Search Results (1,297)

Glioblastoma (GBM) is a highly aggressive brain tumor marked by invasive growth and therapy resistance. Tumor cells adapt to hostile conditions, such as hypoxia and nutrient deprivation, by activating survival mechanisms including autophagy and metabolic reprogramming. Among GBM-associated changes, hypersialylation, particularly, the aberrant expression of polysialic acid (PSA), has been linked to increased plasticity, motility, and immune evasion. PSA, a long α2,8-linked sialic acid polymer typically attached to the NCAM, is abundant in the embryonic brain and re-expressed in cancers, correlating with poor prognosis. Here, we investigated how PSA expression was regulated in GBM cells under nutrient-limiting conditions. Serum starvation induced a marked increase in PSA-NCAM, driven by upregulation of the polysialyltransferase ST8SiaIV and an autophagy-dependent recycling of sialic acids from degraded glycoproteins. Inhibition of autophagy or sialidases impaired PSA induction, and PSA regulation appeared dependent on p53 function. Immunohistochemical analysis of GBM tissues revealed co-localization of PSA and LC3, particularly around necrotic regions. In conclusion, we identified a novel mechanism by which GBM cells sustain PSA-NCAM expression via autophagy-mediated sialic acid recycling under nutrient stress. This pathway may enhance cell migration, immune escape, and stem-like properties, offering a potential therapeutic target in GBM. Full article

Colchicine is a potent alkaloid with well-established anti-inflammatory properties. It shows significant promise in treating classic immune-mediated inflammatory diseases, as well as associated cardiovascular diseases, including atherosclerosis. However, its clinical use is limited by a narrow therapeutic window, dose-limiting systemic toxicity, variable bioavailability, and clinically significant drug–drug interactions, partly mediated by modulation of P-glycoprotein and cytochrome P450 3A4 metabolism. This review explores advanced delivery strategies designed to overcome these limitations. We critically evaluate lipid-based systems, such as solid lipid nanoparticles, liposomes, transferosomes, ethosomes, and cubosomes; polymer-based nanoparticles; microneedles; and implants, including drug-eluting stents. These systems ensure targeted delivery, improve pharmacokinetics, and reduce toxicity. Additionally, we discuss chemical derivatization approaches, such as prodrugs, codrugs, and strategic ring modifications (A-, B-, and C-rings), aimed at optimizing both the efficacy and safety profile of colchicine. Combinatorial nanoformulations that enable the co-delivery of colchicine with synergistic agents, such as glucocorticoids and statins, as well as theranostic platforms that integrate therapeutic and diagnostic functions, are also considered. These innovative delivery systems and derivatives have the potential to transform colchicine therapy by broadening its clinical applications while minimizing adverse effects. Future challenges include scalable manufacturing, long-term safety validation, and the translation of research into clinical practice. Full article

Recurrent pregnancy loss (RPL) is defined as the occurrence of two or more pregnancy losses before 20 weeks of gestation. RPL is a common medical condition among reproductive-age women, with approximately 23 million cases reported annually worldwide. Up to 5% of pregnant women may experience two or more consecutive pregnancy losses. Previous studies have investigated risk factors for RPL, including maternal age, uterine pathology, genetic anomalies, infectious agents, endocrine disorders, thrombophilia, and immune dysfunction. However, RPL is a disease caused by a complex interaction of genetic factors, environmental factors (e.g., diet, lifestyle, and stress), epigenetic factors, and the immune system. In addition, due to the lack of research on genetics research related to RPL, the etiology remains unclear in up to 50% of cases. Platelets play a critical role in pregnancy maintenance. This study examined the associations of platelet receptor and ligand gene variants, including integrin subunit beta 3 (ITGB3) rs2317676 A > G, rs3809865 A > T; fibrinogen gamma chain (FGG) rs1049636 T > C, rs2066865 T > C; glycoprotein 1b subunit alpha (GP1BA) rs2243093 T > C, rs6065 C > T; platelet endothelial cell adhesion molecule 1 (PECAM1) rs2812 C > T; and platelet endothelial aggregation receptor 1 (PEAR1) rs822442 C > A, rs12137505 G > A, with RPL prevalence. In total, 389 RPL patients and 375 healthy controls (all Korean women) were enrolled. Genotyping of each single nucleotide polymorphism was performed using polymerase chain reaction–restriction fragment length polymorphism and the TaqMan genotyping assay. All samples were collected with approval from the Institutional Review Board at Bundang CHA Medical Center. The ITGB3 rs3809865 A > T genotype was strongly associated with RPL prevalence (pregnancy loss [PL] ≥ 2: adjusted odds ratio [AOR] = 2.505, 95% confidence interval [CI] = 1.262–4.969, p = 0.009; PL ≥ 3: AOR = 3.255, 95% CI = 1.551–6.830, p = 0.002; PL ≥ 4: AOR = 3.613, 95% CI = 1.403–9.307, p = 0.008). The FGG rs1049636 T > C polymorphism was associated with a decreased risk in women who had three or more pregnancy losses (PL ≥ 3: AOR = 0.673, 95% CI = 0.460–0.987, p = 0.043; PL ≥ 4: AOR = 0.556, 95% CI = 0.310–0.997, p = 0.049). These findings indicate significant associations of the ITGB3 rs3809865 A > T and FGG rs1049636 T > C polymorphisms with RPL, suggesting that platelet function influences RPL in Korean women. Full article

Chromosomal microarray analysis (CMA) was performed for 40 patients with B-ALL undergoing treatment according to the ALL-2016 protocol to investigate the copy number alterations (CNAs) and copy neutral loss of heterozygosity (cnLOH) associated with minimal residual disease (MRD)-positive remission. Aberrations involving over 20,000 genes were identified, and a random forest approach was applied to isolate a subset of genes whose CNAs and cnLOH are significantly associated with poor therapeutic response. We have assembled the triple matched healthy population data and used that data as a reference, but not as a matched control. We identified a recurrent cluster of cnLOH in the 19q13.2–19q13.31 region, significantly enriched in MRD-positive patients (70% vs. 47% in the reference group vs. 16% in MRD-negative patients). This region includes the pregnancy-specific glycoprotein (PSG) gene family and the oncogene ERF, suggesting a potential role in leukemic persistence and treatment resistance. Additionally, we observed significant deletions involving 7p22.3 and 16q13, often as part of large-scale losses affecting almost the entire chromosomes 7 and 16, indicative of global chromosomal instability. These findings highlight specific genomic regions potentially involved in therapy resistance and may contribute to improved risk stratification in B-ALL. Our findings emphasize the value of high-resolution CMA in diagnostics and risk stratification and suggest that PSG genes and other candidate genes could serve as biomarkers for predicting treatment outcomes. Full article

This study evaluated the effects of maternal supplementation with rumen-protected methionine (RPM), alone or combined with rumen-protected choline (RPC) and betaine (RPB), during the periconceptional and prepartum periods on reproductive outcomes and offspring performance in Chios ewes. One hundred synchronized ewes were assigned to three groups—control (no supplementation), M (5.50 g RPM/day), and MCB (3.50 g RPM, 1.60 g RPC, 0.49 g RPB/day)—from day −14 to +14 relative to mating. Blood was collected on days −14, 0, and +14 for ABTS (2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid), ferric-reducing ability (FRAP), and malondialdehyde (MDA), on days 18 and 21 for progesterone, and on day 26 for pregnancy-associated glycoprotein (PAG) detection. Thirty days before and up to lambing, the ewes were further divided into C-C, C-M, C-MCB, M-M, M-C, MCB-MCB, and MCB-C subgroups. Embryonic loss did not differ between groups. FRAP was higher (p < 0.001) in MCB ewes, and ABTS was lower (p < 0.05) in M ewes, in the periconceptional period. Offspring in the C-M, C-MCB, M-M, M-C, and MCB-MCB groups had higher birth weights (p < 0.01), along with increased MDA levels (p < 0.05). The results suggest that maternal methyl donor supplementation during early and/or late gestation enhances antioxidant status, supports embryonic development, and increases birth weight. Full article

Oral anticoagulants, including warfarin, a vitamin K antagonist, have been used for anticoagulation therapy, but their limitations, such as drug interactions and complex dosing, have prompted the development of direct oral anticoagulants (DOACs) like rivaroxaban, apixaban, dabigatran, and edoxaban. This study reviews the interactions of both warfarin and DOACs, particularly those influenced by cytochrome P450 enzymes and P-glycoprotein. Warfarin is metabolized by various cytochrome P450 isoforms, making it vulnerable to interactions with medications and herbs that modulate these enzymes. In contrast, DOACs, while having fewer interactions, are still affected by strong inducers or inhibitors of cytochrome 3A4 and P-glycoprotein, depending on the specific drug. Some herbs may also interfere with these pathways. Continuous monitoring of these interactions is crucial to ensure the safe use of oral anticoagulants. The findings underscore the importance of identifying and understanding these interactions to improve patient safety and guide appropriate anticoagulant therapy. Full article

Drug resistance remains a critical barrier to effective treatment in several cancers, particularly triple-negative breast cancer (TNBC). Estrogen receptor α36 (ERα36), a variant of the estrogen receptor in ER-negative breast cancer cells, plays important roles in cancer cell proliferation. We investigated the role of ERα36 in regulating multidrug resistance protein 1 (MDR1) in MDA-MB-231 human breast cancer cells. The activation of ERα36 by BSA-conjugated estradiol (BSA-E2) increased cell viability under Adriamycin exposure, suggesting its involvement in promoting drug resistance. BSA-E2 treatment significantly reduced the intracellular rhodamine-123 levels by activating the MDR1 efflux function, which was linked to increased MDR1 transcription and protein expression. The mechanical ERα36-mediated BSA-E2-induced activation of EGFR and downstream signaling via c-Src led to an activation of the Akt/ERK pathways and transcription factors, NF-κB and CREB. Additionally, ERα36 is involved in activating Wnt/β-catenin pathways to induce MDR1 expression. The silencing of ERα36 inhibited the BSA-E2-induced phosphorylation of Akt and ERK, thereby reducing MDR1 expression via downregulation of NF-κB and CREB as well as Wnt/β-catenin signaling. These findings demonstrated that ERα36 promotes MDR1 expression through multiple non-genomic signaling cascades, including Akt/ERK-NF-κB/CREB and Wnt/β-catenin pathways, and highlight the role of ERα36 as a promising target to enhance chemotherapeutic efficacy in TNBC. Full article

Background/Objectives: P-glycoprotein (P-gp), an ATP-binding cassette (ABC) transporter, plays a key role in multidrug resistance by actively exporting chemotherapeutic agents and xenobiotics from cells. Overexpression of P-gp significantly reduces intracellular drug accumulation and compromises treatment efficacy. Despite extensive research, clinically approved P-gp inhibitors remain elusive due to toxicity, poor specificity, and limited efficacy. This study investigates DMH1, a selective type I BMP receptor inhibitor, as a novel P-gp inhibitor. Methods: DMH1 cytotoxicity was assessed in P-gp-overexpressing (PC3-TxR, K562/Dox) and P-gp-deficient (PC3) cell lines using MTT assays. P-gp inhibition was evaluated using calcein AM retention and daunorubicin (DNR) accumulation assays. Kinetic analysis determined DMH1’s effect on P-gp-mediated transport (Vmax and Km). ATPase activity assays were performed to assess DMH1’s impact on ATP hydrolysis. Preliminary molecular docking (CB-Dock2) was used to predict DMH1’s binding site on the human P-gp structure (PDB ID: 6QEX). Results: DMH1 showed no cytotoxicity in P-gp-overexpressing or deficient cells. It significantly enhanced intracellular accumulation of Calcein AM and DNR, indicating effective inhibition of P-gp function. Kinetic data revealed that DMH1 reduced Vmax without affecting Km, consistent with noncompetitive, allosteric inhibition. DMH1 also inhibited ATPase activity in a dose-dependent manner. Docking analysis suggested DMH1 may bind to an allosteric site in the transmembrane domain, potentially stabilizing the inward-facing conformation. Conclusions: DMH1 is a promising noncompetitive, allosteric P-gp inhibitor that enhances intracellular drug retention without cytotoxicity, supporting its potential as a lead compound to overcome multidrug resistance and improve chemotherapeutic efficacy. Full article

Background: The number of women veterans has been rising steadily since the Gulf War and many assume the functions of their male counterparts. Women face unique obstacles in their service, and it is imperative that differences in physiology not be overlooked so as to provide better and appropriate care to our women in uniform. Despite this influx and incorporation of female talent, dedicated reports contrasting female and male veterans are rare, outside of specific psychological studies. We therefore attempt to contrast gut constituents, absorption, innate immune system, and nutritional differences to provide a comprehensive account of similarities and differences between female and male veterans, from our single-center perspective, as this has not been carried out previously. Herein, we obtained a detailed roster of commonly used biomedical tests and some novel entities to detect differences between female and male veterans. The objective of this study was to detect differences in the innate immune system and other ancillary test results to seek differences that may impact the health of female and male veterans differently. Methods: To contrast biochemical and sociomedical parameters in female and male veterans, we studied the data collected on 450 female veterans and contrasted them to a group of approximately 1642 males, sequentially from 1995 to 2022, all selected because of above-average risk for CRC. As part of this colorectal cancer (CRC) screening cross-sectional and longitudinal study, we also collected stool, urine, saliva, and serum specimens. We used ELISA testing to detect stool p87 shedding by the Adnab-9 monoclonal and urinary organ-specific antigen using the BAC18.1 monoclonal. We used the FERAD ratio (blood ferritin/fecal p87), a measure of the innate immune system to gauge the activity of the innate immune system (InImS) by dividing the denominator p87 (10% N-linked glycoprotein detected by ELISA) into the ferritin level (the enumerator, a common lab test to assess anemia). FERAD ratios have not been performed elsewhere despite past Adnab-9 commercial availability so we have had to auto-cite our published data where appropriate. Results: Many differences between female and males were detected. The most impressive differences were those of the InImS where males clearly had the higher numbers (54,957 ± 120,095) in contrast to a much lower level in females (28,621 ± 66,869), which was highly significantly different (p < 0.004). Mortality was higher in males than females (49.4% vs. 24.1%; OR 3.08 [2.40–3.94]; p < 0.0001). Stool p87, which is secreted by Paneth cells and may have a protective function, was lower in males (0.044 ± 0.083) but higher in females (0.063 ± 0.116; p < 0.031). Immunohistochemistry of the Paneth cell-fixed p87 antigen was also higher in females (in the descending colon and rectum). In contrast, male ferritin levels were significantly higher (206.3 ± 255.9 vs. 141.1 ± 211.00 ng/mL; p < 0.0006). Females were less likely to be diabetic (29.4 vs. 37.3%; OR 0.7 [0.55–0.90]; p < 0.006). Females were also more likely to use NSAIDs (14.7 vs. 10.7%, OR 1.08 [1.08–2.00]; p < 0.015). Females also had borderline less GI bleeding by fecal immune tests (FITs), with 13.2% as opposed to 18.2% in males (OR 0.68 [0.46–1.01]; p = 0.057), but were less inclined to have available flexible sigmoidoscopy (OR 0.68 [0.53–0.89]; p < 0.004). Females also had more GI symptomatology, a higher rate of smoking, and were significantly younger than their male counterparts. Conclusions: This study shows significant differences with multiple parameters in female and male veterans. Full article

Obesity affects approximately 30% of pregnancies worldwide and is one of the leading metabolic disorders among pregnant women. Maternal obesity is often associated with placental dysfunction and structural alterations, which increase the risk of developing complications. Efflux transporters, including P-glycoprotein (P-gp), may impact placental function and fetal development. Consequently, our research examined the effects of obesity on P-glycoprotein expression in both a rat model and human placental tissue. P-gp expression was measured by RT-PCR and Western blot techniques in human and rat placental tissues. Moreover, we further characterized the high-fat and high-sugar diet (HFHSD)-induced gestational obesity rat model by measuring tissue weights. Significant decreases were observed in fetal, placental, and uterus weights in the obese animals near the end of pregnancy. In obese rats, mRNA and protein expression of placental P-gp showed a reduction on gestation days 15, 20, and 22. A similar P-gp reduction was observed in the term placenta in obese women in mRNA and protein levels. We hypothesize that the reduced expression of P-gp may heighten the susceptibility of both the fetus and placenta to P-gp substrates. This alteration could potentially result in an increased risk of pregnancy complications and obesity-related drug contraindications linked to P-gp transport during pregnancy. Full article

Major Depressive Disorder (MDD) is increasingly linked to disruptions in blood-brain barrier (BBB) integrity, contributing to neuroinflammation and impaired brain homeostasis. While traditional antidepressant therapies often fail to achieve full remission, growing evidence suggests that specific dietary compounds may offer novel avenues for restoring BBB function and improving mental health outcomes. This review explores the potential of selected nutrients—omega-3 fatty acids, vitamin D, sulforaphane, fucoidan, and urolithins—to modulate BBB integrity through anti-inflammatory, antioxidant, and transporter-regulatory mechanisms. These compounds act by reinforcing tight junctions, reducing matrix metalloproteinase activity, and modulating efflux transporters such as P-glycoprotein. Although current evidence is largely preclinical, the mechanistic insights provided in this review support the rationale for integrating nutritional strategies into the management of MDD. Future clinical studies are needed to validate these findings and develop biomarker-driven approaches for targeting the BBB in nutritional interventions for psychiatric disorders. Full article

(1) Background: Overexpression of P-glycoprotein (P-gp) is one mediator of multidrug resistance in cancer. While many studies demonstrate the efficacy of modulating P-glycoprotein expression to increase drug response in cancer cells, the nature of the mathematical relationship between drug sensitivity and P-glycoprotein surface density is not yet characterized. (2) Methods: In this study, we employ siRNA to modulate P-gp expression in two model cell lines and evaluate their steady-state response to three common chemotherapeutics in vitro. Additionally, we model the kinetics of calcein-AM, a P-gp substrate, as a function of P-gp expression. (3) Results: For both cell lines, a robust linear relationship governs chemotherapeutic sensitivity as a function of P-gp expression, demonstrating that characterization of P-gp surface density is a strong indicator of drug response in drug-resistant cells. Furthermore, calcein accumulation and initial influx rate exhibit first-order kinetics with respect to P-gp density, further elucidating the nature of substrate interactions with P-gp-overexpressing cells. When transport kinetics are evaluated using a Michaelis–Menten model, V_max varies with P-gp density according to a first-order relationship. (4) Conclusions: These results establish the mathematical relationships between chemotherapeutic response and substrate influx as a function of P-gp expression and suggest that rational changes in P-gp expression could be used as a predictive measure of drug sensitivity in model cell lines. Full article

Background/Objectives: HIF-1α and ERRα are both implicated in breast cancer progression, yet their functional interplay remains poorly understood. This study investigates their molecular crosstalk in the context of hypoxia-induced drug resistance. Methods: MCF-7 (estrogen receptor, ER-positive) spheroids and CoCl₂-treated SK-BR-3 (ER-negative) cells were used to model tumor hypoxia. Protein expression, coimmunoprecipitation, chromatin immunoprecipitation (ChIP), pharmacological inhibition, and siRNA-mediated gene silencing were employed to assess physical and functional interactions. Immunohistochemistry (IHC) on a tissue microarray (TMA) of 168 invasive breast carcinomas was performed to evaluate clinical relevance. Results: ERRα levels remained unchanged under hypoxia, while its coactivator, Peroxisome Proliferator-Activated Receptor Gamma Coactivator-1 α (PGC-1α), was upregulated. ERRα physically interacted with HIF-1α and was required for HIF-1 transcriptional activity under hypoxic conditions. ChIP assays showed that ERRα-driven overexpression of Permeability glycoprotein 1 (P-gp) and Vascular Endothelial Growth Factor (VEGF) was mediated by HIF-1α binding to the MDR1 and VEGF promoters. Inhibition or silencing of ERRα reversed P-gp overexpression and restored intracellular doxorubicin. TMA analysis confirmed the clinical correlation between ERRα, HIF-1α, and P-gp expression, highlighting the role of ERRα in hypoxia-induced drug resistance. ERRα expression was independent of ER status, suggesting an estrogen-independent function. Conclusions: This study identifies a novel physical and functional interaction between ERRα and HIF-1α that promotes chemoresistance in hypoxic breast tumors. Targeting ERRα may represent a promising therapeutic strategy to overcome drug resistance in aggressive, ER-independent breast cancer subtypes. Full article

P-glycoprotein (P-gp) is a key element of cancer treatment resistance, actively extruding cytotoxic drugs from cells and diminishing their efficacy. While its role at the plasma membrane is well established, its intracellular localization, particularly on lysosomes, is increasingly recognized as a critical contributor to drug resistance. This study investigates four innovative LightSpot fluorescent compounds to detect and quantify both membrane and lysosomal P-gp in Triple-Negative Breast Cancer (TNBC) SUM1315 and DU4475 cell lines. Results highlighted lysosomal P-gp staining by the LightSpot-FL-1, LightSpot-BrX-1, and LightSpot-BdO-1 fluorescent compounds (Mander’s coefficients > 0.8 overlapping with LAMP2 immunostaining). After both cell lines were exposed to Olaparib, a significant increase in P-gp expression level and lysosomal distribution of P-gp was detected. Indeed, after 100 µM Olaparib exposure, LightSpot-FL-1 allowed us to quantify an increase in P-gp-positive lysosome number of 1293 and 334% for SUM1315 and DU4475 cells, respectively, compared to the control. Findings suggest that P-gp may relocate to lysosomes upon drug exposure, highlighting a dual resistance mechanism involving both membrane and lysosomal P-gp. This study demonstrated the potential of LightSpot fluorescent compounds to evaluate P-gp-mediated cell resistance to treatment and emphasized the need to assess global cell P-gp expression to improve cancer diagnosis. Full article

A series of novel N-Mannich bases derived from a dimethylpyridine–1,2,4-triazole hybrid was synthesized and evaluated in vitro for cytotoxic activity on several human gastrointestinal cancer cells (EPG, Caco-2, LoVo, LoVo/Dx, and HT-29). Compound 6 bearing a phenyl group at the N-4 position and a 4-methylphenyl piperazine moiety at the N-2 position of the 1,2,4-triazole-3-thione scaffold exerted good cytotoxic activities on EPG and Caco-2 cell lines, along with pronounced selectivity, showing lower cytotoxicity against normal colonic epithelial cells (CCD 841 CoTr). Further evaluation revealed the good ability of compound 6 to inhibit the efflux function of P-glycoprotein in P-gp-expressing cell lines (HT-29, LoVo, and LoVo/Dx). Moreover, compound 6 induced apoptotic cell death through a significant increase in the caspase-3 and p53 protein levels in HT-29 cells. Finally, the molecular docking method was applied to explain our experimental findings. The molecular modeling study based on Density Functional Theory (DFT) and the Quantum Theory of Atoms in Molecules (QTAIM) analysis provided insight into the geometric and electronic structure properties of the compounds. Full article