Carbonic anhydrases: novel therapeutic applications for inhibitors and activators

A Multitarget Approach against Neuroinflammation: Alkyl Substituted Coumarins as Inhibitors of Enzymes Involved in Neurodegeneration

Neurodegenerative disorders (NDs) include a large range of diseases characterized by neural dysfunction with a multifactorial etiology. The most common NDs are Alzheimer's disease and Parkinson's disease, in which cholinergic and dopaminergic systems are impaired, respectively. Despite different brain regions being affected, oxidative stress and inflammation were found to be common triggers in the pathogenesis and progression of both diseases. By taking advantage of a multi-target approach, in this work we explored alkyl substituted coumarins as neuroprotective agents, capable to reduce oxidative stress and inflammation by inhibiting enzymes involved in neurodegeneration, among which are Carbonic Anhydrases (CAs), Monoamine Oxidases (MAOs), and Cholinesterases (ChEs). The compounds were synthesized and profiled against the three targeted enzymes. The binding mode of the most promising compounds (7 and 9) within MAO-A and -B was analyzed through molecular modeling studies, providing and explanation for the different selectivities observed for the MAO isoforms. In vitro biological studies using LPS-stimulated rat astrocytes showed that some compounds were able to counteract the oxidative stress-induced neuroinflammation and hamper interleukin-6 secretion, confirming the success of this multitarget approach.

Affinity-Switchable Interaction of Biotin and Streptavidin for the Signal-ON Detection of Small Molecules

Lateral flow assay (LFA) based on gold nanoparticles (AuNPs) is a widely used analytical device for the rapid analysis of environmental hazards and biomarkers. Typically, a sandwich-type format is used for macromolecule detection, in which the appearance of a red test line indicates a positive result (Signal-ON). In contrast, small molecule detection usually relies on a competitive assay, where the absence of a test line indicates positive testing (Signal-OFF). However, such a "Signal-OFF" reading is usually detected within a narrower dynamic range and tends to generate false-negative signals at a low concentration. Moreover, inconsistent readings between macromolecule and small molecule testing might lead to misinterpretation when used by nonskilled individuals. Herein, we report a "Signal-ON" small molecule competitive assay based on the sterically modulated affinity-switchable interaction of biotin and streptavidin. In the absence of a small molecule target, a large steric hindrance can be imposed on the biotin to prevent interaction with streptavidin. However, in the presence of the small molecule target, this steric effect is removed, allowing the biotin to bind to streptavidin and generate the desired test line. In this article, we demonstrate the selective detection of two small molecule drugs, sulfonamides and trimethoprim, using this simple and modular affinity-switchable lateral flow assay (ASLFA). We believe that this affinity-switchable approach can also be adapted in drug discovery and clinical diagnosis, where the competitive assay format is always used for the rapid analysis of small molecules.

Discovery of a novel series of potent carbonic anhydrase inhibitors with selective affinity for μ Opioid receptor for Safer and long-lasting analgesia

In this study, we investigated the development of dual-targeted ligands that bind to both μ-opioid receptor (MOR) and carbonic anhydrase (CA) enzymes, using fentanyl structure as a template. We synthesized and evaluated 21 novel compounds with dual-targeted affinity identifying the lead candidate compound 8, showing selective affinity for MOR and potent inhibition of several cytosolic CA isoforms. By means of repeated treatment of 3 daily administrations for 17 days, fentanyl (0.1 mg/kg, subcutaneously) led to tolerance development, pain threshold alterations and withdrawal symptoms in CD-1 mice, as well as astrocyte and microglia activation in the dorsal horn of the lumbar spinal cord. In contrast, compound 8 (0.32 mg/kg s.c.) maintained stable during days its analgesic effect at the higher dose tested with fewer withdrawal symptoms, allodynia development and glial cells activation. Our results suggest that targeting both MOR and CA enzymes can lead to the development of new class of potent analgesic agents with fewer side effects and reduced tolerance development. Further studies are needed to explore the potential mechanisms underlying these effects and to further optimize the therapeutic potential of these compounds.

Carbonic anhydrase versatility: from pH regulation to CO2 sensing and metabolism

While the carbonic anhydrase (CA, EC 4.2.1.1) superfamily of enzymes has been described primarily as involved only in pH regulation for decades, it also has many other important functions. CO2, bicarbonate, and protons, the physiological substrates of CA, are indeed the main buffering system in organisms belonging to all life kingdoms; however, in the last period, relevant progress has been made in the direction of elucidating the involvement of the eight genetically distinct CA families in chemical sensing, metabolism, and several other crucial physiological processes. Interference with CA activity, both by inhibiting and activating these enzymes, has thus led to novel applications for CA inhibitors and activators in the field of innovative biomedicine and environment and health. In this perspective article, I will discuss the recent advances which have allowed for a deeper understanding of the biochemistry of these versatile enzymes and various applications of their modulators of activity.

In vitro and in silico analysis proving DPP4 inhibition and diabetes-associated gene network modulation by a polyherbal formulation: Nisakathakadi Kashaya

Dipeptidyl-peptidase IV (DPP4) inhibitors are an important class of anti-diabetic drugs recognised for their systemic biological actions. Polyherbal preparations like Ayurveda formulations are considered to be ideal sources for discovering novel DPP4 inhibitors owing to their rich phytochemical composition. The current study reports the DPP4 inhibitory potential of a clinically established Ayurvedic anti-diabetic formulation Nisakathakadi Kashaya (NK) using in vitro assay and substantiates it by identifying potential bioactives responsible for DPP4 inhibition using computational biology tools. NK showed a dose-dependent DPP4 inhibition with an IC50 of 2.06 μg GAE/mL, and the molecular docking and simulation studies showed three compounds, namely Terchebin, Locaracemoside B and 1,2,4,6 Tetra o Galloyl Beta D Glucose having stable interactions with DPP4 similar to the standard drug Vildagliptin. Further, for the reason that polyherbal formulations exert a network pharmacology mode of action, in silico analysis was carried out to identify the other putative phytochemical-protein networks modulated by NK. The complex pharmacological network of the formulation was explored further using a subnetwork of diabetes proteins and their relationship with diabetes-associated comorbidities. A number of key targets like TNFα, TGFβ1, SOD1, SOD2, AKT1, DPP4 and GLP1R were identified in the protein-protein interaction network that is vital to diabetic progression and complications. A combination of in vitro and in silico methods allowed us to prove the DPP4 inhibition potential of NK as well as provided insights into the possible pharmacological networking through which NK potentially exerts its systemic effect in diabetes management.Communicated by Ramaswamy H. Sarma.

Discovery of indolinone-bearing benzenesulfonamides as new dual carbonic anhydrase and VEGFR-2 inhibitors possessing anticancer and pro-apoptotic properties

In the current medical era, the utilization of a single small molecule to simultaneously target two distinct molecular targets is emerging as a highly effective strategy in the battle against cancer. Carbonic Anhydrase (CA) and Vascular-Endothelial Growth Factor (VEGF) are genes that are activated in response to low oxygen levels (hypoxia) and play a role in the development and progression of tumors in hypoxic conditions. Herein we report the design, synthesis, and biological assessment of a series of novel indolinone-based benzenesulfonamides (8a-k, 11a-d, 15a-d, and 16) as potential dual inhibitors for cancer-associated hCA IX/XII and VEGFR-2. All the synthesized sulfonamides were assessed for their inhibitory effect against four CA isoforms I, II, IX, and XII where they displayed varying degrees of hCA inhibition. The most effective and selective hCA IX and XII inhibitors 8g, 8j and 15b were chosen to be tested for their in vitro inhibitory impact against VEGFR-2 as well as their antiproliferative impact against VEGFR-2 overexpressing MDA-MB-231 and MCF-7 breast cancer cells. Furthermore, molecular docking studies were conducted within the hCA IX, XII, and VEGFR-2 active sites to explain the observed inhibitory results.

Antimalarial Agents Targeting Plasmodium falciparum Carbonic Anhydrase: Towards Artesunate Hybrid Compounds with Dual Mechanism of Action

Malaria continues to be a major public health challenge worldwide and, as part of the global effort toward malaria eradication, plasmodium carbonic anhydrases (CAs) have recently been proposed as potential targets for malaria treatment. In this study, a series of eight hybrid compounds combining the Artesunate core with a sulfonamide moiety were synthesized and evaluated for their inhibition potency against the widely expressed human (h) CAs I, II and the isoform from P. falciparum (PfCA). All derivatives demonstrated high inhibition potency against PfCA, achieving a KI value in the sub-nanomolar range (0.35 nM). Two Compounds showed a selectivity index of 4.1 and 3.1, respectively, against this protozoan isoform compared to hCA II. Three Derivatives showed no cytotoxic effects on human gingival fibroblasts at 50 μM with a high killing rate against both P. falciparum and P. knowlesi strains with IC50 in the sub-nanomolar range, providing a wide therapeutic window. Our findings suggest that these compounds may serve as promising leads for developing new antimalarial drugs and warrant further investigation, including activity against antimalarial-resistant strains, mode of action studies, and in vivo efficacy assessment in preclinical mouse models of malaria.

Formation of morpholine-acetamide derivatives as potent anti-tumor drug candidates: Pharmacological evaluation and molecular docking studies

Heterocyclic amines and acetamide derivatives are known for their chemotherapeutic potential. Hence, in the present study, morpholine was taken as a principal product and novel morpholine derivatives were designed, formulated, characterized, and screened for the mechanism of inhibition of carbonic anhydrase and their anticancer potential. In addition, in vitro inhibition of hypoxia-inducible factor-1 (HIF-1) protein was also investigated. Results revealed that compounds 1c, 1d, and 1h possessed significant inhibitory activities against carbonic anhydrase with IC50 of 8.80, 11.13, and 8.12 μM, respectively. Interestingly, the carbonic anhydrase inhibitory activity of compound 1h was comparable with that of standard acetazolamide (IC50 7.51 μM). The compounds 1h and 1i significantly inhibited the proliferation of ovarian cancer cell line ID8 with IC50 of 9.40, and 11.2 μM, respectively while the standard cisplatin exhibited an IC50 8.50 μM. In addition, compounds 1c, 1b, 1h and 1i also exhibited significant inhibitory effects on HIF-1α. In conclusion, we report first time the biological potential of morpholine based compounds against ovarian cancer and HIF-1α that may serve as lead molecules for drug discovery.

Potent inhibitors of tumor associated carbonic anhydrases endowed with cathepsin B inhibition

Twenty-one novel extended analogs of acetazolamide were synthesized and screened in vitro for their inhibition efficacy against human carbonic anhydrase (hCA) isoforms I, II, IX, XII, and cathepsin B. The majority of the compounds were found to be effective inhibitors of tumor-associated hCA IX and XII, and poor inhibitors of cytosolic hCA I. Despite the strong to moderate inhibition potential possessed by these compounds toward another cytosolic isoform hCA II, some of them demonstrated better potency against hCA IX and/or XII isoforms as compared to hCA II. Four compounds (11f, 11g, 12c, and 12g) effectively inhibited hCA IX and/or XII isoforms with considerable selectivity over the off-targets hCA I and II. Interestingly, five compounds, including 11f, 11g, 12c, 12d, and 12g, inhibited hCA IX even better than the clinically used acetazolamide. Some of the novel synthesized compounds exhibited higher anti-cathepsin B potential than acetazolamide, with % inhibition of around 50%, at a concentration of 10-7  M. Further, two compounds (12g and 12c) that showed effective and selective inhibition activity profiles against hCA IX and XII were additionally found to be effective inhibitors of cathepsin B.

Ru(ii)/Os(ii)-based carbonic anhydrase inhibitors as photodynamic therapy photosensitizers for the treatment of hypoxic tumours

Photodynamic therapy (PDT) is a medical technique for the treatment of cancer. It is based on the use of non-toxic molecules, called photosensitizers (PSs), that become toxic when irradiated with light and produce reactive oxygen specious (ROS) such as singlet oxygen (1O2). This light-induced toxicity is rather selective since the physician only targets a specific area of the body, leading to minimal side effects. Yet, a strategy to improve further the selectivity of this medical technique is to confine the delivery of the PS to cancer cells only instead of spreading it randomly throughout the body prior to light irradiation. To address this problem, we present here novel sulfonamide-based monopodal and dipodal ruthenium and osmium polypyridyl complexes capable of targeting carbonic anhydrases (CAs) that are a major target in cancer therapy. CAs are overexpressed in the membrane or cytoplasm of various cancer cells. We therefore anticipated that the accumulation of our complexes in or outside the cell prior to irradiation would improve the selectivity of the PDT treatment. We show that our complexes have a high affinity for CAs, accumulate in cancer cells overexpressing CA cells and importantly kill cancer cells under both normoxic and hypoxic conditions upon irradiation at 540 nm. More importantly, Os(ii) compounds still exhibit some phototoxicity under 740 nm irradiation under normoxic conditions. To our knowledge, this is the first description of ruthenium/osmium-based PDT PSs that are CA inhibitors for the selective treatment of cancers.

Biological Effects and Crystal X-Ray Study of Novel Schiff Base Containing Pentafluorophenyl Hydrazine: In Vitro and in Silico Studies

A novel Schiff base namely 3,5-di-tert-butyl-6-((2-(perfluorophenyl)hydrazono)methyl)phenol was successfully synthesized and characterized using FT-IR and 1 H-NMR, 13 C-NMR, and 19 F-NMR. The crystal structure analysis of the Schiff base compound was also characterized with single crystal X-ray diffraction studies and supported the spectroscopic results. The cytotoxicity, anti-bacterial properties, and enzyme inhibition of the compound were also investigated. The molecular docking studies were performed in order to explain the interactions of the synthesized compound with target enzymes. The newly synthesized hydrazone derivative Schiff base compound showed high cellular toxicity on MCF-7 and PC-3 cells. Also, this compound caused low antibacterial effect on E. coli and S. aureus. Besides, the compound exhibited the inhibitory effect against pancreatic cholesterol esterase and carbonic anhydrase isoenzyme I, II with IC50 values 63, 99, and 188 μM, respectively. Consequently, it has been determined that the prepared Schiff base is an active compound in terms of cytotoxicity, enzyme inhibition, and anti-bacterial properties. These results provide preliminary information for some biological features of the compound and can play a major role in drug applications of the Schiff base compound.

Targeting carbonic anhydrases for the management of hypoxic metastatic tumors

INTRODUCTION

Several isoforms of the metalloenzyme carbonic anhydrase (CA, EC 4.2.1.1) are connected with tumorigenesis. Hypoxic tumors overexpress CA IX and XII as a consequence of HIF activation cascade, being involved in pH regulation, metabolism, and metastases formation. Other isoforms (CA I, II, III, IV) were also reported to be present in some tumors.

AREAS COVERED

Some CA isoforms are biomarkers for disease progression or response to therapy. Inhibitors, antibodies, and other procedures for targeting these enzymes for the treatment of tumors/metastases are discussed. Sulfonamides and coumarins represent the most investigated classes of inhibitors, but carboxylates, selenium, and tellurium-containing inhibitors were also investigated. Hybrid drugs of CA inhibitors with other antitumor agents for multitargeted therapy were reported.

EXPERT OPINION

Targeting CAs present in solid or hematological tumors with selective, targeted inhibitors is a validated approach, which has been consolidated in the last years. A host of new preclinical data and several clinical trials of antibodies and small-molecule inhibitors are ongoing, which connected with the large number of new chemotypes/procedures discovered to be effective, may lead to a breakthrough in this therapeutic area. The scientific/patent literature has been searched for on PubMed, ScienceDirect, Espacenet, and PatentGuru, from 2018 to 2023.

Inhibition of carbonic anhydrase using aspirin is a novel method to block schistosomiasis infection of the parasitic trematode, Schistosoma mansoni, in the intermediate snail host, Biomphalaria glabrata

Schistosomiasis is a major public health concern worldwide. Although praziquantel is currently available as the only treatment option for schistosomiasis, the absence of reliable diagnostic and prognostic tools highlights the need for the identification and characterization of new drug targets. Recently, we identified the B. glabrata homolog (accession number XP_013075832.1) of human CAXIV, showing 37% amino acid sequence identity, from a BLAST search in NCBI (National Center for Biotechnology Information). Carbonic Anhydrases (CAs) are metalloenzymes that catalyze the reversible hydration/dehydration of CO2/HCO3. These enzymes are associated with many physiological processes, and their role in tumorigenesis has been widely implicated. CAs create an acidic extracellular environment that facilitates the survival, metastasis, and growth of cancer cells. In this study, we investigated the role of CA inhibition in B. glabrata snails exposed to S. mansoni miracidia. We analyzed the expression of the B. glabrata CA encoding transcript in juvenile susceptible and resistant snails, with and without exposure to S. mansoni. Our results showed that the expression of the CA mRNA encoding transcript was upregulated during early and prolonged infection in susceptible snails (BBO2), but not in the resistant BS-90 stock. Notably, sodium salicylate, a form of aspirin, inhibited the expression of CA, post-exposure, to the parasite. Increasing research between parasites and cancer has shown that schistosomes and cancer cells share similarities in their capacity to proliferate, survive, and evade host immune mechanisms. Here, we show that this model system is a potential new avenue for understanding the role of CA in the metastasis and proliferation of cancer cells. Further studies are needed to explore the potential of CA as a biomarker for infection in other schistosomiasis-causing parasites, including S. japonicum and S. haematobium.

Design and synthesis of sulfonamides incorporating a biotin moiety: Carbonic anhydrase inhibitory effects, antiproliferative activity and molecular modeling studies

Sulfonamides constitute an important class of classical carbonic anhydrase (CA, EC 4.2.1.1) inhibitors. Herein we have accomplished the conjugation of biotin with an ample number of sulfonamide motifs with the aim of testing them in vitro as inhibitors of the human carbonic anhydrase (hCA) isoforms I and II (cytosolic isozymes), as well as hCA IX and XII (transmembrane, tumor-associated enzymes). Most of these newly synthesized compounds exhibited interesting inhibition profiles, with activities in the nanomolar range. The presence of a 4-F-C6H4 moiety, also found in SLC-0111, afforded an excellent selectivity towards the tumor-associated hypoxia-induced hCA isoform XII with an inhibition constant (KI) of 4.5 nM. The 2-naphthyl derivative was the most potent inhibitor against hCA IX (KI = 6.2 nM), 4-fold stronger than AAZ (KI = 25 nM) with very good selectivity. Some compounds were chosen for antiproliferative activity testing against a panel of 3 human tumor cell lines, one compound showing anti-proliferative activity on glioblastoma, triple-negative breast cancer, and pancreatic carcinoma cell lines.

[Acetazolamide and uveal effusion: report of two cases]

We report two cases of uveal effusion following oral acetazolamide administration: one case after a standard cataract surgery and a second following a preventive treatment for altitude sickness. The outcome in both cases was favorable. This rare complication requires appropriate management, including ruling out other pathologies. The pathophysiological mechanism is not fully understood.

[1, 8]-Naphthyridine derivatives as dual inhibitor of alkaline phosphatase and carbonic anhydrase

[1,8]-Naphthyridine derivatives have been reported to possess important biological activities and may serve as attractive pharmacophores in the drug discovery process. [1,8]-Naphthyridine derivatives (1a-1l) were evaluated for inhibitory potential for isozymes of carbonic anhydrase (CA) and alkaline phosphatase (ALP). CAs have been reported to carry out reversible hydration of CO2 into HCO3-, secretion of electrolytes, acid-base regulation, bone resorption, calcification, and biosynthetic reactions. Whereas ALPs hydrolyze monophosphate esters with the release of inorganic phosphate and play an important role in bone mineralization. Both enzymes have been found to be over-expressed and raised functional activities in patients suffering from rheumatoid arthritis. The discovery of dual inhibitors of these enzymes may provide a synergistic effect to cure bone disorders such as rheumatoid arthritis and ankylosing spondylitis. Among the test compounds, the most potent inhibitors for CA-II, CA-IX, and CA-XII were 1e, 1g, and 1a with IC50 values of 0.44 ± 0.19, 0.11 ± 0.03 and 0.32 ± 0.07 µM, respectively. [1,8]-Naphthyridine derivatives (1a-1l) were approximately 4 folds more potent than standard CA inhibitor acetazolamide. While in the case of ALPs, the most potent compounds for b-TNAP and c-IAP were 1b and 1e with IC50 values of 0.122 ± 0.06 and 0.107 ± 0.02 µM, respectively. Thus, synthesized derivatives proved to be 100 to 800 times more potent as compared to standard inhibitors of b-TNAP and c-IAP (Levamisole and L-phenyl alanine, respectively). In addition, selectivity and dual inhibition of [1,8]-Naphthyridine derivatives confer precedence over known inhibitors. Molecular docking and molecular simulation studies were also conducted in the present studies to define the type of interactions between potential inhibitors and enzyme active sites.

Identification of a carbonic anhydrase-Rubisco complex within the alpha-carboxysome

Carboxysomes are proteinaceous organelles that encapsulate key enzymes of CO2 fixation-Rubisco and carbonic anhydrase-and are the centerpiece of the bacterial CO2 concentrating mechanism (CCM). In the CCM, actively accumulated cytosolic bicarbonate diffuses into the carboxysome and is converted to CO2 by carbonic anhydrase, producing a high CO2 concentration near Rubisco and ensuring efficient carboxylation. Self-assembly of the α-carboxysome is orchestrated by the intrinsically disordered scaffolding protein, CsoS2, which interacts with both Rubisco and carboxysomal shell proteins, but it is unknown how the carbonic anhydrase, CsoSCA, is incorporated into the α-carboxysome. Here, we present the structural basis of carbonic anhydrase encapsulation into α-carboxysomes from Halothiobacillus neapolitanus. We find that CsoSCA interacts directly with Rubisco via an intrinsically disordered N-terminal domain. A 1.98 Å single-particle cryoelectron microscopy structure of Rubisco in complex with this peptide reveals that CsoSCA binding is predominantly mediated by a network of hydrogen bonds. CsoSCA's binding site overlaps with that of CsoS2, but the two proteins utilize substantially different motifs and modes of binding, revealing a plasticity of the Rubisco binding site. Our results advance the understanding of carboxysome biogenesis and highlight the importance of Rubisco, not only as an enzyme but also as a central hub for mediating assembly through protein interactions.

Enzyme inhibitory potential of some indole Schiff bases on acetylcholinesterase and human carbonic anhydrase isoforms I and II enzymes: an in vitro and molecular docking study

In this study, the in vitro effects of some indole Schiff bases on acetylcholinesterase and human carbonic anhydrase isoforms I and II were investigated. A series of N-methylindole hydrazide/hydrazone derivatives (1a-1t) were tested on these enzymes. The interactions of the synthesized indole derivatives with target enzymes were studied by molecular docking methodology. The results revealed that indole derivative Schiff base compounds inhibited the enzymes significantly. Ki values for hCAI isoenzyme were determined to be in the range of 36.18 ± 3.07-224.29 ± 5.78 nM; for the hCAII isoenzyme in the range of 31.30 ± 2.63-201.64 ± 7.25 nM; for acetylcholinesterase in the range of 6.82 ± 0.72-110.30 ± 9.26 nM. Compared to the control compound Acetazolamide (AZA), 1k and 1p were found to have the best inhibitory effect for hCAI; 1p was found to be the best inhibitory effect for hCAII. Compared to the control compound Tacrine (TAC), 1s showed the best inhibitory effect for AChE. In vitro results were verified with the results obtained by docking studies and interactions with enzymes were demonstrated.Communicated by Ramaswamy H. Sarma.

Harnessing large language models (LLMs) for candidate gene prioritization and selection

BACKGROUND

Feature selection is a critical step for translating advances afforded by systems-scale molecular profiling into actionable clinical insights. While data-driven methods are commonly utilized for selecting candidate genes, knowledge-driven methods must contend with the challenge of efficiently sifting through extensive volumes of biomedical information. This work aimed to assess the utility of large language models (LLMs) for knowledge-driven gene prioritization and selection.

METHODS

In this proof of concept, we focused on 11 blood transcriptional modules associated with an Erythroid cells signature. We evaluated four leading LLMs across multiple tasks. Next, we established a workflow leveraging LLMs. The steps consisted of: (1) Selecting one of the 11 modules; (2) Identifying functional convergences among constituent genes using the LLMs; (3) Scoring candidate genes across six criteria capturing the gene's biological and clinical relevance; (4) Prioritizing candidate genes and summarizing justifications; (5) Fact-checking justifications and identifying supporting references; (6) Selecting a top candidate gene based on validated scoring justifications; and (7) Factoring in transcriptome profiling data to finalize the selection of the top candidate gene.

RESULTS

Of the four LLMs evaluated, OpenAI's GPT-4 and Anthropic's Claude demonstrated the best performance and were chosen for the implementation of the candidate gene prioritization and selection workflow. This workflow was run in parallel for each of the 11 erythroid cell modules by participants in a data mining workshop. Module M9.2 served as an illustrative use case. The 30 candidate genes forming this module were assessed, and the top five scoring genes were identified as BCL2L1, ALAS2, SLC4A1, CA1, and FECH. Researchers carefully fact-checked the summarized scoring justifications, after which the LLMs were prompted to select a top candidate based on this information. GPT-4 initially chose BCL2L1, while Claude selected ALAS2. When transcriptional profiling data from three reference datasets were provided for additional context, GPT-4 revised its initial choice to ALAS2, whereas Claude reaffirmed its original selection for this module.

CONCLUSIONS

Taken together, our findings highlight the ability of LLMs to prioritize candidate genes with minimal human intervention. This suggests the potential of this technology to boost productivity, especially for tasks that require leveraging extensive biomedical knowledge.

PI3K/mTOR inhibitor VS-5584 combined with PLK1 inhibitor exhibits synergistic anti-cancer effects on non-small cell lung cancer

Small molecule drugs are of significant importance in the treatment of non-small cell lung cancer (NSCLC). Here, we explored biological effects of the PI3K/mTOR inhibitor VS-5584 on NSCLC. Our findings indicated that VS-5584 administration resulted in a dose-dependent inhibition of NSCLC cell proliferation, as well as the induction of apoptosis and cycle arrest. Additionally, we observed a significant increase in intracellular reactive oxygen species (ROS) levels following VS-5584 treatment. The use of the ROS inhibitor N-acetylcysteine (NAC) effectively reduced ROS levels and decreased the proportion of apoptotic cells. Treatment with VS-5584 led to an upregulation of genes associated with apoptosis and cell cycle, such as c-caspase 3 and P21. Conversely, a downregulation of cyclin-dependent kinase 1 (CDK1) expression was observed. Next, transcriptome analyses revealed that VS-5584 treatment altered the abundance of 1520 genes/transcripts in PC-9 cells, one of which was polo-like kinase 1 (PLK1). These differentially expressed genes were primarily enriched in biological processes such as cell cycle regulation and cell apoptosis, which are closely linked to the P53 and apoptosis pathways. Co-treatment with VS-5584 and PLK1 inhibitor NMS-P937 resulted in enhanced cancer cell death, exhibiting synergistic inhibitory activity. Notably, VS-5584 inhibited the growth of NSCLC in a patient-derived xenograft (PDX) mouse model without observable abnormalities in major organs. Overall, VS-5584 effectively suppressed the growth of NSCLC cells both in vitro and in vivo. VS-5584 combined with NMS-P937 exhibited a synergistic effect in inhibiting NSCLC cell growth. These findings suggest that VS-5584 has potential as a therapeutic strategy for treating NSCLC.

Potent and selective carbonic anhydrase inhibition activities of pyrazolones bearing benzenesulfonamides

This research introduces a series of fourteen 4-aryl-hydrazonopyrazolone sulfonamide derivatives, denoted as 3(a-g) and 4(a-g), which encompass various aromatic substitutions. The aim was to assess the inhibitory potential of these compounds against four significant isoforms, including the cytosolic isoforms hCA I and II, as well as the tumor-associated membrane-bound isoforms hCA IX and XII. Most of the tested compounds exhibited substantial inhibition against the tumor-associated isoform hCA IX, with Ki values spanning from 1.1 to 158.2 nM. Notably, compounds 3e and 3g showed particularly strong inhibitory activity against the tumor-associated membrane-bound isoforms, hCA IX and XII, while maintaining a high selectivity ratio over cytosolic off-target isoforms hCA I and II. This selectivity is vital due to the potential of hCA IX and hCA XII as drug targets for hypoxic tumors. In an effort to create novel analogs that exhibit enhanced carbonic anhydrase inhibitory activity and specificity, we investigated the structure-activity relationships of these compounds and provided a concise interpretation of our findings. Consequently, these compounds merit consideration for subsequent medicinal and pharmacological research, holding potential for developing novel therapeutic agents targeting specific isoforms in hypoxic tumors.

4-Cyanamido-substituted benzenesulfonamides act as dual carbonic anhydrase and cathepsin inhibitors

A set of novel N-cyano-N-substituted 4-aminobenzenesulfonamide derivatives were synthesized and investigated for their inhibitory activity against four cytosolic carbonic anhydrase (CA, EC 4.2.1.1) isoforms (hCA I, II, VII and XIII) and two cathepsins (S and B). N-alkyl/benzyl-substituted derivatives were revealed to be very potent inhibitors against brain-associated hCA VII, but inactive against both cathepsins. On the other hand, N-acyl-substituted derivatives displayed significant inhibitory activities against cathepsin S, but only moderate to poor inhibitory potency against hCA VII. Both hCA VII and cathepsin S have recently been validated as therapeutic targets in neuropathic pain. This study provided an excellent starting point for further structural optimization of this class of bifunctional compounds to enhance their inhibitory activity and selectivity against hCA VII and cathepsin S and to achieve new compounds with an attractive dual mechanism of action as anti-neuropathic agents.

A DNA-encoded chemical library based on chiral 4-amino-proline enables stereospecific isozyme-selective protein recognition

DNA-encoded chemical libraries (DELs) consist of large chemical compound collections individually linked to DNA barcodes, facilitating pooled construction and screening. However, screening campaigns often fail if the molecular arrangement of the building blocks is not conducive to an efficient interaction with a protein target. Here we postulated that the use of rigid, compact and stereo-defined central scaffolds for DEL synthesis may facilitate the discovery of very specific ligands capable of discriminating between closely related protein targets. We synthesized a DEL comprising 3,735,936 members, featuring the four stereoisomers of 4-aminopyrrolidine-2-carboxylic acid as central scaffolds. The library was screened in comparative selections against pharmaceutically relevant targets and their closely related protein isoforms. Hit validation results revealed a strong impact of stereochemistry, with large affinity differences between stereoisomers. We identified potent isozyme-selective ligands against multiple protein targets. Some of these hits, specific to tumour-associated antigens, demonstrated tumour-selective targeting in vitro and in vivo. Collectively, constructing DELs with stereo-defined elements contributed to high library productivity and ligand selectivity.

Travelling under pressure - hypoxia and shear stress in the metastatic journey

Cancer cell invasion, intravasation and survival in the bloodstream are early steps of the metastatic process, pivotal to enabling the spread of cancer to distant tissues. Circulating tumor cells (CTCs) represent a highly selected subpopulation of cancer cells that tamed these critical steps, and a better understanding of their biology and driving molecular principles may facilitate the development of novel tools to prevent metastasis. Here, we describe key research advances in this field, aiming at describing early metastasis-related processes such as collective invasion, shedding, and survival of CTCs in the bloodstream, paying particular attention to microenvironmental factors like hypoxia and mechanical stress, considered as important influencers of the metastatic journey.

Analysis of Free Circulating Messenger Ribonucleic Acids in Serum Samples from Late-Onset Spinal Muscular Atrophy Patients Using nCounter NanoString Technology

5q-related Spinal muscular atrophy (SMA) is a hereditary multi-systemic disorder leading to progressive muscle atrophy and weakness caused by the degeneration of spinal motor neurons (MNs) in the ventral horn of the spinal cord. Three SMN-enhancing drugs for SMA treatment are available. However, even if these drugs are highly effective when administrated early, several patients do not benefit sufficiently or remain non-responders, e.g., adults suffering from late-onset SMA and starting their therapy at advanced disease stages characterized by long-standing irreversible loss of MNs. Therefore, it is important to identify additional molecular targets to expand therapeutic strategies for SMA treatment and establish prognostic biomarkers related to the treatment response. Using high-throughput nCounter NanoString technology, we analyzed serum samples of late-onset SMA type 2 and type 3 patients before and six months under nusinersen treatment. Four genes (AMIGO1, CA2, CCL5, TLR2) were significantly altered in their transcript counts in the serum of patients, where differential expression patterns were dependent on SMA subtype and treatment response, assessed with outcome scales. No changes in gene expression were observed six months after nusinersen treatment, compared to healthy controls. These alterations in the transcription of four genes in SMA patients qualified those genes as potential SMN-independent therapeutic targets to complement current SMN-enhancing therapies.

Supramolecular multivalency effects enhance imine formation in aqueous medium allowing for dynamic modification of enzymatic activity

Imine formation under physiological conditions represents a challenging reaction due to the strong propensity of aldimines to be hydrolyzed. Herein we disclose the remarkable effect of supramolecular multivalency on increasing imine stability. A family of reactive aldehydes was synthesized bearing supramolecularly-active sites within their structure. The imine formation activity for such aldehydes was evaluated and compared with model aldehydes. The reaction of the best-performing species - containing two carboxylate groups-with a set of amines showed a significant decrease in imine yields as the degree of supramolecular multivalency between sidechains decreased. The reversible conjugation of amino acid derivatives and small peptides was also assayed, with excellent selectivities for the imine formation at the Nα position even in substrates containing competing sites. Preliminary results on protein bioconjugation revealed that a model enzyme could be dynamically inhibited upon reaction with the aldehyde, with its native activity being recovered by displacing the imine bonds with a suitable chemical effector (i.e., acylhydrazide).

Revealing mechanism of Methazolamide for treatment of ankylosing spondylitis based on network pharmacology and GSEA

Methazolamide is a carbonic anhydrase (CA) inhibitor with satisfactory safety. Our previous studies have demonstrated the elevation of CA1 expression and the therapeutic effect of Methazolamide in Ankylosing spondylitis (AS). In this study, we explored the pathogenic role of CA1 and the pharmacological mechanism of Methazolamide in AS through Gene Set Enrichment Analysis (GSEA) and network pharmacology. Seven out of twelve CA1 related gene sets were enriched in AS group. CA1 was core enriched in above seven gene sets involving zinc ion binding, arylesterase activity and one carbon metabolic process. Functional analysis of the candidate target genes obtained from the intersection of AS associated genes and Methazolamide target genes indicated that Methazolamide exerts therapeutic effects on AS mainly through inflammatory pathways which regulate the production of tumor necrosis factor, IL-6 and nitric oxide. PTGS2, ESR1, GSK3β, JAK2, NOS2 and CA1 were selected as therapeutic targets of Methazolamide in AS. Molecular docking and molecular dynamics simulations were performed successfully. In addition, we innovatively obtained the intersection of Gene Ontology (GO)/Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses and GSEA results, and found that 18 GO terms and 5 KEGG terms were indicated in the pharmacological mechanism of Methazolamide in AS, involving bone mineralization, angiogenesis, inflammation, and chemokine signaling pathways. Nevertheless, validation for these mechanisms is needed in vivo/vitro experiments.

Efficient Ligand Discovery Using Sulfur(VI) Fluoride Reactive Fragments

Sulfur(VI) fluorides (SFs) have emerged as valuable electrophiles for the design of "beyond-cysteine" covalent inhibitors and offer potential for expansion of the liganded proteome. Since SFs target a broad range of nucleophilic amino acids, they deliver an approach for the covalent modification of proteins without requirement for a proximal cysteine residue. Further to this, libraries of reactive fragments present an innovative approach for the discovery of ligands and tools for proteins of interest by leveraging a breadth of mass spectrometry analytical approaches. Herein, we report a screening approach that exploits the unique properties of SFs for this purpose. Libraries of SF-containing reactive fragments were synthesized, and a direct-to-biology workflow was taken to efficiently identify hit compounds for CAII and BCL6. The most promising hits were further characterized to establish the site(s) of covalent modification, modification kinetics, and target engagement in cells. Crystallography was used to gain a detailed molecular understanding of how these reactive fragments bind to their target. It is anticipated that this screening protocol can be used for the accelerated discovery of "beyond-cysteine" covalent inhibitors.

Visible light-driven photocatalysts, quantum chemical calculations, ADMET-SAR parameters, and DNA binding studies of nickel complex of sulfadiazine

A 3D-supramolecular nickel integrated Ni-SDZ complex was synthesized using sodium salt of sulfadiazine as the ligand and nickel(II) acetate as the metal salt using a condensation process and slow evaporation approach to growing the single crystal. The metal complex was characterized for its composition, functional groups, surface morphology as well as complex 3D structure, by resorting to various analytical techniques. The interacting surface and stability as well as reactivity of the complex were carried out using the DFT platform. From ADMET parameters, human Intestinal Absorbance data revealed that the compound has the potential to be well absorbed, and also Ni-SDZ complex cannot cross the blood-brain barrier (BBB). Additionally, the complex's DNA binding affinity and in-vivo and in-vitro cytotoxic studies were explored utilizing UV-Vis absorbance titration, viscosity measurements, and S. pombe cells and brine shrimp lethality tests. In visible light radiation, the Ni-SDZ complex displayed exceptional photo-degradation characteristics of approximately 70.19% within 70 min against methylene blue (MB).

Amyloid Fibrils Formed by Short Prion-Inspired Peptides Are Metalloenzymes

Enzymes typically fold into defined 3D protein structures exhibiting a high catalytic efficiency and selectivity. It has been proposed that the earliest enzymes may have arisen from the self-assembly of short peptides into supramolecular amyloid-like structures. Several artificial amyloids have been shown to display catalytic activity while offering advantages over natural enzymes in terms of modularity, flexibility, stability, and reusability. Hydrolases, especially esterases, are the most common artificial amyloid-like nanozymes with some reported to act as carbonic anhydrases (CA). Their hydrolytic activity is often dependent on the binding of metallic cofactors through a coordination triad composed of His residues in the β-strands, which mimic the arrangement found in natural metalloenzymes. Tyr residues contribute to the coordination of metal ions in the active center of metalloproteins; however, their use has been mostly neglected in the design of metal-containing amyloid-based nanozymes. We recently reported that four different polar prion-inspired heptapeptides spontaneously self-assembled into amyloid fibrils. Their sequences lack His but contain three alternate Tyr residues exposed to solvent. We combine experiments and simulations to demonstrate that the amyloid fibrils formed by these peptides can efficiently coordinate and retain different divalent metal cations, functioning as both metal scavengers and nanozymes. The metallized fibrils exhibit esterase and CA activities without the need for a histidine triad. These findings highlight the functional versatility of prion-inspired peptide assemblies and provide a new sequential context for the creation of artificial metalloenzymes. Furthermore, our data support amyloid-like structures acting as ancestral catalysts at the origin of life.

Carbonic anhydrase inhibitor-decorated semiconducting oligomer nanoparticles for active-targeting NIR-II fluorescence tumor imaging

Second near-infrared window (NIR-II) fluorescence imaging has shown great potential in the field of bioimaging. To achieve a better imaging effect, variety of NIR-II fluorescence probes have been designed and developed. Among them, semiconducting oligomers (SOs) have shown unique advantages including high photostability and quantum yield, making them promise in NIR-II fluorescence imaging. Herein, we design a SO nanoparticle (ASONi) for NIR-II fluorescence imaging of tumor. ASONi is composed of an azido-functionalized semiconducting oligomer as the NIR-II fluorescence emitter, and a benzene sulfonamide-ended DSPE-PEG (DSPE-PEG-CAi) as the stabilizer. Owing to the benzene sulfonamide groups on the surface, ASONi has the capability of targeting the carbonic anhydrase IX (CA IX) of MDA-MB-231 breast cancer cell. Compared with ASON without benzene sulfonamide groups on the surface, ASONi has a 1.4-fold higher uptake for MDA-MB-231 cells and 1.5-fold higher breast tumor accumulation after i.v. injection. The NIR-II fluorescence signal of ASONi can light the tumor up within 4 h, demonstrating its capability of active tumor targeting and NIR-II fluorescence imaging.

From Benznidazole to New Drugs: Nanotechnology Contribution in Chagas Disease

Chagas disease is a neglected tropical disease caused by the protozoan Trypanosoma cruzi. Benznidazole and nifurtimox are the two approved drugs for their treatment, but both drugs present side effects and efficacy problems, especially in the chronic phase of this disease. Therefore, new molecules have been tested with promising results aiming for strategic targeting action against T. cruzi. Several studies involve in vitro screening, but a considerable number of in vivo studies describe drug bioavailability increment, drug stability, toxicity assessment, and mainly the efficacy of new drugs and formulations. In this context, new drug delivery systems, such as nanotechnology systems, have been developed for these purposes. Some nanocarriers are able to interact with the immune system of the vertebrate host, modulating the immune response to the elimination of pathogenic microorganisms. In this overview of nanotechnology-based delivery strategies for established and new antichagasic agents, different strategies, and limitations of a wide class of nanocarriers are explored, as new perspectives in the treatment and monitoring of Chagas disease.

Substituted furan sulfonamides as carbonic anhydrase inhibitors: Synthesis, biological and in silico studies

Carbonic Anhydrases (CAs) are a large family of zinc metalloenzymes that catalyze the reversible hydration of carbon dioxide involved in several of biological processes, such as respiration, calcification, acid-base balance, bone resorption, and the formation of aqueous humor, cerebrospinal fluid, saliva, and gastric acid. They show wide diversity in tissue distribution and in their subcellular localization. Fifteen novel furyl sulfonamides were designed, synthesized and evaluated against four human isoforms: hCA I, hCA II, hCA IV and hCA IX. Compounds appeared to be very active mostly against hCAI (8) and hCA IV (11) isoforms being more potent than reference drug acetazolamide (AAZ). It should be mentioned that four compounds were more active than AAZ against hCA IX isoform, with compound 13d to be selective against hCA I (SI 70), hCA II (SI 13.5) and hCA IV (SI 20). Furthermore, docking was performed for some of these compounds on all isoforms I order to understand the possible interactions with the active site. The most active compounds showed good bioavailability and drug likeness scores.

Inherent efficacies of pyrazole-based derivatives for cancer therapy: the interface between experiment and in silico

There has been an increasing trend in the design of novel pyrazole derivatives for desired biological applications. For a cost-effective strategy, scientists have implemented various computational drug design tools to go hand in hand with experiments for the design and discovery of potentially effective pyrazole-based therapeutics. This review highlights the milestones of pyrazole-containing inhibitors and the use of molecular modeling techniques in conjunction with experimental studies to provide a view of the binding mechanism of these compounds. The review focuses on the established targets that play a key role in cancer therapy, including proteins involved in tubulin polymerization, carbonic anhydrase and tyrosine kinase. Overall, using both experimental and computational methods in drug design represents a promising approach to cancer therapy.

A simple yet multifaceted 90 years old, evergreen enzyme: Carbonic anhydrase, its inhibition and activation

Advances in the carbonic anhydrase (CA, EC 4.2.1.1) research over the last three decades are presented, with an emphasis on the deciphering of the activation mechanism, the development of isoform-selective inhibitors/ activators by the tail approach and their applications in the management of obesity, hypoxic tumors, neurological conditions, and as antiinfectives.

Ferrocene-based nitroheterocyclic sulfonylhydrazones: design, synthesis, characterization and trypanocidal properties

A series of new ferrocenyl nitroheterocyclic sulfonylhydrazones (1a-4a and 1b-2b) were prepared by the reaction between formyl (R = H) or acetyl (R = CH3) nitroheterocyclic precursors [4/5-NO2(C5H2XCOR), where X = O, S)] and ferrocenyl tosyl hydrazine [(η5-C5H5)Fe(η5-C5H4SO2-NH-NH2)]. All compounds were characterized by conventional spectroscopic techniques. In the solid state, the molecular structures of compounds 1a, 2b, and 3a were determined by single-crystal X-ray diffraction. The compounds showed an E-configuration around the C=N moiety. Evaluation of trypanocidal activity, measured in vitro against the Trypanosoma cruzi and Trypanosoma brucei strains, indicated that all organometallic tosyl hydrazones displayed activity against both parasite species with a higher level of potency toward T. brucei than T. cruzi. Moreover, the biological evaluation showed that the 5-nitroheterocyclic derivatives were more efficient trypanocidal agents than their 4-nitroheterocyclic counterparts.

Design, synthesis, and structure-activity studies of new rhodanine derivatives as carbonic anhydrase II, IX inhibitors

Rhodanine and its derivatives are an important class of heterocycles with diverse biological properties, including anticancer, antibacterial, and anti-mycobacterial activities. In the present work, four series of new Rhodanine derivatives were synthesized and evaluated for their inhibitory activity against carbonic anhydrase I, II, IX, and XII isoforms. Interestingly, the tested compounds exhibited good inhibitory activity against the cytosolic isoform human carbonic anhydrase (hCA) II and tumor-associated hCA IX. While the Rhodanine-benzylidene derivatives (3a-l) and Rhodanine-hydrazine derivatives (6a-e) are found to be selective against hCA II, the Rhodanine-N-carboxylate derivatives (8a-d) are found to be highly selective toward hCA IX. The Rhodanine-linked isoxazole and 1,2,4-oxadiazole derivatives (8ba, 8da, and 8db) exhibited inhibitory activity against hCA II and hCA IX. Among the tested compounds, 3b, 3j, 6d, and 8db were found to inhibit hCA II with Ki values of 9.8, 46.4, 7.7, and 4.7 µM, respectively. Furthermore, their mechanism of action is supported by molecular docking studies. Notably, the synthesized Rhodanine derivatives belong to a nonsulfonamide class of carbonic anhydrase inhibitors.

Synthesis of 4-hydroxy-L-proline derivatives as new non-classical inhibitors of human carbonic anhydrase II activity: an in vitro study

Carbonic anhydrase (CA) is a zinc metalloenzyme that facilitates the rapid conversion of water and carbon dioxide into proton and bicarbonate ion. CA isozymes have been broadly studied in many pathological/physiological processes. In the current research, a series of 4-hydroxy-L-proline derivatives were designed and chemically synthetized, and interaction of these carboxylic acid-based compounds with hCA II were evaluated. Results indicated that different derivatives had different potencies on hCAII inhibitory activity and among them, compounds 3 b and 3c had the lowest IC50 and Kd values than 4-hydroxy-L-proline and other derivatives and therefore had the most affinity to the hCA II enzyme. As a result, compounds 3 b and 3c were chosen for additional testing in this research. The Kinetic data demonstrated that 3 b and 3c inhibit the hCA II esterase activity in a linear competitive way, with Ki values in the low micromolar range. Fluorescence tests showed that the hCA II surface hydrophobicity is diminished in the presence of compounds 3 b and 3c, as confirmed by the decrease in ANS binding to hCA II in their presence. Docking results revealed that 3 b and 3c had more binding energy than 4-hydroxy-L-proline. Furthermore, these compounds could occupy the active site of hCA II, where they would interact with critical amino acid residues via non-covalent forces to inhibit hCA II. Overall, the strengthening of inhibitory activity and the binding power of these carboxylic acid derivatives (3 b and 3c) for the hCA II makes these compounds interesting for designing novel hCA II inhibitors.Communicated by Ramaswamy H. Sarma.

Metal-Based Photosensitizers as Inducers of Regulated Cell Death Mechanisms

Over the last few decades, various forms of regulated cell death (RCD) have been discovered and were found to improve cancer treatment. Although there are several reviews on RCD induced by photodynamic therapy (PDT), a comprehensive summary covering metal-based photosensitizers (PSs) as RCD inducers has not yet been presented. In this review, we systematically summarize the works on metal-based PSs that induce different types of RCD, including ferroptosis, immunogenic cell death (ICD), and pyroptosis. The characteristics and mechanisms of each RCD are explained. At the end of each section, a summary of the reported commonalities between different metal-based PSs inducing the same RCD is emphasized, and future perspectives on metal-based PSs inducing novel forms of RCD are discussed at the end of the review. Considering the essential roles of metal-based PSs and RCD in cancer therapy, we hope that this review will provide the stage for future advances in metal-based PSs as RCD inducers.

Surface Functionalization of Gold Nanoparticles for Targeting the Tumor Microenvironment to Improve Antitumor Efficiency

Gold nanoparticles (AuNPs) have undergone significant research for their use in the treatment of cancer. Numerous researchers have established their potent antitumor properties, which have greatly impacted the treatment of cancer. AuNPs have been used in four primary anticancer treatment modalities, namely radiation, photothermal therapy, photodynamic therapy, and chemotherapy. However, the ability of AuNPs to destroy cancer is lacking and can even harm healthy cells without the right direction to transport them to the tumor microenvironment. Consequently, a suitable targeting technique is needed. Based on the distinct features of the human tumor microenvironment, this review discusses four different targeting strategies that target the four key features of the tumor microenvironment, including abnormal vasculature, overexpression of specific receptors, an acidic microenvironment, and a hypoxic microenvironment, to direct surface-functionalized AuNPs to the tumor microenvironment and increase antitumor efficacies. In addition, some current completed or ongoing clinical trials of AuNPs will also be discussed below to further reinforce the concept of using AuNPs in anticancer therapy.

Inhibition Profiles of Some Novel Sulfonamide-Incorporated α-Aminophosphonates on Human Carbonic Anhydrases

A series of hitherto unknown sulfonamide-incorporated α-aminophosphonate derivatives were synthesized through the one-pot, two-step FeCl3-catalyzed coupling of 4-aminobenzenesulfonamide with the appropriate benzaldehydes and diethyl phosphite. The new sulfonamides inhibition studies were performed on four carbonic anhydrase isoforms, i.e., the cytosolic human (h) hCA I and II (off-targets) as well as transmembrane cancer-related hCA IX and XII (targets). Among the synthesized compounds, derivative 23 resulted in the most selective compound against both cancer-associated isoforms over the off-target hCA I (hCA I/IX = 78; hCA I/XII = 458) and hCA II (hCA II/IX = 10; hCA II/XII = 56) and the binding mode of both enantiomers R and S was investigated in silico.

1,5-Diaryl-1,2,4-triazole Ureas as New SLC-0111 Analogues Endowed with Dual Carbonic Anhydrase and VEGFR-2 Inhibitory Activities

Presently, dual targeting by a single small molecule stands out as an effective cancer-fighting weapon. Carbonic anhydrase (CA) and vascular-endothelial growth factor (VEGF) are hypoxia-activatable genes that are implicated in tumorigenesis and progression of hypoxic tumors at different levels. Herein, we designed and synthesized 30 1,5-diaryl-1,2,4-triazole-tethered sulfonamides (11a-f, 12a-l, 13a-f, 15a-f) as novel SLC-0111 analogues with dual CA IX/XII and VEGFR-2 inhibitory activities. The 4-fluorophenyl SLC-0111 tail was replaced by substituted 1,5-diaryl-1,2,4-triazoles. Changing the sulfamoyl motif position provided regioisomers 11a-f and 12a-l. Elongation of the ureido linker yielded derivatives 15a-f. Inhibitory evaluations included a panel of hCAs (hCA I, II, IX, and XII) and screening against 60 cancer cell lines. Promising candidates were assessed for VEGFR-2 inhibition and selectivity and further evaluated on breast cancer cell lines (MCF-7 and T-47D) and the non-tumorigenic (MCF-10A) cells. Molecular docking studies explored the binding modes of the sulfonamides against hCA IX/XII and VEGFR-2 kinase.

Repurposing of World-Approved Drugs for Potential Inhibition against Human Carbonic Anhydrase I: A Computational Study

Human carbonic anhydrases (hCAs) have enzymatic activities for reversible hydration of CO2 and are acknowledged as promising targets for the treatment of various diseases. Using molecular docking and molecular dynamics simulation approaches, we hit three compounds of methyl 4-chloranyl-2-(phenylsulfonyl)-5-sulfamoyl-benzoate (84Z for short), cyclothiazide, and 2,3,5,6-tetrafluoro-4-piperidin-1-ylbenzenesulfonamide (3UG for short) from the existing hCA I inhibitors and word-approved drugs. As a Zn2+-dependent metallo-enzyme, the influence of Zn2+ ion models on the stability of metal-binding sites during MD simulations was addressed as well. MM-PBSA analysis predicted a strong binding affinity of -18, -16, and -14 kcal/mol, respectively, for these compounds, and identified key protein residues for binding. The sulfonamide moiety bound to the Zn2+ ion appeared as an essential component of hCA I inhibitors. Vina software predicted a relatively large (unreasonable) Zn2+-sulfonamide distance, although the relative binding strength was reproduced with good accuracy. The selected compounds displayed potent inhibition against other hCA isoforms of II, XIII, and XIV. This work is valuable for molecular modeling of hCAs and further design of potent inhibitors.

Stereoselective Solvolysis in the Synthesis of Dorzolamide Intermediates

The key intermediate in the synthesis of dorzolamide, (4S,6S)-methyl-5,6-dihydro-4H-thieno[2,3-b]thiopyran-4-ol-7,7-dioxide, can be obtained in the diastereoisomerically pure form in two straightforward steps starting from diastereoisomeric mixtures of cis/trans-(6S)-6-methyl-5,6-dihydro-4H-thieno[2,3-b]thiopyran-4-yl acetate, regardless of their ratio. The reaction of crucial importance in this scheme is a remarkably stereoselective solvolysis of the acetate ester in an acetone/phosphate buffer mixture as the solvent system. Investigation of this so far unrecognized stereoselective reaction reveals that it proceeds via an SN1-like pathway as indicated by the correlation of the solvolysis rate constants with the YOTs values of different solvent mixtures and by trapping of the reaction intermediate with sodium azide. The structure of (4S,6S)-methyl-5,6-dihydro-4H-thieno[2,3-b]thiopyran-4-ol-7,7-dioxide was confirmed by single-crystal X-ray analysis.

Tail-approach based design, synthesis, and cytotoxic evaluation of novel disubstituted and trisubstituted 1,3-thiazole benzenesulfonamide derivatives with suggested carbonic anhydrase IX inhibition mechanism

A novel series of 2,4,5- and 2,3,4-trisubstituted thiazole hybrids with 1,3,4-thiadiazolylbenzenesulfonamide was designed following the tail approach as possible hCAIX inhibitors. The key intermediate 1 was condensed with thiosemicarbazide 2a to give 1,3,4-thiadiazolylthiosemicarbazone 3, which upon hetero-cyclization with substituted α-haloketones and esters afforded 2,4,5-trisubstituted thiazole-1,3,4-thiadiazole conjugates 4-8. Furthermore, the trisubstituted thiazole-1,3,4-thiadiazole hybrids 12a-d were synthesized via the regioselective cyclization of 4-substituted-1,3,4-thiadiazolylthiosemicarbazones with phenacyl bromide. The cyclized 2,4-disubstituted thiazole 4 enhanced cytotoxicity by nine, four and two times against HepG-2, Caco2, and MCF-7, respectively. Moreover, the simple methyl substitution on the thiosemicarbazone terminus 9a improved the parent derivative 3 cytotoxicity by nine, fourteen, and six times against HepG-2, Caco2, and MCF-7, respectively. This astonishing cytotoxicity was elaborated with hCAIX molecular docking simulation of 4, 9a, and 12d demonstrating binding to zinc and its catalytic His94. Furthermore, molecular dynamic simulation 9a revealed stable hydrogen bonding with hCAIX with interaction energy of -61.07 kcal mol-1 and ΔGbinding MM-PBSA of -9.6 kcal mol-1.

Synthesis and Characterization of Novel 1,3-Diaryltriazene-Substituted Sulfaguanidine Derivatives as Selective Carbonic Anhydrase Inhibitors: Biological Evaluation, in Silico ADME/T and Molecular Docking Study

Sulfonamide compounds known as human carbonic anhydrase (hCA) inhibitors are used in the treatment of many diseases such as epilepsy, antibacterial, glaucoma, various diseases. 1,3-diaryl-substituted triazenes and sulfaguanidine are used for therapeutic purposes in many drug structures. Based on these two groups, the synthesis of new compounds is important. In the present study, the novel 1,3-diaryltriazene-substituted sulfaguanidine derivatives (SG1-13) were synthesized and fully characterized by spectroscopic and analytic methods. Inhibitory effect of these compounds on the hCA I and hCA II was screened as in vitro. All the series of synthesized compounds have been identified as potential hCA isoenzymes inhibitory with KI values in the range of 6.44±0.74-86.85±7.01 nM for hCA I and with KI values in the range of 8.16±0.40-77.29±9.56 nM for hCA II. Moreover, the new series of compounds showed a more effective inhibition effect than the acetazolamide used as a reference. The possible binding positions of the compounds with a binding affinity to the hCA I and hCA II was demonstrated by in silico studies. In conclusion, compounds with varying degrees of affinity for hCA isoenzymes have been designed and as selective hCA inhibitors. These compounds may be potential alternative agents that can be used to treat or prevent diseases associated with glaucoma and hCA inhibition.

Carbonic anhydrase IX subcellular localization in normoxic and hypoxic SH-SY5Y neuroblastoma cells is assisted by its C-terminal protein interaction domain

The human carbonic anhydrase IX (CA IX) is a hypoxia-induced transmembrane protein belonging to the α-CA enzyme family. It has a crucial role in pH regulation in hypoxic cells and acts by buffering intracellular acidosis induced by hypoxia. Indeed, it is frequently expressed in cancer cells, where it contributes to tumor progression. CA IX is also able to localize in the nucleus, where it contributes to 47S rRNA precursor genes transcription; however, the mechanisms assisting its nuclear translocation still remain unclear. The aim of our study was to deepen the understanding of the mechanisms involved in CA IX subcellular distribution. To this purpose, we implemented a site-directed mutagenesis approach targeting the C-terminal domain of CA IX and evaluated the subcellular distribution of the wild-type and mutant proteins in the SH-SY5Y cell line. The mutant proteins showed impaired binding ability and altered subcellular distribution in both normoxic and hypoxic conditions. Our data suggest that CA IX nuclear translocation depends on its transit through the secretory and the endocytic pathways.

Novel bis-ureido-substituted sulfaguanidines and sulfisoxazoles as carbonic anhydrase and acetylcholinesterase inhibitors

To discover alternative substances to compounds used to treat many diseases, especially treating Alzheimer's disease (AD) and Parkinson's disease targeting carbonic anhydrase (hCA) and acetylcholinesterase (AChE) enzymes, is important. For this purpose, a series of novel bis-ureido-substituted sulfaguanidine (SG1-4) and sulfisoxazole (SO1-4) derivatives were synthesized, and their inhibitory capacities were screened against hCA isoenzymes (hCA I and II) and AChE. Possible binding mechanisms of inhibitors to the active site were elucidated by in silico studies, and the results were supported by in vitro results. Moreover, the percent radical scavenging capacities of the derivatives were also evaluated. The derivatives (SG1-4 and SO1-4) were more effective against hCAs compared to standard drug acetazolamide (KI values of 98.28-439.17 nM for hCA I and II, respectively) and exhibited the highest inhibition with the KIs in the ranges of 2.54 ± 0.50-41.02 ± 7.52 nM for hCA I, 11.20 ± 2.97-67.14 ± 13.58 nM for hCA II, and 257.60 ± 27.84-442.60 ± 52.13 nM for AChE. Also, compounds SG1 and SO1 also showed ABTS radical scavenging activity at the rate of 70% and 78%, respectively. These results will contribute to the literature for the rational design and synthesis of new potent and selective inhibitors targeting hCAs and AChE with multifunctional effects such as radical scavenging as well as inhibition. This study focused on the synthesis and inhibitory effects of bis-ureido-substituted sulfaguanidine (SG1-4) and sulfisoxazole (SO1-4) derivatives against human hCA I and II isoforms and AChE. In order to test synthesized derivatives' free radical scavenging potentials were the DPPH and ABTS assays. In silico studies elucidated possible binding mechanisms of inhibitors to the active site.

CA9 knockdown enhanced ionizing radiation-induced ferroptosis and radiosensitivity of hypoxic glioma cells

PURPOSE

Ferroptosis is a type of regulatory cell death, caused by excessive lipid peroxidation This study aimed to explore whether ionizing radiation could induce ferroptosis in glioma cells and whether carbonic anhydrase 9 (CA9) knockdown could enhance the killing effect of ionizing radiation on hypoxic glioma cells through ferroptosis.

MATERIALS AND METHODS

The protein levels of Acyl-CoA Synthetase Long Chain Family Member 4 (ACSL4) were detected by Western blot in glioma cells irradiated by different doses of X-ray. The relative mRNA levels of ferroptosis markers and intracellular iron-associated proteins were detected by Real-time qPCR. Lipid peroxidation of glioma cells was detected by oxidation-sensitive probe C11-BODIPY581/591 staining. CCK-8 Assay was used to detect cell viability after X-ray irradiation. Cloning formation assay was used to assess the radiosensitivity of glioma cells. The exposure of cell surface calreticulin was measured by immunofluorescence staining.

RESULTS

X-ray induced lipid peroxidation and ferroptosis markers expression in U251 and GL261 glioma cells. Knockdown of CA9 in hypoxic glioma cells significantly altered the expression of iron regulation-related proteins and enhanced X-ray-induced ferroptosis and radiosensitivity. The ferroptosis inhibitor significantly improved the survival of cells irradiated by X-ray, while ferroptosis inducers (FINs) enhanced the lethal effect of X-ray on cells. Enhancing ferroptosis in glioma cells promoted the exposure and release of damage-associated molecular patterns (DAMPs).

CONCLUSIONS

Ionizing radiation can induce ferroptosis in glioma cells. CA9 knockdown can enhance the radiosensitivity of hypoxic glioma cells and overcome the resistance of ferroptosis under hypoxia. Enhancing ferroptosis will become a new idea to improve the efficacy of radiotherapy for glioma.