Reduced Graphene Oxides Modulate the Expression of Cell Receptors and Voltage-Dependent Ion Channel Genes of Glioblastoma Multiforme

circ-1584 selectively promotes the antitumor activity of the oncolytic virus M1 on pancreatic cancer

Pancreatic cancer is among the most challenging tumors to treat, and due to its immune tolerance characteristics, existing immunotherapy methods are not effective in alleviating the disease. Oncolytic virus therapy, a potential new strategy for treating pancreatic cancer, also faces the limitation of being ineffective when used alone. Elucidating the key host endogenous circular RNAs (circRNAs) involved in M1 virus-mediated killing of pancreatic ductal adenocarcinoma (PDAC) cells may help overcome this limitation. Here, we report that the oncolytic virus M1, a nonpathogenic alphavirus, exhibits different cell viability-inhibitory effects on different pancreatic cancer cells in the clinical stage. Through high-throughput circRNA sequencing, we found that circRNA expression varies among these cells. Further gain-of-function and loss-of-function experiments have shown that circ-1584 can selectively enhance the anti-pancreatic cancer effects of the M1 virus in vitro and in vivo. Additionally, circ-1584 may negatively regulate miR-578 to modulate the anti-pancreatic cancer effects of the M1 virus. Our findings lay the foundation for using circRNA as an adjuvant to enhance the M1 virus efficacy against pancreatic cancer.

Radiosensitizing properties of dual-functionalized carbon nanostructures loaded with temozolomide

In the present study, temozolomide (TMZ), a drug used for the treatment of anaplastic astrocytoma and glioblastoma multiforme (GBM), was incorporated into multiwalled carbon nanotubes (MWCNTs) and a MWCNTs-graphene (MWCNTs-G) hybrid compound, covalently functionalized with polyethylene glycol (PEG) 6000 and folic acid (FA), with an aim to prepare nanocarriers with the potential to prolong the drug circulation time, cross the blood-brain-tumor barrier (BBTB), and provide targeted and controlled drug release in the brain tumor cells. Cytotoxicity and effects on cell membrane integrity of the blank and TMZ-loaded dual-functionalized carbon nanostructures (CNs) were evaluated in vitro on a GBM cell line (U87MG), as well as their radiosensitizing properties after exposure of the pre-treated GBM cells to gamma radiation with a standard clinical dose for patients with GBM. All prepared formulations underwent biopharmaceutical and physicochemical characterization, including the formulations exposed to irradiation under the same conditions. For physicochemical characterization of the formulations, different techniques were used by which successful functionalization of the CNs and TMZ loading were confirmed and visualized; no significant changes in the structure of the CNs and TMZ after irradiation were observed. With single and dual functionalization, formulations with relatively high TMZ loading efficiency and drug content were prepared. They exhibited homogeneous particle size distributions and mean particle sizes and surface charges suitable for crossing the BBTB and targeting brain cancer cells. A biphasic drug release profile was observed for all functionalized TMZ-loaded formulations in simulated in vivo conditions, with a sustained release pointing to the potential for controlled release of TMZ in brain tumor cells. The formulations of the hybrid CN MWCNTs-G compared to the corresponding MWCNTs were characterized by a similar or slightly higher TMZ content, larger particle size, similar surface charge, and slightly faster TMZ release, which can be attributed to the planar structure of graphene that promotes TMZ binding to the surface on a larger scale. For the irradiated CNs, lower values for particle size, more positive values for surface charge, and accelerated TMZ release were observed, which could be explained by changes in the physicochemical characteristics of the prepared formulations upon irradiation. Significant concentration-dependent toxicity was observed for blank dual-functionalized CNs, being higher for MWCNTs-G-PEG6000-FA compared to MWCNTs-PEG6000-FA at the same formulation concentrations. With incorporation of TMZ into the functionalized CNs, the cell viability additionally decreased, maintaining the trend for higher cytotoxicity of the hybrid CN. Additional decrease in the viability of cells was observed when GBM cells pre-treated with the corresponding CNs were exposed to irradiation, which could be ascribed to changes in size, surface charge, and release kinetics of TMZ and to irradiation-induced changes in the microenvironment and cell membranes that promote uptake of a larger volume of carriers in the GBM cells. The higher cytotoxicity observed in the hybrid carrier formulations could most likely be attributed to the length of the hybrid carrier and the higher proportion of planar surface, which promotes more intense contact with the cells and rupture of cell membranes. Overall, the findings demonstrate the radiosensitizing properties of not only TMZ but also of CNs and point to a clinical benefit from combined treatment with carbon nanocarriers of TMZ and radiotherapy in GBM.

Gamma radiation assisted green synthesis of hesperidin-reduced graphene oxide nanocomposite targeted JNK/SMAD4/MMP2 signaling pathway

In this study, a novel method for the fabrication of hesperidin/reduced graphene oxide nanocomposite (RGOH) with the assistance of gamma rays is reported. The different RGOHs were obtained by varying hesperidin concentrations (25, 50, 100, and 200 wt.%) in graphene oxide (GO) solution. Hesperidin concentrations (25, 50, 100, and 200 wt.%) in graphene oxide (GO) were varied to produce the various RGOHs. Upon irradiation with 80 kGy from γ-Ray, the successful reduction of GO occurred in the presence of hesperidin. The reduction process was confirmed by different characterization techniques such as FTIR, XRD, HRTEM, and Raman Spectroscopy. A cytotoxicity study using the MTT method was performed to evaluate the cytotoxic-anticancer effects of arbitrary RGOH on Wi38, CaCo2, and HepG2 cell lines. The assessment of RGOH's anti-inflammatory activity, including the monitoring of IL-1B and IL-6 activities as well as NF-kB gene expression was done. In addition, the anti-invasive and antimetastatic properties of RGOH, ICAM, and VCAM were assessed. Additionally, the expression of the MMP2-9 gene was quantified. The assessment of apoptotic activity was conducted by the detection of gene expressions related to BCl2 and P53. The documentation of the JNK/SMAD4/MMP2 signaling pathway was ultimately accomplished. The findings of our study indicate that RGOH therapy has significant inhibitory effects on the JNK/SMAD4/MMP2 pathway. This suggests that it could be a potential therapeutic option for cancer.

Neurodiagnostic and neurotherapeutic potential of graphene nanomaterials

Graphene has emerged as a highly promising nanomaterial for a variety of advanced technologies, including batteries, energy, electronics, and biotechnologies. Its recent contribution to neurotechnology is particularly noteworthy because its superior conductivity, chemical resilience, biocompatibility, thermal stability, and scalable nature make it well-suited for measuring brain activity and plasticity in health and disease. Graphene-mediated compounds are microfabricated in two central methods: chemical processes with natural graphite and chemical vapor deposition of graphene in a film form. They are widely used as biosensors and bioelectronics for neurodiagnostic and neurotherapeutic purposes in several brain disorders, such as Parkinson's disease, stroke, glioma, epilepsy, tinnitus, and Alzheimer's disease. This review provides an overview of studies that have demonstrated the technical advances of graphene nanomaterials in neuroscientific and clinical applications. We also discuss current limitations and future demands in relation to the clinical application of graphene, highlighting its potential technological and clinical significance for treating brain disorders. Our review underscores the potential of graphene nanomaterials as powerful tools for advancing the understanding of the brain and developing new therapeutic strategies.

Theranostic Applications of 2D Graphene-Based Materials for Solid Tumors Treatment

Solid tumors are a leading cause of cancer-related deaths globally, being characterized by rapid tumor growth and local and distant metastases. The failures encountered in cancer treatment are mainly related to the complicated biology of the tumor microenvironment. Nanoparticles-based (NPs) approaches have shown the potential to overcome the limitations caused by the pathophysiological features of solid cancers, enabling the development of multifunctional systems for cancer diagnosis and therapy and allowing effective inhibition of tumor growth. Among the different classes of NPs, 2D graphene-based nanomaterials (GBNs), due to their outstanding chemical and physical properties, easy surface multi-functionalization, near-infrared (NIR) light absorption and tunable biocompatibility, represent ideal nanoplatforms for the development of theranostic tools for the treatment of solid tumors. Here, we reviewed the most recent advances related to the synthesis of nano-systems based on graphene, graphene oxide (GO), reduced graphene oxide (rGO), and graphene quantum dots (GQDs), for the development of theranostic NPs to be used for photoacoustic imaging-guided photothermal-chemotherapy, photothermal (PTT) and photodynamic therapy (PDT), applied to solid tumors destruction. The advantages in using these nano-systems are here discussed for each class of GBNs, taking into consideration the different chemical properties and possibility of multi-functionalization, as well as biodistribution and toxicity aspects that represent a key challenge for their translation into clinical use.

Functional Graphene for Peritumoral Brain Microenvironment Modulation Therapy in Glioblastoma

Peritumoral brain invasion is the main target to cure glioblastoma. Chemoradiotherapy and targeted therapies fail to combat peritumoral relapse. Brain inaccessibility and tumor heterogeneity explain this failure, combined with overlooking the peritumor microenvironment. Reduce graphene oxide (rGO) provides a unique opportunity to modulate the local brain microenvironment. Multimodal graphene impacts are reported on glioblastoma cells in vitro but fail when translated in vivo because of low diffusion. This issue is solved by developing a new rGO formulation involving ultramixing during the functionalization with polyethyleneimine (PEI) leading to the formation of highly water-stable rGO-PEI. Wide mice brain diffusion and biocompatibility are demonstrated. Using an invasive GL261 model, an anti-invasive effect is observed. A major unexpected modification of the peritumoral area is also observed with the neutralization of gliosis. In vitro, mechanistic investigations are performed using primary astrocytes and cytokine array. The result suggests that direct contact of rGO-PEI_UT neutralizes astrogliosis, decreasing several proinflammatory cytokines that would explain a bystander tumor anti-invasive effect. rGO also significantly downregulates several proinvasive/protumoral cytokines at the tumor cell level. The results open the way to a new microenvironment anti-invasive nanotherapy using a new graphene nanomaterial that is optimized for in vivo brain delivery.

Potential Role of Carbon Nanomaterials in the Treatment of Malignant Brain Gliomas

Malignant gliomas are the most common primary brain tumors in adults up to an extent of 78% of all primary malignant brain tumors. However, total surgical resection is almost unachievable due to the considerable infiltrative ability of glial cells. The efficacy of current multimodal therapeutic strategies is, furthermore, limited by the lack of specific therapies against malignant cells, and, therefore, the prognosis of these in patients is still very unfavorable. The limitations of conventional therapies, which may result from inefficient delivery of the therapeutic or contrast agent to brain tumors, are major reasons for this unsolved clinical problem. The major problem in brain drug delivery is the presence of the blood-brain barrier, which limits the delivery of many chemotherapeutic agents. Nanoparticles, thanks to their chemical configuration, are able to go through the blood-brain barrier carrying drugs or genes targeted against gliomas. Carbon nanomaterials show distinct properties including electronic properties, a penetrating capability on the cell membrane, high drug-loading and pH-dependent therapeutic unloading capacities, thermal properties, a large surface area, and easy modification with molecules, which render them as suitable candidates for deliver drugs. In this review, we will focus on the potential effectiveness of the use of carbon nanomaterials in the treatment of malignant gliomas and discuss the current progress of in vitro and in vivo researches of carbon nanomaterials-based drug delivery to brain.

Reduced Graphene Oxide Modulates the FAK-Dependent Signaling Pathway in Glioblastoma Multiforme Cells In Vitro

Aggressive invasiveness is a common feature of malignant gliomas, despite their high level of tumor heterogeneity and possible diverse cell origins. Therefore, it is important to explore new therapeutic methods. In this study, we evaluated and compared the effects of graphene (GN) and reduced graphene oxides (rGOs) on a highly invasive and neoplastic cell line, U87. The surface functional groups of the GN and rGO flakes were characterized by X-ray photoelectron spectroscopy. The antitumor activity of these flakes was obtained by using the neutral red assay and their anti-migratory activity was determined using the wound healing assay. Further, we investigated the mRNA and protein expression levels of important cell adhesion molecules involved in migration and invasiveness. The rGO flakes, particularly rGO/ATS and rGO/TUD, were found highly toxic. The migration potential of both U87 and Hs5 cells decreased, especially after rGO/TUD treatment. A post-treatment decrease in mobility and FAK expression was observed in U87 cells treated with rGO/ATS and rGO/TUD flakes. The rGO/TUD treatment also reduced β-catenin expression in U87 cells. Our results suggest that rGO flakes reduce the migration and invasiveness of U87 tumor cells and can, thus, be used as potential antitumor agents.

The Role of Graphene Oxide Nanocarriers in Treating Gliomas

Gliomas are the most common primary malignant tumors of the central nervous system, and their conventional treatment involves maximal safe surgical resection combined with radiotherapy and temozolomide chemotherapy; however, this treatment does not meet the requirements of patients in terms of survival and quality of life. Graphene oxide (GO) has excellent physical and chemical properties and plays an important role in the treatment of gliomas mainly through four applications, viz. direct killing, drug delivery, immunotherapy, and phototherapy. This article reviews research on GO nanocarriers in the treatment of gliomas in recent years and also highlights new ideas for the treatment of these tumors.