Search Results (5,170)

Background/Objectives: β-Lapachone and triapine are compounds with recognized antitumor potential—the former is an ortho-naphthoquinone, and the latter a thiosemicarbazone inhibitor of ribonucleotide reductase. This study aimed to synthesize and evaluate new β-lapachone-based thiosemicarbazones (TSC1–TSC6) as potential antineoplastic agents. Methods: Lapachol was isolated from Tabebuia sp. and used to obtain ortho-naphthoquinones (2–4), which served as precursors for thiosemicarbazones (TSC1–TSC6). NMR and HRMS spectra were used to characterize the compounds. Their cytotoxic activity was evaluated in vitro against murine melanoma (B16–F10), colon carcinoma (CT26.WT), and breast cancer (4T1) cell lines, as well as normal fibroblasts (L929). Pharmacokinetic parameters were predicted in silico using ADMETLab 3.0. Results: β-Lapachone exhibited strong cytotoxicity toward tumor cells with moderate effects on normal cells, while thiosemicarbazones of β-lapachone, TSC1, and TSC3 demonstrated lower potency but greater selectivity. The β-lapachone-3-sulfonic acid showed high activity against melanoma and breast cancer cells and low toxicity toward normal cells, indicating tumor selectivity. In contrast, their thiosemicarbazones, TSC2, TSC4, and TSC6, showed weak or no antiproliferative activity. The 3-iodo-β-lapachone was cytotoxic to both tumor and normal cells, whereas its derivative TSC5 demonstrated moderate activity with reduced toxicity. β-Lapachone, β-lapachone-3-sulfonic acid, TSC1, and TSC3 exhibited favorable ADME profiles (QED ≈ 0.61–0.66), suggesting good oral bioavailability. Conclusions: The β-lapachone-3-sulfonic acid and the β-lapachone-based thiosemicarbazones TSC1 and TSC3 emerged as promising lead candidates, combining tumor selectivity, favorable pharmacokinetic properties, and structural innovation for the development of safer and more effective antineoplastic agents. Full article

Transient receptor potential vanilloid 2 (TRPV2) is a non-selective cation channel involved in diverse physiological and pathological processes. Tranilast has frequently been described and used as a rather specific inhibitor of TRPV2. However, the molecular basis of this inhibition was never been studied in detail. Here, we investigated whether tranilast indeed directly inhibits TRPV2. Rat TRPV2 was expressed in human embryonic kidney (HEK293) cells, and channel function was assessed using whole-cell electrophysiology and calcium imaging in response to established agonists. In parallel, we conducted phagocytosis assays in rat basophilic leukemia (RBL) cells, including a CRISPR/Cas9-generated TRPV2-knockout cell line. Tranilast up to 1 mM did not inhibit TRPV2-mediated currents or calcium influx induced by any agonist. However, when co-applied with the oxidant chloramine T, tranilast diminished oxidation-induced activation of TRPV2. This effect may indicate a general interference of tranilast with redox signaling. Accordingly, tranilast also reduced chloramine T-induced activation of TRPA1 as well as the development of non-inactivating currents of voltage-gated Na⁺ channels. Furthermore, tranilast decreased phagocytic activity in both wildtype and TRPV2-knockout RBL cells. However, the reduction was less pronounced in TRPV2-knockout cells. These findings demonstrate that tranilast does not directly inhibit TRPV2. Instead, tranilast seems to indirectly suppress channel activation by reducing reactive oxygen species (ROS). This refined understanding of how tranilast modulates TRPV2 has important implications for the interpretation of prior and future pharmacological studies targeting TRPV2. Full article

Cyclin-dependent kinase 9 (CDK9) is a key regulator of transcriptional elongation and DNA repair, supporting cancer cell survival by sustaining the expression of oncogenes and anti-apoptotic proteins. Its overexpression in multiple malignancies makes it an attractive target for anticancer therapy. Here, we report a machine learning (ML) based approach to identify novel CDK9 inhibitors. Through systematic data collection and preprocessing, seventy predictive models were developed using five algorithms, two classification settings, and seven molecular representations. The best-performing model was employed to guide a virtual screening (VS) campaign, resulting in the identification of 14 compounds promising for their potential inhibitory effect. Upon enzymatic assays, two molecules with inhibitory activity in the low micromolar range were selected as promising candidates and further tested in three cancer cell lines with distinct genetic backgrounds. These experiments led to the identification of a novel compound exhibiting interesting therapeutic potential, both as a single agent and in combination with Camptothecin (CPT), revealing varying response profiles across the tested cell lines. These results illustrate the power of integrating ML within anticancer drug discovery pipelines and represent a valuable starting point for the development of novel CDK9 inhibitors. Full article

Background: Alzheimer’s disease and Parkinson’s disease are multifactorial disorders causing severe disability, rising with the increase in life expectancy. Currently, the identification of natural compounds useful against these disorders is becoming an urgent necessity. In this study, we used polyphenol-enriched extracts obtained from leaves of Mediterranean plants, which are important in animal feeding (Lotus ornithopodioides, Hedysarum coronarium, Medicago sativa) and in the human Mediterranean diet (Cichorium intybus). Objectives: The aims of this study were as follows: (i) tentative identification of the organic compounds present in the extracts; (ii) determination of their effect on the activity of monoamine oxidase (MAO)-A and MAO-B, key enzymes involved in the metabolism of aminergic neurotransmitters, as well as on protein expression level of these enzymes in cell lines expressing basal MAO-A and MAO-B. Methods: The ability of plant polyphenol extracts to inhibit MAO-A and MAO-B activity was assessed by in vitro enzyme assays. The protein expression level was analyzed by Western blotting. Results: Our data demonstrate that all the extracts behaved as MAO-A and MAO-B inhibitors, although to a different extent and enzyme inhibition mechanism; among them, the extract from L. ornithopodioides induced a decrease in MAO-A protein level in human AGS gastric adenocarcinoma and SH-SY5Y neuroblastoma cell lines. Conclusions: These data reinforce the hypothesis that a plant-based diet and/or integrative supplementation of pharmacological treatments can be considered for preventing and relieving symptoms of neurodegenerative diseases. Full article

Background/Objectives: Synovial sarcoma (SS) is a malignant soft tissue neoplasm with good outcomes in adolescents with localized tumors, but poor outcomes in older adults and in advanced or metastatic cases. Targeting cancer metabolism, such as glutamine metabolism, is a promising therapeutic strategy. In this study, we investigated glutamine dependency in SS and assessed the therapeutic potential of inhibiting the glutamine transporter ASCT2 using V9302. Methods: Immunohistochemistry (IHC) was used to evaluate ASCT2 expression in SS and liposarcoma (LPS) specimen. The effects of glutamine deprivation and V9302 were examined in a SS cell line (HS-SY-II), patient-derived SS cells (SSH1), and a normal cell line (HEK293). Cell viability, apoptosis, and protein expression were assessed using the CCK-8 assay, flow cytometry, and Western blotting, respectively. The therapeutic efficacy of V9302 was evaluated in a xenograft model using IHC. Results: ASCT2 expression was elevated in SS tumor tissues compared with adjacent normal tissues and LPS specimens. Both the HS-SY-II cell line and SSH1 cells exhibited strong glutamine dependency for proliferation. V9302 selectively reduced HS-SY-II cell viability by suppressing the AKT/mTOR signaling pathway and inducing apoptosis via caspase-3 activation, with minimal effects on control cells. In vivo, V9302 administration significantly inhibited tumor growth without inducing systemic toxicity, and IHC of the treated tumors confirmed the suppression of the mTOR pathway and induction of apoptosis. Conclusions: Our findings suggest that SS is a glutamine-dependent malignancy and validate ASCT2 as a promising therapeutic target. The ASCT2 inhibitor V9302 demonstrated therapeutic efficacy both in vitro and in vivo, supporting its potential as a therapeutic agent for SS. Full article

Background/Objectives: Cancer is among the leading causes of mortality worldwide. In 2022 alone, the global cancer death toll stood at 9.74 million. Projections indicate that this figure will rise to 10.4 million by 2025. Methods: A new series of benzimidazolone-bridged hybrid compounds containing thiophene, furan, oxadiazole, piperazine, and coumarin moieties was synthesized and structurally characterized by ¹H-NMR, ¹³C-NMR (APT), and elemental analysis. Their cytotoxic effects were evaluated by MTT assay against human lung (A549), human breast (MCF-7), and human cervical (HeLa) cancer cell lines, and the non-cancerous HEK293 cell line after 48 h exposure over a concentration range of 0.5–250 µM. IC₅₀ values were determined, and Selectivity Indexes (SI) were calculated using HEK293 as the reference normal cell line. Molecular docking studies were carried out using the Glide XP protocol against VEGFR2 (PDB ID: 4ASD) and CDK4–Cyclin D3 (PDB ID: 7SJ3), with sorafenib and abemaciclib as reference inhibitors. Results: The results of anticancer activity were compared with doxorubicin (IC₅₀ ± SD (µM)/SI: 4.3 ± 0.2/1.20 for A549, 6.4 ± 0.37/0.77 for MCF-7, 3.4 ± 0.19/1.54 for HeLa), a drug used for cancer chemotherapy. The structures of the newly synthesized hybrid compounds were identified by ¹H-NMR, ¹³C-NMR (APT), and elemental analysis data. These hybrid compounds represent a promising class of anticancer agents. Several compounds demonstrated marked and concentration-dependent cytotoxicity across all cancer cell lines, with HeLa cells showing the highest overall sensitivity. The introduction of an oxadiazole ring (compound 7) and coumarin substituents (compounds 12b–12d) markedly improved anticancer activity and selectivity, yielding low-micromolar IC₅₀ values in HeLa cells (10.6–13.6 µM) and high Selectivity Indexes (SI = 2.0–3.63). Compound 6 also exhibited balanced potency across A549, MCF-7, and HeLa cells (IC₅₀ = 28.3–31.2 µM) with SI values ≥ 2.0. Compound 9 showed strong cytotoxicity across all cancer cell lines; its moderate SI values indicate lower discrimination between malignant and non-malignant cells. Taken together, these findings identified compounds 7, 12b–12d, 6, and 12c as the most promising benzimidazolone-based candidates, displaying both potent cytotoxicity and favorable selectivity over non-malignant HEK293 cells. Conclusions: Among the synthesized molecules, the oxadiazole derivative (7) and the coumarin-based hybrids (12b–12d) exhibited the strongest combination of cytotoxic activity and selectivity, reflected by their low IC₅₀ values and high SI ratios. Notably, compound 12c combined strong biological activity with the highest predicted VEGFR2 affinity in the series, highlighting it as a particularly promising scaffold. While compound 9 exhibited excellent docking scores toward both VEGFR2 and CDK4, its lower selectivity suggests a need for further structural refinement. Overall, the biological and computational findings converge to identify these benzimidazolone hybrids as credible lead candidates for future anticancer optimization. Full article

Objective: Identifying biomarkers that predict metastatic potential or guide treatment selection is critical for improving breast cancer (BC) management. Previously, we established the Mitotic Network Activity Index (MNAI) as a prognostic marker in BC. Here, we bioinformatically and experimentally evaluated MNAI as a biomarker for metastasis risk and therapeutic response. Methods: We used Kaplan–Meier and Cox proportional hazard regression analyses to assess the association between MNAI and distant metastasis-free survival (DMFS) across 14 published BC datasets. A total of 16 publicly available clinical trial datasets, including the I-SPY trials, were used to evaluate the predictive value of MNAI for treatment response. Additionally, wound-healing and transmembrane assays were conducted to determine the effects of PLK1, CHEK1, and BUB1 inhibition on BC cell migration and invasion. Results: High MNAI levels were strongly associated with shorter DMFS. Multivariate analysis further confirmed MNAI as an independent risk factor for DMFS, beyond estrogen receptor status and PAM50-based molecular subtypes. Functionally, pharmacologic disruption of the mitotic network using PLK1, CHEK1, or BUB1 inhibitors significantly reduced cell migration and invasion in MDA-MB-231 and BT-549 BC cell lines. Moreover, BC cells with high MNAI increased sensitivity to microtubule-targeting agents such as docetaxel, paclitaxel, and ixabepilone but increased resistance to tamoxifen, AKT1/2 inhibitors, and mTOR inhibitors. Consistent with these findings, analysis of 16 clinical trial cohorts revealed that patients with high MNAI achieved higher pathological complete response rates to taxane-containing and ixabepilone-based therapies. Conclusions: Our findings demonstrate the MNAI as a clinically actionable biomarker that can refine risk stratification and guide the selection of targeted or chemotherapy regimens, advancing precision medicine in BC management. Full article

Background: Ewing sarcoma (ES) is an aggressive malignancy and there is an unmet need for more effective treatment options for patients. Histone deacetylases (HDACs) have been shown to be involved in ES tumorigenesis and HDAC inhibitors have been investigated in the context of ES. Our objective for this study was to investigate the efficacy and mechanism of action of HDAC inhibition in vitro and in vivo in ES models, alone and in combination with standard of care therapies. Methods/Results: HDAC inhibitors were tested for in vitro efficacy against ES cell lines and romidepsin was found to be most effective. The mechanistic changes induced by romidepsin were investigated by Western blotting and proteins involved in cell cycle progression and DNA damage repair were found to be repressed. In vitro we identified that romidepsin synergizes with doxorubicin and etoposide and that it increases the efficacy of the standard of care combinations VDC/IE. Further, the combination treatments lead to an increase in caspase 3/7 cleavage, a decrease in DNA damage repair proteins, and an accumulation of DNA damage. In vivo, the combination of romidepsin and ifosfamide/etoposide (IE) leads to a significant decrease in tumor volume compared to that of IE alone. Conclusions: Our data indicates that romidepsin improves efficacy of chemotherapeutic agents in vitro and leads to a decreased tumor volume in vivo, suggesting that the addition of romidepsin may improve upfront treatment in ES patients. Full article

Multidrug resistance (MDR) remains a major obstacle in the treatment of ovarian cancer. MDR is often mediated by the overexpression of ATP-binding cassette (ABC) transporters, such as P-glycoprotein (P-gp) and Breast Cancer Resistance Protein (BCRP). In this study, we evaluated the ability of elacridar, a dual P-gp and BCRP inhibitor, to overcome MDR in W1, an ovarian cancer cell line sensitive to Paclitaxel (PAC) and its PAC-resistant variants. Cells were cultured under both two-dimensional (2D) and three-dimensional (3D) conditions to account for differences in tumor-like microenvironments. The MDR1 gene and P-gp protein expression were determined for the analyzed model; P-gp activity was measured by flow-cytometry and fluorescent observation, with and without elacridar. The MTT tests were carried out to evaluate how elacridar, combined with chemotherapeutics, affects cell viability. Our results demonstrate that elacridar effectively inhibited transporter activity and increased cellular sensitivity to PAC and DOX. The inhibitory effect was observed in both 2D and 3D cultures, although the re-sensitization effect in 3D conditions was less pronounced, reflecting the complexity of tumor-specific resistance mechanisms. These findings highlight elacridar as a promising compound for reversing MDR in ovarian cancer and emphasize the importance of 3D models in preclinical drug evaluation. Further studies in advanced in vitro and in vivo models are required to assess the potential of elacridar better. Full article

Carborane is considered a three-dimensional mimetic of phenyl rings in medicinal chemistry. BMS-202 is a potent PD-L1 inhibitor that can block the PD-L1/PD-1 interaction and restore the immune response to cancer cells. Herein, we replaced the terminal phenyl group of BMS-202 with carborane and prepared its carboranyl BMS-202 analogues. The results showed a loss of PD-L1 binding affinity due to the bulky size of carborane, suggesting that carborane cannot serve as a phenyl ring mimetic in certain cases. Docking study demonstrated that the narrow binding pocket of PD-L1 could not hold the bulky carborane, resulting in loss of its activity. Compounds 1a and 1b exhibited anti-proliferative activities on a broad scope of cancer cell lines. Further studies indicate that compound 1a can induce cell apoptosis and lead to G1 cell cycle phase arrest. The boron biodistribution study of compound 1a revealed that the brain/blood uptake ratio was 0.60 ± 0.08, exhibiting a good blood-brain penetration capability. Full article

Histone deacetylases (HDACs) are pivotal epigenetic regulators that control gene expression, cell proliferation, and differentiation, and their dysregulation is closely associated with the onset and progression of multiple cancers. The therapeutic importance of these enzymes is reflected by FDA approval of HDAC inhibitors for oncology indications. Despite this clinical success, most FDA-approved agents employ conventional zinc-binding groups (ZBGs) such as hydroxamic acid and 2-aminoanilide, which are frequently linked to metabolic instability, genotoxicity, and poor pharmacokinetic behavior. These limitations have spurred the development of structurally diverse and safer HDAC inhibitors incorporating alternative ZBGs. This review provides a comprehensive analysis of recently developed HDAC inhibitors reported in the last few years, emphasizing their structure–activity relationships (SARs), chemical scaffolds, and binding features—including cap, linker, and ZBG motifs. Both hydroxamate-based and non-hydroxamate inhibitors, such as benzamides, hydrazides, and thiol-containing analogs, are critically evaluated. Moreover, the potency and selectivity profiles of these inhibitors are summarized across different cancer and normal cell lines, as well as specific HDAC isoforms, providing a clearer understanding of their therapeutic potential. Emerging dual-target HDAC inhibitors, such as HDAC–tubulin, HDAC–PI3K and HDAC–CDK hybrids, are also discussed for their synergistic anticancer effects. Full article

M2-like tumor-associated macrophages (TAMs) are a promising target for cancer immunotherapy, particularly for cancer patients who are refractory to current immune checkpoint inhibitors (ICIs). Previously, we showed that prostaglandin E1 (PGE1) enhances the expression of M1 markers, including HLA-DR, on macrophages and induces the M1 polarization of TAMs in vivo. This study investigated the pharmacological mechanisms by which PGE1 and its derivatives suppress the expression of M2 markers, including TREM2 and CXCR2. Macrophages were cultured in ultralow attachment dishes either alone or in combination with liver cancer cell lines to generate homospheroids or heterospheroids. Cell surface marker expression was assessed by flow cytometry. Compared with homospheroids, M2 marker expression on macrophages in heterospheroids was significantly increased, suggesting that heterospheroid culture promotes M2 polarization. PGE1 decreased M2 marker expression in heterospheroids more effectively compared with PGE2, PGE3, misoprostol, and 13,14-dihydro-15-keto-PGE1, whereas the suppressive effects of 15-keto- and 13,14-dihydro-PGE1s, and lubiprostone were comparable to that of PGE1. Pharmacological inhibition of prostaglandin receptors revealed that EP2 and EP4 receptors are involved in the PGE1-induced reprogramming of M2-like macrophages to M1 macrophages. In summary, PGE1 and its derivatives are promising TAM-targeting immunotherapeutics. Full article

Background: Glioblastoma (GBM) is an aggressive and treatment-resistant brain tumor with few effective therapies. Tubulin polymers are crucial for maintaining cell–cell signaling, cell proliferation, and cell division. Therefore, tubulin has been targeted by medicinal chemists to develop novel therapeutics to treat cancer. In this regard, we developed novel small-molecule tubulin inhibitors as potential therapeutics to treat GBM. Methods: We synthesized a focused library of pyrimidine-containing dihydroquinoxalinone-based analogs and tested nine compounds for cytotoxicity in GBM cell lines using the Sulforhodamine B (SRB) cell viability assay. We identified compound 8c as the most promising compound and evaluated the in vitro effects of 8c on GBM cell growth using live cell imaging and assessed apoptosis using a cell death ELISA. We then tested its anticancer activity in vivo on GBM xenografts grown in immunocompromised mice. Results: Several compounds demonstrated nanomolar IC₅₀ values in cell viability assays and outperformed temozolomide (TMZ), the current standard treatment for GBM patients. We identified compound 8c, which is a pyrimidine analog with a secondary amine, as the lead candidate for GBM studies in vitro and in vivo. Compound 8c reduced cell viability in a dose-dependent manner and induced complete growth arrest within 48 h at 3–10 nM concentrations in GBM cell lines. ELISA confirmed that compound 8c triggered dose-dependent apoptosis, whereas TMZ failed to induce apoptosis at nM concentrations. In vivo, compound 8c significantly inhibited GBM xenograft growth in immunocompromised mice by 66%. Conclusions: The potent tubulin inhibitor compound 8c has strong anti-GBM activity in vitro and in vivo and merits further preclinical development. Full article

The limited efficacy of cytotoxic chemotherapy in the context of gastric cancer treatment is largely driven by profound molecular and biological heterogeneity. In contrast, the development of antibody-mediated therapies has ushered in a new era of precision oncology by enabling selective molecular targeting and immune modulation. This review includes a comprehensive overview of the evolution of antibody-based therapeutics in gastric cancer, highlighting early breakthroughs, subsequent setbacks, and recent advances that have reshaped the treatment landscape. We summarize the current standard regimens targeting HER2, VEGFR2, PD-1/PD-L1, and CLDN18.2 and examine pivotal clinical trials evaluating monoclonal antibodies directed against these pathways. We also discuss emerging therapeutic modalities, including next-generation antibody–drug conjugates (ADCs), bispecific antibodies, and chimeric antigen receptor (CAR) T-cell therapies. Trastuzumab first established HER2-targeted therapy in gastric cancer, but the failure of trastuzumab emtansine (T-DM1) led to a decade-long stagnation until the advent of trastuzumab deruxtecan (T-DXd), which demonstrated robust clinical activity and defined a new standard of care. While bevacizumab failed to improve survival, the anti-VEGFR2 antibody ramucirumab emerged as an effective second-line therapy. Immune checkpoint inhibitors, including nivolumab and pembrolizumab, have been incorporated into first-line treatment for PD-L1-positive disease based on landmark trials such as CheckMate 649 and KEYNOTE-811. More recently, the CLDN18.2-targeted antibody zolbetuximab has expanded therapeutic options for biomarker-selected patients. Concurrently, a diverse pipeline of immune-based strategies—such as TROP2-directed ADCs, bispecific antibodies, and CAR-T cell therapies—is undergoing active clinical development. Together, advances in biomarker-driven antibody therapeutics are accelerating personalized cancer care and improving clinical outcomes in patients with gastric cancer. Full article

Background: Metastatic colorectal cancer (mCRC) with TP53 gene mutations, which are commonly found in tumors that are microsatellite stable (MSS) and not prone to genetic errors seen in some cancers, is associated with aggressive cancer behavior and poor outcomes. While MSI-high (MSI-H, referring to high levels of gene instability) disease benefits markedly from PD-1-based immunotherapy (drugs that inhibit the PD-1 protein on immune cells), TP53-mutated MSS tumors rarely receive immune checkpoint inhibitors (ICIs, drugs that help immune cells attack cancer) outside of trials and often only in later lines of therapy. Objective: We aimed to synthesize translational and clinical evidence regarding the effects of early rationale-driven immunotherapy combinations on survival outcomes, in TP53-mutated metastatic colorectal cancer, with a focus on practical clinical implications. Methods: This narrative review was conducted in accordance with SANRA criteria. Literature searches were performed in PubMed/MEDLINE, Scopus, and Web of Science (2010–2025). Relevant ESMO and NCCN guidelines and key references were also reviewed. Results: In KEYNOTE-177 study (MSI-H/dMMR), pembrolizumab improved PFS (HR 0.60) and showed durable OS with >5-year follow-up. CheckMate-142 reported sustained activity with nivolumab ± ipilimumab. Preclinical/early clinical data in MSS/TP53 suggest that ICIs may become effective when combined with priming (chemo/DDR) and vascular normalization (anti-VEGF), particularly in subsets with elevated TMB. The randomized ROME trial supports the clinical utility of genomically matched, NGS-guided strategies. Conclusions: A precision approach integrating TP53 status, TMB, and TME modulation could extend the immunotherapy benefit beyond MSI-H to TP53-mutated MSS mCRC; prospective first-line trials are warranted. Full article