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The Advantages and Versatility of Carrier-Free Nanodrug and Nanoparticle Systems for Cancer Therapy
Published in Loutfy H. Madkour, Nanoparticle-Based Drug Delivery in Cancer Treatment, 2022
Camptothecin (CPT), extracted from Chinese ornamental tree, works by inhibiting the topoisomerase-1 pathway that then prevents DNA re-ligation, resulting in cell death [431]. CPT is mainly used for the treatments of lung, breast, and brain cancers and has a planar pentacyclic ring structure that causes cylindrical-shaped aggregations in water. Biological environment causes the degradation of CPT in only 30 min by hydrolysis of its lactone rings, and CPT has very poor water solubility (2–3 μg/mL) [432,433]. Therefore, derivatives of CPT have been developed in order to increase its solubility and stability in physiological conditions. 7-Ethyl-10-hydroxy-camptothecin (SN-38), a semisynthetic derivative of CPT, is effective on a wide range of solid tumors by inhibiting topoisomerase-1 [434]. SN-38 has two hydroxyl groups that can bond with different molecules and produce more efficient formulations. 10-Hydroxycamptothecin (HCPT), another analogue of CPT, is known to have an antitumor effect against gastric carcinoma, hepatoma, leukemia, and head and neck tumors [435]. It is demonstrated that compared to CPT, HCPT is more potent and less toxic in animal studies and in human clinical evaluation. However, the clinical applications of both SN-38 and HCPT are limited, again, due to their low water solubility, 11–38 and 7.2 μg/mL, respectively [436–438]. DOX, also a topoisomerase inhibitor which exerts its activity on topoisomerase II, causes DNA damage and prevents mitosis in tumor cells [439,440]. It is widely used to treat breast cancer, urothelial cancer, hematopoietic malignancies, and solid tumors.
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Published in Valerio Voliani, Nanomaterials and Neoplasms, 2021
Joseph M. Caster, Artish N. Patel, Tian Zhang, Andrew Wang
Nippon Kayaku Inc. currently has two polymeric nanoparticle drugs in development, NK012 and NK015. NK012 is a polymeric formulation of SN-38 (the active metabolite of the topoisomerase inhibitor irinotecan). This drug has completed two phase I studies (results pending) and there are currently several ongoing phase II trials [35]. NK015 is a polymeric formulation of paclitaxel. Similar to other nanoformulations of paclitaxel, early phase trials are showing that NK015 has a more favorable toxicity profile than solvent-based Taxol and may have increased efficacy [36–38]. There is currently an ongoing phase III study comparing NK015 to Cremophor-based paclitaxel for the treatment of metastatic breast cancer. In addition to these two compounds, there are preclinical data for a third compound, NK911. This is a polymeric formulation of doxorubicin, which appears to have lower stability and more rapid release than the approved liposomal doxorubicin formulation, Doxil [39]. This drug has completed phase I and has a good safety profile [40]. but there are no current or ongoing studies, and it is unclear if further clinical development will be pursued.
Advanced materials and technologies for oral diseases
Published in Science and Technology of Advanced Materials, 2023
Hao Cui, Yan You, Guo-Wang Cheng, Zhou Lan, Ke-Long Zou, Qiu-Ying Mai, Yan-Hua Han, Hao Chen, Yu-Yue Zhao, Guang-Tao Yu
Atipine (QC), an anti-malarial drug, was found to produce anticancer effects by acting as a DNA inserter and topoisomerase inhibitor. Some scholars processed gold nanoparticles with QC and showed that the synthesized hybrid nanoparticles could significantly inhibit cell proliferation, cause apoptosis, and disrupt angiogenesis and tumor regression in vitro [260]. miR-214 has been identified as a promoter of OSCC invasion and metastasis [261]. Using the excellent physicochemical properties and strong adsorption of graphene nanomaterials to process miR-214 inhibitors, the results demonstrate that this inhibitor can effectively inhibit intracellular miR-214, reduce OSCC cell invasion and migration by targeting PTEN and p53, and increase cell apoptosis [262,263].
Valuable alkaloids content is preserved in Camptotheca acuminata and Morus alba grown in trace elements contaminated soil
Published in International Journal of Phytoremediation, 2022
Julien Lamontagne, Eszter Sas, Gilles Vincent, Kankan Shang, Frédéric E. Pitre, Michel Labrecque
Wood phytochemicals include alkaloids, a broad and diverse group of nitrogen-containing molecules that are specific to genera or few species (Desgagné-Penix 2017). Alkaloids comprise very potent modulators of biological activities, like caffeine and quinine (Desgagné-Penix 2017). Less known alkaloids are the alpha-glucosidase inhibitor 1-deoxynojirimycin (DNJ), found in Morus alba, and the type I topoisomerase inhibitor camptothecin (CPT), isolated from Camptotheca acuminata. The former has antidiabetic properties (Desgagné-Penix 2017), while the latter is used in the synthesis of an anticancer drug (Isah 2016).
Copper(II) and cobalt(II) complexes of 5-methyl pyrazole-3-carboxylic acid: synthesis, X-ray crystallography, thermal analysis and in vitro antimicrobial activity
Published in Journal of Coordination Chemistry, 2018
Ananyakumari Santra, Paula Brandao, Harekrishna Jana, Gopinath Mondal, Pradip Bera, Abhimanyu Jana, Pulakesh Bera
The diploid nature and longer generation time of fungi compared to bacteria make them different with respect to interaction with antimicrobial agents [39–41]. Most of the antibacterial agents inhibit the formation of peptidoglycan of cell wall resulting in cell death. Other prominent ways to destroy bacteria are protein synthesis inhibitors, topoisomerase inhibitor and metabolic pathway inhibitor. Whereas most antifungal agents target the formation and function of ergosterol which is an important component of fungal cell membrane. The ability of the ligands and complexes to inhibit the growth of several bacteria and fungi are assessed using disc diffusion, agar well diffusion and minimum inhibitory assays. The in vitro antimicrobial activities are given in Table 5 and MIC values of the compounds are presented in Table 6. Camera views of the agar experiments are provided in the Supplementary Data (Figure S5). Results show that the antimicrobial activities of the complexes are greater than the ancillary ligands, i.e. Hmpca and mpch. This can be explained on the basis of lipophilic character of the compounds. The lipophilicity of a compound is the measure of cell membrane permeation. Mostly disposition ability of a drug depends on the capacity to cross the cell membrane [11, 42]. The general trend of the logP (where P is the partition coefficient) values is 0.645 (3) > 0.396 (1) > 0.253 (Hmpca) > 0.174 (mpch) > 0.101 (2) (Table 1). The antibacterial effect of the tested compounds follows the above logP order. Complex 3 has the highest logP (0.645) and exhibits the highest antimicrobial property. The lowest logP value is attesting the lowest activity of 2. The polymeric nature of 2 restricts the distribution of molecule in the organic (1-octanol) phase compared to monomeric complexes 1 and 3. The logP order among the ligands can be explained considering the increased polarity of the ligands. 5-Methyl pyrazole carbohydrazide (mpch) and/or 5-methyl pyrazole 3-carboxylic acid (Hmpca) is expected to have higher polarity than the metal complexes. Both the ligands, mpch and Hmpca, which differ from each other solely by their functional group, exhibit low antibacterial activity (MIC values 500 − 600 µg mL−1) against K. pneumonia and C. albicans compared to metal complexes. The complexes obtained from the reaction of ligand and metal ions are where the primary charge(s) of the metal ion is satisfied by the ligand molecule. The absence of any free anion(s) in the complexes makes them lipophilic in nature. Lipophilicity of compound favors permeation through the lipid layer of the cell membrane. The present study concludes that complexes with high logP show better antimicrobial activity than the original chelator. Among the complexes, cobalt(II) complex (3) exhibits the greatest antimicrobial activity with MIC values 25 − 100 µg mL−1 and the lowest activity is exhibited by polymeric 2 against different bacteria and fungi. These findings are graphically represented in Figure 9.