Recent Advancements in Refashioning of NSAIDs and their Derivatives as Anticancer Candidates

Inflammation is critical to the formation and development of tumors and is closely associated with cancer. Therefore, addressing inflammation and the mediators that contribute to the inflammatory process may be a useful strategy for both cancer prevention and treatment. Tumor predisposition can be attributed to inflammation. It has been demonstrated that NSAIDs can modify the tumor microenvironment by enhancing apoptosis and chemosensitivity and reducing cell migration. There has been a recent rise in interest in drug repositioning or repurposing because the development of innovative medications is expensive, timeconsuming, and presents a considerable obstacle to drug discovery. Repurposing drugs is crucial for the quicker and less expensive development of anticancer medicines, according to an increasing amount of research. This review summarizes the antiproliferative activity of derivatives of NSAIDs such as Diclofenac, Etodolac, Celecoxib, Ibuprofen, Tolmetin, and Sulindac, published between 2017 and 2023. Their mechanism of action and structural activity relationships (SARs) were also discussed to set the path for potential future repositioning of NSAIDs for clinical deployment in the treatment of cancer.

Fused thiophene as a privileged scaffold: A review on anti-Alzheimer's disease potentials via targeting cholinesterases, monoamine oxidases, glycogen synthase kinase-3, and Aβ aggregation

As a "silent threat," Alzheimer's disease (AD) is quickly rising to the top of the list of costly and troublesome diseases facing humanity. It is growing to be one of the most troublesome and expensive conditions, with annual health care costs higher than those of cancer and comparable to those of cardiovascular disorders. One of the main pathogenic characteristics of AD is the deficiency of the neurotransmitter acetylcholine (ACh) which plays a vital role in memory, learning, and attention. Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) play a crucial role in hydrolyzing ACh. Consequently, a frequent therapy approach for AD is the suppression of AChE and BChE to improve cholinergic neurotransmission and reduce cognitive symptoms. The accumulation of amyloid plaques (Aβ) is a primary factor contributing to neurodegenerative diseases, particularly AD. Glycogen synthase kinase-3β (GSK3-β) is regarded as a pivotal player in the pathophysiology of AD since dysregulation of this kinase affects all major hallmarks of the disease, such as tau phosphorylation, Aβ aggregation, memory, neurogenesis, and synaptic function. One of the most challenging and risky issues in modern medicinal chemistry is the urgent and ongoing need for the study and development of effective therapeutic candidates for the treatment of AD. A significant class of heterocyclic molecules that can target the complex and multifactorial pathogenesis of AD are fused thiophene derivatives. The goal of the current review is to demonstrate the advancements made in fused thiophene derivatives' anti-AD activity. It also covers their mechanisms of action and studies of the structure-activity relationships in addition to the compilation of significant synthetic routes for fused thiophene derivatives with anti-AD potential. This review is intended to stimulate new ideas in the search for more rationale designs of derivatives based on fused thiophene, hoping to be more potent in treating AD.

Design, synthesis and in vitro anticancer activity of some new lomefloxacin derivatives

Our main goal was to design and synthesize novel lomefloxacin derivatives that inhibit the topoisomerase II enzyme, leading to potent anticancer activity. Lomefloxacin derivatives substituted at position 3 and 7 were synthesized and screened for cytotoxic activity utilizing 60 different human cancer cell lines. Furthermore, compounds 3a,b,c,e that revealed potent broad-spectrum anticancer activity (with mean percent GI more than 47%) were further evaluated using five dose concentrations and calculating the GI50. Compound 3e was then evaluated for cell cycle analysis and demonstrated cell cycle arrest at the G2-M phase. Moreover, the mechanism of action was determined by determining the topoisomerase inhibitory activity and the molecular modeling study. Compounds 3a,b,c,e showed broad spectrum anticancer activity. Lomefloxacin derivative 5f showed selective cytotoxic activity against melanoma SK-MEL-5 cell line. Compound 3e demonstrated comparable topoisomerase II inhibition to doxorubicin with IC50 of 0.98 µM.

The emerging role of miRNAs in epilepsy: From molecular signatures to diagnostic potential

Epilepsy is a medical condition characterized by intermittent seizures accompanied by changes in consciousness. Epilepsy significantly impairs the daily functioning and overall well-being of affected individuals. Epilepsy is a chronic neurological disorder characterized by recurrent seizures resulting from various dysfunctions in brain activity. The molecular processes underlying changes in neuronal structure, impaired apoptotic responses in neurons, and disruption of regenerative pathways in glial cells in epilepsy remain unknown. MicroRNAs (miRNAs) play a crucial role in regulating apoptosis, autophagy, oxidative stress, neuroinflammation, and the body's regenerative and immune responses. miRNAs have been shown to influence many pathogenic processes in epilepsy including inflammatory responses, neuronal necrosis and apoptosis, dendritic growth, synaptic remodeling, and other processes related to the development of epilepsy. Therefore, the purpose of our current analysis was to determine the role of miRNAs in the etiology and progression of epilepsy. Furthermore, they have been examined for their potential application as biomarkers and therapeutic targets.

Decoding the role of miRNAs in oral cancer pathogenesis: A focus on signaling pathways

Oral cancer (OC) is the predominant type originating in the head and neck region. The incidence of OC is mostly associated with behavioral risk factors, including tobacco smoking and excessive alcohol intake. Additionally, there is a lower but still significant association with viral infections such as human papillomaviruses and Epstein-Barr viruses. Furthermore, it has been observed that heritable genetic variables are linked to the risk of OC, in addition to the previously mentioned acquired risk factors. The current absence of biomarkers for OC diagnosis contributes to the frequent occurrence of advanced-stage diagnoses among patients. Non-coding RNAs (ncRNAs), including microRNAs (miRNAs), long non-coding RNAs, and circular RNAs, have been observed to exert a significant effect on the transcriptional control of target genes involved in cancer, either through direct or indirect mechanisms. miRNAs are a class of short ncRNAs that play a role in regulating gene expression by enabling mRNA degradation or translational repression at the post-transcriptional phase. miRNAs are known to play a fundamental role in the development of cancer and the regulation of oncogenic cell processes. Notch signaling, PTEN/Akt/mTOR axis, KRAS mutation, JAK/STAT signaling, P53, EGFR, and the VEGFs have all been linked to OC, and miRNAs have been shown to have a role in all of these. The dysregulation of miRNA has been identified in cases of OC and is linked with prognosis.

Topoisomerase II inhibitors design: Early studies and new perspectives

The DNA topoisomerase enzymes are widely distributed throughout all spheres of life and are necessary for cell function. Numerous antibacterial and cancer chemotherapeutic drugs target the various topoisomerase enzymes because of their roles in maintaining DNA topology during DNA replication and transcription. Agents derived from natural products, like anthracyclines, epipodophyllotoxins and quinolones, have been widely used to treat a variety of cancers. A very active field of fundamental and clinical research is the selective targeting of topoisomerase II enzymes for cancer treatment. This thematic review summarizes the recent advances in the anticancer activity of the most potent topoisomerase II inhibitors (anthracyclines, epipodophyllotoxins and fluoroquinolones) their modes of action, and structure-activity relationships (SARs) organized chronologically in the last ten years from 2013 to 2023. The review also highlights the mechanism of action and SARs of promising new topoisomerase II inhibitors.

Design, synthesis, and biological evaluation of novel ciprofloxacin derivatives as potential anticancer agents targeting topoisomerase II enzyme

A series of novel ciprofloxacin (CP) derivatives substituted at the N-4 position with biologically active moieties were designed and synthesised. 14 compounds were 1.02- to 8.66-fold more potent than doxorubicin against T-24 cancer cells. Ten compounds were 1.2- to 7.1-fold more potent than doxorubicin against PC-3 cancer cells. The most potent compounds 6, 7a, 7b, 8a, 9a, and 10c showed significant Topo II inhibitory activity (83-90% at 100 μM concentration). Compounds 6, 8a, and 10c were 1.01- to 2.32-fold more potent than doxorubicin. Compounds 6 and 8a induced apoptosis in T-24 (16.8- and 20.1-fold, respectively compared to control). This evidence was supported by an increase in the level of apoptotic caspase-3 (5.23- and 7.6-fold, sequentially). Both compounds arrested the cell cycle in the S phase in T-24 cancer cells while in PC-3 cancer cells the two compounds arrested the cell cycle in the G1 phase. Molecular docking simulations of compounds 6 and 8a into the Topo II active site rationalised their remarkable Topo II inhibitory activity.

Design, synthesis, anticancer evaluation, and molecular modelling studies of novel tolmetin derivatives as potential VEGFR-2 inhibitors and apoptosis inducers

Novel tolmetin derivatives 5a-f to 8a-c were designed, synthesised, and evaluated for antiproliferative activity by NCI (USA) against a panel of 60 tumour cell lines. The cytotoxic activity of the most active tolmetin derivatives 5b and 5c was examined against HL-60, HCT-15, and UO-31 tumour cell lines. Compound 5b was found to be the most potent derivative against HL-60, HCT-15, and UO-31 cell lines with IC50 values of 10.32 ± 0.55, 6.62 ± 0.35, and 7.69 ± 0.41 µM, respectively. Molecular modelling studies of derivative 5b towards the VEGFR-2 active site were performed. Compound 5b displayed high inhibitory activity against VEGFR-2 (IC50 = 0.20 µM). It extremely reduced the HUVECs migration potential exhibiting deeply reduced wound healing patterns after 72 h. It induced apoptosis in HCT-15 cells (52.72-fold). This evidence was supported by an increase in the level of apoptotic caspases-3, -8, and -9 by 7.808-, 1.867-, and 7.622-fold, respectively. Compound 5b arrested the cell cycle in the G0/G1 phase. Furthermore, the ADME studies showed that compound 5b possessed promising pharmacokinetic properties.

Design, synthesis and biological evaluation of novel pyrazole sulfonamide derivatives as dual COX-2/5-LOX inhibitors

The current therapeutic demand focuses more on the discovery of safer NSAIDs rather than exploring more potent alternatives. The dual COX-2/5-LOX inhibition is a promising strategy for designing compounds with an enhanced efficacy, reduced side-effects and a broader anti-inflammatory spectrum in comparison to classical NSAIDs. In the present study, a hybridization strategy was adopted to combine the binding features of the non-selective COX inhibitor "sulindac" and the selective COX-2 inhibitor "celecoxib" which show 5-LOX inhibitory activity with that of licofelone and a celecoxib pyridone analogue which show dual COX-2/5-LOX inhibitory activity to design new series of pyrazole sulfonamide derivatives which, by design, should possess dual COX-2/5-LOX inhibitory activity. All the newly synthesized compounds were initially tested for their potential analgesic activity, then candidates that showed potential analgesic activity, were selected for the subsequent anti-inflammatory activity evaluation, as well as, ulcerogenicity testing. Moreover, in vitro assessment of their COX-1, COX-2 and 5-LOX inhibitory activities were performed. The benzothiophen-2-yl pyrazole carboxylic acid derivative 5b showed the most potent analgesic and anti-inflammatory activities surpassing that of celecoxib and indomethacin. It showed potent COX-1, COX-2 and 5-LOX inhibitory activity with IC₅₀ of 5.40, 0.01 and 1.78 μM, respectively, showing a selectivity index of 344.56 that was much better than the used reference standards and its parent compounds, confirming its selectivity towards COX-2 over COX-1. The prodrug ester derivatives 6c and 6d showed equipotent activity to their parent compound 5b with no gastric ulcerogenicity. Molecular docking simulations confirmed that the newly synthesized compounds possess the structural features required for binding to the target enzymes COX-2 and 5-LOX.

Novel thienopyrimidine derivatives as dual EGFR and VEGFR-2 inhibitors: design, synthesis, anticancer activity and effect on cell cycle profile

Aim: Design and synthesis of thienopyrimidine derivatives as dual EGFR and VEGFR-2 inhibitors.Material and methods: A series of novel 6,7,8,9-tetrahydro-5H-cyclohepta[4,5]thieno[2,3-d]pyrimidine derivatives with different substituents on C-4 position was synthesized and evaluated for their anticancer activity against MCF-7 cell line. EGFR, VEGFR-2 inhibitory assay, the cell cycle analysis and apoptosis induction ability of the most potent compound 5f were evaluated.Results: Most of the compounds showed moderate to significant anticancer activity. Compound 5f exhibited the most potent anticancer activity being 1.73- and 4.64-folds more potent than erlotinib and doxorubicin, respectively. Compound 5f showed potent EGFR inhibitory activity being 1.18-folds more potent than reference standard erlotinib and it also showed good VEGFR-2 inhibitory activity at the micromolar level with IC₅₀ value 1.23 µM. Compound 5f caused induction of cell cycle arrest at G2/M phase and accumulation of cells in pre-G1 phase. Compound 5f induced cellular apoptosis.

Synthesis of Novel Thieno[2,3-d]pyrimidine Derivatives and Evaluation of Their Cytotoxicity and EGFR Inhibitory Activity

Background:

4-Substitutedaminoquinazoline scaffolds were reported to possess potent cytotoxic and EGFR inhibitory activity such as gefitinib (Iressa), erlotinib (Tarceva) and tandutinib.

Objective:

Synthesis of novel 4-substitutedaminothieno[2,3-d]pyrimidine derivatives as bioisosters of 4-substitutedaminoquinazoline derivatives with potential cytotoxic and EGFR inhibitory activity.

Methods:

Novel 4-substitutedaminothieno[2,3-d]pyrimidine derivatives 4a-i and 5a-c were synthesized via reacting corresponding 4-chlorothieno[2,3-d]pyrimidine derivatives 3a-c with N-methylpiperazine, morpholine, N-phenylpiperazine or 1,3-propanediamine. Six compounds (2a, 4d, 4e, 5a-c) were selected by the National Cancer Institute (USA) for evaluating their cytotoxic activity using 60 different human tumor cell lines using a single dose (10-5 Molar). The rest of the synthesized compounds (2b, 2c, 3a-c, 4a-c and 4f-i) were subjected to screening against T47D breast cancer cell line using a single dose (10-5 Molar) at Pharmacology lab., Cancer biology lab., Egyptian National Institute. Moreover, compounds 2a and 4b-e were subjected to further evaluation by IC50 determination. Finally, the inhibition of epidermal growth factor receptor (EGFR) was then investigated for the most active compounds 2a and 4d.

Results:

Compounds 2a and 4b-e showed significant cytotoxic activity. Compound 2a was more potent than doxorubicin against lung cancer cell line A549 with IC50 = 13.40 μM and comparable activity against MCF7. Compound 4d exhibited more potent activity than Doxorubicin against prostate PC3 (IC50 = 14.13 µM) while showed comparable activity against MCF7 and T47D.

Conclusion:

4-Substitutedaminothieno[2,3-d]pyrimidine is a promising backbone for the design and synthesis of potent cytotoxic leads.

Synthesis and Antitumour Activity of Certain Pyrido[2,3-d] Pyrimidine and 1,8-naphthyridine Derivatives

In an effort to establish new candidates with improved anticancer activity, we report here the synthesis of various series of 2,4,5,7-tetrasubstituted pyrido[2,3- d]pyrimidines and their related isosteres substituted 1,8-naphthyridines. The cytotoxic activity of the newly synthesised compounds against human breast cancer cell line, MCF7 was investigated. Most of the tested compounds exploited potent to moderate growth inhibitory activity, in particular 7-(4-chlorophenyl)-5-(3-nitrophenyl)pyrido[2,3- d]pyrimidin-4-amine exhibited superior potency to the reference drug doxorubicin (IC50 = 7.5 and 8.48 μM respectively).

Novel tacrine analogs as potential cholinesterase inhibitors in Alzheimer's disease

Acetylcholinesterase inhibitors (AChEIs) are used for the treatment of Alzheimer's disease (AD). The increase in ACh levels ameliorates the symptoms of the disease. Tacrine is the first clinically approved drug as AChEI used in the treatment of AD. In this paper, we synthesized new tacrine analogs to act on catalytic and peripheral sites of AChE. Their inhibitory activity was evaluated. All novel compounds except 7a showed promising results toward AChE. Two compounds, 10b and 11b, are more potent than tacrine. Furthermore, molecular-modeling studies were performed for these two compounds to rationalize the obtained pharmacological activity. Moreover, various drug-likeness properties of the new compounds were predicted.