Clonogenic Assay Research Articles

A new insight on the effects of Schiff Base Iron (III) complexes in breast cancer cells for clinical radiotherapy

PurposeBreast cancer is a significant global health concern, and researchers strive to enhance radiotherapy outcomes while minimizing the side effects. Schiff Base Iron (III) Complexes are one of the prospective elements that can be used as radiosensitizer or radioprotective agents in cancer radiotherapy. This study investigates the potential effects of Schiff base (ligand 2; L2) with Fe(III) in MCF-7 breast cancer cells under clinical radiotherapy treatment. MethodsThe effects of the Schiff Base Iron (III) Complexes were measured using clonogenic assay with MCF-7 breast cancer cells. The cells were irradiated with megavoltage 6 MV photon, 6 MeV electron and high dose rate (HDR) brachytherapy with 192Ir source at different doses. Intercellular localization of Fe(III)-L2 complexes and antioxidant activities were also investigated. ResultsThe Fe(III)-L2 complexes were observed to be internalized by cellular nuclei without any effects on the cells. Interestingly, the Fe(III)-L2 complexes indicate radioprotective effects which provide intriguing insight towards application of metal ions complexes as radioprotector in cancer radiotherapy. The Fe(III)-L2 complexes also exhibit scavenging activities of free radical which further proved the antioxidative properties and radioprotective effects. ConclusionThe Fe(III)-L2 complexes show the radioprotective effects and antioxidant properties in MCF-7 cells, particularly for HDR brachytherapy. The findings suggest potential applications of the Fe(III)-L2 complexes as radioprotector agents in clinical radiotherapy.

8123 Identification Of Glutamine Metabolism As A Druggable Therapeutic Vulnerability For Adrenocortical Carcinoma

Abstract Disclosure: V. Chortis: None. C. Yao: None. C. Ribeiro: None. L. Kelley: None. L. Nagano: None. M. Berber: None. S. Raveenthiraraj: None. P. Vendramini: None. K. Kiseljak-Vassiliades: None. D.L. Carlone: None. M.C. Haigis: None. K.S. Borges: None. D.T. Breault: None. Dysregulation of cellular metabolism is a hallmark feature of cancer that can be targeted therapeutically but remains underexplored in adrenocortical carcinoma (ACC), despite the urgent need for improved treatments. We employed a recently developed transgenic mouse model of ACC (BPCre), driven by the two most common mutations in human ACC (β-catenin gain-of-function and p53 loss-of-function), aiming to characterize in vivo ACC metabolism at a tissue level and to identify metabolic vulnerabilities. We employed metabolomics (liquid chromatography-mass spectrometry) and transcriptomics (bulk RNA-seq) to compare tissue metabolism in spontaneous BPCre tumors with control adrenals. Polar metabolites were analyzed using a library that provides a representative cross-section of major carbon and nitrogen-handling pathways. We identified widespread dysregulation of tumor metabolism (64/175 metabolites significantly dysregulated, FDR<0.05), with the most significantly dysregulated pathways including purine and pyrimidine metabolism, proline and glutamate metabolism, glycolysis, and the pentose phosphate pathway (FDR<0.05). Orthogonal analysis by RNA-seq revealed congruent metabolic pathway alterations. Comparison of the most significantly dysregulated pathways between BPCre mouse tumors and human ACC using publicly accessible human transcriptomic datasets (TCGA and GTEx) revealed extensive overlap. Given the prominent dysregulation of several glutamine (Gln)-dependent metabolic pathways in mouse and human ACC, we hypothesized that Gln catabolism is likely to represent a targetable metabolic vulnerability in ACC. Pharmacological targeting of Gln metabolism using the Gln antagonist 6-Diazo-5-Oxo-L-Norleucine (L-DON) induced marked cytotoxicity in two cell lines derived from BPCre tumors and three human ACC cell lines (NCI-H295R, CU-ACC1-2), as assessed by cell viability and clonogenic assays. Remarkably, this effect was rescued only by nucleoside supplementation, suggesting that Gln’s contribution to de novo purine and pyrimidine biosynthesis is the critical metabolic dependency in ACC cells. Treatment with the L-DON pro-drug JHU-083, in vivo, led to marked growth inhibition of subcutaneous mouse ACC tumor implants in both immunocompetent and immunodeficient mice. As expected, tissue metabolomics of JHU-083-treated tumors confirmed extensive depletion of purine metabolites. Tumor immunophenotyping by flow cytometry revealed significantly increased infiltration with Natural Killer cells, likely potentiating the anti-tumor effect of glutamine antagonism in immunocompetent mice. JHU-083 was also effective against human NCI-H295R xenografts, in vivo. This work reveals important new insights into ACC metabolism and provides pre-clinical evidence supporting Gln antagonism as a new metabolic treatment approach for ACC. Presentation: 6/2/2024

LINC01116-dependent upregulation of RNA polymerase I transcription drives oncogenic phenotypes in lung adenocarcinoma

BackgroundHyperactive RNA Polymerase I (Pol I) transcription is canonical in cancer, associated with malignant proliferation, poor prognosis, epithelial-mesenchymal transition, and chemotherapy resistance. Despite its significance, the molecular mechanisms underlying Pol I hyperactivity remain unclear. This study aims to elucidate the role of long noncoding RNAs (lncRNAs) in regulating Pol I transcription in lung adenocarcinoma (LUAD).MethodsBioinformatics analyses were applied to identify lncRNAs interacting with Pol I transcriptional machinery. Fluorescence in situ hybridization was employed to examine the nucleolar localization of candidate lncRNA in LUAD cells. RNA immunoprecipitation assay validated the interaction between candidate lncRNA and Pol I components. Chromatin isolation by RNA purification and Chromatin Immunoprecipitation (ChIP) were utilized to confirm the interactions of candidate lncRNA with Pol I transcriptional machinery and the rDNA core promoter. Functional analyses, including lncRNA knock-in and knockdown, inhibition of Pol I transcription, quantitative PCR, cell proliferation, clonogenicity, apoptosis, cell cycle, wound-healing, and invasion assays, were performed to determine the effect of candidate lncRNA on Pol I transcription and associated malignant phenotypes in LUAD cells. ChIP assays and luminometry were used to investigate the transcriptional regulation of the candidate lncRNA.ResultsWe demonstrate that oncogenic LINC01116 scaffolds essential Pol I transcription factors TAF1A and TAF1D, to the ribosomal DNA promoter, and upregulate Pol I transcription. Crucially, LINC01116-driven Pol I transcription activation is essential for its oncogenic activities. Inhibition of Pol I transcription abrogated LINC01116-induced oncogenic phenotypes, including increased proliferation, cell cycle progression, clonogenicity, reduced apoptosis, increased migration and invasion, and drug sensitivity. Conversely, LINC01116 knockdown reversed these effects. Additionally, we show that LINC01116 upregulation in LUAD is driven by the oncogene c-Myc, a known Pol I transcription activator, indicating a functional regulatory feedback loop within the c-Myc-LINC01116-Pol I transcription axis.ConclusionCollectively, our findings reveal, for the first time, that LINC01116 enhances Pol I transcription by scaffolding essential transcription factors to the ribosomal DNA promoter, thereby driving oncogenic activities in LUAD. We propose the c-Myc-LINC01116-Pol I axis as a critical oncogenic pathway and a potential therapeutic target for modulating Pol I transcription in LUAD.Graphical

Relative biological effectiveness of clinically relevant photon energies for the survival of human colorectal, cervical, and prostate cancer cell lines

Objective.Relative biological effectiveness (RBE) differs between radiation qualities. However, an RBE of 1.0 has been established for photons regardless of the wide range of photon energies used clinically, the lack of reproducibility in radiobiological studies, and outdated reference energies used in the experimental literature. Moreover, due to intrinsic radiosensitivity, different cancer types have different responses to radiation. This study aimed to characterize the RBE of clinically relevant high and low photon energiesin vitrofor three human cancer cell lines: HCT116 (colon), HeLa (cervix), and PC3 (prostate).Approach.Experiments were conducted following dosimetry protocols provided by the American Association of Physicists in Medicine. Cells were irradiated with 6 MV x-rays, an192Ir brachytherapy source, 225 kVp and 50 kVp x-rays. Cell survival post-irradiation was assessed using the clonogenic assay. Survival fractions were fitted using the linear quadratic model, and survival curves were generated for RBE calculations.Main results.Cell killing was more efficient with decreasing photon energy. Using 225 kVp x-rays as the reference, the HCT116 RBESF0.1for 6 MV x-rays,192Ir, and 50 kVp x-rays were 0.89 ± 0.03, 0.95 ± 0.03, and 1.24 ± 0.04; the HeLa RBESF0.1were 0.95 ± 0.04, 0.97 ± 0.05, and 1.09 ± 0.03, and the PC3 RBESF0.1were 0.84 ± 0.01, 0.84 ± 0.01, and 1.13 ± 0.02, respectively. HeLa and PC3 cells had varying radiosensitivity when irradiated with 225 and 50 kVp x-rays.Significance.This difference supports the notion that RBE may not be 1.0 for all photons through experimental investigations that employed precise dosimetry. It highlights that different cancer types may not have identical responses to the same irradiation quality. Additionally, the RBE of clinically relevant photons was updated to the reference energy of 225 kVp x-rays.

Isoliquiritigenin: A natural compound with a promising role in inhibiting breast cancer lung metastasis

Background and aimIsoliquiritigenin (ISL) is a dietary bioactive compound that is derived from the roots of licorice and various other plants. Accumulating evidence suggests that ISL has noteworthy anticancer activity in a variety of cancer cells, but it is currently unknown how ISL affects the invasion and migration of breast cancer (BC) cells. Hence, the purpose of this study to determine the inhibitory effect of ISL on cell invasion, migration, and metastasis of BC cells in 4T1-treated lung metastatic animal models. Experimental ProcedureISL was found to inhibit BC lung metastasis, as confirmed by MTT assay, clonogenic assay, wound healing assay, transwell assay, histological analysis, western blot and bioluminescence assay in the xenograft model. Results and conclusionThe in vitro studies revealed that ISL treatment significantly prevented BC cell invasion and migration for 24 h. ISL decreased the protein expressions of PI3K, Akt, p-Akt, mTOR, p-mTOR, matrix metalloproteinase (MMP)-2, MMP-9, and N-cadherin , thereby inhibiting BC cell invasion. In addition, ISL decreased MMP-2/9 and N-cadherin expression in lung tissues and reduced mouse 4T1 BC cell lung metastasis. Based on these findings, it suggests that ISL inhibits cell migration and invasion in BC cells by inhibiting the PI3K/Akt signaling pathway and decreasing the activation of MMP-2 and MMP-9 expression. Therefore, ISL may be useful in managing BC invasion and metastasis.

Molecular Actions of Enicostemma hyssopifolium Whole Plant Extract on HPV18-Infected Human Cervical Cancer (HeLa) Cells.

Enicostemma hyssopifolium (E. hyssopifolium) contains several bioactive compounds with anti-cancer activities. This study was performed to investigate the molecular effects of E. hyssopifolium on HPV18-containing HeLa cells. The methanol extract of E. hyssopifolium whole plant was tested for cytotoxicity by MTT assay. A lower and higher dose (80 and 160 μg/mL) to IC50 were analyzed for colonization inhibition (Clonogenic assay), cell cycle arrest (FACS analysis), and induction of apoptosis (AO/EtBr staining fluorescent microscopy and FACS analysis) and DNA fragmentation (comet assay). The HPV 18 E6 gene expression in treated cells was analyzed using RT-PCR and qPCR. A significant dose-dependent anti-proliferative activity (IC50 - 108.25±2 μg/mL) and inhibition of colony formation cell line were observed using both treatments. Treatment with 80 μg/mL of extract was found to result in a higher percent of cell cycle arrest at G0/G1 and G2M phases with more early apoptosis, while 160 μg/mL resulted in more cell cycle arrest at SUBG0 and S phases with late apoptosis for control. The comet assay also demonstrated a highly significant increase in DNA fragmentation after treatment with 160 μg/mL of extract (tail moments-19.536 ± 17.8), while 80 μg/mL of extract treatment showed non-significant tail moment (8.152 ± 13.0) compared to control (8.038 ± 12.0). The RT-PCR and qPCR results showed a significant reduction in the expression of the HPV18 E6 gene in HeLa cells treated with 160 μg/mL of extract, while 80 μg/mL did not show a significant reduction. The 160 μg/mL methanol extract of E. hyssopifolium demonstrated highly significant anti-cancer molecular effects in HeLa cells.

Modified mesoporous silica nanocarriers containing superparamagnetic iron oxide nanoparticle, 5-fluorouracil or oxaliplatin, and metformin as a radiosensitizer, significantly impact colorectal cancer radiation therapy

This study investigates the anticancer effects of SPION-based silica nanocarriers carrying 5-fluorouracil (5-FU) or oxaliplatin (OX), and metformin (MET) on colorectal cancer cells. Nanocarriers were equipped with pH-responsive gold gatekeepers for controlled release, PEGylation for longer circulation, and folic acid (FA) for targeted delivery. The effects were evaluated by investigating cell viability, cellular uptake, flow cytometry, and clonogenic assay in vitro. The efficacy of the system was also tested in vivo on C57BL/6 mice bearing HT-29 tumors, and potential side effects were evaluatedNanocarriers were synthesized with hydrodynamic diameters of 79.8 nm for 5-FU and 85.2 nm for OX; zeta potentials of −21 and –22 mV, respectively, and remained stable after 72 h. Encapsulation efficiencies were 85 % for 5-FU, 80 % for OX, and 83 % for MET, with loading capacities of 44 %, 38 %, and 41 %, respectively. Drug release in acidic buffer was 38.7 % for 5-FU, 32.8 % for OX, and 43.5 % for MET. MTT assay showed increased toxicity due to FA conjugation, while PEGylation reduced the hemolysis activity. Targeted nanocarriers demonstrated superior cellular uptake and tumor localization compared to non-targeted variants. The combination of 5-FU-MET and OX-MET nanocarriers with radiation therapy (RT) demonstrated the greatest effect on their antitumor activity, accompanied by minimal side effects indicating effective tumor targeting in vivo. MRI and CT imaging further supported these findings. This study underscores the synergistic impact of MET alongside RT on the inhibition of cancer cells and tumor growth for both targeted 5-FU and OX nanocarriers reflecting the significant radiosensitizing properties of MET.

The Anticancer Properties, Cell-cycle Cytotoxicity and Apoptosis of Cissus rotundifolia, Trema orientalis, and Buddleja polystachya with Ocular Applications

BackgroundBuddleja polystachya, Trema orientalis, and Cissus rotundifolia were applied locally for various ocular purposes, while receiving few scientific evaluations. PurposeThis study aimed to screen the anticancer properties and determine the cell-cycle cytotoxicity and apoptotic activity of the most promising plant extract. MethodsIn this study, MTT assays with MCF7 (human breast adenocarcinoma), HT29 (human colorectal adenocarcinoma) and HepG2 (human liver adenocarcinoma) were used. In addition to MRC5 (normal human foetal lung fibroblast) was carried out for preliminary activity screening and selectivity. The most promising extract was subjected to GC-MS analysis to determine the phytochemical composition. Additionally, a clonogenic assay was performed to measure tumor cell survival and subsequent proliferative capacity after drug exposure was conducted for the most active extract(s) and finally western blotting was used to determine the expression change of the two selected proteins (survivin and CCND1) in order to determine the exact mechanistic features of the most promising plant extract. ResultsThe six extracts showed variable IC50 values ranging from 1.77- 40.97 μg/mL. The most active extracts were C. rotundifolia coded as (stem; BEP-03A and leaves; BEP-03B) on HepG2 cells and showed ∼ 4 and 8 fold selectivity compared to normal MRC5 cells. Both extracts showed a dose-dependent clonogenic effect on HepG2 cells, which was comparable to the effect of doxorubicin. The extract (BEP-03B) caused a significant decrease in the expression of survivin and CCND1 compared to the control GAPDH at its highest dose (12 µg/mL). The GC-MS chromatogram of the leaf of C. rotundifolia extract (BEP-03B) revealed the presence of 17 compounds, as the main phytoconstituents representing 57.5% of the total compounds present in BEP-03B. Three steroidal components (12, 14 and 15) were the main components, while compound stigmast-5-en-3-ol (compound 15) was the main component. ConclusionsLeaves of Cissus rotundifolia (Forssk.) Vahl, possess a significant cytotoxic effect and it may produce this effect, through apoptosis induction, perturbation, and disruption of the cell cycle. The detected phytoconstituents in the plant extract might be involved in the tested cytotoxic activity and its molecular apoptotic mechanism. Future studies are required to isolate the active ingredient(s) and confirm the therapeutic application(s).

Anticancer effects of emetine against cisplatin resistant pancreatic cancer cells via activation of Cyto-c/Caspase-9/Caspase-3/Bax/Bad axis

This investigation examines the potential pharmacotherapeutic efficacy of emetine, a natural alkaloid, against pancreatic ductal carcinoma, utilizing the PaCa3 cell line as a model. Employing a multifaceted approach, the study explores emetine's impact on cell viability, clonogenic potential, and apoptotic pathways, unravelling its molecular mechanisms. Additionally, an in-vivo assessment is conducted to evaluate emetine's antitumor efficacy against PaCa3 xenografts. Under standard conditions, PaCa3 cells were treated with varying emetine concentrations and subjected to MTT, clonogenic, DAPI, AO/EB, Annexin V-FITC/PI, and Western blot assays. In-vivo experiments involved the administration of emetine to female nude mice with PaCa3 xenografts, with subsequent measurement of tumor weight and volume. Statistical analyses included Tukey-test and ANOVA. Emetine demonstrated a significant and dose- and time-dependent cytotoxic effect on PaCa3 cells, reducing viability from 98% to 8% (***p<0.001). Clonogenic assay indicated a substantial inhibition of colony formation. DAPI staining revealed nuclear chromatin condensation, while AO/EB staining indicated heightened apoptosis. Annexin V-FITC/PI assay exhibited a dose-dependent decrease in normal cell viability and an increase in apoptotic events. Western blot analysis showcased concentration-dependent downregulation of anti-apoptotic Bcl-2 and upregulation of pro-apoptotic markers. In-vivo experiments illustrated a dose-dependent reduction in tumor weight (5 g to 1.6 g) and volume (2400 mm³ to 844 mm³) with emetine treatment. In conclusion, emetine emerges as a potent anticancer agent against pancreatic ductal carcinoma, exhibiting cytotoxicity, clonogenic inhibition, and apoptotic induction in PaCa3 cells. The in-vivo study further highlights its promising therapeutic potential, laying the groundwork for future clinical studies in pancreatic cancer treatment.

Mushroom against Cancer: Aqueous Extract of Fomitopsis betulina in Fight against Tumors

Background/Objectives: This study investigated the anticancer potential of an aqueous extract of the fungus Fomitopsis betulina. Methods: The study assessed the effect of the extract on nine cancer cell lines, including melanoma (LM-MEL-75), lung cancer (A549), and colorectal cancer (HT29, LoVo), and four normal cell lines. The cytotoxicity of the extract was evaluated using MTT, sulforhodamine-B (SRB), and clonogenic viability assays. Additionally, the study examined the effect of the extract on plant model organisms, garden cress (Lepidium sativum) and common onion (Allium cepa), to further investigate its biological activity. Results: The assays demonstrated selective cytotoxicity of the extract toward cancer cells, while sparing normal cells. The extract induced significant cytotoxic effects at lower concentrations in lung cancer, melanoma, and colon cancer cells, showing promise as a potential anticancer agent. The results also revealed that the extract inhibited seed germination and root growth, suggesting its potential to disrupt cell cycles and induce apoptosis. Conclusions: This study highlights the therapeutic potential of F. betulina and highlights the need for further research to identify the active ingredients and mechanisms underlying its anticancer effects.

Impact of Proton Irradiation Depending on Breast Cancer Subtype in Patient-Derived Cell Lines

Research on different types of ionizing radiation’s effects has been ongoing for years, revealing its efficacy in damaging cancer cells. Solid tumors comprise diverse cell types, each being able to respond differently to radiation. This study evaluated the radiobiological response of established (MDA-MB-231 (Triple negative breast cancer, TNBC), MCF-7 (Luminal A)) and patient-derived malignant cell lines, cancer-associated fibroblasts, and skin fibroblasts following proton IRR. All cell line types were irradiated with the proton dose of 2, 4, and 6 Gy. The radiobiological response was assessed using clonogenic assay, γH2AX, and p53 staining. It was noticeable that breast cancer lines of different molecular subtypes displayed no significant variations in their response to proton IRR. In terms of cancer-associated fibroblasts extracted from the tumor tissue, the line derived from a TNBC subtype tumor demonstrated higher resistance to ionizing radiation compared to lines isolated from luminal A tumors. Fibroblasts extracted from patients’ skin responded identically to all doses of proton radiation. This study emphasizes that tumor response is not exclusively determined by the elimination of breast cancer cells, but also takes into account tumor microenvironmental variables and skin reactions.

METTL3-mediated m6A modification of ZNF384 promotes hepatocellular carcinoma progression by transcriptionally activating ACSM1.

Hepatocellular carcinoma (HCC) is a lethal disease with a high mortality rate, and its development is influenced by various molecular mechanisms. Zinc finger protein 384 (ZNF384) has been reported to be involved in the progression of several cancers; however, its role in HCC remains elusive. mRNA expression levels were analyzed by quantitative real-time polymerase chain reaction, while western blotting and immunohistochemistry were performed to validate protein expression. Cell proliferation, apoptosis, and metabolic activities were examined using clonogenicity, flow cytometry, and specific assay kits. A xenograft mouse model was employed to assess the impact of acyl-CoA synthetase medium-chain family member 1 (ACSM1) depletion on HCC cell malignancy in vivo. Chromatin immunoprecipitation assay and dual-luciferase reporter assay were conducted to explore the association between ZNF384 and ACSM1. We found that ACSM1 and ZNF384 were significantly upregulated in HCC tissues and cells when compared with normal liver tissues and human liver immortalized cells. Knockdown of ACSM1 inhibited HCC cell proliferation and glucose metabolism and induced cell apoptosis. Furthermore, ACSM1 depletion suppressed the malignant progression of HCC cells in vivo. Our data indicated that ZNF384 transcriptionally activated ACSM1 in HCC cells. Overexpression of ACSM1 reversed the inhibitory effect of ZNF384 depletion on HCC cell malignancy. Further, methyltransferase-like 3 (METTL3) stabilized ZNF384 mRNA through m6A methylation. METTL3-mediated m6A modification of ZNF384 contributed to the progression of HCC by transcriptionally activating ACSM1. This finding suggests potential therapeutic targets for this devastating disease.

Ang-1 promotes tumorigenesis and mediates the anti-cancer effects of Artesunate on Choroidal melanoma via the regulation of Akt/mTOR signaling pathway

The impact of Ang-1 on tumors remains a subject of contention, with its mechanism of action exhibiting complexity in the progression of diverse tumor types. Ang-1 has been shown to promote the progression of glioma, glioma, esophageal and human cervical cancer, whereas it exerts inhibitory effects on the growth of breast and colon cancer. However, the specific function of Ang-1 in CM has not been clarified. This research aims to explore the function of Ang-1 on CM and the underlying mechanism. WB and qPCR were utilized to measure the expression levels of different factors in CM cells. Clonogenic, CCK-8 and Transwell migration assay were used to probe CM cells’ proliferation and migration ability. Xenograft tumor model was used to testify the effect of Ang-1 and Artesunate (ART) on the growth of CM in vivo. We found Ang-1 promoted CM proliferation and migration, while it was inhibited by ART in vitro. Moreover, both ART treatment and Ang-1 knockdown had the effect of suppressing tumor growth in CM xenograft model. Mechanically, Ang-1 activated Akt/mTOR pathway and induced epithelial-mesenchymal transition (EMT) in CM cells. Furthermore, ART regulated Akt/mTOR pathway by decreasing the expression of Ang-1 in CM cells. Ang-1 promotes tumorigenesis of CM by regulating Akt/mTOR pathway, which can be inhibited by ART.

Abstract C029: Surface localization and targeting of enolase-1 (ENO1) as a novel theranostic approach for docetaxel-resistant neuroendocrine prostate cancer

Abstract Prostate cancer (PCa) is American men's second most common cancer. This cancer exhibits the most significant racial disparities among all cancer types, with elevated incidence and mortality in men of African ancestry. Although taxane-based chemotherapy with docetaxel (DTX) and cabazitaxel is the last line of defense for metastatic Castration Resistant Prostate Cancer (mCRPC), it invariably fails due to the development of chemoresistance. The protein-specific membrane antigen (PSMA) is currently an effective target for the imaging and therapy of mCRPC. However, although PSMA radioligand therapy (PSMA-RLT) is a theranostic option for men with advanced PCa, about 30% have a limited response to this treatment, particularly those that lack PSMA. In addition, some reports indicate that PSMA is suppressed in neuroendocrine PCa (NEPC), making it an unreliable theranostic target for this aggressive subtype. The glycolytic enzyme Enolase (ENO) is a promising theranostic alternative due to its cell surface localization in many human tumors. We hypothesized that ENO1 is abundant on the surface of NEPC-like cell lines and can be targeted with small molecule inhibitors (SMIs) that could potentially be used as theranostic agents. Western blotting (WB) analysis revealed that DTX-sensitive PCa cell lines expressing NEPC markers express both ENO1 and ENO2. By contrast, DTX-resistant NEPC-like cells only express ENO1 and therefore have a metabolic vulnerability due to the loss of ENO2. Additionally, we observed by WB and confocal microscopy changes in the expression and localization of ENO1 in NEPC-like cell lines under different glucose concentrations. Our results showed that under high glucose conditions, found on metabolically active metastatic tumors, ENO1 is highly abundant on the cell surface, making it a promising candidate target for theranostics. However, standard glucose conditions resulted in ENO1 downregulation, most likely due to inhibition of the activity of the c-MYC oncogene and upregulation of MBP1, the small splice variant of ENO1 that blocks the transcriptional activity of c-MYC. We also evaluated the cytotoxicity of SMIs designed to target ENO1 in chemoresistant NEPC-like cell lines using MTT viability assays, clonogenic assays, and Hoffman Modulation microscopy imaging. We observed that these inhibitors can significantly impair, with IC50 values at low micromolar concentrations, the proliferation and clonogenicity of NEPC cell lines. These results support our long-term goal to identify an alternative theranostic option for patients with NEPC by establishing ENO1 as a novel theranostic target. Citation Format: Krystal R. Santiago Torres, Kristen Whitley, Alfonso Duran, Bhaskar Das, Carlos Casiano, Frankis Almaguel. Surface localization and targeting of enolase-1 (ENO1) as a novel theranostic approach for docetaxel-resistant neuroendocrine prostate cancer [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr C029.

Jellein-I-conjugated gold nanoparticles: Insights into the antibacterial, antibiofilm activities against MRSA, and anticancer properties

Antimicrobial peptides (AMPs) and their conjugation with nanoparticles hold promise for targeting Methicillin-resistant Staphylococcus aureus (MRSA). In this study, Jellein-I peptide, with a cysteine at the C-terminus, was conjugated to gold nanoparticles (GNPs) to enhance its antibacterial, antibiofilm, and anticancer activities. The GNPs were synthesized and then conjugated to Jellein-I, forming Jellein-I-Cys-GNPs. The nanoparticles were characterized using UV–visible spectroscopy, transmission electron microscopy (TEM), dynamic light scattering (DLS), and Fourier transform infrared (FTIR) spectroscopy. UV–visible spectroscopy, DLS, and TEM confirmed the formation of GNPs with an average size of 5.5 nm. The UV–visible spectroscopy and FTIR results indicated the presence of peptide functional groups on the surface of the GNPs. To assess antibacterial activity, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) assays were performed against MRSA strains. The conjugated Jellein-I exhibited lower MIC and MBC values (94 μM) compared to the free peptide (512 μM) against both clinical and standard MRSA strains. Additionally, GNP-conjugated Jellein-I demonstrated antibiofilm activity, inhibiting and removing biofilms while reducing metabolic activity by more than 82 %, 44 %, and 72 %, respectively. Cell viability studies on rat dermal fibroblast (RDF) cells showed over 80 % viability across all treatment concentrations. Furthermore, a clonogenic assay on the metastatic melanoma cell line (A375) demonstrated that GNP-conjugated Jellein-I had significantly better anticancer effects than the free peptide, even at a concentration as low as 9 μM. Our findings suggest that the conjugation of Jellein-I-Cys to GNPs could be a promising formulation for enhancing the antibacterial, antibiofilm, and anticancer activities of peptides. Further in vivo studies may establish this new nanoformulation as a potential therapeutic candidate for MRSA infections and cancer treatment.

MiR-2110 Affects the Biological Behaviors of Lung Adenocarcinoma by Regulating CDT1

To investigate the effect of miR-2110 on the biological behaviors, such as cell proliferation, apoptosis, and metastasis, of lung adenocarcinoma (LUAD) cells by means of cell and animal experiments. Bioinformatics websites, including ENCORI, TargetScan, miRTarBase, and Tarbase, were used to analyze the changes in the expression of miR-2110 in LUAD samples and to predict miR-2110 target. LUAD tissue samples and cells were collected and the changes in the expression of miR-2110 were verified through PCR technology. CCK-8 assay, clonogenic assay, Transwell assay, and flow cytometry were conducted to analyze alterations in the functions of LUAD cells. In addition, 10 BALB/c female nude mice aged 6 to 8 weeks were randomly divided into 2 groups, and the effect of miR-2110 on LUAD was investigated by in vivo experiments. miR-2110 was significantly decreased in LUAD tissues and cells compared with the normal lung tissues. miR-2110 overexpression inhibited the proliferation and metastasis of LUAD cells and promoted the apoptosis of tumor cells (P<0.05). Bioinformatics prediction and dual luciferase reporter gene assay results confirmed that miR-2110 could target and bind to CDT1. In addition, overexpression of CDT1 gene reversed the proliferation, metastasis, and apoptosis of miR-2110 compared with the miR-2110 overexpression group (P<0.05). Nude mice in vivo experiments showed that miR-2110 overexpression significantly decreased the expression of Ki67, a tumor proliferation index, and vimentin and MMP9, two metastasis indices, compared with the control group. miR-2110 can inhibit proliferation and metastasis of LUAD by targeting CDT1, providing a new rationale for the treatment of LUAD.

Oxazolidinone antibiotics impair ex vivo megakaryocyte differentiation from hematopoietic progenitor cells and their maturation into platelets.

Oxazolidinones (linezolid and tedizolid) adverse reactions include thrombocytopenia, the mechanism of which is still largely unknown. In cultured cells, oxazolidinones impair mitochondrial protein synthesis and oxidative metabolism. As mitochondrial activity is essential for megakaryocyte differentiation and maturation into platelets, we examined whether oxazolidinones impair these processes ex vivo and alter, in parallel, the activity of mitochondrial cytochrome c-oxidase (CYTOX; enzyme partly encoded by the mitochondrial genome) and cell morphology. Human CD34+ cells were isolated, incubated with cytokines (up to 14 days) and clinically relevant oxazolidinone concentrations or in control conditions, and used for (i) clonogenic assays [counting of megakaryocyte (CFU-Mk), granulocyte-monocyte (CFU-GM), burst-forming unit-erythroid (BFU-E) colonies]; (ii) the measure of the expression of megakaryocyte surface antigens (CD34 to CD41 and CD42); (iii) counting of proplatelets; (iv) the measurement of CYTOX activity; and (v) cell morphology (optic and electron microscopy). Oxazolidinones caused a significant decrease in BFU-E but not CFU-Mk or CFU-GM colonies. Yet, the megakaryocytic lineage was markedly affected, with a decreased differentiation of CD34+ into CD41+/CD42+ cells, an abolition of proplatelet formation and striking decrease in the numbers of large polylobulated nucleus megakaryocytes, with a complete loss of intracellular demarcation membrane system, disappearance of mitochondria, and suppression of CYTOX activity. These alterations were more marked in cells incubated with tedizolid than linezolid. These data suggest that oxazolidinones may induce thrombocytopenia by impairing megakaryocytic differentiation through mitochondrial dysfunction. Pharmacological interventions to prevent this toxicity might therefore be difficult as mitochondrial toxicity is most probably inherently linked to their antibacterial activity.

TOPAS-Tissue: A Framework for the Simulation of the Biological Response to Ionizing Radiation at the Multi-Cellular Level.

This work aims to develop and validate a framework for the multiscale simulation of the biological response to ionizing radiation in a population of cells forming a tissue. We present TOPAS-Tissue, a framework to allow coupling two Monte Carlo (MC) codes: TOPAS with the TOPAS-nBio extension, capable of handling the track-structure simulation and subsequent chemistry, and CompuCell3D, an agent-based model simulator for biological and environmental behavior of a population of cells. We verified the implementation by simulating the experimental conditions for a clonogenic survival assay of a 2-D PC-3 cell culture model (10 cells in 10,000 µm2) irradiated by MV X-rays at several absorbed dose values from 0-8 Gy. The simulation considered cell growth and division, irradiation, DSB induction, DNA repair, and cellular response. The survival was obtained by counting the number of colonies, defined as a surviving primary (or seeded) cell with progeny, at 2.7 simulated days after irradiation. DNA repair was simulated with an MC implementation of the two-lesion kinetic model and the cell response with a p53 protein-pulse model. The simulated survival curve followed the theoretical linear-quadratic response with dose. The fitted coefficients α = 0.280 ± 0.025/Gy and β = 0.042 ± 0.006/Gy2 agreed with published experimental data within two standard deviations. TOPAS-Tissue extends previous works by simulating in an end-to-end way the effects of radiation in a cell population, from irradiation and DNA damage leading to the cell fate. In conclusion, TOPAS-Tissue offers an extensible all-in-one simulation framework that successfully couples Compucell3D and TOPAS for multiscale simulation of the biological response to radiation.

Anti-neoplastic effect of heterophyllin B on ovarian cancer via the regulation of NRF2/HO-1 in vitro and in vivo

BackgroundHeterophyllin B (HB) is a cyclic peptide with anti-neoplastic effect on many cancers. However, its effect and mechanism of action in ovarian cancer cells are still unknown. PurposeThe primary objective of this study was to assess the impact of HB on the proliferation of ovarian cancer (OC) cells and delve into the underlying mechanisms involved. MethodsWe performed CCK-8 assays, HE staining, KI67 staining, clonogenic formation assays, Annexin V-FITC/PI staining, tumor invasion assays, and migration assays to detect the effects of HB on cell viability, proliferation, apoptosis, migration, and invasion in ovarian cancer cells. Additionally, real-time fluorescent quantitative PCR (qPCR) and Western blotting were utilized for verification. The expression of NF-E2-related factor 2 (NRF2) and heme oxygenase 1 (HMOX1/HO-1) signaling molecules was detected using qPCR and Western blotting. A specific inducer, Hemin, was used to activate HO-1 and Nrf2 overexpression, in order to verify the pharmacological mechanism of HB on ovarian cancer cells. The binding relationship between HB and NRF2 was investigated through molecular docking. ResultsHB treatment inhibited the viability of OC cells, meanwhile it showed suppressive effect on the proliferation, migration, and invasion of OC cells, Meanwhile, HB could promote the apoptosis of tumor cells. For the mechanisms, we found that HB treatment could significantly down-regulate the levels of NRF2/HO-1. Consistent with the results of in vitro experiments, administration of HB significantly delayed tumor growth in OVCAR8 xenografted nude mice, and inhibited the expression of Ki67, Nrf2 and HO-1. ConclusionThis study demonstrated that HB had anti-neoplastic effect on OC by inhibiting Nrf2/HO-1 signaling pathway and may be a potential drug for the treatment of OC.

Increasing prostate cancer radiosensitivity by miR-7-5p knockdown of anti-apoptotic genes

Despite the success of radiotherapy for prostate cancer treatment, the recent discovery of radiation resistance prevents it from reaching its full potential. This study aims to use hsa-miR-7-5p for the expression of anti-apoptotic genes. The search for anti-apoptotic genes was carried out through databases. The selected genes included XIAP, MCL1, REL, and BIRC3. Our selection was based on the best miRNA because it has a greater impact on genes. The second step involved transfecting the miRNA into a prostate cancer cell line. Subsequently, radiosensitivity was tested using real-time PCR, clonogenic assay, and annexin V flow cytometry. The highest apoptosis rate in the transfected cells was at 0 Gy in hsa-miR-7-5p (28.88 ± 0.80), plenti III (18.81 ± 0.59), and the control group (4.10 ± 1.52) (P<0.001). Also, its rate was at 4 Gy in hsa-miR-7-5p (36.11 ± 1.93), plenti III (26.42 ± 0.42), and the control group (8.79 ± 2.29) (P<0.001). This study showed a decreasing trend in survival with increasing doses. Suppression of anti-apoptotic genes, including XIAP, MCL1, Birc3, and REL, enhanced radiosensitivity by increasing the expression of hsa-miR-7-5p in the PC3 and LNCaP cell lines. Hsa-miR-7-5p is a miRNA that can suppress the expression of anti-apoptotic genes and thus plays an essential role in the process of cell apoptosis. Targeting genes that are associated with apoptosis could potentially enhance the efficacy of treatments for patients with prostate cancer.