Incorporation of exemestane into ternary nanosponge system for enhanced anti-tumor potential in breast cancer.

The present investigation reports the potential of exemestane loaded cyclodextrin based nanosponges for the treatment of breast cancer. Fourier transform infrared, and nuclear magnetic resonance (NMR) spectroscopic analysis confirmed the encapsulation of ring B, C, and D of exemestane in the nanosponge cavity. In vitro studies demonstrated a 6.58-folds increase in the aqueous solubility and a 1.76-folds increase in the dissolution of exemestane in the optimized nanosponge formulation EF2. It also exhibited enhanced cytotoxicity in MCF-7 cell line. Pharmacokinetic studies revealed a 1.37-fold increase in Cmax and a 2.10-fold increase in oral bioavailability of EF2, as compared to its marketed product Aromasin®. Concomitantly, this nano-formulation reduced the tumor burden to 45.71% in a DMBA-induced breast cancer rat model. This EF2-treatment also improved the hematological parameters of the animals. Histopathology of breast tissue also presented reduction in characteristic cytoarchitectural features of breast tumor. In vivo toxicity studies demonstrated reduced hepatotoxicity of the nanosponge formulation when compared with Aromasin®. These results were further supported by histological studies of excised liver tissues, where the size of hepatocytes in EF2-treated animals was like the normal hepatocyte size. In conclusion, the encapsulation of exemestane in ß-cyclodextrin nanosponge along-with HPMC E5 improved its aqueous solubility, bioavailability, and ultimately therapeutic efficacy for the treatment of breast cancer.

Polymer-lipid hybrid nanoparticles of exemestane for improved oral bioavailability and anti-tumor efficacy: An extensive preclinical investigation.

Exemestane (EXE), an irreversible aromatase inhibitor, is primarily used as a first-line therapy for estrogen receptor-positive breast cancer patients. However, complex physicochemical characteristics of EXE limit its oral bioavailability (<10%) and anti-breast cancer efficacy. The present study aimed to develop a novel nanocarrier system to improve the oral bioavailability and anti-breast cancer efficacy of EXE. In this perspective, EXE-loaded TPGS-based polymer lipid hybrid nanoparticles (EXE-TPGS-PLHNPs) were prepared by the nanoprecipitation method and evaluated for their potential in improving oral bioavailability, safety, and therapeutic efficacy in the animal model. EXE-TPGS-PLHNPs showed significantly higher intestinal permeation in comparison to EXE-PLHNPs (without TPGS) and free EXE. After oral administration, EXE-TPGS-PLHNPs and EXE-PLHNPs revealed 3.58 and 4.69 times higher oral bioavailability in Wistar rats compared to the conventional EXE suspension. The results of the acute toxicity experiment suggested that the developed nanocarrier was safe for oral administration. Furthermore, EXE-TPGS-PLHNPs and EXE-PLHNPs represented much better anti-breast cancer activity in Balb/c mice bearing MCF-7 tumor xenograft with tumor inhibition rate of 72.72% and 61.94% respectively in comparison with the conventional EXE suspension (30.79%) after 21 days of oral chemotherapy. In addition, insignificant changes in the histopathological examination of vital organs and hematological analysis further confirm the safety of the developed PLHNPs. Therefore, the findings of the present investigation advocated that the encapsulation of EXE in PLHNPs can be a promising approach for oral chemotherapy of breast cancer.

Estimating individual treatment effects on COPD exacerbations by causal machine learning on randomised controlled trials.

RATIONALE: Estimating the causal effect of an intervention at individual level, also called individual treatment effect (ITE), may help in identifying response prior to the intervention. OBJECTIVES: We aimed to develop machine learning (ML) models which estimate ITE of an intervention using data from randomised controlled trials and illustrate this approach with prediction of ITE on annual chronic obstructive pulmonary disease (COPD) exacerbation rates. METHODS: We used data from 8151 patients with COPD of the Study to Understand Mortality and MorbidITy in COPD (SUMMIT) trial (NCT01313676) to address the ITE of fluticasone furoate/vilanterol (FF/VI) versus control (placebo) on exacerbation rate and developed a novel metric, Q-score, for assessing the power of causal inference models. We then validated the methodology on 5990 subjects from the InforMing the PAthway of COPD Treatment (IMPACT) trial (NCT02164513) to estimate the ITE of FF/umeclidinium/VI (FF/UMEC/VI) versus UMEC/VI on exacerbation rate. We used Causal Forest as causal inference model. RESULTS: In SUMMIT, Causal Forest was optimised on the training set (n=5705) and tested on 2446 subjects (Q-score 0.61). In IMPACT, Causal Forest was optimised on 4193 subjects in the training set and tested on 1797 individuals (Q-score 0.21). In both trials, the quantiles of patients with the strongest ITE consistently demonstrated the largest reductions in observed exacerbations rates (0.54 and 0.53, p<0.001). Poor lung function and blood eosinophils, respectively, were the strongest predictors of ITE. CONCLUSIONS: This study shows that ML models for causal inference can be used to identify individual response to different COPD treatments and highlight treatment traits. Such models could become clinically useful tools for individual treatment decisions in COPD.

Murine toxicology and pharmacokinetics of lead next generation galeterone analog, VNPP433-3ß.

VNPP433-3ß (compound 2, (3ß-(1H-imidazole-1-yl)-17-(1H-benzimidazole-1-yl)-androsta-5,16-diene), a multitarget anticancer agent has emerged as our lead next generation galeterone analogs (NGGA). Compound 2 is currently in development as potential new therapeutic for prostate and pancreatic cancers. The preliminary toxicity study reveals that the compound 2 was better tolerated by the normal male CD-1 mice than the male Nude mice. The maximum tolerated dose (MTD) in the Nude mice was estimated to be between 25 < 50 mg/kg. After oral dosing of compound 2 to male and female rats, the plasma concentration versus time curves were very consistent between animals and the AUClast increased with dose. Many plasmas concentration versus time curves profiles were nearly flat over 24 hr., suggesting extended absorption from the GI tract. Consequently, reliable values for half-life and AUCinf were not determined. Calculated oral bioavailability (using oral AUClast and excluding the outlier IV animal) ranged from 32 to 47 %. This should be considered a minimum value since the contribution to true AUC beyond 24 hr. is clearly not zero. Clearly, these toxicology and pharmacokinetics parameters pave the way for understanding the anticancer pharmacological actions and provide a meaningful basis for further preclinical development and eventual clinical development.

QbD-assisted development of lipidic nanocapsules for antiestrogenic activity of exemestane in breast cancer.

Some breast cancers are caused by hormonal imbalances, such as estrogen and progesterone. These hormones play a function in directing the growth of cancer cells. The hormone receptors in hormone receptor-positive breast cancer lead breast cells to proliferate out of control. Cancer therapy such as hormonal, targeted, radiation is still unsatisfactory because of these challenges namely multiple drug resistance (MDR), off-targeting, severe adverse effects. A novel aromatase inhibitor exemestane (Exe) exhibits promising therapy in breast cancer. This study aims to develop and optimize Exe-loaded lipid nanocapsules (LNCs) by using DSPC, PF68 and olive oil as lipid, surfactant and oil phase, respectively and to characterize the same. The prepared nanocapsules were investigated via in vitro cell culture and in vivo animal models. The LNCs exhibited cytotoxicity in MCF-7 cell lines and enhanced anti-cancer activity and reduced cardiotoxicity in DMBA-induced animal model when compared to the drug. Additionally, in vivo pharmacokinetics revealed a 4.2-fold increased oral bioavailability when compared with Exe suspension. This study demonstrated that oral administration of Exe-loaded LNCs holds promise for the antiestrogenic activity of exemestane in breast cancer.

Fluticasone propionate suppresses the SARS-CoV-2 induced increase in respiratory epithelial permeability in vitro.

BACKGROUND: Disruption of the nasal epithelial barrier is believed to play a role in Coronavirus Disease-2019 (COVID-19) outcomes. Fluticasone propionate has been shown to restore the nasal epithelial barrier in allergic rhinitis to the level of healthy controls. The therapeutic potential of nasal steroid sprays in COVID-19 has recently been reported. However, further insight into the mode of action is warranted. OBJECTIVES: To explore the in vitro mechanisms of the preventive potential of fluticasone propionate in SARS-CoV-2 infection. METHODS: Human air liquid interface cultures of Calu-3 cells and primary nasal epithelial cells isolated from healthy donors were used to investigate the preventive effect of fluticasone propionate on SARS-CoV-2 induced barrier disruption, virus replication and ACE2 expression. RESULTS: 48 hours pre-treatment with fluticasone propionate prevented the SARS-CoV-2 induced increase in fluorescein isothiocyanate-dextran 4 kDa permeability and reduced infection with SARS-CoV-2. Pre-treatment with fluticasone propionate also decreased ACE2 expression in SARS-CoV-2 infected Calu-3 cells. CONCLUSION: Fluticasone propionate pre-treatment prevented SARS-CoV-2 increased epithelial permeability, reduced ACE2 expression and SARS-CoV-2 infection, underscoring the therapeutic potential of fluticasone propionate in the context of COVID-19.

Comparative clinical pharmacology of mometasone furoate, fluticasone propionate and fluticasone furoate.

AIMS: To investigate the pharmacokinetics and effects on the hypothalamic-pituitary-adrenal (HPA) axis of mometasone furoate (MF), fluticasone propionate (FP) and fluticasone furoate (FF). METHODS: Study 1: Fourteen healthy participants received inhaled and intravenous MF (inhaled dose via Twisthaler) and FP (inhaled dose via Diskus), both given at 400 µg, using a randomised, single-dose, four-way crossover design. Study 2: Twenty-seven participants with mild to moderate asthma, who discontinued their corticosteroid medication for 5 days to obtain a baseline 24 h serum cortisol, received inhaled MF Twisthaler and FP Diskus, both given at 400 µg twice daily (BID), using a randomised, 14-day repeat dose, two-way crossover design. Study 3: Forty-four healthy participants were randomised to a double-blind, placebo-controlled, five-period crossover study where the following treatments were administered via the inhaled route for 7 days: FP Diskus (250, 500, 1000 µg BID), FF Diskus (100, 200, 400, 800, 1600 µg once daily [QD]) or placebo Diskus. In each study, 24-h serial blood samples were collected and assayed to assess concentrations of MF, 6ß-hydroxy mometasone, mometasone, FP, FF and cortisol. Pharmacokinetic and serum cortisol parameters were estimated as geometric means and 95% confidence intervals (CI). RESULTS: Study 1: For intravenous MF and FP, respectively: absolute bioavailability was 11.4% (95% CI: 7.5, 17.6) and 7.8% (6.3, 9.6); plasma clearance was 47 L/h (41, 52) and 60 L/h (52, 69); half-life was 7.4 h (6.9, 8.0) and 7.2 h (6.5, 8.0); and volume of distribution was 499 L (439, 567) and 623 L (557, 698). Inhalation of single dose MF or FP did not significantly affect serum cortisol (<10% reduction from baseline), whereas intravenous administration of MF or FP each changed serum cortisol by approximately -50% from baseline. Study 2: For MF and FP, respectively: area under the curve up to the last measurable concentration on Day 1 was 421 pg h/mL (270, 659) and 248 pg h/mL (154, 400), and on Day 14 was 1092 pg h/mL (939, 1269) and 591 pg h/mL (501, 696); absolute bioavailability was 12.8% (11.2, 14.2) and 8.9% (7.7, 10.2). On Day 14, 24-h serum cortisol change from baseline was -35% (-44%, -26%) and -18% (-28%, -5%) for MF and FP, respectively; the reduction was significantly greater for MF than FP (ratio for geometric adjusted mean serum cortisol concentration: 1.28 [1.04, 1.56]). Low plasma concentrations of 6ß-hydroxy mometasone were detected after intravenous dosing (Study 1) and after multiple inhaled dosing (Study 2); mometasone was not detected in any samples. Study 3: Inhaled FP and FF had similar systemic bioavailability estimates (12.0% [11.0, 13.2] and 15.0% [12.0, 17.3], respectively), but a differential effect on the HPA axis which was in agreement with the known 1.7-fold higher glucocorticoid receptor-binding affinity of FF versus FP. However, for FP 250 µg BID and FF 100, 200 and 400 µg QD, reduction in serum cortisol was not significantly different from placebo. For higher doses, FP 500 and 1000 µg BID, and FF 800 and 1600 µg QD, changes in serum cortisol concentration relative to placebo were -30%, -70%, -41% and -90%, respectively. Repeat inhaled dosing of FP 1000 µg/day (within the therapeutic dose range) resulted in comparable cortisol suppression to MF in the therapeutic range (30% reduction); whereas for FF this occurred at more than 3-fold above the therapeutic dose range (644 µg/day). CONCLUSIONS: Single inhaled and intravenous doses of MF and FP (400 µg) resulted in similar bioavailability and reductions in serum cortisol. Repeat dosing of inhaled MF and FP in the therapeutic range (800 µg/day) resulted in greater systemic exposure for MF, and a 35% reduction in serum cortisol that was 2-fold greater than for FP. The higher glucocorticoid receptor-binding affinity and bioavailability, lower clearance and the presence of active metabolites may contribute to the greater systemic exposure and effect on cortisol for MF. Repeat dosing of inhaled FP and FF resulted in similar systemic bioavailability but differed in terms of the dose required for comparable cortisol suppression to MF in the therapeutic range. Unlike FP and FF, MF has active metabolites that may contribute to its systemic effects, while device/formulation performance differences also exist between MF-containing products.

Efficacy of salmeterol and magnesium isoglycyrrhizinate combination treatment in rats with chronic obstructive pulmonary disease.

The most classic treatment recommended in the current chronic obstructive pulmonary disease (COPD) guidelines is glucocorticoid and ß2 receptor agonist combination, such as salmeterol xinafoate and fluticasone propionate (Sal/Flu), causing many adverse reactions due to hormones. Magnesium isoglycyrrhizinate (MgIG) is an anti-inflammatory glycyrrhizic acid preparation for treating chronic inflammation, contributing to its structure is similar to steroidal anti-inflammatory drugs. In this study, we successfully established COPD rat model by endotracheal-atomized lipopolysaccharide exposure and cigarette smoke induction, as characterized by lung function decline. We discovered that salmeterol xinafoate/MgIG combination could alleviated lung inflammation infiltration, airway wall thickness (AWT) and the secretion of bronchial mucin MUC5AC of COPD rats more than salmeterol xinafoate, MgIG, or salmeterol xinafoate and fluticasone propionate treatment did, as well as reduced inflammatory cells (white blood cells, neutrophils and lymphocytes) accumulation in bronchoalveolar lavage fluid and decreased TNF-α, IL-6 and IL-1ß production in the serum of COPD rats. Finally, we found that Moreover, the mechanism involved might be related to the suppression of JAK/STAT signaling pathway. Overall, our studies suggested that MgIG might be a potential alternative adjuvant drug for fluticasone propionate for the clinical treatment of patients with COPD.

Influence of Glutathione-S-Transferase A1*B Allele on the Metabolism of the Aromatase Inhibitor, Exemestane, in Human Liver Cytosols and in Patients Treated With Exemestane.

Exemestane (EXE) is used to treat postmenopausal women diagnosed with estrogen receptor positive (ER+) breast cancer. A major mode of metabolism of EXE and its active metabolite, 17ß-dihydroexemestane, is via glutathionylation by glutathione-S-transferase (GST) enzymes. The goal of the present study was to investigate the effects of genetic variation in EXE-metabolizing GST enzymes on overall EXE metabolism. Ex vivo assays examining human liver cytosols from 75 subjects revealed the GSTA1 *B*B genotype was associated with significant decreases in S-(androsta-1,4-diene-3,17-dion-6α-ylmethyl)-L-glutathione (P = 0.034) and S-(androsta-1,4-diene-17ß-ol-3-on-6α-ylmethyl)-L-gutathione (P = 0.014) formation. In the plasma of 68 ER+ breast cancer patients treated with EXE, the GSTA1 *B*B genotype was associated with significant decreases in both EXE-cysteine (cys) (29%, P = 0.0056) and 17ß-DHE-cys (34%, P = 0.032) as compared with patients with the GSTA1*A*A genotype, with significant decreases in EXE-cys (Ptrend = 0.0067) and 17ß-DHE-cys (Ptrend = 0.028) observed in patients with increasing numbers of the GSTA1*B allele. A near-significant (Ptrend = 0.060) trend was also observed for urinary EXE-cys levels from the same patients. In contrast, plasma and urinary 17ß-DHE-Gluc levels were significantly increased (36%, P = 0.00097 and 52%, P = 0.0089; respectively) in patients with the GSTA1 *B*B genotype. No significant correlations were observed between the GSTM1 null genotype and EXE metabolite levels. These data suggest that the GSTA1*B allele is associated with interindividual differences in EXE metabolism and may play a role in interindividual variability in overall response to EXE. SIGNIFICANCE STATEMENT: The present study is the first comprehensive pharmacogenomic investigation examining the role of genetic variability in GST enzymes on exemestane metabolism. The GSTA1 *B*B genotype was found to contribute to interindividual differences in the metabolism of EXE both ex vivo and in clinical samples from patients taking EXE for the treatment of ER+ breast cancer. Since GSTA1 is a major hepatic phase II metabolizing enzyme in EXE metabolism, the GSTA1*B allele may be an important biomarker for treatment outcomes and toxicities.

The pan-JAK inhibitor LAS194046 reduces neutrophil activation from severe asthma and COPD patients in vitro.

Non-T2 severe asthma and chronic obstructive pulmonary disease (COPD) are airway chronic inflammatory disorders with a poor response to corticosteroids. LAS194046, a novel pan-Janus kinase (JAK) inhibitor, shows inhibitory effects on T2 allergic lung inflammation in rats. In this work we analyze the effects of LAS194046, fluticasone propionate and their combination in neutrophils from non-T2 severe asthma and COPD patients in vitro. Neutrophils from 23 healthy subjects, 23 COPD and 21 non-T2 severe asthma patients were incubated with LAS194046 (0.01 nM-1 µM), fluticasone propionate (0.1 nM-1 µM) or their combination and stimulated with lipopolysaccharide (LPS 1 µM). LAS194046 shows similar maximal % inhibition and potency inhibiting IL-8, MMP-9 and superoxide anion release in neutrophils from healthy, COPD and asthma. Fluticasone propionate suppresses mediator release only in neutrophils from healthy patients. The combination of LAS194046 with fluticasone propionate shows synergistic anti-inflammatory and anti-oxidant effects. The mechanisms involved in the synergistic effects of this combination include the increase of MKP1 expression, decrease of PI3Kδ, the induction of glucocorticoid response element and the decrease of ERK1/2, P38 and JAK2/STAT3 phosphorylation compared with monotherapies. In summary, LAS194046 shows anti-inflammatory effects in neutrophils from COPD and severe non-T2 asthma patients and induces synergistic anti-inflammatory effects when combined with fluticasone propionate.

Cost-effectiveness analysis: fluticasone furoate/umeclidinium/vilanterol for the treatment of moderate to severe chronic obstructive pulmonary disease from the perspective of the Chilean public health system.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is an inflammatory lung disease characterized by long-term breathing problems and airflow limitations. International guidelines recommend using bronchodilators like long-acting beta- and muscarinic antagonists, and inhalational corticosteroids. OBJECTIVES: The cost-effectiveness of single-inhaler triple therapy containing fluticasone furoate/umeclidinium/vilanterol (FF/UMEC/VI) was compared to the treatments Fluticasone Furoate/Vilanterol (FF/VI), Umeclidinio/Vilanterol (UMEC/VI) and Fluticasone Propionate 250 mcg/Salmeterol 25mcg + Tiotropio 18 mcg (FP/SAL/TIO) for patients with COPD from the Chilean public health system perspective. METHODS: A cost-effectiveness analysis was performed, including a deterministic and probabilistic sensitivity analysis over a 25-year time horizon. Two scenarios were assessed to study the effect of a 3%-discount for costs and outcomes on FF/UMEC/VI. RESULTS: The incremental cost-effectiveness (ICER) of FF/UMEC/VI versus FF/VI was $10,076/QALY, being a cost-effective alternative to a threshold of one Gross Domestic Product per capita (GDPpc), while versus FP/SAL/TIO the ICER increased to $50,288/QALY, showing to be a non-cost effective alternative to 1 GDPpc, but at a threshold of 3 GDPpc. CONCLUSION: FF/UMEC/VI appears to be a cost-effective intervention for treating COPD compared to FF/VI. However, FF/UMEC/VI compared to FP/SAL/TIO showed an ICER above the threshold of 1 GDPpc, but, in comparison with lower price, the ICER was below 3 GDPpc.

Biological evaluation of antiproliferative and anti-invasive properties of an androstadiene derivative on human cervical cancer cell lines.

Gynaecological cancers are leading cause of death: breast cancer is the most frequently diagnosed type of malignancies, and cervical neoplasms rank fourth for both incidence and mortality among women worldwide. In one of our previous studies, favourable antiproliferative and antimetastatic properties of a newly synthesized androstane derivative, 17APAD have been demonstrated on breast cancer cell lines with different expression patterns of hormone receptors. The aim of the current study was to investigate the antitumoral potential of this molecule in cervical cancer cell lines, including SiHa cells positive for human papilloma virus (HPV) type 16 and HPV-negative C33A cells. 17APAD exerted pronounced growth-inhibition (with IC50 values ranging from 0.76 to 1.72 µM with considerable cancer selectivity), while cisplatin used as a reference agent yielded higher IC50 values (ranging from 3.69 to 12.43) and less selectivity, as evidenced by MTT assay. The proapoptotic effect and morphological changes induced by 17APAD were detected by Hoechst 33258-propidium iodide or Annexin V-Alexa488-propidium iodide fluorescent double staining methods, supplemented with a caspase-3 activity assay to identify the mechanism behind the programmed cell death induced by 17APAD. Additionally, significant and concentration-dependent elevation of the ratio of cells in the G2/M phase, on the expense of G0/G1 phase, was observed after 48 h of exposure to 17APAD. Besides its potent antiproliferative properties against both cervical cancer cell lines, 17APAD elicited a remarkable inhibition of cell migration and invasion as detected in wound-healing and Boyden chamber assays, respectively. The mechanisms of action underlying the effects of 17APAD on cell proliferation and motility were independent of androgenic activity, as demonstrated by the Yeast Androgen Screen method. Our results provide new evidence for the proapoptotic and anti-invasive properties of 17APAD, suggesting that it is worth of further research, as a promising prototype for designing novel anticancer agents.

Short- and long-term effects of fluticasone furoate/vilanterol in exercising asthmatic adolescents: A randomized and open label trial.

PURPOSE: Relvar® (fluticasone furoate [FF]/vilanterol [VI]) is a once-daily inhaler with bronchodilator effect lasting 24 h. Our aim was to investigate the short- and long-term effects of FF/VI on exercise-induced asthma (EIA) in adolescents. METHODS: Ninety-three adolescent asthmatics aged 12-18 years were referred for evaluation of EIA. Following a positive exercise challenge test (ECT), 22/44 were allocated to a single administration of salbutamol (400 µg) and 22/44 to FF/VI (92/22 µg) in a double-blind method. Thirty-five subjects were reassessed by repeat ECT 30-60 days of FF/VI. RESULTS: Median FEV1 change post-ECT at baseline was -22.8% predicted (interquartile range [IQR] -26.1 and -18.0) for salbutamol and -21.0 (IQR -30.7 and -16.8) for FF/VI. Following bronchodilator, FEV1 improved similarly in both groups. Repeat ECT following 30-60 days of FF/VI resulted in negative ECT in 33/35 subjects; the median decrease in FEV1 of these 35 subjects was 22.6% predicted (IQR 29-18) before, and 4.6% predicted (IQR 8.7-2.5) after 30-60 days of FF/VI treatment (p < 0.0001). CONCLUSIONS: FF/VI is effective in reversing EIA after 15 min in adolescents and in protecting EIA after 30-60 days in adolescents. Larger studies are needed to assess the effect of FF/VI on EIA.

Differential biological effects of aromatase inhibitors: Apoptosis, autophagy, senescence and modulation of the hormonal status in breast cancer cells.

Estrogen receptor-positive (ER+) breast carcinomas are the most common subtype, corresponding to 60% of the cases in premenopausal and 75% in postmenopausal women. The third-generation of aromatase inhibitors (AIs), the non-steroidal Anastrozole (Ana) and Letrozole (Let) and the steroidal Exemestane (Exe), are considered a first-line endocrine therapy for postmenopausal women. Despite their clinical success, the development of resistance is the major setback in clinical practice. Nevertheless, the lack of cross-resistance between AIs hints that these drugs may act through distinct mechanisms. Therefore, this work studied the different effects induced by AIs on biological processes, such as cell proliferation, death, autophagy and senescence. Moreover, their effects on the regulation of the hormonal environment were also explored. The non-steroidal AIs induce senescence, through increased YPEL3 expression, on aromatase-overexpressing breast cancer cells (MCF-7aro), whereas Exe promotes a cytoprotective autophagy, thus blocking senescence induction. In addition, in a hormone-enriched environment, the non-steroidal AIs prevent estrogen signaling, despite up-regulating the estrogen receptor alpha (ERα), while Exe down-regulates ERα and maintains its activation. In these conditions, all AIs up-regulate the androgen receptor (AR) which blocks EGR3 transcription in Exe-treated cells. On the other hand, in hormone-depleted conditions, a crosstalk between AR and ERα occurs, enhancing the estrogenic effects of Exe. This indicates that Exe modulates both ERα and AR, while Ana and Let act as pure AIs. Thus, this study highlights the potential clinical benefit of combining AR antagonists with Exe and discourages the sequential use of Exe as second-line therapy in postmenopausal breast cancer.

Oxymestane, a cytostatic steroid derivative of exemestane with greater antitumor activity in non-estrogen-dependent cell lines.

A new promising steroid derivative of Exemestane (Exe), the drug used for the treatment of estrogen-dependent breast cancer, was synthesized and evaluated against a set of human cancer cell lines. The new compound (Oxymestane-D1, Oxy) was tested comparatively with Exe against colon (C2BBe1, WiDr), liver (HepG2, HuH-7), lung (A549, H1299) and prostate (LNCaP, PC3) human cancer cell lines. Likewise, its effect on human colon normal cells (CCD-841 CoN) and human normal fibroblast cells (HFF-1) was studied. The cytostatic activity of Oxy was also compared with that of the reference cytostatic drugs used in chemotherapy protocols, namely carboplatin, cisplatin, doxorubicin, epirubicin, etoposide, flutamide, 5-fluorouracil, irinotecan, oxaliplatin and sorafenib. In all cell lines tested, Oxy proved to be more powerful cytostatic than Exe. Additionally, the IC50 at 72 h showed a three-fold activity greater than 5-fluorouracil in the WiDr cell line, twice as high as cisplatin for cell line A549 and five times higher than cisplatin for cell line H1299. Also, Oxy surprisingly revealed to induce DNA damage and inhibit the DNA damage response (DDR) proteins ATM, ATR, CHK1 and CHK2. The results obtained allow concluding that Oxy can be a promising anticancer agent to be used in chemotherapy protocols. Furthermore, its ability to inhibit crucial components of DDR can also be useful for the monotherapy or for combination with chemo and/or radiotherapy of cancer.

Exemestane encapsulated polymer-lipid hybrid nanoparticles for improved efficacy against breast cancer: optimization,in vitrocharacterization and cell culture studies.

Polymer-lipid hybrid nanoparticles (PLHNPs) are novel nanoplatforms for the effective delivery of a lipophilic drug in the management of a variety of solid tumors. The present work was designed to develop exemestane (EXE) encapsulated D-alpha-tocopheryl polyethylene glycol succinate (TPGS) based PLHNPs (EXE-TPGS-PLHNPs) for controlled delivery of EXE for breast cancer management. EXE-TPGS-PLHNPs were formulated by single-step nano-precipitation technique and statistically optimized by a 33Box-Behnken design using Design expert®software. The polycaprolactone (PCL;X1), phospholipon 90 G (PL-90G;X2), and surfactant (X3) were selected as independent factors while particles size (PS;Y1), polydispersity index (PDI;Y2), and %entrapment efficiency (%EE;Y3) were chosen as dependent factors. The average PS, PDI, and %EE of the optimized EXE-TPGS-PLHNPs was observed to be 136.37 ± 3.27 nm, 0.110 ± 0.013, and 88.56 ± 2.15% respectively. The physical state of entrapped EXE was further validated by Fourier-transform infrared spectroscopy, differential scanning calorimetry, and powder x-ray diffraction that revealed complete encapsulation of EXE in the hybrid matrix of PLHNPs with no sign of significant interaction between drug and excipients.In vitrorelease study in simulated gastrointestinal fluids revealed initial fast release for 2 h after that controlled release profile up to 24 h of study. Moreover, optimized EXE-TPGS-PLHNPs exhibited excellent stability in gastrointestinal fluids as well as colloidal stability in different storage concentrations. Furthermore, EXE-TPGS-PLHNPs exhibited distinctively higher cellular uptake and time and dose-dependent cytotoxicity against MCF-7 breast tumor cells compared to EXE-PLHNPs without TPGS and free EXE. The obtained results suggested that EXE-TPGS-PLHNPs can be a promising platform for the controlled delivery of EXE for the effective treatment of breast cancer.

Chemical inhibitor anticancer drugs regulate mechanical properties and cytoskeletal structure of non-invasive and invasive breast cancer cell lines: Study of effects of Letrozole, Exemestane, and Everolimus.

Regardless of their target and mechanism, anticancer drugs directly influence biological behavior of cancer cells by activating chemical signaling pathways. Due to the complex interaction between diverse signaling pathways, these drugs may profoundly impact the physical characteristics of cancer cells and regulate their mechanical properties. In this study, the effects of two Aromatase Inhibitor (Letrozole and Exemestane), and one mTOR Inhibitor (Everolimus) on cell mechanical properties, actin content/distribution, and nuclear areas of two invasive and non-invasive breast cancer cell line after 24 h treatment with concentrations previously reported were investigated. While metabolic activity of cell lines was highly affected by drug treatment, significant alterations in Young's modulus of cell bodies, nuclear areas, and actin content and distribution were reported with higher impact on invasive cells. It was concluded that regulation of mechanical behavior of cells by all three drugs emphasizes the cross talk between chemical and physical signaling cascades, and describes a correlation between biological and physical behaviors of cancer cells which might give an insight to a better understanding of mechanisms by which anti-cancer drugs function to enhance their performances.

Discovery of novel 3-hydroxyandrosta-5,7-Diene-17-Carboxylic acid derivatives as anti-inflammatory bowel diseases (IBD) agents.

A series of steroidal compounds based on 3-hydroxyandrosta-5,7-diene-17-carboxylic acid core structure were designed, synthesized and bio-evaluated for their anti-inflammatory potency. Among them, compound 5c, 6f, and 6q effectively inhibited the production of nitric oxide (NO) in lipopolysaccharide (LPS) stimulated RAW 264.7 macrophages. They inhibited the expression of inducible NO synthase (iNOS) and prostaglandin synthase-2 (COX-2) at mRNA level. Compound 6q displayed inhibitory effects on both iNOS and COX-2 expression in a concentration-dependent manner. Furthermore, 6q was found to effectively decrease the mRNA and protein levels of interleukin 6 (IL-6). Mechanically, 6q could potently downregulate NF-κB signaling via suppression of the Akt/PI3K pathway. Moreover, 6q demonstrated high in vivo anti-inflammatory activities in a mouse colitis model induced by dextran sulfate sodium (DSS). Taken together, these data indicate that 6q represents a novel and promising anti-inflammatory bowel diseases (IBD) agent worthy of further investigation.

New Andrastin-Type Meroterpenoids from the Marine-Derived Fungus Penicillium sp.

Three new andrastin-type meroterpenoids penimeroterpenoids A-C (1-3) together with two known analogs (4 and 5) were isolated from the cultures of the marine-derived Penicillium species (sp.). The structures of the new compounds were elucidated on the basis of 1- and 2-dimensional (1D/2D) Nuclear Magnetic Resonance (NMR) spectroscopic and mass spectrometric analysis. The absolute configurations of 1-3 were determined by comparison of experimental and calculated electronic circular dichroism (ECD) spectra. Compound 1 showed moderate cytotoxicity against A549, HCT116, and SW480 cell lines.

Letrozole targets the human ether-a-go-go-related gene potassium current in glioblastoma.

Aberrant expression of human ether-a-go-go-related gene (hERG) potassium channels has been implicated in the pathophysiology of glioblastoma (GBM). Letrozole has demonstrated efficacy in pre-clinical GBM models. The objective of this research was to assess the potential for hERG inhibition by letrozole to mediate efficacy in GBM. hERG currents were assessed using patch-clamp electrophysiology in an overexpression system during treatment with letrozole, exemestane or vehicle (dimethyl sulphoxide). Relative to vehicle, peak hERG tail current density was reduced when treated with 300 nmol/L and 1 µmol/L letrozole but not when treated with exemestane (up to 1 µmol/L). Cell proliferation was assessed in cultured glioblastoma cell lines (U87 and U373) treated with letrozole, exemestane, doxazosin (hERG blocker) or vehicle. Letrozole, but not exemestane, reduced cell proliferation relative to vehicle in U87 and U373 cells. The associations between expression of hERG (KCNH2), aromatase (CYP19A1) and the oestrogen receptors (ESR1 and ESR2) and time to all-cause mortality were assessed in GBM patients within The Cancer Genome Atlas (TCGA) database. hERG expression was associated with reduced overall survival in the TCGA GBM cohort. Future work is warranted to investigate hERG expression as a potential biomarker to predict the therapeutic potential of hERG inhibitors in GBM.