Downregulation of VEGF expression attenuates malignant biological behavior of C6 glioma stem cells

Synthesis and Antitumour Evaluation of Tricyclic Indole-2-Carboxamides against Paediatric Brain Cancer Cells

Antitumour properties of some cannabinoids (CB) have been reported in the literature as early as 1970s, however there is no clear consensus to date on the exact mechanisms leading to cancer cell death. The indole-based WIN 55,212-2 and SDB-001 are both known as potent agonists at both CB1 and CB2 receptors, yet we demonstrate herein that only the former can exert in vitro antitumour effects when tested against a paediatric brain cancer cell line KNS42. In this report, we describe the synthesis of novel 3,4-fused tricyclic indoles and evaluate their functional potencies at both cannabinoid receptors, as well as their abilities to inhibit the growth or proliferation of KNS42 cells. Compared to our previously reported indole-2-carboxamides, these 3,4-fused tricyclic indoles had either completely lost activities, or, showed moderate-to-weak antagonism at both CB1 and CB2 receptors. Compound 23 displayed the most potent antitumour properties among the series. Our results further support the involvement of non-CB pathways for the observed antitumour activities of amidoalkylindole-based cannabinoids, in line with our previous findings. Transcriptomic analysis comparing cells treated or non-treated with compound 23 suggested the observed antitumour effects of 23 are likely to result mainly from disruption of the FOXM1-regulated cell cycle pathways.

In vivo C6 glioma models: an update and a guide toward a more effective preclinical evaluation of potential anti-glioblastoma drugs

Glioblastoma multiform (GBM) is the most common primary brain tumor with a poor prognosis and few therapeutic choices. In vivo, tumor models are useful for enhancing knowledge of underlying GBM pathology and developing more effective therapies/agents at the preclinical level, as they recapitulate human brain tumors. The C6 glioma cell line has been one of the most widely used cell lines in neuro-oncology research as they produce tumors that share the most similarities with human GBM regarding genetic, invasion, and expansion profiles and characteristics. This review provides an overview of the distinctive features and the different animal models produced by the C6 cell line. We also highlight specific applications of various C6 in vivo models according to the purpose of the study and offer some technical notes for more convenient/repeatable modeling. This work also includes novel findings discovered in our laboratory, which would further enhance the feasibility of the model in preclinical GBM investigations.

Engineering antibody and protein therapeutics to cross the blood-brain barrier

Diseases in the central nervous system (CNS) are often difficult to treat. Antibody- and protein-based therapeutics hold huge promises in CNS disease treatment. However, proteins are restricted from entering the CNS by the blood-brain barrier (BBB). To achieve enhanced BBB crossing, antibody-based carriers have been developed by utilizing the endogenous macromolecule transportation pathway, known as receptor-mediated transcytosis. In this report, we first provided an overall review on key CNS diseases and the most promising antibody- or protein-based therapeutics approved or in clinical trials. We then reviewed the platforms that are being explored to increase the macromolecule brain entry to combat CNS diseases. Finally, we have analyzed the lessons learned from past experiences and have provided a perspective on the future engineering of novel delivery vehicles for antibody- and protein-based therapies for CNS diseases.

Therapeutic Perspective of Temozolomide Resistance in Glioblastoma Treatment

Glioblastoma (GB) is the most lethal form of primary brain neoplasm. TMZ is the first-line standard treatment, but the strong resistance constrains the efficacy in clinical use. GB contains glioma stem cells (GSCs), which contribute to TMZ resistance, promote cell survival evolvement, and repopulate the tumor mass. This review summarizes the TMZ-resistance mechanisms and discusses several potential therapies from the conservative opinion of GSC-targeted therapy orientation to the current view of TMZ resistance-aimed efficacy, which will provide an understanding of the role of heterogeneity in drug resistance and improve therapeutic efficacy in general.

Glioblastoma Multiforme: An Overview of Emerging Therapeutic Targets

Glioblastoma multiforme (GBM) is the most common and aggressive malignant primary brain tumour in humans and has a very poor prognosis. The existing treatments have had limited success in increasing overall survival. Thus, identifying and understanding the key molecule(s) responsible for the malignant phenotype of GBM will yield new potential therapeutic targets. The treatment of brain tumours faces unique challenges, including the presence of the blood brain barrier (BBB), which limits the concentration of drugs that can reach the site of the tumour. Nevertheless, several promising treatments have been shown to cross the BBB and have shown promising pre-clinical results. This review will outline the status of several of these promising targeted therapies.

Overexpression of the Kininogen-1 inhibits proliferation and induces apoptosis of glioma cells

Background

Glioma is the most common primary central nervous system tumor derived from glial cells. Kininogen-1 (KNG1) can exert antiangiogenic properties and inhibit proliferation of endothelial cells. The effect of KNG1 on the glioma is rarely reported, so our purpose in to explore its mechanism in glioma cells.

Methods

The differentially expressed genes (DEGs) were identified based on The Cancer Genome Atlas (TCGA) database. The KNG1-vector was transfected into the two glioma cells. The viability, apoptosis and cell cycle of glioma cells and microvessel density (MVD) were detected by cell counting kit-8 assay, flow cytometry and immunohistochemistry, respectively. The expression were measured by quantitative real-time PCR and Western blot, respectively. A tumor mouse model was established to determine apoptosis rate of brain tissue by terminal deoxynucleotidyl transfer-mediated dUTP nick end labeling (TUNEL) analysis.

Results

KNG1 was identified as the core gene and lowly expressed in the glioma cells. Overexpression of KNG1 inhibited cell viability and angiogenesis of glioma cells. Overexpression of KNG1 promoted the apoptosis and G1 phase cell cycle arrest of glioma cells. Moreover, the expressions of VEGF, cyclinD1, ki67, caspase-3/9 and XIAP were regulated by overexpression of KNG1. In addition, overexpression of KNG1 inhibited the activity of PI3K/Akt. Furthermore, overexpression of KNG1 decreased the tumor growth and promoted the apoptosis of decreased by overexpression of KNG1 in vivo. .

Conclusions

Overexpression of KNG1 suppresses glioma progression by inhibiting the proliferation and promoting apoptosis of glioma cells, providing a therapeutic strategy for the malignant glioma.

A case report of targeted therapy with apatinib in a patient with recurrent high grade glioma

RATIONALE

Despite the approval of antiangiogenic therapy for high grade glioma (HGG) patients, survival benefits are still limited. New treatment plans have always been developed to improve the survival.

PATIENT CONCERNS

A 26-year-old woman was admitted to our hospital for distending pain of head and eye.

DIAGNOSES

Resonance imaging (MRI) revealed a large spherical heterogeneously enhancing, mixed cystic and solid mass in the right frontal region, and the midline shifted.

INTERVENTION

The patient received apatinib therapy for positive vascular endothelial growth factor.

OUTCOMES

A partial response was observed after 4 weeks and remains sustained until now.

LESSONS

It suggests that apatinib might be a feasible option for the treatment in advanced HGG patients or patients with poor physical condition.

Downregulation of SIRT6 is associated with poor prognosis in patients with non-small cell lung cancer

Objective

To explore the prognostic significance of nicotinamide adenine dinucleotide (NAD)-dependent protein deacetylase sirtuin-6 (SIRT6), encoded by the sirtuin 6 (SIRT6) gene, in a population of Chinese Han patients with non-small cell lung cancer (NSCLC).

Methods

Cancer tissues and normal lung tissues (>5 cm adjacent to cancer tissue) were collected from Chinese Han patients with NSCLC. Expression levels of SIRT6 and histone H3-acetyl K56 (H3K56), in cancer and normal lung tissues from patients with NSCLC, were detected by reverse-transcription polymerase chain reaction, Western blot and immunohistochemistry. Correlations between SIRT6 expression and various clinicopathologic features were investigated.

Results

Out of 86 patients included in the study, mRNA and protein SIRT6 levels were down-regulated in NSCLC tissue versus normal lung tissue, and SIRT6 levels were inversely correlated with H3K56 levels. Positive rates of SIRT6 were significantly correlated with degree of cell differentiation, TNM stage, lymph node metastasis, overall survival and metastasis-free survival.

Conclusion

Downregulation of SIRT6 expression may promote NSCLC malignancy in the Chinese Han population. SIRT6 may be a potential therapeutic target in Chinese Han patients with NSCLC.

IDH1 mutation diminishes aggressive phenotype in glioma stem cells

The R132H mutation in isocitrate dehydrogenase 1 (IDH1-R132H) is associated with better prognosis in glioma patients. Glioma stem cells (GSCs) in glioma are believed to be responsible for glioma growth and maintenance. However, the relation between the R132H mutation and GSCs is not fully understood. In the present study, GSC markers were detected in patients with IDH1-R132H or wild-type IDH1 (IDH1-wt) by tissue microarray immunohistochemistry (TMA-IHC). The relationship between the expression patterns of GSC markers and the clinicopathological characteristics in glioma were analyzed. To confirm this mutation's role in GSCs, the IDH1-R132H in GSCs isolated from glioblastoma patients with IDH1 mutations was overexpressed by using lentiviral constructs in vitro, and then the proliferation, differentiation, apoptosis, migration and invasion of the transfected GSCs were explored. At the molecular level, we detected Wnt/β-catenin signaling expression to verify its role in regulating the cellular properties of GSCs. The results showed that the positive rate of GSCs in patients with IDH1-R132H was significantly less than that in patients with IDH1-wt. The positive rate of GSCs was correlated with IDH1 mutation, TNM stage and poor overall survive. After transfection in vitro, IDH1-R132H overexpression led to reduced GSCs proliferation, migration and invasion, inducing apoptosis and improving GSC differentiation, accompanied by a significant reduction in activity of β-catenin. Several mediators, effectors and targets of the Wnt/β-catenin signaling were downregulated. The data demonstrate that IDH1 mutation reduces the malignant progression of glioma by causing a less aggressive phenotype of GSCs which are involved in the Wnt/β‑catenin signaling.

Glioblastoma stem-like cells secrete the pro-angiogenic VEGF-A factor in extracellular vesicles

Glioblastoma multiforme (GBM) are mortifying brain tumours that contain a subpopulation of tumour cells with stem-like properties, termed glioblastoma stem-like cells (GSCs). GSCs largely contribute to tumour initiation, propagation and resistance to current anti-cancer therapies. GSCs are situated in perivascular niches, closely associated with brain microvascular endothelial cells, thereby involved in bidirectional molecular and cellular interactions. Moreover, extracellular vesicles are suspected to carry essential information that can adapt the microenvironment to the tumour’s needs, including tumour-induced angiogenesis. In GBM, extracellular vesicles produced by differentiated tumour cells and GSCs were demonstrated to disseminate locally and at distance. Here, we report that the pro-angiogenic pro-permeability factor VEGF-A is carried in extracellular vesicles secreted from ex vivo cultured patient-derived GSCs. Of note, extracellular vesicle-derived VEGF-A contributes to the in vitro elevation of permeability and angiogenic potential in human brain endothelial cells. Indeed, VEGF-A silencing in GSCs compromised in vitro extracellular vesicle-mediated increase in permeability and angiogenesis. From a clinical standpoint, extracellular vesicles isolated from circulating blood of GBM patients present higher levels of VEGF-A, as compared to healthy donors. Overall, our results suggest that extracellular vesicle-harboured VEGF-A targets brain endothelial cells and might impact their ability to form new vessels. Thus, tumour-released EV cargo might emerge as an instrumental part of the tumour-induced angiogenesis and vascular permeability modus operandi in GBM.

Inhibitory member of the apoptosis-stimulating protein of p53 is overexpressed in bladder cancer and correlated to its progression

Several lines of direct evidence show that inhibitory member of the apoptosis-stimulating protein of p53 (iASPP) has an important function in cancer progression. However, its expression pattern and relationship with clinical pathologic characteristics in bladder cancer (BC) have not been completely elucidated. In this study, firstly, samples from 3 patients with invasive BC were detected by liquid chromatography tandem mass spectrometry to confirm overexpression of iASPP in BC, then samples from patients with noninvasive and invasive BC were detected by real-time polymerase chain reaction, Western blot, and tissue microarry immunohistochemistry. The relationship between iASPP expression and various clinicopathological features was investigated. The results showed m-RNA and protein of iASPP were overexpressed in BC and the rate of iASPP-positive cells was positively correlated with Union for International Cancer Control-Tumor, Node, Metastases stage, histologic grade, lymph node metastasis and poor overall survive. The data demonstrate that iASPP is overexpressed in BC and promotes the malignancy of BC. iASPP maybe serve as a potential therapeutic target for BC.

High expression of VEGF and PI3K in glioma stem cells provides new criteria for the grading of gliomas

Glioma is a type of tumor derived from glial cells, which is associated with a high level of incidence and mortality. At present, the generation of a fast and efficient method to evaluate the malignancy grade of glioma is required. Cancer stem cells (CSCs) are currently attracting attention in oncological studies; therefore, the present study aimed to investigate novel biomarkers of glioma CSCs, in order to provide new criteria for the grading of glioma. The mRNA expression levels of CD133, (sex determining region Y)-box 2, nestin, vascular endothelial growth factor (VEGF) and phosphoinositide-3-kinase (PI3K) were detected in 15 human samples of high-malignancy glioma and 12 human samples of low-malignancy glioma in vitro. The mRNA expression levels of VEGF and PI3K were higher in the high-malignancy group, as compared with in the low-malignancy group. In conclusion, the mRNA expression levels of VEGF and PI3K in glioma CSCs may be considered a novel criteria for the grading of glioma.

Application of inhibitors of differentiation 2 and 3 for evaluation of chemotherapy efficacy in liver cancer

AIM: To explore the influence of surgery alone and in combination with postoperative adjuvant chemotherapy on tumor markers, inhibitor of differentiation 2 (ID2), ID3 and survival time in patients with liver cancer, analyze the influence of ID2 and ID3 on the invasion and metastasis of liver cancer, and explore the feasibility of detection of ID2 and ID3 expression in evaluating efficacy of postoperative adjuvant chemotherapy.

METHODS: This was a 1:1 matched case-control study. ELISA was used to detect the levels of tumor markers, ID2 and ID3 in the serum of patients. Western blot was used to detect the protein expression levels of ID2 and ID3 in tumor tissues and adjacent tissues. Transwell assay was used to detect the invasion and metastasis of liver cancer cells. The correlation between the content of AFP and the expression levels of ID2 and ID3 was statistically analyzed.

RESULTS: The tumor markers CEA, CA50, AFP, and CA242 as well as ID2 and ID3 in the serum decreased significantly and the survival time was longer in patients receiving surgery with postoperative adjuvant chemotherapy when compared with patients receiving surgery alone (P < 0.05). The protein expression levels of ID2 and ID3 were decreased in the adjacent normal tissues compared with the liver cancer tissues (P < 0.05). Transwell analysis indicated that ID2 and ID3 knockdown inhibited the invasion and metastasis ability of HepG2 cells while overexpression of ID2 and ID3 promoted the invasion and metastasis of HepG2 cells (P < 0.05). There was a positive correlation between the content of AFP and the expression levels of ID2 and ID3 (r_ID2 = 0.881, r_ID3 = 0.928, P < 0.05).

CONCLUSION: ID2 and ID3 have similar effects to liver tumor markers, and the increased expression of ID2 and ID3 indicates greater invasion and metastasis ability of HepG2 cells and shorter survival time in patients with liver cancer. ID2 and ID3 expression might be used for clinical evaluation of efficacy of postoperative adjuvant chemotherapy.