Search Results (580)

Background/Objectives: Doxorubicin (DOXO) is effective against various types of cancer; however, it is associated with hepatotoxicity that may eventually lead to liver fibrosis, limiting its clinical use. Aurora kinase A (AURKA) has emerged as a crucial regulator of essential cellular processes and a promising target to overcome tumors resistant to some anticancer drugs, including DOXO. However, the potential beneficial effect of targeting AURKA on DOXO-induced toxicities has not been explored yet. Therefore, the current study aimed to explore the potential protective effect of the AURKA-selective inhibitor alisertib on DOXO-induced hepatotoxicity in mice and address the possible underlying mechanism. Methods: Mice were treated with alisertib (10 and 20 mg/kg) daily for five consecutive days and challenged with DOXO (20 mg/kg, i.p.) once on day two. Results: Our findings revealed that alisertib significantly reduced biomarkers of liver dysfunction and oxidative stress elevated by the DOXO challenge. Interestingly, alisertib suppressed DOXO-induced IL-17A upsurge along with NF-κB and STAT3 activation. Alisertib also suppressed the upregulated expression of HIF-1α and VEGF-A as well as PERK activation associated with the DOXO challenge. Moreover, alisertib counteracted DOXO-induced TGF-β1 and α-SMA overexpression in the liver. These beneficial effects of alisertib were further reflected in the histopathological findings, which indicated the ability of alisertib to ameliorate DOXO-induced hepatic necroinflammation and fibrosis. Conclusions: Alisertib mitigates DOXO-induced hepatotoxicity in mice via targeting the IL-17A/NF-κB and IL-17A/STAT3/HIF-1α/VEGF-A signaling pathways, attenuating oxidative stress, inflammation, ER stress, and fibrosis. Full article

Objective: The development of natural and new P-gp modulators to reverse tumor multidrug resistance (MDR). Methods: Test compounds were prepared from the plant Metaplexis japonica, and their ability to reverse P-glycoprotein (P-gp)-mediated MDR was investigated in HepG2/Dox cells. Their effects on P-gp expression and function and their interaction modes with P-gp were also investigated. Results: Natural product 3β,12β,14β, 17β,20(S)-pentahydroxy-5α-pregnan-12β-O-(E)-cinnamate (1) and its new semisynthetic derivative 3β12β,14β,17β,20(S)-pentahydroxy-5α-pregnan-3β-O-nicotinate-12β-O-(E)-cinnamate (1a) were obtained. At non-cytotoxic concentrations of 5 or 10 μM, they significantly reversed the resistance of HepG2/Dox cells to P-gp substrate drugs doxorubicin, paclitaxel, and vinblastine, with reversal folds of 7.1, 118.5, and 198.3 (1), and 18.8, 335.8, and 140.0 (1a), respectively, at 10 μM. Cell apoptosis and expression of caspase 9 were both triggered by the combination of 10 μM of compound 1 or 1a and 500 nM of paclitaxel (p < 0.001). Compound 1 or 1a did not affect P-gp expression, but it did significantly suppress the efflux of Rhodamine 123 out of HepG2/Dox cells (p < 0.001). On the Caco-2 cell monolayer, 1 and 1a were shown to be non-substrates of P-gp, with efflux ratios of 0.83 and 0.89. Molecular docking revealed their strong binding energies (−8.2 and −8.4 kcal/mol) with P-gp, and their direct binding to P-gp was confirmed by their dissociation constants (5.53 µM for 1 and 3.72 µM for 1a), determined using surface plasmon resonance. Conclusions: Compounds 1 and 1a are potential P-gp modulators; they may reverse P-gp-MDR through interacting with P-gp to interfere with substrate binding and transporting, and have the potential to improve the efficacy of paclitaxel or vinblastine drugs for combating P-gp-mediated MDR in tumor cells. Full article

Cancer-associated fibroblasts (CAFs) constitute a heterogeneous population of cells within the tumor microenvironment and are associated with cancer development and drug resistance. The absence of a universal classification for CAFs hinders their research and therapeutic targeting. To define CAF phenotypes, we developed patient-derived cell cultures of breast cancer (BC) and validated and characterized four distinct CAF subtypes (S1–S4) by Costa’s classification. Three out of five primary cell cultures of BC demonstrated different functional features rather than fixed cellular states due to the plasticity of the CAF phenotype. CAF crosstalk with cancer cells supported their survival in the presence of anticancer drugs. Based on the analysis of the cytotoxic effect of doxorubicin, cisplatin and tamoxifen, it was demonstrated that CAF-S4 and CAF-S1 cells were sensitive to the action of all drugs investigated, despite the fact that they possessed different mechanisms of action. CAF-S2 cells exhibited the highest level of resistance to the antitumour agents. Homotypic and heterotypic spheroids with CAFs could be used to model the fibrotic area of BC in vitro. The patient-derived cell cultures of CAFs formed spheroids. Hypoxia-activated CAF-S4 have been shown to stimulate the metastatic potential of triple-negative BC cells in a heterotypic spheroid model. Consequently, this study could be a starting point for the development of novel therapeutic strategies that target CAFs and their interactions with cancer cells. Full article

Continuing our search for bioactive compounds in species from the Juncaceae family, we investigated Juncus tenuis. The structures of five previously undescribed phenanthrenes—tenuins A–E (1–5)—and 14 known phenanthrenes (6–19), along with other components, were isolated and characterized using nuclear magnetic resonance and high-resolution mass spectrometry measurements. The antiproliferative activity of all of the isolated phenanthrenes was evaluated against the human colorectal adenocarcinoma cell lines COLO 205 (doxorubicin-sensitive) and COLO 320 (doxorubicin-resistant), as well as a non-tumorigenic human fibroblast cell line (CCD-19Lu), using the MTT viability assay. Diphenanthrenes 4, 5, and 19 showed the most potent antiproliferative effects, with IC₅₀ values ranging from 7.60 to 17.32 μM; however, these compounds lacked selectivity toward cancer cells. To explore potential chemosensitizing properties, the synergistic effects of the phenanthrenes with the anticancer drug doxorubicin were also examined in the COLO 320 cells. Notably, compound 2 exhibited very strong synergism (CI = 0.021), indicating a highly potent interaction. These findings highlight J. tenuis as a valuable source of phenanthrenes and demonstrate the synergistic anticancer potential of natural phenanthrenes with doxorubicin, offering promising prospects for overcoming multidrug resistance in colorectal cancer therapy. Full article

In this study, a series of novel β-phenylalanine derivatives were synthesised and evaluated for their anticancer activity. The 3-(4-methylbenzene-1-sulfonamido)-3-phenylpropanoic acid (2) was prepared using β-phenylalanine as a core scaffold. The β-amino acid derivative 2 was converted to the corresponding hydrazide 4, which enabled the development of structurally diverse heterocyclic derivatives including pyrrole 5, pyrazole 6, thiadiazole 8, oxadiazole 11, triazoles 9 and 12 with Schiff base analogues 13 and series1,2,4-triazolo [3,4-b][1,3,4]thiadiazines 14. These modifications were designed to enhance chemical stability, solubility, and biological activity. All compounds were initially screened for cytotoxicity against the A549 human lung adenocarcinoma cell line, identifying N-[3-(3,5-dimethyl-1H-pyrazol-1-yl)-3-oxo-1-phenylpropyl]-4-methylbenzenesulfonamide (5) and (E)-N-{2-[4-[(4-chlorobenzylidene)amino]-5-thioxo-4,5-dihydro-1H-1,2,4-triazol-3-yl]-1-phenylethyl}-4-methylbenzenesulfonamide (13b) as the most active. The two lead candidates were further evaluated in H69 and H69AR small cell lung cancer lines to assess activity in drug-sensitive and multidrug-resistant models. Schiff base 13b containing a 4-chlorophenyl moiety, retained potent antiproliferative activity in both H69 and H69AR cells, comparable to cisplatin, while compound 5 lost efficacy in the resistant phenotype. These findings suggest Schiff base derivative 13b may overcome drug resistance mechanisms, a limitation commonly encountered with standard chemotherapeutics such as doxorubicin. These results demonstrate the potential role of β-phenylalanine derivatives, azole-containing sulphonamides, as promising scaffolds for the development of novel anticancer agents, particularly in the context of lung cancer and drug-resistant tumours. Full article

Phthalocyanines (Pcs) are well-established photosensitizers in photodynamic therapy, valued for their strong light absorption, high singlet oxygen generation, and photostability. Recent advances have focused on covalently conjugating Pcs, particularly zinc phthalocyanines (ZnPcs), with a wide range of small bioactive molecules to improve selectivity, efficacy, and multifunctionality. These conjugates combine light-activated reactive oxygen species (ROS) production with targeted delivery and controlled release, offering enhanced treatment precision and reduced off-target toxicity. Chemotherapeutic agent conjugates, including those with erlotinib, doxorubicin, tamoxifen, and camptothecin, demonstrate receptor-mediated uptake, pH-responsive release, and synergistic anticancer effects, even overcoming multidrug resistance. Beyond oncology, ZnPc conjugates with antibiotics, anti-inflammatory drugs, antiparasitics, and antidepressants extend photodynamic therapy’s scope to antimicrobial and site-specific therapies. Targeting moieties such as folic acid, biotin, arginylglycylaspartic acid (RGD) and epidermal growth factor (EGF) peptides, carbohydrates, and amino acids have been employed to exploit overexpressed receptors in tumors, enhancing cellular uptake and tumor accumulation. Fluorescent dye and porphyrinoid conjugates further enrich these systems by enabling imaging-guided therapy, efficient energy transfer, and dual-mode activation through pH or enzyme-sensitive linkers. Despite these promising strategies, key challenges remain, including aggregation-induced quenching, poor aqueous solubility, synthetic complexity, and interference with ROS generation. In this review, the examples of Pc-based conjugates were described with particular interest on the synthetic procedures and optical properties of targeted compounds. Full article

Human adipose-derived stem cells (hASCs) are widely used in regenerative medicine due to their accessibility and high proliferative capacity. Platelet lysate (PL) has recently emerged as a promising alternative to fetal bovine serum (FBS), offering superior cell expansion potential; however, the molecular basis for its efficacy remains insufficiently elucidated. In this study, we performed RNA sequencing to compare hASCs cultured with PL or FBS, revealing a significant upregulation of genes related to stress response and cell proliferation under PL conditions. These findings were validated by RT–qPCR and supported by functional assays demonstrating enhanced cellular resilience to oxidative and genotoxic stress, reduced doxorubicin-induced senescence, and improved antiapoptotic properties. In a murine wound model, PL-treated wounds showed accelerated healing, characterized by thicker dermis-like tissue formation and increased angiogenesis. Immunohistochemical analysis further revealed elevated expression of chk1, a DNA damage response kinase encoded by CHEK1, which plays a central role in maintaining genomic integrity during stress-induced repair. Collectively, these results highlight PL not only as a viable substitute for FBS in hASC expansion but also as a bioactive supplement that enhances regenerative efficacy by promoting proliferation, stress resistance, and antiaging functions. Full article

Dark sweet cherries (DSC) phytochemicals have emerged as a promising dietary strategy to combat triple-negative breast cancer (TNBC). This study explored the effects of DSC extract rich in anthocyanins (ACN) as a chemopreventive agent and as a complement to doxorubicin (DOX) in treating TNBC tumors and metastasis using a 4T1 syngeneic animal model. Initiating ACN intake as a chemopreventive one week before 4T1 cell implantation significantly delayed tumor growth without any signs of toxicity. Both DOX treatment and the combination of DOX-ACN effectively delayed tumor growth rate, but DOX-ACN allowed for body weight gain, which was hindered by DOX alone. As a chemopreventive, ACN downregulated metastasis- and immune-suppression-related genes, including STAT3, Snail1, mTOR, SIRT1, TGFβ1, IKKβ, and those unaffected by DOX alone, such as HIF, Cd44, and Rgcc32. Correlations between mRNA levels seen in control and DOX groups were absent in ACN and/or DOX-ACN groups, indicating that Cd44, mTOR, Rgcc32, SIRT1, Snail1, and TGFβ1 may be ACN targets. The DOX-ACN treatment showed a trend toward enhanced efficacy involving CREB, PI3K, Akt-1, and Vim compared to DOX alone. Particularly, ACN significantly suppressed lung metastasis compared to the other groups. ACN also decreased the frequency and incidence of metastasis in the liver, heart, kidneys, and spleen, while their metastatic area (%) and number of breast cancer (BC) metastatic tumor nodules were lowered without reaching significance. Further research is needed to explore the efficacy of combining ACN with drug therapy in the context of drug resistance. Full article

Regulatory T cells (Tregs) have multiple roles in the tumor microenvironment (TME), which maintain a balance between autoimmunity and immunosuppression. This research aimed to investigate the interaction between cancer stemness and Regulatory T cells (Tregs) in the breast cancer tumor immune microenvironment. Breast cancer stemness was calculated using one-class logistic regression. Twelve main cell clusters were identified, and the subsequent three subsets of Regulatory T cells with different differentiation states were identified as being closely related to immune regulation and metabolic pathways. A prognostic risk model including MEA1, MTFP1, PASK, PSENEN, PSME2, RCC2, and SH2D2A was generated through the intersection between Regulatory T cell differentiation-related genes and stemness-related genes using LASSO and univariate Cox regression. The patient’s total survival times were predicted and validated with AUC of 0.96 and 0.831 in both training and validation sets, respectively; the immunotherapeutic predication efficacy of prognostic signature was confirmed in four ICI RNA-Seq cohorts. Seven drugs, including Ethinyl Estradiol, Epigallocatechin gallate, Cyclosporine, Gentamicin, Doxorubicin, Ivermectin, and Dronabinol for prognostic signature, were screened through molecular docking and found a synergistic effect among drugs with deep learning. Our prognostic signature potentially paves the way for overcoming immune resistance, and blocking the interaction between cancer stemness and Tregs may be a new approach in the treatment of breast cancer. 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

Breast cancer is the most frequently diagnosed cancer among women. In recent years, immunotherapy, a key targeted treatment strategy, has gained prominence in the management of this disease. Immune cells within the tumor microenvironment can significantly affect treatment outcomes. Among immunotherapeutic approaches, or programmed death protein 1(PD-1) and programmed death-ligand 1(PD-L1)-targeted therapies are increasingly recognized for their role in modulating cancer–immune system interactions. This study investigated the impact of PD-1/PD-L1 pathway inhibition on the expression of drug resistance-related proteins in an in vitro breast cancer model incorporating immune cells. MDA-MB-231 and MCF-7 cell lines were used as breast cancer cells, while THP-1 and Jurkat cells represented monocytes and lymphocytes, respectively. The effects of paclitaxel (PTX), doxorubicin (Dox), and PD-1/PD-L1 inhibitors (BMS-1166 and Human PD-L1 Inhibitor IV (PI4)) on cell viability were evaluated using an MTT assay, and the IC₅₀ values were determined. Flow cytometry was used to analyze PD-1/PD-L1 expression and the drug resistance proteins ABCG2 (ATP-binding cassette sub-family G member 2, breast cancer resistance protein), MDR-1 (multidrug resistance protein 1), and MRP-1 (multidrug resistance-associated protein 1) across co-culture models. Based on the results, Dox reduced PD-L1 expression in all groups except for MDA-MB-231:THP-1, while generally lowering drug resistance protein levels, except in MDA-MB-231:Jurkat. BMS-1166 significantly decreased cell viability and enhanced chemotherapy-induced cytotoxicity. Interestingly, in the MDA-MB-231:Jurkat co-culture, both inhibitors reduced PD-L1 but increased drug resistance protein expression. Paclitaxel’s effect on PD-L1 varied depending on the immune context. These findings highlight that PD-1/PD-L1 inhibitors and chemotherapeutic agents differentially affect PD-L1 and drug resistance-related protein expression depending on the immune cell composition within the tumor microenvironment. Full article

Background/Objectives: Effective and targeted delivery of doxorubicin (DOX) remains a significant challenge due to its dose-limiting cardiotoxicity and systemic side effects. Liposomal formulations like Doxil^® have improved tumor targeting and reduced toxicity, but issues such as limited stability, poor release control, and insufficient site-specific delivery persist. As a result, there is a growing interest in advanced drug delivery systems, particularly polymeric nanocarriers, which offer biocompatibility, tunable properties, and ease of fabrication. Methods: This review is organized into two key sections. The first section provides a comprehensive overview of DOX, including its mechanism of action, clinical challenges, and the limitations of current chemotherapy approaches. The second section highlights recent advances in polymeric nanocarriers for DOX delivery, focusing on polymeric micelles as well as other promising systems like hydrogels, dendrimers, polymersomes, and polymer–drug conjugates. Results: Initial discussions explore current strategies enhancing DOX’s clinical translation, including methods to address cardiotoxicity and multidrug resistance. The latter part presents recent studies that report improved drug loading efficiency in polymeric nanocarriers through techniques such as core/shell modifications, enhanced hydrophobic interactions, and polymer–drug conjugation. Conclusions: Despite notable progress in polymeric nanocarrier-based DOX delivery, challenges like limited circulation time, immunogenicity, and manufacturing scalability continue to hinder clinical application. Continued innovation in this field is crucial for the development of safe, effective, and clinically translatable polymeric nanocarriers for cancer therapy. Full article

Anthracyclines have been clinically well established in cancer chemotherapy for decades. The main limitations of this drug class are the development of resistance and severe side effects. In the present investigation, we analyzed 30 anthracyclines in a panel of 59 cell lines of the National Cancer Institute, USA. The log₁₀IC₅₀ values varied from −10.49 M (3′-deamino-3′-(4″-(3″-cyano)morpholinyl)-doxorubicin, 1) to −4.93 M (N,N-dibenzyldaunorubicin hydrochloride, 30). Multidrug-resistant NCI-ADR-Res ovarian cancer cells revealed a high degree of resistance to established anthracyclines (between 18-fold to idarubicin (4) and 166-fold to doxorubicin (13) compared to parental, drug-sensitive OVCAR8 cells). The resistant cells displayed only low degrees of resistance (1- to 5-fold) to four other anthracyclines (7, 18, 28, 30) and were even hypersensitive (collaterally sensitive) to two compounds (1, 26). Live cell time-lapse microscopy proved the cross-resistance of the three chosen anthracyclines (4, 7, 9) on sensitive CCRF/CEM and multidrug-resistant CEM/ADR5000 cells. Structure–activity relationships showed that the presence of tertiary amino functions is helpful in avoiding resistance, while primary amines rather increased resistance development. An α-aminonitrile function as in compound 1 was favorable. Investigating the mRNA expression of 49 ATP-binding cassette (ABC) transporter genes showed that ABCB1/MDR1 encoding P-glycoprotein was the most important one for acquired and inherent resistance to anthracyclines. Molecular docking demonstrated that all anthracyclines bound to the same binding domain at the inner efflux channel side of P-glycoprotein with high binding affinities. Kaplan–Meier statistics of RNA sequencing data of more than 8000 tumor biopsies of TCGA database revealed that out of 23 tumor entities high ABCB1 expression was significantly correlated with worse survival times for acute myeloid leukemia, multiple myeloma, and hepatocellular carcinoma patients. This indicates that ABCB1 may serve as a prognostic marker in anthracycline-based chemotherapy regimens in these tumor types and a target for the development of novel anthracycline derivatives. Full article

Background: Targeted therapies, such as endocrine agents, have significantly improved outcomes for patients with estrogen receptor alpha-positive (ERα+) breast cancer. Unfortunately, for patients with triple-negative breast cancer (TNBC), which lack expression of ERα and HER2, there remains a dearth of targeted adjuvant agents. We discovered that estrogen receptor beta (ERβ) is expressed in approximately 20% of TNBC cases, and its activation has been shown to inhibit proliferation, invasion, and migration in preclinical models. However, it remains unclear whether ERβ-targeted therapies maintain efficacy following the development of chemoresistance. Methods: To address this question, we generated ERβ+ TNBC cell line models with acquired resistance to paclitaxel or doxorubicin. We then assessed their response to ERβ-targeted therapies and analyzed transcriptomic changes associated with chemoresistance and ERβ ligand treatment. Results: Chemotherapy-resistant ERβ+ TNBC cells retained sensitivity to ERβ-targeted therapies and, in some cases, exhibited enhanced responsiveness. ERβ expression did not compromise chemotherapy efficacy in treatment-naïve cells. Chemotherapy-resistant cells had a vastly altered transcriptome and surprisingly, a heavily reduced ERβ transcriptome, compared to sensitive cells despite the maintenance of ERβ-driven anti-neoplastic activity. Conclusions: These findings suggest that ERβ remains a relevant drug target in chemotherapy-refractory disease and has aided in the refinement of a minimal ERβ transcriptomic signature associated with response to ERβ-targeting agents, further informing the primary mechanisms through which ERβ elicits its tumor suppressive effects. Full article

Hepatocellular carcinoma (HCC) is still a leading cause of cancer-related mortality worldwide, characterized by poor prognosis and limited therapeutic efficacy of conventional chemotherapeutics such as doxorubicin. Phytochemicals are promising adjuvants in cancer therapy due to their multi-targeted effects. In this in vitro study, we investigated the impact of a methanol–water extract (70:30 v/v, MET70) from Muscari comosum bulbs, rich in polyphenols and flavonoids, on doxorubicin-treated HepG2 human hepatoma cells. Co-treatment with MET70 increased intracellular reactive oxygen species (ROS) associated with downregulation of Nrf2 signaling, suppression of antioxidant enzymes (SOD2, GPX-1) and decreased mitochondrial UCP2 expression. MET70 modulated the inflammatory response induced by doxorubicin by decreasing TNF-α and increasing IL-6 expression. MET70 also promoted protein homeostasis through PDIA2 upregulation without exacerbating endoplasmic reticulum stress and inhibited autophagy by reducing Beclin-1 levels, contributing to increased chemosensitivity. Moreover, MET70 downregulated ABCC1 expression, suggesting a role in overcoming multidrug resistance. All these findings demonstrate that Muscari comosum extract enhances doxorubicin efficacy by targeting redox balance, inflammatory signaling, autophagy, and drug resistance, offering a promising redox-based strategy for improving HCC therapy. However, further studies should be performed in vivo. Full article