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Viruses Feb 2020Currently, no rabies virus-specific antiviral drugs are available. Ranpirnase has strong antitumor and antiviral properties associated with its ribonuclease activity....
Currently, no rabies virus-specific antiviral drugs are available. Ranpirnase has strong antitumor and antiviral properties associated with its ribonuclease activity. TMR-001, a proprietary bulk drug substance solution of ranpirnase, was evaluated against rabies virus in three cell types: mouse neuroblastoma, BSR (baby hamster kidney cells), and bat primary fibroblast cells. When TMR-001 was added to cell monolayers 24 h preinfection, rabies virus release was inhibited for all cell types at three time points postinfection. TMR-001 treatment simultaneous with infection and 24 h postinfection effectively inhibited rabies virus release in the supernatant and cell-to-cell spread with 50% inhibitory concentrations of 0.2-2 nM and 20-600 nM, respectively. TMR-001 was administered at 0.1 mg/kg via intraperitoneal, intramuscular, or intravenous routes to Syrian hamsters beginning 24 h before a lethal rabies virus challenge and continuing once per day for up to 10 days. TMR-001 at this dose, formulation, and route of delivery did not prevent rabies virus transit from the periphery to the central nervous system in this model ( = 32). Further aspects of local controlled delivery of other active formulations or dose concentrations of TMR-001 or ribonuclease analogues should be investigated for this class of drugs as a rabies antiviral therapeutic.
Topics: Animals; Antiviral Agents; Cell Line; Cells, Cultured; Chiroptera; Cricetinae; Female; Fibroblasts; Mesocricetus; Mice; Rabies; Rabies virus; Ribonucleases; Virus Release; Virus Replication
PubMed: 32033253
DOI: 10.3390/v12020177 -
Bioengineered Apr 2022CD45RA is a specific marker for leukemia stem cell (LSC) sub-populations in acute myeloid leukemia (AML). Ranpirnase (Rap), an amphibian RNase, has been extensively...
CD45RA is a specific marker for leukemia stem cell (LSC) sub-populations in acute myeloid leukemia (AML). Ranpirnase (Rap), an amphibian RNase, has been extensively investigated in preclinical and clinical studies for its antitumor activity. Rap could be administered repeatedly to patients without inducing an immune response. Reversible renal toxicity has been reported to be dose-limiting. In this study, we generated a novel immunotoxin targeting LSCs: Hm3A4-Rap, which was composed of Rap and Hm3A4, a human-mouse chimeric antibody against CD45RA. This immunotoxin was generated recombinantly by fusing Rap to Hm3A4 at the Fc terminus and then produced by stably transfecting CHO cells. The immunotoxin was purified using Ni-NTA and then evaluated using RT-PCR, SDS-PAGE, antibody titer assays, competitive inhibition assays, and internalization assays. In addition, the purity, molecular integrity, and affinity to the CD45RA antigen were determined. studies demonstrated that Hm3A4-Rap could efficiently kill target cells. studies demonstrated that Hm3A4-Rap had potent anti-leukemia activity, with dosed mice showing a significant increase in survival time compared to control mice (P < 0.01). In summary, our immunotoxin had excellent biological activity suggesting its potential therapeutic value for treating AML patients. Additional preclinical and clinical studies are needed to develop this immunotoxin as a treatment option for patients with leukemia.
Topics: Animals; Cell Lineage; Cricetinae; Cricetulus; Humans; Immunotoxins; Leukemia, Myeloid, Acute; Mice; Ribonucleases; Xenograft Model Antitumor Assays
PubMed: 35322728
DOI: 10.1080/21655979.2022.2054159 -
Pathogens (Basel, Switzerland) Dec 2022Adenovirus ocular infections are common ocular viral infections seen worldwide, for which there is no approved antiviral therapy available. Ranpirnase is a novel...
Adenovirus ocular infections are common ocular viral infections seen worldwide, for which there is no approved antiviral therapy available. Ranpirnase is a novel ribonuclease which preferentially degrades tRNA resulting in an inhibition of protein synthesis. The study goal was to determine the anti-adenoviral activity of topical formulations of ranpirnase (OKG-0301) on adenoviral replication in the Ad5/NZW rabbit ocular replication model. NZW rabbits were inoculated in both eyes with human adenovirus type 5 (HAdV5) after corneal scarification. A day later, topical therapy was initiated in both eyes with 0.03% OKG-0301, 0.003% OKG-0301, saline or 0.5% cidofovir. Eyes were cultured to determine HAdV5 eye titers over 2 weeks. OKG-0301 (0.03% and 0.003%) and 0.5% cidofovir decreased viral titers compared to saline. Furthermore, both OKG-0301 formulations and 0.5% cidofovir shortened the duration of the HAdV5 infection compared to saline. Both 0.03% OKG-0301 and 0.003% OKG-0301 demonstrated increased antiviral activity compared to saline in the Ad5/NZW rabbit ocular replication model. The antiviral activity of the OKG-0301 groups was similar to that of the positive antiviral control, 0.5% cidofovir. Ranpirnase (OKG-0301) may be a potential candidate for a topical antiviral for adenoviral eye infections. Further clinical development is warranted.
PubMed: 36558819
DOI: 10.3390/pathogens11121485 -
International Journal of Molecular... Jun 2022The majority of transcribed RNAs do not codify for proteins, nevertheless they display crucial regulatory functions by affecting the cellular protein expression profile.... (Review)
Review
The majority of transcribed RNAs do not codify for proteins, nevertheless they display crucial regulatory functions by affecting the cellular protein expression profile. MicroRNAs (miRNAs) and transfer RNA-derived small RNAs (tsRNAs) are effectors of interfering mechanisms, so that their biogenesis is a tightly regulated process. Onconase (ONC) is an amphibian ribonuclease known for cytotoxicity against tumors and antiviral activity. Additionally, ONC administration in patients resulted in clinical effectiveness and in a well-tolerated feature, at least for lung carcinoma and malignant mesothelioma. Moreover, the ONC therapeutic effects are actually potentiated by cotreatment with many conventional antitumor drugs. This review not only aims to describe the ONC activity occurring either in different tumors or in viral infections but also to analyze the molecular mechanisms underlying ONC pleiotropic and cellular-specific effects. In cancer, data suggest that ONC affects malignant phenotypes by generating tRNA fragments and miRNAs able to downregulate oncogenes expression and upregulate tumor-suppressor proteins. In cells infected by viruses, ONC hampers viral spread by digesting the primer tRNAs necessary for viral DNA replication. In this scenario, new therapeutic tools might be developed by exploiting the action of ONC-elicited RNA derivatives.
Topics: Antineoplastic Agents; Cell Line, Tumor; DNA Replication; DNA, Viral; Humans; MicroRNAs; Neoplasms; RNA, Transfer; Ribonucleases; Virus Diseases; Virus Replication
PubMed: 35742999
DOI: 10.3390/ijms23126556 -
International Journal of Molecular... Jan 2022Onconase (ONC) is an amphibian secretory ribonuclease displaying cytostatic and cytotoxic activities against many mammalian tumors, including melanoma. ONC principally...
Onconase (ONC) is an amphibian secretory ribonuclease displaying cytostatic and cytotoxic activities against many mammalian tumors, including melanoma. ONC principally damages tRNA species, but also other non-coding RNAs, although its precise targets are not known. We investigated the ONC ability to modulate the expression of 16 onco-suppressor microRNAs (miRNAs) in the A375 BRAF-mutated melanoma cell line. RT-PCR and immunoblots were used to measure the expression levels of miRNAs and their regulated proteins, respectively. In silico study was carried out to verify the relations between miRNAs and their mRNA targets. A375 cell transfection with miR-20a-3p and miR-34a-5p mimics or inhibitors was performed. The onco-suppressors miR-20a-3p, miR-29a-3p and miR-34a-5p were highly expressed in 48-h ONC-treated A375 cells. The cytostatic effect of ONC in A375 cells was mechanistically explained by the sharp inhibition of cyclins D1 and A2 expression level, as well as by downregulation of retinoblastoma protein and cyclin-dependent-kinase-2 activities. Remarkably, the expression of kinases ERK1/2 and Akt, as well as of the hypoxia inducible factor-1α, was inhibited by ONC. All these proteins control pro-survival pathways. Finally, many crucial proteins involved in migration, invasion and metastatic potential were downregulated by ONC. Results obtained from transfection of miR-20a-3p and miR-34a-5p inhibitors in the presence of ONC show that these miRNAs may participate in the antitumor effects of ONC in the A375 cell line. In conclusion, we identified many intracellular downregulated proteins involved in melanoma cell proliferation, metabolism and progression. All mRNAs coding these proteins may be targets of miR-20a-3p, miR-29a-3p and/or miR-34a-5p, which are in turn upregulated by ONC. Data suggest that several known ONC anti-proliferative and anti-metastatic activities in A375 melanoma cells might depend on the upregulation of onco-suppressor miRNAs. Notably, miRNAs stability depends on the upstream regulation by long-non-coding-RNAs or circular-RNAs that can, in turn, be damaged by ONC ribonucleolytic activity.
Topics: Cell Line, Tumor; Cell Proliferation; Cell Survival; Computer Simulation; Down-Regulation; Drug Screening Assays, Antitumor; Gene Expression Regulation, Neoplastic; Gene Regulatory Networks; Humans; Melanoma; MicroRNAs; Ribonucleases; Up-Regulation
PubMed: 35163570
DOI: 10.3390/ijms23031647 -
Journal of Pharmacological and... 2023The aim of the recent study was to collect data on the genotype characteristics of the Hungarian self-bred Pannon minipigs by adapting a standardized infarct model...
The aim of the recent study was to collect data on the genotype characteristics of the Hungarian self-bred Pannon minipigs by adapting a standardized infarct model procedure. Closed chest AMI was induced by balloon occlusion for 90 min in the left anterior descendent coronary artery (LAD) in 24 adult intact female minipigs followed by reperfusion. To assess the left ventricular (LV) function, serial cardiac magnetic resonance imaging (cMRI) was performed prior to the experimental procedure, on day 3 post-AMI (72 ± 12 h), and at 1 month follow-up (Day 30 ± 2 days). Compared to baseline cMRI scans the end-diastolic volume (EDV) was increased on days 3 and 30 On day 3 the left ventricular ejection fraction (LVEF) decreased significantly but there was no statistical difference between the baseline and day 30 measurements. Cardiac output, stroke volume, and end-systolic volume significantly were increased compared to baseline on day 30 A high percentage (54%) of malignant arrhythmias occurred during the AMI procedure, with a 25% mortality rate. The compensatory capacity of the Pannon minipig heart is excellent therefore the use of different cardiac parameters and invasive measurements is advisable in chronic pharmacological experiments to complement cMRI data.
Topics: Swine; Animals; Female; Swine, Miniature; Stroke Volume; Myocardial Infarction; Ventricular Function, Left; Ribonucleases
PubMed: 37598810
DOI: 10.1016/j.vascn.2023.107469 -
International Journal of Molecular... Nov 2019Melanoma is a lethal tumor because of its severe metastatic potential, and serine/threonine-protein kinase B-raf inhibitors (BRAFi) are used in patients harboring...
Melanoma is a lethal tumor because of its severe metastatic potential, and serine/threonine-protein kinase B-raf inhibitors (BRAFi) are used in patients harboring BRAF-mutation. Unfortunately, BRAFi induce resistance. Therefore, we tested the activity of onconase (ONC), a cytotoxic RNase variant, against BRAFi-resistant cells to re-establish the efficacy of the chemotherapy. To do so, an A375 dabrafenib-resistant (A375DR) melanoma cell subpopulation was selected and its behavior compared with that of parental (A375P) cells by crystal violet, 5-Bromo-2'-deoxyuridine incorporation, and cleaved poly(ADP-ribose) polymerase 1 (PARP1) western blot measurements. Then, nuclear p65 Nuclear Factor kappaB (NF-κB) and IκB kinases-α/β (IKK) phosphorylation levels were measured. Gelatin zymography was performed to evaluate metalloproteinase 2 (MMP2) activity. In addition, assays to measure migration, invasion and soft agar colony formation were performed to examine the tumor cell dissemination propensity. ONC affected the total viability and the proliferation rate of both A375P and A375DR cell subpopulations in a dose-dependent manner and also induced apoptotic cell death. Among its pleiotropic effects, ONC reduced nuclear p65 NF-κB amount and IKK phosphorylation level, as well as MMP2 activity in both cell subpopulations. ONC decreased cell colony formation, migration, and invasion capability. Notably, it induced apoptosis and inhibited colony formation and invasiveness more extensively in A375DR than in A375P cells. In conclusion, ONC successfully counteracts melanoma malignancy especially in BRAFi-resistant cells and could become a tool against melanoma recurrence.
Topics: Antineoplastic Agents; Apoptosis; Cell Line, Tumor; Cell Movement; Cell Proliferation; Cytotoxins; Drug Resistance, Neoplasm; Gene Expression Regulation, Neoplastic; Humans; I-kappa B Kinase; Imidazoles; Matrix Metalloproteinase 2; Melanoma; NF-kappa B; Neoplasm Invasiveness; Oximes; Protein Kinase Inhibitors; Proto-Oncogene Proteins B-raf; Ribonucleases; Signal Transduction; Stem Cells
PubMed: 31783660
DOI: 10.3390/ijms20235980