Selected Cancer Cell Research Articles

Development of tripodal imine metal chelates: Synthesis, physicochemical inspection, theoretical studies and biomedical evaluation

Direct condensation of 2-acetylferrocene with tris(2-aminoethyl)amine resulted in a novel tripodal imine ligand (L). Treatment of the metals’ chlorides (Fe3+, Cr3+, Co2+, Ni2+, Cu2+, Mn2+, Cd2+, and Zn2+) with equimolar ratio of the tripodal imine ligand led to cleaned production of the equivalent mononuclear complexes. They are well characterized by different physicochemical analyzing tools such as CHN, FT-IR as well as electronic spectroscopy, mass spectrometry and TGA analyses. Furthermore, scanning electron microscope (SEM) study for the tested ligand as well as Cd(II) chelate proved that it was nanosized. The stoichiometry of the prepared metal chelates in solution confirm M:L is 1:1 ratio. The DFT calculations demonstrated that all metal complexes possess octahedral geometry in accordance with the experimentally deduced geometry. The MEP surface indicated the reactive regions of the compounds for electrophilic and nucleophilic attack. HOMO-LUMO analysis implies charge transfer interaction during complex formation. Quantum chemical reactivity parameters showed that the complexes are stable and the decomposition process into constituent elements does not occur. Morover, anti-pathogenic and anticancer activities were studied against different bacterial, fungal strains and selected cancer cell lines. The metal chelates show potent anti-microbial and anti-cancer activity than its tripodal imine ligand. Furthermore, MOE-docking of the title ligand, Cu(II) as well as Cd(II) chelate was studied with crystal structure of the antimalarial drug Amediaquine (3AOU), colon cancer antigen10 (2HQ6), breast cancer (3HB5) and gastrointestinal cancer (4IJO).

Comparative Studies of Extracts Obtained from Brassica oleracea L. Plants at Different Stages of Growth by Isolation and Determination of Isothiocyanates: An Assessment of Chemopreventive Properties of Broccoli.

The main goal of this work was to develop analytical procedures for the isolation and determination of selected isothiocyanates. As an example, particularly sulforaphane from plants of the Brassicaceae Burnett or Cruciferae Juss family. The applied methodology was mainly based on classical extraction methods and high-performance liquid chromatography coupled with tandem mass spectrometry. Moreover, the effect of temperature on the release of isothiocyanates from plant cells was considered. The cytotoxic activity of the obtained plant extracts against a selected cancer cell line has also been included. The results allow evaluating the usefulness of obtained plant extracts and raw sprouts regarding their content of isothiocyanates-bioactive compounds with chemopreventive properties.

Combination of Indomethacin with Nanostructured Lipid Carriers for Effective Anticancer Therapy.

The anticancer potential of indomethacin and other nonsteroidal anti-inflammatory drugs (NSAIDs) in vitro, in vivo, and in clinical trials is well known and widely reported in the literature, along with their side effects, which are mainly observed in the gastrointestinal tract. Here, we present a strategy for the application of the old drug indomethacin as an anticancer agent by encapsulating it in nanostructured lipid carriers (NLC). We describe the production method of IND-NLC, their physicochemical parameters, and the results of their antiproliferative activity against selected cancer cell lines, which were found to be higher compared to the activity of free indomethacin. IND-NLC were fabricated using the hot high-pressure homogenization method. The nanocarriers were physicochemically characterized, and their biopharmaceutical behaviour and therapeutic efficacy were evaluated in vitro. Lipid nanoparticles IND-NLC exhibited a particle size of 168.1 nm, a negative surface charge (-30.1 mV), low polydispersity index (PDI of 0.139), and high encapsulation efficiency (over 99%). IND-NLC were stable for over 60 days and retained integrity during storage at 4 °C and 25 °C. The potential therapeutic benefits of IND-NLC were screened using in vitro cancer models, where nanocarriers with encapsulated drug effectively inhibited the growth of breast cancer cell line MDA-MB-468 at dosage 15.7 μM. We successfully developed IND-NLC for delivery of indomethacin to cancer cells and confirmed their antitumoral efficacy in in vitro studies. The results suggest that indomethacin encapsulated in lipid nanoparticles possesses high anticancer potential. Moreover, the presented strategy is highly promising and may offer a new alternative for future therapeutic drug innovations.

Abstract A033: Anti-proliferative effects of lentinan, a beta-glucan from shiitake mushroom (lentinula edodes)

Abstract Cancer is one of the most significant health challenges worldwide. Lentinan, a β-glucan from shiitake mushroom, Lentinula edodes, has been demonstrated to have an inhibitory effect on selected cancer cells, but results are inconclusive. The aim of the present study was to investigate the anti-proliferative effect of lentinan on breast adenocarcinoma cells (MCF-7), prostate carcinoma (DU-145), and ovarian carcinoma (SKOV3) using MTS (3-(4,5-dimethylthiazol-2-yl)-5—(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) assay and explore possible mechanisms of action of this compound. In the MCF-7 cells that were used as a positive control, lentinan without phenol red resulted in a significant inhibition of cell viability by 96% while in the presence of phenol red, the weak estrogen effect attributable to phenol red eliminated the significant inhibitory effect of lentinan. Treatment of DU-145 cells with different doses of lentinan resulted in up to a 42% inhibition in cell growth. In SKOV3 cells, lentinan induced a biphasic response where doses of 800 µg/ml or less increased cell viability by 76% – 148%; however, a dose of 1.6 mg/ml inhibited cell proliferation significantly by 87%. When SKOV3 cells were co-treated with lentinan (800 µg/ml or less) and laminarin (a Dectin-1 receptor antagonist), the proliferation-promoting effect of lentinan was dominant over the proliferation-inhibiting effect of laminarin. However, when lentinan was presented at significant higher levels (1600 µg/ml), the inhibitory effect of the two agents became additive in suppressing SKOV3 cell proliferation. Lentinan induced a biphasic response in human ovarian surface epithelial cells (HOSEpC) similar to SKOV3 cells, where the highest dose (1600 µg/ml) resulted in the inhibition of cell growth by 53%. Western blots after treatment of SKOV3 cells with 1600 µg/ml of lentinan demonstrated caspase-3 activation and a decreased anti-apoptotic protein Bcl-2 levels. Our findings reveal that lentinan can be considered as a potential anti-cancer drug for effective treatment of breast and prostate cancer. Citation Format: Titus Sombuor, Kenneth Shane Broughton, Michael Bergel. Anti-proliferative effects of lentinan, a beta-glucan from shiitake mushroom (lentinula edodes) [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2023 Oct 11-15; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2023;22(12 Suppl):Abstract nr A033.

Targeting ROS production through inhibition of NADPH oxidases.

NADPH oxidases (NOXs) are transmembrane enzymes that are devoted to the production of reactive oxygen species (ROS). In cancers, dysregulation of NOX enzymes affects ROS production, leading to redox unbalance and tumor progression. Consequently, NOXs are a drug target for cancer therapeutics, although current therapies have off-target effects: there is a need for isoenzyme-selective inhibitors. Here, we describe fully validated human NOX inhibitors, obtained from an in silico screen, targeting the active site of Cylindrospermum stagnale NOX5 (csNOX5). The hits are validated by in vitro and in cellulo enzymatic and binding assays, and their binding modes to the dehydrogenase domain of csNOX5 studied via high-resolution crystal structures. A high-throughput screen in a panel of cancer cells shows activity in selected cancer cell lines and synergistic effects with KRAS modulators. Our work lays the foundation for the development of inhibitor-based methods for controlling the tightly regulated and highly localized ROS sources.

Design, Synthesis, and Antitumor Efficacy of Substituted 2-Amino[1,2,4]triazolopyrimidines and Related Heterocycles as Dual Inhibitors for Microtubule Polymerization and Janus Kinase 2.

Preclinical and clinical studies have demonstrated the synergistic effect of microtubule-targeting agents in combination with Janus kinase 2 (JAK2) inhibitors, prompting the development of single agents with enhanced therapeutic efficacy by dually inhibiting tubulin polymerization and JAK2. Herein, we designed and synthesized a series of substituted 2-amino[1,2,4]triazolopyrimidines and related heterocycles as dual inhibitors for tubulin polymerization and JAK2. Most of these compounds exhibited potent antiproliferative activity against the selected cancer cells, with compound 7g being the most active. This compound effectively inhibits both tubulin assembly and JAK2 activity. Furthermore, phosphorylated compound 7g (i.e., compound 7g-P) could efficiently convert to compound 7g in vivo. Compound 7g, whether it was administered directly or in the form of a phosphorylated prodrug (i.e., compound 7g-P), significantly inhibited the growth of A549 xenografts in nude mice. The present findings strongly suggest that compound 7g represents a promising chemotherapeutic agent with high antitumor efficacy.

Synthesis of S-2-phenylchromane Derivatives and Evaluation of the Antiproliferative Properties as Apoptosis Inducers in Cancer Cell Lines.

Cancer remains one of the major health issues globally, where chemotherapy forms the main treatment mode for different types of cancers. Due to cancer cell ability to develop resistance, decreased clinical effectiveness of anticancer drugs can occur. Therefore, the need to synthesize novel antitumor drugs remains important. The aim of our work consisted of synthesizing S-2-phenylchromane derivatives containing the tertiary amide or 1,2,3-triazole fragments with promising anticancer activity. A series of S-2-phenylchromane derivatives were synthesized and evaluated for cytotoxic activity against three selected cancer cell lines (HGC-27 human gastric carcinoma cell line, Huh-7 epithelial-like tumorigenic cells, and A549 adenocarcinomic human alveolar basal epithelial cells) using the 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide (MTT) assay. Hoechst staining was used to detect the effects of S-2-phenylchromane derivatives on apoptosis. The apoptosis percentages were detected by annexin V-fluoresceine isothiocyanate/propidium iodide (Annexin V-FITC/PI) double staining assay with flow cytometry. Expression levels of apoptosis-related proteins were detected by western blot. Cell line A549, consisting of adenocarcinomic human alveolar basal epithelial cells, displayed the highest sensitivity to the S-2-phenylchromane derivatives. Among these compounds, E2 showed the most potent antiproliferative activity against A549 cells with an IC50 value of 5.60 μM. Hoechst staining and flow cytometry analysis revealed apoptosis in A549 cells by compound E2. In addition, activation of the expression levels of caspase-3, caspase-7, and their substrate poly (ADP-ribose) polymerase (PARP) by E2 was detected by western blot. In summary, results point towards compound E2, an S-2-phenylchromane derivative, as a potential lead molecule in anticancer agents for human adenocarcinomic alveolar basal cells based on the induction of apoptosis.

Cytotoxic Activities and Morphological Sudies of Thiophene, Thiazole and Pyridazine Derivatives Synthesized from Benzo[d]thiazole Derivatives

The benzo[d]thiazole derivatives 4a–c were synthesized and used for the synthesis of thiophene derivatives 6a–f. They form the arylhydrazone derivatives 8a–i which were capable to form pyridazine derivatives 9a–i and 10a–i. The latter compounds reacted with thioglycolic acid to produce the thiazole derivatives 12a–i and 13a–i, respectively. The thiazole derivatives 15a–c were also produced from 4a–c through their reactions with elemental sulfur and phenylisothiocyanate. Further heterocyclization reactions of 15a were carried out to produce thiophene derivatives. Evaluations of the synthesized products were carried out against some selected cancer cell lines and the most active compounds were further evaluated against the seventeen cancer cell lines classified according to the disease. Morphological changes of A549 cell line by the effect of compounds 13c and 13h were studied using microenvironment of the lung tissue where an excellent result was obtained.

Synthesis and Biological Evaluation of Novel 2-Amino-1,4-Naphthoquinone Amide-Oxime Derivatives as Potent IDO1/STAT3 Dual Inhibitors with Prospective Antitumor Effects.

Indoleamine-2,3-dioxygenase 1 (IDO1) and signal transducer and activator of transcription 3 (STAT3) have emerged as significant targets in the tumor microenvironment for cancer therapy. In this study, we synthesized three novel 2-amino-1,4-naphthoquinone amide-oxime derivatives and identified them as dual inhibitors of IDO1 and STAT3. The representative compound NK3 demonstrated effective binding to IDO1 and exhibited good inhibitory activity (hIDO1 IC50 = 0.06 μM), leading to its selection for further investigation. The direct interactions between compound NK3 and IDO1 and STAT3 proteins were confirmed through surface plasmon resonance analysis. A molecular docking study of compound NK3 revealed key interactions between NK3 and IDO1, with the naphthoquinone-oxime moiety coordinating with the heme iron. In the in vitro anticancer assay, compound NK3 displayed potent antitumor activity against selected cancer cell lines and effectively suppressed nuclear translocation of STAT3. Moreover, in vivo assays conducted on CT26 tumor-bearing Balb/c mice and an athymic HepG2 xenograft model revealed that compound NK3 exhibited potent antitumor activity with low toxicity relative to 1-methyl-L-tryptophan (1-MT) and doxorubicin (DOX). Overall, these findings provided evidence that the dual inhibitors of IDO1 and STAT3 may offer a promising avenue for the development of highly effective drug candidates for cancer therapy.

Spectroscopic and theoretical approach of DNA interaction and anticancer studies of bio-pharmaceutically active pyrimidine derived Cu(II) and Zn(II) complexes

New metal(II) complexes (CuL2 and ZnL2) with pyrimidine appended Schiff base ligand (HL) were synthesized and characterized by diverse spectroscopic methods, reveals the proposed structure of metal(II) complexes possess square planar geometry. DNA interaction ability of isolated compounds was studied by UV–Visible, fluorescence, viscometric and electrochemical methods and the results showed that isolated compounds intercalated with calf thymus DNA (CT-DNA). In addition, anticancer activities of HL, CuL2, and ZnL2 have been evaluated by MTT assay, signifying moderate cytotoxic activity on selected cancer cell lines and less toxicity on NHDF normal cell line due to the specific targeting of pyrimidine analogues. Moreover, antioxidant activities of isolated compounds towards diverse free radicals have been studied by spectrophotometric methods. These results showed that CuL2 has better antioxidant ability than HL and ZnL2. Finally, antimicrobial activities of isolated compounds against selected antimicrobial pathogens exposed that CuL2 has better antimicrobial activity on E. coli and C. albicans than other antimicrobial pathogens. The DFT calculations have been done to get the optimized geometry of the ligand and the metal complexes. In order to get a broad understanding of the interactions of these synthesized metal complexes, a detailed molecular docking analysis is taken up.

Disparities in Cisplatin-Induced Cytotoxicity-A Meta-Analysis of Selected Cancer Cell Lines.

Cisplatin is a classic anticancer drug widely used as a reference drug to test new metal complex drug candidates. We found an unexpected diversity in cisplatin-related cytotoxicity values, expressed as IC50 (the half-maximal inhibitory concentration) in tumour cell lines, such as MCF-7, HepG2 and HeLa. We reviewed the data published from 2018 to 2022. A total of 41 articles based on 56 in vitro experiments met our eligibility criteria. Using a meta-analysis based on a random effect model, we evaluated the cytotoxicity of cisplatin (IC50) after 48- or 72-h cell exposure. We found large differences between studies using a particular cell line. According to the random effect model, the 95% confidence intervals for IC50 were extremely wide. The heterogeneity of cisplatin IC50, as measured by the I2 index for all cancer cell lines, was over 99.7% at culture times of 48 or 72 h. Therefore, the variability between studies is due to experimental heterogeneity rather than chance. Despite the higher IC50 values after 48 h than after 72 h, the heterogeneity between the two culture periods did not differ significantly. This indicates that the duration of cultivation is not the main cause of heterogeneity. Therefore, the available data is diverse and not useful as a reference. We discuss possible reasons for the IC50 heterogeneity and advise researchers to conduct preliminary testing before starting experiments and not to solely rely on the published data. We hope that this systematic meta-analysis will provide valuable information for researchers searching for new cancer drugs using cisplatin as a reference drug.

Network-Based Molecular Features Selection to Predict the Drug Synergy in Cancer Cells

Identifying synergistic drug combinations in cancer treatment is challenging due to the complex molecular circuitry of cancer and the exponentially increasing number of drugs. Therefore, computational approaches for predicting drug synergy are crucial in guiding experimental efforts toward finding rational combination therapies. This research selects the molecular features of cancer cells with a diffusion network-based approach. Additionally, a model is developed using non-linear regression algorithms, namely Random Forest, Extremely Randomized Tree, and XGBoost, to predict the synergy score of drug combinations against the selected cancer cell features. The data used are drug combination screening data and cancer cell molecules provided by AstraZeneca-Sanger DREAM Challenge. The feature selection results demonstrate the relevance of cancer cell molecular features selected by the diffusion network. The prediction results indicate that the Random Forest algorithm shows a good correlation value of 0.570 in the model with a small dataset. In contrast, for the model with an instance or row size larger than the number of features or columns, the XGBoost algorithm achieves a good correlation value of 0.932.
 INDEX TERMS cancer, drug combination, drug synergy, network diffusion kernel, non-linear regression.

Zn(II) porphyrin-encapsulated MIL-101 for photodynamic therapy of breast cancer cells.

The photodynamic treatment is a non-aggressive and clinically accepted procedure for removing selected cancer cells with the activation of a photosensitizer agent at a specific light. In this study, the zinc porphyrin (Zn[TPP]) was prepared and encapsulated into the MIL-101 (Zn[TPP]@MIL-101). It was used in photodynamic therapy (PDT) against MCF-7 breast cancer cells under a red light-emitting diode. The structure, morphology, surface area, and compositional changes were investigated using conventional characterization methods including FTIR, FESEM, EDX, and BET analyses. The MTT assay was performed under light and dark conditions to explore the ability of Zn[TPP]@MIL-101 in PDT. The results have demonstrated the IC50 of 14.3 and 81.6mg/mL for light and dark groups, respectively. As the IC50 revealed, the Zn[TPP]@MIL-101 could efficiently eradicate cancer cells using PDT.

Biogenic Nanoparticles: Synthesis, Characterization, and Biological Potential of Gold Nanoparticles Synthesized using Lasiosiphon eriocephalus Decne Plant Extract.

Recent advancements in biomedicine have revolutionized nanomedicine as a therapeutic moderator in the management of both infectious and noninfectious diseases. In the current study we demonstrated biosynthesis of gold nanoparticles using aqueous leaf extract of Lasiosiphon eriocephalus as a capping and reducing agent and evaluation of their antioxidant, antibacterial, and anticancer properties. The biosynthesized LE-AuNPs were characterized by UV-Vis spectrophotometry, SEM, TEM, XRD, FTIR, DLS, and Zeta potential analysis. The antibacterial activity was checked by a minimum inhibitory concentration assay. The anticancer potential of biogenic LE-AuNPs was checked by cytotoxicity and genotoxicity assay against HeLa and HCT-15 cells. The characteristic surface plasmon resonance peak of the colloidal solution at 538 nm by UV-Vis spectrum confirmed the formation of LE-AuNPs in the solution. The SEM, TEM, and XRD revealed 20-60 sized hexagonal and crystalline LE-AuNPs. The LE-AuNPs displayed significant inhibition potential against DPPH and ABTS radicals in vitro. The LE-AuNPs demonstrated significant antibacterial potential. The results of cytotoxicity interpreted that biogenic gold nanoparticles exhibited strong dose and time-dependent cytotoxicity effect against selected cancer cell lines where IC50 of LE-AuNPs required to inhibit the growth of HeLa cells after 24 h and 48 h exposure were 5.65± 0.69 μg/mL and 4.37±0.23 μg/mL respectively and that of HCT- 15 cells was 6.46 ± 0.69 μg/mL and 5.27 ± 0.34 μg/mL, 24h and 48h post-exposure respectively. Findings from this study revealed that gold nanoparticles synthesized using L. eriocephalus, showed remarkable antioxidant, antimicrobial, and extensive cytotoxicity and genotoxicity activities.

5-Nitrofuryl-Containing Thiosemicarbazone Gold(I) Compounds: Synthesis, Stability Studies, and Anticancer Activity.

This work describes the synthesis of four gold(I) [AuClL] compounds containing chloro and biologically active protonated thiosemicarbazones based on 5-nitrofuryl (L=HSTC). The stability of the compounds in dichloromethane, DMSO, and DMSO/culture media solutions was investigated by spectroscopy, cyclic voltammetry, and conductimetry, indicating the formation overtime of cationic monometallic [Au(HTSC)(DMSO)]± or [Au(HTSC)2 ]± , and/or dimeric species. Neutral [{Au(TSC)}2 ] species were obtained from one of the compounds in dichlomethane/n-hexane solution and characterized by X-ray crystallography revealing a Au-Au bond, and deprotonated thiosemicarbazone (TSC). The cytotoxicity of the gold compounds and thiosemicarbazone ligands was evaluated against selected cancer cell lines and compared to that of Auranofin. Studies of the most stable, cytotoxic, and selective compound on a renal cancer cell line (Caki-1) demonstrated its relevant antimigratory and anti-angiogenic properties, and preferential accumulation in the cell nuclei. Its mode of action seems to involve interaction with DNA, and subsequent cell death via apoptosis.

In Vitro Anti-Inflammatory and Anticancer Evaluation of Mentha spicata L. and Matricaria chamomilla L. Essential Oils.

Spearmint, Mentha spicata L., and the German chamomile, Matricaria chamomilla L., preparations are used against inflammatory conditions traditionally and in modern medicinal applications. This present study aimed to evaluate pharma-grade essential oils for their in vitro anti-inflammatory and anticancer effects using COX-1, COX-2, and 5-LOX enzyme assays, as well as their apoptosis potential through the caspase pathway. In addition, the (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) (MTT) assay was applied to evaluate the in vitro cytotoxic effects using HEK293/A549, MCF7, and PC3 cell lines. Major components of M. spicata essential oil were confirmed both by gas chromatography (GC)-flame ionization detector (FID) and GC/mass spectrometry (MS) as 72.8% carvone, 12.6% limonene, 2.2% 1,8-cineole, 1.3% myrcene, and 1% trans-dihydrocarvone. The major components of M. chamomilla essential oil were also confirmed as 47.9% α-bisabolol oxide A, 16.8% α-bisabolol, 13.8%, (Z)-β-farnesene, 5.8% α-bisabolol oxide, and 4.7% α-bisabolene oxide A. The IC50 values for M. chamomilla essential oil on A549, MCF7, PC3, and HEK293 cells were calculated as 208.54 ± 1.39, 315.44 ± 1.17, 197.52 ± 0.98, and 638.79 ± 1.15 μg/mL, respectively, whereas the IC50 values for M. spicata essential oil on A549, MCF7, and PC3 cells were 672.13 ± 2.57, 708.27 ± 2.05, and 206.49 ± 1.48 μg/mL, respectively. For M. spicata essential oil, no cytotoxic effects on healthy HEK293 cells were observed at the tested concentrations. The essential oils increased the apoptotic activity, where all results were statistically significant. According to the anti-inflammatory evaluation, both M. chamomilla and M. spicata oils showed selective COX-2 inhibitions, where the SI values were calculated as 0.30 and 0.67, respectively. Overall, both M. spicata and M. chamomilla essential oils showed selective inhibition on the COX-2 enzyme and apoptosis against the selected cancer cell lines for the first time, to the best of our knowledge, with this specific dual mode of action. The initial results encourage further detailed in vivo experimental evaluations.

An aromatic plant bioactive compound corymbosin from Vitex negundo–mediated synthesis of zinc oxide nanoparticles, characterization, and their bioactivity against selected cancer cell lines and microbial pathogens

An aromatic plant bioactive compound corymbosin from Vitex negundo–mediated synthesis of zinc oxide nanoparticles, characterization, and their bioactivity against selected cancer cell lines and microbial pathogens

Abstract 549: Characterization of the selective inhibitory effect of KRas inhibitors in different cellular assay formats

Abstract The proto-oncogene KRas is a well-described small GTPase that functions as a molecular switch for major physiological signaling pathways involved in cell proliferation, differentiation and survival. It has been shown that activating mutations in KRas are among the most common oncogenic drivers of tumorigenesis. Missense mutations of KRas result in constitutive activation due to impaired hydrolysis of GTP which enhances tumor-promoting downstream signaling pathways. Most KRas mutations are located in exon 2 or 3 including the most frequently changed glycine 12 which is present in most pancreatic cancers as well as in colorectal cancers and lung adenocarcinomas. Although direct inhibition of KRas is challenging due to its small size, smooth surface and limited druggable pockets on its surface, first promising drug candidates for selected KRas mutants have been developed in recent years (e.g. Sotorasib, MRTX1133, BI-2852). It was the aim of this study to characterize the selective inhibitory effects of KRas inhibitors in a panel of cancer cell lines harboring different KRas mutations like G12C, G12V or G12D. So, we applied different cellular techniques including phosphorylation assays as well as 2D proliferation and 3D spheroid assays to screen KRas inhibitors for their effect on distinct KRas mutants. Firstly, inhibitors were tested in a cellular assay monitoring phosphorylation of the downstream target ERK at residues Thr202/Tyr204. Analysis applying the cellular pERK AlphaLisa assay showed a high selectivity of several inhibitors for specific KRas mutants, while RAF and MEK inhibitors showed no significant selectivity in the panel of cancer cell lines tested here. Next, KRas inhibitors were tested in a cellular 2D proliferation and a 3D spheroid assay to determine the inhibitory effect on cell growth in both settings. In line with published data, for some inhibitors we could observe a high selectivity for a specific KRas mutant which was even more pronounced in the 3D format as compared to the 2D setup. Most likely due to the fact that 3D growth assays mimic physiological conditions more closely than 2D settings. Interestingly, in the 2D and 3D assays we could not find such a clear inhibitory effect of the MEK and RAF inhibitors as compared to the cellular pERK assay. These results indicate that the described cellular pERK AlphaLisa assay established for selected cancer cell lines could be a useful tool to screen newly developed KRas inhibitors for their selective inhibition of specific KRas mutants. Additionally, the application of not only 2D proliferation but also 3D growth studies can further characterize the inhibitory potential of these KRas inhibitors. Citation Format: Franziska Fimm-Todt, Ezgi Dikici, Katharina Schaich, Oliver Siedentopf, Joachim Lauterwasser, Daniel Feger, Jan Erik Ehlert. Characterization of the selective inhibitory effect of KRas inhibitors in different cellular assay formats [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 549.

Abstract 953: Development of a predictive biomarker signature for the highly potent SIK3 inhibitor OMX-0407

Abstract Using the iOTarg genetic screening platform, salt-inducible kinase 3 (SIK3), a serine/threonine kinase of the AMP-activated protein kinase (AMPK) family was recently identified as a novel cell signaling modulator in cancer biology. OMX-0407, an orally available, single-digit nanomolar inhibitor of SIK3 was shown to inhibit tumor growth in a distinct panel of tumor models in vitro as well as in vivo by decreasing downstream pro-survival signaling of SIK3, enhancing caspase-mediated apoptosis and repolarizing the tumor microenvironment by decreasing regulatory T cells. In a comprehensive viability screening, more than 200 murine and human cancer cell lines and patient derived tumor models of different indications were used to identify a distinct subset of cancers highly sensitive towards OMX-0407. Representative for these tumors, OMX-0407 demonstrated dose-dependent anti-tumor efficacy in the renal cell carcinoma model RENCA, the squamous non-small cell lung cancer model (sqNSCLC) KLN205 and the murine colorectal tumor model MC38. With significantly prolonged overall survival of more than 60% tumor growth inhibition in all tumor models, OMX-0407 demonstrated equivalent or superior efficacy compared to anti-PD-1 monotherapy. In addition, OMX-0407 enhances the therapeutic potential of the standard of care chemotherapy in a broad range of human cancer cells and murine tumor models of sqNSCLC. Using comprehensive transcriptomics and proteomics analyses the selective activity profile of OMX-0407 on individual cancer cell lines and PDX models was used to identify and validate a predictive biomarker signature. With this gene signature, 84% of the selected cancer cells lines are correctly classified and would benefit from OMX-0407 therapy. The predictive biomarker will be evaluated in the clinical Phase I trial of OMX-0407 scheduled to start enrollment shortly. In summary, OMX-0407, a first-in-class oral SIK3 inhibitor, demonstrates potent monotherapy efficacy in tumor indications with high unmet medical need equal or superior to anti-PD-1 checkpoint blockade. By screening sensitive and non-sensitive tumor cell lines and PDX models, we identified a response-prediction biomarker signature. In upcoming clinical studies, this predictive biomarker signature will be evaluated for it’s potential to enrich for patients highly responsive to OMX-0407 therapy. Citation Format: Ilona-Petra Maser, Sonja Lacher, Vincent Piras, Barbara Kracher, Kai Zanziger, Murray Yule, Hannes Loferer, Stefan Bissinger. Development of a predictive biomarker signature for the highly potent SIK3 inhibitor OMX-0407 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 953.

Biogenic Synthesis of Silver Nanoparticles using Lasiosiphon eriocephalus (Decne): In vitro Assessment of their Antioxidant, Antimicrobial and Cytotoxic Activities.

The emergence of novel nanobiomedicine has transformed the management of various infectious as well as non-infectious diseases.Lasiosiphon eriocephalus, a medicinal plant, revealed the presence of active secondary metabolites and biological potentials. The present study was aimed to demonstrate the biosynthesis of silver nanoparticles using L. eriocephalus leaf extract (LE-AgNPs) and their biological properties, such as antioxidant, antibacterial and anticancer potential. The biosynthesized LE-AgNPs were characterized by UV-Visible spectroscopy, Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), X-ray diffraction, and Fourier transform infrared spectroscopy (FTIR) analysis. The antibacterial activity was checked by minimum inhibitory concentration (MIC) and zone of inhibition assays against Gram-positive and Gram-negative bacteria. The anticancer potential of biogenic LE-AgNPs was checked by cytotoxicity and genotoxicity assay against human cervical adenocarcinoma (HeLa) and human breast adenocarcinoma (MCF-7) cells. UV-visible spectroscopy confirmed the formation of silver nanoparticles by measuring the surface plasmon resonance peak of the colloidal solution at 410-440 nm. The results of SEM and TEM revealed the distribution and spherical shape of 20-50 nm sized AgNPs. XRD spectrum confirmed the characteristic peaks at the lattice planes 110, 111, 200, 220 and 311 of silver which confirmed the crystalline nature of biosynthesized LE-AgNPs. FTIR spectrum of plant extract and biogenic LE-AgNPs was recorded in between 1635-3320 cm-1 which confirmed stretching vibrations of possible functional groups C=C and O-H, responsible for the reduction of silver ions to silver nanoparticles. The in vitro antioxidant potential of LE-AgNPs was evaluated using DPPH (IC50 = 26.51 ± 1.15 μg/mL) and ABTS radical assays (IC50 =74.33 ± 2.47 μg/mL). The potential antibacterial effects of LE-AgNPs confirmed that 92.38 ± 2.70% growth inhibition occurred in E. coli in response to 0.1mg/mL concentration of LE-AgNPs followed by P. aeruginosa (75.51 ± 0.76), S. aureus (74.53 ± 1.26) and K. pneumoniae (67.4 ± 3.49). The cytotoxicity results interpreted that the biogenic silver nanoparticles exhibited strong dose and time dependent cytotoxicity effect against selected cancer cell lines where IC50 concentration of LE-AgNPs required to inhibit the growth of HeLa cells after 24 h exposure was 4.14 μg/mL and MCF7 cells 3.00 μg/mL, respectively. Significant DNA fragmentation was seen in the DNA extracted from HeLa and MCF-7 cells exposed to more than 2.5 to 10 μg/mL concentrations of LE-AgNPs. The overall findings from the present investigation indicated that the AgNPs synthesized using L. eriocephalus exerted strong biological potentials such as antioxidant, antimicrobial and extensive cytotoxicity and genotoxicity activities.