Search Results (4,548)

The development of endocrine resistance represents a major obstacle when treating hormone receptor-positive breast cancer. The tumor microenvironment (TME), represented by cancer-associated fibroblasts (CAFs) in this context, has recently been proposed as a key mediator significantly contributing to resistance against currently available endocrine therapies. The exact mechanisms behind this interaction are not fully understood; specific breast CAF subtypes have been linked to it, such as CAFs lacking the expression of the glycoprotein CD146 or maintaining the expression of CD63. Other proposed mechanisms include signaling pathways aberrantly activated in CAFs, epigenetic modifications mainly in the form of long non-coding RNAs (lncRNAs) and microRNAs (miRNAs), and paracrine signaling, all limiting endocrine modulation effectiveness. Strategies aiming to simultaneously target CAFs and endocrine signaling in luminal breast cancer are currently being developed. Fibroblast growth factor receptor (FGFR) targeting in combination with endocrine inhibition has already entered the clinical trial landscape. However, CAFs are a highly diverse and heterogeneous cell population, making their targeting complex and difficult to implement in clinical practice. Full article

Amino acids are organic compounds that serve as the fundamental building blocks of proteins and are additionally responsible for a multitude of other biological functions. This review synthesizes recent evidence elucidating that amino acids function as vital players in nitrogen transport, stress defense, and perhaps most intriguingly as signaling molecules. For example, glutamate triggers calcium signals through GLR receptors to guide root growth and pollen tubes. Others, like proline and glutathione, protect cells from drought, salt, and oxidative damage. Aromatic and sulfur-containing amino acids also feed into the production of hormones (auxin, ethylene) and a wide range of defense compounds. Beyond metabolism, we highlighted how plants sense amino acid status via ancient sensors such as PII and the TOR pathway, which fine-tune growth and resource allocation. Understanding this hidden side of amino acids opens new doors for agriculture. We discussed how these insights could lead to smarter biostimulants, gene-edited crops with better nutrient efficiency, and nano-based delivery systems. In short, amino acids are not just food for plants—they are signals, shields, and switches that shape how plants grow and cope with stress. Full article

Paclobutrazol (PBZ) is a triazole-type plant growth regulator that interferes with gibberellin (GAs) biosynthesis by blocking the oxidation step that converts ent-kaurene into ent-kaurenoic acid; however, the developmental mechanisms linking GAs restriction with storage organ enlargement remain poorly understood. In potato, PBZ induces compact growth while promoting microtubers (MTs) expansion, suggesting that GAs depletion triggers coordinated developmental reprogramming rather than simply suppressing elongation. Here, we evaluated the phenotypic, histological, and transcriptomic responses associated with PBZ-induced MTs development in Solanum tuberosum L. PBZ treatment, which increased MTs size, suppressed stolon growth, and enhanced starch accumulation, indicating a shift toward storage tissue development. Transcriptomic analysis identified broad PBZ-responsive changes, including enrichment of pathways related to metabolism, ribosome function, carbon metabolism, plant hormone signaling, and cell cycle regulation. Network analyses revealed ATH1-associated modules connected with receptor-like kinases, transcriptional regulators, mitotic regulators, replication-licensing factors and condensin components, supporting coordinated regulation among growth control, localized proliferation, asymmetric division, endoreduplication, and chromatin stability. These patterns were further supported by the absence of a detectable gibberellic acid (GA₃) peak in PBZ-treated samples. These findings support a model in which PBZ-responsive signaling is associated with developmental reprogramming toward radial expansion and reinforcement of storage tissue, providing a regulatory mechanism by which growth repression is coupled to microtube enlargement in potato. Full article

Incretin receptor agonists (IRAs) such as GLP-1-based therapies improve metabolic and cognitive outcomes and enhance brain insulin signaling. One way that IRAs could have these actions is by affecting the blood–brain barrier (BBB); however, IRA-BBB interactions are poorly studied. Here, we examined the ability of insulin and IRAs to affect each other’s transport across the BBB in lean mice. We found that intracerebroventricular (ICV) administration of the insulin receptor antagonist S961 did not affect the blood-to-brain transport of the bioactive fragment of the IRA, ¹²⁵I-dulaglutide (BAF). In contrast, ¹²⁵I-dulaglutide (BAF) co-administered with intravenous (IV) insulin significantly enhanced ¹²⁵I-dulaglutide (BAF) BBB transport into whole brain, olfactory bulb, parietal cortex, and pons, demonstrating insulin-dependent modulation of IRA BBB transport. Regional transport rates for ¹²⁵I-dulaglutide (BAF) across the brain varied by ~2.5-fold, with the fastest transport into the olfactory bulb, frontal cortex, cerebellum, and pons. Co-administration of IV dulaglutide (BAF) did not alter ¹²⁵I-insulin BBB transport rates (K_i) but did reduce reversible insulin binding (V_i) at the BBB by >50%, suggesting rapid effects on BBB insulin receptors. To explore the effects of chronic IRA administration, lean mice were treated with semaglutide for two weeks. Body weight and food intake were unchanged, but female mice showed reduced fasting levels of serum insulin and GLP-1 and decreased insulin transport into whole brain, while male mice showed a reduction in insulin binding at the BBB. Chronic semaglutide also reduced ¹²⁵I-insulin BBB transport in female mice when studied with in situ perfusion, a procedure that removes the immediate influence of serum factors. Together, these findings demonstrate reciprocal and female-selective interactions between IRAs and insulin at the BBB. Acute insulin enhances the BBB transport of an IRA in female mice, whereas chronic IRA exposure selectively impairs insulin BBB transport in females, highlighting the BBB as a dynamic and hormone-sensitive interface with implications for long-term treatment in mouse models and potential for translation impact in humans. Full article

Background: Prostate cancer (PCa) is the most commonly diagnosed malignancy in men and a leading cause of cancer-related mortality worldwide. Growing evidence indicates that metabolic syndrome components, including obesity, insulin resistance, and hyperglycemia, contribute to PCa development, and progression to more aggressive form. At the same time, standard treatments such as androgen deprivation therapy (ADT) and androgen receptor pathway inhibitors (ARPIs) significantly improve oncologic outcomes but are associated with adverse metabolic effects, including increased fat mass, insulin resistance, and sarcopenia, potentially worsening patients’ overall metabolic profile and quality of life. Tumor progression in PCa is strongly driven by androgen receptor (AR) signaling, which is closely linked to cellular metabolic reprogramming, highlighting metabolism as a potential therapeutic target. Aim: The aim of this study was to evaluate and synthesize current evidence on the role of the ketogenic diet (KD) in PCa, with particular emphasis on its interaction with hormonal therapies, underlying metabolic and endocrine mechanisms, and its potential application as an adjunctive strategy in integrated oncologic care. Results: The KD, characterized by high fat and very low carbohydrate intake, induces a metabolic state of ketosis that reduces circulating glucose, insulin, and insulin-like growth factor 1 (IGF-1), potentially counteracting metabolic alterations associated with PCa and its treatments. Preclinical studies consistently demonstrate that carbohydrate restriction and KD can slow tumor growth, modulate key oncogenic pathways such as PI3K/AKT/mTOR, reduce systemic insulin signaling, and enhance survival in prostate cancer models. Additionally, emerging evidence suggests possible synergistic effects when KD is combined with standard therapies, including ADT and immunotherapy. Clinical data, although limited, indicate that low-carbohydrate dietary interventions may improve metabolic parameters and could delay biochemical progression, as suggested by increased prostate-specific antigen (PSA) doubling time. However, results across studies remain heterogeneous, and robust evidence on long-term oncologic outcomes is lacking. Conclusions: Overall, the KD represents a promising but still experimental strategy in PCa management, requiring careful nutritional supervision to avoid adverse effects such as unintended weight loss or sarcopenia. Further well-designed randomized clinical trials are needed to clarify its safety, efficacy, and role in routine clinical practice. Full article

Cardiac safety assessment is an integral part of drug discovery and development. Drug candidates that adversely affect cardiac or hemodynamic function should be discontinued early unless a favorable benefit-risk ratio for patients can be justified. In this hypothesis-generating work, we aimed to develop a conceptual framework for informing early safety risk assessment based on in vitro drug affinities to pharmacological targets. For illustration, we used the drug-induced cardiotoxicity rank (DICTrank) data comprising 1318 drugs with cardiac safety concerns according to FDA labeling. The data was enriched with information on affinity to the most plausible mechanistic targets, clinical drug exposure, and human plasma protein binding. We descriptively identified 18 target classes potentially associated with elevated cardiovascular risk: potassium channels (accounting alone for 20% of the ‘most concern’ safety group); adrenergic, dopamine, serotonin, androgen, sex hormone, and opioid receptors; cyclooxygenase; sodium and calcium channels; muscarinic and glucocorticoid receptors; phosphodiesterase; topoisomerase; angiotensin-converting enzyme; angiotensin II type 1 receptor; monoamine transporters, and acetylcholinesterase. Overall, 80% of the ‘most concern’ drugs compared with only 12% of the ‘no concern’ drugs were associated with these targets in this exploratory descriptive analysis. Concentration–response analyses revealed differences in target potency and free drug exposure that appeared associated with variability in the severity of cardiotoxicity among drugs acting on the same target. This framework demonstrates how in vitro data can be used to benchmark new compounds early in development, enabling the timely discontinuation of candidates associated with substantial risk. Full article

Huanglongbing (HLB), primarily caused by ‘Candidatus Liberibacter asiaticus’ (CLas), threatens global citrus production. Deciphering the molecular interplay between citrus and CLas is crucial for successful control. This review synthesizes current understanding of the molecular mechanisms underlying citrus-CLas interactions, providing a comprehensive overview that spans immune signaling, hormonal and metabolic reprogramming, non-coding RNA-mediated regulation, pathogen effector biology, and emerging biotechnological interventions. We detail the hierarchical host response: initial immune recognition via pattern recognition receptors, triggering reactive oxygen species bursts and calcium signaling. Moreover, hormonal network reprogramming and their complex interplay in defense/susceptibility are examined. Transcriptomic studies have revealed key features of metabolic reprogramming, including suppression of photosynthesis and impairment of phloem function. Additionally, long-term strategies like cell wall reinforcement, accumulation of defensive compounds such as flavonoids and terpenoids, and roles of post-transcriptional regulation of microRNAs are discussed. Conversely, CLas counter-defense, notably effector-mediated immunity suppression and host metabolism manipulation, is also considered. Comparative transcriptomics between tolerant and susceptible varieties identifies tolerance or resistance genes/pathways for breeding and engineering. Despite this progress, critical knowledge gaps remain, particularly regarding the precise molecular mechanisms of CLas immune evasion and effector-mediated suppression, the genetic basis of natural tolerance, and the field-level efficacy of defense priming strategies. Future research directions should integrate single-cell omics, CRISPR/Cas9 editing, nano-enabled delivery, and microbiome engineering to bridge these gaps and accelerate HLB-tolerant/resistant citrus development. This review synthesizes how molecular profiling advances understanding of citrus defense mechanisms against HLB, and underscores the imperative for interdisciplinary research and global collaboration. Full article

Background: Abemaciclib (ABM) in combination with tamoxifen (TAM) is an extremely significant treatment regimen for hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) breast cancer. It is approved for patients to reduce the risk of cancer recurrence. A bioanalytical method for the simultaneous determination of this new anti-breast cancer combination and its pharmacokinetic application has not yet been reported. Methods: An ultra-performance liquid chromatography tandem mass spectrometry (UPLC–MS/MS) method was developed for quantifying ABM, TAM, and its metabolites, including abemaciclib active metabolites M2, M18, and M20 and tamoxifen active metabolite N-desmethyl tamoxifen (NDTAM), in rat plasma using econazole as the internal standard (IS). Chromatographic separation was achieved on a Kinetex C18 column (100 × 2.1 mm ID, 2.6 µm) using gradient elution with 5 mM ammonium formate in water (eluent A) and 5 mM ammonium formate in water/methanol (1:9, v/v, eluent B) at a flow rate of 0.4 mL/min. Detection was performed on a TSQ Fortis Plus mass spectrometer employing multiple reaction monitoring mode under positive electrospray ionization. Results: The developed method was validated according to the guidance of the FDA. Linearity in rat plasma (ng/mL) was achieved from 1 to 1000 for ABM, TAM, and M20; 3 to 1000 for M2; 5 to 500 for M18; and 1 to 500 for NDTAM; with correlation coefficients ranging from 0.9991 to 0.9931 for all analytes using a weighting factor of 1/X². The lower limit of detection (LLOD) ranged between 0.3 and 1.5 ng/mL for all drugs. The accuracy ranged from 96 to 108% and the precision was less than 7.6% RSD for all analytes. For the first time, the newly developed approach was effectively used in a pharmacokinetic study on the simultaneous oral administration of ABM and TAM in rats that received 30.0 mg/kg of ABM and 8.0 mg/kg of TAM. Conclusions: To the best of our knowledge, this is the first reported UPLC–MS/MS method for the assay of ABM, TAM, and its active metabolites in plasma. This method offers a bioanalytical tool for assessing the pharmacokinetics of ABM and TAM. Therefore, this study makes a definite significant contribution to the field of bioanalytical research. Further validation in human plasma is required for future clinical or therapeutic drug monitoring applications, as the approach was developed in an animal model. Full article

Endometriosis is a chronic, estrogen-dependent disorder defined by ectopic endometrial-like tissue growth, persistent inflammation, and aberrant innervation. Emerging evidence indicates that disease progression and symptom severity are driven by a reciprocal interaction between hormonal dysregulation and neuroinflammatory signaling. This narrative review synthesizes human-based mechanistic and clinical evidence on the hormonal–neuroinflammatory interface in endometriosis, drawing on peer-reviewed publications retrieved from PubMed and Scopus through November 2025. The publications comprised studies using data from patient-derived tissues, primary endometriotic cells, and clinical cohorts. Several convergent molecular nodes at this interface were identified: the prostaglandin E₂–prostaglandin E receptor 2/prostaglandin E receptor 4–aromatase axis, estrogen receptor beta—nuclear factor kappa B signaling, interleukin-6/signal transducer and activator of transcription 3-mediated fibrosis, neurotrophin pathways, transient receptor potential channels (TRPV1/TRPA1), and neurokinin 1 receptor signaling. In this integrated model, endocrine dysfunction fuels neuroinflammation, which in turn impairs steroid responsiveness. This cycle explains the frequent pain–lesion mismatch and the persistence of symptoms despite standard hormonal suppression. Targeting these druggable interface pathways enables better patient stratification and more effective combination therapies for endometriosis. Full article

Polycystic ovarian syndrome (PCOS) affects over 116 million women globally and is typically linked with excess androgens such as testosterone. Many patients, however, display classic PCOS symptoms despite normal serum androgen. One proposed mechanism for these cases involves a shortened CAG (i.e., encodes glutamine) repeat length in the androgen receptor (AR) gene, which increases AR activity without elevating testosterone. Fewer glutamine repeats alter the AR’s N-terminal domain and may contribute to strengthened interactions with co-activators and enhanced transcription of androgen-regulated genes. Heightened AR activity in hypothalamus neurons stimulates increased pulsatile release of gonadotropin-releasing hormone (GnRH), which disrupts pituitary secretion dynamics and favors luteinizing hormone (LH) over follicle-stimulating hormone (FSH). This altered LH/FSH ratio leads to impaired folliculogenesis, anovulation and other hallmark PCOS symptoms. Targeting AR activity directly, for example by using compounds that covalently modify the AR N-terminal domain to suppress activity, may therefore offer a more precise treatment strategy for PCOS. Full article

Dioxins are highly persistent organic pollutants that exist in soil. Their hydrophobic and lipophilic characteristics facilitate long-term stability, posing high risks to the ecosystem and human health. They can be released by different sources, such as the incineration of waste materials, industrial activities, the production of pesticides, and natural or accidental events like forest fires. Dioxins accumulate in food chains and persist in the environment because dioxins are less volatile as well as chemically stable and can strongly bind to organic matter. The accumulation and persistence of dioxins in aquatic and terrestrial systems make them a significant threat to the environment, even at very low concentrations. This review explains the key sources of dioxin-contaminated soil, including industrial emissions and atmospheric deposition, and assesses the associated risks. The transport, places of contamination, and overall status of dioxins are also highlighted in this study. The review also examines the mechanisms of dioxin toxicity, focusing on their interference with hormonal functions and gene expression, as mediated through the aryl hydrocarbon receptor (AhR). This AhR activation leads to gene responses and causes immunotoxicity, endocrine disruption, and oxidative stress. Furthermore, various remediation strategies like biological, physical, and chemical remediation are discussed here as effective approaches for reducing ecological and health risks and promoting soil sustainability. Full article

Introduction: Breast cancer is one of the major killers among malignant conditions worldwide, affecting one out of 10 women in industrialized countries and being the leading cause of cancer-related morbidity and mortality in women. The relationships between risk factors and breast cancer development are not exactly known. The selection of the UBC9 gene and its c.73G>A polymorphism (rs11553473) in breast cancer studies is justified by the gene’s critical role in sumoylation, its impact on DNA repair, and its association with aggressive tumor characteristics. UBC9 (SUMO-conjugating enzyme) is frequently overexpressed in breast cancer, often 5–8-fold higher than in normal tissues, where it promotes tumor proliferation, invasion, and metastasis, often in a sumoylation-independent manner. Aim: In the present work, the association of polymorphism in the UBC9 genes c.73G>A with breast cancer risk was investigated. Materials and Methods: In the reported study, paraffin-embedded tumor tissue was collected from women with lymph node-negative (n = 59) and lymph node-positive (n = 41) ductal breast carcinoma. Samples from age-matched, cancer-free women (n = 100) served as controls. The genotypes of the UBC9 c.73G>A polymorphism were determined by ASO-PCR methods. Results: In the present work, a significant positive association between the UBC9 c.73G>A G/A genotype and breast cancer is demonstrated. The variant A allele of UBC9 increased breast cancer risk. Some correlation was observed between the genotypes of UBC9 polymorphism and breast cancer invasiveness. A statistically significant increase was observed regarding G/A heterozygote frequency in stage II patients, according to Bloom–Richardson classification. There were no significant differences in genotype distribution among subgroups defined by TNM stage, histological grade, hormone receptor status, or HER-2 expression. Conclusions: In conclusion, the reported study indicates that the polymorphisms of the UBC9 gene may be positively associated with the incidence of breast cancer. However, further research is needed on larger study populations. Full article

Background/Objectives: The prognostic significance of the uric acid-to-albumin ratio (UAR) in patients with hormone receptor-positive (HR+) and human epidermal growth factor receptor 2-negative (HER2−) metastatic breast cancer treated with cyclin-dependent kinase 4/6 (CDK4/6) inhibitors has not been adequately investigated. This study aimed to investigate the association between baseline UAR and survival outcomes in this patient population. Methods: This retrospective study included HR-positive/HER2-negative metastatic breast cancer patients treated with ribociclib or palbociclib at Necmettin Erbakan University between May 2020 and April 2025. UAR was calculated by dividing the serum uric acid level (mg/dL) by the serum albumin level (g/dL). Based on receiver operating characteristic (ROC) analysis, the optimal cut-off value for UAR was identified as 1.0 (AUC = 0.67; sensitivity 68%; specificity 58%). Patients were subsequently classified into two groups as UAR < 1 and UAR ≥ 1. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan–Meier method and compared with the log-rank test. Independent prognostic factors were evaluated using Cox regression analyses. Results: A total of 118 eligible patients were included in the analysis, including 34 (28.8%) in the UAR < 1 group and 84 (71.2%) in the UAR ≥ 1 group. The proportion of postmenopausal patients was significantly higher in the UAR ≥ 1 group (p = 0.01). Kaplan–Meier analysis showed that median PFS was not reached in the UAR < 1 group, whereas it was 33.05 months in the UAR ≥ 1 group (log-rank p = 0.06). Median OS was not reached in the UAR < 1 group and was 50.7 months in the UAR ≥ 1 group (p = 0.017). Multivariate Cox regression analysis demonstrated that UAR < 1 was associated with improved PFS (HR = 0.65; 95% CI: 0.34–0.89; p = 0.04). Postmenopausal status emerged as an independent adverse prognostic factor for PFS (HR = 1.92; 95% CI: 1.10–4.05; p = 0.04). In addition, UAR < 1 was associated with a reduced risk of mortality in the OS analysis (HR = 0.61; 95% CI: 0.26–0.87; p = 0.01). Conclusions: Lower baseline UAR was associated with more favorable survival outcomes in HR-positive/HER2-negative metastatic breast cancer patients treated with CDK4/6 inhibitors. As an inexpensive and easily accessible biomarker derived from routine laboratory parameters, UAR may provide additional prognostic information for clinical risk stratification. Full article

The relationship between stress and Parkinson’s disease is regarded as complex and multifaceted, although a direct causal link has not yet been conclusively proven. One prevailing hypothesis is based on the activation of the hypothalamic–pituitary–adrenal (HPA) axis and the consequent elevation of glucocorticoid levels. Prolonged exposure to these hormones may exacerbate oxidative stress, thereby rendering the dopaminergic neurons within the brain’s subcortical structures more susceptible to degeneration. Furthermore, stress may intensify neuroinflammation through the activation of microglia—a mechanism that could constitute a significant factor in the pathogenesis of Parkinson’s disease. Another important concept concerns the direct interaction of stressors with the dopaminergic system. Physiological and psychological stress can alter dopaminergic transmission by affecting both the synthesis and release of dopamine, as well as the sensitivity of dopamine receptors. Severe or chronic stress may contribute to the disruption of dopaminergic mechanisms and accelerate the onset of clinical symptoms in predisposed individuals. Furthermore, many researchers draw attention to the role of stress-induced aggregation of α-synuclein—a key protein implicated in the pathogenesis of Parkinson’s disease. Clinical data suggest a highly probable link between post-traumatic stress disorder and an increased risk of developing Parkinson’s disease, although these findings remain inconclusive. It is possible that stress acts not as a primary cause, but rather as a modifying factor that interacts with genetic predisposition, accelerating or triggering neurodegenerative processes. The aim of our narrative review was to examine these concepts and discuss possible directions for future research into the interaction between stress and Parkinson’s disease. Full article

Cryptorchidism is one of the most frequently diagnosed developmental disorders of the male canine reproductive system, defined as the failure of one or both testes to descend into the scrotum. Physiologically, testicular descent is typically completed by six to eight weeks of age, although some authors extend this period to sixteen weeks. Failure of testicular descent beyond this timeframe is considered pathological. The condition has multiple causes and affects between 1% and 10% of the canine population. Genetics is the most significant factor, indicating the hereditary basis of cryptorchidism. In addition, increasing attention has been directed toward the potential impact of environmental and epigenetic factors on the incidence of cryptorchidism, suggesting that the condition may result from complex interactions between genetic predisposition and external influences. The effect of hormones (such as INSL3 and testosterone), mechanical factors (including narrowing of the inguinal canal, abnormalities of the gubernaculum, and shortening of the spermatic cord), and environmental factors (for example, exposure to external estrogens and maternal stress during pregnancy) all contribute to the development of this disorder. Recent results have emphasized the role of the orexin system, particularly the OX2R receptor, in regulating endocrine and reproductive functions in cryptorchid testes. Computed tomography is increasingly utilized in complex cases due to its high precision in localizing retained testes. Clinically, cryptorchidism may present unilaterally or bilaterally. Unilateral cryptorchidism may preserve partial fertility, whereas bilateral cryptorchidism results in complete infertility. Undescended testes may be located in the abdominal cavity or inguinal canal. Major complications include an increased risk of testicular cancer (Sertoli cell tumors and seminomas) and endocrine disorders leading to feminization. Diagnosis is based on clinical examination and imaging modalities such as ultrasound. Orchiectomy, involving the removal of both the retained and normally descended testicles, is thought to be the gold standard for treatment. This method helps avoid complications and the transmission of the defect to offspring. According to Fédération Cynologique Internationale (FCI) standards, affected individuals should not be used for breeding or shows. Early detection, surgical intervention, and consistent exclusion from breeding programs are the primary strategies for reducing the incidence of this disorder in the canine population. Full article