Delivering nucleic acid therapeutics across cell membranes is a significant challenge. Cell-penetrating peptides (CPPs) containing arginine (R), tryptophan (W), and histidine (H) show promise for siRNA delivery. To improve siRNA delivery and silence a model STAT3 gene, we hypothesized that oleyl acylation to CPPs, specifically (WRH)n, would enhance STAT3 silencing efficiency in breast and ovarian cancer cells. Using Fmoc/tBu solid-phase peptide chemistry, we synthesized, purified, and characterized the oleyl-conjugated (WRH)n (n = 1-4) peptides. The peptide/siRNA complexes were non-cytotoxic at N/P 40 (~20 μM) against MDA-MB-231, MCF-7, SK-OV-3, and HEK-293 cells after 72 h incubation. All peptide/siRNA complexes showed serum stability at N/P ≥ 40. The synthesized conjugates, with a diameter of <100 nm, formed nano-complexes with siRNA and exhibited a stable range of zeta potential values (13-18 mV at N/P = 40). Confocal microscopy and flow cytometry analysis provided qualitative and quantitative evidence of a successful cellular internalization of siRNA. The peptides oleyl-(WRH)3 and oleyl-(WRH)4 showed ~60% and ~75% cellular uptake of siRNA, respectively, in both MDA-MB-231 and SK-OV-3 cells. Western blot analysis of oleyl-(WRH)4 demonstrated effective silencing of the STAT-3 gene, with ~75% silencing in MDA-MB-231 cells and ~45% in SK-OV-3 cells.

UNASSIGNED: During breast cancer treatment, approximately half of the patients are prescribed psychotropic medication, such as selective serotonin reuptake inhibitors (SSRIs). Escitalopram oxalate is an SSRI used as an antidepressant.
UNASSIGNED: In this study, by creating a breast cancer microenvironment with THP-1, MCF-7 and MDA-MB-231 breast cancer co-culture models were created.
UNASSIGNED: MCF-7, MDA-MB-231, and THP-1 cell lines to determine the concentration range of the cytotoxic effect of escitalopram oxalate MTS and MTT test were used. IC50 values were determined by the xCELLigence real-time cell analysis (RTCA) system. Apoptotic activities and cytokine levels were determined by flow cytometry.
UNASSIGNED: In the xCELLigence real-time analysis made according to the results, the IC50 value of escitalopram oxalate was measured as 13.7 μM for MCF-7 and 10.9 μM for MDA-MB-231. The IC50 value was measured as 54.6 μM for MCF-7 and 58.4 μM for MDA-MB-231 in xCELLigence analysis with tamoxifen. According to the MTS test results, the IC50 value of tamoxifen for THP-1 was 92.03 μM and the IC50 value for escitalopram oxalate was 95.32 μM. In the co-culture model, the immunological effects of escitalopram oxalate on MCF-7 cells were 2.8%, 11.1%, 15.6%, 10.6%, and 12.1% for interleukin (IL)-1β, IL-6, IL-8, IL-10, and TNF-α, respectively, while MDA effects on MB-231 cells, respectively, were 2.1%, 15.9%, 16.2%, 8.8%, and 11.8%.
UNASSIGNED: According to the results obtained, it was concluded that the immunological effects of escitalopram oxalate are more effective than tamoxifen and that it can be used as an adjunctive agent in breast cancer treatment.

Background Enhancing chemotherapy efficacy is crucial in breast cancer treatment. This study examines the synergistic effects of paclitaxel, a common chemotherapeutic drug, and Cluster of differentiation 73 (cd73) gene suppression via siRNA on MDA-MB-231 breast cancer cells. Methods MDA-MB-231 cells were transfected with CD73 siRNA and treated with paclitaxel. Cell viability, apoptosis, and migration were assessed by using MTT assays, Annexin V-FITC/PI staining, and wound healing assays, respectively, with flow cytometry analyzing cell cycle distribution. Results The combination of CD73 siRNA and paclitaxel significantly reduced cell viability, lowering paclitaxel\'s IC50 from 14.73 μg/mL to 8.471 μg/mL, indicating enhanced drug sensitivity. Apoptosis rates increased with the combination treatment, while cell migration was significantly inhibited. Flow cytometry revealed cell cycle arrest in the Sub-G1 and G2-M phases. Conclusion These findings suggest that cd73 gene suppression enhances paclitaxel\'s cytotoxic effects, promoting apoptosis and inhibiting cell migration in MDA-MB-231 breast cancer cell line. This combined strategy shows promise for improving breast cancer treatment outcomes by increasing the efficacy of existing chemotherapeutic regimens, warranting further research to explore its potential clinical applications and effectiveness in other breast cancer cell lines and models.

Spheroids have become principal three-dimensional models to study cancer, developmental processes, and drug efficacy. Single-cell analysis techniques have emerged as ideal tools to gauge the complexity of cellular responses in these models. However, the single-cell quantitative assessment based on 3D-microscopic data of the subcellular distribution of fluorescence markers, such as the nuclear/cytoplasm ratio of transcription factors, has largely remained elusive. For spheroid generation, ultra-low attachment plates are noteworthy due to their simplicity, compatibility with automation, and experimental and commercial accessibility. However, it is unknown whether and to what degree the plate type impacts spheroid formation and biology. This study developed a novel AI-based pipeline for the analysis of 3D-confocal data of optically cleared large spheroids at the wholemount, single-cell, and sub-cellular levels. To identify relevant samples for the pipeline, automated brightfield microscopy was employed to systematically compare the size and eccentricity of spheroids formed in six different plate types using four distinct human cell lines. This showed that all plate types exhibited similar spheroid-forming capabilities and the gross patterns of growth or shrinkage during 4 days after seeding were comparable. Yet, size and eccentricity varied systematically among specific cell lines and plate types. Based on this prescreen, spheroids of HaCaT keratinocytes and HT-29 cancer cells were further assessed. In HaCaT spheroids, the in-depth analysis revealed a correlation between spheroid size, cell proliferation, and the nuclear/cytoplasm ratio of the transcriptional coactivator, YAP1, as well as an inverse correlation with respect to cell differentiation. These findings, yielded with a spheroid model and at a single-cell level, corroborate earlier concepts of the role of YAP1 in cell proliferation and differentiation of keratinocytes in human skin. Further, the results show that the plate type may influence the outcome of experimental campaigns and that it is advisable to scan different plate types for the optimal configuration during a specific investigation.

To investigate the effects of higher cellular stanniocalcin 2 (STC2) on suppressing the migration and invasion but promoting the apoptosis of triple-negative breast cancer (TNBC). STC2 in TNBC and the para-carcinoma tissues were analyzed by immunohistochemistry (IHC), while the mRNA level was measured by qPCR. Over-expressing or silencing STC2 was established in MDA-MB-231 cells. Epithelial mesenchymal transition (EMT) related proteins, cell migration, invasion, proliferation and apoptosis were detected. MDA-MB-231 with over-expressing or silencing STC2 were injected into nude mice to formatting tumors, and then EMT related proteins were measured by IHC. Lower STC2 expressed in TNBC tissues than in the para-carcinoma tissues. Silencing STC2 promoted EMT of TNBC cell MDA-MB-231, as well as cell migration, invasion and proliferation, but suppressed MDA-MB-231 apoptosis, while over-expressing STC2 had the opposite results, which might be related to PKC/PI3K/AKT/mTOR pathway. STC2 was the protective gene in TNBC, by suppressing migration and invasion to inhibit MDA-MB-231 cell EMT but promote cell apoptosis, in order to suppress TNBC progression.

A new imidazolium ionic liquid (IL) halide conjugated with dimethylcardamonin (DMC, 1), namely [Bbim]Br-DMC (3), was synthesised to improve the biological activity of the natural chalcone. DMC was isolated from seeds of Syzygium nervosum A. Cunn. ex DC. which was an effective anti-breast cancer agent. The compound 1 and 3 showed anticancer activity in MDA-MB-231 cells with IC50 values of 14.54 ± 0.99 μM and 7.40 ± 0.15 μM, respectively. MTT assay showed that compound 3 had cytotoxic effect at least two-fold greater than compound 1 but was low toxic to normal cells of Hs 578Bst. After 48 h, compound 3 at concentration of IC50 value inhibited the proliferation and induced morphological changes of MDA-MB-231 cells in a time-dependent manner. The cell cycle profile also showed that compound 3 exerted anti-proliferation activity with the cell cycle arrest at G0/G1 phase and compound 3 also induced apoptosis and reduced mitochondrial membrane potential in MDA-MB-231 cells in a dose-dependent manner. In gene expression assay, compound 3 up-regulated pro-apoptotic genes such as Bax and p53 and suppressed anti-apoptotic Bcl-2 whereas there was no effect on DNA repair gene such as PARP1. The Bax/Bcl-2 ratio was significantly increased after treated with compound 3. In the molecular docking study, the interactions between compound 3 and B-DNA structure in the minor groove region via hydrogen bonds was reported. In conclusion, [Bbim]Br-DMC or compound 3 is a potential candidate to induce apoptosis and inhibits proliferation via cell cycle arrest and decreases mitochondrial membrane of triple-negative breast cancer MDA-MB-231 cells.

Antimicrobial peptides, such as nisin, are proposed as promising agents for cancer treatment. While glycation has been recognized as an effective method for enhancing various physicochemical properties of nisin, its anticancer effects remain unexplored. Therefore, we aimed to assess the anticancer potential of glycated nisin against MDA-MB-231 cells. The MDA-MB cells were treated with increasing concentrations of nisin and glycated nisin for 24, 48, and 72 h. The IC50 values for nisin were higher than those for glycated nisin. Glycated nisin at concentrations of 20 and 40 µg/mL decreased cell viability more than nisin at the same concentrations. The rate of apoptosis in the group treated with 20 µg/mL of nisin was lower compared to other treatment groups, and no significant difference in apoptosis rates was observed at different time points (p > 0.05). However, in the glycated nisin groups with concentrations of 10, 20, and 40 µg/mL, the level of apoptosis was very high after 24 h (73-81% of cells undergoing apoptosis). Overall, our study suggests that glycated nisin exhibits stronger cytotoxic effects on MDA-MB-231 cells, primarily involving the induction of apoptosis. This indicates its potential utilization as an alternative approach to address the issue of drug resistance in cancer cells.

OBJECTIVE: Lipids are essential for energy production, signaling, and membrane formation, hence increased lipid metabolism may lead to cancer growth. 4-cholesten-3-one (4Cone), a sterol metabolite, has various biological activities, including the inhibition of cancer growth. This study examined whether 4Cone could change the lipid profile of triple-negative breast cancer cells (MDA-MB-231) and whether in combination with the anti-cancer chemotherapy docetaxel (TXT) could further reduce cancer aggressiveness.
METHODS: The effect of 4Cone, TXT, or their combination (4Cone/TXT) on migration and proliferation was examined utilizing the wound healing and MTT assays. The expression of the lipogenesis-related enzymes was assessed using RT-qPCR and lipid profile was examined using mass spectrometry.
RESULTS: 4Cone and TXT individually reduced cell viability and migration of MDA-MB-231 cancer cells; however, their combination (4Cone/TXT) had a greater impact on both attributes. All treated cells showed markedly decreased levels of the multidrug resistance enzyme PGP as well as the lipogenic enzymes FASN, ACC1, SCD1, HMGCR, and DGAT. Furthermore, lipid fingerprints were markedly different in treated cells compared with the untreated group. 4Cone increased the percentage of sphingomyelin (SM) while it decreased the percentage of ceramide (Cer); 4Cone in conjunction with TXT had the reverse effect. Triglyceride levels were reduced in 4Cone- and 4Cone/TXT-treated cells, but interestingly, they increased in TXT-treated cells. Additionally, treated cancer cells exhibited changes in glycerophospholipid subclasses.
CONCLUSIONS: 4Cone alone or in combination with TXT alters the lipid profile by reducing a key lipogenic enzyme, resulting in the inhibition of cell proliferation and migration.

UNASSIGNED: Metastasis is responsible for 90% of cancer-related deaths worldwide. However, the potential inhibitory effects of metastasis by various anticancer drugs have been left largely unexplored. Existing preclinical models primarily focus on antiproliferative agents on the primary tumor to halt the cancer growth but not in metastasis. Unlike primary tumors, metastasis requires cancer cells to exert sufficient cellular traction force through the actomyosin machinery to migrate away from the primary tumor site. Therefore, we seek to explore the potential of cellular traction force as a novel readout for screening drugs that target cancer metastasis.
UNASSIGNED: In vitro models of invasive and non-invasive breast cancer were first established using MDA-MB-231 and MCF-7 cell lines, respectively. Cellular morphology was characterized, revealing spindle-like morphology in MDA-MB-231 and spherical morphology in MCF-7 cells. The baseline cellular traction force was quantified using the Traction force Microscopy technique. Cisplatin, a paradigm antimetastatic drug, and 5-Fluorouracil (5FU), a non-antimetastatic drug, were selected to evaluate the potential of cellular traction force as a drug testing readout for the in vitro cancer metastasis.
UNASSIGNED: MDA-MB-231 cells exhibited significantly higher baseline cellular traction force compared to MCF-7 cells. Treatment with Cisplatin, an antimetastatic drug, and 5-Fluorouracil (5FU), a non-antimetastatic drug, demonstrated distinct effects on cellular traction force in MDA-MB-231 but not in MCF-7 cells. These findings correlate with the invasive potential observed in the two models.
UNASSIGNED: Cellular traction force emerges as a promising metric for evaluating drug efficacy in inhibiting cancer metastasis using in vitro models. This approach could enhance the screening and development of novel anti-metastatic therapies, addressing a critical gap in current anticancer drug research.

UNASSIGNED: The resistant and aggressive nature of triple-negative breast cancer (TNBC) renders it mostly incurable even following extensive multimodal treatment. Therefore, more studies are required to understand the underlying molecular mechanisms of its pathogenesis. SIRT1 is a class III histone deacetylase NAD + -dependent enzyme that is interlinked in tumor progression, apoptosis, metastasis, and other mechanisms of tumorigenesis, while DNA polymerase delta 1 (POLD1) functions as a gene coding for p125, which plays an important role in genome stability and DNA replication.
UNASSIGNED: We aimed to investigate the downstream signaling pathway of EX-527, a potent and selective SIRT1 inhibitor, in MDA-MB-231 breast cancer cell lines, and the crosstalk between SIRT1 and POLD1, which is essential for the activities of polymerase δ.
UNASSIGNED: The antiproliferative and apoptotic effects of EX-527 on MDA-MB-231 cells were assessed by MTT and annexin V/PI double staining assays. Migration and invasion activity of MDA-MB-231 cells were assessed by wound-healing scratch and transwell assays. Protein expressions were examined using Western Blot analysis.
UNASSIGNED: MDA-MB-231 cells treatment with IC50 values of 45.3 μM EX-527 significantly suppressed cell proliferation and induced apoptosis by down-regulating SIRT1. Also, it significantly repressed migration and invasion of MDA-MB-231 cells as evaluated by wound healing and transwell invasion assays. Western blot results showed that decreased expression of SIRT1 is positively correlated with expression of p53 along with down-regulating POLD1.
UNASSIGNED: SIRT1 could have an oncogenic role in breast cancer development and progression via activating POLD1. These conclusions present new insights into the underlying mechanisms of TNBC.