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Molecules (Basel, Switzerland) Oct 2021Mosquito-borne viruses including dengue, Zika, and Chikungunya viruses, and parasites such as malaria and endanger health and economic security around the globe, and...
Mosquito-borne viruses including dengue, Zika, and Chikungunya viruses, and parasites such as malaria and endanger health and economic security around the globe, and emerging mosquito-borne pathogens have pandemic potential. However, the rapid spread of insecticide resistance threatens our ability to control mosquito vectors. Larvae of were screened with the Medicines for Malaria Venture Pandemic Response Box, an open-source compound library, using INVAPP, an invertebrate automated phenotyping platform suited to high-throughput chemical screening of larval motility. We identified rubitecan (a synthetic derivative of camptothecin) as a hit compound that reduced larval motility. Both rubitecan and camptothecin displayed concentration dependent reduction in larval motility with estimated EC of 25.5 ± 5.0 µM and 22.3 ± 5.4 µM, respectively. We extended our investigation to adult mosquitoes and found that camptothecin increased lethality when delivered in a blood meal to adults at 100 µM and 10 µM, and completely blocked egg laying when fed at 100 µM. Camptothecin and its derivatives are inhibitors of topoisomerase I, have known activity against several agricultural pests, and are also approved for the treatment of several cancers. Crucially, they can inhibit Zika virus replication in human cells, so there is potential for dual targeting of both the vector and an important arbovirus that it carries.
Topics: Aedes; Animals; Antiviral Agents; Camptothecin; Drug Discovery; Female; High-Throughput Screening Assays; Humans; Insecticide Resistance; Insecticides; Larva; Mosquito Vectors; Motor Activity; Pandemics; Topoisomerase I Inhibitors; Vector Borne Diseases; Virus Replication; Zika Virus
PubMed: 34684807
DOI: 10.3390/molecules26206226 -
Journal of Biomolecular Structure &... May 2021In December 2019, COVID-19 epidemic was described in Wuhan, China, and the infection has spread widely affecting hundreds of thousands. Herein, an effort was made to...
In December 2019, COVID-19 epidemic was described in Wuhan, China, and the infection has spread widely affecting hundreds of thousands. Herein, an effort was made to identify commercially available drugs in order to repurpose them against coronavirus by the means of structure-based virtual screening. In addition, ZINC15 library was used to identify novel leads against main proteases. Human TMPRSS2 3D structure was first generated using homology modeling approach. Our molecular docking study showed four potential inhibitors against Mpro enzyme, two available drugs (Talampicillin and Lurasidone) and two novel drug-like compounds (ZINC000000702323 and ZINC000012481889). Moreover, four promising inhibitors were identified against TMPRSS2; Rubitecan and Loprazolam drugs, and compounds ZINC000015988935 and ZINC000103558522. ADMET profile showed that the hits from our study are safe and drug-like compounds. Furthermore, molecular dynamic (MD) simulation and binding free energy calculation using the MM-PBSA method was performed to calculate the interaction energy of the top-ranked drugs.Communicated by Ramaswamy H. Sarma.
Topics: COVID-19; Cysteine Endopeptidases; Drug Repositioning; Humans; Molecular Docking Simulation; Peptide Hydrolases; Pharmaceutical Preparations; Protease Inhibitors; SARS-CoV-2; Viral Nonstructural Proteins
PubMed: 32306862
DOI: 10.1080/07391102.2020.1758791 -
Molecules (Basel, Switzerland) Feb 2014Advanced small cell lung cancer (SCLC) has a dismal prognosis. Modulation of the camptothecin topotecan, approved for second-line therapy, may improve response. Our...
Advanced small cell lung cancer (SCLC) has a dismal prognosis. Modulation of the camptothecin topotecan, approved for second-line therapy, may improve response. Our recent finding of synergistic enhancement of the cytotoxic activity of camptothecin (CPT) by cyclin-dependent kinase 4 inhibitors is extended here to a panel of camptothecin analogs comprising 10-hydroxy-CPT (HOCPT), topotecan (TPT; 9-[(dimethylamino)-methyl]-10-hydroxy-CPT), 9-amino-CPT (9AC), 9-nitrocamptothecin (rubitecan), SN38 (7-ethyl-10-hydroxycamptothecin) and 10-hydroxy-9-nitrocamptothecin (CPT109) in combination with PD0332991, CDK4I, roscovitine and olomoucine. SCLC cell lines employed are chemoresistant NCI-H417 and DMS153 and the chemosensitive SCLC26A line established at our institution. The CPT analogs exhibiting highest cytotoxicity towards the three SCLC lines tested were SN38 and 9AC, followed by rubitecan, HOCPT, TPT and CPT109. NCI-H417 and DMS153 revealed an approximately 25-fold and 7-fold higher resistance compared to the chemosensitive SCLC26A cell line. Whereas the CDK4/6 inhibitor PD0332991 proved less effective to chemosensitize SCLC cells to CPT analogs, the CDK inhibitors CDK4I, roscovitine and olomoucine gave comparable chemosensitization effects in combination with 9AC, SN38, rubitecan and to a lesser extent with TPT and CPT109, not directly related with topoisomerase mRNA expression. In conclusion, small chemical modifications of the parent CPT structure result in differing cytotoxicities and chemomodulatory effects in combination with CDKIs of the resulting analogs.
Topics: Antineoplastic Agents; Camptothecin; Cell Line, Tumor; Cyclin-Dependent Kinases; Drug Synergism; Enzyme Inhibitors; Humans; Irinotecan; Small Cell Lung Carcinoma; Topotecan
PubMed: 24549232
DOI: 10.3390/molecules19022077 -
Cancer Biology & Therapy Jul 2013Chordoma is a rare, slow growing malignant tumor arising from remnants of the fetal notochord. Surgery is the first choice for chordoma treatment, followed by...
Chordoma is a rare, slow growing malignant tumor arising from remnants of the fetal notochord. Surgery is the first choice for chordoma treatment, followed by radiotherapy, although postoperative complications remain significant. Recurrence of the disease occurs frequently due to the anatomy of the tumor location and violation of the tumor margins at the initial surgery. Currently, there are no effective drugs available for patients with chordoma. Due to the rarity of the disease, there is limited opportunity to test agents in clinical trials and no concerted effort to develop agents for chordoma in the pharmaceutical industry. To rapidly and efficiently identify small molecules that inhibit chordoma cell growth, we screened the NCGC Pharmaceutical Collection (NPC) containing approximately 2800 clinically approved and investigational drugs at 15 different concentrations in chordoma cell lines, U-CH1 and U-CH2. We identified a group of drugs including bortezomib, 17-AAG, digitoxin, staurosporine, digoxin, rubitecan, and trimetrexate that inhibited chordoma cell growth, with potencies from 10 to 370 nM in U-CH1 cells, but less potently in U-CH2 cells. Most of these drugs also induced caspase 3/7 activity with a similar rank order as the cytotoxic effect on U-CH1 cells. Cantharidin, digoxin, digitoxin, staurosporine, and bortezomib showed similar inhibitory effect on cell lines and 3 primary chordoma cell cultures. The combination treatment of bortezomib with topoisomerase I and II inhibitors increased the therapeutic potency in U-CH2 and patient-derived primary cultures. Our results provide information useful for repurposing currently approved drugs for chordoma and potential approach of combination therapy.
Topics: Antineoplastic Agents; Cell Line, Tumor; Cell Proliferation; Chordoma; Drug Screening Assays, Antitumor; Humans; Small Molecule Libraries
PubMed: 23792643
DOI: 10.4161/cbt.24596 -
PloS One 2011Hepatocellular carcinoma (HCC) is the third most common cause of cancer related mortality worldwide. 9-Nitrocamptothecin (9NC) is a potent topoisomerase-I inhibitor with...
BACKGROUND
Hepatocellular carcinoma (HCC) is the third most common cause of cancer related mortality worldwide. 9-Nitrocamptothecin (9NC) is a potent topoisomerase-I inhibitor with strong anticancer effect. To increase the solubility and stability, we synthesized a novel 9NC loaded liposomes (9NC-LP) via incorporating 9NC into liposomes. In the present study, we determined the effects of 9NC and 9NC-LP on in vitro and in vivo, and the underlying mechanisms.
METHODOLOGY/PRINCIPAL FINDINGS
We first analyzed the characteristics of 9NC-LP. Then we compared the effects of 9NC and 9NC-LP on the proliferation and apoptosis of HepG2, Bel-7402, Hep3B and L02 cells in vitro. We also investigated their anticancer properties in nude mice bearing HCC xenograft in vivo. 9NC-LP has a uniform size (around 190 nm) and zeta potential (∼-11 mV), and exhibited a steady sustained-release pattern profile in vitro. Both 9NC and 9NC-LP could cause cell cycle arrest and apoptosis in a dose-dependent and p53-dependent manner. However, this effect was not ubiquitous in all cell lines. Exposure to 9NC-LP led to increased expression of p53, p21, p27, Bax, caspase-3, caspase-8, caspase-9 and apoptosis-inducing factor, mitochondrion-associated 1 and decreased expression of Bcl-2, cyclin E, cyclin A, Cdk2 and cyclin D1. Furthermore, 9NC-LP exhibited a more potent antiproliferative effect and less side effects in vivo. Western blot analysis of the xenograft tumors in nude mice showed similar changes in protein expression in vivo.
CONCLUSIONS/SIGNIFICANCE
In conclusion, 9NC and 9NC-LP can inhibit HCC growth via cell cycle arrest and induction of apoptosis. 9NC-LP has a more potent anti-tumor effect and fewer side effects in vivo, which means it is a promising reagent for cancer therapy via intravenous administration.
Topics: Animals; Antineoplastic Agents; Apoptosis; Camptothecin; Carcinoma, Hepatocellular; Cell Cycle; Cell Line, Tumor; Cell Proliferation; Drug Stability; Female; Gene Expression Regulation, Neoplastic; Humans; Liposomes; Liver Neoplasms; Mice; Solubility; Ultrasonics; Water; Xenograft Model Antitumor Assays
PubMed: 21695227
DOI: 10.1371/journal.pone.0021064 -
International Journal of Nanomedicine Aug 2010The purpose in this study was to investigate poly(ethylene glycol)-modified poly (d,l-lactide-co-glycolide) nanoparticles (PLGA-PEG-NPs) loading 9-nitrocamptothecin...
The purpose in this study was to investigate poly(ethylene glycol)-modified poly (d,l-lactide-co-glycolide) nanoparticles (PLGA-PEG-NPs) loading 9-nitrocamptothecin (9-NC) as a potent anticancer drug. 9-NC is an analog of the natural plant alkaloid camptothecin that has shown high antitumor activity and is currently in the end stage of clinical trial. Unfortunately, at physiological pH, these potent agents undergo a rapid and reversible hydrolysis with the loss of antitumor activity. Previous researchers have shown that the encapsulation of this drug in PLGA nanoparticles could increase its stability and release profile. In this research we investigated PLGA-PEG nanoparticles and their effect on in vitro characteristics of this labile drug. 9-NC-PLGA-PEG nanoparticles with particle size within the range of 148.5 ± 30 nm were prepared by a nanoprecipitation method. The influence of four different independent variables (amount of polymer, percent of emulsifier, internal phase volume, and external phase volume) on nanoparticle drug-loading was studied. Differential scanning calorimetry and X-ray diffractometry were also evaluated for physical characterizing. The results of optimized formulation showed a narrow size distribution, suitable zeta potential (+1.84), and a drug loading of more than 45%. The in vitro drug release from PLGA-PEG NPs showed a sustained release pattern of up to 120 hours and comparing with PLGA-NPs had a significant decrease in initial burst effect. These experimental results indicate that PLGA-PEG-NPs (versus PLGA-NPs) have a better physicochemical characterization and can be developed as a drug carrier in order to treat different malignancies.
Topics: Antineoplastic Agents; Calorimetry, Differential Scanning; Camptothecin; Chromatography, High Pressure Liquid; Drug Carriers; Drug Delivery Systems; Drug Stability; Humans; In Vitro Techniques; Lactic Acid; Microscopy, Electron, Scanning; Nanomedicine; Nanoparticles; Neoplasms; Particle Size; Polyglycolic Acid; Polylactic Acid-Polyglycolic Acid Copolymer; X-Ray Diffraction
PubMed: 20957168
DOI: 10.2147/ijn.s11586 -
Neurologia Medico-chirurgica Oct 2006The topoisomerase I inhibitor, 9-nitro-camptothecin (9NC), is highly tumoricidal against glioblastoma multiforme (GBM) in vitro. However, systemic administration of 9NC...
The topoisomerase I inhibitor, 9-nitro-camptothecin (9NC), is highly tumoricidal against glioblastoma multiforme (GBM) in vitro. However, systemic administration of 9NC has not shown the expected efficacy in clinical trials. This failure may be due to the rapid hydrolysis of 9NC in plasma from the active form to the inactive and myelosuppressive form in the presence of human albumin at physiologic pH. Concurrent treatment with anticonvulsants and dexamethasone, drugs indispensable for the supportive therapy of patients with GBM, has also been shown to decrease plasma concentrations of these drugs. Intrathecal drug delivery circumvents the blood-brain barrier and minimizes systemic toxicity. Intrathecal delivery of 9NC may also have the more specific advantage of significantly reducing the hydrolysis of 9NC that occurs after systemic delivery due to the more favorable pH and reduced albumin content in cerebrospinal fluid. The present study evaluated the toxicity and efficacy of intrathecal delivery of 9NC in an athymic rat model of neoplastic meningitis. Toxicity tests showed that 0.3 micromol (5000 microM), 0.03 micromol (500 microM), 0.003 micromol (50 microM), or 0.0003 micromol (5 microM) of 9NC administered intrathecally to the athymic rats caused no evidence of clinical or histological toxicity. Intrathecal administration of 0.3 micromol (5000 microM) of 9NC twice a week for three doses to athymic rats with neoplastic meningitis induced by the GBM cell line, U87MGDeltaEGFR, resulted in a 26% increase of median survival compared to the control group (p < 0.005). These results suggest that intrathecal treatment with 9NC may be useful for patients with GBM neoplastic meningitis.
Topics: Animals; Antineoplastic Agents; Camptothecin; Disease Models, Animal; Glioblastoma; Injections, Spinal; Meningitis; Rats; Rats, Nude
PubMed: 17062987
DOI: 10.2176/nmc.46.485 -
Cancer Oct 2006Topoisomerase I inhibitors, like topotecan, have activity in myelodysplastic syndrome (MDS) and chronic myelomonocytic leukemia (CMML). 9-Nitro-camptothecin (9-NC) is a... (Clinical Trial)
Clinical Trial
BACKGROUND
Topoisomerase I inhibitors, like topotecan, have activity in myelodysplastic syndrome (MDS) and chronic myelomonocytic leukemia (CMML). 9-Nitro-camptothecin (9-NC) is a new oral topoisomerase inhibitor with a good safety profile. The aims of the current study were to evaluate the activity and safety of 9-NC in MDS and CMML.
METHODS
Adults with a diagnosis of MDS (n = 12) and CMML (n = 32) received 9-NC 2 mg/m(2) orally daily 5 days a week, every 4 to 6 weeks.
RESULTS
Overall, 5 (11%) patients achieved complete response (CR), 7 (16%) had a partial response (PR), and 6 (14%) had hematologic improvement (HI), for an overall response rate of 41%. The response rate was similar in MDS and CMML. Severe (Grade 3-4) side effects included nausea and vomiting (7%), diarrhea (18%), other gastrointestinal toxicities (5%), and genitourinary toxicities (12%).
CONCLUSIONS
9-NC is active in MDS and CMML. The paucity of available therapies in CMML makes 9-NC a good candidate for further studies as a single agent, or in combination with decitabine, 5-azacitidine or cytarabine.
Topics: Administration, Oral; Adult; Aged; Animals; Antineoplastic Agents; Camptothecin; Female; Humans; Leukemia, Myelomonocytic, Chronic; Male; Middle Aged; Myelodysplastic Syndromes; Topoisomerase I Inhibitors; Treatment Outcome
PubMed: 16955510
DOI: 10.1002/cncr.22186 -
The Oncologist Mar 2005Additional systemic treatments for locally advanced or metastatic pancreatic cancer are needed, as current treatment options produce only modest survival benefits.... (Clinical Trial)
Clinical Trial
BACKGROUND
Additional systemic treatments for locally advanced or metastatic pancreatic cancer are needed, as current treatment options produce only modest survival benefits. Rubitecan (Orathecin; Supergen Inc., Dublin, CA, http://www.supergen.com) is an orally active camptothecin derivative with demonstrated responses in patients with pancreatic cancer in early clinical trials. This phase II, open-label trial was developed to assess the safety and efficacy of rubitecan in patients with locally advanced or metastatic pancreatic cancer refractory to conventional chemotherapy.
METHODS
Fifty-eight patients with failed or relapsed advanced pancreatic cancer after receiving at least one prior chemotherapy regimen were enrolled to receive eight consecutive weeks of treatment with rubitecan at a dose of 1.5 mg/m2 orally on five consecutive days per week, followed by 2 days off therapy, repeatedly. The primary end point was response rate. Time to progression, overall survival, changes in CA19-9 levels, and the composite measure of clinical benefit response were evaluated as secondary end points.
RESULTS
Among 43 patients with measurable disease, 7% (3/43) achieved partial responses and 16% (7/43) had disease stabilization for an overall response and disease stabilization rate of 23%. All responses were confirmed by independent radiology review. Median survival was longer in responding patients than in the overall study cohort (10 months versus 3 months). Gastrointestinal and hematologic toxicities were the most commonly reported adverse events.
CONCLUSION
Oral rubitecan produced responses and was well tolerated by heavily pretreated patients with refractory pancreatic cancer. The overall risk-benefit profile of oral rubitecan appears promising, supporting further evaluation in phase III trials in patients with refractory and chemotherapy-naive pancreatic cancer.
Topics: Administration, Oral; Adult; Aged; Antineoplastic Agents; Camptothecin; Disease Progression; Female; Humans; Male; Middle Aged; Pancreatic Neoplasms; Survival Analysis
PubMed: 15793221
DOI: 10.1634/theoncologist.10-3-183 -
Bulletin Du Cancer Mar 2003Cancer occurs and it is life that runs off the rails. To restore the melody, the oncologist can use an array of pharmacological instruments which he needs to tune...
Cancer occurs and it is life that runs off the rails. To restore the melody, the oncologist can use an array of pharmacological instruments which he needs to tune optimally to reach the maximal efficacy. Camptothecin derivatives, inhibitors of topoisomerase I, represent an essential family of the chemotherapeutic arsenal. Topotecan and irinotecan have been used in the clinic for a number of years, but other potent analogues are appearing and broaden the range of topoisomerase I poisons. In this review, we present the main molecular characteristics of the second generation of camptothecins (lurtotecan, exatecan, rubitecan, silatecan). The future is also evoked with camptothecin derivatives bearing a modified lactone ring, in particular the homocamptothecins and the drug diflomotecan, which shows promise as an anticancer. The camptothecin partition is disclosed here.
Topics: Antineoplastic Agents; Camptothecin; Enzyme Inhibitors; Irinotecan; Music; Neoplasms; Organosilicon Compounds; Structure-Activity Relationship; Topoisomerase I Inhibitors; Topotecan
PubMed: 12801826
DOI: No ID Found