Defining the mode of action of cisplatin combined with NUC-1031, a phosphoramidate modification of gemcitabine.

The combination of gemcitabine with platinum agents is a widely used chemotherapy regimen for a number of tumour types. Gemcitabine plus cisplatin remains the current therapeutic choice for biliary tract cancer. Gemcitabine is associated with multiple cellular drug resistance mechanisms and other limitations and has thereforelined in use. NUC-1031 (Acelarin) is a phosphorylated form of gemcitabine, protected by the addition of a phosphoramidate moiety, developed to circumvent the key limitations and generate high levels of the cytotoxic metabolite, dFdCTP. The rationale for combination of gemcitabine and cisplatin is determined by in vitro cytotoxicity. This, however, does not offer an explanation of how these drugs lead to cell death. In this study we investigate the mechanism of action for NUC-1031 combined with cisplatin as a rationale for treatment. NUC-1031 is metabolised to dFdCTP, detectable up to 72 h post-treatment and incorporated into DNA, to stall the cell cycle and cause DNA damage in biliary tract and ovarian cancer cell lines. In combination with cisplatin, DNA damage was increased and occurred earlier compared to monotherapy. The damage associated with NUC-1031 may be potentiated by a second mechanism, via binding the RRM1 subunit of ribonucleotide reductase and perturbing the nucleotide pools; however, this may be mitigated by increased RRM1 expression. The implication of this was investigated in case studies from a Phase I clinical trial to observe whether baseline RRM1 expression in tumour tissue at time of diagnosis correlates with patient survival.

The efficacy of gemcitabine and docetaxel chemotherapy for the treatment of relapsed and refractory osteosarcoma: A systematic review and pre-clinical study.

INTRODUCTION: Osteosarcoma is the most common primary malignancy of the bone. There is a lack of effective treatments for patients who experience relapsed osteosarcoma. One treatment for relapsed patients is gemcitabine and docetaxel combination chemotherapy (GEMDOX). This systematic review aimed to establish the efficacy of this chemotherapy regimen, as well as identify the common severe toxicities that are associated with it. Resistant osteosarcoma cell lines developed from MG-63 and HOS-143B were used to represent relapsed osteosarcoma patients in a pre-clinical study. RESULTS: We identified 11 retrospective and Phase II studies that were suitable for inclusion in our review. 10.65% of patients had a response to gemcitabine and docetaxel combination therapy and the disease control rate was 35% (n = 197). 36%, 35.3% and 18.04% of patients experienced grade 3 or 4 neutropenia, thrombocytopenia and anaemia respectively (n = 133). Male patients (X2 = 9.14, p < 0.05) and those below the age of 18 (X 2 = 10.94, p < 0.05) responded better to GEMDOX treatment than females and patients older than 18 years. The resistant osteosarcoma cell lines remained sensitive to either single-agent gemcitabine, docetaxel, and the combination of both. Cisplatin-resistant models (MG-63/CISR8 & HOS-143B/CISR8) were the most responsive to GEMDOX treatment compared to doxorubicin, methotrexate, and triple-combination resistant models. CONCLUSION: GEMDOX treatment has potential efficacy in relapsed osteosarcoma patients especially those with cisplatin resistance. To directly compare the efficacy of GEMDOX therapy against other therapies randomised phase III clinical trials with adequate patient follow up must be performed to improve treatment options for osteosarcoma.

Efficacy, safety and differential outcomes of immune-chemotherapy with gemcitabine, cisplatin and durvalumab in patients with biliary tract cancers: A multicenter real world cohort.

BACKGROUND: Combined Immuno-chemotherapy consisting of gemcitabine, cisplatin and the programmed death-ligand one inhibitor durvalumab (GCD) is the new standard of care for patients with biliary tract cancers (BTC) based on positive results of the TOPAZ-1 study. OBJECTIVE: We here evaluated the efficacy and safety of GCD for BTC in a German multicenter real-world patient cohort. METHODS: Patients with BTC treated with GCD from 9 German centers were included. Clinicopathological baseline parameters, overall survival (OS), response rate and adverse events (AEs) were retrospectively analyzed. The prognostic impact was determined by Kaplan-Meier analyses and Cox regression models. RESULTS: A total of 165 patients treated with GCD between 2021 and 2024 were included in the study. Median OS and median progression-free survival were 14 months (95% CI 10.3-17.7) and 8 months (95% CI 6.8-9.2), respectively. The best overall response rate was 28.5% and disease control rate was 65.5%. While extrahepatic and intrahepatic BTC showed similar outcomes, mOS was significantly shorter in patients with gall bladder cancer (GB-CA) with 9 months (95% CI 5.5-12.4; p = 0.02). In univariate analyses age ≥70 years, Eastern Cooperative Oncology Group (ECOG) performance status (PS) ≥1, status post cholecystectomy, GB-CA and high baseline CRP values were significantly associated with OS. ECOG PS ≥ 1 and GB-CA remained independent prognostic factors for OS in multivariable cox regression analysis. AEs have been reported in 130 patients (78.8%), including 149 grade 3-4 AEs (25.5%). One patient died of severe infectious pneumonia. Immune-related (ir)AEs occurred in 17 patients (10.3%), including 9 grade 3-4 irAEs (2.2%), which led to treatment interruption in 4 patients. CONCLUSIONS: Immuno-chemotherapy in patients with BTC was feasible, effective and safe in a real-life scenario. Our results were comparable to the phase 3 clinical trial results (TOPAZ-1). Reduced efficacy was noted in patients with GB-CA and/or a reduced performance status that warrants further investigation.

Economic evaluation of NALIRIFOX vs. nab-paclitaxel and gemcitabine regimens for first-line treatment of metastatic pancreatic ductal adenocarcinoma from U.S. perspective.

BACKGROUND: The cost-effectiveness of NALIRIFOX as a potential new standard of care for patients with metastatic pancreatic ductal adenocarcinoma (mPDAC) has yet to be established. Our objective was to evaluate the cost-effectiveness of NALIRIFOX vs. nab-paclitaxel and gemcitabine in this indication from the perspective of U.S. public payers. METHODS: A partitioned survival model was constructed from the perspective of U.S. public payers, drawing on baseline patient characteristics and vital clinical data from the NAPOLI-3 trial. Costs and utilities were sourced from publicly accessible databases and literature. A lifetime horizon was applied, with an annual discount rate of 3%. We calculated and compared cumulative costs, life years, quality-adjusted life years (QALYs), and incremental cost-effectiveness ratios (ICER). To evaluate the model's robustness, sensitivity analyses, scenario analyses, and subgroup analyses were carried out. Additionally, a price simulation for the costly liposomal irinotecan was conducted to inform the pricing strategy at the given willingness to pay (WTP) threshold. RESULTS: In the base-case analysis, NALIRIFOX provided an additional 0.29 QALYs with an ICER of $206,340.69 /QALY compared to nab-paclitaxel and gemcitabine, indicating it is not cost-effective at a $150,000/QALY threshold. Sensitivity analysis showed the model was most sensitive to the costs of liposomal irinotecan, capecitabine, and post-progression care. Probabilistic sensitivity analysis indicated a 17.66% probability of NALIRIFOX being cost-effective at $150,000/QALY, rising to 47.48% at $200,000/QALY. Pricing simulations suggested NALIRIFOX could become cost-effective at $150,000/QALY if the price of irinotecan liposome drops to $53.24/mg (a 14.8% reduction). CONCLUSIONS: NALIRIFOX may not be cost-effective at its current price as a first-line treatment for patients with mPDAC in the long term. The cost of liposomal irinotecan has the greatest impact. It may become cost-effective only if its cost is reduced by 14.8%, with a WTP threshold of $150,000 /QALY.

Randomized phase 2 study of valproic acid combined with simvastatin and gemcitabine/nab-paclitaxel-based regimens in untreated metastatic pancreatic adenocarcinoma patients: the VESPA trial study protocol.

BACKGROUND: Metastatic pancreatic ductal adenocarcinoma (mPDAC) patients have very poor prognosis highlighting the urgent need of novel treatments. In this regard, repurposing non-oncology already-approved drugs might be an attractive strategy to offer more-effective treatment easily tested in clinical trials. Accumulating evidence suggests that epigenetic deregulation is a hallmark of cancer contributing to treatment resistance in several solid tumors, including PDAC. Histone deacetylase inhibitors (HDACi) are epigenetic drugs we have investigated preclinically and clinically as anticancer agents. Valproic acid (VPA) is a generic low-cost anticonvulsant and mood stabilizer with HDAC inhibitory activity, and anticancer properties also demonstrated in PDAC models. Statins use was reported to be associated with lower mortality risk in patients with pancreatic cancer and statins have been shown to have a direct antitumor effect when used alone or in combination therapy. We recently showed capability of VPA/Simvastatin (SIM) combination to potentiate the antitumor activity of gemcitabine/nab-paclitaxel in vitro and in vivo PDAC preclinical models. METHODS/DESIGN: VESPA is a patient-centric open label randomized multicenter phase-II investigator-initiated trial, evaluating the feasibility, safety, and efficacy of VPA/SIM plus first line gemcitabine/nab-paclitaxel-based regimens (AG or PAXG) (experimental arm) versus chemotherapy alone (standard arm) in mPDAC patients. The study involves Italian and Spanish oncology centers and includes an initial 6-patients safety run-in-phase. A sample size of 240 patients (120 for each arm) was calculated under the hypothesis that the addition of VPA/SIM to gemcitabine and nab-paclitaxel-based regimens may extend progression free survival from 6 to 9 months in the experimental arm. Secondary endpoints are overall survival, response rate, disease control rate, duration of response, CA 19.9 reduction, toxicity, and quality of life. The study includes a patient engagement plan and complementary biomarkers studies on tumor and blood samples. CONCLUSIONS: VESPA is the first trial evaluating efficacy and safety of two repurposed drugs in oncology such as VPA and SIM, in combination with standard chemotherapy, with the aim of improving mPDAC survival. The study is ongoing. Enrollment started in June 2023 and a total of 63 patients have been enrolled as of June 2024. TRIAL REGISTRATION: EudraCT number: 2022-004154-63; ClinicalTrials.gov identifier NCT05821556, posted 2023/04/20.

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.

G3BP2 promotes tumor progression and gemcitabine resistance in PDAC via regulating PDIA3-DKC1-hENT in a stress granules-dependent manner.

Pancreatic ductal adenocarcinoma (PDAC) is distinguished by its aggressive malignancy, limited treatment avenues and a tendency towards chemotherapy resistance, underscoring the critical need for advanced research to uncover new therapeutic approaches. Stress granules (SGs) that is implicated in cellular self-protection mechanism, along with its associated family molecules have shown pro-cancer effects and are closely related to tumor chemotherapy resistance. In this study we investigated the relationship between Ras GTPase-activating protein-binding proteins 2 (G3BP2), a core component of SGs, and the malignancy of PDAC as well as its resistance to the chemotherapy drug gemcitabine. Analyzing TCGA dataset revealed that the expression of G3BP1 and G3BP2 was significantly upregulated in PDAC compared with adjacent normal pancreatic tissues, and the high expression of G3BP2 rather than G3BP1 was significantly associated with poorer overall survival (OS) in PDAC patients. We demonstrated that knockdown of G3BP2 inhibited the proliferation and invasion of PANC-1 and CFPAC-1 cells in vitro and in vivo. By analyzing the differentially expressed genes in G3BP2 knockdown and overexpressed PANC-1 cells, we identified DKC1 that was associated with RNA stability and regulation as the target of G3BP2. We demonstrated that G3BP2 bound to PDIA3 mRNA and recruited them into SGs, increasing the stability of PDIA3 mRNA and attenuating its translation efficiency, thereby promoting DKC1 expression. Furthermore, DKC1 could bind to hENT mRNA and inhibited its expression, which enhanced gemcitabine resistance of PDAC. Therefore, we propose a novel mechanism wherein G3BP2 facilitates PDAC's resistance to chemotherapy by modulating PDIA3-DKC1-hENT in a SGs-dependent way, suggesting G3BP2 SGs a protentional therapeutic target for the treatment in PDAC.

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].

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.

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.

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.

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.

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.

Knockdown of cullin 3 inhibits progressive phenotypes and increases chemosensitivity in cholangiocarcinoma cells.

Cholangiocarcinoma (CCA) is an extremely aggressive malignancy arising from the epithelial cells lining the bile ducts. It presents a substantial global health issue, with the highest incidence rates, ranging from 40­100 cases/100,000 individuals, found in Southeast Asia, where liver fluke infection is endemic. In Europe and America, incidence rates range from 0.4­2 cases/100,000 individuals. Globally, mortality rates range from 0.2­2 deaths/100,000 person­years and are increasing in most countries. Chemotherapy is the primary treatment for advanced CCA due to limited options from late­stage diagnosis, but its efficacy is hindered by drug­resistant phenotypes. In a previous study, proteomics analysis of drug­resistant CCA cell lines (KKU­213A­FR and KKU­213A­GR) and the parental KKU­213A line identified cullin 3 (Cul3) as markedly overexpressed in drug­resistant cells. Cul3, a scaffold protein within CUL3­RING ubiquitin ligase complexes, is crucial for ubiquitination and proteasome degradation, yet its role in drug­resistant CCA remains to be elucidated. The present study aimed to elucidate the role of Cul3 in drug­resistant CCA cell lines. Reverse transcription­quantitative PCR and western blot analyses confirmed significantly elevated Cul3 mRNA and protein levels in drug­resistant cell lines compared with the parental control. Short interfering RNA­mediated Cul3 knockdown sensitized cells to 5­fluorouracil and gemcitabine and inhibited cell proliferation, colony formation, migration and invasion. In addition, Cul3 knockdown induced G0/G1 cell cycle arrest and suppressed key cell cycle regulatory proteins, cyclin D, cyclin­dependent kinase (CDK)4 and CDK6. Bioinformatics analysis of CCA patient samples using The Cancer Genome Atlas data revealed Cul3 upregulation in CCA tissues compared with normal bile duct tissues. STRING analysis of upregulated proteins in drug­resistant CCA cell lines identified a highly interactive Cul3 network, including COMM Domain Containing 3, Ariadne RBR E3 ubiquitin protein ligase 1, Egl nine homolog 1, Proteasome 26S Subunit Non­ATPase 13, DExH­box helicase 9 and small nuclear ribonucleoprotein polypeptide G, which showed a positive correlation with Cul3 in CCA tissues. Knocking down Cul3 significantly suppressed the mRNA expression of these genes, suggesting that Cul3 may act as an upstream regulator of them. Gene Ontology analysis revealed that the majority of these genes were categorized under binding function, metabolic process, cellular anatomical entity, protein­containing complex and protein­modifying enzyme. Taken together, these findings highlighted the biological and clinical significance of Cul3 in drug resistance and progression of CCA.

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.

Phase II study of pegaspargase, etoposide, gemcitabine (PEG) followed by involved-field radiation therapy in early-stage extranodal natural killer/T-cell lymphoma.

OBJECTIVE: The prognosis of extra-nodal NK/T cell lymphoma (ENKTL) is poor, and the optimal therapy remains controversial. This study aims to evaluate the safety and efficacy of a new combined modality therapy. METHODS: Phase-2 study of pegaspargase, etoposide and gemcitabine (PEG) combined with involved field radiation therapy (IFRT) in newly-diagnosed patients with early-stage ENKTL. Patients received 4 course of PEG followed by IFRT. The primary endpoints were complete response (CR), partial response (PR), and objective response rate (ORR) after IFRT. Secondary endpoints included progression-free survival (PFS), overall survival (OS) and adverse events. RESULTS: 34 consecutive patients with Ann Arbor stage I/II were enrolled. 3 patients progressed on PEG, while the remaining 31 received IFRT. The ORR was 88.2% (30/34), included 28 (82.4%) complete and 2 (5.8%) partial responses. With a median follow-up of 56.0 months (Interquartile Range [IQR], 36.0-66.9 months), the estimated 5-year PFS and OS were 87.4% (95% Confidence Interval [CI],69.5%-94.8%) and 97.1% (95%CI, 80.1%-99.6%), respectively. Most adverse events were hematological and easily managed. CONCLUSIONS: PEG followed by IFRT is a safe and effective initial therapy for early-stage ENKTL, demonstrating impressive PFS and OS rates. This promising approach warrants further validation in a randomized controlled trial (Registered at Clinicaltrials.gov NCT02705508).Trial registration: ClinicalTrials.gov identifier: NCT02705508.

Novel Tubeimoside I liposomal drug delivery system in combination with gemcitabine for the treatment of pancreatic cancer.

Aim: To evaluate the anti-pancreatic cancer effect of novel Tubeimoside I multifunctional liposomes combined with gemcitabine.Methods: Liposomes were prepared through the thin film hydration method, with evaluations conducted on parameters including encapsulation efficiency (EE%), particle size, polydispersity index (PDI), zeta potential (ZP), storage stability, and release over a 7-day period. The cellular uptake rate, therapeutic efficacy in vitro and in vivo and the role of immune microenvironment modulation were evaluated.Results: The novel Tubeimoside I multifunctional liposomal exhibited good stability, significant anti-cancer activity, and immune microenvironment remodeling effects. Furthermore, it showed a safety profile.Conclusion: This study underscores the potential of Novel Tubeimoside I multifunctional liposomal as a promising treatment option for pancreatic cancer.

[Box: see text].

YBX1 as a therapeutic target to suppress the LRP1-ß-catenin-RRM1 axis and overcome gemcitabine resistance in pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) is highly malignant and has a poor prognosis, without effective therapeutic targets in common gene mutations. Gemcitabine, a first-line chemotherapeutic for PDAC, confers <10 % 5-year survival rate because of drug resistance. Y-box binding protein 1 (YBX1), associated with multidrug-resistance gene activation, remains unelucidated in PDAC gemcitabine resistance. In vivo and in vitro, we verified YBX1's promotional effects, especially gemcitabine resistance, in pancreatic cancer cells. YBX1-induced LRP1 transcription by binding to the LRP1 promoter region significantly altered the concentration and distribution of ß-catenin in pancreatic cancer cells. Through TCF3, ß-catenin bound to the promoter region of RRM1, a key gene for gemcitabine resistance, that promotes RRM1 expression. Combination therapy with the YBX1 inhibitor SU056 and gemcitabine effectively reduced gemcitabine resistance in in vivo and in vitro experiments. High YBX1 expression promoted pathogenesis and gemcitabine resistance in pancreatic cancer through the YBX1-LRP1-ß-catenin-RRM1 axis. Combining YBX1 inhibitors with gemcitabine may provide a new direction for combination chemotherapy to overcome gemcitabine resistance, which frequently occurs during chemotherapy for pancreatic cancer.