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Respiratory Research May 2024Mitogen-activated protein kinase (MAPK)signaling-mediated smoking-associated pulmonary vascular remodeling (PVR) plays an important role in the pathogenesis of group 3...
BACKGROUND
Mitogen-activated protein kinase (MAPK)signaling-mediated smoking-associated pulmonary vascular remodeling (PVR) plays an important role in the pathogenesis of group 3 pulmonary hypertension (PH). And G protein pathway suppressor 2 (GPS2) could suppress G-protein signaling such as Ras and MAPK, but its role in cigarette smoking -induced PVR (CS-PVR) is unclear.
METHODS
An in vivo model of smoke-exposed rats was constructed to assess the role of GPS2 in smoking-induced PH and PVR. In vitro, the effects of GPS2 overexpression and silencing on the function of human pulmonary arterial smooth cells (HPASMCs) and the underlying mechanisms were explored.
RESULTS
GPS2 expression was downregulated in rat pulmonary arteries (PAs) and HPASMCs after CS exposure. More importantly, CS-exposed rats with GPS2 overexpression had lower right ventricular systolic pressure (RVSP), right ventricular hypertrophy index (RVHI), and wall thickness (WT%) than those without. And enhanced proliferation and migration of HPASMCs induced by cigarette smoking extract (CSE) can be evidently inhibited by overexpressed GPS2. Besides, GPS2siRNA significantly enhanced the proliferation, and migration of HPASMCs as well as activated Ras and Raf/ERK signaling, while these effects were inhibited by zoledronic acid (ZOL). In addition, GPS2 promoter methylation level in rat PAs and HPASMCs was increased after CS exposure, and 5-aza-2-deoxycytidine (5-aza) inhibited CSE-induced GPS2 hypermethylation and downregulation in vitro.
CONCLUSIONS
GPS2 overexpression could improve the CS-PVR, suggesting that GPS2 might serve as a novel therapeutic target for PH-COPD in the future.
Topics: Animals; Vascular Remodeling; Rats; Male; Rats, Sprague-Dawley; Humans; Cigarette Smoking; MAP Kinase Signaling System; Cells, Cultured; ras Proteins; Pulmonary Artery; raf Kinases; Hypertension, Pulmonary; Extracellular Signal-Regulated MAP Kinases
PubMed: 38755610
DOI: 10.1186/s12931-024-02831-0 -
Neoplasia (New York, N.Y.) Jul 2024Pancreatic ductal adenocarcinoma (PDAC) poorly responds to antineoplastic agents. Discrepancies between preclinical success and clinical failure of compounds has been a...
BACKGROUND
Pancreatic ductal adenocarcinoma (PDAC) poorly responds to antineoplastic agents. Discrepancies between preclinical success and clinical failure of compounds has been a continuous challenge and major obstacle in PDAC research.
AIM
To investigate the association of the tumor microenvironment (TME) composition and gemcitabine metabolizing enzyme (GME) expression in vitro and several in vivo models.
METHODS
mRNA expression and protein levels of GME (cytosolic 5'-nucleotidase 1 A; NT5C1A, cytidine deaminase; CDA, deoxycytidine kinase; DCK), gemcitabine transporters (ENT1, ENT2, RRM1, RRM2) and stromal components (hyaluroninc acid, podoplanin, masson trichrome, picrosirius) were assessed by qRT-PCR and immunohistochemistry in murine LSL-Kras;LSL-Trp53; Pdx-1-Cre (KPC), orthotopically transplanted mice (OTM), human primary resected PDAC tissue (hPRT), corresponding patient-derived xenograft (PDX) mice, and KPC-SPARC mice. mRNA expression of GME was analyzed in PDAC cell lines (Panc-1, MIA PaCa, BXPC3 and L3.6) upon incubation on collagen or pancreatic stellate cell (PSC) conditioned media by qRT-PCR.
RESULTS
Endogenous KPC tumors exhibited significantly higher levels of GME compared to OTM. However, GME levels did not differ between hPRT and corresponding PDX mice. Using Kendalls Tau correlation coefficient we did not show a significant correlation of GME and components of the TME except for NT5C1A and hyaluronic acid in PDX mice (p=0.029). GME were not significantly altered upon SPARC depletion in vivo, and upon treatment with PSC-conditioned media or incubation on collagen plated dishes in vitro.
CONCLUSIONS
Our findings suggest that the expression of GME is independent from the deposition of stromal components. KPC mice are most appropriate to study stromal composition whereas PDX mice maintain GME expression of the corresponding hPRT and could be best suited for pharmacokinetic studies.
Topics: Animals; Gemcitabine; Deoxycytidine; Mice; Humans; Pancreatic Neoplasms; Tumor Microenvironment; Cell Line, Tumor; Disease Models, Animal; Stromal Cells; Carcinoma, Pancreatic Ductal; Xenograft Model Antitumor Assays; Antimetabolites, Antineoplastic; Gene Expression Regulation, Neoplastic
PubMed: 38744194
DOI: 10.1016/j.neo.2024.101002 -
PloS One 2024Therapeutic options for managing Pancreatic ductal adenocarcinoma (PDAC), one of the deadliest types of aggressive malignancies, are limited and disappointing....
pH-responsive targeted nanoparticles release ERK-inhibitor in the hypoxic zone and sensitize free gemcitabine in mutant K-Ras-addicted pancreatic cancer cells and mouse model.
Therapeutic options for managing Pancreatic ductal adenocarcinoma (PDAC), one of the deadliest types of aggressive malignancies, are limited and disappointing. Therefore, despite suboptimal clinical effects, gemcitabine (GEM) remains the first-line chemotherapeutic drug in the clinic for PDAC treatment. The therapeutic limitations of GEM are primarily due to poor bioavailability and the development of chemoresistance resulting from the addiction of mutant-K-RAS/AKT/ERK signaling-mediated desmoplastic barriers with a hypoxic microenvironment. Several new therapeutic approaches, including nanoparticle-assisted drug delivery, are being investigated by us and others. This study used pH-responsive nanoparticles encapsulated ERK inhibitor (SCH772984) and surface functionalized with tumor-penetrating peptide, iRGD, to target PDAC tumors. We used a small molecule, SCH772984, to target ERK1 and ERK2 in PDAC and other cancer cells. This nanocarrier efficiently released ERKi in hypoxic and low-pH environments. We also found that the free-GEM, which is functionally weak when combined with nanoencapsulated ERKi, led to significant synergistic treatment outcomes in vitro and in vivo. In particular, the combination approaches significantly enhanced the GEM effect in PDAC growth inhibition and prolonged survival of the animals in a genetically engineered KPC (LSL-KrasG12D/+/LSL-Trp53R172H/+/Pdx-1-Cre) pancreatic cancer mouse model, which is not observed in a single therapy. Mechanistically, we anticipate that the GEM efficacy was increased as ERKi blocks desmoplasia by impairing the production of desmoplastic regulatory factors in PDAC cells and KPC mouse tumors. Therefore, 2nd generation ERKi (SCH 772984)-iRGD-pHNPs are vital for the cellular response to GEM and denote a promising therapeutic target in PDAC with mutant K-RAS.
Topics: Animals; Deoxycytidine; Gemcitabine; Pancreatic Neoplasms; Mice; Humans; Cell Line, Tumor; Nanoparticles; Hydrogen-Ion Concentration; Carcinoma, Pancreatic Ductal; Proto-Oncogene Proteins p21(ras); Mutation; Protein Kinase Inhibitors; Disease Models, Animal; Tumor Microenvironment
PubMed: 38687749
DOI: 10.1371/journal.pone.0297749 -
JCO Precision Oncology Apr 2024The multicenter, open-label, randomized phase 2 NCI-9944 study (NCT02595892) demonstrated that addition of ATR inhibitor (ATRi) berzosertib to gemcitabine increased... (Randomized Controlled Trial)
Randomized Controlled Trial
PURPOSE
The multicenter, open-label, randomized phase 2 NCI-9944 study (NCT02595892) demonstrated that addition of ATR inhibitor (ATRi) berzosertib to gemcitabine increased progression-free survival (PFS) compared to gemcitabine alone (hazard ratio [HR]=0.57, one-sided log-rank = .044, which met the one-sided significance level of 0.1 used for sample size calculation).
METHODS
We report here the final overall survival (OS) analysis and biomarker correlations (ATM expression by immunohistochemistry, mutational signature 3 and a genomic biomarker of replication stress) along with post-hoc exploratory analyses to adjust for crossover from gemcitabine to gemcitabine/berzosertib.
RESULTS
At the data cutoff of January 27, 2023 (>30 months of additional follow-up from the primary analysis), median OS was 59.4 weeks with gemcitabine/berzosertib versus 43.0 weeks with gemcitabine alone (HR 0.79, 90% CI 0.52 to 1.2, one-sided log-rank = .18). An OS benefit with addition of berzosertib to gemcitabine was suggested in patients stratified into the platinum-free interval ≤3 months (N = 26) subgroup (HR, 0.48, 90% CI 0.22 to 1.01, one-sided log-rank =.04) and in patients with ATM-negative/low (N = 24) tumors (HR, 0.50, 90% CI 0.23 to 1.08, one-sided log-rank = .06).
CONCLUSION
The results of this follow-up analysis continue to support the promise of combined gemcitabine/ATRi therapy in platinum resistant ovarian cancer, an active area of investigation with several ongoing clinical trials.
Topics: Humans; Female; Gemcitabine; Deoxycytidine; Carcinoma, Ovarian Epithelial; Protein Kinase Inhibitors; Ovarian Neoplasms; Ataxia Telangiectasia Mutated Proteins; Isoxazoles; Pyrazines
PubMed: 38635934
DOI: 10.1200/PO.23.00635 -
Mitochondrion May 2024Thymidine kinase 2 deficiency (TK2d) is a rare autosomal recessive mitochondrial disorder. It manifests as a continuous clinical spectrum, from fatal infantile...
OBJECTIVES
Thymidine kinase 2 deficiency (TK2d) is a rare autosomal recessive mitochondrial disorder. It manifests as a continuous clinical spectrum, from fatal infantile mitochondrial DNA depletion syndromes to adult-onset mitochondrial myopathies characterized by ophthalmoplegia-plus phenotypes with early respiratory involvement. Treatment with pyrimidine nucleosides has recently shown striking effects on survival and motor outcomes in the more severe infantile-onset clinical forms. We present the response to treatment in a patient with adult-onset TK2d.
METHODS
An adult with ptosis, ophthalmoplegia, facial, neck, and proximal muscle weakness, non-invasive nocturnal mechanical ventilation, and dysphagia due to biallelic pathogenic variants in TK2 received treatment with 260 mg/kg/day of deoxycytidine (dC) and deoxythymidine (dT) under a Compassionate Use Program. Prospective motor and respiratory assessments are presented.
RESULTS
After 27 months of follow-up, the North Star Ambulatory Assessment improved by 11 points, he walked 195 m more in the 6 Minute-Walking-Test, ran 10 s faster in the 100-meter time velocity test, and the Forced Vital Capacity stabilized. Growth Differentiation Factor-15 (GDF15) levels, a biomarker of respiratory chain dysfunction, normalized. The only reported side effect was dose-dependent diarrhea.
DISCUSSION
Treatment with dC and dT can significantly improve motor performance and stabilize respiratory function safely in patients with adult-onset TK2d.
Topics: Humans; Male; Thymidine Kinase; Administration, Oral; Adult; Treatment Outcome; Mitochondrial Diseases; Nucleosides
PubMed: 38599303
DOI: 10.1016/j.mito.2024.101879 -
Heliyon Apr 2024Previously, our investigations have underscored the potential of hyperthermia to improve the therapeutic efficacy of gemcitabine (GEM) in pancreatic cancer (PC)....
BACKGROUND
Previously, our investigations have underscored the potential of hyperthermia to improve the therapeutic efficacy of gemcitabine (GEM) in pancreatic cancer (PC). Nonetheless, the precise underlying mechanisms remain elusive.
METHODS
We engineered two GEM-resistant PC cell lines (BxPC-3/GEM and PANC-1/GEM) and treated them with GEM alongside hyperthermia. The impact of hyperthermia on the therapeutic potency of GEM was ascertained through MTT assay, assessment of the concentration of its active metabolite dFdCTP, and evaluation of deoxycytidine kinase (dCK) activity. Lentivirus-mediated dCK silencing was further employed to validate its involvement in mediating the GEM-sensitizing effect of hyperthermia. The mechanism underlying hyperthermia-mediated dCK activation was explored using bioinformatics analyses. The interplay between hyperthermia and the ephrin A4 (EFNA4)/β-catenin/dCK axis was investigated, and their roles in GEM resistance was further explored via the establishment of xenograft tumor models in nude mice.
RESULTS
Hyperthermia restored dCK expression in GEM-resistant cell lines, concurrently enhancing GEM sensitivity and fostering DNA damage and cell death. These observed effects were negated by dCK silencing. Regarding the mechanism, hyperthermia activated dCK by downregulating EFNA4 expression and mitigating β-catenin activation. Overexpression of EFNA4 activated the β-catenin while suppressing dCK, thus diminishing cellular GEM sensitivity-a phenomenon remediated by the β-catenin antagonist MSAB. Consistently, , hyperthermia augmented the therapeutic efficacy of GEM on xenograft tumors through modulation of the ephrin A4/β-catenin/dCK axis.
CONCLUSION
This study delineates the role of hyperthermia in enhancing GEM sensitivity of PC cells, primarily mediated through the suppression of the EFNA4/β-catenin axis and activation of dCK.
PubMed: 38590861
DOI: 10.1016/j.heliyon.2024.e28488 -
ELife Mar 2024Host-directed therapy (HDT) is an emerging approach to overcome antimicrobial resistance in pathogenic microorganisms. Specifically, HDT targets host-encoded factors...
Host-directed therapy (HDT) is an emerging approach to overcome antimicrobial resistance in pathogenic microorganisms. Specifically, HDT targets host-encoded factors required for pathogen replication and survival without interfering with microbial growth or metabolism, thereby eliminating the risk of resistance development. By applying HDT and a drug repurposing approach, we demonstrate that ()-DI-87, a clinical-stage anticancer drug and potent inhibitor of mammalian deoxycytidine kinase (dCK), mitigates abscess formation in organ tissues upon invasive bloodstream infection. Mechanistically, ()-DI-87 shields phagocytes from staphylococcal death-effector deoxyribonucleosides that target dCK and the mammalian purine salvage pathway-apoptosis axis. In this manner, ()-DI-87-mediated protection of immune cells amplifies macrophage infiltration into deep-seated abscesses, a phenomenon coupled with enhanced pathogen control, ameliorated immunopathology, and reduced disease severity. Thus, pharmaceutical blockade of dCK represents an advanced anti-infective intervention strategy against which staphylococci cannot develop resistance and may help to fight fatal infectious diseases in hospitalized patients.
Topics: Animals; Humans; Staphylococcus aureus; Deoxycytidine Kinase; Abscess; Staphylococcal Infections; Anti-Infective Agents; Mammals
PubMed: 38512723
DOI: 10.7554/eLife.91157 -
European Journal of Cancer (Oxford,... Apr 2024The combination of gemcitabine/nab-paclitaxel is an established standard treatment in the first-line treatment of metastatic ductal adenocarcinoma of the pancreas...
PURPOSE
The combination of gemcitabine/nab-paclitaxel is an established standard treatment in the first-line treatment of metastatic ductal adenocarcinoma of the pancreas (mPDAC). Afatinib, an oral second-generation pan ErbB family tyrosine kinase inhibitor, has shown promising pre-clinical signs in the treatment of pancreatic cancer. The aim of this phase 1b trial was to determine the maximum tolerated dose (MTD) of afatinib in combination with gemcitabine/nab-paclitaxel in patients with mPDAC.
METHODS
Treatment naïve patients (≥18 years) with histologically proven mPDAC and good performance status (ECOG 0/1) were enrolled to receive gemcitabine/nab-paclitaxel in combination with afatinib. Treatment was continued until disease progression, or unacceptable toxicity. The primary endpoint MTD was determined using a 3 + 3 design. Treatment started at dose level 0 with intravenous gemcitabine/nab-paclitaxel 1000 mg/m / 125 mg/m (day 1, 8, 15 of a 28-day cycle) + oral afatinib 30 mg daily. At dose level + 1 afatinib was increased to 40 mg. Secondary endpoints included safety parameters and exploratory endpoints evaluated treatment efficacy.
RESULTS
Twelve patients were included in this trial, and 11 patients were treated and analysed in the safety and full analysis set (FAS). At dose level 0 the first three patients did not experience a dose-limiting toxicity (DLT). At dose leve (DL) + 1 two patients experienced a DLT. Accordingly, enrolment continued at DL 0 with three more patients, of which one experienced DLT (skin rash ≥ CTCAE grade 3). Seven patients (63.6%) experienced at least one treatment-emergent serious adverse event (TESAE), with four patients (36.4%) experiencing TESAEs grade 3-5 related to the study medication. In the FAS, the objective response rate (ORR) was 36.4%, median progression-free survival (PFS) was 3.5 months and median overall survival in nine evaluable patients was 7.5 months.
CONCLUSIONS
In this phase 1b clinical trial, the MTD of gemcitabine/nab-paclitaxel (1000 mg/m / 125 mg/m) and afatinib (30 mg) was established. In a cohort of 11 patients, the combination showed an acceptable safety profile.
Topics: Humans; Gemcitabine; Afatinib; Deoxycytidine; Paclitaxel; Albumins; Pancreatic Neoplasms; Treatment Outcome; Antineoplastic Combined Chemotherapy Protocols
PubMed: 38401449
DOI: 10.1016/j.ejca.2024.113926 -
Cell Death & Disease Feb 2024Pancreatic ductal adenocarcinoma (PDAC) is considered one of the most lethal forms of cancer. Although in the last decade, an increase in 5-year patient survival has...
Pancreatic ductal adenocarcinoma (PDAC) is considered one of the most lethal forms of cancer. Although in the last decade, an increase in 5-year patient survival has been observed, the mortality rate remains high. As a first-line treatment for PDAC, gemcitabine alone or in combination (gemcitabine plus paclitaxel) has been used; however, drug resistance to this regimen is a growing issue. In our previous study, we reported MYC/glutamine dependency as a therapeutic target in gemcitabine-resistant PDAC secondary to deoxycytidine kinase (DCK) inactivation. Moreover, enrichment of oxidative phosphorylation (OXPHOS)-associated genes was a common property shared by PDAC cell lines, and patient clinical samples coupled with low DCK expression was also demonstrated, which implicates DCK in cancer metabolism. In this article, we reveal that the expression of most genes encoding mitochondrial complexes is remarkably upregulated in PDAC patients with low DCK expression. The DCK-knockout (DCK KO) CFPAC-1 PDAC cell line model reiterated this observation. Particularly, OXPHOS was functionally enhanced in DCK KO cells as shown by a higher oxygen consumption rate and mitochondrial ATP production. Electron microscopic observations revealed abnormal mitochondrial morphology in DCK KO cells. Furthermore, DCK inactivation exhibited reactive oxygen species (ROS) reduction accompanied with ROS-scavenging gene activation, such as SOD1 and SOD2. SOD2 inhibition in DCK KO cells clearly induced cell growth suppression. In combination with increased anti-apoptotic gene BCL2 expression in DCK KO cells, we finally reveal that venetoclax and a mitochondrial complex I inhibitor are therapeutically efficacious for DCK-inactivated CFPAC-1 cells in in vitro and xenograft models. Hence, our work provides insight into inhibition of mitochondrial metabolism as a novel therapeutic approach to overcome DCK inactivation-mediated gemcitabine resistance in PDAC patient treatment.
Topics: Humans; Carcinoma, Pancreatic Ductal; Cell Line, Tumor; Deoxycytidine; Deoxycytidine Kinase; Drug Resistance, Neoplasm; Gemcitabine; Paclitaxel; Pancreatic Neoplasms; Reactive Oxygen Species
PubMed: 38346958
DOI: 10.1038/s41419-024-06531-x -
Cell Reports Feb 2024Viral mimicry describes the immune response induced by endogenous stimuli such as double-stranded RNA (dsRNA) from endogenous retroelements. Activation of viral mimicry...
Viral mimicry describes the immune response induced by endogenous stimuli such as double-stranded RNA (dsRNA) from endogenous retroelements. Activation of viral mimicry has the potential to kill cancer cells or augment anti-tumor immune responses. Here, we systematically identify mechanisms of viral mimicry adaptation associated with cancer cell dependencies. Among the top hits is the RNA decay protein XRN1 as an essential gene for the survival of a subset of cancer cell lines. XRN1 dependency is mediated by mitochondrial antiviral signaling protein and protein kinase R activation and is associated with higher levels of cytosolic dsRNA, higher levels of a subset of Alus capable of forming dsRNA, and higher interferon-stimulated gene expression, indicating that cells die due to induction of viral mimicry. Furthermore, dsRNA-inducing drugs such as 5-aza-2'-deoxycytidine and palbociclib can generate a synthetic dependency on XRN1 in cells initially resistant to XRN1 knockout. These results indicate that XRN1 is a promising target for future cancer therapeutics.
Topics: Humans; Retroelements; Cell Line; Cytosol; Decitabine; Exonucleases; Neoplasms; RNA, Double-Stranded; Exoribonucleases; Microtubule-Associated Proteins
PubMed: 38261511
DOI: 10.1016/j.celrep.2024.113684