Background: Glioma represents the most common malignant brain tumor. Outcomes of surgical resection are often unsatisfactory due to low sensitivity or resolution of imaging methods. Moreover, the use of traditional chemotherapeutics, such as doxorubicin (DOX), is limited due to their low blood–brain barrier (BBB) permeability. Recently, the development of nanotechnology could overcome these obstacles. Materials and methods: Hydrophobic superparamagnetic iron oxide nanoparticles (SPIO NPs) were prepared with the use of thermal decomposition method. They were coated with 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene glycol)-2000] (DSPE-PEG 2000) and DOX using a thin-film hydration method followed by loading of indocyanine green (ICG) into the phospholipid layers. Details regarding the characteristics of NPs were determined. The in vitro biocompatibility and antitumor efficacy were established with the use of MTT assay. In vivo fluorescence and magnetic resonance (MR) imaging were used to evaluate BBB penetration and accumulation of NPs at the tumor site. Antitumor efficacy was evaluated using measures of tumor size, median survival times, body weights, and H&E staining. Results: The multifunctional NPs generated had an average diameter of 22.9 nm, a zeta potential of -38.19 mV, and were capable of providing a sustained release of DOX. In vitro experiments demonstrated that the SPIO@DSPE-PEG/DOX/ICG NPs effectively enhanced cellular uptake of DOX as compared with that of free DOX. In vivo fluorescence and MR imaging revealed that the NPs not only effectively crossed the BBB but selectively accumulated at the tumor site. Meanwhile, among all groups studied, C6 glioma-bearing rats treated with the NPs exhibited the maximal degree of therapeutic efficacy, including smallest tumor volume, lowest body weight loss, and longest survival times, with no obvious side effects. Conclusion: These results suggest that the SPIO@DSPE-PEG/DOX/ICG NPs can not only function as a nanoprobe for MR and fluorescence bimodal imaging, but also as a vehicle to deliver chemotherapeutic drugs to the tumor site, to achieve the theranostic treatment of glioma.

Background/Aims: MiR-30a-5p, a member of the microRNA-30 family (miR-30), is known to function as a tumor suppressor in several different cancers. However, the expression levels, biological function, and underlying mechanisms of miR-30a-5p in renal cell carcinoma (RCC) remain unclear. Glucose-regulated protein78 (GRP78) is a common cancer biomarker and promotes the growth and survival of cancer cells. The expression of GRP78 has been reported to be modulated by miR-30a in neurons. In this study, the expression profile of miR-30a-5p in clear cell renal cell carcinoma (ccRCC) and its effect on ccRCC through regulating GRP78 expression was investigated. Methods: MiR-30a-5p expression was analyzed using bioinformatic software on open microarray datasets from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO), and confirmed by quantitative RT-PCR (qRT-PCR) in ccRCC cell lines. Cell proliferation was investigated using CCK-8 and cell count assays. Western blotting, immunohistochemistry, luciferase reporter assays, and flow cytometry were employed to investigate the mechanisms of the effect of miR-30a-5p on ccRCC Results: MiR-30a-5p was down-regulated in ccRCC and related to the clinicopathological factors and prognosis of ccRCC. MiR-30a-5p was found to both suppress the growth of ccRCC cells and promote apoptosis of ccRCC cells in vitro. GRP78 was the direct target gene of miR-30a-5p, and the GRP78 expression was inversely correlated with the expression of miR-30a-5p in vivo and in vitro. The functional studies of GRP78 overexpression or knockdown demonstrated that GRP78 promoted proliferation and anti-apoptosis of ccRCC cells, and the oncogenic activity of GRP78 resulting in by miR-30a-5p overexpression. Conclusion: MiR-30a-5p is a bona fide negative regulator of GRP78 expression, and the anti-tumor activity of miR-30a-5p in ccRCC is due at least in part to down-regulating GRP78 expression and modulating the unfolded protein response (UPR) pathway. Thus, miR-30-GRP78 interaction provides a novel therapeutic candidate target in ccRCC treatment.

Background/Aims: Glioblastoma multiforme (GBM) is the most malignant primary brain tumor with a poor prognosis. Combination treatment of autophagy inducer and autophagy inhibitor may be a feasible solution to improve the therapeutic effects. However, the correlation between them is unclear. The purpose of this study was to investigate the effect of autophagy inhibition at different stages on cytotoxicity of autophagy inducers in glioblastoma cells. Methods: Autophagy inhibition at early stage was achieved by 3-methyladenine (3-MA) or Beclin 1 shRNA. Autophagy inhibition at late stage was achieved by chloroquine (CQ) or Rab7 shRNA. Cell viability was assessed by MTT assay. Autophagy was measured using transmission electron microscopy and western blot. Apoptosis was measured using western blot and flow-cytometry. Results: Inhibition of early steps of autophagy by 3-MA or Beclin 1 knockdown decreased the toxic effect of arsenic trioxide (ATO) in GBM cell lines. In contrast, blockade of autophagy flux at late stage by CQ or Rab7 knockdown enhanced the cytotoxicity of ATO, and caused accumulation of degradative autophagic vacuoles and robust apoptosis. Moreover, depletion of Beclin 1 abolished the synergistic effect of ATO and CQ by reducing autophagy and apoptosis. Combination of CQ with other autophagy inducers also induced synergistic apoptotic cell death. Conclusion: These results suggest that inhibition of late process of autophagy, not initial step, increases the cytotoxic effect of autophagy inducers via autophagy and apoptosis, which may contribute to GBM chemotherapy.

Glioblastoma is the most common and aggressive primary brain tumor in adults. New drug design and development is still a major challenge for glioma treatment. Increasing evidence has shown that nitazoxanide, an antiprotozoal drug, has a novel antitumor role in various tumors and exhibits multiple molecular functions, especially autophagic regulation. However, whether nitazoxanide-associated autophagy has an antineoplastic effect in glioma remains unclear. Here, we aimed to explore the underlying molecular mechanism of nitazoxanide in glioblastoma. Our results showed that nitazoxanide suppressed cell growth and induced cell cycle arrest in glioblastoma by upregulating ING1 expression with a favorable toxicity profile. Nitazoxanide inhibited autophagy through blockage of late-stage lysosome acidification, resulting in decreased cleavage of ING1. A combination with chloroquine or Torin1 enhanced or impaired the chemotherapeutic effect of nitazoxanide in glioblastoma cells. Taken together, these findings indicate that nitazoxanide as an autophagy inhibitor induces cell cycle arrest in glioblastoma via upregulated ING1 due to increased transcription and decreased post-translational degradation by late-stage autophagic inhibition.