Cancer-cell-specific Self-Reporting Photosensitizer for Precise Identification and Ablation of Cancer Cells.

Cancer-cell-specific fluorescent photosensitizers (PSs) are highly desired molecular tools for cancer ablation with minimal damage to normal cells. However, such PSs that can achieve cancer specification and ablation and a self-reporting manner concurrently are rarely reported and still an extremely challenging task. Herein, we have proposed a feasible strategy and conceived a series of fluorescent PSs based on simple chemical structures for identifying and killing cancer cells as well as monitoring the photodynamic therapy (PDT) process by visualizing the change of subcellular localization. All of the constructed cationic molecules could stain mitochondria in cancer cells, identify cancer cells specifically, and monitor cancer cell viability. Among these, IVP-Br has the strongest ability to produce ROS, which serves as a potent PS for specific recognition and killing of cancer cells. IVP-Br could translocate from mitochondria to the nucleolus during PDT, self-reporting the entire therapeutic process. Mechanism study confirms that IVP-Br with light irradiation causes cancer cell ablation via inducing cell cycle arrest, cell apoptosis, and autophagy. The efficient ablation of tumor through PDT induced by IVP-Br has been confirmed in the 3D tumor spheroid chip. Particularly, IVP-Br could discriminate cancer cells from white blood cells (WBCs), exhibiting great potential to identify circulating tumor cells (CTCs).

Charge-elimination strategy for constructing RNA-selective fluorescent probe undisturbed by mitochondria.

Visualizing Ribonucleic acid (RNA) dynamics inside live cells is crucially important for the research of life science. However, almost all of the reported RNA probes target RNA with cationic groups, and mitochondria with high negative transmembrane potential may bring significant interferences. As a result, precise visualization of RNA in living cells is still a greatly challenging task. To overcome this problem, in this work, we proposed a novel charge-elimination strategy to construct a fluorescent probe (H-SMBT) specific for RNA undisturbed by mitochondria in live cells. Probe H-SMBT was designed to target the negative groove of RNA with a cationic group, and an additional hydroxyl group was modified to overcome the interference from mitochondria. H-SMBT will change from cationic structure to a charge-eliminated state in mitochondria with weak alkalic environment and detach from mitochondria, and therefore, it can exclusively stain RNA in live cells. Using M-SMBT with a methoxy group as a comparative molecule, we confirmed that the phenol group in H-SMBT played a decisive role to achieve the RNA specificity. Furthermore, H-SMBT can fast stain live cells in 5 min with excellent RNA selectivity. The probe can also monitor cellular damage processes, and successfully be applied to live zebrafish imaging due to the good tissue permeability. This work provides a new design strategy for constructing RNA-selective fluorescent probes avoiding the interference from mitochondria, and the designed RNA probe can be widely used for RNA-related life science research.

LATS2 inhibits cell proliferation and metastasis through the Hippo signaling pathway in glioma.

As a core kinase in the Hippo pathway, large tumor suppressor kinase 2 (LATS2) regulates cell proliferation, migration and invasion through numerous signaling pathways. However, its functions on cell proliferation, migration and invasion in glioma have yet to be elucidated. The present study revealed that LATS2 was downregulated in glioma tissues and cells, as determined by reverse transcription­quantitative polymerase chain reaction and immunohistochemistry. In addition, Cell Counting Kit­8, scratch wound healing and Transwell assays revealed that overexpression of LATS2 in U­372 MG cells inhibited cell proliferation, migration and invasion. Furthermore, western blot analysis indicated that the expression levels of phosphorylated (p)­yes­associated protein and p­tafazzin were increased in cells with LATS2 overexpression. These results indicated that LATS2 is a potential tumor suppressor, and downregulation of LATS2 in glioma may contribute to cancer progression.

Long Noncoding RNA LINC00958 Accelerates Gliomagenesis Through Regulating miR-203/CDK2.

Increasing evidence has indicated that long noncoding RNAs (lncRNAs) play crucial roles in various biological processes, including glioma. However, the underlying mechanism of lncRNAs in gliomagenesis is still ambiguous. In this study, we aim to investigate the role of long intergenic noncoding RNA 00958 (LINC00958) in the tumorigenesis of glioma. Results revealed that LINC00958 was significantly upregulated in glioma tissues and cell lines compared with that of adjacent normal brain tissues and normal human astrocytes. Moreover, the ectopic overexpression of LINC00958 was correlated with poor prognosis of glioma patients. Loss-of-function experiments indicated that LINC00958 knockdown suppressed glioma cell proliferation, invasion, and induced cycle arrest at G0/G1 phase in vitro, and inhibited tumor growth in vivo. Bioinformatics programs and luciferase reporter assay revealed that miR-203 shared complementary binding sites with both 3'-untranslated region of LINC00958 and CDK2. In summary, our study concludes that LINC00958 acts as an oncogenic gene in the gliomagenesis through miR-203-CDK2 regulation, providing a novel insight into glioma tumorigenesis.

Cytoplasmic polyadenylation element-binding protein 4 is highly expressed in human glioma.

Cytoplasmic polyadenylation element-binding protein 4 (CPEB4) is a highly conserved, sequence-specific RNA-binding protein that recruits translational repression or cytoplasmic polyadenylation machinery to target mRNAs. Recent studies have shown that CPEBs are expressed in somatic tissues and have essential functions supporting tumor growth, vascularization, and invasion. Overexpression of CPEB4 has been reported in pancreatic ductal adenocarcinoma and is associated with poor prognoses. However, whether CPEB4 plays a role in the tumorigenesis of gliomas is unknown. Here, we analyzed the expression of CPEB4 in gliomas. The expression profiles of CPEB4 mRNA and protein in nine normal brain tissues and 63 gliomas were detected using immunohistochemistry, real-time PCR, and western blotting. CPEB4-positive expression was significantly correlated with the pathological grade of glioma; abundant expression was observed in high-grade gliomas, whereas little or no expression was observed in normal astrocytes. Immunohistochemistry staining indicated that CPEB4 was mainly localized in the cytoplasm. In addition, CPEB4 was more highly expressed in U87 glioma cells than in U251 cells. CPEB4 expression significantly correlated with the grade in clinical gliomas. This study suggested that CPEB4 might play a role in the pathogenesis of glioma.

Eukaryotic translation initiation factor 3, subunit C is overexpressed and promotes cell proliferation in human glioma U-87 MG cells.

Disrupted protein translation is prevalent in tumours. Eukaryotic translation initiation factors (eIFs) were found to play an important role in various tumours. However, the involvement of eIFs in glioma remains to be elucidated. The present study explored the expression and the role of eIF 3, subunit C (eIF3c) in human glioma. The expression of eIF3c in glioma tissues was evaluated by immunohistochemistry. The impact of eIF3c inhibition on U-87 MG was explored in vitro and in vivo by lentivirus-mediated siRNA targeting eIF3c. The results revealed that overexpression of eIF3c was present in glioma tissues. Knockdown of eIF3c significantly impaired cell proliferation and colony formation, further induced cell cycle arrest and apoptosis in the U-87 MG cell line. Furthermore, tumoursphere formation in the U-87 MG glioma xenograft model was blocked by eIF3c knockdown. The involvement of eIF3c in the tumorigenesis of glioma was confirmed, suggesting eIF3c may be a promising therapy target in human glioma.

Differential effects of miR-34c-3p and miR-34c-5p on the proliferation, apoptosis and invasion of glioma cells.

Glioblastoma is the most malignant and common intrinsic brain tumor, but the molecular mechanism of glioma pathophysiology is poorly understood. Recent data have shown that microRNAs regulate the expression of several genes associated with human cancer. In the present study, the function of miR-34c in glioma cells was analyzed. It was demonstrated that miR-34c-3p and miR-34c-5p were downregulated in gliomas, by performing qPCR on tumor tissues from glioma patients and glioma cell lines, compared with normal brain tissues and a normal glial cell line. Furthermore, the miR-34c expression was found to be inversely correlated with glioma WHO grades. Overexpression of miR-34c-3p inhibited U251 and U87 cell proliferation; however, miR-34c-5p only had an effect on U251 cells. Transfection with miR-34c-3p or miR-34c-5p in U251 cells and with miR-34c-3p in U87 cells produced S-phase arrest with G0/G1 reduction and induced cell apoptosis, but no significant changes were observed with miR-34c-5p transfection in U87 cells, normal or negative control groups. However, significant inhibition of glioma cell invasion was observed following transfection with miR-34c-3p and miR-34c-5p. Moreover, it was identified that miR-34c-3p overexpression reduced the expression of Notch pathway members, but miR-34c-5p overexpression did not. Therefore, these results suggest differential tumor suppressor roles for miR-34c-3p and miR-34c-5p and provide new insights into the role of miR-34c in glioma, which includes tumor-suppressing effects on proliferation, apoptosis and invasiveness.

Rho-associated coiled kinase inhibitor Y-27632 promotes neuronal-like differentiation of adult human adipose tissue-derived stem cells.

BACKGROUND: Y-27632 is a specific inhibitor of Rho-associated coiled kinase (ROCK) and has been shown to promote the survival and induce the differentiation of a variety of cells types. However, the effects of Y-27632 on adult human adipose tissue-derived stem cells (ADSCs) are unclear. This study aimed to investigate the effects of Y-27632 on the neuronal-like differentiation of ADSCs. METHODS: ADSCs were isolated from women undergoing plastic surgery and cultured. ADSCs were treated with different doses of Y-27632 and observed morphological changes under microscope. The expression of nestin, neuron specific enolase (NSE) and microtubule-associated protein-2 (MAP-2) in ADSCs treated with Y-27632 was detected by immunocytochemistry and Western blotting analysis. RESULTS: Y-27632 had the potency to induce neuronal-like differentiation in ADSCs in a dose-dependent manner. Moreover, the differentiation induced by Y-27632 was recovered upon drug withdraw. ADSCs treated with Y-27632 expressed neuronal markers such as NSE, MAP-2 and nestin while untreated ADSCs did not express these markers. CONCLUSION: Selective ROCK inhibitor Y-27632 could potentiate the neuronal-like differentiation of ADSCs, suggesting that Y-27632 could be utilized to induce the differentiation of ADSCs to neurons and facilitate the clinical application of ADSCs in tissue engineering.

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.

[Treatment of cutaneous vertebral medullary angiomatosis].

OBJECTIVE: Cutaneous vertebral medullary angiomatosis, also known as Cobb's syndrome, is a part of spinal arteriovenous metameric syndromes (SAMs), is derived from the vascular malformation triad of skin, bone, and spinal cord involvement. It is poorly managed with current treatment modalities. We reviewed the treatment of Cobb's syndrome series and summarized the experiences. METHODS: A total of 61 cases of Cobb's syndrome with spinal cord dysfunction were treated at our department from February 2003 to December 2007. The treatment followed the same strategy: First step-investigating the pathogenic mechanisms by symptom onset, MRI, angiography and the response to initial treatment. Second step-treating the problematic parts of the lesions with embolization alone, surgery alone or combination of both. Forty-eight cases were embolized, 3 cases treated with surgery and 10 cases treated with a combination of both. Nidus involving pathogenic mechanism for spinal cord were eliminated, completely and nearly disappeared in 36 cases and partially in 25 cases. All patients were followed up regularly. RESULTS: Among these 61 cases, the pathogenic mechanisms were identified as hemorrhage, mass effect, ischemia and venous hypertensive myelopathy. Two or more mechanisms could coexist in the same patient. More than 1-year's spinal cord function follow-up showed: excellent in 9 cases, good in 26, fair in 23 and worse in 3. CONCLUSION: Not all lesions of Cobb's syndrome can be or should be cured anatomically. Pathogenic mechanism should be analyzed carefully and the treatment should focus on the special cord-affecting targets. Long-term improvement or stabilization may be achieved.