Search Results (263)

Pancreatic cancer (PC) remains a highly lethal malignancy with limited treatment options and poor survival. Targeting DNA damage response (DDR) pathways has emerged as a promising therapeutic strategy, particularly the ATR-CHK1 and ATM-CHK2 axes. Preclinical studies demonstrate that ATR inhibition disrupts replication stress tolerance, impairs homologous recombination, and disables checkpoint control, enhancing cytotoxicity from standard therapies including gemcitabine, FOLFIRINOX, fluoropyrimidines, and radiotherapy. Synergistic effects have also been observed with other DDR-targeted agents, such as PARP and WEE1 inhibitors. Genomic contexts, including ATM deficiency, ARID1A alterations, and oncogene-driven replication stress, refine therapeutic sensitivity, supporting precision patient stratification. Early-phase clinical trials of ATR inhibitors (ART0380, AZD6738, BBI-355) alone or in combination show promising safety, tolerability, and preliminary efficacy. In this review, we summarize current literature on targeting the ATM-CHK2 and ATR-CHK1 pathways in PC, highlighting preclinical evidence, clinical developments, and strategies for biomarker-driven, precision oncology approaches. Full article

Fyn is a Src-family tyrosine kinase implicated in synaptic dysfunction and neuroinflammation across multiple neurodegenerative disorders, including Alzheimer’s disease (AD) and Parkinson’s disease (PD). Saracatinib (AZD0530) is a potent Src-family inhibitor that has been explored as a repurposed therapeutic; however, its clinical utility is limited by poor kinase selectivity caused by high sequence conservation within Src-family ATP-binding sites. Here, we combine surface plasmon resonance (SPR) and X-ray crystallography to define saracatinib recognition by the Fyn kinase domain (KD). SPR single-cycle kinetics shows that saracatinib binds the isolated Fyn KD and full-length Fyn with low-nanomolar affinity, whereas dasatinib binds with subnanomolar affinity and markedly slower dissociation. We determined the crystal structure of the Fyn KD-saracatinib complex at 2.22 Å resolution. The kinase adopts an active-like conformation with the DFG motif and αC-helix in the ‘in’ state and a conserved β3 αC Lys-Glu salt bridge. Saracatinib occupies the adenine and ribose pockets, and engages the hinge through direct and water-mediated hydrogen bonding while complementing a hydrophobic back pocket by van der Waals contacts. Comparison with reported saracatinib-bound structures of other kinases suggests that the active-state geometry observed for Fyn creates a pocket not observed in inactive-like complexes, providing a structural handle for designing Fyn-selective inhibitors. Comparison with all saracatinib-bound kinase co-structures currently available in the PDB (ALK2 and PKMYT1) indicates a conserved monodentate hinge binding mode but kinase-dependent αC-helix conformations, providing a structural rationale for designing Fyn-selective analogues. Full article

Background/Objectives: Approved for treatment of acute leukemia, gemtuzumab ozogamicin (GO) and inotuzumab ozogamicin (InO) are antibody–drug conjugates (ADCs) that deliver a toxic calicheamicin (CLM) derivative. The resistance mechanisms to GO/InO remain incompletely understood. Methods: We performed a genome-wide clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9 screen for CLM sensitivity genes, and then performed confirmatory cytotoxicity assays. Results: Several DNA damage pathway regulation genes were identified, most notably TP53. Across 13 acute leukemia cell lines, the six TP53-mutant cell lines (TP53^MUT) were indeed 10- to 1000-fold less sensitive to CLM than the seven TP53^WT cell lines. In five TP53^WT/KO syngeneic cell line pairs we generated, TP53^KO cells were significantly less sensitive to CLM than their TP53^WT counterparts. In TP53^WT but not TP53^MUT cells, the MDM2 inhibitor and p53 activator, idasanutlin, enhanced CLM cytotoxicity, demonstrating that decoupling of cells from MDM2-p53 regulation sensitizes leukemia cells to CLM. The ATM inhibitors AZD1390 and lartesertib also significantly enhanced CLM efficacy but did so independent of the TP53 status. In contrast, neither an ATR inhibitor, Chk1/Chk2 inhibitor, Chk2 inhibitor, or a PARP inhibitor significantly impacted CLM-induced cytotoxicity across the thirteen cell lines. Together, our studies identify ATM, MDM2, and TP53—which are in the same cellular response to DNA damage pathway—as key modulators of CLM-induced cytotoxicity in acute leukemia cells. Conclusions: These results support further evaluation of combination therapies with corresponding small-molecule inhibitors (currently pursued for therapy of other cancers) toward clinical testing as novel strategies to increase the efficacy of CLM-based ADCs such as GO and InO. Full article

Cathepsin C (CTSC) mediates neutrophil serine protease (NSP) maturation, contributing to inflammatory cascades, making it a key therapeutic target. In this study, through large-scale screening of a natural product library, marrubiin, a diterpenoid lactone compound, was identified as a potent CTSC inhibitor, which holds potential value in the treatment of inflammatory diseases. It inhibited human recombinant CTSC (IC₅₀ = 57.5 nM) and intracellular CTSC (IC₅₀ = 51.6 nM) with acceptable cytotoxicity, and reduced the activity and protein levels of downstream NSPs in vitro. Functionally, marrubiin inhibited lipopolysaccharide-induced nitric oxide release and regulated the levels of cytokines and chemokines. Docking result predicted marrubiin may achieve CTSC activity inhibition by using lactone structure as a covalent unit to target Cys234. In vivo study indicated that high-dose marrubiin (IC₅₀ = 30 mg/kg) reduced CTSC and NSPs activities in blood and bone marrow in mice without toxicity, and its efficacy was comparable to that of positive compound AZD7986. In the adjuvant-induced arthritis model, high-dose marrubiin (IC₅₀ = 60 mg/kg) exerted a therapeutic effect by reducing the activities of CTSC and NSPs. These findings indicated marrubiin is a promising natural CTSC inhibitor, which can be used for the treatment of neutrophil-related inflammatory diseases. Full article

Enhancer RNAs (eRNAs) are abundant in most human cells and tissues, and quantifying eRNAs has become a robust approach for biomarker discovery. While eRNAs play crucial roles in regulating biological processes and cancer progression, their functions in lung adenocarcinoma (LUAD) remain poorly understood. Here, we developed a LUAD prognostic model based on eRNA expression data from The Cancer Genome Atlas (TCGA). Through rigorous validation, a 7-eRNA signature was identified, which robustly stratified LUAD patients into high-risk and low-risk groups in both training and testing sets. Functional analyses revealed distinct enrichment of pathways related to amino acid biosynthesis, ribosome biogenesis, and proteasome activity in high-risk patients. Somatic mutation profiling highlighted TP53 and TTN as frequently mutated genes, while drug sensitivity prediction identified four potential therapeutic agents (including AZD4547 and Nutlin-3a) for high-risk individuals. Collectively, this study constructed a 7-eRNA prognostic model for LUAD, providing a powerful tool for clinical risk assessment and uncovering eRNA-mediated regulatory mechanisms. Full article

Peritoneal carcinomatosis (PC) is a late-stage manifestation of abdominopelvic malignancies with poor prognosis and limited treatment options. Unique biochemical mechanisms within the peritoneal cavity play a key role in disease progression and resistance to therapy. Despite current therapies like systemic chemotherapy and cytoreductive surgery, patients frequently develop severe complications, including bowel obstruction, nutritional decline, and ascites, driving the need to address the pro-tumorigenic niche in the peritoneal cavity. The immune microenvironment in PC is marked by elevated proinflammatory mediators, such as IL-6 and IL-8, which skew the response toward innate rather than adaptive immune responses. IL-8 signaling, through its receptors CXCR1 and CXCR2, promotes neutrophil recruitment, chronic inflammation, angiogenesis, epithelial–mesenchymal transition, and immune evasion, making the IL-8/CXCR1/CXCR2 axis a potential therapeutic target in PC. Pre-clinical models provide evidence that IL-8 or CXCR1/CXCR2 blockade may be a valuable therapeutic strategy. IL-8 targeting agents such as monoclonal antibodies (BMS-986253) and small-molecule inhibitors (SX-682, AZD5069, navarixin) have shown efficacy in mitigating tumor growth and improving the efficacy of immune checkpoint inhibitors. Phase I and II trials have demonstrated encouraging safety profiles and preliminary efficacy when treating multiple abdominopelvic malignancies. In this review, we discuss the influence of the IL-8/CXCR1/CXCR2 axis within the peritoneal immune environment in PC and highlight recent work using IL-8 or CXCR1/CXCR2 blockade as a therapeutic strategy for PC. Continued research into the peritoneal immune microenvironment and the development of targeted therapies are essential for improving the management and prognosis of PC, potentially enhancing antitumor immunity and patient outcomes. Full article

Background/Objectives: Colorectal cancer (CRC) remains a significant global health concern, with limited treatment options for metastatic stage 4 CRC. Fibroblast Growth Factor Receptor (FGFR) is a promising therapeutic target in CRC, while cannabidiol (CBD) has shown potential for inducing cell death and overcoming drug resistance. This study evaluates the efficacy of FGFR inhibitors and explores the synergistic effects of combining FGFR inhibitors with CBD in inducing apoptosis in CRC cells. Methods: Cannabidiol and FGFR inhibitors were applied, and protein expression was analyzed via Western blot. Cell viability was assessed using the WST-1 assay, while apoptosis was measured through flow cytometry using Annexin V-FITC/PI staining. CHOP-specific siRNA transfection was performed to study gene silencing effects, followed by RNA sequencing for differential expression and pathway analysis. Statistical significance was determined using ANOVA and t-tests, with p < 0.05. Results: FGFR expression patterns were confirmed in various cancer cell lines, with NCI-H716 showing high FGFR2 expression. Treatment with CBD (4 µM) and AZD4547 (10 nM) resulted in significant cell death, especially when used in combination, indicating the effectiveness of this combined therapy. Increased apoptosis in NCI-H716 cells was confirmed with the combined treatment. RNA sequencing and heatmap analysis suggested that ER stress might be related to the observed synergistic effect. The role of ER stress in the combination-induced apoptosis of NCI-H716 cells was further validated. Conclusions: The combination of FGFR inhibitors and cannabidiol exhibited a synergistic effect in inducing cell death in colorectal cancer cells, likely through the ER stress pathway. This study supports the potential of combined FGFR inhibitor and CBD therapy as a promising strategy for enhancing anticancer effects in CRC. Full article

Background: The treatment landscape for multiple myeloma (MM) has significantly evolved in recent decades with novel therapies like proteasome inhibitors, immunomodulatory drugs and monoclonal antibodies. However, MM remains incurable, necessitating new pharmacological strategies. Mitotic kinases, such as Aurora proteins, have emerged as potential targets. Selective inhibitors of Aurora A and B,- alisertib (MLN8237) and barasertib (AZD1152), respectively, have shown anti-myeloma activity in preclinical studies, with alisertib demonstrating modest efficacy in early clinical trials. Methods and Results: This study investigated the mechanisms of action of alisertib and barasertib and their combination with antitumor agents in a panel of five MM cells lines. Both drugs induced cell cycle arrest phase and abnormal nuclear morphologies. Alisertib caused prolonged mitotic arrest, whereas barasertib induced transient arrest, both resulting in the activation of mitotic catastrophe. These findings revealed three potential outcomes: cell death, senescence, or polyploidy. High mitochondrial reactive oxygen species (mROS) were identified as possible drivers of cell death. Caspase inhibition reduced caspase-3 activation but did not prevent cell death. Interestingly, alisertib at low doses remained toxic to Bax/Bak^DKO cells, although mitochondrial potential disruption and cytochrome c release were observed. Sequential combinations of high-dose Aurora kinase inhibitors with BH3-mimetics, and in specific cases with panobinostat, showed a synergistic effect. Conversely, the simultaneous combination of alisertib and barasertib showed mostly antagonistic effects. Conclusions: Alisertib and barasertib emerge as potential in vitro candidates against MM, although further studies are needed to validate their efficacy and to find the best combinations with other molecules. Full article

Background: Esophageal squamous cell carcinoma (ESCC) is a fatal malignant tumor. Several studies have demonstrated that immune checkpoint inhibitors can provide clinical benefits to patients with ESCC. However, the single-agent efficacy of these agents remains limited. Although combination therapies (e.g., radiotherapy, chemotherapy) can help to overcome immunotherapy resistance in ESCC, their severe side effects limit clinical application. This study aimed to explore new resistance mechanisms to immunotherapy in ESCC and identify novel molecular targets to overcome immunotherapy resistance. Methods: We employed immunohistochemistry staining to examine the p-FGFR1^Y654 in tumor samples obtained from 103 patients with ESCC, in addition to evaluating CD8+ T cell infiltration. In vitro expression, western blotting, CCK-8, 5-bromo-2′-deoxyuridine incorporation assays, and migration assays were used to confirm the impact of AZD4547 on p-FGFR1^Y654 expression and the proliferation and migration in ESCC cell lines. Through RNA sequencing analysis, databases such as the Cancer Genome Atlas (TCGA) and Gene Set Cancer Analysis (GSCA), and the reconstruction of transgenic mice using the humanized immune system, we validated the correlation between the expression of p-FGFR1^Y654 and CD8+ T cell infiltration. We also explored how p-FGFR1^Y654 recruits myeloid-derived suppressor cells (MDSCs) through the CXCL8–CXCR2 axis to suppress the therapeutic efficacy of immunotherapy in ESCC. Finally, the tumor-suppressive effects of AZD4547 combined with immunotherapy were confirmed in vivo in tumor-bearing mice with a humanized immune system. Results: We found that the inhibition of p-FGFR1^Y654 expression in ESCC can enhance CD8+ T cell infiltration by suppressing the CXCL8-–XCR2 recruitment of MDSCs. AZD4547, combined with immunotherapy, further promotes immunotherapeutic efficacy in ESCC. Conclusions: In conclusion, our study presents a promising model for combination therapy in ESCC immunotherapy. Full article

Parkinson’s disease (PD) is a progressive neurodegenerative disorder marked by the degeneration of dopaminergic neurons in the substantia nigra, leading to decreased dopamine levels in the striatum and causing a range of motor and non-motor impairments. Although the molecular mechanisms driving PD progression remain incompletely understood, emerging evidence suggests that the buildup of nuclear DNA damage, especially DNA double-strand breaks (DDSBs), plays a key role in contributing neurodegeneration, promoting senescence and neuroinflammation. Despite the pathogenic role for DDSB in neurodegenerative disease, targeting DNA repair mechanisms in PD is largely unexplored as a therapeutic approach. Ataxia telangiectasia mutated (ATM), a key kinase in the DNA damage response (DDR), plays a crucial role in neurodegeneration. In this study, we evaluated the therapeutic potential of AZD1390, a highly selective and brain-penetrant ATM inhibitor, in reducing neuroinflammation and improving behavioral outcomes in a mouse model of α-synucleinopathy. Four-month-old C57BL/6J mice were unilaterally injected with either an empty AAV1/2 vector (control) or AAV1/2 expressing human A53T α-synuclein to the substantia nigra, followed by daily AZD1390 treatment for six weeks. In AZD1390-treated α-synuclein mice, we observed a significant reduction in the protein level of γ-H2AX, a DDSB marker, along with downregulation of senescence-associated markers, such as p53, Cdkn1a, and NF-κB, suggesting improved genomic integrity and attenuation of cellular senescence, indicating enhanced genomic stability and reduced cellular aging. AZD1390 also significantly dampened neuroinflammatory responses, evidenced by decreased expression of key pro-inflammatory cytokines and chemokines. Interestingly, mice treated with AZD1390 showed significant improvements in behavioral asymmetry and motor deficits, indicating functional recovery. Overall, these results suggest that targeting the DDR via ATM inhibition reduces genotoxic stress, suppresses neuroinflammation, and improves behavioral outcomes in a mouse model of α-synucleinopathy. These findings underscore the therapeutic potential of DDR modulation in PD and related synucleinopathy. Full article

Background/Objectives: Primary pulmonary carcinoma (PC) is a malignant neoplasm that occurs in humans, dogs, and other species. In canine PC, palliative care remains the most practical approach for dogs with inoperable PC. Methods: We investigated the effectiveness of mammalian target of rapamycin (mTOR) inhibitors in canine lung cancer upon PI3K/AKT/mTOR activation. Three canine PC cell lines (AZACL1, AZACL2, and cPAC-1) were treated with three mTOR inhibitors (AZD8055, temsirolimus, and everolimus). In vitro, sensitivity assays were conducted to evaluate proliferation and Western blotting was used to examine pathway activation and phosphorylation of mTOR-related protein. Results: AZD8055 had a stronger inhibitory effect on cell proliferation than temsirolimus and everolimus in all three PC cell lines. The IC₅₀ for AZD8055 in the AZACL1, AZACL2, and cPAC-1 cell lines were 23.8 μM, 95.8 nM, and 237 nM, for temsirolimus they were 34.6 μM, 11.5 μM, and 11.2 μM, and for everolims they were 36.6 μM, 33.4 μM, and 33.0 μM, respectively. Western blotting revealed PI3K/AKT/mTOR pathway activation and differential phosphorylation of mTOR signal-related proteins across the three PC cell lines. In xenograft mice injected with the AZACL1 and AZACL2 cell lines we showed that the AZD8055-treated group exhibited a significant reduction in tumor volume via the inhibition of tumor growth compared to the control group. Conclusions: These findings reveal that the PI3K/AKT/mTOR pathway plays a key role in canine PC and that AZD8055 may be a novel therapeutic agent for PC-bearing dogs. Full article

Small-molecule glucagon-like peptide-1 receptor agonists (GLP-1RAs) represent an innovative advancement in oral therapeutics, addressing key limitations associated with injectable peptide-based incretin therapies. These nonpeptidic agents exert their actions primarily through non-canonical binding orthosteric sites within the GLP-1 receptor transmembrane domain, enabling selective G protein (Gs)-biased signaling with reduced β-arrestin-mediated adverse effects. Orforglipron has notably advanced through Phase 3 clinical development, demonstrating significant reductions in hemoglobin A1c and body weight (up to 7.9%) with favorable tolerability. Conversely, promising candidates such as danuglipron and lotiglipron were discontinued due to hepatotoxicity, underscoring critical safety concerns intrinsic to small-molecule GLP-1RA development. Current clinical candidates, including GSBR-1290, CT-996, and ECC5004, continue to offer substantial potential due to their oral bioavailability, simplified dosing regimens, and favorable gastrointestinal tolerability. Nevertheless, challenges persist regarding hepatic safety, pharmacodynamic variability, and limited long-term outcome data. This review integrates current structural, pharmacological, and clinical evidence, highlights key mechanistic innovations—including biased agonism, covalent binding strategies, and allosteric modulation—and discusses future directions for this rapidly evolving therapeutic class in metabolic disease management. Full article

Cancer cell spheroids autonomously form in the ascites fluid and are considered a conduit for epithelial ovarian cancer metastasis within the peritoneal cavity. Spheroids are homotypic, avascular 3D structures that acquire resistance to anoikis to remain viable after cellular detachment. We used in vitro spheroid model systems to interrogate pathways critical for spheroid cell proliferation, distinct from those driving monolayer cancer cell proliferation. Using the 105C and KOC-7c human ovarian clear cell carcinoma (OCCC) cell lines, which have distinct proliferative phenotypes as spheroids but the same prototypical OCCC gene mutation profile of constitutively activated AKT signaling with the loss of ARID1A, we revealed therapeutic targets that efficiently kill cells in spheroids. RNA-seq analyses compared the transcriptome of 3-day monolayer and spheroid cells from these lines and identified the characteristics of dormant spheroid cell survival, which included the G2/M checkpoint, autophagy, and other stress pathways induced in 105C spheroids, in sharp contrast to the proliferating spheroid cells of the KOC-7c cell line. Next, we assessed levels of various G2/M checkpoint regulators and found a consistent reduction in steady-state levels of checkpoint regulators in dormant spheroid cells, but not proliferative spheroids. Our studies showed that proliferative spheroid cells were sensitive to Wee1 inhibition by AZD1775, but the dormant spheroid cells showed a degree of resistance to AZD1775, both in terms of EC50 values and spheroid reattachment abilities. Thus, we identified biomarkers of dormant spheroids, including the G2/M checkpoint regulators Wee1, Cdc25c, and PLK1, and showed that, when compared to proliferating spheroid cells, the transcriptome of dormant OCCC spheroids is a source of therapeutic targets. Full article

Background: The effectiveness of COVID-19 vaccines appears to decline rapidly over time due to waning immunity and immune evasion by emerging variants of concern, and may be reduced in high-risk populations. We aimed to evaluate the rates of SARS-CoV-2 breakthrough infection or severe COVID-19, both in individuals who had completed their primary COVID-19 vaccination, and in those who had received their first booster vaccination. Specifically, we aimed to evaluate whether persons with certain risk factors, such as age, gender, socioeconomic status (SES), and specified comorbidities have an increased risk of either breakthrough infection or severe COVID-19, compared to those without the respective risk factors. Methods: Data on COVID-19 vaccinations, infections, hospitalizations, and deaths were collected from the PHARMO Data Network, consisting of health records from Dutch residents. Two cohorts were established: (1) all persons who have completed their primary COVID-19 vaccination regimen, and (2) those who have received their first booster vaccination. The outcomes were SARS-CoV-2 breakthrough infection, and severe COVID-19, defined as either hospitalization or death following SARS-CoV-2 infection. Incidence rates of these outcomes were calculated in both cohorts. The adjusted incidence rate ratios of these outcomes in persons with certain risk factors were calculated, using generalized linear models with a Poisson distribution. Results: In 2021, a total of 1,090,567 individuals received either two doses of BNT162b2, AZD1222, or mRNA-1273, or one dose of Ad26.COV2.S and were included in the primary vaccination cohort, of which 344,153 (31.6%) received a booster vaccination. Overall incidence rates of SARS-CoV-2 breakthrough infection and severe COVID-19 after primary vaccination were 29.9 and 3.1 per 1000 person-years, respectively, and after booster vaccination were 256.4 and 2.3, respectively. Male gender, older age, lower SES, history of COVID-19, and recent hospitalization were factors associated with a lower risk of breakthrough infection after primary vaccination, and a higher risk of severe COVID-19. The risk of severe COVID-19 after primary vaccination was increased in persons with several comorbidities, compared to those without, and remained elevated after booster vaccination in persons with diabetes or lung disease. Conclusions: Our study emphasizes the crucial role of boosters in reducing breakthrough infections, particularly in high-risk populations. The varied impact on severe outcomes in individuals with comorbidities underscores the need for ongoing surveillance and tailored vaccination strategies. Full article

CXCL1 (Gro-α, MGSA) is a chemokine functionally similar to CXCL8/IL-8, as both activate the same receptor, CXCR2. CXCL1 levels are frequently elevated in tumors compared to healthy tissue, where they play a key role in promoting cancer cell migration, angiogenesis, and neutrophil recruitment. While the involvement of CXCL1 in tumor progression is well established, its relevance to cancer therapy remains underexplored. This review examines the therapeutic potential of targeting CXCL1 and its receptor, CXCR2, in cancer treatment. It discusses anti-CXCL1 antibodies and CXCR2 antagonists, including AZD5069, SB225002, SCH-479833, navarixin/SCH-527123, ladarixin/DF2156A, and reparixin, as well as strategies to enhance CXCR2 expression in lymphocytes during adoptive cell therapy to improve immunotherapy outcomes. Particular attention is given to the role of CXCL1 in treatment resistance, including resistance to chemotherapy, radiotherapy, and anti-angiogenic therapy. Cancer therapies often upregulate CXCL1 expression, which in turn drives treatment resistance. Additionally, this review explores the contribution of CXCL1 to therapy-induced side effects, such as chemotherapy-induced metastasis, neuropathy, nephrotoxicity, diarrhea, and cardiotoxicity. CXCR2 inhibitors are well tolerated by patients in clinical trials. However, the limited number of studies evaluating these agents in combination with standard chemotherapy precludes any definitive conclusions. Full article