The coronavirus disease of 2019 (COVID-19) pandemic launched an unprecedented global effort to rapidly develop vaccines to stem the spread of the novel severe acute respiratory syndrome coronavirus (SARS-CoV-2). Messenger ribonucleic acid (mRNA) vaccines were developed quickly by companies that were actively developing mRNA therapeutics and vaccines for other indications, leading to two mRNA vaccines being not only the first SARS-CoV-2 vaccines to be approved for emergency use but also the first mRNA drugs to gain emergency use authorization and to eventually gain full approval. This was possible partly because mRNA sequences can be altered to encode nearly any protein without significantly altering its chemical properties, allowing the drug substance to be a modular component of the drug product.
View Article and Find Full Text PDFBackground: The reduced renal function has prognostic significance in COVID-19 and it has been linked to mortality in the general population. Reduced renal function is prevalent in older age and thus we set out to better understand its effect on mortality.
Methods: Patient clinical and demographic data was taken from the COVID-19 in Older People (COPE) study during two periods (February-June 2020 and October 2020-March 2021, respectively).
NUP98-NSD1-positive acute myeloid leukemia (AML) is a poor prognostic subgroup that is frequently diagnosed in pediatric cytogenetically normal AML. NUP98-NSD1-positive AML often carries additional mutations in genes including and . The purpose of our study was to characterize the cooperative potential of the fusion and its associated Neuroblastoma rat sarcoma (NRAS) mutation.
View Article and Find Full Text PDFEfficient and safe delivery of siRNA in vivo is the biggest roadblock to clinical translation of RNA interference (RNAi)-based therapeutics. To date, lipid nanoparticles (LNPs) have shown efficient delivery of siRNA to the liver; however, delivery to other organs, especially hematopoietic tissues still remains a challenge. We developed DLin-MC3-DMA lipid-based LNP-siRNA formulations for systemic delivery against a driver oncogene to target human chronic myeloid leukemia (CML) cells in vivo.
View Article and Find Full Text PDFLipid nanoparticles (LNPs) are established in the biopharmaceutical industry for efficient encapsulation and cytosolic delivery of nucleic acids for potential therapeutics, with several formulations in clinical trials. The advantages of LNPs can also be applied in basic research and discovery with a microfluidic method of preparation now commercially available that allows preparations to be scaled down to quantities appropriate for cell culture. These preparations conserve expensive nucleic acids while maintaining the particle characteristics that have made LNPs successful in later stages of genetic medicine development.
View Article and Find Full Text PDFJ Drug Target
November 2016
Microfluidic devices are mircoscale fluidic circuits used to manipulate liquids at the nanoliter scale. The ability to control the mixing of fluids and the continuous nature of the process make it apt for solvent/antisolvent precipitation of drug-delivery nanoparticles. This review describes the use of numerous microfluidic designs for the formulation and production of lipid nanoparticles, liposomes and polymer nanoparticles to encapsulate and deliver small molecule or genetic payloads.
View Article and Find Full Text PDFA simple, efficient, and scalable manufacturing technique is required for developing siRNA-lipid nanoparticles (siRNA-LNP) for therapeutic applications. In this chapter we describe a novel microfluidic-based manufacturing process for the rapid manufacture of siRNA-LNP, together with protocols for characterizing the size, polydispersity, RNA encapsulation efficiency, RNA concentration, and total lipid concentration of the resultant nanoparticles.
View Article and Find Full Text PDFPurpose: A liposomal irinotecan formulation referred to as Irinophore C relies on the ability of copper to complex irinotecan within the liposome. It is currently being evaluated for critical drug-loading parameters. Studies presented here were designed to determine the optimum copper concentration required for the effective encapsulation and retention of irinotecan into liposomes.
View Article and Find Full Text PDF5-Fluorouracil (5-FU) is a small, very membrane permeable drug that is poorly retained within the aqueous compartment of liposomal nanoparticles (LNP). To address this problem a novel method relying on formation of a ternary complex comprising copper, low molecular weight polyethylenimine (PEI) and 5-FU has been developed. More specifically, in the presence of entrapped copper and PEI, externally added 5-FU can be efficiently encapsulated (>95%) in DSPC/Chol (1,2-Distearoyl-sn-Glycero-3-Phosphocholine/cholesterol; 55:45 mol%) liposomes (130-170 nm) to achieve drug-to-lipid ratios of 0.
View Article and Find Full Text PDFBackground: Docetaxel is one of the few chemotherapeutic drugs that are considered highly effective when used to treat prostate cancer patients that have relapsed and/or metastatic disease, it is therefore reasonable to expect further improvements in treatment outcomes when it is combined with other therapeutic agents active in prostate cancer. This study assesses the combination of well tolerated and orally bioavailable formulations of ginsenoside Rh2 or its aglycone aPPD with docetaxel.
Methods: The in vitro activity of Rh2, aPPD, and docetaxel was determined in four prostate cancer cell lines: PC-3, LNCaP, DU145, and C4-2.
Cationic liposomes exhibit a propensity to selectively target tumor-associated blood vessels demonstrating potential value as anti-cancer drug delivery vehicles. Their utility however, is hampered by their biological instability and rapid elimination following i.v.
View Article and Find Full Text PDFPurpose: To examine the antitumor effects of Irinophore C, a nanopharmaceutical formulation of irinotecan, on the tissue morphology and function of tumor vasculature in HT-29 human colorectal tumors.
Experimental Design: Fluorescence microscopy was used to map and quantify changes in tissue density, tumor vasculature, hypoxia, and the distribution of Hoechst 33342, a perfusion marker, and the anticancer drug, doxorubicin. Noninvasive magnetic resonance imaging was used to quantify Ktrans, the volume transfer constant of a solute between the blood vessels and extracellular tissue compartment of the tumor, as a measure of vascular function.
Purpose: To assess the pharmacokinetics, tumor drug accumulation, and therapeutic activity of Irinophore C, a novel liposomal formulation of irinotecan (CPT-11).
Experimental Design: The plasma lactone/carboxy levels of CPT-11 and SN-38 were determined in mice after a single i.v.
We determined whether the method used to encapsulate irinotecan into 1,2-distearoyl-sn-glycero-phosphocholine/cholesterol (DSPC/Chol; 55:45 mol%) liposomes influenced: (i) irinotecan release rate and (ii) therapeutic efficacy. DSPC/Chol (55:45 mol%) liposomes were prepared with: (i) unbuffered CuSO4; (ii) buffered (pH 7.5) CuSO4; (iii) unbuffered MnSO4 and the ionophore A23187 (exchanges internal metal2+ with external 2H+ to establish and maintain a transmembrane pH gradient); and (iv) unbuffered CuSO4 and ionophore A23187.
View Article and Find Full Text PDFBreast Cancer Res Treat
December 2007
Developing novel synergistic and more effective combination treatments is necessary for better management of breast cancer in the clinic. It is established that HER-2 overexpressing breast cancers are sensitive to the HER-1 (epidermal growth factor receptor (EGFR)) inhibitor gefitinib, but that this targeted agent produces only moderate therapeutic effects in vivo. Here, we use a model of ER(+) HER-2 overexpressing MCF-7 breast cancer (MCF-7(HER-2)) to identify, as broadly as possible, the in vivo microenvironmental and molecular therapeutic responses to gefitinib to predict a therapeutically viable target for gefitinib-based combination treatment.
View Article and Find Full Text PDFPurpose: To determine whether entrapped transition metals could mediate the active encapsulation of the anticancer drug irinotecan into preformed liposomes. Further, to establish that metal complexation could stabilize liposomal irinotecan in the therapeutically active lactone conformation.
Materials And Methods: Irinotecan was added to preformed 1,2-distearoyl-sn-glycero-phosphocholine/cholesterol (DSPC/chol) liposomes prepared in CuSO4, ZnSO4, MnSO4, or CoSO4 solutions, and drug encapsulation was determined over time.
Purpose: The use of in vitro drug cytotoxicity assays for the assessment of drug-drug interactions that lead to synergy may not take into account the many cellular determinants responsible for combination effects. Administration of the anticancer drug CPT-11, for example, is associated with rapid conversion of drug from its active lactone form to the inactive carboxylate form. Thus it is difficult to model, in vitro, the behavior of this drug when used as a single agent and when used in a combination setting, this factor may contribute to the interactions measured.
View Article and Find Full Text PDFThe advent of sophisticated experimental tools that can probe the molecular pathology of cancer has revealed a number of genes and gene families that could prove attractive targets for cancer therapy. Thus, gene silencing strategies have been envisioned to treat cancer by targeting the cancer cell's capacity to: (I) resist conventional treatment methods (chemotherapy and radiotherapy), (II) promote angiogenesis, and (III) metastasize and/or to survive microenvironments that normally would promote cell apoptosis/necrosis. The realization of such strategies is limited by the lack of pharmaceutically-viable technologies that enable the safe and effective delivery of gene-targeting agents to neoplastic cells following systemic administration.
View Article and Find Full Text PDFAnticancer drug combinations can act synergistically or antagonistically against tumor cells in vitro depending on the ratios of the individual agents comprising the combination. The importance of drug ratios in vivo, however, has heretofore not been investigated, and combination chemotherapy treatment regimens continue to be developed based on the maximum tolerated dose of the individual agents. We systematically examined three different drug combinations representing a range of anticancer drug classes with distinct molecular mechanisms (irinotecan/floxuridine, cytarabine/daunorubicin, and cisplatin/daunorubicin) for drug ratio-dependent synergy.
View Article and Find Full Text PDFThese studies describe the role of transition metal ions in the liposomal encapsulation of topotecan. Liposomes (1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) and cholesterol (CH) (55:45, mole ratio)) were prepared with manganese (Mn), copper (Cu), zinc (Zn) or cobalt (Co) ion gradients (metal inside). Subsequently, topotecan was added to the liposome exterior (final drug-to-lipid ratio (mol/mol) of 0.
View Article and Find Full Text PDFThe introduction of combination chemotherapeutic regimens for the treatment of childhood leukaemia in the 1960s provided the proof-of-principle that cytotoxic drugs were capable of curing cancer. However, in the four decades since this discovery, the majority of cancers still cannot be cured by chemotherapy. Clinical evidence supports the hypothesis of Goldie and Coldman that treating cancers with all the available effective agents simultaneously provides the greatest chance of eliciting a cure.
View Article and Find Full Text PDFPurpose: The purpose is to demonstrate whether an appropriately designed liposomal formulation of irinotecan is effective in treating mice with liver-localized colorectal carcinomas.
Experimental Design: Irinotecan was encapsulated in 1,2-distearoyl-sn-glycero-3-phosphocholine/cholesterol (55:45 molar ratio) liposomes using an ionophore (A23187)-generated transmembrane proton gradient. This formulation was evaluated in vivo by measuring plasma elimination of liposomal lipid and drug after i.
A novel technique is demonstrated for the imaging of turbulent flows in which a single window to the flow is the only optical access required. A femtosecond laser is used to excite two-photon fluorescence in a disodium-fluorescein-seeded water jet. The fluorescence signal is generated at only the focal point of the laser because of the highly nonlinear nature of the two-photon absorption, and it is collected in a direction counterpropagating to the excitation beam.
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