The binding mechanism of molecular interaction between bicalutamide and human serum albumin (HSA) in a pH 7.4 phosphate buffer was studied using various spectroscopic techniques in combination with molecular modeling. Fluorescence data revealed that the fluorescence quenching of HSA by bicalutamide was a static quenching procedure. The binding constants and number of binding sites were evaluated at different temperatures. The thermodynamic parameters, ΔH and ΔS, were calculated to be 4.30 × 104 J·mol-1 and 245 J·mol-1·K-1, respectively, suggesting that the binding of bicalutamide to HSA was driven mainly by hydrophobic interactions and hydrogen bonds. The displacement studies indicated neither Sudlow\'s site I nor II but subdomain IB as the main binding site for bicalutamide on HSA. The binding distance between bicalutamide and HSA was determined to be 3.54 nm based on the Förster theory. Analysis of circular dichroism, synchronous, and 3D fluorescence spectra demonstrated that HSA conformation was slightly altered in the presence of bicalutamide.

The study presents a thorough and detailed analysis of bicalutamide\'s structural and conformational properties. Quantum chemical calculations were employed to explore the conformational properties of the molecule, identifying significant energy differences between conformers. Analysis revealed that hydrogen bonds stabilise the conformers, with notable variations in torsion angles. Conformers were classified into \'closed\' and \'open\' types based on the relative orientation of the cyclic fragments. NOE spectroscopy in different solvents (CDCl3 and DMSO-d6) was used to study the conformational preferences of the molecule. NOESY experiments provided the predominance of \'closed\' conformers in non-polar solvents and a significant presence of \'open\' conformers in polar solvents. The proportions of open conformers were 22.7 ± 3.7% in CDCl3 and 59.8 ± 6.2% in DMSO-d6, while closed conformers accounted for 77.3 ± 3.7% and 40.2 ± 6.2%, respectively. This comprehensive study underscores the solvent environment\'s impact on its structural behaviour. The findings significantly contribute to a deeper understanding of conformational dynamics, stimulating further exploration in drug development.

Human inflammatory breast cancer (IBC) and canine inflammatory mammary cancer (IMC) are highly aggressive neoplastic diseases that share numerous characteristics. In IBC and IMC, chemotherapy produces a limited pathological response and anti-androgen therapies have been of interest for breast cancer treatment. Therefore, the aim was to evaluate the effect of a therapy based on bicalutamide, a non-steroidal anti-androgen, with doxorubicin and docetaxel chemotherapy on cell proliferation, migration, tumor growth, and steroid-hormone secretion. An IMC-TN cell line, IPC-366, and an IBC-TN cell line, SUM149, were used. In vitro assays revealed that SUM149 exhibited greater sensitivity, reducing cell viability and migration with all tested drugs. In contrast, IPC-366 exhibited only significant in vitro reductions with docetaxel as a single agent or in different combinations. Decreased estrogen levels reduced in vitro tumor growth in both IMC and IBC. Curiously, doxorubicin resulted in low efficacy, especially in IMC. In addition, all drugs reduced the tumor volume in IBC and IMC by increasing intratumoral testosterone (T) levels, which have been related with reduced tumor progression. In conclusion, the addition of bicalutamide to doxorubicin and docetaxel combinations may represent a potential treatment for IMC and IBC.

OBJECTIVE: The economic implications of combining rezvilutamide with androgen deprivation therapy (ADT) remain uncertain, despite the observed survival advantages compared with bicalutamide plus ADT. Therefore, this study evaluates the cost-effectiveness of rezvilutamide plus ADT as the first-line treatment of metastatic hormone-sensitive prostate cancer (mHSPC) from the perspective of the Chinese healthcare system.
METHODS: A partitioned survival model was developed to assess the cost-effectiveness of rezvilutamide combined with ADT. Clinical data were obtained from the CHART trial. Costs and utility values were obtained from local estimate and published literature. Only direct medical costs were included in the model.
METHODS: Rezvilutamide was administered at 240 mg daily or bicalutamide at 50 mg daily until progression.
METHODS: The main outputs of the model included costs and quality-adjusted life years (QALYs), which were used to determine the incremental cost-effectiveness ratio (ICER). One-way and probabilistic sensitivity analysis (PSA) were used to explore model uncertainties.
RESULTS: The rezvilutamide group showed an expected gain of 2.28 QALYs and an incremental cost of US$60 758.82 compared with the bicalutamide group. The ICER for rezvilutamide group versus bicalutamide group was US$26 656.94 per QALY. The variables with the greatest impact on the model results were the utility for progression-free survival state and the price of rezvilutamide. PSA revealed that rezvilutamide group had 100% probability of being cost-effective at a willingness-to-pay threshold of US$35707.5 per QALY.
CONCLUSIONS: Rezvilutamide in combination with ADT is more cost-effective compared with bicalutamide plus ADT as the first-line treatment of mHSPC from the perspective of the Chinese healthcare system.

Mycobacterium abscessus infections are emerging in cystic fibrosis patients, and treatment success rate in these patients is only 33% due to extreme antibiotic resistance. Thus, new treatment options are essential. An interesting target could be Lsr2, a nucleoid-associated protein involved in mycobacterial virulence. Zafirlukast is a Food and Drug Administration (FDA)-approved drug against asthma that was shown to bind Lsr2. In this study, zafirlukast treatment is shown to reduce M. abscessus growth, with a minimal inhibitory concentration of 16 µM and a bactericidal concentration of 64 µM in replicating bacteria only. As an initial response, DNA condensation, a known stress response of mycobacteria, occurs after 1 h of treatment with zafirlukast. During continued zafirlukast treatment, the morphology of the bacteria alters and the structural integrity of the bacteria is lost. After 4 days of treatment, reduced viability is measured in different culture media, and growth of M. abscessus is reduced in a dose-dependent manner. Using transmission electron microscopy, we demonstrated that the hydrophobic multilayered cell wall and periplasm are disorganized and ribosomes are reduced in size and relocalized. In summary, our data demonstrate that zafirlukast alters the morphology of M. abscessus and is bactericidal at 64 µM. The bactericidal concentration of zafirlukast is relatively high, and it is only effective on replicating bacteria but as zafirlukast is an FDA-approved drug, and currently used as an anti-asthma treatment, it could be an interesting drug to further study in in vivo experiments to determine whether it could be used as an antibiotic for M. abscessus infections.

UNASSIGNED: The presence of bone pain is significantly associated with worse overall survival (OS) in patients with castration-resistant prostate cancer. However, there are few data regarding bone pain and survival outcomes in the context of metastatic, hormone-sensitive prostate cancer (MHSPC).
UNASSIGNED: To compare survival outcomes among patients with MHSPC by presence or absence of baseline bone pain at diagnosis.
UNASSIGNED: This post hoc secondary analysis, conducted from September 1 to December 31, 2023, used patient-level data from SWOG-1216, a phase 3, prospective randomized clinical trial that enrolled patients with newly diagnosed MHSPC from 248 academic and community centers across the US from March 1, 2013, to July 15, 2017. All patients in the intention-to-treat population who had available bone pain status were eligible and included in this secondary analysis.
UNASSIGNED: In the SWOG-1216 trial, patients were randomized (1:1) to receive either androgen deprivation therapy (ADT) with orteronel, 300 mg orally twice daily (experimental group), or ADT with bicalutamide, 50 mg orally daily (control group), until disease progression, unacceptable toxic effects, or patient withdrawal.
UNASSIGNED: Overall survival was the primary end point; progression-free survival (PFS) and prostate-specific antigen (PSA) response were secondary end points. Cox proportional hazards regression models were used for both univariable and multivariable analyses adjusting for age, treatment type, Gleason score, disease volume, Zubrod performance status, and PSA level.
UNASSIGNED: Of the 1279 male study participants, 301 (23.5%) had baseline bone pain at MHSPC diagnosis and 896 (70.1%) did not. Bone pain status was unavailable in 82 patients (6.4%). The median age of the 1197 patients eligible and included in this secondary analysis was 67.6 years (IQR, 61.8-73.6 years). Compared with patients who did not experience bone pain, those with baseline bone pain were younger (median age, 66.0 [IQR, 60.1-73.4] years vs 68.2 [IQR, 62.4-73.7] years; P = .02) and had a higher incidence of high-volume disease (212 [70.4%] vs 373 [41.6%]; P < .001). After adjustment, bone pain was associated with shorter PFS and OS. At a median follow-up of 4.0 years (IQR, 2.5-5.4 years), patients with bone pain had median PFS of 1.3 years (95% CI, 1.1-1.7 years) vs 3.7 years (95% CI, 3.3-4.2 years) in patients without initial bone pain (adjusted hazard ratio [AHR], 1.46; 95% CI, 1.22-1.74; P < .001) and OS of 3.9 years (95% CI, 3.3-4.8 years) vs not reached (NR) (95% CI, 6.6 years to NR) in patients without initial bone pain (AHR, 1.66; 95% CI, 1.34-2.05; P < .001).
UNASSIGNED: In this post hoc secondary analysis of the SWOG-1216 randomized clinical trial, patients with baseline bone pain at MHSPC diagnosis had worse survival outcomes than those without bone pain. These data suggest prioritizing these patients for enrollment in clinical trials, may aid patient counseling, and indicate that the inclusion of bone pain in prognostic models of MHSPC may be warranted.
UNASSIGNED: ClinicalTrials.gov Identifier: NCT01809691.

An accumulation of reactive oxygen species (ROS) in cardiomyocytes can induce pro-arrhythmogenic late Na+ currents by removing the inactivation of voltage-gated Na+ channels including the tetrodotoxin (TTX)-resistant cardiac α-subunit Nav1.5 as well as TTX-sensitive α-subunits like Nav1.2 and Nav1.3. Here, we explored oxidant-induced late Na+ currents in mouse cardiomyocytes and human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) as well as in HEK 293 cells expressing Nav1.2, Nav1.3, or Nav1.5. Na+ currents in mouse cardiomyocytes and hiPSC-CMs treated with the oxidant chloramine T (ChT) developed a moderate reduction in peak current amplitudes accompanied by large late Na+ currents. While ChT induced a strong reduction in peak current amplitudes but only small persistent currents on Nav1.5, both Nav1.2 and Nav1.3 produced increased peak current amplitudes and large persistent currents following oxidation. TTX (300 nM) blocked ChT-induced late Na+ currents significantly stronger as compared to peak Na+ currents in both mouse cardiomyocytes and hiPSC-CMs. Similar differences between Nav1.2, Nav1.3, and Nav1.5 regarding ROS sensitivity were also evident when oxidation was induced with UVA-light (380 nm) or the cysteine-selective oxidant nitroxyl (HNO). To conclude, our data on TTX-sensitive Na+ channels expressed in cardiomyocytes may be relevant for the generation of late Na+ currents following oxidative stress.

Montelukast and zafirlukast, cysteinyl leukotriene receptor antagonists (LTRAs), trigger apoptosis and inhibit cell proliferation of triple‑negative breast cancer MDA‑MB‑231 cells. By contrast, only zafirlukast induces G0/G1 cell cycle arrest. The present study compared the effects of these drugs on proteins regulating cell proliferation, apoptosis, autophagy, and endoplasmic reticulum (ER) and oxidative stress using reverse transcription‑quantitative PCR, western blotting and flow cytometry. The expression of proliferating markers, Ki‑67 and proliferating cell nuclear antigen, was decreased by both drugs. Zafirlukast, but not montelukast, decreased the expression of cyclin D1 and CDK4, disrupting progression from G1 to S phase. Zafirlukast also increased the expression of p27, a cell cycle inhibitor. Both drugs decreased the expression of anti‑apoptotic protein Bcl‑2 and ERK1/2 phosphorylation, and increased levels of the autophagy marker LC3‑II and DNA damage markers, including cleaved PARP‑1, phosphorylated (p)‑ATM and p‑histone H2AX. The number of caspase 3/7‑positive cells was greater in montelukast‑treated cells compared with zafirlukast‑treated cells. Montelukast induced higher levels of the ER stress marker CHOP compared with zafirlukast. Montelukast activated PERK, activating transcription factor 6 (ATF6) and inositol‑requiring enzyme type 1 (IRE1) pathways, while zafirlukast only stimulated ATF6 and IRE1 pathways. GSK2606414, a PERK inhibitor, decreased apoptosis mediated by montelukast, but did not affect zafirlukast‑induced cell death. The knockdown of CHOP by small interfering RNA reduced apoptosis triggered by montelukast and zafirlukast. In conclusion, the effects on cell cycle regulator proteins may contribute to cell cycle arrest caused by zafirlukast. The greater apoptotic effects of montelukast may be caused by the higher levels of activated caspase enzymes and the activation of three pathways of ER stress: PERK, ATF6, and IRE1.

Occupancy of prostate cancer (PCa) cell androgen receptors (AR) signals proliferation, therefore testosterone biosynthesis inhibitors and AR antagonists are important PCa treatments. Conversely, androgen mimics (e.g., prednisone) used in management of PCa might cause proliferation. The balance between PCa proliferation and inhibition predicts treatment success. We used in silico molecular modelling to explore interactions between ARs, androgens (testosterone, dihydrotestosterone (DHT)) and drugs used to treat (bicalutamide) and manage (dexamethasone, prednisone, hydrocortisone) PCa. We found that hydrogen (H-) bonds between testosterone, DHT and Arg752, Asn705 and Thr877 followed by ligand binding cleft hydrophobic interactions signal proliferation, whereas bicalutamide antagonism is via Phe764 interactions. Hydrocortisone, dexamethasone and prednisone H-bond Asn705 and Thr877, but not Arg752 in the absence of a water molecule. Studies with a bicalutamide agonist AR mutation showed different amino acid interactions, indicating testosterone and DHT would not promote proliferation as effectively as via the native receptor. However, hydrocortisone and bicalutamide form Arg752 and Asn705 H-bonds indicating agonism. Our results suggest that as PCa progresses the resulting mutations will change the proliferative response to androgens and their drug mimics, which have implications for the treatment of prostate cancer.

Silicone rubber tissue expanders and breast implants are associated with chronic inflammation, leading to the formation of fibrous capsules. If the inflammation is left untreated, the fibrous capsules can become hard and brittle and lead to formation of capsular contracture. When capsular contracture occurs, implant failure and reoperation is unavoidable. Fibrous capsule formation to medical grade silicone rubber breast implants and polyisobutylene-based electrospun fiber mats attached to silicone rubber with and without an anti-inflammatory therapeutic were compared. A linear polyisobutylene (PIB)-based thermoplastic elastomer is currently applied as a polymer coating for drug release on coronary stents to reduce restenosis. Recent work has created a drug releasing electrospun fiber mat from PIB-based materials. Important to this study, poly(alloocimene-b-isobutylene-b-alloocimene) (AIBA) was electrospun with zafirlukast (ZAF). ZAF is an anti-inflammatory drug that is able to reduce capsule formation and complications to silicone breast implants. Fiber mats are advantageous for local drug delivery because of their high porosity and surface area for drug release. The chief hypothesis was that local release of ZAF from AIBA would lower inflammatory signaling and resulting capsular formation after 90 days in vivo. Electrospun AIBA mats locally released ZAF, lowering inflammation and fibrous capsule development compared to medical grade silicone rubber. Locally and orally released ZAF led to similar results, but the former had much lower concentration that highlights local delivery\'s therapeutic potential. Released ZAF from AIBA fiber mats mitigated inflammation and serves as an alternative to existing clinical approaches.