Isoginkgetin (Iso) is a natural bioflavonoid isolated from the leaves of
, this natural substance exhibits many healing properties, among which the antitumor effect stands out. Here we tested the ...effect of Iso on the growth of U87MG glioblastoma cells. Growth curves and MTT toxicity assays showed time and dose-dependent growth inhibition of U87MG after treatment with Iso (15/25 µM) for 1, 2, and 3 days. The cell growth block of U87MG was further investigated with the colony formation test, which showed that iso treatment for 24 h reduced colony formation. The present study also aimed to evaluate the effect of Iso on U87MG glioblastoma cell migration. The FACS analysis, on the other hand, showed that treatment with Iso 15 µM determines a blockage of the cell cycle in the S1 phase. Further investigation shows that Iso treatment of U87MG altered the protein pathways of homeostasis including autophagy and apoptosis. The present study demonstrated, for the first time, that Iso could represent an excellent adjuvant drug for the treatment of glioblastoma by simultaneously activating multiple mechanisms that control the growth and migration of neoplastic cells.
Glioblastoma, the most dangerous and aggressive type of CNS tumor, appears resistant to many chemotherapy drugs. In the patient-derived glioma cell lines NULU and ZAR, which exhibit drug-resistant ...phenotypes, we investigated the effect of combined AE (Aloe-emodin) and TMZ (temozolomide) and found a significant additive inhibitory effect on cell growth and a promising cytotoxic effect on both cell lines compared to treatment with single agents. We also examined the effect of combined AE and TMZ treatment on the drug-resistance protein MGMT. The results suggest that using AE combined with traditional drugs restores drug resistance in both primary resistant cell lines (NULU and ZAR). Furthermore, migration assays and scratch tests showed that the combined use of AE and TMZ can slow down the colony formation and migration of glioblastoma cells. These convincing results suggest that AE could be a natural adjuvant agent to potentiate the effects of traditional drugs (TMZ) and overcome drug resistance in glioblastoma cells.
In this study, we propose lactucopicrin (LCTP), a natural sesquiterpene lactone from Lactucavirosa, as a molecule able to control the growth of glioblastoma continuous cell line U87Mg. The IC50 of ...U87Mg against LCTP revealed a strong cytotoxic effect. Daily administration of LCTP showed a dose and time-dependent reduction of GBM cell growth and viability, also confirmed by inhibition of clonogenic potential and mobility of U87Mg cells. LCTP activated autophagy in U87Mg cells and decreased the phosphorylation of proliferative signals pAKT and pERK. LCTP also induced the cell cycle arrest in G2/M phase, confirmed by decrease of CDK2 protein and increase of p53 and p21. LCTP stimulated apoptosis as evidenced by reduction of procaspase 6 and the increase of the cleaved/full-length PARP ratio. The pre-treatment of U87Mg cells with ROS scavenger N-acetylcysteine (NAC), which reversed its cytotoxic effect, showed the involvement of LCTP in oxidative stress. Finally, LCTP strongly enhanced the sensitivity of U87Mg cells to canonical therapy Temozolomide (TMZ) and synergized with this drug. Altogether, the growth inhibition of U87Mg GBM cells induced by LCTP is the result of several synergic mechanisms, which makes LCTP a promising adjuvant therapy for this complex pathology.
Erythropoiesis-stimulating agents are first choice for treating anemia in low-risk MDS. This double-blind, placebo-controlled study assessed the efficacy and safety of epoetin-α in IPSS low- or ...intermediate-1 risk (i.e., low-risk) MDS patients with Hb ≤ 10.0 g/dL, with no or moderate RBC transfusion dependence (≤4 RBC units/8 weeks). Patients were randomized, 2:1, to receive epoetin-α 450 IU/kg/week or placebo for 24 weeks, followed by treatment extension in responders. The primary endpoint was erythroid response (ER) through Week 24. Dose adjustments were driven by weekly Hb-levels and included increases, and dose reductions/discontinuation if Hb > 12 g/dL. An independent Response Review Committee (RRC) blindly reviewed all responses, applying IWG-2006 criteria but also considering dose adjustments, drug interruptions and longer periods of observation.A total of 130 patients were randomized (85 to epoetin-α and 45 to placebo). The ER by IWG-2006 criteria was 31.8% for epoetin-α vs 4.4% for placebo (p < 0.001); after RRC review, the ER was 45.9 vs 4.4% (p < 0.001), respectively. Epoetin-α reduced RBC transfusions and increased the time-to-first-transfusion compared with placebo.Thus, epoetin-α significantly improved anemia outcomes in low-risk MDS. IWG-2006 criteria for ER may require amendments to better apply to clinical studies.
Abstract The molecular target of rapamycin (mTOR) is up-regulated in glioblastoma (GBM) and this is associated with the rate of cell growth, stem cell proliferation and disease relapse. Rapamycin is ...a powerful mTOR inhibitor and strong autophagy inducer. Previous studies analyzed the effects of rapamycin in GBM cell lines. However, to our knowledge, no experiment was carried out to evaluate the effects of rapamycin neither in primary cells derived from GBM patients nor in vivo in brain GBM xenograft. These data are critical to get a deeper insight into the effects of such adjuvant therapy in GBM patients. In the present study, various doses of rapamycin were tested in primary cell cultures from GBM patients. These effects were compared with that obtained by the same doses of rapamycin in GBM cell lines (U87Mg). The effects of rapamycin were also evaluated in vivo , in brain tumors developed from mouse xenografts. Rapamycin, starting at the dose of 10 nm inhibited cell growth both in U87Mg cell line and primary cell cultures derived from various GBM patients. When administered in vivo to brain xenografts in nude mice rapamycin almost doubled the survival time of mice and inhibited by more than 95% of tumor volume.
Recently, several studies focused on the genetics of gliomas. This allowed identifying several germline loci that contribute to individual risk for tumor development, as well as various somatic ...mutations that are key for disease classification. Unfortunately, none of the germline loci clearly confers increased risk per se. Contrariwise, somatic mutations identified within the glioma tissue define tumor genotype, thus representing valid diagnostic and prognostic markers. Thus, genetic features can be used in glioma classification and guided therapy. Such copious genomic variabilities are screened routinely in glioma diagnosis. In detail, Sanger sequencing or pyrosequencing, fluorescence in-situ hybridization, and microsatellite analyses were added to immunohistochemistry as diagnostic markers. Recently, Next Generation Sequencing was set-up as an all-in-one diagnostic tool aimed at detecting both DNA copy number variations and mutations in gliomas. This approach is widely used also to detect circulating tumor DNA within cerebrospinal fluid from patients affected by primary brain tumors. Such an approach is providing an alternative cost-effective strategy to genotype all gliomas, which allows avoiding surgical tissue collection and repeated tumor biopsies. This review summarizes available molecular features that represent solid tools for the genetic diagnosis of gliomas at present or in the next future.
Cynaropicrin has shown a wide range of pharmacological properties, such as antitumor action. Here, we showed the inhibitory effect of Cyn on human glioblastoma cell U-87 MG growth. According to the ...IC50 values, Cyn 4, 8 and 10 µM displayed a significant cytotoxicity, as confirmed by the cell count and MTT assay. Furthermore, Cyn completely abolished the ability of U-87 MG to form colonies and induced drastic morphological changes. Interestingly, pretreatment with ROS scavenger N-acetylcysteine 3 mM reversed the cytotoxicity induced by Cyn 25 µM and preserved the cells by morphological changes. Therefore, oxidative stress induction was evaluated at low 8- and high 25-µM concentrations in U-87 MG, as demonstrated by the quantitative and qualitative analysis of ROS. A prolonged increase in ROS generation under Cyn 25 µM exposure was followed by the loss of the mitochondrial membrane potential in treated U-87 MG cells. An acute treatment with Cyn 25 µM induced Cyt c release, as revealed by immunofluorescence staining and the activation of cell death pathways, apoptosis and autophagy. On the other hand, chronic treatment with Cyn 8 µM induced senescence, as revealed by the increase in SA-β-Gal activity. Moreover, at this concentration, Cyn led to ERK dephosphorylation accompanied by a relevant reduction of the NF-κB p65 subunit. Finally, the combined effect of TMZ and Cyn resulted in synergistic cytotoxicity, as evaluated by the Bliss additivity model. The strong cytotoxicity of Cyn was also confirmed on IDH1 mutant U-87 MG cells and patient-derived IDH wild-type glioblastoma cell lines NULU and ZAR. In conclusion, given the high toxicity at minimal concentrations, the high inhibition of tumor cell growth and synergy with the standard drug for glioblastoma TMZ, Cyn could be proposed as a potential adjuvant for the treatment of glioblastoma.
Temozolomide (TMZ) is the current first-line chemotherapy for treatment of glioblastoma multiforme (GBM). However, similar to other brain therapeutic compounds, access of TMZ to brain tumors is ...impaired by the blood–brain barrier (BBB) leading to poor response for GBM patients. To overcome this major hurdle, we have synthesized a set of TMZ-encapsulating nanomedicines made of four cationic liposome (CL) formulations with systematic changes in lipid composition and physical–chemical properties. The targeting nature of this nanomedicine is provided by the recruitment of proteins, with natural targeting capacity, in the biomolecular corona (BC) layer that forms around CLs after exposure to human plasma (HP). TMZ-loaded CL–BC complexes were thoroughly characterized by dynamic light scattering (DLS), electrophoretic light scattering (ELS), and nanoliquid chromatography tandem mass spectrometry (nano-LC MS/MS). BCs were found to be enriched of typical BC fingerprints (BCFs) (e.g., Apolipoproteins, Vitronectin, and vitamin K-dependent protein), which have a substantial capacity in binding to receptors that are overexpressed at the BBB (e.g., scavenger receptor class B, type I and low-density lipoprotein receptor). We found that the CL formulation exhibiting the highest levels of targeting BCFs had larger uptake in human umbilical vein endothelial cells (HUVECs) that are commonly used as an in vitro model of the BBB. This formulation could also deliver TMZ to the human glioblastoma U-87 MG cell line and thus substantially enhance their antitumor efficacy compared to corona free CLs. Thus, we propose that the BC-based nanomedicines may pave a more effective way for efficient treatment of GBM.
Ribosome inactivating proteins (RIPs) are specific N-β-glycosylases that are well-characterized in plants. Their enzymatic action is to damage ribosomes, thereby blocking protein translation. ...Recently, several research groups have been working on the screening for these toxins in edible plants to facilitate the use of RIPs as biotechnological tools and biopesticides and to overcome public prejudice. Here, four novel monomeric (type 1) RIPs have been isolated from the seeds of
L. var.
, which is commonly known as edible red mountain spinach. These enzymes, named hortensins 1, 2, 4, and 5, are able to release the β-fragment and, like many other RIPs, adenines from salmon sperm DNA, thus, acting as polynucleotide:adenosine glycosidases. Structurally, hortensins have a different molecular weight and are purified with different yields (hortensin 1, ~29.5 kDa, 0.28 mg per 100 g; hortensin 2, ~29 kDa, 0.29 mg per 100 g; hortensin 4, ~28.5 kDa, 0.71 mg per 100 g; and hortensin 5, ~30 kDa, 0.65 mg per 100 g); only hortensins 2 and 4 are glycosylated. Furthermore, the major isoforms (hortensins 4 and 5) are cytotoxic toward human continuous glioblastoma U87MG cell line. In addition, the morphological change in U87MG cells in the presence of these toxins is indicative of cell death triggered by the apoptotic pathway, as revealed by nuclear DNA fragmentation (TUNEL assay).
Here, we propose Ageritin, the prototype of the ribotoxin-like protein family, as an adjuvant treatment to control the growth of NULU and ZAR, two primary human glioblastoma cell lines, which exhibit ...a pharmacoresistance phenotype. Ageritin is able to inhibit NULU and ZAR growth with an IC50 of 0.53 ± 0.29 µM and 0.42 ± 0.49 µM, respectively. In this study, Ageritin treatment highlighted a macroscopic genotoxic response through the formation of micronuclei, which represents the morphological manifestation of genomic chaos induced by this toxin. DNA damage was not associated with either the deregulation of DNA repair enzymes (i.e., ATM and DNA-PK), as demonstrated by quantitative PCR, or reactive oxygen species. Indeed, the pretreatment of the most responsive cell line ZAR with the ROS scavenger N-acetylcysteine (NAC) did not follow the reverse cytotoxic effect of Ageritin, suggesting that this protein is not involved in cellular oxidative stress. Vice versa, Ageritin pretreatment strongly enhanced the sensitivity to temozolomide (TMZ) and inhibited MGMT protein expression, restoring the sensitivity to temozolomide. Overall, Ageritin could be considered as a possible innovative glioblastoma treatment, directly damaging DNA and downregulating the MGMT DNA repair protein. Finally, we verified the proteolysis susceptibility of Ageritin using an in vitro digestion system, and considered the future perspective use of this toxin as a bioconjugate in biomedicine.
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