Negative Human Breast Cancer Cell Research Articles

PRIMA-1 synergizes olaparib-induced cell death in p53 mutant triple negative human breast cancer cell line via restoring p53 function, arresting cell cycle, and inducing apoptosis.

This study concerned with assessing the effect of restoring p53 using PRIMA-1 on the anti-cancer activity of olaparib against TP53-mutant triple negative breast cancer (TNBC) cells and exploring the optimum synergistic concentrations and the underlying mechanism. Human BC cell lines, MDA-MB-231 with mutated TP53 gene, and MCF-7 with wild-type TP53 gene were treated with olaparib and/or PRIMA-1. The IC50 value for olaparib was significantly decreased by PRIMA-1 in MDA-MB-231 cells compared to MCF-7 cells. Contrary to MCF-7 cells, co-treatment with olaparib and PRIMA-1 had a synergistic anti-proliferative effect in MDA-MB-231 at all tested concentrations with the best synergistic combination at 45and 8.5µM, respectively, and furthermore PRIMA-1 enhanced olaparib-induced apoptosis. This synergistic apoptotic effect was associated with a significant boost in mRNA expression of TP53 gene, cell cycle arrest at G2/M phase, modulation of BRCA-1, BAX and Bcl2 proteins expressions, and induction of active caspase-3. These results present a clue for the utility of combined olaparib and PRIMA-1 in treatment of TP53-mutant TNBC invitro. PRIMA-1 triggers olaparib-induced MDA-MB-231 cell death in a synergistic manner via restoring TP53, decreasing BRCA-1 expression, cell cycle arrest, and enhancement of apoptosis via p53/BAX/Bcl2/caspase 3 pathway.

Glucanoacetobacter kombuchae (RG3T), a novel bacteria for AgNPs biosynthesis: Characterization and comprehensive evaluation of bioactivity

An innovative green route has been adapted in this study to biosynthesize Silver Nanoparticles (AgNPs) for the first time using the cell exudate of a novel bacteria Gluconacetobacter kombucha (RG3 T ). Bio-reduction of silver was carried out by adding AgNO 3 and glucose along with the bacterial cell exudate. The onset of dark brown colour indicated the synthesis of nanoparticles (NPs) and was further validated by absorption spectrum at 430 nm using UV–Vis Spectroscopy. X-ray diffraction (XRD) study clearly illustrated the crystalline phase of the formed NPs. Further, morphological studies was done by Transmission electron microscope (TEM) which showed an approximate size of 20 nm exhibiting the shape of a sphere. Along with this, results obtained from Scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), and Dynamic light scattering (DLS) particle size analyzer also confirmed the surface morphology and functional group of the NPs. Broad spectrum antibacterial activity with Gram positive and negative bacteria were evaluated along with the antioxidant activity which showed high potency of NPs. RG3 T -NPs were treated against cell lines like MCF-7, HEPG-2, and notedly against Triple negative human breast cancer (TNBC) cell line which showed it’s superior efficiency. Therefore, it can be concluded that RG3 T -NPs points itself to be a significant bio-material with antibacterial, cytotoxic, and antioxidant properties. • This is the first study to report biosynthesis of AgNPs using Glucanoacetobacter kombuchae (RG3 T ). • Green synthesis has been carried out using the cell exudate of RG3 T along with glucose and AgNO 3 . • Significant bioactivity was assessed by antibacterial, cytotoxic, and antioxidant activity.

Abstract PR007: Candidate antigens for a ductal carcinoma in situ vaccine, essential for breast cancer cell survival across multiple subtypes, are immunogenic in DCIS and IBC

Abstract Vaccine therapy may to destroy the current ductal carcinoma in situ (DCIS), prevent recurrence, and have little risk of long-term complications. One of the limitations for a DCIS vaccine is identifying appropriate antigens which, when targeted, may be able to treat DCIS and prevent development of IBC. In this study, we identified proteins that were overexpressed in both DCIS and IBC tumors across fifteen human Geo and Array Express data sets. From the 68 candidate proteins, twelve proteins expression was necessary for cancer cell survival across breast cancer subtypes using a high throughput siRNA screen. We chose candidates that increased apoptosis and decreased cell survival in human HER2 positive (HER2), triple negative (TN), and hormone receptor positive HER2 negative (HR) human breast cancer cell lines with decreased expression of the target protein. Twelve proteins (AURKA, KIF11, NDC80, RRM2, SDC1, UBE2C, HJURP, CENPA, CENPF, HIST2H2AA3, KRT8, and TOP2A) were the twelve antigens developed for the vaccine. All twelve targets were immunogenic in women with DCIS and IBC as compared to age matched control women. For example, autoantibodies to four of the antigens (AURKA, NDC80, KRT8, and RRM2) predicted women with DCIS with AUC 0.69 (p=0.005 95% CI 0.56 to 0.80) and IBC with AUC 0.79 (p<0.001 95% CI 0.66 to 0.90) as compared to age matched control women in a discovery set of 59 DCIS patients, 37 IBC patients, and 43 control women. In an independent validation set of serum samples of 50 DCIS, 60 IBC, and 50 control patients, autoantibodies to the four candidate antigens could predict women with DCIS with AUC 0.62 (p=0.04, 95% CI 0.51 to 0.73) and IBC with AUC 0.69 (p<0.001, 95% CI 0.60 to 0.79). Autoantibodies to the four DCIS antigens could identify each subtype of breast cancer subtype as compared to control, HR+(n=20 patients) with AUC 0.69 (p=0.01, 95% CI 0.55 to 0.83), HER2+ (n=20 patients) with AUC 0.70 (p=0.01, 95% CI 0.55 to 0.84), and TN (n=20 patients) with AUC 0.74 (p=0.002, 95% CI 0.61 to 0.87). All these were IgG autoantibodies suggest pre-existing T cells that recognize the candidate antigens because Ig class switching from IgM to IgG requires antigen-specific T cells. These twelve candidate antigens, overexpressed in human breast cancer, are also overexpressed in the TgMMTV-neu and C3(1)Tag transgenic mouse mammary tumor models of breast cancer. Vaccination with human MHC Class II predicted epitopes from KRT8, conserved between mouse and human, inhibited tumor growth in TgMMTV-neu mice by 47% and C3(1)Tag by 62%. The KRT8- specific IFN-g immune response developed was associated with lower tumor volume with mice vaccinated with the human MHC Class II Th1 KRT8 epitopes with the KRT8-specific IFN-g immune response associated with smaller tumors in TgMMTV-neu mice (R2= 0.64, p=0.02). We plan to develop these antigens in a multi-antigen DCIS vaccine that may be able to destroy DCIS and prevent breast cancer across all breast cancer subtypes. Citation Format: Sasha E. Stanton, Jason Schlumbohm, Mary L. Disis. Candidate antigens for a ductal carcinoma in situ vaccine, essential for breast cancer cell survival across multiple subtypes, are immunogenic in DCIS and IBC [abstract]. In: Proceedings of the AACR Special Conference on Rethinking DCIS: An Opportunity for Prevention?; 2022 Sep 8-11; Philadelphia, PA. Philadelphia (PA): AACR; Can Prev Res 2022;15(12 Suppl_1): Abstract nr PR007.

Self-assembled albumin nanoparticles for redox responsive release of curcumin

The synthesis of stimuli-responsive protein-based nanocarriers often involves multi-step processing or use of toxic crosslinkers, which impede their wide-spread utilization as drug delivery systems. In this study, we report a facile, self-assembly based method for the synthesis of redox responsive albumin nanocarriers (<150 nm) without the use of crosslinkers. Curcumin (CUR) was encapsulated into these self-assembled albumin nanoparticles with 83.22% encapsulation efficiency and 8.33% loading capacity. These CUR loaded redox responsive albumin nanoparticles displayed glutathione (GSH) triggered CUR release due to the reduction of disulfide bonds in the protein structure. The release studies show that in the presence of GSH, 61% of the CUR is released, whereas in GSH-free environment only 18% of the drug is released within the first 12 h. In vitro studies performed on triple negative human breast cancer cells (MDA-MB-231) show that encapsulation of CUR provided enhanced cytotoxicity compared to free CUR. Furthermore, studies on the mitochondrial structure of these cells confirm that the drug loaded nanoparticles lead to the changes in mitochondria stress conditions by reacting with the GSH in the cells.

Jadomycin B Acts Synergistically with NSAIDs to Produce Cytotoxic Effects in Human Breast Cancer Cells in vitro

BackgroundBreast cancer is the most prevalent cancer in North American women. Jadomycin B is a novel compound that is effective in killing triple negative human breast cancer cells that have become resistant to anthracycline and taxane chemotherapies. The mechanism through which jadomycin B exerts its cytotoxic effect remains to be fully characterized. A quantitative PCR (qPCR) array of cancer drug targets identified cyclooxygenase‐2 (COX‐2) as a gene of interest in jadomycin B resistant breast cancer cells.ObjectiveTo explore the effects of COX‐2 signalling on jadomycin B cytotoxicity in MDA‐MB‐231 cells as a model of invasive triple‐negative, human breast cancer requiring more effective treatments.Methods and ResultsControl MDA‐MB‐231 (231‐CON) cells exposed to increasing concentrations of jadomycin B (0‐2.2 µM) over 7 months developed a 3‐fold resistance to jadomycin B as determined using methyl‐tetrazolium (MTT) cell viability assays. By qPCR, there was a significant increase in COX‐2 (40 fold, p &lt; 0.05) but not cyclooxygenase‐1 (COX‐1) (0.17 fold, p &lt; 0.05), mRNA expression in jadomycin resistant (231‐JB) versus 231‐CON cells. A similar increase in COX‐2 was not observed in mitoxantrone resistant MDA‐MB‐231 cells (231‐MITX). We therefore hypothesized that inhibition of COX‐2 signalling would increase the susceptibility of breast cancer cells to jadomycin B. The 231‐CON and 231‐JB cells were treated with jadomycin B with or without the COX‐2 selective inhibitor celecoxib (CXB), or COX‐1/2 inhibitors ibuprofen (IBU) or Naproxen (NAP). The SynergyFinder 2.0 web application was used to analyze the cytotoxicity (MTT assays) of these combinations and calculate synergy scores using the Bliss model. IBU and NAP were found to act synergistically with jadomycin B in both control and jadomycin resistant cells, while CXB acted additively (Table 1).ConclusionsJadomycin B acts additively or synergistically with inhibitors of COX‐2 in vitro, resulting in increased cytotoxic effect. These results justify further investigation into the COX‐2 signaling pathway as a means to elucidate the mechanism of action of jadomycin B. Additionally, our research has the potential to contribute to an improved understanding of breast cancer relevant COX‐2 signalling, facilitating the use of COX‐2 inhibitors as chemosensitizers.

Insight on pyrimido[5,4-g]indolizine and pyrimido[4,5-c]pyrrolo[1,2-a]azepine systems as promising photosensitizers on malignant cells

Searching for new small molecules as photosensitizing agents, we have developed a class of twenty-five pyrimido[5,4-g]indolizine and pyrimido[4,5-c]pyrrolo[1,2-a]azepines with a good substitution pattern defining a versatile synthetic pathway to approach the title ring system. All compounds were evaluated for their photocytotoxicity on a triple negative human breast cancer cell line (MDA-MB-231) in the dark and under UVA light (2.0 J/cm2). The most effective compounds exhibited a photoantiproliferative activity with IC50 values up to nanomolar ranges. Interestingly, these new developed compounds showed high selectivity towards cancerous cells with respect to non-cancerous ones. Moreover, four representative derivatives demonstrated to be phototoxic also against an additional human HER2 positive breast cancer cell line (HCC1954), and against the HER2 positive vesical cancer cell line (T24) harboring Hras mutation. Mechanistic studies performed in triple negative MDA-MB-231 cancer cells revealed the ability of the compounds to increase reactive oxygen species (ROS) production and to induce a thiol redox stress, thus triggering cancer cell death through apoptosis. Apoptotic cell death was also induced in highly aggressive and metastatic HER2 positive Hras mutated T24-treated bladder cancer cells. Overall, our data confirm that these new small photosensitizing agents may represent very promising candidates for phototherapy application against highly aggressive and resistant cancers.

Mixed Ni(II) and Co(II) complexes of nalidixic acid drug: Synthesis, characterization, DNA/BSA binding profile and in vitro cytotoxic evaluation against MDA-MB-231 and HepG2 cancer cell lines

In this work, herein we report the synthesis, structural characterization and in vitro cytotoxic evaluation of two mixed Co(II)/Ni(II)-nalidixic acid-bipyridyl complexes (1 and 2). The structural analysis of metal complexes 1 and 2 was carried out by analytical and multispectroscopic techniques (FT-IR, UV-vis, EPR, sXRD). The crystallographic details of complexes 1 and 2 revealed a monoclinic crystal system with P21/c space group. DFT studies of complexes were performed to get electronic structure and localization of HOMO and LUMO electron densities. Hirshfeld surface analysis of metal complexes 1 and 2 was employed to understand the various intermolecular interactions (C–H···O, N-H···H and O–H···O) that define the stability of crystal lattice structures. The comparative interaction studies of complex 1 and complex 2 with DNA/BSA were performed by diverse multispectroscopic and analytical techniques to evaluate their chemotherapeutic potential. The magnitude of the DNA binding propensity and binding mode was verified by calculating Kb, K and Ksv values. Higher binding affinity was observed in case of complex 2via intercalative mode. Furthermore, the cytotoxic assessment of complexes 1 and 2 was examined against MDA-MB-231 (triple negative human breast cancer cell line) and HepG2 (liver carcinoma cell line) employing MTT assay which revealed remarkably effecient and specific cytotoxic activity of complex 2.

Aza-Crown-Based Macrocyclic Probe Design for "PET-off" Multi-Cu2+ Responsive and "CHEF-on" Multi-Zn2+ Sensor: Application in Biological Cell Imaging and Theoretical Studies.

The work represents a rare example of an aza-crown-based macrocyclic chemosensor, H2DTC (H2DTC = 1,16-dihydroxy-tetraaza-30-crown-8) for the selective detection of both Zn2+ and Cu2+ in HEPES buffer medium (pH 7.4). H2DTC exhibits a fluorescence response for both Zn2+ and Cu2+ ions. The reversibility of the chemosensor in its binding with Zn2+ and Cu2+ ions is also examined using a Na2EDTA solution. H2DTC exhibits a chelation-enhanced fluorescence (CHEF) effect in the presence of Zn2+ ions and a quenching effect (CHEQ) in the presence of paramagnetic Cu2+ ions. Furthermore, the geometry and spectral properties of H2DTC and the chemosensor bound to Zn2+ have been studied by DFT and TDDFT calculations. The limit of detection (LOD) values are 0.11 × 10-9 and 0.27 × 10-9 M for Cu2+ and Zn2+, respectively. The formation constants for the Zn2+ and Cu2+ complexes have been measured by pH-potentiometry in 0.15 M NaCl in 70:30 (v:v) water:ethanol at 298.1 K. UV-vis absorption and fluorometric spectral data and pH-potentiometric titrations indicate 1:1 and 2:1 metal:chemosensor species. In the solid state H2DTC is able to accommodate up to four metal ions, as proved by the crystal structures of the complexes [Zn4(DTC)(OH)2(NO3)4] (1) and {[Cu4(DTC)(OCH3)2(NO3)4]·H2O}n (2). H2DTC can be used as a potential chemosensor for monitoring Zn2+ and Cu2+ ions in biological and environmental media with outstanding accuracy and precision. The propensity of H2DTC to detect intracellular Cu2+ and Zn2+ ions in the triple negative human breast cancer cell line MDA-MB-468 and in HeLa cells has been determined by fluorescence cell imaging.

Synthesis and characterization of a tetra-(benzylammonium) dihydrogen decavanadate dihydrate compound inhibiting MDA-MB-231 human breast cancer cells proliferation and migration

Single crystals of tetra-(benzylammonium) dihydrogen decavanadate dihydrate, (C7H10N)4[H2V10O28]·2H2O, were grown in an aqueous solution at room temperature. The decavanadate compound was characterized by IR spectroscopy and X-ray powder diffraction. This compound crystallizes in the triclinic system, space group P-1, with a = 10.119(5) Å, b = 10.284(3) Å, c = 13.945(6) Å, α = 69.87(3), β= 72.47(4), γ = 61.15(3), V = 1177.24(1) Å3 and Z = 1. The formula unit of decavanadate compound consists of one dihydrogen decavanadate anion [H2V10O28]4−, four organic cations (C7H10N)+ and two water molecules. The three-dimensional Hirshfeld surface (3D-HS) and their relative two-dimensional fingerprint plots (2D-FP) of (C7H10N)4[H2V10O28]·2H2O compound, revealed that the structure is dominated by H…O/O…H (52.5%) and H…H (22%) contacts. Interestingly, when tested on MDA-MB231 triple negative human breast cancer cells, the (C7H10N)4[H2V10O28]·2H2O compound inhibits their proliferation and migration at a micromolar range, suggesting its potential use as therapeutic molecule against breast cancer.

Novel luminescent benzopyranothiophene- and BODIPY-derived aroylhydrazonic ligands and their dicopper(II) complexes: syntheses, antiproliferative activity and cellular uptake studies.

Two novel unsymmetrical binucleating aroylhydrazonic ligands and four dicopper(II) complexes carrying fluorescent benzopyranothiophene (BPT) or boron dipyrromethene (BODIPY) entities were synthesized and fully characterized. Complex 1, derived from the BPT-containing ligand H3L1, had its crystal structure elucidated through X-ray diffraction measurements. The absorption and fluorescence profiles of all the compounds obtained were discussed. Additionally, the stability of the ligands and complexes was monitored by UV-vis spectroscopy in DMSO and biologically relevant media. All the compounds showed moderate to high cytotoxicity towards the triple negative human breast cancer cell line MDA-MB-231. BPT derivatives were the most cytotoxic, specially H3L1, reaching an IC50 value up to the nanomolar range. Finally, fluorescence microscopy imaging studies employing mitochondria- and nucleus-staining dyes showed that the BODIPY-carrying ligand H3L2 was highly cell permeant and suggested that the compound preferentially accumulates in the mitochondria.

A study of possible toxicological effects of Methylparaben on estrogen receptor-α negative MCF-7 human breast cancer cell line

A study of possible toxicological effects of Methylparaben on estrogen receptor-α negative MCF-7 human breast cancer cell line

The palladacycle, BTC2, exhibits anti-breast cancer and breast cancer stem cell activity

In women globally, breast cancer is responsible for most cancer-related deaths and thus, new effective therapeutic strategies are required to treat this malignancy. Platinum-based compounds like cisplatin are widely used to treat breast cancer, however, they come with limitations such as poor solubility, adverse effects, and drug resistance. To overcome these limitations, complexes containing other platinum group metals such as palladium have been studied and some have already entered clinical trials. Here we investigated the anti-cancer activity of a palladium complex, BTC2, in MCF-7 oestrogen receptor positive (ER+) and MDA-MB-231 triple negative (TN) human breast cancer cells as well as in a human breast cancer xenograft chick embryo model. BTC2 exhibited an average IC50 value of 0.54 μM, a desirable selectivity index of >2, inhibited the migration of ER+ and TN breast cancer cells, and displayed anti-cancer stem cell activity. We demonstrate that BTC2 induced DNA double strand breaks (increased levels of γ-H2AX) and activated the p-ATM/p-CHK2 and p-p38/MAPK pathways resulting in S- and G2/M-phase cell cycle arrests. Importantly, BTC2 sensitised breast cancer cells by triggering the intrinsic (cleaved caspase 9) and extrinsic (cleaved caspase 8) apoptotic as well as necroptotic (p-RIP3 and p-MLKL) cell death pathways and inhibiting autophagy and its pro-survival role. Furthermore, in the xenograft in vivo model, BTC2 displayed limited toxicity and arrested the tumour growth of breast cancer cells over a 9-day period in a manner comparable to that of the positive control drug, paclitaxel. BTC2 thus displayed promising anti-breast cancer activity.

Innovative Betulin Nanosuspension exhibits enhanced anticancer activity in a Triple Negative Breast Cancer Cell line and Zebrafish angiogenesis model

We present a nanosuspension of betulin, a BCS class II anticancer drug, particularly effective against resistant breast cancer. As anticancer efficacy of betulin is hampered by poor aqueous solubility, a nanosuspension with surface area was considered to enhance efficacy. An innovative approach wherein the betulin nanosuspension is generated instantaneously in situ, by adding a betulin preconcentrate (BeTPC) comprising drug and excipients, to aqueous medium, is successfully demonstrated. The optimal BeTPC when added to isotonic dextrose solution instantaneously generated an in situ nanosuspension (BeTNS-15) with high precipitation efficiency (92.7 ± 1.21%), average particle size (383.74 ± 7.24 nm) and good stability as per ICH guidelines. TEM revealed elongated particles while DSC and XRD indicated partial amorphization. Significantly higher cytotoxicity of BeTNS-15 (IC50 38.44 µg/ml) compared to betulin (BetS) (IC50 69.54 µg/ml) in the resistant triple negative human breast cancer cell line MDA-MB-231, was attributed to high intracellular uptake confirmed by HPLC and Imaging Flow cytometry (IFC). IFC confirmed superior anti-cancer efficacy of BeTNS-15 mediated by mitochondrial membrane disruption and inhibition of the G0/G1 phase. BeTNS-15 also exhibited significantly greater anti-angiogenic efficacy (p < 0.05) in the zebrafish model confirming superior efficacy. Simplicity of the innovative in situ approach coupled with superior efficacy proposes BeTNS as an innovative and highly promising anticancer formulation.

PD-L1 siRNA Theranostics With a Dextran Nanoparticle Highlights the Importance of Nanoparticle Delivery for Effective Tumor PD-L1 Downregulation.

PurposeThe inhibition of immune checkpoints such as programmed cell death ligand-1 (PD-L1/CD274) with antibodies is providing novel opportunities to expose cancer cells to the immune system. Antibody based checkpoint blockade can, however, result in serious autoimmune complications because normal tissues also express immune checkpoints. As sequence-specific gene-silencing agents, the availability of siRNA has significantly expanded the specificity and range of “druggable” targets making them promising agents for precision medicine in cancer. Here, we have demonstrated the ability of a novel biodegradable dextran based theranostic nanoparticle (NP) to deliver siRNA downregulating PD-L1 in tumors. Optical imaging highlighted the importance of NP delivery and accumulation in tumors to achieve effective downregulation with siRNA NPs, and demonstrated low delivery and accumulation in several PD-L1 expressing normal tissues.MethodsThe dextran scaffold was functionalized with small molecules containing amine groups through acetal bonds. The NP was decorated with a Cy5.5 NIR probe allowing visualization of NP delivery, accumulation, and biodistribution. MDA-MB-231 triple negative human breast cancer cells were inoculated orthotopically or subcutaneously to achieve differences in vascular delivery in the tumors. Molecular characterization of PD-L1 mRNA and protein expression in cancer cells and tumors was performed with qRT-PCR and immunoblot analysis.ResultsThe PD-L1 siRNA dextran NPs effectively downregulated PD-L1 in MDA-MB-231 cells. We identified a significant correlation between NP delivery and accumulation, and the extent of PD-L1 downregulation, with in vivo imaging. The size of the NP of ~ 20 nm allowed delivery through leaky tumor vasculature but not through the vasculature of high PD-L1 expressing normal tissue such as the spleen and lungs.ConclusionsHere we have demonstrated, for the first time, the feasibility of downregulating PD-L1 in tumors using siRNA delivered with a biodegradable dextran polymer that was decorated with an imaging reporter. Our data demonstrate the importance of tumor NP delivery and accumulation in achieving effective downregulation, highlighting the importance of imaging in siRNA NP delivery. Effective delivery of these siRNA carrying NPs in the tumor but not in normal tissues may mitigate some of the side-effects of immune checkpoint inhibitors by sparing PD-L1 inhibition in these tissues.

Nanoliposomes as Multidrug Carrier of Gemcitabine/Paclitaxel for the Effective Treatment of Metastatic Breast Cancer Disease: A Comparison with Gemzar and Taxol

AbstractSeveral liposomal drugs have received clinical approval for the treatment of cancer due to the reduced side effects and/or improved therapeutic efficacy in comparison to their respective free drug counterparts. In this study, nanoliposomes are designed as multidrug carriers for codelivering gemcitabine hydrochloride (Gemzar) and paclitaxel (Taxol) and evaluating their anticancer activity in several triple negative human breast cancer cell lines and in a mouse model of metastatic breast cancer. The results demonstrate that the nanoliposomes significantly decrease the cell viability of breast cancer cells compared to combination treatment with the free drugs. Furthermore, the chemotherapeutics coloaded nanoliposomes dramatically decrease the tumor growth and improve survival times, while combination treatment with Gemzar and Taxol has a modest effect on cancer progression. Moreover, pharmacokinetic analysis demonstrates that nanoliposomes increase the half‐life of gemcitabine hydrochloride and paclitaxel 6.3‐fold and 1.7‐fold, respectively. Taken together, the findings indicate that gemcitabine hydrochloride and paclitaxel‐coloaded nanoliposomes can provide an effective treatment strategy for metastatic breast cancer.

11‐Keto‐a‐Boswellic Acid, a Novel Triterpenoid from Boswellia spp., with Cytotoxic Efficacy against Treatment‐Resistant Triple Negative Breast Cancer Cell Lines

Triterpenoids including biologically active boswellic acids constitute about twenty percent of frankincense, the oleogum resin of Boswellia spp. trees from the Burseraceae family [1– 2]. Frankincense as well as extracts thereof have been traditionally used by folk medicines, such as Ayurveda, African, Arab, and Chinese medicine, for the treatment of fever and pain. Several clinical pilot trials provided evidence for a potential therapeutic efficacy of frankincense preparations in various chronic inflammatory diseases. Moreover, preclinical studies have demonstrated that boswellic acids may be beneficial for treatment of human cancers because they also inhibit tumor growth in different animal models. We have performed a comparative analysis of more than 40 oleogum resins from different Boswellia species grown in different geographic locations [1] and we have shown that frankincense extracts induce apoptosis in triple negative breast cancer cell lines in vitro and in vivo [1– 2]. Moreover, the cytotoxic efficacy of the extracts correlated positively with the contents of boswellic acids [2]. Boswellic acids exist as two structural isomers, α‐boswellic acids (oleanane‐type skeleton) and β‐boswellic acids (ursane‐type skeleton). In the current study, we have identified the novel oleanane‐type 11‐keto‐α‐boswellic acid (αKBA) in oleogum resins of different Boswellia species. The structure of αKBA was elucidated by 1D and 2D 1H and 13C NMR analysis. The contents of the individual boswellic acid isomers was quantified in different frankincense extracts by high performance reversed‐phase liquid chromatography coupled with tandem mass spectrometric detection (HPLC‐MS/MS) and the help of fluorinated stationary phases. We have compared the toxicities of different known boswellic acids and of the newly identified αKBA against tthe reatment‐resistant, triple negative human breast cancer cell lines MDA‐MB‐231 and CAL‐148. αKBA exhibited cytotoxic activity against the cancer cells and was less toxic to normal peripheral blood mononuclear cells (PBMC) and non‐malignant human breast epithelial cells indicating tumor selectivity. Structure‐activity‐relationship between the cytotoxic activities of different boswellic acid were analyzed. Hence, the study provides evidence for the existence of a novel biologically active boswellic acid with cytotoxic activity against triple negative human breast cancer cell lines in the oleogum resin of Boswellia spp. Additionally, it offers new clues for possible structural modifications of boswellic acids to increase their cytotoxicity against cancer cells.Support or Funding InformationThis work was supported by the Academic Center for Complementary and Integrative Medicine (AZKIM), State Ministry of Baden‐Württemberg for Sciences, Research and Arts.

Curcumin‐Induced Apoptosis Pathways in Positive and Negative Human Epidermal Growth Factor Receptor Breast Cancer Cells

AimCurcumin, have several advantages and potential health benefits, such as low cytotoxicity and minimal development of resistance, as compared to chemically‐based therapies, and have anti‐cancerous efficacies, including induction of apoptosis, in cancer cells of various tissue origins. The aim of this study was toelucidate the mechanisms of curcumin‐induced apoptosis in human epidermal growth factor receptor positive (BT474) and negative (MCF‐7) breast cancer cell lines.MethodsCytotoxic activity of curcumin was measured by the sulphorhodamine B assay. We studied the induction of apoptosis by flow cytometry and detection of an apoptosis‐associated PARP cleavage product via Western blotting. Westernblotting was also used to measure Cytochrome C translocation, which determines mitochondrial involvement and caspase‐7 activation. The Caspase cascade was measured by activity levels of caspase‐3, caspase‐8, and caspase‐9 using chromogenic substrates.ResultsCurcumin CC50 (concentration that kills 50% of the cells) was 25.92 ±5.13μM for MCF‐7, and 49.96 ± 5.98 μM for BT474 cells. Flow cytometry results indicated a 13.36 ±5.96% expression increase and a 6.87 ± 1.42% expression increase in early stage apoptosis (Annexin V positively stained cells) in MCF‐7 and BT474 cells, respectively. Late stage apoptosis (dual stained Annexin V/Propidium Iodide (PI)cells) in curcumin exposed MCF‐7 cells was increased by 3.45 ± 0.94% expression, but no increase was seen in BT474 cells. PARP cleavage product (89kD) was detected at similar levels in both curcumin exposed MCF‐7 and BT474 cells and in a dose dependent manner. Curcumin‐exposedMCF‐7 cells, but not BT474 cells, showed substantial release of Cytochrome C from the mitochondria into the cytoplasm. Curcumin significantly upregulatedcaspase‐8 activity without modulating the activity of caspase‐9 in both BT474 and MCF‐7 cells. However, Caspase‐3 activity was upregulated only in BT474 cells. MCF‐7 cells reportedly have a gene deletion for Caspase‐3 and therefore do not express it. Caspase‐7 was then tested in MCF‐7 cells, but no upregulation was measured.ConclusionCytotoxicity of Curcumin is low for both MCF‐7 and BT474 cells and concentrations are easily achievable. Apoptosis induction by Curcumin exposure was detected by both PARP cleavage and flow cytometry. Flow cytometry showed that curcumin induced predominantly early stage apoptosis (Annexin V stained) in both BT474 and MCF‐7 cells, with a late‐stage apoptosis increase seen only in MCF‐7. Caspase studies determined an extrinsic pathway (Caspase‐8 and Caspase‐3 positive, Caspase‐9 negative) in BT474 cells. MCF‐7 cells were also Caspase‐8 positive, Caspase‐9 negative, but Caspase‐3 was not detected. In the absence of Caspase‐3, Caspase‐7 might serve as an effector caspase. However, Curcumin exposure did not upregulate its expression in MCF‐7 cells. While curcumin activated the mitochondria‐independent extrinsic pathway in BT474 cells (no translocation of Cytochrome C into the cytoplasm), a mitochondria‐dependent (translocation of Cytochrome C into the cytoplasm), extrinsic with possible intrinsic pathway involvement was activated in MCF‐7 cells. Further studies are needed to elucidate the altered apoptotic pathway utilized in MCF‐7 cells.

Development and Characterization of Solid Dispersion System for Enhancing the Solubility and Dissolution Rate of Dietary Capsaicin

Background:Capsaicin is a pungent component of chili peppers that suppresses the growth of various cancer cell lines including breast cancer. However, it shows extremely low oral bioavailability due to its poor water solubility.Objective:The objective of the present work was to improve the solubility and dissolution rate of capsaicin.Methods:Solid dispersions were prepared by the solvent evaporation method using different molar ratios of capsaicin and urea (1:1, 1:2, and 1:3). Differential Scanning Calorimetry (DSC) and X-Ray Diffraction (XRD) study were used to characterize the solid dispersion. Solid dispersions were evaluated for solubility, dissolution rate and in vitro cytotoxicity in breast cancer cell lines.Results:XRD and DSC studies exhibited the reduced crystallinity of a drug in solid dispersion. Phase solubility study shows that the drug solubility increased by increasing carrier concentration. In vitro release study of the solid dispersion showed the faster dissolution of a drug with increasing carrier concentration. Solid dispersion formulation effectively inhibited the growth of MCF-7 human breast cancer and MDA-MB-231 triple negative human breast cancer cells in an MTT assay that measures metabolic activity, but only slightly decreased cell viability when compared to capsaicin alone.Conclusion:The present study demonstrated that solid dispersion of capsaicin in PEG 6000 overcomes the problems related to the poor aqueous solubility of this drug and improving its dissolution rate.

Anticancer Efficacy of Thevetia peruviana (Pers.) K. Schum. Extracts on Triple Negative Human Breast Cancer Cell Line

In this 21st century cancer has become the second big reason for death next to heart attack in both developed and the developing countries. Worldwide, there are almost 2.1 million newly diagnosed breast cancer cases in 2018, accounting for 1 in 4 cancer cases among women. Triple Negative Human Breast Cancer is one of the types of human breast cancer. The plant extracts of Thevetia peruviana (Pers.) K. Schum. has been used against the Triple Negative Human Breast Cancer cell line MDA-MB-231 for the current experiment All the 5 parts (leaf, stem, flower, fruit and seed) had been selected for the experiment and the extracts of the various parts were made in hydro-alcoholic solvent i.e. methanol: Water.

A domino annulation approach to 3,4-diacylpyrrolo[1,2-a]pyrazines: decoration of pyrazine units.

A new one-pot, sequential three-component access to 3,4-diacylpyrrolo[1,2-a]pyrazine was achieved from the reaction of an α-haloketone, azide, and N-substituted pyrrole-2-carboxaldehyde under mild reaction conditions, through which a polysubstitution pattern on the pyrazine moiety of the scaffold was realized. The formation of multiple bonds (one C-C and two C-N) was enabled by this domino process involving the in situ generation of α-iminoketones, intermolecular Mannich reaction, intramolecular imine formation, and aromatization. Construction of the relevant 3,4-diacylpyrazino[1,2-a]indole and further expansion of this chemical space via synthetic elaboration of the resulting products were demonstrated as well. Preliminary biological screening of the synthesized derivatives against oral adenosquamous carcinoma cells (CAL-27) and triple negative human breast cancer cells (MDA-MB-231) led us to identify a potent hit compound (7o) having ∼3 times stronger in vitro anticancer activity than that of the anticancer agent, capecitabine.