Identifying the Cellular Target of a Cordyheptapeptide A and Synthetic Derivatives

: During cancer progression, the unrestricted proliferation of cells is supported by the impaired cell death response provoked by certain oncogenes. Both autophagy and apoptosis are the signaling pathways of cell death, which are targeted for cancer treatment. Defects in apoptosis result in reduced cell death and ultimately tumor progression. The tumor cells lacking apoptosis phenomena are killed by ROS- mediated autophagy. The autophagic programmed cell death requires apoptosis protein for inhibiting tumor growth; thus, the interconnection between these two pathways determines the fate of a cell. The cross-regulation of autophagy and apoptosis is an important aspect to modulate autophagy, apoptosis and to sensibilise apoptosis-resistant tumor cells under metabolic stress and might be a rational approach for drug designing strategy for the treatment of cancer. Numerous proteins involved in autophagy have been investigated as the druggable target for anticancer therapy. Several compounds of natural origin have been reported, to control autophagy activity through the PI3K/Akt/mTOR key pathway. Diosgenin, a steroidal sapogenin has emerged as a potential candidate for cancer treatment. It induces ROS-mediated autophagy, inhibits PI3K/Akt/mTOR pathway, and produces cytotoxicity selectively in cancer cells. This review aims to focus on optimal strategies using diosgenin to induce apoptosis by modulating the pathways involved in autophagy regulation and its potential implication in the treatment of various cancer. The discussion has been extended to the medicinal chemistry of semi-synthetic derivatives of diosgenin exhibiting anticancer activity.

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Recent Patents on Anti-Cancer Potential of Helenalin

Recent Patents on Anti-Cancer Drug Discovery ◽

10.2174/1574892815666200702142601 ◽

2020 ◽

Vol 15 (2) ◽

pp. 132-142

Author(s):

Priyanka Kriplani ◽

Kumar Guarve

Keyword(s):

Synergistic Effects ◽

Therapeutic Interventions ◽

Active Constituent ◽

Scientific Impact ◽

Isolation Techniques ◽

Anti Cancer ◽

Prevention Of Cancer ◽

Synthetic Derivatives

Background: Arnica montana, containing helenalin as its principal active constituent, is the most widely used plant to treat various ailments. Recent studies indicate that Arnica and helenalin provide significant health benefits, including anti-inflammatory, neuroprotective, antioxidant, cholesterol-lowering, immunomodulatory, and most important, anti-cancer properties. Objective: The objective of the present study is to overview the recent patents of Arnica and its principal constituent helenalin, including new methods of isolation, and their use in the prevention of cancer and other ailments. Methods: Current prose and patents emphasizing the anti-cancer potential of helenalin and Arnica, incorporated as anti-inflammary agents in anti-cancer preparations, have been identified and reviewed with particular emphasis on their scientific impact and novelty. Results: Helenalin has shown its anti-cancer potential to treat multiple types of tumors, both in vitro and in vivo. It has also portrayed synergistic effects when given in combination with other anti- cancer drugs or natural compounds. New purification/isolation techniques are also developing with novel helenalin formulations and its synthetic derivatives have been developed to increase its solubility and bioavailability. Conclusion: The promising anti-cancer potential of helenalin in various preclinical studies may open new avenues for therapeutic interventions in different tumors. Thus clinical trials validating its tumor suppressing and chemopreventive activities, particularly in conjunction with standard therapies, are immediately required.

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Synthesis, Cytotoxicity and Antioxidant Activity of New Analogs of RC-121 Synthetic Derivatives of Somatostatin

Anti-Cancer Agents in Medicinal Chemistry ◽

10.2174/1871520618666180417164344 ◽

2019 ◽

Vol 18 (10) ◽

pp. 1417-1424 ◽

Cited By ~ 2

Author(s):

Emilia Naydenova ◽

Diana Wesselinova ◽

Svetlana Staykova ◽

Ivan Goshev ◽

Ljubomir Vezenkov

Keyword(s):

Antioxidant Activity ◽

Antioxidant Capacity ◽

Cell Line ◽

Cancer Cell ◽

Cancer Cell Line ◽

Colorectal Cancer Cell Line ◽

Cervical Cancer Cell Line ◽

Synthetic Derivatives ◽

Derivatives Of

Background: Based on the structure of RC-121 (D-Phe-c (Cys-Tyr-D-Trp-Lys-Val-Cys)-Thr-NH2, - synthetic derivatives of somatostatin), some analogs were synthesized and tested for in vitro cytotoxic and antioxidant activity. Objectives: The new analogs were modifyed at position 5 with Dap (diaminopropanoic acid), Dab (diaminobutanoic acid) and Orn and at position 6 with the unnatural amino acids Tle (t-leucine). Methods: The in vitro cytotoxic effects of the substances were investigated against a panel of human tumor cell lines HT-29 (Human Colorectal Cancer Cell Line), MDA-MB-23 (Human Breast Cancer Cell Line), Hep G-2 (Human Hepatocellular Carcinoma Cell Line) and HeLa (cervical cancer cell line). The antioxidant capacities were tested by ORAC (Oxygen Radical Antioxidant Capacity) and HORAC (Hydroxyl Radical Averting Capacity) methods. Results: All substances expressed significantly higher antioxidant capacity by comparison with galic acid and Trolox. All substances showed considerable antioxidant capacity as well. Compound 2T (D-Phe-c(Cys-Tyr-DTrp- Dap-Tle-Cys)-Thr-NH2)had the highest antioxidant effect. The compound 4T (D-Phe-c(Cys-Tyr-D-Trp- Orn-Tle-Cys)-Thr-NH2) displayed antiproliferative effect on HeLa cells with IC50 30 µM. The peptide analog 3T (D-Phe-c(Cys-Tyr-D-Trp-Lys-Tle-Cys)-Thr-NH2) exerted the most pronounced inhibition on the cell vitality up to 53%, 56% and 65% resp. against MDA-MB-23, Hep G-2, HeLa in the higher tested concentration. Conclusion: The somatostatin analogs showed moderate influence on the vitality of different tumor cells and could be used in changing their pathology.

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ChemInform Abstract: Citric Acid - Its Natural and Synthetic Derivatives

ChemInform ◽

10.1002/chin.198845362 ◽

1988 ◽

Vol 19 (45) ◽

Author(s):

M. J. MILEWSKA

Keyword(s):

Citric Acid ◽

Synthetic Derivatives ◽

Natural And Synthetic

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ChemInform Abstract: SYNTHETIC DERIVATIVES AND ANALOGS OF Γ-L-GLUTAMYLTAURINE, A BIOACTIVE COMPOUND FROM BOVINE PARATHYROIDS

Chemischer Informationsdienst ◽

10.1002/chin.198506325 ◽

1985 ◽

Vol 16 (6) ◽

Author(s):

J. GULYAS ◽

A. HORVATH ◽

A. FURKA ◽

F. SEBESTYEN ◽

L. FEUER

Keyword(s):

Bioactive Compound ◽

Synthetic Derivatives

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The Buzz about ADP-Ribosylation Toxins from Paenibacillus larvae, the Causative Agent of American Foulbrood in Honey Bees

Toxins ◽

10.3390/toxins13020151 ◽

2021 ◽

Vol 13 (2) ◽

pp. 151

Author(s):

Julia Ebeling ◽

Anne Fünfhaus ◽

Elke Genersch

Keyword(s):

Virulence Factors ◽

Structural Similarity ◽

Paenibacillus Larvae ◽

American Foulbrood ◽

Rho Proteins ◽

Experimental Proof ◽

Host Interactions ◽

B Subunit ◽

Cellular Target ◽

B Subunits

The Gram-positive, spore-forming bacterium Paenibacillus larvae is the etiological agent of American Foulbrood, a highly contagious and often fatal honey bee brood disease. The species P. larvae comprises five so-called ERIC-genotypes which differ in virulence and pathogenesis strategies. In the past two decades, the identification and characterization of several P. larvae virulence factors have led to considerable progress in understanding the molecular basis of pathogen-host-interactions during P. larvae infections. Among these virulence factors are three ADP-ribosylating AB-toxins, Plx1, Plx2, and C3larvin. Plx1 is a phage-born toxin highly homologous to the pierisin-like AB-toxins expressed by the whites-and-yellows family Pieridae (Lepidoptera, Insecta) and to scabin expressed by the plant pathogen Streptomyces scabiei. These toxins ADP-ribosylate DNA and thus induce apoptosis. While the presumed cellular target of Plx1 still awaits final experimental proof, the classification of the A subunits of the binary AB-toxins Plx2 and C3larvin as typical C3-like toxins, which ADP-ribosylate Rho-proteins, has been confirmed experimentally. Normally, C3-exoenzymes do not occur together with a B subunit partner, but as single domain toxins. Interestingly, the B subunits of the two P. larvae C3-like toxins are homologous to the B-subunits of C2-like toxins with striking structural similarity to the PA-63 protomer of Bacillus anthracis.

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Small molecule induces mitochondrial fusion for neuroprotection via targeting CK2 without affecting its conventional kinase activity

Signal Transduction and Targeted Therapy ◽

10.1038/s41392-020-00447-6 ◽

2021 ◽

Vol 6 (1) ◽

Author(s):

Ke-Wu Zeng ◽

Jing-Kang Wang ◽

Li-Chao Wang ◽

Qiang Guo ◽

Ting-Ting Liu ◽

...

Keyword(s):

Small Molecule ◽

Nuclear Translocation ◽

Fusion Gene ◽

Artery Occlusion ◽

Mitochondrial Fusion ◽

Dependent Manner ◽

Behavioral Deficits ◽

Α Subunit ◽

Cellular Target ◽

Cerebral Artery Occlusion

AbstractMitochondrial fusion/fission dynamics plays a fundamental role in neuroprotection; however, there is still a severe lack of therapeutic targets for this biological process. Here, we found that the naturally derived small molecule echinacoside (ECH) significantly promotes mitochondrial fusion progression. ECH selectively binds to the previously uncharacterized casein kinase 2 (CK2) α′ subunit (CK2α′) as a direct cellular target, and genetic knockdown of CK2α′ abolishes ECH-mediated mitochondrial fusion. Mechanistically, ECH allosterically regulates CK2α′ conformation to recruit basic transcription factor 3 (BTF3) to form a binary protein complex. Then, the CK2α′/BTF3 complex facilitates β-catenin nuclear translocation to activate TCF/LEF transcription factors and stimulate transcription of the mitochondrial fusion gene Mfn2. Strikingly, in a mouse middle cerebral artery occlusion (MCAO) model, ECH administration was found to significantly improve cerebral injuries and behavioral deficits by enhancing Mfn2 expression in wild-type but not CK2α′+/− mice. Taken together, our findings reveal, for the first time, that CK2 is essential for promoting mitochondrial fusion in a Wnt/β-catenin-dependent manner and suggest that pharmacologically targeting CK2 is a promising therapeutic strategy for ischemic stroke.

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