Beauvericin, produced by Fusarium oxysporum inhibits bisphenol A-induced proliferation of human breast cancer cell line by regulating ERα/p38 pathway

Beauvericin (BEA) is a cyclic depsipeptide secondary metabolite of Fusarium species. It causes chemical hazards in food products and exists in an environment containing soil and various food types. On the other hand, the purified BEA has various biological activities and is regarded as a potential candidate for pharmaceutical research. This study was performed to assess the anti-proliferation activity of BEA against human breast cancer cells by regulating the estrogen receptor-alpha (ERα)/p38 pathway. TA and BA assays verified that BEA is a completed ER antagonist. Additionally, BEA suppressed cell proliferation in the anti-proliferation assay involving ER-positive human breast cancer cells co-treated with BPA and BEA. In respect to an anti-proliferation activity, the BPA-induced phosphorylation of p38 protein was inhibited in the presence of BEA. These results suggested that BEA exerts inhibitory potentials on endocrine disrupting effect and possibly acts as a natural therapeutic material for human estrogen hormonal health.

Caveolin-Mediated Internalization of Fmoc-FF Nanogels in Breast Cancer Cell Lines

INTRODUCTION

Hydrogel nanoparticles, also known as nanogels (NGs), have been recently proposed as alternative supramolecular vehicles for the delivery of biologically relevant molecules like anticancer drugs and contrast agents. The inner compartment of peptide based NGs can be opportunely modified according to the chemical features of the cargo, thus improving its loading and release. A full understanding of the intracellular mechanism involved in nanogel uptake by cancer cells and tissues would further contribute to the potential diagnostic and clinical applications of these nanocarriers, allowing the fine tuning of their selectivity, potency, and activity. The structural characterization of nanogels were assessed by Dynamic Light Scattering (DLS) and Nanoparticles Tracking Analysis (NTA) analysis. Cells viability of Fmoc-FF nanogels was evaluated by MTT assay on six breast cancer cell lines at different incubation times (24, 48, and 72 h) and peptide concentrations (in the range 6.25 × 10^-4 ÷ 5·10^-3 × wt%). The cell cycle and mechanisms involved in Fmoc-FF nanogels intracellular uptake were evaluated using flow cytometry and confocal analysis, respectively. Fmoc-FF nanogels, endowed with a diameter of ~130 nm and a zeta potential of ~-20.0/-25.0 mV, enter cancer cells via caveolae, mostly those responsible for albumin uptake. The specificity of the machinery used by Fmoc-FF nanogels confers a selectivity toward cancer cell lines overexpressing the protein caveolin1 and efficiently performing caveolae-mediated endocytosis.

Duplex Phenotype Detection and Targeting of Breast Cancer Cells Using Nanotube Nanoprobes and Raman Imaging

We designed, synthesized, and characterized a Raman nanoprobe made of dye-sensitized single-walled carbon nanotubes (SWCNTs) that can selectively target biomarkers of breast cancer cells. The nanoprobe is composed of Raman-active dyes encapsulated inside a SWCNT, whose surface is covalently grafted with poly(ethylene glycol) (PEG) at a density of ∼0.7% per carbon. Using α-sexithiophene- and β-carotene-derived nanoprobes covalently bound to an antibody, either anti-E-cadherin (E-cad) or anti-keratin-19 (KRT19), we prepared two distinct nanoprobes that specifically recognize biomarkers on breast cancer cells. Immunogold experiments and transmission electron microscopy (TEM) images are first used to guide the synthesis protocol for higher PEG-antibody attachment and biomolecule loading capacity. The duplex of nanoprobes was then applied to target E-cad and KRT19 biomarkers in T47D and MDA-MB-231 breast cancer cell lines. Hyperspectral imaging of specific Raman bands allows for simultaneous detection of this nanoprobe duplex on target cells without the need for additional filters or subsequent incubation steps. Our results confirm the high reproducibility of the nanoprobe design for duplex detection and highlight the potential of Raman imaging for advanced biomedical applications in oncology.

Comparative phytochemical composition, oleuropein quantification, antioxidant and cytotoxic properties of Olea europaea L. leaves

In the present research, oleuropein (OLE) contents from two Saudi Arabian wild olive trees (Olea europaea L.) leaves (O1 and O2), were collected from two nearby geographical sites differing in altitudes, and were determined via UHPLC-MS analysis. Moreover, total bioactive contents, antioxidant, and cytotoxicity (against MCF-7 and MDA-MB-231 cells) potential were also evaluated. The sample (O2) was found to contain significantly (p < 0.05) higher OLE content (4.13 ± 1.0 mg/g DW) compared with the sample (O1) having OLE content (3.63 ± 1.1 mg/g DW). A similar trend was observed regarding total bioactive contents and antioxidant potential. However, both samples exhibited low cytotoxicity against tested cell lines. Furthermore, with hierarchical cluster analysis that compared the results of our samples (O1 and O2) to other samples reported in the literature, it was found that the variance in OLE content and biological activities from Al Baha region leaves had a resemblance to other reported superior cultivars.

Dalpiciclib partially abrogates ER signaling activation induced by pyrotinib in HER2+HR+ breast cancer

Recent evidences from clinical trials (NCT04486911) revealed that the combination of pyrotinib, letrozole, and dalpiciclib exerted optimistic therapeutic effect in treating HER2⁺HR⁺ breast cancer; however, the underlying molecular mechanism remained elusive. Through the drug sensitivity test, the drug combination efficacy of pyrotinib, tamoxifen, and dalpiciclib to BT474 cells was tested. The underlying molecular mechanisms were investigated using immunofluorescence, Western blot analysis, immunohistochemical staining, and cell cycle analysis. Potential risk factor that may indicate the responsiveness to drug treatment in HER2⁺/HR⁺ breast cancer was identified using RNA-sequence and evaluated using immunohistochemical staining and in vivo drug susceptibility test. We found that pyrotinib combined with dalpiciclib exerted better cytotoxic efficacy than pyrotinib combined with tamoxifen in BT474 cells. Degradation of HER2 could enhance ER nuclear transportation, activating ER signaling pathway in BT474 cells, whereas dalpiciclib could partially abrogate this process. This may be the underlying mechanism by which combination of pyrotinib, tamoxifen, and dalpiciclib exerted best cytotoxic effect. Furthermore, CALML5 was revealed to be a risk factor in the treatment of HER2⁺/HR⁺ breast cancer and the usage of dalpiciclib might overcome the drug resistance to pyrotinib + tamoxifen due to CALML5 expression. Our study provided evidence that the usage of dalpiciclib in the treatment of HER2⁺/HR⁺ breast cancer could partially abrogate the estrogen signaling pathway activation caused by anti-HER2 therapy and revealed that CALML5 could serve as a risk factor in the treatment of HER2⁺/HR⁺ breast cancer.

L-asparaginase from human breast milk Lactobacillus reuteri induces apoptosis using therapeutic targets Caspase-8 and Caspase-9 in breast cancer cell line

BACKGROUND

Breast cancer is the most fatal type of cancer in women worldwide. Many chemotherapeutics targeted breast cancer however, they have frightening side effects. One method of controlling cancer cell growth is targeting apoptosis.

OBJECTIVE

This study aimed to induce apoptosis in breast cancer cells by purifying L-asparaginase from human breast milk Lactobacillus reuteri isolates via inhibition of Caspases 8 and 9.

METHODS

The best L. reuteri isolates producing L-asparagine with the highest enzyme activity were identified from human breast milk and chosen for L-asparaginase purification. The MTT cell viability assay used for measure the toxicity of the enzyme. Breast cancer cell line was used to study the effect of the enzyme on the caspase 8 and caspase 9 gene expression.

RESULTS

The MTT cell viability assay showed the inhibition rates ranged between 30% and 80%, of cell death, occurred when 3.125, 6.25, 12.5, 25, 50, and 100 μg/ml of the enzyme used and IC50 was 4.305 μg/ml. The breast cell lines were treated with the enzyme at a concentration of IC50 value. The Cas8 and Cas9 genes expression in L-asparagine treated breast cancer cell line at a concentration of IC50 value were upregulated (the fold of gene expression are 2.071 and 1.197 respectively).

CONCLUSIONS

Breast milk L. reuteri L-asparaginase induces apoptosis via Cas8 and Cas9 upregulation in the breast cancer cell line. L. reuteri L-asparaginase treatment may be the hopeful approach for the management of breast cancer. Furthermore, the results may highlight the fact that the presence of L-asparaginase-producing L. reuteri isolates in human breast milk may aid in breast cancer improvement or even prevention.

The effect of a bis-structured Schiff base on apoptosis, cytotoxicity, and DNA damage of breast cancer cells

Developing new anticancer agents are crucial for cancer treatment. Antiproliferative activity of L1H as a bis-structured Schiff base was subjected to preliminary research in eight different kinds of cell lines by the cell viability method using different concentrations to determine their inhibitory concentration. L1H demonstrated the highest cytotoxicity in human breast cancer cell line MCF-7. In this perspective, the MCF-7 cell line was cultured for the examination of different molecular techniques, including MTT, apoptosis analysis by enzyme-linked immunosorbent assay (ELISA), and comet assay. Moreover, the DNA ladder, acridine orange/ethidium bromide as another apoptotic cell analysis, markers of oxidative stress, and total antioxidant status, total thiol, and GSH as nonenzymatic antioxidants assay were conducted. The above techniques have proven that L1H is a growth inhibitor effect when compared to cisplatin as a positive control in human breast cancer cells, especially those affected by L1H. The findings clearly show that L1H evaluated in MCF-7 cell lines causes rising or induced apoptosis, DNA damage, diminished antioxidant status against the increase of oxidized protein, and prevents cell proliferation. Manifold evidence supported our hypothesis that L1H has a potential therapeutically improved effect against the MCF-7 cell line, and then without a doubt is a suitable candidate drug for investigating cancers next.

Vanillin extracted from proso and barnyard millets induces cell cycle inhibition and apoptotic cell death in MCF-7 cell line

Context

Consuming whole grain food has been motivated due to numerous health benefits arising from their bioactive components.

Aims

This study aims to study whether the active compound extracted from Proso and Barnyard millets inhibits cell proliferation and induces apoptotic cell death in MCF-7 cell line.

Materials and Methods

Cell proliferative effect was assessed by 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay using MCF-7 cell line. Cytotoxicity was determined by release of lactate dehydrogenase (LDH) enzyme from cells. Apoptotic morphological changes in MCF-7 cells were observe under fluorescence microscope using double staining of Hoeschst 33342/propidium iodide (PI). Induction of apoptosis was analyzed using Annexin V-fluorescein isothiocyanate/PI through flow cytometry.

Results

In this study, cell proliferative effect of the bioactive compounds from proso millet (Compound 1) and barnyard millet (Compound 2) was evaluated using MCF-7 cell line. Both the compounds significantly inhibited the proliferation of MCF-7 cells after treated with 250 μg/ml and 1000 μg/ml concentration for 48 h. Cytotoxic activity of compounds was assessed by the release of LDH showed that these extracted compounds were not toxic to the cells. Apoptosis was confirmed by Hoechst 33,342/PI dual-staining, Annexin V-FTIC/PI staining, and flow cytometry results of cell cycle analysis shows that there was a significant cell arrest in the G0/G1 phase and increased the apoptotic cells in sub-G0 phase in a dose-dependent manner.

Conclusions

This study suggests that the extracted vanillin compound from these millets have effectively induced apoptotic cell death in breast cancer cell line.

Discovery of a novel potentially transforming somatic mutation in CSF2RB gene in breast cancer

The colony stimulating factor 2 receptor subunit beta (CSF2RB) is the common signaling subunit of the cytokine receptors for IL-3, IL-5, and GM-CSF. Several studies have shown that spontaneous and random mutants of CSF2RB can lead to ligand independence in vitro. To date, no report(s) have been shown for the presence of potentially transforming and oncogenic CSF2RB mutation(s) clinically in cancer patients until the first reported case of a leukemia patient in 2016 harboring a germline-activating mutation (R461C). We combined exome sequencing, pathway analyses, and functional assays to identify novel somatic mutations in KAIMRC1 cells and breast tumor specimen. The patient's peripheral blood mononuclear cell (PBMC) exome served as a germline control in the identification of somatic mutations. Here, we report the discovery of a novel potentially transforming and oncogenic somatic mutation (S230I) in the CSF2RB gene of a breast cancer patient and the cell line, KAIMRC1 established from her breast tumor tissue. KAIMRC1 cells are immortalized and shown to survive and proliferate in ligand starvation condition. Immunoblot analysis showed that mutant CSF2RB signals through JAK2/STAT and PI3K/mTOR pathways in ligand starvation conditions. Screening a small molecule kinase inhibitor library revealed potent JAK2 inhibitors against KAIMRC1 cells. We, for the first time, identified a somatic, potentially transforming, and oncogenic CSF2RB mutation (S230I) in breast cancer patients that seem to be an actionable mutation leading to the development of new therapeutics for breast cancer.

Identification of Novel Endogenous Controls for qPCR Normalization in SK-BR-3 Breast Cancer Cell Line

Normalization of gene expression using internal controls or reference genes (RGs) has been the method of choice for standardizing the technical variations in reverse transcription quantitative polymerase chain reactions (RT-qPCR). Conventionally, ACTB and GAPDH have been used as reference genes despite evidence from literature discouraging their use. Hence, in the present study we identified and investigated novel reference genes in SK-BR-3, an HER2-enriched breast cancer cell line. Transcriptomic data of 82 HER2-E breast cancer samples from TCGA database were analyzed to identify twelve novel genes with stable expression. Additionally, thirteen RGs from the literature were analyzed. The expression variations of the candidate genes were studied over five successive passages (p) in two parallel cultures S1 and S2 and in acute and chronic hypoxia using various algorithms. Finally, the most stable RGs were selected and validated for normalization of the expression of three genes of interest (GOIs) in normoxia and hypoxia. Our results indicate that HSP90AB1, DAD1, PFN1 and PUM1 can be used in any combination of three (triplets) for optimizing intra- and inter-assay gene expression differences in the SK-BR-3 cell line. Additionally, we discourage the use of conventional RGs (ACTB, GAPDH, RPL13A, RNA18S and RNA28S) as internal controls for RT-qPCR in SK-BR-3 cell line.

Chitosan-Coated Halloysite Nanotubes As Vehicle for Controlled Drug Delivery to MCF-7 Cancer Cells In Vitro

The aim of the work is to improve the release properties of curcumin onto human breast cancer cell lines using coated halloysite nanotubes (HNTs) with chitosan as a polycation. A loading efficiency of 70.2% (w/w) was attained for loading 4.9 mg of the drug into 0.204 g bed volume of HNTs using the vacuum suction method. Results acquired from Brunauer-Emmett-Teller (BET), Fourier-transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), scanning electron spectroscopy (SEM), zeta potential, and thermogravimetric analysis (TGA) indicated the presence of the drug and the biopolymer in and around the nanotubes. The release properties of drug-loaded HNTs (DLHNTs) and chitosan-coated drug-loaded HNTs (DLHNTs-CH) were evaluated. The release percentages of DLHNTs and DLHNTs-CH after 6 h were 50.7 and 37%, respectively. Based on the correlation coefficients obtained by fitting the release nature of curcumin from the two samples, the Korsmeyer-Peppas model was found to be the best-fitted model. In vitro cell viability studies were carried out on the human breast cancer cell line MCF-7, using the MTT and trypan blue exclusion assays. Prior to the Trypan blue assay, the IC₅₀ of curcumin was determined to be ~30 µM. After 24 h of incubation, the recorded cell viability values were 94, 68, 57, and 51% for HNTs, DLHNTs-CH, DLHNTs, and curcumin, respectively. In comparison to the release studies, it could be deducted that sustained lethal doses of curcumin were released from the DLHNTs-CH within the same time. It is concluded from this work that the "burst release" of naked drugs could be slowly administered using chitosan-coated HNTs as potential drug carriers.

Facile synthesis of C6-substituted benz[4,5]imidazo[1,2-a]quinoxaline derivatives and their anticancer evaluation

Cancer remains a leading cause of death worldwide, resulting in continuous efforts to discover and develop highly efficacious anticancer drugs. High-throughput screening of heterocyclic compound libraries is one of the promising approaches that provided several new lead molecules with a novel mechanism of action. On the basis of the promising anticancer potential of imidazoquinoxaline as well as the structurally similar imidazoquinoline-derived scaffold, we prepared a set of C6-substituted benzimidazo[1,2-a]quinoxaline derivatives via two novel synthetic routes using commercially available starting materials, with good to excellent yields and evaluated their anticancer activity against the NCI-60 cancer cell lines. The one-dose (10 µM) anticancer screening of the synthesized compounds in the NCI-60 cell line panel revealed that the substituents have a significant role in the activity. In particular, the indole (7f), imidazole (7g), and benzimidazole (7h) derivatives showed significant activity against the triple-negative breast cancer cell line, MDA-MB-468. The lead compounds also exhibited notable IC₅₀ values against another breast cancer cell line, MCF-7. Furthermore, it was observed that these compounds were relatively nontoxic to normal cell lines: HEK293 (human embryonic kidney cell line) and MCF12A (nontumorigenic human breast epithelial cell line). The IC₅₀ values against healthy cells were at least 5- to 11-fold higher, offering a new class of heterocycles that can be further developed as promising therapeutics for cancer treatment.

[Exploration of organoid in breast cancer related research]

Breast cancer is the most common cancer in women. At present, the in vivo model and traditional cell culture are mainly used in breast cancer researches. However, as high as 90% clinical trials are failed for drugs explored by the above two methods, due to the inherent species differences between humans and animals, as well as the differences in the tissue structure between organs and cells. Therefore, organoid three-dimensional culture is emerging. As a new tumor research model, organoid, a three-dimensional cell complex with spatial structure, has broad application prospects, such as precision medicine, organ transplantation, establishment of refractory disease model, gene therapy and drug research and development. Therefore, organoid is considered as one of the ideal carriers for life science research in the future. Breast cancer, a heterogeneous disease with complex phenotypes, has a low survival rate. Breast cancer organoid can reproduce many key features of human breast cancer, thus, the construction of organoid biological library of breast cancer will provide a new platform for studying the occurrence, development, metastasis and drug resistance mechanism of breast cancer. In this review, we systematically introduce the culture conditions of organoids and their application in breast cancer related research, and the application prospect of organoids.

Induction of Biosynthetic Genes Related to Rosmarinic Acid in Plant Callus Culture and Antiproliferative Activity Against Breast Cancer Cell Line

BACKGROUND AND OBJECTIVE

Rosmarinic acid is considered as one of the most important secondary metabolites in medicinal plants especially of family Lamiaceae. Rosmarinic acid can prevent both the tumor initiation and promotion stages of carcinogenesis. The aim of current study was to evaluate the antiproliferative effects of Hyssopus officinalis and Thymus vulgaris callus crude extracts contained rosmarinic acid on breast cancer cells with correlation to phenylpropanoid biosynthetic pathway genes expression.

MATERIALS AND METHODS

Calli of both plants were maintained on Murashige and Skoog medium supplemented with kinetin and 2,4-D. Rosmarinic acid was determined spectrophotometrically in both seed-germinated plants (control) and callus tissues. Transcriptional profiling of rosmarinic acid pathway genes was performed with RT-PCR system. The human breast cancer cell line MCF-7 was treated with different levels of crude extracts at different time intervals in order to show their effects on the cell proliferation using a cell viability colorimetric assay (MTT).

RESULTS

The results showed a significant increase of rosmarinic acid content up to 6.5% in callus compared to control. The transcriptional profile of the selected rosmarinic acid genes in callus tissues indicated significant effects on the rosmarinic acid content in both genotypes. T. vulgaris (90 μg mL-1) and H. officinalis (150 μg mL-1) callus extracts had exhibited highest reduction in the cell MCF-7 viability after 48 h of exposure.

CONCLUSION

It was concluded that rosmarinic acid production increased in callus tissue, showed the higher gene expression levels and remarkably inhibited growth of human breast cancer cell line.

Functional design of pH-responsive folate-targeted polymer-coated gold nanoparticles for drug delivery and in vivo therapy in breast cancer

BACKGROUND

Curcumin has been widely used owing to its various medicinal properties including antitumor effects. However, its clinical application is limited by its instability, poor solubility and low bioavailability. Folic acid (FA)-functionalized nanoformulations may enhance the sustained release of an anticancer drug (curcumin) by tumor-specific targeting to improve therapeutic benefit. This study aims to design a nanoconjugate (NC) comprised of folate-curcumin-loaded gold-polyvinylpyrrolidone nanoparticles (FA-CurAu-PVP NPs) for targeted delivery in breast cancer model systems.

METHODS

We developed curcumin-loaded FA-functionalized Au-PVP NCs by layer-by-layer assembly. The folic acid-curcumin Au-PVP NCs (FA-CurAu-PVP NCs) were characterized by ultraviolet-visible spectra, Fourier transform infrared spectroscopy, X-ray powder diffraction and thermogravimetric analysis. In vitro anticancer and antimigratory effects of NCs were examined by performing MTT and wound migration assays. The in vivo antitumor efficacy of NCs was investigated using a preclinical breast cancer orthotopic mouse model.

RESULTS

Curcumin (40 µg/mL) was loaded along with conjugation of folate onto Au-PVP NPs to form FA-CurAu-PVP NCs. The size and charge of the NCs were increased gradually through layer-by-layer assembly and showed 80% release of curcumin at acidic pH. The NC did not show aggregation when incubated with human serum and mimicked an intrinsic peroxidase-like property in the presence of 3,3',5,5'-tetramethylbenzidine substrate. The MTT data using these NCs showed efficient anticancer activity at lower doses in estrogen/progesterone receptor (ER/PR)-negative cells compared with ER/PR-positive cells. Furthermore, the NCs did not show cytotoxicity at the investigated concentration in human breast epithelial and mouse fibroblast cell lines. They showed inhibitory effects on cell migration and high antitumor efficacy in in vivo analysis.

CONCLUSION

These results suggest that folate-based tumor targeting using CurAu-PVP NCs is a promising approach for tumor-specific therapy of breast cancer without harming normal cells.

Revealing the Biological Attributes of N-Glycan Isomers in Breast Cancer Brain Metastasis Using Porous Graphitic Carbon (PGC) Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)

Breast cancer is a leading cancer in women and is considered to be the second-most common metastatic cancer following lung cancer. An estimated 10-16% of breast cancer patients are suffering from brain metastasis, and the diagnostic cases of breast cancer brain metastasis are increasing. Nevertheless, the mechanisms behind this process are still unclear. Aberrant glycosylation has been proved to be related to many diseases and cancer metastasis. However, studies of N-glycan isomer function in breast cancer brain metastasis are limited. In this study, the expressions of N-glycan isomers derived from five breast cancer cell lines and one brain cancer cell line were investigated and compared to a brain-seeking cell line, 231BR, to acquire a better understanding of the role glycan isomers play in breast cancer brain metastasis. The high temperature nanoPGC-LC-MS/MS achieved an efficient isomeric separation and permitted the identification and quantitation of 144 isomers from 50 N-glycan compositions. There were significant expression alterations of these glycan isomers among the different breast cancer cell lines. The increase of total glycan abundance and sialylation level were observed to be associated with breast cancer invasion. With regard to individual isomers, the greatest number of sialylated isomers was observed along with significant expression alterations in 231BR, suggesting a relationship between glycan sialylation and breast cancer brain metastasis. Furthermore, the increase of the α2,6-sialylation level in 231BR likely contributes to the passage of breast cancer cells through the blood-brain barrier, thus facilitating breast cancer brain metastasis. Meanwhile, the upregulation of highly sialylated glycan isomers with α2,6-linked sialic acids were found to be associated with breast cancer metastasis. This investigation of glycan isomer expressions, especially the unique isomeric expression in brain-seeking cell line 231BR, provides new information toward understanding the potential roles glycan isomers play during breast cancer metastasis and more clues for a deeper insight of this bioprocess.

Complete Disaggregation of MCF-7-derived Breast Tumour Spheroids with Very Low Concentrations of α-Mangostin Loaded in CD44 Thioaptamer-tagged Nanoparticles

Background: α-Mangostin (αMG) is a natural substance that exerts a wide range of antitumor effects. Recently, we described that free αMG was able to dissociate multicellular tumour spheroids (MCTSs) generated from breast carcinoma cells and to reduce their cellular viability and motility. Here, αMG was encapsulated into lipidic nanoparticles (NPs), conjugated or not to a CD44 thioaptamer, and the anticancer action evaluated against MCF-7 breast MCTSs. Methods: NPs containing αMG were formulated with a core of polylactic-co-glycolyc acid. Some of them were decorated with a CD44 thioaptamer using as catalysts 1-ethyl-3- (3-dimethylaminopropyl) carbodiimide and N-hydroxysuccinimide. Both size and density of MCF-7-derived MCTSs were monitored during 72 h of treatment with NPs carrying 0.1, 0.5 and 1.0 μg/ml final concentrations of αMG. MCTSs were cultured on Matrigel or gelatine to better simulate the extracellular environment. Results: The NPs without thioaptamer and conveying 0.1 μg/ml αMG caused a significant dissociation of the MCTSs grown in gelatine after 24 h of treatment (p < 0.01). The most significant disaggregation of MCTSs was obtained using NPs carrying 0.5 μg/ml αMG (p < 0.01). A similar dissociating effect was observed when MCTSs were cultured in Matrigel under the same conditions for 48 - 72 h. By contrast, only concentrations over 1.0 μg/ml of free αMG were able to provoke a damage to MCTSs, consisting in a substantial reduction in their size (p < 0.05). Since the MCTS dissociation induced by αMG-loaded NPs occurred only in the presence of Matrigel or gelatine, an impairment of cell contacts to collagen fibres was likely responsible of this effect. Finally, the treatment of MCTSs with αMG-loaded NPs that were conjugated to the CD44 thioaptamer caused a similar decrease in density but a lower expansion of the spheroid, suggesting that a significant number of cells were died or arrested in cycle. Conclusion: Very low concentrations of αMG delivered by lipidic NPs are sufficient to provoke a substantial disaggregation of MCF-7 MCTSs that involves cell-to-collagen contacts. Similarly, the treatment of MCTSs with NPs conjugated to a CD44 thioaptamer leads to MCTS dissociation but through a more damaging action that causes also a reduction in cell number.

Differential Response of Non-cancerous and Malignant Breast Cancer Cells to Conditioned Medium of Adipose tissue-derived Stromal Cells (ASCs)

Background: The application of adipose tissue-derived stromal cells (ASCs) in regenerative medicine has become a growing trend due to its abundance and differentiation potentials. However, several breast cancer studies indicated that ASCs promote tumor progression, therefore, the use of ASCs for reconstruction after oncological surgery poses potential risks. In this study, we aimed to examine whether cancerous or non-cancerous breast cells will exhibit different responses to ASC-derived CM. Methods: ASCs were isolated from residuals of subcutaneous adipose tissue obtained from patients undergoing surgery. Cancerous MCF-7, MDA-MB231, and MDA-MB468 cell lines and one non-cancerous M10/H184B5F5 cell line were cultured with variant concentrations of ASC-derived conditioned medium (CM) for analysis. Results: ASC-derived CM significantly reduced cell viability by triggering apoptosis in MCF-7, MDA-MB231, and MDA-MB468 cell lines. ATM-Chk2-dependent DNA damage response was activated early in cancer cells when exposed to ASC-derived CM. By contrast, prompted cell proliferation instead of cell death was detected in M10/H184B5F5 cells under the treatment of lower CM concentration. Even when exposed to the highest concentration of CM, only cell cycle arrest accompanied by a weak DNA damage response were detected in M10/H184B5F5 cells, no cell deaths were observed. Conclusions: Overall, this study demonstrated that cancerous and non-cancerous breast cells respond differently to ASC-derived CM. ASC-derived CM triggered significant cell death in breast cancer cell lines, however non-cancerous breast cells exhibited dissimilar response to ASC-derived CM.

Repositioning of Anti-parasitic Drugs in Cyclodextrin Inclusion Complexes for Treatment of Triple-Negative Breast Cancer

Drug repositioning refers to the identification of new therapeutic indications for drugs already approved. Albendazole and ricobendazole have been used as anti-parasitic drugs for many years; their therapeutic action is based on the inhibition of microtubule formation. Therefore, the study of their properties as antitumor compounds and the design of an appropriate formulation for cancer therapy is an interesting issue to investigate. The selected compounds are poorly soluble in water, and consequently, they have low and erratic bioavailability. In order to improve their biopharmaceutics properties, several formulations employing cyclodextrin inclusion complexes were developed. To carefully evaluate the in vitro and in vivo antitumor activity of these drugs and their complexes, several studies were performed on a breast cancer cell line (4T1) and BALB/c mice. In vitro studies showed that albendazole presented improved antitumor activity compared with ricobendazole. Furthermore, albendazole:citrate-β-cyclodextrin complex decreased significantly 4T1 cell growth both in in vitro and in vivo experiments. Thus, new formulations for anti-parasitic drugs could help to reposition them for new therapeutic indications, offering safer and more effective treatments by using a well-known drug.

An Effect of Culture Media on Epithelial Differentiation Markers in Breast Cancer Cell Lines MCF7, MDA-MB-436 and SkBr3

Background and objectives: Cell culture is one of the mainstays in the research of breast cancer biology, although the extent to which this approach allows to preserve the original characteristics of originating tumor and implications of cell culture findings to real life situations have been widely debated in the literature. The aim of this study was to determine the role of three cell culture media on transcriptional expression of breast cancer markers in three breast cancer reference cell lines (MCF7, SkBr3 and MDA-MB-436). Materials and methods: Cell lines were conditioned in three studied media (all containing 5% fetal bovine serum (FBS) + hormones/growth factors; different composition of basal media) for four passages. Population growth was characterized by cumulative population doubling levels, average generation time, cell yield and viability at the fourth passage. Transcriptional expression of breast cancer differentiation markers and regulatory transcriptional programs was measured by qPCR. Results: Differences in the composition of growth media significantly influenced the growth of studied cell lines and the expression of mammary lineage governing transcriptional programs and luminal/basal markers. Effects of media on transcriptional expression were more pronounced in luminal cell lines (MCF7, SkBr3), than in the basal cell line (MDA-MB-436). Changes in growth media in terms of supplementation and basal medium delayed growth of cells, but improved cell yields. Conclusions: The expression of breast cancer cell differentiation phenotypic markers depends on the composition of cell growth medium, therefore cell culture as a tool in phenotypic studies should be used considering this effect. The findings of such studies should always be interpreted with caution. The formulation of cell growth media has greater effect on the expression of phenotypic markers in luminal, rather than basal cell lines. Media containing mitogens and higher vitamin content improved efficacy of cell culture in terms of cell yields, although greatly increased growth times.

Quantitative assessment of cancer cell morphology and motility using telecentric digital holographic microscopy and machine learning

The noninvasive, fast acquisition of quantitative phase maps using digital holographic microscopy (DHM) allows tracking of rapid cellular motility on transparent substrates. On two-dimensional surfaces in vitro, MDA-MB-231 cancer cells assume several morphologies related to the mode of migration and substrate stiffness, relevant to mechanisms of cancer invasiveness in vivo. The quantitative phase information from DHM may accurately classify adhesive cancer cell subpopulations with clinical relevance. To test this, cells from the invasive breast cancer MDA-MB-231 cell line were cultured on glass, tissue-culture treated polystyrene, and collagen hydrogels, and imaged with DHM followed by epifluorescence microscopy after staining F-actin and nuclei. Trends in cell phase parameters were tracked on the different substrates, during cell division, and during matrix adhesion, relating them to F-actin features. Support vector machine learning algorithms were trained and tested using parameters from holographic phase reconstructions and cell geometric features from conventional phase images, and used to distinguish between elongated and rounded cell morphologies. DHM was able to distinguish between elongated and rounded morphologies of MDA-MB-231 cells with 94% accuracy, compared to 83% accuracy using cell geometric features from conventional brightfield microscopy. This finding indicates the potential of DHM to detect and monitor cancer cell morphologies relevant to cell cycle phase status, substrate adhesion, and motility. © 2017 International Society for Advancement of Cytometry.

HSA loaded with CoFe2 O4 /MNPs as a high‐efficiency carrier for epirubicin anticancer drug delivery

Drug delivery is one of the most important challenges in the domain of health. Non‐toxic and biocompatible carriers are provided by human serum albumin nano‐capsule (HSA/NC) for drug delivery applications. In this study, HSA, with high loadings of drug‐modified cobalt ferrite (CoFe2 O4) magnetic nanoparticle (CoFe2 O4 /MNPs) was fabricated for epirubicin anticancer drug delivery. In the initial step, CoFe2 O4 /MNPs was synthesised via co‐precipitation technique and characterised by X‐ray powder diffraction, vibrating sample magnetometry, energy dispersive X‐ray analysis, scanning electron microscopy and map analysis. Furthermore, CoFe2 O4 /MNPs and epirubicin were loaded into HSA/NC and utilised as a novel system against breast cancer cell line (MCF‐7). IC50 for free epirubicin, unloaded CoFe2 O4 /MNPs/HSA/NC, CoFe2 O4 /MNPs and epirubicin‐loaded CoFe2 O4 /MNPs/HSA/NC were 7.7, 2400, 840 and 430 μg/ml, respectively. The results obtained revealed high cytotoxicity effect of epirubicin‐loaded CoFe2 O4 /MNPs on breast cancer cell line.

Stealth, biocompatible monoolein-based lyotropic liquid crystalline nanoparticles for enhanced aloe-emodin delivery to breast cancer cells: in vitro and in vivo studies

Recently, research has progressively highlighted on clues from conventional use of herbal medicines to introduce new anticancer drugs. Aloe-emodin (AE) is a herbal drug with promising anticancer activity. Nevertheless, its clinical utility is handicapped by its low solubility. For the first time, this study aims to the fabrication of surface-functionalized polyethylene glycol liquid crystalline nanoparticles (PEG-LCNPs) of AE to enhance its water solubility and enable its anticancer use. Developed AE-PEG-LCNPs were optimized via particle size and zeta potential measurements. Phase behavior, solid state characteristics, hemocompatibility, and serum stability of LCNPs were assessed. Sterile formulations were developed using various sterilization technologies. Furthermore, the potential of the formulations was investigated using cell culture, pharmacokinetics, biodistribution, and toxicity studies. AE-PEG-LCNPs showed particle size of 190 nm and zeta potential of −49.9, and PEGylation approach reduced the monoolein hemolytic tendency to 3% and increased the serum stability of the nanoparticles. Sterilization of liquid and lyophilized AE-PEG-LCNPs via autoclaving and γ-radiations, respectively, insignificantly affected the physicochemical properties of the nanoparticles. Half maximal inhibitory concentration of AE-PEG-LCNPs was 3.6-fold lower than free AE after 48 hours and their cellular uptake was threefold higher than free AE after 24-hour incubation. AE-PEG-LCNPs presented 5.4-fold increase in t_1/2 compared with free AE. Biodistribution and toxicity studies showed reduced AE-PEG-LCNP uptake by reticuloendothelial system organs and good safety profile. PEGylated LCNPs could serve as a promising nanocarrier for efficient delivery of AE to cancerous cells.

Mirabolides A and B; New Cytotoxic Glycerides from the Red Sea Sponge Theonella mirabilis

As a part of our continuing work to find out bioactive lead molecules from marine invertebrates, the CHCl₃ fraction of the organic extract of the Red Sea sponge Theonella mirabilis showed cytotoxic activity in our primary screen. Bioassay-guided purification of the active fractions of the sponge’s extract resulted in the isolation of two new glycerides, mirabolides A and B (1 and 2), together with the reported 4-methylene sterols, conicasterol (3) and swinhosterol B (4). The structures of the compounds were assigned by interpretation of their 1D (¹H, ¹³C), 2D (COSY, HSQC, HMBC, ROESY) NMR spectral data and high-resolution mass determinations. Compounds 1–4 displayed marked cytotoxic activity against human breast adenocarcinoma cell line (MCF-7) with IC₅₀ values of 16.4, 5.18, 6.23 and 3.0 μg/mL, respectively, compared to 5.4 μg/mL observed by doxorubicin as reference drug.

Assessment of cell line competence for studies of pharmacological GPR30 modulation

CONTEXT/OBJECTIVE

Cell lines used to study the role of the G protein-coupled receptor 30 (GPR30) or G protein-coupled estrogen receptor (GPER) as a mediator of estrogen responses have yielded conflicting results. This work identified a simple assay to predict cell line competence for pharmacological studies of GPR30.

MATERIALS AND METHODS

The phosphorylation or expression levels of ERK1/2, Akt, c-Fos and eNOS were evaluated to assess GPR30 activation in response to known agonists (17β-estradiol and G-1) in MCF-7 and T-47D breast cancer cell lines and in bovine aortic endothelial cells. GPR30 expression was analyzed by qRT-PCR and Western blot with two distinct antibodies directed at its carboxy and amino terminals.

RESULTS

None of the agonists, at any of the concentrations tested, activated any of those target proteins. Additional experiments excluded the disruption of the signaling pathway, interference of phenol red in the culture medium and constitutive proteasome degradation of GPR30 as possible causes for the lack of response of the three cell lines. Analysis of receptor expression showed the absence of clearly detectable GPR30 species of 44 and 50-55 kDa previously identified in cell lines that respond to 17β-estradiol and G-1.

DISCUSSION AND CONCLUSION

Cells that do not express the 44 and 50-55 kDa species do not respond to GPR30 agonists. Thus, the presence or absence of these GPR30 species is a simple and rapid manner to determine whether a given cell line is suitable for pharmacological or molecular studies of GPR30 modulation.

Effects of methylglyoxal and glyoxalase I inhibition on breast cancer cells proliferation, invasion, and apoptosis through modulation of MAPKs, MMP9, and Bcl-2

Emerging evidence indicates that methylglyoxal (MG) can inhibit tumorigenesis. Glyoxalase I (GLOI), a MG degradation enzyme, is implicated in the progression of human malignancies. However, little is known about the roles of MG and GLOI in breast cancer. Our purpose was to investigate the anticancer effects of MG and inhibition of GLOI on breast cancer cells and the underlying mechanisms of these effects. Our findings demonstrate that cell viability, migration, invasion, colony formation, and tubule formation were significantly restrained by addition of MG or inhibition of GLOI, while apoptosis was significantly increased. Furthermore, the expression of p-JNK, p-ERK, and p-p38 was markedly upregulated by addition of MG or inhibition of GLOI, whereas MMP-9 and Bcl-2 expression levels were dramatically decreased. These effects were augmented by combined treatment with MG and inhibition of GLOI. Collectively, these data indicate that MG or inhibition of GLOI induces anticancer effects in breast cancer cells and that these effects are potentiated by combination of the 2. These effects were modulated by activation of the MAPK family and downregulation of Bcl-2 and MMP-9. These findings may provide a new approach for the treatment of breast cancer.

Effect of baicalein on the expression of SATB1 in human breast cancer cells

The aim of the present study was to investigate the effects of baicalein on the protein expression of SATB1 in the MDA-MB-231 human breast cancer cell line. MDA-MB-231 cells were treated with various concentrations of baicalein (0, 10, 20, 40 µM). Following treatment, a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay and wound healing assay were used to detect the changes in cell proliferation and migration. In addition, western blot analysis was performed to detect the changes in the protein expression levels of SATB1 in the MDA-MB-231 cell line. With the prolongation of administration time and the increase in drug concentration, the inhibitory effect of baicalein on the proliferation and migration of MDA-MB-231 cells gradually increased in a time- and dose-dependent manner (P<0.05). In addition, baicalein was shown to markedly decrease the protein expression levels of SATB1 in the MDA-MB-231 cells. With increasing drug concentrations, the protein expression levels of SATB1 decreased gradually (P<0.05). Therefore, baicalein was demonstrated to inhibit the proliferation of MDA-MB-231 cells and downregulate the protein expression of SATB1, indicating that baicalein can significantly inhibit the proliferation, migration and invasiveness of MDA-MB-231 cells by downregulating the expression of SATB1.

Protein tyrosine phosphatases as novel targets in breast cancer therapy

Breast cancer is linked to hyperactivation of protein tyrosine kinases (PTKs), and recent studies have unveiled that selective tyrosine dephosphorylation by protein tyrosine phosphatases (PTPs) of specific substrates, including PTKs, may activate or inactivate oncogenic pathways in human breast cancer cell growth-related processes. Here, we review the current knowledge on the involvement of PTPs in breast cancer, as major regulators of breast cancer therapy-targeted PTKs, such as HER1/EGFR, HER2/Neu, and Src. The functional interplay between PTKs and PTK-activating or -inactivating PTPs, and its implications in novel breast cancer therapies based on targeting of specific PTPs, are discussed.

Inhibition of lymphokine-activated killer cell generation by cultured tumor cell lines in vitro

The co-culture of human peripheral blood mononuclear cells (PBMC) with high concentrations of interleukin 2 normally generates lymphokine-activated killer (LAK) cells capable of indiscriminate lysis of tumor targets. However, the addition of certain cell-line-derived tumor cells to the LAK generation cultures within the first 48 h of culture initiation resulted in the suppression of the LAK cytotoxicity measured after 3-4 days of culture. Suppression could be achieved with tumor cell:PBMC ratios as low as 1:50 when tumor cells were derived from melanoma and colorectal cancer (G361, COLO320, HT-29), but suppression was not observed with cells from the breast cancer cell line SKBr3. No suppression of LAK generation was observed with normal epithelial cells from colon or breast, with autologous or allogeneic lymphoblasts, or with allogeneic vascular endothelial cells. Suppression was independent of the removal of adherent cells from PBMC, could not be prevented by indomethacin and was not attributable to interleukin 2 absorption/adsorption by tumor cells. The suppressive activity of some tumor cells could be augmented by preculture in recombinant gamma interferon. Serum-free supernatants from G361, COLO320 and HT-29 (but not SKBr3 or endothelial cells) were also highly suppressive towards the generation of LAK cells. The elaboration by tumor cells of factors capable of inhibiting LAK generation may partially explain the failure of LAK/interleukin 2 therapy in some experimental and clinical protocols.