HTC116 Cells Research Articles

Synthesis and biological evaluation of novel 3,6- amide and thioamide substituted- 2,3,4,9-tetrahydro-1H-carbazoles for anti-cancer activity

Herein, we report the synthesis of new compounds with demonstrated anticancer properties based on the 2,3,4,9-tetrahydro-1H-carbazole scaffold. The Fischer indolization method was used to close the heterocyclic motif. The synthesis method's scope and limitations were thoroughly assessed through a series of experiments. Biological assays revealed that two thioamide compounds exhibited significant anticancer activity against MCF-7, HTC116, and A596 cell lines. Comprehensive in vitro profiling included evaluation of cell cytotoxicity, morphological alterations, colony formation and cell adhesion in 3D cultures, cell cycle analysis, DNA damage induction, impact on mitochondria, and apoptosis. Ex ovo studies further demonstrated these compounds' potential to inhibit angiogenic processes. Our results indicate that the newly developed compounds activate processes leading to DNA damage and disruption of mitochondrial function.

Immunomodulatory, Antioxidant, and Potential Anticancer Activity of the Polysaccharides of the Fungus Fomitiporia chilensis.

Fomitiporia species have aroused the interest of numerous investigations that reveal their biological activity and medicinal potential. The present investigation shows the antioxidant, anticancer, and immunomodulatory activity of acidic polysaccharides obtained from the fungus Fomitiporia chilensis. The acidic polysaccharides were obtained for acidic precipitation with 2% O-N-cetylpyridinium bromide. Chemical analysis was performed using FT-IR and GC-MS methods. The antioxidant capacity of acidic polysaccharides from F. chilensis was evaluated by scavenging free radicals with an ABTS assay. Macrophage proliferation and cytokine production assays were used to determine the immunomodulatory capacity of the polysaccharides. Anti-tumor and cytotoxicity activity was evaluated with an MTT assay in the U-937, HTC-116, and HGF-1 cell lines. The effect of polysaccharides on the cell cycle of the HCT-116 cell line was determined for flow cytometry. Fourier Transform-infrared characterization revealed characteristic absorption peaks for polysaccharides, whereas the GC-MS analysis detected three peaks corresponding to D-galactose, galacturonic acid, and D-glucose. The secreted TNF-α concentration was increased when the cell was treated with 2 mg mL-1 polysaccharides, whereas the IL-6 concentration was increased with all of the evaluated polysaccharide concentrations. A cell cycle analysis of HTC-116 treated with polysaccharides evidenced that the acidic polysaccharides from F. chilensis induce an increase in the G0/G1 cell cycle phase, increasing the apoptotic cell percentage. Results from a proteomic analysis suggest that some of the molecular mechanisms involved in their antioxidant and cellular detoxifying effects and justify their traditional use in heart diseases. Proteomic data are available through ProteomeXchange under identifier PXD048361. The study on acidic polysaccharides from F. chilensis has unveiled their diverse biological activities, including antioxidant, anticancer, and immunomodulatory effects. These findings underscore the promising therapeutic applications of acidic polysaccharides from F. chilensis, warranting further pharmaceutical and medicinal research exploration.

Synthesis and Molecular Docking of some new Thiazolidinone and Thiadiazole Derivatives as Anticancer Agents.

New sets of functionalized thiazolidinone and thiadiazole derivatives were synthesized, and their cytotoxicity was evaluated on HepG2, MCF-7, HTC-116, and WI38 cells. The synthetic approach is based on the preparation of 4-(4-acetamidophenyl)thiosemicarbazide (4) and their thiosemicarbazones 5 a-e, which are converted to the corresponding thiazoldin-4-one compounds 6 a-e upon cyclization with ethyl bromoacetate. The thiadiazole compounds 9 and 12 were obtained by reacting 4-(4-acetamidophenyl)thiosemicarbazide with isothiocyanates and/or ethyl 2-cyano-3,3-bis(methylthio)acrylate, respectively. The thiazolidinone compounds 6 c and 6 e exhibited strong cytotoxicity against breast cancer cells, with an IC50 (6.70±0.5 μM) and IC50 (7.51±0.8 μM), respectively, very close to that of doxorubicin (IC50: 4.17±0.2 μM). In addition, the anti-cancer properties of the tested thiazolidinone and thiadiazole scaffolds were further explored by the molecular docking program (MOE)-(PDB Code-1DLS). Compounds 5 d, 5 e, 6 d, 6 e, and 7 have the best binding affinity, ranging from -8.5386 kcal.mol-1 to -8.2830 kcal.mol-1.

Establishment of XRD fourier fingerprint identification method of realgar decoction pieces and its anti-tumor activity in tumor-in-situ transplanted mice

Ethnopharmacological relevanceRealgar, a traditional mineral Chinese medicine, has been used in China for more than 2000 years. It has been recorded in many ancient and modern works that it has anti-cancer and anti-tumor effects. Of course, colon cancer is also within the scope of its treatment. Realgar needs to be processed into realgar decoction pieces by water grinding before being used for medicine. To ensure the consistency of efficacy and quality of realgar decoction pieces, modern methods need to be used for further quality control. Aim of the studyThe research of traditional mineral Chinese medicine is relatively difficult, and the related research is less. The purpose of this study is to control the quality of realgar decoction pieces by modern analytical technology and analyze its components. On this basis, its anti-colon cancer activity was discussed. Materials and methodsSeveral batches of realgar decoction pieces were analyzed by XRD, and the components of realgar decoction pieces were obtained. The quality control fingerprints of realgar decoction pieces were established by processing XRD spectra and similarity evaluation. Then, the effects of realgar decoction pieces on apoptosis of CT26 and HTC-116 cells were observed in vitro by Hoechst 33258 staining, flow cytometry, measurement of mitochondrial membrane potential and Western blot; In vivo, the mouse model of tumor-in-situ transplantation of colon cancer was established, and the related indexes were observed. ResultThe explorations showed that the XRD Fourier fingerprints of realgar decoction pieces samples that had the same phase revealed 10 common peaks, respectively. The similarity evaluation of the established XRD Fourier fingerprint was greater than 0.900. We also demonstrated that realgar decoction pieces can promote apoptosis and inhibit tumor growth in colon cancer cells, its activating effect on p53 protein, and its safety when used within reasonable limits. ConclusionThe quality control of realgar decoction pieces by XRD is scientific and has the inhibitory effect on colon cancer, which has the development potential.

"Turn-on" and pinhole-free ultrathin core-shell Au@SiO2 nanoparticle-based metal-enhanced fluorescent (MEF) chemodosimeter for Hg2.

This study reports a metal-enhanced fluorescence chemodosimeter for highly sensitive detection of Hg2+ ions. Silica-coated Au nanoparticles (Au@SiO2 NPs) with a pinhole-free 4-5 nm shell were synthesized and functionalized with a monolayer of turn-on fluorescent probes. Compared to other organic fluorescent probes suffering from poor biocompatibility and detection limits, this design of a monolayer of turn-on fluorescent probes immobilized on the Au@SiO2 NPs with a pinhole-free 4-5 nm shell avoids fluorescence quenching and allows the fluorescent probe within the field of the inner Au NPs to experience metal-enhanced fluorescence. With this design, the chemodosimeter permits fluorescence emission in the presence of Hg2+ ions, because they trigger the ring-opening reaction of the fluorescent probe immobilized on the Au@SiO2 NPs. Additionally, the fluorescent probe is distanced by the thin SiO2 shell from directly attaching to the metallic Au NPs, which not only avoids fluorescence quenching but allows the fluorescent probe within the long-ranged field of the inner Au NPs to experience metal-enhanced fluorescence. As a result, the detection limit for the chemodosimeter can reach up to 5.0 × 10-11 M, nearly two orders of magnitude higher than that achieved for the free fluorescent probe. We also demonstrate the acquisition of images of Hg2+ in HTC116 cells and zebrafish using a simple fluorescence confocal imaging technique. The fluorescence response results for HTC116 cells and zebrafish show that the probes can permeate into cells and organisms. Considering the availability of the many organic fluorescent probes that have been designed, the current designed metal-enhanced fluorescence chemodosimeter holds great potential for fluorescence detection of diverse species and fluorescence imaging.

Assessment of the safety of Levilactobacillus brevis CNCM I-5321, a probiotic candidate strain isolated from pulque with anti-proliferative activities.

Gut dysbiosis has been strongly correlated with colorectal cancer (CRC) development and the use of probiotics to modulate this imbalance represents a potential and promising therapy to prevent and treat CRC. For this reason, the identification of novel probiotic strains from diverse origins has widely increased in recent years, including traditional fermented foods. In this work we describe a new strain previously isolated from pulque (a traditional Mexican beverage), Levilactobacillus brevis CNCM I-5321, which may represent an interesting probiotic candidate to prevent and treat cancer. Indeed, our results show that CNCM I-5321 displays significant and specific antiproliferative capacities in human intestinal cancer cell lines (HT-29, HTC-116 and Caco-2 cells), but not in normal cells (FH cells). In addition, CNCM I-5321 is able to induce: (1) a pro-inflammatory immune response through stimulation of interleukin (IL)-2, IL-6, IL-12 and IL-17 cytokines and (2) apoptosis via activation of caspase 8. On the other hand, a minimum inhibitory concentration (MIC) assay revealed phenotypic resistance of this strain to ampicillin and chloramphenicol. However, no known transferable determinants were found in the genome of CNCM I-5321, thus this probiotic candidate presents no risk of horizontal transfer to the intestinal bacterial population. Finally, the safety status of CNCM I-5321 was evaluated using an innovative model of chicken embryo chorioallantoic membrane (CAM) to assess undesirable and/or toxic effects. Overall, our results support that CNCM I-5321 strain is non-pathogenic and safe for potential use as an anti-cancer candidate in human and animal medicine.

The Synthesis and Biological Activity of Organotin Complexes with Thio-Schiff Bases Bearing Phenol Fragments.

A number of novel di- and triorganotin(IV) complexes 1-5 (Ph2SnL1, Ph2SnL2, Et2SnL2, Ph3SnL3, Ph3SnL4) with mono- or dianionic forms of thio-Schiff bases containing antioxidant sterically hindered phenol or catechol fragments were synthesized. Compounds 1-5 were characterized by 1H, 13C NMR, IR spectroscopy, and elemental analysis. The molecular structures of complexes 1 and 2 in the crystal state were established by single-crystal X-ray analysis. The antioxidant activity of new complexes as radical scavengers was estimated in DPPH and ABTS assays. It was found that compounds 4 and 5 with free phenol or catechol fragments are more active in these tests than complexes 1-3 with tridentate O,N,S-coordinated ligands. The effect of compounds 1-5 on the promoted oxidative damage of the DNA by 2,2'-azobis(2-amidinopropane) dihydrochloride and in the process of rat liver (Wistar) homogenate lipid peroxidation in vitro was determined. Complexes 4 and 5 were characterized by more pronounced antioxidant activity in the reaction of lipid peroxidation in vitro than compounds 1-3. The antiproliferative activity of compounds 1-5 was investigated against MCF-7, HTC-116, and A-549 cell lines by an MTT test. The values of IC50 are significantly affected by the presence of free antioxidant fragments and the coordination site for binding.

Antioxidant, Immunomodulatory and Potential Anticancer Capacity of Polysaccharides (Glucans) from Euglena gracilis G.A. Klebs

The present study was carried out to determine the bioactivity of polysaccharides extracted from Euglena gracilis (EgPs). These were characterized by FT-IR and GC-MS. Cytotoxicity analyses (MTT) were performed on healthy human gingival fibroblast cell lines (HGF-1), obtaining an IC50 of 228.66 µg mL-1, and cell lines with anticancer activity for colon cancer (HCT-116), breast cancer (MCF-7), human leukemia (U-937, HL-60) and lung cancer (NCl-H460), showing that EgPs have anticancer activity, mainly in HTC-116 cells (IC50 = 26.1 µg mL-1). The immunological assay determined the immunomodulatory capacity of polysaccharides for the production of proinflammatory cytokines IL-6 and TNF-α in murine macrophages (RAW 264.7) and TNF-α in human monocytes (THP-1). It was observed that the EgPs had a stimulating capacity in the synthesis of these interleukins. The antioxidant capacity of polysaccharides and their biomass were analyzed using the ABTS method (18.30 ± 0.14% and (5.40 ± 0.56%, respectively, and the DPPH method for biomass (17.79 ± 0.57%). We quantitatively profiled HGF-1 proteins by liquid chromatography-tandem mass spectrometry analysis, coupled with 2-plex tandem mass tag labelling, in normal cells. In total, 1346 proteins were identified and quantified with high confidence, of which five were considered to be overexpressed. The data is available through ProteomeXchange, under identifier PXD029076.

Investigation of cytotoxic and genotoxic effects of olive leaf extract on colon cancer cells and normal cell lines

Colon cancer is a type of cancer that occurs when cells in the mucous layer membrane that surrounds the inner surface of the large intestine sections multiply unevenly. This study aimed to investigate olive leaf extract's cytotoxic and genotoxic effects on HTC-116 colon cancer cell lines and HDF healthy cell lines. In the study, olive leaf extract was prepared in methanol. The passaged HTC-116 and HDF cell lines were then incubated in Dulbecco's Modified Eagle's Medium (DMEM). Olive leaf extract extracted in methanol was applied to these cell lines at 3, 10, 20, 50, and 80 µg/ml and left for incubation for 24 hours. Then, the cytotoxic effect was determined by MTT analysis. The genotoxic effect of olive leaf extracts applied to HTC-116 and HDF cell lines after a 24-hour incubation period was determined by Hoechst stain. DNA damage was visualized with a DAPI filter on a camera-attached trinocular fluorescence microscope 30 minutes after staining with Hoechst. The MTT analysis revealed that the cytotoxic effects of olive leaf extract applied to the HTC-116 cell line were close to each group after the 24-hour incubation period. As a result of the examination of the genotoxic activity with Hoechst DNA staining in colon cancer cells (HCT-116), olive leaf extract at various concentrations treated to the cell line had a minor genotoxic effect at low doses (3, 10, and 20 µg/ml), while at high concentrations (50 and 80 µg). /ml), the genotoxic effects of the applications were determined. In examining the genotoxic impact of Hoechst DNA staining in the HDF cell line, no genotoxic effect was observed at low doses (3, 10, and 20 µg/ml) of olive leaf extract applied to the cell line at various doses. The little genotoxic effects of high doses (50 and 80 µg/ml) were also observed. Olive leaf contains phenolic substances and has antioxidant, antimicrobial, anti-inflammatory, antiatherogenic, anticarcinogenic and antiviral effects.Keywords: In vitro culture, plant regeneration, callus, hormones.

High‐polyphenol sorghum bran extracts decrease glutathione peroxidase expression and activity in colon cancer celle

Polyphenols are secondary plant metabolites found in many fruits, vegetables, and also grains. Sorghum bicoloris a cereal grain that contains varying amounts of polyphenols. Many polyphenols have been implicated in the regulation of colon cancer through modulating cellular antioxidant defense enzymes, which includes the glutathione peroxidases (GPX). These redox‐active enzymes protect cells from oxidative stress and are therefore involved in the regulation of tumorigenesis. Because cancer cells are thought to be undergoing oxidative stress, antioxidant defense enzymes, including but not limited to GPX, are often upregulated in those cells, contributing to their survival. The goal of our study is to investigate the impact of high‐polyphenol sorghum extracts on the expression and activity of these antioxidant enzymes. Our hypothesis is that glutathione peroxidase expression and catalytic activity will decrease in colon cancer cells treated with high‐polyphenol Sorghum extracts, thus potentially presenting a dietary chemoprevention strategy. The USDA ARS Kansas provided us with extracts from high‐polyphenol Sorghum bran, labeled ‘HP’ or ‘SC’. Human colon cancer cells (HCT116) were incubated with 1.25 mg extract per mL medium for 24hr hours. Total RNA was isolated with the Trizol method, and reverse transcribed to cDNA. mRNA expression was subsequently quantified using qPCR and normalized to the housekeeping gene GAPDH. Catalytic activity of GPX was determined with enzyme specific commercially‐available assays that measure the conversion of 1.0 µmol of NADPH to NADP+. Our preliminary results show that, compared to the solvent control, extract ‘HP’ slightly and extract ‘SC’ significantly (p<0.05) decreased mRNA expression of GPX 1 in HTC116 cells. However, GPX2 mRNA was modestly (p>0.05) increased in cells exposed to SC extract. Overall GPX activity, which measures catalytic activity of all present cellular GPXs, was significantly decreased by extracts ‘SC’ and ‘HP’. These results suggest that high polyphenol sorghum extracts may influence gene expression and catalytic activity of glutathione peroxidases involved in cellular antioxidant defense, and that GPX activity primarily reflects GPX1 as expected. Further investigation using other cell lines and antioxidant systems may help explain whether and how Sorghum extracts may modulate tumor prevention and promotion.

Activating transcription factor 3-activated long noncoding RNA forkhead box P4-antisense RNA 1 aggravates colorectal cancer progression by regulating microRNA-423-5p/nucleus accumbens associated 1 axis

ABSTRACT Long noncoding RNAs (lncRNAs) have vital roles in the progression of colorectal cancer (CRC). Forkhead box P4-antisense RNA 1 (FOXP4-AS1) showed a potential unfavorable prognostic factor for CRC, while its underlying mechanism remains elusive. Thus, the goal of this research is to determine mechanism of FOXP4-AS1 in CRC occurrence and development. Herein, a Dual-luciferase reporter assay was performed to assess the regulation of miR-423-5p to nucleus accumbens-associated protein 1 (NACC1) and activating transcription factor 3 (ATF3) to FOXP4-AS1 promoter. Hematoxylin-eosin (H&E) staining was performed to detect the pathological changes of tumor tissues. Flow cytometry, cell counting kit 8, Transwell, and wound healing assays were conducted to assess apoptosis, proliferation, migration, and invasion of CRC cells, respectively. The results showed that FOXP4-AS1 was highly expressed in CRC cell lines and tissues. CRC progression was promoted by the overexpression of FOXP4-AS1 in HTC116 cells and animal models. Furthermore, FOXP4-AS1 served as a molecular sponge for miR-423-5p, and NACC1 is a direct target of miR-423-5p. MiR-423-5p silencing or overexpression of NACC1 increased proliferation, migration, and invasion of HCT116 cells while suppressing apoptosis. We also found that the upregulation of FOXP4-AS1 was activated by ATF3 in CRC cells. Collectively, our results demonstrated that ATF3-activated FOXP4-AS1 aggravates CRC progression by regulating miR-423-5p/NACC1 axis, indicating a new target for CRC treatment.

Theonellamides J and K and 5-cis-Apoa-theopalauamide, Bicyclic Glycopeptides of the Red Sea Sponge Theonella swinhoei.

Theonella swinhoei is a fairly common inhabitant of reefs throughout the Indian and Pacific Oceans. Metabolomic analyses of samples of T. swinhoei collected in different depths in the Gulf of Aqaba revealed two chemotypes differing in the profiles of the theonellamides they produce, some of which seem to be unknown. Driven by this finding, we examined a sample of T. swinhoei collected more than 40 years ago in the southern part of the Gulf of Aqaba. Large-scale extract of this sample yielded four theonellamides, the known theopalauamide (4), as the major component, and three new metabolites, theonellamide J (1), 5-cis-Apoa-theopalauamide (2), and theonellamide K (3), as the minor components. The planar structure of these complex cyclic glycopeptides was elucidated by combination of 1D and 2D NMR techniques and HRESIMS. The absolute configuration of the amino acids was established by Marfey’s and advanced Marfey’s methods, and the absolute configuration of its galactose unit using “Tanaka’s method” for monosaccharides. The biological activity of the pure compounds was tested for antibacterial activity and for cytotoxicity to HTC-116 cell line. The compounds presented significant cytotoxicity against the HTC-116 cell line, illuminating the importance of the Apoa subunit for the activity.

Morus nigra-derived hydrophilic carbon dots for the highly selective and sensitive detection of ferric ion in aqueous media and human colon cancer cell imaging

Strongly fluorescent hydrophilic carbon dots (CDs) were synthesized through a one-step hydrothermal route using polysaccharide-rich Morus nigra fruit as the carbon source. These Morus nigra CDs (M-CDs) were extensively characterized using various analytical techniques to determine their structural and optical properties. The as-synthesized M-CDs were determined to be monodispersed with a mean diameter of 4.5 nm. Aqueous M-CD dispersions are brownish-yellow in color in daylight and emit bright cyan-blue light upon exposure to ultraviolet light. The M-CDs exhibit typical excitation-dependent emission behavior, with a high quantum yield of 24%. The analytical data show that the as-synthesized M-CDs exhibit strong fluorescence (FLR) and are very optically stable. Hence, the as-synthesized M-CDs are expected to use as fluorescent sensors for the highly selective and sensitive detection of Fe3+ ions by the fluorescence quenching mechanism. The quenching rate was linearly dependent on Fe3+ concentration, with a Fe3+ detection limit of 0.47 μM and a 5–30 µm detection range. Moreover, human colon cancer (HTC-116) cells were stained with the prepared M-CDs for 12 and 24 h for cell viability and microscopic analyses. The M-CDs-conjugated HTC-116 cells were brightly multicolor illuminated, emitting blue, green, and red light when excited through 405-, 488-, and 555-nm filters with distinct excitation ranges, respectively. This study provides a new route for the large-scale synthesis of highly fluorescent CDs for diverse applications using green sources and one-step hydrothermal carbonization procedures.

Abstract P025: NUC-3373 is a more potent inhibitor of thymidylate synthase than 5-FU and reduces generation of toxic metabolites

Abstract Background NUC-3373 is a novel anti-cancer agent designed to replace 5-FU, one of the most widely used therapies across a broad range of tumors, including colorectal cancer (CRC). 5-FU exerts its main anti-cancer activity via the active metabolite, fluorodeoxyuridine-monophosphate (FUDR-MP), which binds and inhibits thymidylate synthase (TS), preventing the conversion of dUMP into dTMP and disrupting DNA synthesis and repair. NUC-3373, a phosphoramidate transformation of FUDR-MP, is designed to bypass 5-FU resistance mechanisms associated with transport, activation and breakdown, and reduce generation of toxic metabolites including FUTP, which is incorporated into RNA causing myelosuppression and gastrointestinal toxicity, and FBAL which causes hand-foot syndrome. Thymidine supplementation rescues cells from NUC-3373 induced cytotoxicity, supporting a DNA targeted mode of action. The aim of this study was to further evaluate the differences between NUC-3373 and 5-FU. Methods CRC cell lines HCT116 and SW480 were exposed to sub-IC50 doses of NUC-3373 or 5-FU (0.1-25 μM) for 6h. At specific time-points, cells were harvested and analyzed as follows: TS inhibition by western blot, metabolite levels by mass spectrometry (LC-MS & LC-MS/MS) and cell cycle by flow cytometry. In rescue experiments, NUC-3373 and 5-FU were supplemented with thymidine (8 μg/mL) for 24h and cell survival assessed at 96h post-treatment. Results In both cell lines, NUC-3373 was a more potent inhibitor of TS than 5-FU with a higher proportion of TS protein bound to FUDR-MP at low concentrations. At 24h, 10 µM 5-FU was required to achieve the same level of TS binding as 0.1 µM NUC-3373 in HTC116 cells and as 0.5 µM NUC-3373 in SW480 cells. TS inhibition by NUC-3373 was almost maximal by 6 hours and was sustained for at least 48 hours. NUC-3373 generated significantly higher levels (50x) of free FUDR-MP compared to 5-FU, resulting in a more pronounced increase in dUMP levels (5x compared to 5-FU). At 48h, NUC-3373 treated cells remained arrested in S phase, while 5-FU treated cells had reverted to a normal cell cycle. FUTP was present in cells exposed to low doses of 5-FU (0.5 μM) but was not detectable in NUC-3373 treated cells. Finally, thymidine supplementation did not alter cell sensitivity to 5-FU but rescued cells treated with NUC-3373. Conclusion NUC-3373 generates higher intracellular levels of FUDR-MP and is a more potent inhibitor of TS than 5-FU, leading to more pronounced effects on cell cycle arrest and perturbation of the nucleotide pool that can result in misincorporation of uracil into DNA. Furthermore, NUC-3373 did not generate FUTP, consistent with the observation that patients treated with NUC-3373 in clinical studies have experienced much lower rates of FUTP-related toxicities. NUC-3373 is a potent TS inhibitor with a favorable safety profile. Citation Format: Jennifer Bré, Alison L. Dickson, Oliver J. Read, Ying Zhang, Peter Mullen, Clarissa M. Czekster, David J. Harrison. NUC-3373 is a more potent inhibitor of thymidylate synthase than 5-FU and reduces generation of toxic metabolites [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2021 Oct 7-10. Philadelphia (PA): AACR; Mol Cancer Ther 2021;20(12 Suppl):Abstract nr P025.

Evaluation of europium-based carbon nanocomposites as bioimaging probes: Preparation, NMR relaxivities, binding effects over plasma proteins and cytotoxic aspects

It is highly desirable to develop water-dispersible lanthanide-based luminescent probes with facile preparation, great bioavailability, and excellent photo properties for biomedical applications. Numerous carbon photoactive nanostructures (from diverse sources) have been reported for broad applications as surfactants, pollutants degradation, metal sensing and in vitro/in vivo bioimaging applications. Here, europium-based carbon nanocomposites (EuCQD) have been synthesized and well-characterized by their magneto-optical and biophysical properties. The obtained EuCQD is small in size (≅ 5 nm), highly water dispersible and composed essentially of carbon, europium and oxygen. Furthermore, the obtained nanocomposite presents Eu/CQD hybrid luminescent properties and high NMR relaxivities. The impact on biological media has been investigated based on plasma protein interactions and cytotoxicity assays. The results reveal that EuCQDs bind firmly (Ka ≈ 104–105 M−1) to studied plasma proteins (BSA and HTF) mainly by Van der Waals interaction and hydrogen bonds. Furthermore, protein CD spectra reveal that both proteins experience structural changes during EuCQD interaction, and the nanocomposite presents very low toxicity against HBMEC, A549, and HTC116 cells. All the presented results expose EuCQD as an excellent alternative to other lanthanide probes for bi-functional bioimaging applications and open the prospect of turning it accessible for industrial production and clinical translation.

Synthesis and Cytotoxic Activity of New Substituted Pyrazolo[3,4-b]pyridine Derivatives and Their Acyclic Nucleoside Analogs

As an important strategy, including incorporation of more than active core in one molecule, for finding potent candidates against cancer cells, a number of functionalized pyrazolopyridin derivatives linked to oxadiazole, dioxolane, acyclic sugar and fluorene ring systems, were synthesized through heterocyclization reactions. The derived sugar hydrazone and the corresponding acyclic C-nucleoside analog in addition to acyclic N-nucleoside were also prepared. The behavior of the afforded compounds as possible cytotoxic agents against human HTC116 and MCF7 cancer cells was investigated and the results showed that compounds 11-13 showed the highest activities against the two cancer cells. Other compounds revealed a type of selectivity toward one cancer cell while the activity was relatively lost against the other cancer cell line.

Diversity of the Chemical Profile and Biological Activity of Capsicum annuum L. Extracts in Relation to Their Lipophilicity.

Ethanol extracts of two types of pepper (sweet and hot) were separated into fractions with increasing lipophilicity. After drying the extracts and fractions, their chemical composition, anti-radical activity in the DPPH radical system, and cytotoxic activity against PC-3 and HTC-116 cells were determined. A detailed qualitative analysis of the fractions was performed with the LC-QTOF-MS method. It was found that the chemical composition of pepper fractions did not always reflect their biological activity. The highest antiradical activity was detected in the fraction eluted with 40% methanol from sweet pepper. The highest total content of phenolic compounds was found in an analogous fraction from hot pepper, and this fraction showed the strongest cytotoxic effect on the PC-3 tumour line. The LC-MS analysis identified 53 compounds, six of which were present only in sweet pepper and four only in hot pepper. The unique chemical composition of the extracts was found to modulate their biological activity, which can only be verified experimentally.

Moringa oleifera leaves crude aqueous extract down-regulates of BRCA1, mta-1 and oncogenes c-myc and p53 in AsPC-1, MCF-7 and HTC-116 cells

Moringa oleifera L. (Moringaceae) is a plant used for long time as a nutritional herb as well as for its various pharmacological activities including anticancer activity. Leaves, seed and bark contain active compounds such as phenolic acids, flavonoids, glucosinalates and isocyanates. Despite the extensive literature, the mechanism of action of active compounds still remains unknown. The plant leaves of wild and PMK-1 varieties of Moringa oleifera were extracted by hot water and crude extracts were assessed for their antiproliferative effect on AsPC-1, MCF-7 and HTC116 cells by MTT test. They were found to inhibit MCF-7, HTC116 and AsPC-1 cell proliferation at IC50 of 100, 125 and 240 μg/ml after 72 h of exposure, respectively. The extracts from PMK-1 variety did not show significant inhibition of cell proliferation. Wild type aqueous extract exerted its effect by down-regulation of p53 expression in all cell lines tested and by c-myc down-regulation in AsPC-1 cells. In addition, marker genes of cell lines such as breast cancer 1, early onset (BRCA-1) in MCF-7, metastasis-associated 1 (mta-1) in AsPC-1 and proliferation marker Ki-67 in HTC116 cells have also been down-regulated. The results suggest that polar compounds are involved in exerting these effects and further studies are needed to determine the precise mechanism of action of down-regulation of important genes for cell proliferation.

Tumour necrosis factor-α (TNF-α) enhances dietary carcinogen-induced DNA damage in colorectal cancer epithelial cells through activation of JNK signaling pathway

Colorectal cancer (CRC) is the third most common cancer worldwide and the second leading cause of cancer death. Benzo[a]pyrene (BaP) and 2-amino-1-methyl-6-phenylimidazol [4,5-b] pyridine (PhIP) present in cooked meat are pro-carcinogens and considered to be potential risk factors for CRC. Their carcinogenic and mutagenic effects require metabolic activation primarily by cytochrome P450 1 family enzymes (CYPs); the expression of these enzymes can be modulated by aryl hydrocarbon receptor (AhR) activation and the tumour microenvironment, involving mediators of inflammation. In this study, we hypothesized that tumour necrosis factor-α (TNF-α), a key mediator of inflammation, modulates BaP- and PhIP-induced DNA damage in colon cancer epithelial cells. Importantly, we observed that TNF-α alone (0.1–100 pg/ml) induced DNA damage (micronuclei formation) in HCT-116 cells and co-treatment of TNF-α with BaP or PhIP showed higher levels of DNA damage compared to the individual single treatments. TNF-α alone or in combination with BaP or PhIP did not affect the expression levels of CYP1A1 and CYP1B1 (target genes of AhR signaling pathways). The DNA damage induced by TNF-α was elevated in p53 null HTC-116 cells compared to wild type cells, suggesting that TNF-α-induced DNA damage is suppressed by functional p53. In contrast, p53 status failed to affect BaP and PhIP induced micronucleus frequency. Furthermore, JNK and NF-κB signaling pathway were activated by TNF-α treatment but only inhibition of JNK significantly reduced TNF-α-induced DNA damage. Collectively, these findings suggest that TNF-α induced DNA damage involves JNK signaling pathway rather than AhR and NF-κB pathways in colon cancer epithelial cells.

Design, synthesis and biological evaluation of combretastatin A-4 sulfamate derivatives as potential anti-cancer agents.

A series of combretastatin A-4 (CA-4) sulfamate derivatives were synthesized and their structure-activity relationship on tubulin, arylsulfatase and tumor cell antiproliferation inhibition was studied. Among them, compound 16a showed excellent potency as well as CA-4 under the same conditions against six tumor cells including HTC-116, HeLa, HepG2, MGC803, MKN45 and MCF-7 cells, respectively. Molecular docking revealed that several important hydrogen bond interactions were formed between the sulfamate group of 16a and the colchicine binding site of tubulin and steroid sulfatase respectively. Although compound 16a was less active than CA-4 in regard to its in vitro activity as an inhibitor of tubulin polymerization, it was effective as an inhibitor of arylsulfatase. This novel combretastatin A-4 sulfamate derivative has the potential to be developed as a dual inhibitor of tubulin polymerization and arylsulfatase for cancer therapy.