Targeting FN1 to overcome gemcitabine resistance in gallbladder cancer: Mechanistic insights and an iRGD-modified PEG-PLGA nanoparticle delivery strategy.

Targeting the DDX3/PAF1 axis enhances chemotherapy efficacy in pancreatic ductal adenocarcinoma.

Pancreatic cancer presents significant imaging challenges due to its poor vascularization, while the hypoxic tumor microenvironment further contributes to chemoresistance. To address these limitations, we engineered exosome-ultrasmall iron oxide (Exo-USIO), a targeted exosomal nanoprobe encapsulating USIO nanoparticles (USIO NPs), designed to enable precise tumor imaging and enhance chemotherapy efficacy in pancreatic cancer. Exosomes derived from Panc-02 pancreatic cancer cells were isolated and loaded with USIO NPs via electroporation to synthesize Exo-USIO. The nanoprobe's targeting specificity, MRI contrast enhancement, and catalase-like activity (converting H2O2 to O2) were systematically evaluated. In vitro assays assessed cellular uptake, hypoxia modulation, and chemosensitivity, while in vivo studies validated tumor-targeted MRI imaging, hypoxia alleviation, and synergistic therapeutic effects with gemcitabine (GEM). Exo-USIO demonstrated a 2.3-fold increase in T1-weighted MRI signal intensity compared to free USIO NPs (P < 0.01), alongside efficient enzymatic conversion of H2O2 to O2, significantly reducing HIF-1α expression (P < 0.05). Combined with GEM, Exo-USIO reduced tumor cell viability to 39.8% in vitro and suppressed tumor growth by 62% in vivo (P < 0.001). Biosafety evaluations revealed negligible systemic toxicity or metastatic risk. By leveraging exosome-mediated targeted delivery and the dual enzyme-mimetic activity of USIO NPs, Exo-USIO achieves dual functionality: enhanced MRI-guided tumor localization and catalytic alleviation of hypoxia to reverse chemoresistance. This strategy overcomes key limitations of the pancreatic tumor microenvironment, offering a translatable platform for precision theranostics.

TPS904 Background: High-risk non-muscle-invasive bladder cancer (HR-NMIBC) unresponsive to adequate Bacillus Calmette-Guérin (BCG) has a high risk of recurrence and progression. Although several novel bladder-preserving approaches such as immune checkpoint inhibitors, viral gene therapy, and cytokine-based regimens, are under investigation, their efficacy remains limited, financial toxicity is a concern, and current FDA approvals are restricted to carcinoma in situ (CIS). Radical cystectomy (RC) therefore remains the standard of care, but many patients are ineligible or decline surgery. Both intravesical mitomycin-C (MMC) and gemcitabine (GEM) have demonstrated efficacy in NMIBC, and sequential administration may offer synergistic benefit. No prospective data exist. Methods: The IMGeS study is an investigator-initiated, prospective, open-label, multicentre, single-arm phase II trial evaluating the efficacy and safety of sequential intravesical MMC and GEM in BCG-unresponsive HR-NMIBC. Eighty-two patients will be enrolled from eight Korean centres over 24 months, with 12 months of follow-up. Eligible patients have histologically confirmed BCG-unresponsive high-risk NMIBC per AUA criteria, including refractory or relapsing disease within 6–9 months of adequate BCG, and are unsuitable for or refuse RC. Key exclusions include muscle-invasive or metastatic disease, upper tract urothelial carcinoma, prior intravesical MMC or GEM within 2 years (except a single immediate postop dose), and other predominant histology. Following TURBT, patients receive induction with MMC 40 mg/20 mL intravesically retained for 1–2 hours, immediately followed by gemcitabine 2 g/50 mL retained for 1–2 hours, weekly for 6 weeks. Patients without recurrence at 3-month cystoscopy receive monthly maintenance instillations for 12 months. The primary endpoint is 1-year high-risk recurrence-free survival (HRFS); secondary endpoints include progression-free, cystectomy-free, cancer-specific, and overall survival, as well as safety and tolerability. Exploratory endpoints include biomarker analyses from tumor, urine, and blood. Clinical trial information: NCT06388720 .

Integrated pharmacokinetic properties, tissue distribution and metabolism of multiple active constituents in DBD for the treatment of GEM-induced myelosuppression.

Linc01833 drives gemcitabine resistance in non-small cell lung cancer by shielding SLC7A11 from WWP1-mediated ubiquitination and inhibiting ferroptosis.

Biodegradable polymersomes encapsulating copper peroxide and gemcitabine for targeted chemoimmunotherapy.

Pancreatic cancer, one of the most malignant solid tumors with the poorest prognosis, is commonly treated with gemcitabine (GEM)-based systemic chemotherapy. However, chemoresistance remains a significant therapeutic challenge. Ferroptosis, a novel form of programmed cell death, has demonstrated exceptional susceptibility in chemoresistant cancer cells. Due to their unique magnetic responsiveness, iron oxide nanoparticles can generate heat under alternating magnetic fields, which enables magnetic hyperthermia (MH) therapy. This approach not only directly induces tumor cell apoptosis but also enhances chemosensitization. In this study, we demonstrate that ferrimagnetic vortex-domain iron oxide nanorings (FVIOs) as an ideal nanoplatform for MH, significantly improving GEM chemosensitivity in pancreatic cancer. Both in vitro and in vivo experiments demonstrated that MH not only synergizes with GEM to exhibit an antitumor effect in wild-type (WT) pancreatic tumors, but also directly suppresses the proliferation of gemcitabine-resistant (GR) counterparts while alleviating chemoresistance. High-throughput transcriptomic profiling revealed an increased susceptibility of GR cells to ferroptosis induction. Mechanistically, MH suppressed HSPB1 expression in GR cells, thereby attenuating its regulatory role in the ubiquitination-mediated degradation of ACSL4 protein and ultimately promoting ferroptosis. Comprehensive in vivo evaluations confirmed the multidimensional chemosensitizing efficacy of MH alongside favorable biosafety. Our findings highlight MH as a promising adjuvant strategy for pancreatic cancer, particularly in GEM-resistant cases, by overcoming chemoresistance through the potentiation of ferroptosis.

Background: Colorectal and pancreatic cancers remain therapeutically challenging, with limitations in efficacy and limitations due to toxicity from conventional antimetabolites such as 5-fluorouracil (5-FU), methotrexate (MTX), and gemcitabine (GEM). Steroidal conjugation offers an approach to enhance selectivity and toxicokinetics. Methods: Five novel hybrid homo-aza (lactam) steroidal antimetabolites (GE23, CS18, CS23, KA44, MV16) were synthesized and tested against three pancreatic and four colorectal carcinoma cell lines with distinct molecular characteristics. Antiproliferative activity (MTT), apoptosis (Annexin V/PI), and cell cycle effects were assessed. Thymidylate synthase (TS) and dihydrofolate reductase (DHFR) inhibition was examined via molecular docking, Western blot, and enzymatic assays. Correlations between docking binding scores (DBS) and biological data were analyzed, and effects were compared with reference drugs (5-FU, MTX, GEM). Results: CS23, CS18, and KA44 exhibited the most potent cytostatic activity (mean GI50 10-80 µM). CS23 also induced high cytocidal effects, strong apoptosis (40% at 72 h), and G1/S arrest. Moreover, docking predicted the high binding affinity of CS23 for both TS (-11.2 kcal/mol) and DHFR (-11.5 kcal/mol), which was validated by Western blot and enzymatic inhibition (IC50 ≈ 20 nM). Correlation analyses showed significant relationships between hybrid steroidal antimetabolites' cytostatic efficacy and DBS for TS (r = -0.75) and DHFR (r = -0.76), and combined DBS values predicted growth inhibition (r = -0.81, p < 0.01). No simple, universal correlation with single mutations of KRAS, BRAF, PI3K, or TP53 was found. Conclusions: Lactam steroidal antimetabolite hybrids, particularly CS23, act as dual TS/DHFR inhibitors, inducing apoptosis and cell cycle arrest with improved selectivity. Their strong in silico-in vitro concordance provides a compelling preclinical rationale for further evaluation of steroidal antimetabolites as next-generation therapeutics for resistant gastrointestinal malignancies.

Glioblastoma (GBM) is one of the most aggressive malignancies of the central nervous system. Gemcitabine (GEM), a pyrimidine analogue with broad-spectrum anticancer activity, can activate the cGAS-STING pathway and alleviate the immunosuppressive microenvironment of GBM. However, its clinical application is hampered by the formidable challenge of crossing the blood-brain barrier (BBB) and accumulating at the tumor lesion. Herein, a dual-responsive biomimetic nanoprodrug (RMM@GEM NPs) was exploited to enhance the efficient BBB penetration and target cargo delivery by functionalization of glioblastoma cell membranes (MM) camouflaging and further targeting peptide RAP modification. After its selective accumulation at glioma lesion, RMM@GEM NPs accelerates GEM release under the tumor pathological stimuli of reactive oxygen species (ROS) and acidic microenvironment to robustly activate the STING signaling cascades (increased p-STING, p-TBK1, p-IRF3, and p-NF-κB). Simultaneously, cyclodextrin-mediated cholesterol depletion further suppresses PD-L1 expression and alleviates T-cell exhaustion. These findings highlight RMM@GEM NPs as a promising strategy to enhance immune responses in “cold” tumor, providing a potential candidate for efficient and safe immunotherapy in GBM.Graphical Supplementary InformationThe online version contains supplementary material available at 10.1186/s12951-026-04055-4.

Chemotherapy-induced immunosuppression compromises therapeutic outcomes in oncology, particularly in non-small cell lung cancer (NSCLC). While natural polysaccharides have emerged as promising candidates to counteract drug-related immunosuppression, the therapeutic potential of riclin remains unexplored in chemotherapeutic contexts. Here, we systematically evaluated riclin's immunoadjuvant efficacy in a murine NSCLC model treated with gemcitabine (GEM). Oral riclin modulated gut microbiota diversity and metabolite profiles while activating the immune-hematopoietic axis, thereby boosting immunity and hematopoiesis. Mechanistically, riclin counteracted GEM-induced immunosuppression through coordinated NF-κB and JAK-STAT activation, as evidenced by the restoration of circulating immune cells and splenic architecture, expansion of bone marrow mononuclear cells (BMNCs) and Lineage⁻Sca-1⁺Kit⁺ (LSK) cells, and suppression of apoptosis. Notably, riclin demonstrated synergistic effects with GEM, achieving 98% tumor burden reduction while concurrently alleviating systemic immunosuppression. We propose that riclin, a novel oral immunoadjuvant capable of enhancing chemotherapeutic efficacy in NSCLC, supports its clinical development as a promising combination strategy.

Pro-inflammatory and pro-thrombotic stimuli can activate endothelial cells (ECs) and predispose them to thrombotic microangiopathies (TMAs). Drug-induced TMA (DITMA) may occur in clinical practice during treatment with interferon-β1a (IFN-β1a), ciclosporin A (CsA), and gemcitabine (GEM). DITMA may also trigger the complement system and induce membrane attack complex (MAC, C5b-9) deposition in vivo, although their role and the benefit of inhibition remain unclear. In an experimental in vitro model of microvascular ECs exposed to these three drugs, we searched for MAC deposits and drug-specific pro-inflammatory and pro-thrombotic traits to gain insights into the mechanisms potentially involved in DITMA. Human microvascular endothelial cells line-1 (HMEC-1) was treated with 10% normal human serum, CsA, GEM, and IFN-β1a. Cell viability for each drug was measured using the resazurin assay. Cell component expression of the following markers involved in endothelial pathogenic activation was measured via immunofluorescence and flow cytometry: C5b-9, interleukin (IL)-1α, IL-6, E-selectin, platelet EC adhesion molecule-1 (PECAM-1), intercellular adhesion molecule-1 (ICAM-1), and von Willebrand factor (vWF). Levels of plasminogen activator inhibitor-1 (PAI-1) and urokinase plasminogen activator (uPA) were measured in the supernatants using the enzyme-linked immunosorbent assay (ELISA). Significantly increased C5b-9 deposits were found with each drug, and increased drug-specific activation marker expressions appeared in HMEC-1s when exposed to CsA (IL-1α, IL-6, ICAM-1, E-selectin, vWF, and uPA), GEM (IL-1α, IL-6, PECAM-1, ICAM-1, E-selectin, and vWF), and IFN-β1a (PECAM-1, ICAM-1, PAI-1, and uPA). Each drug induces MAC deposits on HMEC-1s and singular endothelial activation profiles, potentially leading to thrombogenesis observed in DITMA.

Tumor hypoxia promotes angiogenesis, dysfunctional vascular formation, and the epithelial-to-mesenchymal transition phenotype. We propose that a CXCR4 inhibitor (AMD3100) could decrease cancer stemness and improve the efficacy of the anticancer drug gemcitabine (GEM) in targeting hypoxic pancreatic ductal adenocarcinoma (PDAC) cells. In this study, we synthesized a hypoxia-responsive polymer containing poly(lactic acid)-diazobenzene-poly(ethylene glycol) to produce hypoxia-responsive polymersomes. Cell viability experiments showed that AMD3100 enhanced the cytotoxicity of GEM-encapsulated polymersomes under hypoxic conditions compared to normoxia. The combined treatment significantly elevated pro-apoptotic BAX mRNA levels and reduced antiapoptotic BCL2 mRNA levels. Additionally, the combination therapy decreased the size of cancer cell spheroids from PANC1 and patient-derived cells.

Sustained and localized delivery of gemcitabine using chitosan-PVA-TPP polymeric implant enhances antitumor efficacy and delays surgical relapse in pancreatic cancer.

Trimodal therapy (TMT) is a viable option for muscle-invasive bladder cancer (MIBC), but the optimal chemotherapy regimen remains unclear. This phase II randomized trial (NCT01495676) compared cisplatin (CDDP) with twice-weekly gemcitabine (GEM) and radiation therapy (RT) with CDDP plus RT. Patients with pT2-pT3N0M0 MIBC, after macroscopically complete transurethral resection (TURBT), received RT (63Gy to the bladder, 45Gy to the pelvis, 1,8 Gy/ fraction) with chemotherapy (CDDP 20mg/m2/day for 4days every 21days alone or plus GEM 25mg/m2 twice weekly). The primary endpoint was 2-year disease-free survival (DFS); secondary endpoints included overall survival (OS) and toxicities. A 1:2 randomization was planned to include 36 patients in the control arm and 73 patients in the experimental arm. Sixty-nine patients were included: 24 in the RT/CDDP arm and 45 in the RT/CDDP/GEM arm. The median follow-up was 63months. Two-year DFS was similar between groups (58.3% CI95% [36.6-77.9] vs. 60.0% CI95% [44.3-74.3]), with median DFS of 29.8 (RT/CDDP) vs. 37.4 (RT/CDDP/GEM) months. OS at 24 and 60months was 91.3% [IC 95% 69.5-97.8] and 66.8% [IC 95% 39.6-83.9] (RT/CDDP) vs. 66.7% % [IC 95% 50.2 - 78.8] and 53.7% [IC 95% 37.2 - 67.6] (RT/CDDP/GEM). Toxicity profiles were comparable except for increased cytopenias in the GEM arm. Adding GEM to CDDP did not improve 2-year DFS in MIBC patients treated with TMT. Results should be interpreted cautiously due to early study termination and insufficient accrual.

Background: Pancreatic cancer (PaCa) has an extremely poor prognosis. This malignancy rapidly acquires resistance to gemcitabine (GEM), a key chemotherapeutic agent, yet the mechanisms underlying this resistance remain incompletely understood. We previously established GEM-resistant (GEM-R) PaCa cell lines and found that these cells exhibit constitutively increased levels of matrix metalloproteinase-1 (MMP-1), which contributes to the invasion and metastasis of PaCa. Kaempferol, a naturally occurring flavonoid found in many plant species, has been shown to exhibit antitumor effects across a range of cancers. Methods/Results: This study demonstrated that non-cytotoxic concentrations of kaempferol significantly decrease MMP-1 protein expression in GEM-R PaCa and suppress their migration and invasion capacities. Western blot analysis demonstrated that MMP-1 protein levels were upregulated in GEM-R PaCa cells and decreased upon kaempferol exposure. In Transwell migration/invasion and wound healing assays, GEM-R PaCa cell lines exhibited enhanced migration and invasion capacities compared with GEM-S cells, whereas kaempferol treatment suppressed these properties, similar to the effects observed by MMP-1 knockdown or treatment with the MMP inhibitor batimastat. Furthermore, kaempferol treatment reduced phosphorylated Akt expression and NF-κB p65 activity. Conclusions: These findings indicate that kaempferol suppresses the migratory and invasive abilities of PaCa cells by downregulating MMP-1 through negative regulation of the Akt and NF-κB signaling cascades, while kaempferol holds promise as a treatment strategy for GEM-R PaCa.

Pancreatic cancer remains a highly lethal disease, underscoring the continued importance of chemotherapy. The first-line chemotherapeutic agent Gemcitabine (GEM) exerts its effect by inducing tumor cell apoptosis, a process which can subsequently convert to pyroptosis via GSDME expression. Nevertheless, the emergence of drug resistance has prompted extensive research to identify novel therapeutic targets. p21-activated kinase 4 (PAK4) plays important roles in various tumors, including the inhibition of tumor cell apoptosis. Here, we show that PAK4 inhibits pyroptosis in pancreatic cancer through the NAcht leucinerich-repeat protein-1 (NLRP1)/caspase-9/caspase-3/GSDME axis. PAK4 phosphorylates the E3 ubiquitin ligase mouse double minute 2 homolog (Mdm2) to promote the degradation of NLRP1, thereby inhibiting pyroptosis. Furthermore, inhibition of PAK4 kinase activity promotes GEM-induced suppression of pancreatic cancer growth both in vitro and in vivo. Our study suggests that targeting PAK4 to promote GEM-induced pyroptosis may provide a new therapeutic approach for the treatment of pancreatic cancer.

Triptolide (TP) exhibits various pharmacological activities. Our previous studies have confirmed the efficacy of TP against lung adenocarcinoma (LUAD). However, the potent pharmacological activity of TP is underpinned by its complex mechanisms. Exploring its potential mechanisms is of great value for promoting the clinical application of TP and extending its clinical use. Differentially expressed genes (DEGs) associated with LUAD were analyzed and acquired from the TCGA database, while DEGs related to TP were obtained through RNA sequencing. Hub genes were identified through LASSO and random forest models. The efficacy of TP against LUAD was validated using tumor-bearing mouse models and A549 cells. The validation of hub genes was conducted using RT-qPCR. The regulatory effect of hub genes on TP efficacy was validated through overexpression cell models. Furthermore, the potential mechanisms by which TP improves gemcitabine (GEM) resistance were explored using a GEM-resistant cell line in combination with the overexpression model. This study validated the therapeutic effect of TP against LUAD invivo and invitro. Bioinformatics revealed that the mechanism of TP's effect against LUAD might be associated with amino acid-related biological processes. Five hub genes were screened and identified by combining bioinformatics methods and experiments. The overexpression model validated that PSAT1 plays an effective role in the efficacy of TP and in alleviating GEM resistance. This study preliminarily demonstrated that the anti-LUAD effect of TP was associated with the PSAT1-regulated serine biosynthesis pathway, and that TP effectively improves GEM resistance by inhibiting PSAT1 expression.

675 Background: Gemcitabine (GEM)-based neoadjuvant chemoradiotherapy is administered to facilitate curative resection in pancreatic ductal adenocarcinoma (PDAC). For recurrent PDAC after resection, gemcitabine plus nab-paclitaxel (GnP) therapy is often selected as first-line systemic therapy, resulting in repeated exposure to GEM-containing regimens. However, it is unclear how the response to prior GEM-based neoadjuvant therapy influences the efficacy of GnP for recurrence. This study aimed to evaluate whether tumor regression during neoadjuvant therapy correlates with GnP treatment outcomes in patients with recurrent PDAC. Methods: We retrospectively reviewed 51 patients with resectable and borderline resectable PDAC who received neoadjuvant GEM-based chemoradiotherapy, followed by curative-intent resection between April 2014 and March 2023, and who received subsequent first-line chemotherapy with GnP for recurrence. Patients were classified into a "high-regression group” (≥30% tumor reduction during neoadjuvant therapy, n = 32) or a "low-regression group” ( &lt; 30% reduction, n = 19) based on the response to the neoadjuvant chemoradiotherapy. Overall survival (OS) and progression free survival (PFS) was measured from the treatment initiation for recurrent PDAC. Results: At the time of initial diagnosis, the median age was 63 years (range, 46-78); 27 patients were men. 27 patients were resectable PDAC. All patients underwent neoadjuvant chemoradiation therapy, and chemotherapy regimens in 36 of these cases were GnP. After the neoadjuvant chemoradiotherapy, 30 patients underwent pancreaticoduodenectomy, 20 underwent distal pancreatectomy, and one underwent total pancreatectomy. R0 resection was achieved in 50 patients. After the surgery, adjuvant chemotherapy based on S-1 was administered to 45 patients. The most common sites of recurrence were the lung and liver in 17 patients each, followed by local recurrence in 16 patients (including duplicates). The median follow-up after initiation of GnP therapy was 17.9 months. Patients in the high-regression group demonstrated a significantly longer median PFS compared to the low-regression group (11.8 months vs. 5.8 months, p = 0.010). Similarly, the objective response rate (ORR) was significantly higher in the high-regression group (43.8% vs. 10.5%, p = 0.015). However, there was no significant difference in median OS between the two groups (19.9 months vs. 18.6 months, respectively; p = 0.784). Conclusions: Patients with greater tumor regression during GEM-based neoadjuvant chemoradiotherapy had better PFS and ORR to GnP therapy after recurrence. These findings may suggest the importance of tumor response to neoadjuvant therapy as a potential predictor of chemosensitivity and support its use as a guide for subsequent treatment strategies for recurrent PDAC.

BackgroundThe recurrence rate remains high in patients with intermediate- and high-risk non-muscle-invasive bladder cancer (NMIBC), and some patients may experience disease progression despite curative trans-urethral resection and adjuvant therapy.ObjectiveTo compare the outcomes of intermediate- and high-risk NMIBC patients treated with Bacillus Calmette–Guerin (BCG) versus hyperthermic intravesical chemotherapy (HIVEC) with gemcitabine (GEM).MethodsA retrospective analysis of our single-institutional, prospectively collected database from July 2018 to February 2020 was performed. Patients with intermediate- and high-risk NMIBC and treated with HIVEC/GEM or BCG were selected. The two adjuvant therapies were compared in terms of recurrence-free survival (RFS), progress-free survival (PFS), and cancer-specific survival (CSS) at 24 months. Adverse events were also assessed and compared between groups.ResultsA total of 85 patients (38 in the HIVEC/GEM group and 47 in the BCG group) were included in the study. Patients’ characteristics were comparable between groups. There were no statistically significant differences in RFS (78.0% for HIVEC/GEM versus 75.0% for BCG, p = 0.592), PFS (91.7% for HIVEC/GEM versus 94.6% for BCG, p = 0.670), and CSS at 24 months. AEs were less common with HIVEC/GEM treatment than BCG (47.37% (18/38) versus 70.20% (33/47), p = 0.033). Most AEs were mild with CTCAE grade 1-2 (42.1% (16/38) for HIVEC/GEM and 63.8% (30/47) for BCG, p = 0.046).ConclusionsAmong patients with intermediate- and high-risk NMIBC, hyperthermic intravesical chemotherapy combined with gemcitabine, compared with BCG treatment, significantly reduced the adverse events rate without compromising oncological survival outcomes. The primary limitations of this study are its small sample size and retrospective nature.