Revealing the impact of modified modules flexibility on gemcitabine prodrug nanoassemblies for effective cancer therapy.

Prodrug nanoassemblies combine the advantages of prodrug strategies and nanotechnology have been widely utilized for delivering antitumor drugs. These prodrugs typically comprise active drug modules, response modules, and modification modules. Among them, the modification modules play a critical factor in improving the self-assembly ability of the parent drug. However, the impact of the specific structure of the modification modules on prodrug self-assembly remains elusive. In this study, two gemcitabine (GEM) prodrugs are developed using 2-octyl-1-dodecanol (OD) as flexible modification modules and cholesterol (CLS) as rigid modification modules. Interestingly, the differences in the chemical structure of modification modules significantly affect the assembly performance, drug release, cytotoxicity, tumor accumulation, and antitumor efficacy of prodrug nanoassemblies. It is noteworthy that the prodrug nanoassemblies constructed with flexible modifying chains (OD) exhibit improved stability, faster drug release, and enhanced antitumor effects. Our findings elucidate the significant impact of modification modules on the construction of prodrug nanoassemblies.

Human bone marrow mesenchymal stem cell-derived exosomes loaded with gemcitabine inhibit pancreatic cancer cell proliferation by enhancing apoptosis.

BACKGROUND: Pancreatic cancer remains one of the most lethal malignancies, and has limited effective treatment. Gemcitabine (GEM), a chemotherapeutic agent, is commonly used for clinical treatment of pancreatic cancer, but it has characteristics of low drug delivery efficiency and significant side effects. The study tested the hypothesis that human bone marrow mesenchymal stem cell (MSC)-derived exosomes loaded with GEM (Exo-GEM) would have a higher cytotoxicity against human pancreatic cancer cells by enhancing their apoptosis. AIM: To investigate the cytotoxicity of MSC-derived Exo-GEM against pancreatic cancer cells in vitro. METHODS: Exosomes were isolated from MSCs and characterized by transmission electron microscopy and nanoparticle tracking analysis. Exo-GEM through electroporation, sonication, or incubation, and the loading efficiency was evaluated. The cytotoxicity of Exo-GEM or GEM alone against human pancreatic cancer Panc-1 and MiaPaca-2 cells was assessed by MTT and flow cytometry assays. RESULTS: The isolated exosomes had an average size of 76.7 nm. The encapsulation efficacy and loading efficiency of GEM by electroporation and sonication were similar and significantly better than incubation. The cytotoxicity of Exo-GEM against pancreatic cancer cells was stronger than free GEM and treatment with 0.02 µM Exo-GEM significantly reduced the viability of both Panc-1 and MiaPaca-2 cells. Moreover, Exo-GEM enhanced the frequency of GEM-induced apoptosis in both cell lines. CONCLUSION: Human bone marrow MSC-derived Exo-GEM have a potent cytotoxicity against human pancreatic cancer cells by enhancing their apoptosis, offering a promising drug delivery system for improving therapeutic outcomes.

Quantum Insights into Partially Molecular Imprinted Microspheres for Anticancer Therapeutics: Experimental and Theoretical Studies.

Drug solubility is a determining factor for controlled release, and solubility-dependent release kinetics can be modified by changing the drug's state in the polymer matrix through partial molecular imprinting (PMI), although research in this area remains limited. This novel PMI approach creates nanocavities within the polymer by partially retaining the imprinting molecule and trapping the drug. Such a method holds promise for developing advanced biomaterial-based drug delivery systems for anticancer therapies. In this study, we developed microspheres designed for anticancer drug delivery utilizing PMI to enhance controlled release properties. Poly(vinyl alcohol) (PVA) microspheres were partially imprinted with aspirin (ASP) to create nanocavities for gemcitabine (GEM) molecules, inducing a polymorphic shift of GEM within the polymer matrix. This novel PMI approach enhanced drug release properties by enabling control over the drug crystallinity and release rate. The PVA-ASP-GEM complex showed zero-order release kinetics, releasing 21.6% of GEM over 48 h, maintaining steady state release profile. In contrast, nonimprinted PVA-GEM microspheres exhibited first-order kinetics with a faster release of 46.85% in the same period. Quantum insights from density functional theory (DFT) calculations revealed the superior stability of the PVA-ASP-GEM complex, with a binding free energy of -56.03 kcal/mol, compared to -29.07 kcal/mol for PVA-GEM. Molecular dynamics (MD) simulations demonstrated that ASP's presence created nanocavities that restricted GEM's movement, further contributing to the controlled release. Experimental validation through differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and Raman spectroscopy confirmed the polymorphic transitions within the PVA-ASP-GEM complex. This PMI-based approach offers a promising method for modulating drug release kinetics and improving the stability of anticancer therapeutics, paving the way for innovative biomaterial-based drug delivery systems.

A randomized trial of pharmacological ascorbate, gemcitabine, and nab-paclitaxel for metastatic pancreatic cancer.

BACKGROUND: Patients with metastatic pancreatic ductal adenocarcinoma (PDAC) have poor 5-year survival. Pharmacological ascorbate (P-AscH-, high dose, intravenous, vitamin C) has shown promise as an adjunct to chemotherapy. We hypothesized adding P-AscH- to gemcitabine and nab-paclitaxel would increase survival in patients with metastatic PDAC. METHODS: Patients diagnosed with stage IV pancreatic cancer randomized 1:1 to gemcitabine and nab-paclitaxel only (SOC, control) or to SOC with concomitant P-AscH-, 75 g three times weekly (ASC, investigational). The primary outcome was overall survival with secondary objectives of determining progression-free survival and adverse event incidence. Quality of life and patient reported outcomes for common oncologic symptoms were captured as an exploratory objective. Thirty-six participants were randomized; of this 34 received their assigned study treatment. All analyses were based on data frozen on December 11, 2023. RESULTS: Intravenous P-AscH- increased serum ascorbate levels from micromolar to millimolar levels. P-AscH- added to the gemcitabine + nab-paclitaxel (ASC) increased overall survival to 16 months compared to 8.3 months with gemcitabine + nab-paclitaxel (SOC) (HR = 0.46; 90 % CI 0.23, 0.92; p = 0.030). Median progression free survival was 6.2 (ASC) vs. 3.9 months (SOC) (HR = 0.43; 90 % CI 0.20, 0.92; p = 0.029). Adding P-AscH- did not negatively impact quality of life or increase the frequency or severity of adverse events. CONCLUSIONS: P-AscH- infusions of 75 g three times weekly in patients with metastatic pancreatic cancer prolongs overall and progression free survival without detriment to quality of life or added toxicity (ClinicalTrials.gov number NCT02905578).

RNA Nanotechnology for Codelivering High-Payload Nucleoside Analogs to Cancer with a Synergetic Effect.

Nucleoside analogs are potent inhibitors for cancer treatment, but the main obstacles to their application in humans are their toxicity, nonspecificity, and lack of targeted delivery tools. Here, we report the use of RNA four-way junctions (4WJs) to deliver two nucleoside analogs, floxuridine (FUDR) and gemcitabine (GEM), with high payloads through routine and simple solid-state RNA synthesis and nanoparticle assembly. The design of RNA nanotechnology for the co-delivery of nucleoside analogs and the chemotherapeutic drug paclitaxel (PTX) resulted in synergistic effects and high efficacy in the treatment of Triple-Negative Breast Cancer (TNBC). The 4WJ-drug complexes were confirmed to have efficient tumor spontaneous targeting and no toxicity because the motility of RNA nanoparticles has been previously shown to enable these RNA-drug complexes to spontaneously accumulate in tumor blood vessels. The negative charge of RNA enables those RNA complexes that are not targeted to tumor vasculature to circulate in the blood and enter the urine through the kidney glomerulus, without accumulating in organs, therefore being nontoxic. Drug incorporation into RNA 4WJ can be precisely controlled with a defined loading amount, location, and ratio. The incorporation of nucleoside analogs into 4WJ only requires one step using nucleoside analogue phosphoramidites during solid-phase RNA synthesis, without the need for additional conjugation and purification processes.

Metal Complexation for the Rational Design of Gemcitabine Formulations in Cancer Therapy.

Nanoformulation of chemotherapies represents a promising strategy to enhance outcomes in cancer therapy. Gemcitabine is a chemotherapeutic agent approved by the Food and Drug Administration for the treatment of various solid tumors. Nevertheless, its therapeutic effectiveness is constrained by its poor metabolic stability and pharmacokinetic profile. Nanoformulations of gemcitabine in lipid and polymer nanocarriers usually lead to poor loading capability and an inability to effectively control its release profile due to the physicochemical characteristics of the drug and matrices. Here, we propose metal-gemcitabine complexation with biorelevant metal cations as a strategy to alter the properties of gemcitabine in a noncovalent manner, paving the way for the development of novel nanoformulations. A speciation study on gemcitabine and Mn2+, Zn2+, and Ca2+ was performed with the aim of investigating the extent of the interaction between the drug and the proposed metal cations, and selecting the best conditions of temperature, pH, and drug-to-metal molar ratio that optimize such interactions. Also, a series of density functional theory calculations and spin-polarized ab initio molecular dynamics simulations were carried out to achieve insights on the atomistic modalities of these interactions. Mn2+-gemcitabine species demonstrated the ability to maintain gemcitabine's biological activity in vitro. The scientific relevance of this study lies in its potential to propose metal-gemcitabine as a valuable strategy for developing nanoformulations with optimized quality target product profiles. The work is also clinically relevant because it will lead to improved treatment outcomes, including enhanced efficacy and pharmacokinetics, decreased toxicity, and new clinical possibilities for this potent therapeutic molecule.

Flurbiprofen inhibits cAMP transport by MRP4/ABCC4 increasing the potency of gemcitabine treatment in PDAC cell models.

Pancreatic ductal adenocarcinoma (PDAC) remains a highly malignant cancer with a grim prognosis due to its early metastasis and resistance to current chemotherapies, such as Gemcitabine (GEM). We have previously demonstrated that cAMP exclusion by MRP4 is critical for PDAC cell proliferation, establishing this transporter as a promising prognostic marker and therapeutic target. In search for novel therapeutic options to improve GEM efficacy, we conducted a drug repositioning screening to identify potential inhibitors of cAMP transport by MRP4. Several non-steroidal anti-inflammatory drugs (NSAIDs) can inhibit the transport of certain MRP4 substrates. In this study, we assessed the efficacy of sixteen NSAIDs in inhibiting cAMP transport mediated by MRP4, identifying seven potent inhibitors based on their IC50 values. The most potent inhibitors were further tested for their effect on cell proliferation and migration. Flurbiprofen emerged as the most potent inhibitor of both MRP4-mediated cAMP transport and cell proliferation. Overexpression of MRP4 in BxPC-3 cells significantly increased GEM resistance, and co-administration of flurbiprofen with GEM markedly enhanced the latter's potency inhibiting PDAC cells proliferation. These findings position flurbiprofen as a potent inhibitor of cAMP transport by MRP4 and a promising adjunctive therapy to enhance GEM effectiveness in PDAC treatment.

Exploring epigenetic dynamics unveils a super-enhancer-mediated NDRG1-ß-catenin axis in modulating gemcitabine resistance in pancreatic cancer.

Chemoresistance remains a formidable challenge in pancreatic ductal adenocarcinoma (PDAC) treatment, necessitating a comprehensive exploration of underlying molecular mechanisms. This work aims to investigate the dynamic epigenetic landscape during the development of gemcitabine resistance in PDAC, with a specific focus on super-enhancers and their regulatory effects. We employed well-established gemcitabine-resistant (Gem-R) PDAC cell lines to perform high-throughput analyses of the epigenome, enhancer connectome, and transcriptome. Our findings revealed notable alterations in the epigenetic landscape and genome architecture during the transition from gemcitabine-sensitive to -resistant PDAC cells. Remarkably, we observed substantial plasticity in the activation status of super-enhancers, with a considerable proportion of these cis-elements becoming deactivated in chemo-resistant cells. Furthermore, we pinpointed the NDRG1 super-enhancer (NDRG1-SE) as a crucial regulator in gemcitabine resistance among the loss-of-function super-enhancers. NDRG1-SE deactivation induced activation of WNT/ß-catenin signaling, thereby conferring gemcitabine resistance. This work underscores a NDRG1 super-enhancer deactivation-driven ß-catenin pathway activation as a crucial regulator in the acquisition of gemcitabine-resistance. These findings advance our understanding of PDAC biology and provide valuable insights for the development of effective therapeutic approaches against chemoresistance in this malignant disease.

A meta-analysis and systematic review of randomized controlled trials in combination gemcitabine with erlotinib in the pancreatic cancer.

BACKGROUND: Previous studies have demonstrated the efficacy and safety of combining gemcitabine and erlotinib (Gem-Erlo) for the treatment of pancreatic cancer (PaC). However, there is a limited number of clinical studies and multiple prospective randomized controlled trials (RCTs) have yielded inconsistent conclusions. The question of whether Gem-Erlo has significant advantages over conventional chemotherapy in the treatment of PaC has been controversial. In order to provide valuable insights for PaC treatment, this study conducted a meta-analysis based on the current evidence from RCTs. METHODS: We searched several databases including PubMed/Medline, Web of Science, Cochrane Library, and Embase, as well as relevant conference abstracts from the beginning of their inception to July 2023. We used the patient/population, intervention, comparison, outcomes and study design (PICOS) principle to screen the literature. After title, abstract and full text filtering, we extract the data from each study to assess the risk of bias by examining the quality of the literature. We used a meta-analysis with random effects model to synthesize and summarize the results regarding objective response rate (ORR), disease control rate (DCR), median progression-free survival (median PFS), median overall survival (median OS) and 1-year survival rate. RESULTS: Seven RCTs were included, involving 2,152 PaC patients treated with either Gem-Erlo or gemcitabine alone. The results showed that Gem-Erlo significantly improved DCR [odds ratio (OR) =1.74; 95% confidence interval (CI): 1.03 to 2.92; P=0.04]; but did not significantly improve median OS [standardized mean difference (SMD) =-0.20; 95% CI: -1.46 to 1.06; P=0.75], median PFS (SMD =-0.97; 95% CI: -4.01 to 2.07; P=0.53), ORR (OR =1.29; 95% CI: 0.84 to 1.97), or 1-year survival rate (OR =1.18; 95% CI: 0.88 to 1.57). In addition, sensitivity analysis of the median OS showed the Gem-Erlo group significantly prolonged the median OS compared to the gemcitabine alone group [weighted mean difference (WMD) =-1.74; 95% CI: -1.87 to -1.62; P<0.001]. The most common adverse events (AEs) were rash, diarrhea, fatigue, neutropenia and thrombocytopenia in both groups, but the Gem-Erlo group is more often than the gemcitabine alone (OR =1.40, 95% CI: 1.19 to 1.65; P<0.001), and all AEs were within the acceptable range for patients. CONCLUSIONS: Gem-Erlo can improve DCR when compared to gemcitabine. There was no statistically significant improvement in median PFS, median OS, ORR and 1-year survival rate. However, sensitivity analysis showed a statistical difference in the median OS. Our study indicated that Gem-Erlo had better efficacy than gemcitabine alone in PaC therapy. The occurrence of AEs is under the acceptable range for patients.

Cultures derived from pancreatic cancer xenografts with long-term gemcitabine treatment produce chemoresistant secondary xenografts: Establishment of isogenic gemcitabine-sensitive and -resistant models.

In attempts to establish sophisticated models to reproduce the process of acquired drug resistance, we transformed normal human pancreatic ductal epithelial cells by introducing genes for multiple cellular factors. We also created isogenic gemcitabine-sensitive and -resistant models by short- and long-term gemcitabine treatment, respectively. These models demonstrated differences in drug resistance in vivo, but not in vitro. Gemcitabine treatment also induced squamous transdifferentiation in xenografts in mice. The transcription factor p63 was identified as a possible resistance-determining factor but was unlikely to be solely responsible for the resistance to gemcitabine. This system would prove useful to discover novel molecular targets to overcome chemotherapy resistance, by allowing the evaluation of molecules of interest in xenograft models after in vitro genetic ablation.

Hybrid Nanoparticles of Extracellular Vesicles and Gemcitabine Prodrug-Loaded Liposomes with Enhanced Targeting Ability for Effective PDAC Treatment.

Liposomes are applied to various anticancer treatments as representative drug delivery carriers. However, liposomes do not have their own targeting properties; therefore, there are limitations in drug delivery to specific tissues or cells. High targetability in drug delivery is an important factor in improving bioavailability and drug efficacy and reducing side effects; recent research has been actively investigated to modify the surface of liposomes to give them specific functions. In this study, we studied a drug delivery system for anticancer treatment that enhances targeting ability through fusion with exosomes on the surface of liposomes. We designed exosome-liposome hybrid nanoparticles loaded with a gemcitabine prodrug as a treatment for pancreatic ductal adenocarcinoma (PDAC). Membrane fusion with exosomes shows excellent targeting ability to pancreatic cancer cells due to intrinsic targeting ability and expansion of the macropinocytosis pathway.

20(S)-Ginsenoside Rh2 overcomes gemcitabine resistance in pancreatic cancer by inhibiting LAMC2-Modulated ABC transporters.

INTRODUCTION: Gemcitabine (GEM) is the first-line drug for pancreatic ductal adenocarcinoma (PDAC), but drug resistance severely restricts its chemotherapeutic efficacy. Laminin subunit γ2 (LAMC2) plays a crucial role in extracellular matrix formation in the development of GEM-resistance. However, the biological function of LAMC2 in GEM resistance and its molecular mechanisms are still unclear. 20(S)-Ginsenoside Rh2 (Rh2), one of the principal active components isolated from Ginseng Radix et Rhizoma, possesses strong anti-tumor effects. However, the effects of Rh2 on overcoming GEM resistance and its action mechanisms remain to be elucidated. OBJECTIVES: This study aimed to determine the efficacy of Rh2 on overcoming GEM resistance and to explore its underlying molecular mechanisms. METHODS: Clinical study, Western blotting, publicly available databasesand bioinformatic analyses were performed to investigate the protein expression of LAMC2 in the GEM-resistant PDAC patients and the acquired GEM-resistant PDAC cells. Then, the effects of Rh2 on overcoming the GEM resistance in PDAC were evaluated both in vitro and in vivo. Stable silencing or overexpression of LAMC2 in the GEM-resistant PDAC cells were established for validating the role of LAMC2 on Rh2 overcoming the GEM resistance in PDAC. RESULTS: The protein expression of LAMC2 was markedly increased in the GEM-resistant PDAC patient biopsies compared to the sensitive cases. The protein expression of LAMC2 was significantly higher in the acquired GEM-resistant PDAC cells than that in their parental cells. Rh2 enhanced the chemosensitivity of GEM in the GEM-resistant PDAC cells, and inhibited the tumor growth of Miapaca-2-GR cell-bearing mice and Krastm4TyjTrp53tm1BrnTg (Pdx1-cre/Esr1*) #Dam/J (KPC) mice. Rh2 effectively reversed the GEM resistance in Miapaca-2-GR and Capan-2-GR cells by inhibiting LAMC2 expression through regulating the ubiquitin-proteasome pathway. Knockdown of LAMC2 enhanced the chemosensitivity of GEM and the effects of Rh2 on overcoming the GEM resistance in PDAC cells and the orthotopic PDAC mouse model. Conversely, LAMC2 overexpression aggravated the chemoresistance of GEM and abolished the effects of Rh2 on overcoming GEM resistance via modulating ATP-binding cassette (ABC) transporters leading to the active GEM efflux. CONCLUSIONS: LAMC2 plays an important role in the GEM resistance in PDAC, and Rh2 is a potential adjuvant for overcoming the chemoresistance of GEM in PDAC.

Thermosensitive Liposomes for Gemcitabine Delivery to Pancreatic Ductal Adenocarcinoma.

Treatment of pancreatic ductal adenocarcinoma with gemcitabine is limited by an increased desmoplasia, poor vascularization, and short plasma half-life. Heat-sensitive liposomes modified by polyethylene glycol (PEG; PEGylated liposomes) can increase plasma stability, reduce clearance, and decrease side effects. Nevertheless, translation of heat-sensitive liposomes to the clinic has been hindered by the low loading efficiency of gemcitabine and by the difficulty of inducing hyperthermia in vivo. This study was designed to investigate the effect of phospholipid content on the stability of liposomes at 37 °C and their release under hyperthermia conditions; this was accomplished by employing a two-stage heating approach. First the liposomes were heated at a fast rate, then they were transferred to a holding bath. Thermosensitive liposomes formulated with DPPC: DSPC: PEG2k (80:15:5, mole%) exhibited minimal release of carboxyfluorescein at 37 °C over 30 min, indicating stability under physiological conditions. However, upon exposure to hyperthermic conditions (43 °C and 45 °C), these liposomes demonstrated a rapid and significant release of their encapsulated content. The encapsulation efficiency for gemcitabine was calculated at 16.9%. Additionally, fluorescent analysis during the removal of unencapsulated gemcitabine revealed an increase in pH. In vitro tests with BxPC3 and KPC cell models showed that these thermosensitive liposomes induced a heat-dependent cytotoxic effect comparable to free gemcitabine at temperatures above 41 °C. This study highlights the effectiveness of the heating mechanism and cell models in understanding the current challenges in developing gemcitabine-loaded heat-sensitive liposomes.

Short-term outcomes of intravesical gemcitabine for non-muscle-invasive bladder cancer after recent approval for use in Korea.

PURPOSE: In high-risk non-muscle-invasive bladder cancer (NMIBC), intravesical Bacillus Calmette-Guérin (BCG) is the standard adjuvant therapy post-transurethral resection of bladder tumor (TURBT). Intravesical gemcitabine, used as an alternative or second-line therapy amid BCG shortages, lacks outcome studies in the Korean population. MATERIALS AND METHODS: Patients who received weekly intravesical gemcitabine for 6 weeks after TURBT from 2019 to 2022 were retrospectively investigated. Based on the American Urological Association risk classification, patients with high- or very high-risk NMIBC who refused cystectomy were included. Maintenance treatment was performed depending on their risk. Recurrence was defined as histologic confirmation on subsequent cystoscopic biopsies or TURBT. Disease free survival (DFS) was evaluated by the Kaplan-Meier method. RESULTS: The study included 60 patients, comprising 45 high-risk (group 1) patients with a median age of 76 years and 15 very high-risk (group 2) patients with a median age of 68 years. Among them, 28 patients had previously received intravesical BCG. Over a median follow-up of 22 months, recurrence occurred in 31 patients in group 1 and 11 in group 2. The DFS rates of the high-risk group and the very high-risk group were 57.8% versus 40% at 1 year, 20.7% versus 21.3% at 2 years and 20.7% versus 21.3% at 3 years, respectively (p=0.831). Tis stage (p=0.042) and prostatic urethra invasion (p=0.028) were significant predictors of DFS. Cancer-specific mortality rates were 2.2% in group 1 and 6.7% in group 2 (p=0.441). CONCLUSIONS: Similar DFS outcome between high-risk and very high-risk patients were observed based on short-term results in Korea. This finding is crucial for clinical practice; however, studies analyzing more patients and long-term outcomes are needed.

Telotristat ethyl, a tryptophan hydroxylase inhibitor, enhances antitumor efficacy of standard chemotherapy in preclinical cholangiocarcinoma models.

Cholangiocarcinoma (CCA), an aggressive biliary tract cancer, carries a grim prognosis with a 5-year survival rate of 5%-15%. Standard chemotherapy regimens for CCA, gemcitabine plus cisplatin (GemCis) or its recently approved combination with durvalumab demonstrate dismal clinical activity, yielding a median survival of 12-14 months. Increased serotonin accumulation and secretion have been implicated in the oncogenic activity of CCA. This study investigated the therapeutic efficacy of telotristat ethyl (TE), a tryptophan hydroxylase inhibitor blocking serotonin biosynthesis, in combination with standard chemotherapies in preclinical CCA models. Nab-paclitaxel (NPT) significantly enhanced animal survival (60%), surpassing the marginal effects of TE (11%) or GemCis (9%) in peritoneal dissemination xenografts. Combining TE with GemCis (26%) or NPT (68%) further increased survival rates. In intrahepatic (iCCA), distal (dCCA) and perihilar (pCCA) subcutaneous xenografts, TE exhibited substantial tumour growth inhibition (41%-53%) compared to NPT (56%-69%) or GemCis (37%-58%). The combination of TE with chemotherapy demonstrated enhanced tumour growth inhibition in all three cell-derived xenografts (67%-90%). PDX studies revealed TE's marked inhibition of tumour growth (40%-73%) compared to GemCis (80%-86%) or NPT (57%-76%). Again, combining TE with chemotherapy exhibited an additive effect. Tumour cell proliferation reduction aligned with tumour growth inhibition in all CDX and PDX tumours. Furthermore, TE treatment consistently decreased serotonin levels in all tumours under all therapeutic conditions. This investigation decisively demonstrated the antitumor efficacy of TE across a spectrum of CCA preclinical models, suggesting that combination therapies involving TE, particularly for patients exhibiting serotonin overexpression, hold the promise of improving clinical CCA therapy.

Prognostic value of nucleotide excision repair and translesion DNA synthesis proteins in muscle-infiltrating bladder carcinoma.

BACKGROUND: Cisplatin (CDDP) remains a key agent in the treatment of muscle-infiltrating bladder carcinoma (MIBC). However, a proportion of MIBC patients do not respond to chemotherapy, which may be caused by the increased repair of CDDP-induced DNA damage. The purpose of this study was to explore the prognostic value of proteins involved in nucleotide excision repair (NER) and translesion DNA synthesis (TLS) in MIBC patients. METHODS: This is a retrospective analysis of 86 MIBC patients. The XPA, XPF, XPG, ERCC1, POLI, POLH and REV3L proteins were stained in primary bladder tumors and their levels were analyzed both in the total cohort and in a subgroup with metastatic urothelial carcinoma (mUC) that received gemcitabine and CDDP as a first-line therapy. Both cohorts were divided by percentage of cancer cells stained positive for each protein into subgroups with high and low expression. In the same manner, the combined expression of NER (XPA + ERCC1 + XPF + XPG) and TLS (POLI + POLH + REV3L), as the whole pathways, was analyzed. RESULTS: Mortality was 89.5% at the median follow-up of 120.2 months. In the total cohort, patients with tumors stained positive for XPA, XPG and POLI had significantly worse overall survival (OS) compared to those with negative staining [hazard ratio (HR) = 0.60, 0.62 and 0.53, respectively]. Both XPG and POLI were independent prognostic factors in multivariate analyses (MVA). In addition, an increase in NER and TLS pathway expression was significantly associated with worse OS in the total cohort (HR = 0.54 and 0.60, respectively). In the mUC subgroup, high POLI expression was associated with significant deterioration of OS (HR = 0.56) in univariate analyses, and its independent prognostic value was shown in MVA. CONCLUSIONS: Our study showed significant correlations between the tumor expression of XPG and POLI, as well as NER and TLS as the whole pathways, and inferior OS. Hence, they could constitute prognostic biomarkers and potentially promising therapeutic targets in MIBC. However, a prospective trial is required for further validation, thereby overcoming the limitations of this study.

Tumor-derived exosome PPP3CB induce gemcitabine resistance by regulating miR-298/STAT3 in pancreatic cancer.

Purpose: Due to resistance to gemcitabine (GEM), patients with pancreatic cancer (PC) usually have poor prognosis and low survival rate. The purpose of our research was to explore the impact of exosome PPP3CB on GEM resistance in PC, and concurrently analyze the regulatory role of the miR-298/STAT3 signaling pathway. Methods: Exosomes isolated from PC cells were verified by transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA) and western blotting (WB). The interaction between PPP3CB and miR-298 was verified using dual-luciferase reporter gene assay, followed by evaluation of cell growth and death using CCK8 assay, EdU staining, and flow cytometry. Results: Increased PPP3CB expression was observed in GEM-resistant PC cells. Exosomes from PC cells and GEM-resistant PC cells were successfully extracted by ultra-high speed centrifugation. Confocal microscopy showed internalization of fluorescein amide (FAM)-labeled GEM-resistant exosomes by PC cells. PPP3CB enhanced the proliferation of GEM-resistant PC cells and inhibited their apoptosis, whereas down-regulation of PPP3CB promoted the death of PC cells and inhibited the proliferation of GEM-resistant PC cells, and enhance the susceptibility of PC cells to GEM. Additionally, PPP3CB positively regulated STAT3 expression in PC cells by down-regulating miR-298, thus promoting the growth and inhibiting the death of PC cells. Conclusion: PC cell-derived exosome PPP3CB enhances STAT3 expression by downregulating miR-298, stimulating cell growth, and suppressing cell death, thereby increasing the resistance of PC cells to GEM.

Safety of pressurized intraperitoneal aerosolized chemotherapy in biliary cancer patients with peritoneal metastases.

Biliary tract cancers are a rare diagnosis with a rising incidence. Up to 20% of patients have peritoneal metastases, resulting in symptoms of ascites, abdominal pain and potential bowel obstruction. A standard of care systemic treatment comprises gemcitabine, cisplatin and durvalumab (gem/cis/durva). However, the clinical benefit among patients with peritoneal metastases remains unknown. Pressurized intraperitoneal aerosolized chemotherapy (PIPAC) delivers chemotherapy directly to the peritoneal space, which could potentially improve efficacy with minimal systemic toxicity. We describe the design of a Phase I study investigating PIPAC with nab-paclitaxel plus systemic gem/cis/durva among biliary tract cancer patients with peritoneal metastases who have not received prior systemic treatment. The primary end point is safety of PIPAC with nab-paclitaxel in combination with systemic gem/cis/durva.Clinical Trial Registration: NCT05285358 (ClinicalTrials.gov).

[Box: see text].

Comparative Effectiveness of Bacillus Calmette-Guérin and Sequential Intravesical Gemcitabine and Docetaxel for Treatment-naïve Intermediate-risk Non-muscle-invasive Bladder Cancer.

BACKGROUND AND OBJECTIVE: Sequential intravesical gemcitabine/docetaxel (Gem/Doce) has emerged as a potential alternative to bacillus Calmette-Guérin (BCG) for the treatment of non-muscle-invasive bladder cancer (NMIBC). Our aim was to determine the comparative effectiveness of BCG and Gem/Doce for patients with intermediate-risk (IR) NMIBC, composed mainly of high-grade (HG) Ta disease. METHODS: Patients with IR-NMIBC who received either BCG or Gem/Doce during 2013-2023 were included. Maintenance BCG (as per the Southwest Oncology Group protocol) and monthly Gem/Doce maintenance for 1 yr were offered to patients with no evidence of recurrence after induction. Routine surveillance with cystoscopy was performed according to the American Urological Association guidelines. The Kaplan-Meier method was used to assess high-grade and any-grade recurrence-free survival (RFS). Cox regression analysis was performed to find predictors of recurrence. KEY FINDINGS AND LIMITATIONS: Of 483 patients, 127 had IR-NMIBC; 66 patients received BCG and 61 received Gem/Doce. Median age was 69 yr (interquartile range [IQR] 61-76) for the BCG group and 72 yr (IQR 62-76) for the Gem/Doce group. Median follow-up was 53.1 mo (IQR 25.3-71.2) for the BCG group and 20.2 mo (IQR 8.28-33.1) for the Gem/Doce group. The 2-yr high-grade RFS rates for primary high-grade tumors for BCG versus Gem/Doce groups were 81% versus 61%, with corresponding any-grade RFS rates of 60% versus 41%. Induction with Gem/Doce predicted any-grade recurrence (hazard ratio [HR] 1.87, 95% confidence interval [CI] 1.1-3.2) and high-grade recurrence for primary high-grade tumors (HR 3.4 95% CI 1.27-9.13), while receipt of maintenance therapy decreased the risk of any-grade recurrence (HR 0.4, 95% CI 0.22-0.72). This study is limited by its retrospective design. CONCLUSIONS AND CLINICAL IMPLICATIONS: For patients with IR-NMIBC, BCG was associated with superior any-grade RFS and high-grade RFS for primary high-grade tumors. Maintenance therapy was associated with better RFS when receiving Gem/Doce. Standardization and longer maintenance therapy protocols should be considered for Gem/Doce treatment. PATIENT SUMMARY: We compared outcomes for patients who received two different in-bladder treatments for intermediate-risk bladder cancer. Bacillus Calmette-Guérin (BCG) led to better outcomes than gemcitabine + docetaxel (Gem/Doce). Monthly maintenance therapy improved recurrence-free survival for patients who received Gem/Doce. We conclude that maintenance therapy is essential for patients receiving Gem/Doce to avoid bladder cancer recurrence after treatment.