Cisplatin downregulates BCL2L12, a novel apoptosis-related gene, in glioblastoma cells

A Novel Approach for Glioblastoma Treatment by Combining Apoptosis Inducers (TMZ, MTX, and Cytarabine) with E.V.A. (Eltanexor, Venetoclax, and A1210477) Inhibiting XPO1, Bcl-2, and Mcl-1

Adjuvant treatment for Glioblastoma Grade 4 with Temozolomide (TMZ) inevitably fails due to therapeutic resistance, necessitating new approaches. Apoptosis induction in GB cells is inefficient, due to an excess of anti-apoptotic XPO1/Bcl-2-family proteins. We assessed TMZ, Methotrexate (MTX), and Cytarabine (Ara-C) (apoptosis inducers) combined with XPO1/Bcl-2/Mcl-1-inhibitors (apoptosis rescue) in GB cell lines and primary GB stem-like cells (GSCs). Using CellTiter-Glo® and Caspase-3 activity assays, we generated dose-response curves and analyzed the gene and protein regulation of anti-apoptotic proteins via PCR and Western blots. Optimal drug combinations were examined for their impact on the cell cycle and apoptosis induction via FACS analysis, paralleled by the assessment of potential toxicity in healthy mouse brain slices. Ara-C and MTX proved to be 150- to 10,000-fold more potent in inducing apoptosis than TMZ. In response to inhibitors Eltanexor (XPO1; E), Venetoclax (Bcl-2; V), and A1210477 (Mcl-1; A), genes encoding for the corresponding proteins were upregulated in a compensatory manner. TMZ, MTX, and Ara-C combined with E, V, and A evidenced highly lethal effects when combined. As no significant cell death induction in mouse brain slices was observed, we conclude that this drug combination is effective in vitro and expected to have low side effects in vivo.

Biological evaluation of complexes of cyclopentadienyl M(CO)3+ (M = Re, 99mTc) with high blood-brain barrier penetration potential as brain cancer agents

To address the major medical need for effective chemotherapeutics/diagnostics for brain cancer, in this work three cyclopentadienyl M(CO)₃⁺ (M = Re, ^99mTc) complexes, which cross the blood-brain barrier (BBB) in high % and are designed to mimic the anticancer agent 2-phenylbenzothiazole, are in vitro and in vivo evaluated for anticancer action. The study includes cytotoxicity and uptake studies in cancer and healthy neuronal cell lines, mechanistic investigation of potential anticancer pathways, and biodistribution studies in mice bearing glioblastoma xenografts. The stable Re complexes exhibit selective uptake and significant antiproliferative effect, particularly against U-251 MG glioblastoma cells, with no significant toxicity in healthy neurons, demonstrating the suitability of this type of complexes to serve as selective therapeutic/imaging agents for brain cancer. Furthermore, they result in the generation of elevated Reactive Oxygen Species (ROS) levels, and lead to significant G2/M arrest followed by apoptosis. Biodistribution studies in U-251 MG xenograft bearing mice with the radioactive ^99mTc complex that exhibits the highest BBB penetration, show retention at the tumor-site offering a diagnostic prospect and, in addition, indicating the capability of the Re analogue to accumulate at the tumor site for therapeutic action. Overall, the complexes demonstrate significant anticancer properties that, combined with their high BBB penetration potential, render them strong candidates for further evaluation as brain cancer agents.

A novel μ-oxo-diruthenium(III,III)-ibuprofen-(4-aminopyridine) chloride derived from the diruthenium(II,III)-ibuprofen paddlewheel metallodrug shows anticancer properties

Diruthenium(II,III) metal-metal multiply bonded paddlewheel complexes bearing non-steroidal anti-inflammatory drugs are promising anticancer metallodrugs. The [Ru₂(Ibp)₄Cl] (Ibp, ibuprofenate anion from HIbp ibuprofen drug), free or encapsulated, shows anticancer activity against glioblastoma (in vitro, in vivo), and against human breast and prostate cancer cells. Herein we report the interaction of [Ru₂(Ibp)₄Cl] and of [Ru₂(Ac)₄(H₂O)₂]PF₆ (Ac, acetate) with the 4-aminopyridine (4Apy) drug. The N-ligand was capable of cleaving the paddlewheel unit with oxidation of Ru₂(II,III) to Ru₂(III,III)O μ-oxo core in the ibuprofen complex while the acetate complex underwent axial substitution of water by 4Apy. Carefully designed synthetic and chromatographic methods succeeded in giving the novel [Ru₂O(Ibp)₂(4Apy)₆]Cl₂ metallodrug, the first diruthenium(III,III) μ-oxo having chloride as counterion. Characterization was performed by elemental analysis, mass spectrometry, thermogravimetric analysis, electronic absorption and vibrational spectroscopies, molar conductivity and cyclic voltammetry. Kinetic studies for the μ-oxo complex (in 50:50 v/v ethanol:water) suggested an aquation/complexation equilibrium in consecutive step reactions with the exchange of the two 4Apy trans to the μ-oxo bridge by water (aquation) and the back coordination of 4Apy in excess of the N-ligand (complexation). Trypan blue assays for the novel compound showed time- and dose- dependent antiproliferative effects (at 5-50 μmol L^-1) and cytotoxicity (> 20 μmol L^-1), and MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide) assays gave IC₅₀ value of 7.6 ± 1.5 μmol L^-1 (at 48 h, 1-20 μmol L^-1) against U87MG human glioblastoma cells (aggressive brain glioma cancer) pointing the metallodrug as potential candidate for novel therapies in gliomas.

Co-Encapsulation of Fisetin and Cisplatin into Liposomes for Glioma Therapy: From Formulation to Cell Evaluation

(1) Background: Glioblastoma (GBM) is the most frequent cerebral tumor. It almost always relapses and there is no validated treatment for second-line GBM. We proposed the coencapsulation of fisetin and cisplatin into liposomes, aiming to (i) obtain a synergistic effect by combining the anti-angiogenic effect of fisetin with the cytotoxic effect of cisplatin, and (ii) administrate fisetin, highly insoluble in water. The design of a liposomal formulation able to encapsulate, retain and deliver both drugs appeared a challenge. (2) Methods: Liposomes with increasing ratios of cholesterol/DOPC were prepared and characterized in term of size, PDI and stability. The incorporation of fisetin was explored using DSC. The antiangiogneic and cytotoxic activities of the selected formulation were assayed in vitro. (3) Results: We successfully developed an optimized liposomal formulation incorporating both drugs, composed by DOPC/cholesterol/DODA-GLY-PEG2000 at a molar ratio of 75.3/20.8/3.9, with a diameter of 173 ± 8 nm (PDI = 0.12 ± 0.01) and a fisetin and cisplatin drug loading of 1.7 ± 0.3% and 0.8 ± 0.1%, respectively, with a relative stability over time. The maximum incorporation of fisetin into the bilayer was determined at 3.2% w/w. Then, the antiangiogenic activity of fisetin was maintained after encapsulation. The formulation showed an additive effect of cisplatin and fisetin on GBM cells; (4) Conclusions: The developed co-loaded formulation was able to retain the activity of fisetin, was effective against GBM cells and is promising for further in vivo experimentations.

In vivo Engineering of Chromosome 19 q-arm by Employing the CRISPR/AsCpf1 and ddAsCpf1 Systems in Human Malignant Gliomas (Hypothesis)

Deletions of the q13.3 region of chromosome 19 have been found commonly in all three main kinds of diffuse human malignant gliomas, powerfully demonstrating the existence of tumor suppressor genes in this region. Consistent with the previous studies, the most common deletion interval has been mapped to a roughly 4 Mb region of 19q13.3 between the APOC2 and HRC genes, between genetic markers D19S219 and D19S246. EML2 is a tumor suppressor gene that is located on 19q13.32 and is considerably methylated in high-grade gliomas. Notably, MIR330 gene that is situated within the non-coding intronic region of EML2 is also detected as an oncosuppressor-miR in a variety of cancers including gliomas. Additionally, glioma oncoprotein Bcl2L12 which is located on 19q13.33 is significantly overexpressed in glioblastoma multiform and has a pivotal role in cancer evolution and resistance to apoptosis. Other genes such as MIR519D and NOP53 are also discovered as tumor suppressor genes in gliomas which are located on 19q13.3 and 19q13.4, respectively. Therefore, we hypothesize that a CRISPR/AsCpf1-based genome engineering strategy might be utilized to attach these deleted sizeable chromosomal portions of genes coding tumor suppressors as vital parts of the chromosome 19 q-arm with the purpose of treatment of this chromosomal abnormality in gliomas. Also, we can concurrently employ the CRISPR-ddAsCpf1 strategy for the precise suppression of Bcl2L12 oncogene in glioma.

Disentangling the therapeutic tactics in GBM: From bench to bedside and beyond

Glioblastoma multiforme (GBM) is one of the most common and malignant form of adult brain tumor with a high mortality rate and dismal prognosis. The present standard treatment comprising surgical resection followed by radiation and chemotherapy using temozolomide can broaden patient's survival to some extent. However, the advantages are not palliative due to the development of resistance to the drug and tumor recurrence following the multimodal treatment approaches due to both intra- and intertumoral heterogeneity of GBM. One of the major contributors to temozolomide resistance is O⁶ -methylguanine-DNA methyltransferase. Furthermore, deficiency of mismatch repair, base excision repair, and cytoprotective autophagy adds to temozolomide obstruction. Rising proof additionally showed that a small population of cells displaying certain stem cell markers, known as glioma stem cells, adds on to the resistance and tumor progression. Collectively, these findings necessitate the discovery of novel therapeutic avenues for treating glioblastoma. As of late, after understanding the pathophysiology and biology of GBM, some novel therapeutic discoveries, such as drug repurposing, targeted molecules, immunotherapies, antimitotic therapies, and microRNAs, have been developed as new potential treatments for glioblastoma. To help illustrate, "what are the mechanisms of resistance to temozolomide" and "what kind of alternative therapeutics can be suggested" with this fatal disease, a detailed history of these has been discussed in this review article, all with a hope to develop an effective treatment strategy for GBM.

Molecular mechanisms of cell death induced in glioblastoma by experimental and antineoplastic drugs: New and old drugs induce apoptosis in glioblastoma

Glioblastoma multiforme (GBM) is one of the most aggressive astrocytic tumors; it is resistant to most chemotherapeutic agents currently available and is associated with a poor patient survival. Thus, the development of new anticancer compounds is urgently required. Herein, we studied the molecular mechanisms of cell death induced by the experimental drugs resveratrol and MG132 or the antineoplastic drugs cisplatin and etoposide on a human GBM cell line (D54) and on primary cultured mouse astrocytes (PCMAs). Caspases, Bcl-2, inhibitors of apoptosis proteins (IAP) family members, and p53 were identified as potential molecular targets for these drugs. All drugs had a cytotoxic effect on D54 cells and PCMAs, with a similar inhibitory concentration (IC₅₀) after 24 h. However, MG132 and cisplatin were more effective to induce apoptosis and autophagy than resveratrol and etoposide. Cell death by apoptosis involved the activation of caspases-3/7, -8, and -9, increased lysosomal permeability, LC3 lipidation, poly-(ADP-ribose) polymerase (PARP)-1 fragmentation, and a differential expression of genes related with apoptosis and autophagy like Mcl-1, Survivin, Noxa, LC3, and Beclin. In addition, apoptosis activation was partially dependent on p53 activation. Since experimental and antineoplastic drugs yielded similar results, further work is required to justify their use in clinical protocols.

Celastrus orbiculatus extracts induce apoptosis in mTOR-overexpressed human hepatocellular carcinoma HepG2 cells

Background

Celastrus orbiculatus (Celastraceae) are used as traditional Chinese medicine to treat inflammation and cancer. This study aims to evaluate the effect of Celastrus orbiculatus extract (COE) on the apoptosis in human hepatic carcinoma HepG2 cells with mTOR overexpression.

Methods

The stable expression of mTOR in HepG2 cells (HepG2/mTOR⁺) were established by lipofectin transfection of GV238-mTOR recombinant plasmids and further antibiotic selection. Human hepatic carcinoma HepG2/mTOR⁺ cells were treated with different concentrations (20, 40, 80, 160, and 320 μg/mL) of COE for 24 h. The cell proliferation upon COE treatment was detected by MTT. Apoptosis was measured by Flow Cytometry. The activity of mTOR signaling pathway was detected by Western Blotting.

Results

COE significantly inhibited the proliferation of HepG2/mTOR⁺ cells. The expression levels of Bax and Caspase-3 protein were increased in the HepG2/mTOR⁺ cells in a dose-dependent manner. The proteins expression of Bcl2, Bcl-2 L12, mTOR, phospho-mTOR, 4EBP1, phospho-4EBP1, P70S6k, and phospho-P70S6k in HepG2/mTOR⁺ cells were reduced in dose-dependent manners. Furthermore, COE and mTOR inhibitor rapamycin (RAPA) synergistically induced apoptosis in HepG2/mTOR⁺ cells by regulating apoptosis-related proteins and inhibiting mTOR signaling pathways.

Conclusion

COE could inhibit the proliferation of HepG2/mTOR⁺ cells, and induce the cell apoptosis. The mechanisms may be related to the regulation of the expression of Bcl-2, Bcl-2 L12, and mTOR signaling pathways. These data suggest that COE may be a potential treatment for human hepatocellular carcinoma.

Effect of microRNA-128 on cisplatin resistance of glioma SHG-44 cells by targeting JAG1

This current study intends to investigate the effect of microRNA-128 (miR-128) on cisplatin (DDP) resistance in glioma SHG-44 cells. SHG-44/DDP cells were transfected with miR-128 antisense oligonucleotide (ASO) and assigned into blank, resistance, NC, anti-miR-128, miR-128 mimic, si-JAG1, and anti-miR-128 + si-JAG1 groups. qRT-PCR and Western blotting were employed for determining expression of miR-128, JAG1, Bax and Bcl-2. MTT assay, Giemsa staining, and flow cytometry were applied to detect DDP resistance, cellular morphology, and cell cycle, respectively. JAG1 is targeted and negatively regulated by miR-128. In in vitro experiments, compared with the blank group, the rest groups exhibited declined miR-28 and Bax expression, lowered cell inhibition rate and apoptosis rate, but elevated JAG1 and Bcl-2 expression with cells arrested in the S phase. Compared with the resistance group, the anti-miR-128 group showed decreasedBax expression along with a lowered cell inhibition rate and apoptosis rate, but increased JAG1 and Bcl-2 expression with reduced cells arrested in the S phase; while the miR-128 mimic group showed an opposite trend; the si-JAG1 group showed decreased Bcl-2 expression and reduced cells in the S phase. In in vivo experiments, compared with the resistance group, the tumor growth rate, tumor volume, and weight as well as JAG1 expression accelerated in the anti-miR-128 group; whereas the miR-128 mimic and si-JAG1 groups exhibited an opposite trend. Our findings demonstrated that miR-128 ASO transfection might down-regulate the expression of miR-128 in SHG-44/DDP and up-regulate the DDP resistance in SHG-44/DDP cells, providing a potential treatment target for glioma.

Non-aggregated protamine-coated poly(lactide-co-glycolide) nanoparticles of cisplatin crossed blood-brain barrier, enhanced drug delivery and improved therapeutic index in glioblastoma cells: in vitro studies

BACKGROUND AND OBJECTIVES

Non-aggregated protamine impregnated poly(lactide-co-glycolide) nanoparticles of cisplatin (Pt-PLGA NPs) were synthesized to augment brain delivery.

METHODS AND RESULTS

The mean particle size of Pt-PLGA NPs and PLGA NPs were observed to be 173.2 ± 7.9 nm and 140 ± 10.2 nm, respectively. The Pt-PLGA NPs significantly (p < 0.05, one-way analysis of variance; ANOVA) delivered higher amount (172.41 ± 15.04 μg) of cisplatin in comparison to 110.48 ± 4.71 μg by PLGA NPs and 20.83 ± 1.65 μg by cisplatin solution across in vitro bovine brain microvessel endothelial cells. Cisplatin bearing Pt-PLGA NPs was found to be highly cytotoxic to U87 glioblastoma cells with an IC50 of 2.1 μM as compared (one-way ANOVA, p < 0.05) to PLGA NPs (3.9 μM) and cisplatin alone (13.33 μM). Impregnation with Pt enhanced the uptake of PLGA NPs in U87 glioblastoma cells as compared to PLGA NPs by following endocytosis mechanism.

CONCLUSION

Cisplatin-loaded Pt-PLGA NPs compel preclinical tumour regression study to further improve its utility against glioblastoma.