Human Cell Line HeLa Research Articles

HLTF/SERPINE1 Axis Plays a Crucial Pro-Oncogenic Role in the Progression from Cervical Precancerous Lesions to Cervical Carcinoma in vitro

Objectives: Cervical carcinoma (CC) is prevalent among women worldwide with increasing risk. Finding effective methods for treating CC is of utmost importance. The aim of this study was to investigate the effect of SERPINE1 on the progression of cervical precancerous lesions to CC. Design: This study used transcriptome sequencing and in vitro cell line. Participants/Materials: Cervical precancerous lesions and CC samples and human cervical epithelial immortalized cell line H8, human CC cell lines HeLa, and CaSki were involved in this study. Setting and Methods: Next-generation sequencing was applied to identify 100 differentially expressed genes from cervical precancerous lesions and CC samples. With the application of the Search Tool for the Retrieval of Interacting Genes (STRING) database, we carried out the protein-protein interaction network analysis, thus screening out serine protease inhibitor clade E member 1 (SERPINE1) with significant upregulation in CC cells. The helicase-like transcription factor (HLTF) was predicted as the upstream transcription factor using Human Transcription Factor Database (HumanTFDB). The chromatin immunoprecipitation (ChIP) experiment was conducted to validate the interaction between SERPINE1 and HLTF. The immunohistochemistry was employed to determine the expression of SERPINE1 and HLTF in CC tissues. Following the upregulation or downregulation of SERPINE1 and HLTF, the real-time quantitative reverse transcription polymerase chain reaction was carried out to assess mRNA expression levels of SERPINE1 and HLTF in cells. Cell viability, migration, and invasion were evaluated using MTT assay, cell scratch assay, and Transwell assay, respectively. Western blot analysis was conducted to assess changes in the expression levels of matrix metalloproteinases and proteins related to epithelial-mesenchymal transition (EMT). Results: The ChIP experiment confirmed the interaction between HLTF and SERPINE1. HLTF and SERPINE1 were upregulated in CC tissues and cells, and silencing SERPINE1 inhibited the EMT process and viability, migration, and invasion of CC cells. However, overexpression of SERPINE1 in CC cells showed the opposite trend. Rescue experiments demonstrated that silencing HLTF repressed CC cell viability, migration, and invasion, which could be restored by overexpressing SERPINE1. Limitations: The effect of the HLTF/SERPINE1 axis on CC malignant progression has not been confirmed by in vivo experiments. Conclusion: HLTF transcriptionally activates SERPINE1, promoting the progression from cervical precancerous lesions to CC.

Acylfulvenes covalently interact with thioredoxin as an additional cancer target

Maintaining cellular redox homeostasis is critical for cell viability and growth, with disruptions implicated in cellular responses to chemicals and drugs. This study investigates the interactions between acylfulvenes (AFs), a class of DNA alkylating drugs, and thioredoxin (Trx), a key redox regulating enzyme. AFs are semi-synthetic derivatives of the natural product illudin S. While their cytotoxic properties are widely attributed to DNA alkylation, they also react with cellular thiols, such as Trx, and the implications of these interactions remain poorly understood. Through biochemical assays with isolated E. Coli Trx, and cellular experiments in a human cell line (HeLa), we elucidate AFs’ impact on Trx activity and cellular levels. AFs, particularly hydroxymethylacylfulvene (HMAF), inhibited Trx activity by covalently modifying its active site cysteines. Drug exposure also altered cellular Trx levels and nuclear accumulation. In contrast, illudin S, which has a less selective toxicity profile for cancer cells, minimally inhibited isolated Trx. These data underscore Trx as a potential target contributing to the chemotherapeutic potential of AFs and provide insights into molecular interactions governing their impact on cancer cells.

Aromatic Polymethacrylates from Lignin-Based Feedstock: Synthesis, Thermal Properties, Life-Cycle Assessment and Toxicity.

There is currently a great need for rigid, high-performance and processable bio-based polymers and plastics as alternatives to the fossil-based materials used today. Here, we report on the straightforward synthesis and polymerization of lignin-derived methacrylate monomers based on the methyl esters of syringic, vanillic, and 4-hydroxybenzoic acid, respectively. The corresponding homopolymethacrylates exhibit high glass transition temperatures (Tgs) at 106, 128, and 197°C, respectively. Rheological properties and thermal stability up to at least 277 °C indicate that these polymers are melt-processable. In addition, copolymers with methyl methacrylate are prepared to further vary and tune the polymer properties. An integrated ex-ante and prospective life-cycle assessment of key environmental impact parameters indicates similar or only slightly higher values compared to well-established fossil-based methyl methacrylate. Moreover, the toxicity towards human HeLa cell lines compares well with that of poly(methyl methacrylate). Hence, the potential availability of lignin-derived acids, combined with the straightforward and potentially upscalable monomer synthesis, make these rigid polymers appealing alternatives towards bio-based high-Tgthermoplastic materials with low toxicity.

Cell Cycle Modulation through Physical Confinement in Micrometer-Thick Hydrogel Sheaths.

Recently, surface engineering of the cell membrane with biomaterials has attracted great attention for various biomedical applications. In this study, we investigated the possibility of modulating cell cycle progression using alginate and gelatin-based hydrogel sheaths with a thickness of ∼1 μm. The hydrogel sheath was formed on cell surfaces through cross-linking catalyzed by horseradish peroxidase immobilized on the cell surface. The hydrogel sheath did not decrease the viability (>95% during 2 days of culture) of the human cervical carcinoma cell line (HeLa) expressing the fluorescent ubiquitination-based cell cycle indicator 2 (HeLa/Fucci2). Coating the HeLa/Fucci2 cells with the hydrogel sheath resulted in a cell cycle arrest in the G2/M phase, which can be caused by the reduced F-actin formation. As a result of this cell cycle arrest, an inhibition of cell growth was observed in the HeLa/Fucci2 cells. Taken together, our results demonstrate that the hydrogel sheath coating on the cell surface is a feasible approach to modulating cell cycle progression.

Amino acid deprivation in cancer cells with compensatory autophagy induction increases sensitivity to autophagy inhibitors

ABSTRACT Inhibition of autophagy is an important strategy in cancer therapy. However, prolonged inhibition of certain autophagies in established cancer cells may increase therapeutic resistance, though the underlying mechanisms of its induction and enhancement remain unclear. This study sought to elucidate the mechanisms of therapeutic resistance through repeated autophagy inhibition and amino acid deprivation (AD) in an in vitro model of in vivo chronic nutrient deprivation associated with cancer cell treatment. In the human cervical cancer cell line HeLa and human breast cancer cell line MCF-7, initial extracellular AD induced the immediate expression of endosomal microautophagy (eMI). However, repeated inhibition of eMI with U18666A and extracellular AD induced macroautophagy (MA) to compensate for reduced eMI, simultaneously decreasing cytotoxicity. Here, hyperphosphorylated JNK was transformed into a hypophosphorylated state, suggesting conversion of the cell death signal to a survival signal. In a nutrient medium, cell death could not be induced by MA inhibition. However, since LAT1 inhibitors induce intracellular AD, combining them with MA and eMI inhibitors successfully promoted cell death in resistant cells. Our study identified a novel therapeuic approach for promoting cell death and addressing therapeutic resistance in cancers under autophagy-inhibitor treatment.

Two-Dimensional Cu-Based MOF for Selective Staining of the Cellular Nucleus through Fluorescence Imaging and Selective Sorption of Dye Molecules in Aqueous Medium.

A two-dimensional copper-based metal-organic framework, [Cu(C23H14O6)(C10H8N2)2]·H2O·DMSO, 1, was synthesized using pamoic acid (C23H16O6) and 4,4'-bipyridine (C10H8N2) as an organic ligand and Cu(II) as a metal ion. Single-crystal structure X-ray diffraction studies of the as-synthesized compound showed a two- dimensional structure with free hydroxyl groups. Upon excitation at 370 nm, the aqueous dispersion of [Cu(C23H14O6)(C10H8N2)2]·H2O·DMSO, 1, showed emission centered at 525 nm resulting from the intraligand energy transfer. Fluorescence microscopic experiments using a human epithelioid cervix carcinoma HeLa cell line were carried out, clearly showing that our compound selectively stained the cellular nucleus. To utilize the porous nature of [Cu(C23H14O6)(C10H8N2)2]·H2O·DMSO, 1, its dye sorption behavior in aqueous solution was determined, and a high affinity for methylene blue (MB) dye was confirmed. Our synthesized compound sorbed 88% MB dye with an initial concentration of 32 mg L-1, and its sorption capacity for MB was found to be 29.79 mg g-1. The possible mechanism of the dye sorption behavior was discussed in terms of the size and charge of dye molecules with respect to molecular-level interactions between the framework and the dye molecules.

Formation of amygdalin/β-cyclodextrin derivatives inclusion complexes for anticancer activity assessment in human cervical carcinoma HeLa cell line

Nanoencapsulation has gained considerable attention because of its unique features and advantages in anticancer drug delivery. Amygdalin (AMY) is an anticancer compound, showing limitations in its applications by low stability. Herein, the inclusion complexes (ICs) of AMY with β-cyclodextrin (βCD), and its derivatives such as 2-hydroxypropyl-βCD (HPβCD) and methyl-βCD (MβCD) were fabricated. The fabricated AMY/CD-ICs were thoroughly evaluated using Fourier-transform infrared spectroscopy, powder X-ray diffraction, thermogravimetric/differential thermal analysis, proton nuclear magnetic resonance, ultraviolet–visible diffuse reflectance spectroscopy, and photoluminescence techniques. Double reciprocal profile study of the absorption and fluorescence spectra revealed that the AMY formed the ICs with βCD derivatives at a guest/host stoichiometric ratio of 1/1. The thermal stability of AMY was enhanced as the IC formation aid observed by the shift of thermal degradation temperature of AMY from the range of ∼ 220–250 °C to > 295 °C. Theoretical analyses of the energetic, electronic, and global reactivity parameters of the AMY/CD-ICs were evaluated using the PM3 method. Further assessment of the dissolution diagrams of AMY/CD-ICs revealed a burst release profile. In addition, cell toxicity was evaluated using the MTT assay, and the results showed that AMY/CD-ICs had significantly more efficacious in inhibiting HeLa cancer cells than AMY. These results proved that the IC formations with CDs significantly enhanced the anticancer activity of AMY.

Folic acid-mediated enhancement of the diagnostic potential of luminescent europium-doped hydroxyapatite nanocrystals for cancer biomaging

Early and accurate cancer diagnosis is crucial for improving patient survival rates. Luminescent nanoparticles have emerged as a promising tool in fluorescence bioimaging for cancer diagnosis. To enhance diagnostic accuracy, ligands promoting endocytosis into cancer cells are commonly incorporated onto nanoparticle surfaces. Folic acid (FA) is one such ligand, known to specifically bind to folate receptors (FR) overexpressed in various cancer cells such as cervical and ovarian carcinoma. Therefore, surface modification of luminescent nanoparticles with FA can enhance both luminescence efficiency and diagnostic accuracy. In this study, luminescent europium-doped hydroxyapatite (EuHAp) nanocrystals were prepared via hydrothermal method and subsequently modified with (3-Aminopropyl)triethoxysilane (APTES) followed by FA to target FR-positive human cervical adenocarcinoma cell line (HeLa) cells. The sequential grafting of APTES and then FA formed a robust covalent linkage between the nanocrystals and FA. Rod-shaped FA-modified EuHAp nanocrystals, approximately 100 nm in size, exhibited emission peaks at 589, 615, and 650 nm upon excitation at 397 nm. Despite a reduction in photoluminescence intensity following FA modification, fluorescence microscopy revealed a remarkable 120-fold increase in intensity compared to unmodified EuHAp, attributed to the enhanced uptake of FA-modified EuHAp. Additionally, confocal microscope observations confirmed the specificity and the internalization of FA-modified EuHAp nanocrystals in HeLa cells. In conclusion, the modification of EuHAp nanocrystals with FA presents a promising strategy to enhance the diagnostic potential of cancer bioimaging probes.

Isolation and structure determination of a new bisabolane-type sesquiterpenoid with cytotoxicity from Penicillium oxalicum MZY-202312-521

Endophytic fungi can produce attractive secondary metabolites with various biological activities that have contributed significantly to pharmacotherapy. In this study, three bisabolane-type sesquiterpenoids, including a new one, namely, inonotic acid C (1), together with previously reported compounds (S)-(+)-11-dehydrosydonic acid (2) and sydonic acid (3), were isolated from a marine algal-derived endophytic fungus Penicillium oxalicum MZY-202312-521. Their structures were determined by means of extensive spectroscopic analyses. The absolute configurations of inonotic acid C (1) were established by single-crystal X-ray diffraction method. In vitro cytotoxic experiments on human A549, MCF-7, HeLa, and HepG2 carcinoma cell lines were carried out. The new compound inonotic acid C (1) was found to possess strong inhibitory activity against the MCF-7 cell line, with an IC50 value of 7.7 μM.

Chemoreactome screening of aquacobalamin and heptamethyl ester of cyanoaquacobyrinic acid cytotoxic effects on tumor cells with experimental confirmation on BT-474 and A549 cell

Background. The search for an effective and safe pharmacotherapy for tumor diseases includes the evaluation of the action of candidate molecules on various types of tumor cells. Vitamin B12 and its derivatives are promising molecules whose properties can be controlled through chemical modifications.Objective: conducting in silico chemoreactom screening and in vitro experimental study of aquacobalamin and heptamethyl ester of cyanoaquacobyrinic acid (HECСA).Material and methods. Chemoreactome screening was carried out on the basis of a problem-oriented theory of chemograph isomorphism analysis, which is an extension of the algebraic approach to machine learning and recognition problems. Trainable algorithms for calculating chemical distances between molecules were used, on the basis of which the values of half-maximal inhibitory concentration (IC50) were calculated. Screening was carried out for 470 cultures of human tumor cells, including SNB19 (astrocytoma), HCT116 (colon cancer), HeLa (cervical carcinoma), BT-474 (breast duct carcinoma), and A549 (lung carcinoma) cell lines. Dicyanocobyric acid heptamethyl ester ((CN)2Cby(OCH3)7) was obtained by boiling a solution of vitamin B12 in methanol with sulfuric acid (1.0 M) for 4 days. HECСA ((CN)(H2O)Cby(OCH3)7) was obtained by vacuum drying an aqueous solution of (CN)2Cby(OCH3)7 (pH 4.0 and 25 °С). The ester structure and purity were confirmed by 1H nuclear magnetic resonance data, elemental analysis, and MALDI-ToF (matrix-assisted laser desorption/ionization time of flight) mass spectroscopy. Experimental studies of tumor cell cultures were carried out using the MTT testwith aquacobalamin and HECСA on cell lines of immortalized (telomerized) fibroblasts (Fb-hTERT), lung carcinoma (A549), and breast duct cancer (BT-474).Results. Chemoreactome screening of the effects of molecules on tumor cells made it possible to obtain estimates of cell growth IC50 for 470 tumor cell lines. Depending on cell line and vitamin B12 derivative molecule, IC50 values varied in a fairly wide range: from 15 to 2000 nM. In vitro studies on cultures of two human tumor cell lines (BT-474 and A549) and telomerized Fb-hTERT fibroblasts confirmed the cytotoxic effect of aquacobalamin and its hydrophobic derivative HECСA. It was shown that aquacobalamin had weak cytotoxic properties in the concentration range of 3.125–200 µg/l (IC50 > 200 nM), and HECСA significantly reduces the survival of BT-474 and A549 tumor cell lines at high concentrations (100–200 µg/l, IC50 about 100 nM).Conclusion. Correspondence was shown between the results of in silico chemoreactome screening and in vitro cell culture studies: IC50 values for HECСA were significantly lower than for aquacobalamin, and the conversion factor from chemoreactome estimates to experimental ones was almost the same (2.64 for BT-474, and 2.63 for A549). The results of chemoreactome screening for other tumor cell lines can be used to plan further cell experiments with vitamin B12 derivatives.

Antibacterial activity, cytotoxicity and chemotaxonomic significance of chemical constituents from Alsophila manniana Hook R.M.Tryon (Cyatheaceae) rhizomes

Phytochemical investigation of Alsophila manniana rhizomes led to the isolation of twelve known compounds, including two triterpenes (1 and 2), four steroids (3–6), one glycerol (7), three phenols (8–10), and two flavonoids (11 and 12). Their structures were elucidated by analyses of the NMR and MS data and by comparisons with those in the literature. Their antibacterial and cytotoxic activities were evaluated against Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, and Bacillus subtilis; and on human lung A549, cervical HeLa, and breast MCF-7 cancer cell lines, respectively. Fractions FD and FF had significant activities against E. coli (MIC = 75 μg/mL) and K. pneumoniae (MICs = 75 and 37.5 μg/mL). Compounds 3 and 7–12 had moderate antibacterial activities with MIC values ranging from 75 to 150 μg/mL against the bacteria. All samples were inactive against all tested human cancer cell lines, even at 100 μg/mL. This is the first investigation of the chemical constituents of A. manniana, as well as the first report of compounds 3, 7, and 10–12 from the genus Alsophila. The chemotaxonomic significance of these compounds is discussed.

FNDC5 inhibits malignant growth of human cervical cancer cells via restraining PI3K/AKT pathway.

Cervical cancer (CxCa) is the fourth most frequent cancer in women. This study aimed to determine the role and underlying mechanism of fibronectin type III domain-containing protein 5 (FNDC5) in inhibiting CxCa growth. Experiments were performed in human CxCa tissues, human CxCa cell lines (HeLa and SiHa), and xenograft mouse model established by subcutaneous injection of SiHa cells in nude mice. Bioinformatics analysis showed that CxCa patients with high FNDC5 levels have a longer overall survival period. FNDC5 expression was increased in human CxCa tissues, HeLa and SiHa cells. FNDC5 overexpression or FNDC5 protein not only inhibited proliferation, but also restrained invasion and migration of HeLa and SiHa cells. The effects of FNDC5 were prevented by inhibiting integrin with cilengitide, activating PI3K with recilisib or activating Akt with SC79. FNDC5 inhibited the phosphorylation of PI3K and Akt, which was attenuated by recilisib. PI3K inhibitor LY294002 showed similar effects to FNDC5 in HeLa and SiHa cells. Intravenous injection of FNDC5 (20 μg/day) for 14 days inhibited the tumor growth, and reduced the proliferation marker Ki67 expression and the Akt phosphorylation in the CxCa xenograft mouse model. These results indicate that FNDC5 inhibits the malignant phenotype of CxCa cells through restraining PI3K/Akt signaling. Upregulation of FNDC5 may play a beneficial role in retarding the tumor growth of CxCa.

The Anti-proliferative Effect of Caffeic Acid and Dactolisib on Human Cervical Carcinoma HeLa Cell Line

Cervical carcinoma is a common gynecological cancer with high mortality rate among women worldwide. Caffeic acid exerts an antiproliferative effect against cervical carcinoma. Dactolisib is a dual PI3K and mTOR inhibitor that has a therapeutic potential for cervical carcinoma. This study aimed to reveal the anti-proliferative effect of combination treatment of caffeic acid and Dactolisib on cervical carcinoma HeLa cell line. Cytotoxicity of caffeic acid and Dactolisib on HeLa cell line was assessed by MTS assay. Colony formation of HeLa cells treated with caffeic acid and Dactolisib was determined by staining colonies with crystal violet and visualizing under light microscope. Dactolisib decreased cell proliferation of HeLa cells in time and dose dependent manner. 5 μM caffeic acid did not show any significant change in cell viability of HeLa cells. Combination treatment of 5 μM caffeic acid and 0.5 μM Dactolisib showed decrease in cell viability of HeLa cells when compared to Dactolisib treated cells. Combination of caffeic acid and Dactolisib decreased colony diameter of HeLa cells significantly when compared to control group. Caffeic acid and Dactolisib shows anti-proliferative effect on human cervical carcinoma HeLa cell line, so further studies should be performed to reveal the mechanism of action.

Statement of Retraction: Synergistic, cytotoxic and apoptotic activities of olmesartan with NF-κB inhibitor against HeLa human cell line

Statement of Retraction: Synergistic, cytotoxic and apoptotic activities of olmesartan with NF-κB inhibitor against HeLa human cell line

Differential interactome mapping of aggregation prone/prion-like proteins under stress: novel links to stress granule biology

BackgroundAberrant stress granules (SGs) are emerging as prime suspects in the nucleation of toxic protein aggregates. Understanding the molecular networks linked with aggregation-prone proteins (prion protein, synuclein, and tau) under stressful environments is crucial to understand pathophysiological cascades associated with these proteins.MethodsWe characterized and validated oxidative stress-induced molecular network changes of endogenous aggregation-prone proteins (prion protein, synuclein, and tau) by employing immunoprecipitation coupled with mass spectrometry analysis under basal and oxidative stress conditions. We used two different cell models (SH-SY5Y: human neuroblastoma and HeLa cell line) to induce oxidative stress using a well-known inducer (sodium arsenite) of oxidative stress.ResultsOverall, we identified 597 proteins as potential interaction partners. Our comparative interactome mapping provides comprehensive network reorganizations of three aggregation-prone hallmark proteins, establish novel interacting partners and their dysregulation, and validates that prion protein and synuclein localize in cytoplasmic SGs. Localization of prion protein and synuclein in TIA1-positive SGs provides an important link between SG pathobiology and aggregation-prone proteins. In addition, dysregulation (downregulation) of prion protein and exportin-5 protein, and translocation of exportin-5 into the nucleus under oxidative stress shed light on nucleocytoplasmic transport defects during the stress response.ConclusionsThe current study contributes to our understanding of stress-mediated network rearrangements and posttranslational modifications of prion/prion-like proteins. Localization of prion protein and synuclein in the cytoplasmic SGs provides an important link between stress granule pathobiology and aggregation-prone proteins. In addition, our findings demonstrate nucleocytoplasmic transport defects after oxidative stress via dysregulation and nuclear accumulation of exportin-5.

Synthesis, Evaluation of anticancer and antimicrobial activities of some Schiff bases derivatives

In this research, compound [1,2-Bis-(4-amino-5-mercapto-4H-[1,2,4]triazol-3-yl)-ethane-1,2-diol] was used as starting material for synthesis different Schiff's Bases compounds. The fusion of tartaric acid with thiocarbohydrazide produce the compound (C1), the Schiff's bases (C2-C4) were created through the condensation of substances (C1) with different substituted benzaldehydes in presence of glacial acetic acid as catalyst. Thin layer chromatography (TLC) was used to confirm the compounds' purity, and spectroscopic methods were used to infer the compounds' structures (FTIR) and magnetic nuclear resonance spectroscopy (1H-NMR and 13C-NMR). The agar well diffusion method was used to test synthesized compounds for their antibacterial activity against K. pneumonia and S. aureus, and the findings were inconsistent. Target substances were tested for their ability to kill human breast cancer at concentrations of 50 and 100 g/mL. Human muscle tissue HC normal cell line, human cervical cancer Hela cell line, and HePG2 cell line. The results showed that the chemicals had potential cytotoxic activity against the Hela cell line, particularly compound (C4), which had the greatest inhibition at doses of 100 mg/mL among the examined substances

Natural Terpenes Inhibit the Cytopathogenicity of Naegleria fowleri Causing Primary Amoebic Meningoencephalitis in the Human Cell Line Model.

Naegleria fowleri is one of the free-living amoebae and is a causative agent of a lethal and rare central nervous system infection called primary amoebic meningoencephalitis. Despite the advancement in antimicrobial chemotherapy, the fatality rate in the reported cases is more than 95%. Most of the treatment drugs used against N. fowleri infection are repurposed drugs. Therefore, a large number of compounds have been tested against N. fowleri in vitro, but most of the compounds showed high toxicity. To overcome this, we evaluated the effectiveness of naturally occurring terpene compounds against N. fowleri. In this study, we evaluated the antiamoebic potential of natural compounds including Thymol, Borneol, Andrographolide, and Forskolin againstN. fowleri. Thymol showed the highest amoebicidal activity with IC50/24 h at 153.601 ± 19.6 μM. Two combinations of compounds Forskolin + Thymol and Forskolin + Borneol showed a higher effect on the viability of trophozoites as compared to compounds alone and hence showed a synergistic effect. The IC50 reported for Forskolin + Thymol was 81.30 ± 6.86 μM. Borneol showed maximum cysticidal activity with IC50/24 h at 192.605 ± 3.01 μM. Importantly, lactate dehydrogenase release testing revealed that all compounds displayed minimal cytotoxicity to human HaCaT, HeLa, and SH-SY5Y cell lines. The cytopathogenicity assay showed that Thymol and Borneol also significantly reduced the host cell cytotoxicity of pretreated amoeba toward the human HaCaT cell line. So, these terpene compounds hold potential as therapeutic agents against infections caused by N. fowleri and are potentially a step forward in drug development against this deadly pathogen as these compounds have also been reported to cross the blood-brain barrier. Therefore, an in vivo study using animal models is necessary to assess the efficacy of these compounds and the need for further research into the intranasal route of delivery for the treatment of these life-threatening infections.

Antibody-Free Fluorine-Assisted Metabolic Sequencing of RNA N4-Acetylcytidine.

N4-Acetylcytidine (ac4C) has been found to affect a variety of cellular and biological processes. For a mechanistic understanding of the roles of ac4C in biology and disease, we present an antibody-free, fluorine-assisted metabolic sequencing method to detect RNA ac4C, called "FAM-seq". We successfully applied FAM-seq to profile ac4C landscapes in human 293T, HeLa, and MDA cell lines in parallel with the reported acRIP-seq method. By comparison with the classic ac4C antibody sequencing method, we found that FAM-seq is a convenient and reliable method for transcriptome-wide mapping of ac4C. Because this method holds promise for detecting nascent RNA ac4C modifications, we further investigated the role of ac4C in regulating chemotherapy drug resistance in chronic myeloid leukemia. The results indicated that drug development or combination therapy could be enhanced by appreciating the key role of ac4C modification in cancer therapy.

Validation of mitotic harvesting method with human cervical carcinoma HeLa cells expressing fluorescent ubiquitination-based cell cycle indicators for radiation research.

The cell cycle is a series of events in the process of one cell giving rise to two daughter cells. The mitotic harvesting method, established by Terasima and Tolmach in the 1960s, causes minimal physiological stress on the cells and achieves a high degree of cell cycle synchrony by collecting only mitotic cells from a cultured cell system. The purpose of the present study is to validate the versatility of the mitotic harvesting method using human cervical cell line HeLa cells expressing Fluorescent Ubiquitination-based Cell Cycle Indicators (FUCCI) and to estimate the cell cycle-dependent changes in radiosensitivity in HeLa-FUCCI cells. The image analysis showed that cell cycle synchrony was maintained for at least 24 hours after mitotic cell collection. Also, the clonogenic assay demonstrated changes in radiosensitivity that were cell cycle dependent. These results indicate that the mitotic harvesting method using FUCCI-expressing cells has high versatility in the field of radiation cell biology.

Synthesis, spectral characterization, and biological activities of novel palladium(II) and platinum(II) complexes of active Schiff base ligands

ABSTRACT. A new series of palladium(II) and platinum(II) Schiff base complexes have been synthesized by the interaction of ligands N-(2-fluoro benzylidene)isonicotinohydrazone (L1H) and N-(2-fluorophenylethanone) isonicotinohydrazone (L2H) with PdCl2 and PtCl2. Elemental investigations, melting point determinations, molecular weight determinations, IR, 1H NMR, and UV-Visible spectral studies were used to describe the structure and bonding pattern of ligands and their metal complexes. These analyses revealed that the ligands coordinate with the metal ions in a monobasic bidentate manner and that the complexes have a square planar geometry. The antimicrobial activities of both the ligands and their palladium(II) and platinum(II) complexes have been tested against various bacterial and fungal strains and showed considerable antifungal and antibacterial characteristics. The in vitro cytotoxic activity of [Pt(L2H)]Cl2 complex was assessed by examining its potential to inhibit cell proliferation against the human HeLa cell line(cervical cancer cell line) using MTT assay and the antioxidant activity of [Pt(L1H)2]Cl2 compound was performed against DPPH. The results showed a dose-dependent cytotoxic and radical scavenging activity thus pointing towards the biological significance of Pt(II) complexes.
 KEY WORDS: Schiff base ligands, Antimicrobial activity, Scavenging activity, Cytotoxic
 Bull. Chem. Soc. Ethiop. 2023, 37(6), 1383-1396. DOI: https://dx.doi.org/10.4314/bcse.v37i6.7