene transcription by recruiting LEF1, thereby activating TGFß/SMAD signalling and facilitating gliomagenesis. Furthermore, higher TGFßR2 expression conferred worse patient outcomes in glioma. To conclude, our study revealed that the Pontin-LEF1 module plays a crucial role in driving TGFßR2 gene transcription, which could be exploited to target TGFß/SMAD signalling for anti-glioma therapy.

[Relationship between miR-218 and CDK6 expression and their biological impact on glioma cell proliferation and apoptosis].

OBJECTIVES: To investigate the relationship between the expression of miR-218 and CDK6 in glioma cells, and their biological impacts on the tumor cell proliferation and apoptosis. METHODS: Expression levels of miR-218 as well as CDK6 and Ki-67 proteins were analyzed in 60 cases of gliomas with various grades and 10 control brain tissue samples by tissue microarray, locked oligonucleotide probe in situ hybridization and immunohistochemistry. Glioblastoma multiform cell line (U87MG) was transfected with miR-218 mimics (mimics group) and a control sequence (control group), followed by qRT-PCR detection of miR-218 and immunocytochemical stain of CDK6 and Ki-67, respectively. Single cell gel electrophoresis was used to detect the presence of apoptotic cell. RESULTS: The miR-218 labeling indexes (LI) were statistically different (P<0.05) among all groups including control (22.45 +/- 0.59) and various glioma groups (grades I - II 4.00 +/- 1.07, grade III 1.87 +/- 1.06 and grade IV 0.94 +/- 0.78, respectively). The CDK6 LI of the four groups was 7.25 +/- 1.20, 16.71 +/- 0.80, 24.43 +/- 0.62 and 32.05 +/- 0.43, respectively. Significant differences existed between the control group and the glioma groups, and between grade IV and grades I - II glioma groups (P<0.01). Ki-67 positive cell densities of the above four groups (0.00 +/- 0.00, 9.30 +/- 3.48, 31.15 +/- 9.44 and 60.15 +/- 13.60) were significantly different from one and another (P<0.01). The expression of miR-218 negatively correlated with CDK-6 LI (r = -0.480, P<0. 01) and Ki-67 positive cell density (r = - 0.534, P<0.01), while the latter two positively correlated with each other (r = 0.530, P<0.01). U87MG transfection experiment showed that the miR-218 level of the mimics group was significantly higher than that of the control group (P<0.01). CDK6 and Ki-67 LI of the mimics group (14.74 +/- 1.19 and 30.88 +/- 3.31) were significantly lower than those of the control group (79.06 +/- 2.07 and 64.94 +/- 3.96, P<0.01), whilst its apoptotic index (AI) (68.44 +/- 7.05) was significantly higher than that of the control group (13.04 +/- 0.97, P<0.01). CONCLUSIONS: The expression level of miR-218 is an important reference indicator for the assessment of the grade of gliomas. An aberrant decrease of its expression may lead to an increase of the CDK6 expression and proliferative activity of giloma cells. Introducing exogenous miR-218 may effectively down-regulate the CDK6 expression, inhibit cell proliferation and induce apoptosis of malignant giloma cells. These findings imply that miR-218 may serve as a therapeutic agent against malignant glioma.

Improved Antiglioblastoma Activity and BBB Permeability by Conjugation of Paclitaxel to a Cell-Penetrative MMP-2-Cleavable Peptide.

In order to solve the problems of receptor promiscuity and poor blood-brain barrier (BBB) penetration in the treatment of glioblastomas (GBM), a novel dual-functional nanocomplex drug delivery system is developed based on the strategy of peptide-drug conjugates. In this study, SynB3-PVGLIG-PTX is designed and screened out by matrix metalloproteinase-2 (MMP-2), to which it exhibits the best affinity. The MMP-2-sensitive peptide (PVGLIG) and a cell-penetration peptide (SynB3) are combined to form a dual-functional peptide. Moreover, as a drug-peptide nanocomplex, SynB3-PVGLIG-PTX exhibited a high potential to form an aggregation with good solubility that can release paclitaxel (PTX) through the cleavage of MMP-2. From a functional perspective, it is found that SynB3-PVGLIG-PTX can specifically inhibit the proliferation, migration, and invasion of GBM cells in vitro in the presence of MMP-2, in contrast to that observed in MMP-2 siRNA transfected cells. Further investigation in vivo shows that SynB3-PVGLIG-PTX easily enters the brain of U87MG xenograft nude mice and can generate a better suppressive effect on GBM through a controlled release of PTX from SynB3-PVGLIG-PTX compared with PTX and temozolomide. Thus, it is proposed that SynB3-PVGLIG-PTX can be used as a novel drug-loading delivery system to treat GBM due to its specificity and BBB permeability.

The ATPase Pontin is a key cell cycle regulator by amplifying E2F1 transcription response in glioma.

Pontin (RUVBL1) is a highly conserved ATPase of the AAA + (ATPases Associated with various cellular Activities) superfamily and is implicated in various biological processes crucial for oncogenesis. Its overexpression is observed in multiple human cancers, whereas the relevance of Pontin to gliomagenesis remains obscure. To gain insights into Pontin involvement in glioma, we performed bioinformatics analyses of Pontin co-expressed genes, Pontin-affected genes, and carried out experimental studies. The results verified that Pontin was upregulated in gliomas. Its higher levels might predict the worse prognosis of glioma patients. The Pontin co-expressed genes were functionally enriched in cell cycle progression and RNA processing. In the nucleus, Pontin promoted cell growth via facilitating cell cycle progression. Using RNA-seq, we found that Pontin knockdown resulted in altered expression of multiple genes, among which the E2F1 targets accounted for a large proportion. Mechanistic studies found that Pontin interacted with E2F1 and markedly amplified the E2F1 transcription response in an ATPase domain-dependent manner. By analyzing the RNA-seq data, we also found that Pontin could impact on the alternative splicing (AS). Both differential expressed genes and AS events affected by Pontin were associated with cell cycle regulation. Taken together, our findings provide novel insights of the importance of Pontin in gliomagenesis by regulating cell cycle and AS, and shed light on the possible application of Pontin as an antineoplastic target in glioma.

Eucalyptal A inhibits glioma by rectifying oncogenic splicing of MYO1B mRNA via suppressing SRSF1 expression.

Glioma is the most common primary intracranial tumor, in which glioblastoma (GBM) is the most malignant and lethal. However, the current chemotherapy drugs are still unsatisfactory for GBM therapy. As the natural products mainly extracted from Eucalyptus species, phloroglucinol-terpene adducts have the potential to be anti-cancer lead compounds that attracted increasing attention. In order to discover the new lead compounds with the anti-GBM ability, we isolated Eucalyptal A with a phloroglucinol-terpene skeleton from the fruit of E. globulus and investigated its anti-GBM activity in vitro and in vivo. Functionally, we verified that Eucalyptal A could inhibit the proliferation, growth and invasiveness of GBM cells in vitro. Moreover, Eucalyptal A had the same anti-GBM activity in tumor-bearing mice as in vitro and prolonged the overall survival time by maintaining mice body weight. Further mechanism research revealed that Eucalyptal A downregulated SRSF1 expression and rectified SRSF1-guided abnormal alternative splicing of MYO1B mRNA, which led to anti-GBM activity through the PDK1/AKT/c-Myc and PAK/Cofilin axes. Taken together, we identified Eucalyptal A as an important anti-GBM lead compound, which represents a novel direction for glioma therapy.

Overexpression of septin 7 suppresses glioma cell growth.

Our previous study demonstrated that SEPT7 was downregulated at mRNA level in human gliomas. This study is to further examine the expression of SEPT7 in glioma samples and characterizes its role on cell cycle progression and growth of glioma cells. mRNA and protein expression of SEPT7 were detected by RT-PCR, immunohistochemical staining, and western blot analysis in human glioma specimens and normal brain tissues. A pcDNA3-SEPT7 expression plasmid was constructed and transfected into human glioblastoma cell line U251, and cell proliferation and apoptosis were examined. The growth of established U251 and TJ905 subcutaneous xenograft gliomas was measured in nude mice treated with pcDNA3-SEPT7 and U251 xenograft tumors treated with SEPT7 siRNA. SEPT7 expression is negatively correlated with the increase of glioma grade. Overexpression of SEPT7 is able to inhibit cell proliferation and arrest cell cycle progression in the G0/G1 phase both in vitro and in vivo. Knocking down further the already low endogenous expression of SEPT7 in U251 xenograft tumors with siRNA leads to faster tumor growth compared with control tumors. This study demonstrates that SEPT7 is involved in gliomagenesis and suppresses glioma cell growth.

[Detection of chromosomal DNA imbalance in medulloblastoma by comparative genomic hybridization].

OBJECTIVE: To investigate the relationship between chromosomal genomic DNA imbalance in medulloblastoma (MB), and the age and gender. METHODS: The gains and losses of chromosomal genomic DNA in 16 MBs were analyzed using comparative genomic hybridization. RESULTS: The gains and(or) losses were found in 15 of the 16 cases. There was not significant difference (P > 0.05) between the total gains (10/16) and losses (11/16). Both of their differences had also no significance between different age and gender groups (P > 0.05). In 15 cases with gains and(or) losses, single-, two-, three- and multi-chromosome genomic DNA imbalances were 3/15, 4/15, 1/15 and 7/15 respectively. Eleven gain zones (+5q, +6q, +7q, +11q, +15q, +17p, +17q, +19q, +20q, +21q, +Xp) and twenty-five loss zones (-1p, -1q, -2p, -2q, -3q, -4p, -6p, -6q, -8p, -8q, -10p, -10q, -11p, -14q, -16p, -16q, -17p, -18p, -18q, -19p, -19q, -20p, -20q, -Xp, -Xq) were detected in those tumors. +7q (6/16), +17q (6/16), -14q (5/16) and -10q (3/16) were the most frequent, but -14q only occurred in the cases of > 10-year-old. CONCLUSIONS: Most MBs have chromosomal genomic DNA imbalances. The frequent imbalance zones are mainly at the long arms of some chromosomes. +7q, +17q, -14q and -10q correlate closely to development of the tumors. -14q is important factor to result in MBs of > 10-year-old group. MB has possibly different molecular genetics subtype.

[Effects of azidothymidine on p33ING1b expression, apoptosis and senescence of TJ905 human glioblastoma cell line].

OBJECTIVES: To investigate the pharmacological effects of azidothymidine (AZT) on p33ING1b expression, senescence and apoptosis of TJ905 glioblastoma cells. METHODS: TJ905 cells were treated with AZT at a serial concentrations of 50, 100 and 200 µmol/L. Semi-quantitative RT-PCR and cytochemical staining of senescence related-galactosidase (sß-Gal) were used to evaluate the expression of p33ING1b mRNA and to label the senescent cells at the 1st, 3rd and 6th generations, respectively. In situ cell death detection and single cell gel electrophoresis were used to detect the apoptosis at the 3rd and 6th generations. RESULTS: AZT induced the expression of p33ING1b mRNA and senescence of the tumor cells of the 1st generation in a dosage and time dependent manner. At the 6th generation, the relative amount of p33ING1b RT-PCR product (1.44±0.23) and sß-Gal labeling index of 200 µmol/L group (45.62±6.74) were significantly higher than those of the 1st (0.95±0.13 and 7.82±2.40) and the 3rd generation cells (1.35±0.23, 26.27±7.17) of the same group, and cells of the same generation in the 50 µmol/L (0.85±0.24, 27.37±6.41) and 100 µmol/L groups (1.23±0.34, 35.49±5.12, P<0.01). There was a significant positive correlation between the p33ING1b mRNA expression and the labeling index of sß-Gal. Pro-apoptotic effects of AZT became obvious at the 6th generation. CONCLUSION: AZT upregulates the expression of p33ING1b, a possible mechanism in regulating senescence and apoptosis of the TJ905 cells.

Growth inhibition against intracranial C6 glioma cells by stereotactic delivery of BCNU by controlled release from poly(D,L-lactic acid) nanoparticles.

Transferrin (Tf), an iron-transporting serum glycoprotein, which binds to receptors expressed at the surface of most proliferating cells with particularly high expression on erythroblasts and cancer cells, was chosen as the ligand to develop BCNU-loaded biodegradable poly(D,L-lactic acid) nanoparticles (NPs) containing a ligand, which specifically binds to glioma cells, and their anti-tumor ability was evaluated using a C6 glioma model. In vitro drug release behavior demonstrated that BCNU-loaded PLA NPs show certain sustained release characteristics. NPs with low molecular weight PLA showed a higher burst effect and a significantly faster drug release from PLA samples. The biodistribution of Tf-coated nanoparticles investigated by 99Tc-labeled SPECT showed that the surface-containing transferrin PLA nanoparticles were concentrated in the brain and no radioactive foci could be found outside the brain. Inhibition of tumor growth in the C6 tumor-bearing animal model showed that BCNU-loaded PLA NPs had stronger cytotoxicity and prolonged the average survival time of rats. Especially when treated at an early stage with a higher dosage of NPs, the average survival time of rats was prolonged 88.37%. Furthermore, one rat maintained normal behavior continuously for an observation period of up to 60 days.

[Detection of chromosomal imbalance in ependymoma by comparative genomic hybridization].

OBJECTIVE: To investigate genomic DNA imbalances in ependymomas (EDMs) and their correlations with the tumor histological types, grades, locations, patients' gender and age. METHODS: Chromosomal gains and losses in 16 cases of EDM were analyzed using comparative genomic hybridization. RESULTS: Chromosomal regional gain and loss were found in 15 and 13 of 16 EDM cases respectively including totally 24 regional gains and 19 regional losses in all the tumors studied. Both regional gains and losses were mostly seen in myxopapillary EDMs (MPE, WHO grade I), more commonly seen in cellular EDMs (CE, WHO grade II) and tanycytic EDMs (TE, WHO grade II) than in anaplastic EDMs (AE, WHO grade III). Some of the regional gains and losses appeared only in one subtype of MPE, CE, TE and AE cases resulting in development of specific imbalance profiles of certain subtype in these cases. MPE, CE and TE often had +7. Chromosomal +5 occurred only in MPE and CE, and -22q was only seen in CE and TE. AE frequently had +1q, but none had +5, +7, -4q, -19q and -22q. The frequencies of any regional gain or loss were not affected by patients' genders (P > 0.05). Chromosomal +1q and +7p happened predominantly in intracranial EDMs with an averagely onset age of

[Azidothymidine inhibition of telomerase activity and proliferation of TJ905 human glioblastoma cells].

OBJECTIVE: To investigate the pharmacological effects and underlying mechanism of azidothymidine (AZT) on human glioblastoma cells in vitro. METHODS: The telomerase activity of human glioblastoma TJ905 cells was determined by TRAP assay after 24 hrs' incubation with 50, 100, 200 micromol/L AZT and control vehicle solution. Colony formation efficiencies of the cells were recorded. Cells of the 1st, 3rd and 6th generations were harvested, followed by evaluations of cyclin A protein expression by Western blot, cell cycle distribution by flow cytometry, apoptotic level by single cell gel electrophoresis and proliferation index by Ki-67 immunocytochemical staining. RESULTS: AZT inhibited telomerase activity of TJ905 cells. Cyclin A expression levels in the cells treated with 50 and 100 micromol/L AZT were significantly lower than controls (P < 0.01), and down-regulation of the expression was in a dose- and time-dependent manner. Compared with controls, G(0)/G(1) phase cells were obviously decreased (P < 0.05 approximately 0.01) and S phase cells significantly increased (P < 0.05 approximately 0.01) after treatment with 50, 100 and 200 micromol/L AZT. The cell numbers of G(0)/G(1) and S phases at the 1st generation of above three treated groups changed in a dose-dependent manner, whereas S phase cells increases in all AZT treatment groups and G(0)/G(1) phase cell decrease in group treated with 50 micromol/L AZT were also in a time-dependent manner. Both the apoptotic cells of the 1st and 6th generations of all AZT treatment groups were significantly more than controls (P < 0.05 approximately 0.01), their numbers of the 6th generations of the three groups increased with AZT concentration (P < 0.05 approximately 0.01), and all of them were more than the 1st and 3rd generations of the same dosage group (P < 0.05 approximately 0.01). Colony formation efficiencies and Ki-67 labeling indexes of the three AZT treatment groups were distinctly lower than controls (P < 0.01), and they were also decreased with the elevation of AZT concentration and/or the elongation of the incubating time. The difference of any above parameter had no significance among the 1st, 3rd and 6th generations of control group (P > 0.05). CONCLUSION: AZT blocks S/G(2) conversion of TJ905 cells by inhibition of telomerase activity and cyclin A expression, leading to an enhancement of apoptosis and suppression of cell proliferation.