scholarly journals Detection of a G-Quadruplex as a Regulatory Element in Thymidylate synthase for Gene Silencing Using Polypurine Reverse Hoogsteen Hairpins

2020 ◽  
Vol 21 (14) ◽  
pp. 5028 ◽  
Author(s):  
Eva Aubets ◽  
Alex J. Félix ◽  
Miguel Garavís ◽  
Laura Reyes ◽  
Anna Aviñó ◽  
...  
Keyword(s):  
Thymidylate Synthase ◽  
Therapeutic Potential ◽  
Regulatory Element ◽  
Protein Levels ◽  
Dna And Rna ◽  
Dna Biosynthesis ◽  
Anti Cancer ◽  
G Quadruplex ◽  
Autoregulatory Mechanism ◽  
Synthetic Oligonucleotides

Thymidylate synthase (TYMS) enzyme is an anti-cancer target given its role in DNA biosynthesis. TYMS inhibitors (e.g., 5-Fluorouracil) can lead to drug resistance through an autoregulatory mechanism of TYMS that causes its overexpression. Since G-quadruplexes (G4) can modulate gene expression, we searched for putative G4 forming sequences (G4FS) in the TYMS gene that could be targeted using polypurine reverse Hoogsteen hairpins (PPRH). G4 structures in the TYMS gene were detected using the quadruplex forming G-rich sequences mapper and confirmed through spectroscopic approaches such as circular dichroism and NMR using synthetic oligonucleotides. Interactions between G4FS and TYMS protein or G4FS and a PPRH targeting this sequence (HpTYMS-G4-T) were studied by EMSA and thioflavin T staining. We identified a G4FS in the 5’UTR of the TYMS gene in both DNA and RNA capable of interacting with TYMS protein. The PPRH binds to its corresponding target dsDNA, promoting G4 formation. In cancer cells, HpTYMG-G4-T decreased TYMS mRNA and protein levels, leading to cell death, and showed a synergic effect when combined with 5-fluorouracil. These results reveal the presence of a G4 motif in the TYMS gene, probably involved in the autoregulation of TYMS expression, and the therapeutic potential of a PPRH targeted to the G4FS.

Phytochemical, Pharmacological Activities and Ayurvedic Significances of Magical Plant Mimosa pudica Linn

2020 ◽  
Vol 17 ◽  
Author(s):  
Vijay Kumar
Keyword(s):  
Therapeutic Potential ◽  
Wide Spectrum ◽  
Chemical Constituents ◽  
Future Research ◽  
Mimosa Pudica ◽  
Pharmacological Activities ◽  
Medicinal Uses ◽  
Traditional Medicines ◽  
Crude Extracts ◽  
Anti Cancer

: Mimosa pudica Linn is an integrated part of Traditional Medicines Systems of India, China, Africa, Korea and America. It has been used from centuries in traditional medicines to cure different diseases like fever, diabetes, constipation, jaundice, ulcers, biliousness, and dyspepsia. It is an important ingredient of wide class of herbal formulations. To assess the scientific evidence for therapeutic potential of Mimosa pudica Linn and to identify the gaps for future research. The available information on the ethno-medicinal uses, phytochemistry, pharmacology and toxicology of Mimosa pudica Linn was collected via a library and electronic searches in Sci-Finder, Pub-Med, Science Direct, Google Scholar for the period, 1990 to 2020. In traditional medicinal systems, variety of ethno-medicinal applications of Mimosa pudica Linn has been noticed. Phytochemical investigation has resulted in identification of 40 well known chemical constituents, among which alkaloids, phenols and flavionoids are the predominant groups. The crude extracts and isolates have exhibited a wide spectrum of in vitro and in vivo pharmacological activities including anti-cancer, anti-inflammation, osteoporosis, neurological disorders, hypertension etc.. To quantify the Mimosa pudica Linn and its formulations, analytical techniques like HPLC and HPTLC has shown dominancy with good range of recovery and detection limit. Mimosa pudica Linn is the well-known herb since an ancient time. The pharmacological results supported some of the applications of Mimosa pudica Linn in traditional medicine systems. Perhaps, the predominance of alkaloids, phenols and flavionoids are responsible for the pharmacological activities the crude extracts and isolates of Mimosa pudica Linn. Further, there is need to isolate and evaluate the active chemical constituents of Mimosa pudica Linn having significant medicinal values. In future, it is important to study the exact mechanism associated with the phytochemicals of Mimosa pudica Linn especially on anti-cancer activities. Notably, toxicity studies on Mimosa pudica Linn are limited which are to be explored in future for the safe application of Mimosa pudica Linn and its formulations.

scholarly journals Skullcapflavone II Suppresses TNF-α/IFN-γ-Induced TARC, MDC, and CTSS Production in HaCaT Cells

2021 ◽  
Vol 22 (12) ◽  
pp. 6428
Author(s):  
Hanon Lee ◽  
Dong Hun Lee ◽  
Jang-Hee Oh ◽  
Jin Ho Chung
Keyword(s):  
P38 Mapk ◽  
Therapeutic Potential ◽  
Inflammatory Diseases ◽  
Mapk Signaling ◽  
Hacat Cells ◽  
Protein Levels ◽  
Tnf Α ◽  
Ifn Γ ◽  
Mapk Signaling Pathways ◽  
Pro Inflammatory Cytokines

Skullcapflavone II (SFII), a flavonoid derived from Scutellaria baicalensis, has been reported to have anti-inflammatory properties. However, its therapeutic potential for skin inflammatory diseases and its mechanism are unknown. Therefore, this study aimed to investigate the effect of SFII on TNF-α/IFN-γ-induced atopic dermatitis (AD)-associated cytokines, such as thymus- and activation-regulated chemokine (TARC) and macrophage-derived chemokine (MDC). Co-stimulation with TNF-α/IFN-γ in HaCaT cells is a well-established model for induction of pro-inflammatory cytokines. We treated cells with SFII prior to TNF-α/IFN-γ-stimulation and confirmed that it significantly inhibited TARC and MDC expression at the mRNA and protein levels. Additionally, SFII also inhibited the expression of cathepsin S (CTSS), which is associated with itching in patients with AD. Using specific inhibitors, we demonstrated that STAT1, NF-κB, and p38 MAPK mediate TNF-α/IFN-γ-induced TARC and MDC, as well as CTSS expression. Finally, we confirmed that SFII significantly suppressed TNF-α/IFN-γ-induced phosphorylation of STAT1, NF-κB, and p38 MAPK. Taken together, our study indicates that SFII inhibits TNF-α/IFN-γ-induced TARC, MDC, and CTSS expression by regulating STAT1, NF-κB, and p38 MAPK signaling pathways.

scholarly journals Nucleoside Analogues Are Potent Inducers of Pol V-mediated Mutagenesis

Biomolecules ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 843
Author(s):  
Balagra Kasim Sumabe ◽  
Synnøve Brandt Ræder ◽  
Lisa Marie Røst ◽  
Animesh Sharma ◽  
Eric S. Donkor ◽  
...  
Keyword(s):  
Mammalian Cells ◽  
Mutation Frequency ◽  
Nucleoside Analogues ◽  
Cancer Therapies ◽  
E Coli ◽  
Replicative Stress ◽  
Pol V ◽  
Dna And Rna ◽  
Sos Induction ◽  
Anti Cancer

Drugs targeting DNA and RNA in mammalian cells or viruses can also affect bacteria present in the host and thereby induce the bacterial SOS system. This has the potential to increase mutagenesis and the development of antimicrobial resistance (AMR). Here, we have examined nucleoside analogues (NAs) commonly used in anti-viral and anti-cancer therapies for potential effects on mutagenesis in Escherichia coli, using the rifampicin mutagenicity assay. To further explore the mode of action of the NAs, we applied E. coli deletion mutants, a peptide inhibiting Pol V (APIM-peptide) and metabolome and proteome analyses. Five out of the thirteen NAs examined, including three nucleoside reverse transcriptase inhibitors (NRTIs) and two anti-cancer drugs, increased the mutation frequency in E. coli by more than 25-fold at doses that were within reported plasma concentration range (Pl.CR), but that did not affect bacterial growth. We show that the SOS response is induced and that the increase in mutation frequency is mediated by the TLS polymerase Pol V. Quantitative mass spectrometry-based metabolite profiling did not reveal large changes in nucleoside phosphate or other central carbon metabolite pools, which suggests that the SOS induction is an effect of increased replicative stress. Our results suggest that NAs/NRTIs can contribute to the development of AMR and that drugs inhibiting Pol V can reverse this mutagenesis.

scholarly journals G-quadruplex binding properties of a potent PARP-1 inhibitor derived from 7-azaindole-1-carboxamide

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sabrina Dallavalle ◽  
Loana Musso ◽  
Roberto Artali ◽  
Anna Aviñó ◽  
Leonardo Scaglioni ◽  
...  
Keyword(s):  
Therapeutic Potential ◽  
Parp Inhibition ◽  
Inhibition Mechanism ◽  
Binding Properties ◽  
Dna Oligomers ◽  
Quadruplex Dna ◽  
G Quadruplex ◽  
Molecular Bases ◽  
Dna Binding Properties ◽  
Parp 1

AbstractPoly ADP-ribose polymerases (PARP) are key proteins involved in DNA repair, maintenance as well as regulation of programmed cell death. For this reason they are important therapeutic targets for cancer treatment. Recent studies have revealed a close interplay between PARP1 recruitment and G-quadruplex stabilization, showing that PARP enzymes are activated upon treatment with a G4 ligand. In this work the DNA binding properties of a PARP-1 inhibitor derived from 7-azaindole-1-carboxamide, (2-[6-(4-pyrrolidin-1-ylmethyl-phenyl)-pyrrolo[2,3-b]pyridin-1-yl]-acetamide, compound 1) with model duplex and quadruplex DNA oligomers were studied by NMR, CD, fluorescence and molecular modelling. We provide evidence that compound 1 is a strong G-quadruplex binder. In addition we provide molecular details of the interaction of compound 1 with two model G-quadruplex structures: the single repeat of human telomeres, d(TTAGGGT)4, and the c-MYC promoter Pu22 sequence. The formation of defined and strong complexes with G-quadruplex models suggests a dual G4 stabilization/PARP inhibition mechanism of action for compound 1 and provides the molecular bases of its therapeutic potential.

scholarly journals The HGR motif is the antiangiogenic determinant of vasoinhibin: implications for a therapeutic orally active oligopeptide

Angiogenesis ◽  
2021 ◽  
Author(s):  
Juan Pablo Robles ◽  
Magdalena Zamora ◽  
Lourdes Siqueiros-Marquez ◽  
Elva Adan-Castro ◽  
Gabriela Ramirez-Hernandez ◽  
...  
Keyword(s):  
Therapeutic Agent ◽  
Clinical Evidence ◽  
Therapeutic Potential ◽  
Peripartum Cardiomyopathy ◽  
Loss Of Function ◽  
Functional Determinant ◽  
Melanoma Tumor ◽  
Linear Motif ◽  
Anti Cancer ◽  
Orally Active

AbstractThe hormone prolactin acquires antiangiogenic and antivasopermeability properties after undergoing proteolytic cleavage to vasoinhibin, an endogenous prolactin fragment of 123 or more amino acids that inhibits the action of multiple proangiogenic factors. Preclinical and clinical evidence supports the therapeutic potential of vasoinhibin against angiogenesis-related diseases including diabetic retinopathy, peripartum cardiomyopathy, rheumatoid arthritis, and cancer. However, the use of vasoinhibin in the clinic has been limited by difficulties in its production. Here, we removed this barrier to using vasoinhibin as a therapeutic agent by showing that a short linear motif of just three residues (His46-Gly47-Arg48) (HGR) is the functional determinant of vasoinhibin. The HGR motif is conserved throughout evolution, its mutation led to vasoinhibin loss of function, and oligopeptides containing this sequence inhibited angiogenesis and vasopermeability with the same potency as whole vasoinhibin. Furthermore, the oral administration of an optimized cyclic retro-inverse vasoinhibin heptapeptide containing HGR inhibited melanoma tumor growth and vascularization in mice and exhibited equal or higher antiangiogenic potency than other antiangiogenic molecules currently used as anti-cancer drugs in the clinic. Finally, by unveiling the mechanism that obscures the HGR motif in prolactin, we anticipate the development of vasoinhibin-specific antibodies to solve the on-going challenge of measuring endogenous vasoinhibin levels for diagnostic and interventional purposes, the design of vasoinhibin antagonists for managing insufficient angiogenesis, and the identification of putative therapeutic proteins containing HGR.

scholarly journals Molecular and Biochemical Basis of Minocycline-Induced Hyperpigmentation—The Study on Normal Human Melanocytes Exposed to UVA and UVB Radiation

2021 ◽  
Vol 22 (7) ◽  
pp. 3755
Author(s):  
Jakub Rok ◽  
Zuzanna Rzepka ◽  
Justyna Kowalska ◽  
Klaudia Banach ◽  
Artur Beberok ◽  
...  
Keyword(s):  
Uv Radiation ◽  
Therapeutic Potential ◽  
Melanin Synthesis ◽  
Uvb Radiation ◽  
Biochemical Basis ◽  
Skin Hyperpigmentation ◽  
Human Melanocytes ◽  
Anti Cancer ◽  
Normal Human

Minocycline is a drug which induces skin hyperpigmentation. Its frequency reaches up to 50% of treated patients. The adverse effect diminishes the great therapeutic potential of minocycline, including antibacterial, neuroprotective, anti-inflammatory and anti-cancer actions. It is supposed that an elevated melanin level and drug accumulation in melanin-containing cells are related to skin hyperpigmentation. This study aimed to evaluate molecular and biochemical mechanism of minocycline-induced hyperpigmentation in human normal melanocytes, as well as the contribution of UV radiation to this side effect. The experiments involved the evaluation of cyto- and phototoxic potential of the drug using cell imaging with light and confocal microscopes as well as biochemical and molecular analysis of melanogenesis. We showed that minocycline induced melanin synthesis in epidermal melanocytes. The action was intensified by UV irradiation, especially with the UVB spectrum. Minocycline stimulated the expression of microphthalmia-associated transcription factor (MITF) and tyrosinase (TYR) gene. Higher levels of melanin and increased activity of tyrosinase were also observed in treated cells. Moreover, minocycline triggered the supranuclear accumulation of tyrosinase, similar to UV radiation. The decreased level of premelanosome protein PMEL17 observed in all minocycline-treated cultures suggests disorder of the formation, maturation or distribution of melanosomes. The study revealed that minocycline itself was able to enhance melanin synthesis. The action was intensified by irradiation, especially with the UVB spectrum. Demonstrated results confirmed the potential role of melanin and UV radiation minocycline-induced skin hyperpigmentation.

scholarly journals Dietary Curcumin: Correlation between Bioavailability and Health Potential

Nutrients ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 2147 ◽  
Author(s):  
Michele Dei Cas ◽  
Riccardo Ghidoni
Keyword(s):  
Small Intestine ◽  
Cellular Uptake ◽  
Oral Delivery ◽  
Therapeutic Potential ◽  
Pharmacokinetic Profile ◽  
Yellow Pigment ◽  
The Body ◽  
Anti Cancer ◽  
Poor Absorption ◽  
Oral Delivery Systems

The yellow pigment curcumin, extracted from turmeric, is a renowned polyphenol with a broad spectrum of health properties such as antioxidant, anti-inflammatory, anti-cancer, antidiabetic, hepatoprotective, anti-allergic, anti-dermatophyte, and neuroprotective. However, these properties are followed by a poor pharmacokinetic profile which compromises its therapeutic potential. The association of low absorption by the small intestine and the extensive reductive and conjugative metabolism in the liver dramatically weakens the oral bioavailability. Several strategies such as inhibition of curcumin metabolism with adjuvants as well as novel solid and liquid oral delivery systems have been tried to counteract curcumin poor absorption and rapid elimination from the body. Some of these drug deliveries can successfully enhance the solubility, extending the residence in plasma, improving the pharmacokinetic profile and the cellular uptake.

Targeting G-quadruplex DNA as Potential Anti-cancer Therapy

2017 ◽  
pp. 129-162
Author(s):  
Riccardo Bonsignore ◽  
Elisa Trippodo ◽  
Giampaolo Barone
Keyword(s):  
Cancer Therapy ◽  
Quadruplex Dna ◽  
Anti Cancer ◽  
G Quadruplex

scholarly journals Development of Small-Molecule STING Activators for Cancer Immunotherapy

Biomedicines ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 33
Author(s):  
Hee Ra Jung ◽  
Seongman Jo ◽  
Min Jae Jeon ◽  
Hyelim Lee ◽  
Yeonjeong Chu ◽  
...  
Keyword(s):  
Cancer Immunotherapy ◽  
Cyclic Gmp ◽  
Therapeutic Potential ◽  
Interferon Response ◽  
Type I ◽  
Anti Cancer ◽  
Cancer Agent ◽  
Sting Pathway

In cancer immunotherapy, the cyclic GMP–AMP synthase–stimulator of interferon genes (STING) pathway is an attractive target for switching the tumor immunophenotype from ‘cold’ to ‘hot’ through the activation of the type I interferon response. To develop a new chemical entity for STING activator to improve cyclic GMP-AMP (cGAMP)-induced innate immune response, we identified KAS-08 via the structural modification of DW2282, which was previously reported as an anti-cancer agent with an unknown mechanism. Further investigation revealed that direct STING binding or the enhanced phosphorylation of STING and downstream effectors were responsible for DW2282-or KAS-08-mediated STING activity. Furthermore, KAS-08 was validated as an effective STING pathway activator in vitro and in vivo. The synergistic effect of cGAMP-mediated immunity and efficient anti-cancer effects successfully demonstrated the therapeutic potential of KAS-08 for combination therapy in cancer treatment.

Sign in / Sign up

Export Citation Format

Share Document