Phase II Study of Ulixertinib in Children and Young Adults With Tumors Harboring Activating Mitogen-Activated Protein Kinase Pathway Alterations: APEC1621J of the National Cancer Institute-Children's Oncology Group Pediatric MATCH Trial.

PURPOSE: The National Cancer Institute-Children's Oncology Group (NCI-COG) Pediatric MATCH trial assigns patients age 1-21 years with refractory malignancies to phase II treatment arms of molecularly targeted therapies on the basis of genetic alterations detected in their tumor. Patients with activating alterations in the mitogen-activated protein kinase pathway were treated with ulixertinib, an extracellular signal-regulated kinase (ERK)1/2 inhibitor. METHODS: As there were no previous pediatric data, ulixertinib was initially tested in a dose escalation cohort to establish the recommended phase II dose (RP2D) before proceeding to the phase II cohort. Ulixertinib was administered at 260 mg/m2/dose orally twice a day (dose level 1 [DL1], n = 15) or 350 mg/m2/dose orally twice a day (DL2, n = 5). The primary end point was objective response rate; secondary end points included safety/tolerability and progression-free survival (PFS). RESULTS: Twenty patients (median 12 years; range, 5-20) were treated, all evaluable for response. CNS tumors comprised 55% (11/20) of diagnoses, with high-grade glioma and low-grade glioma most common (n = 5 each). All CNS tumors except one harbored BRAF fusions or V600E mutations. Rhabdomyosarcoma (n = 5) was the most frequent non-CNS diagnosis. DL1 was declared the RP2D in the dose escalation cohort after dose-limiting toxicities in Cycle 1 occurred in 1/6 patients at DL1 and 2/5 patients at DL2, including fatigue, anorexia, rash, nausea, vomiting, diarrhea, dehydration, hypoalbuminemia, and hypernatremia. No objective responses were observed. Six-month PFS was 37% (95% CI, 17 to 58). Three patients with BRAF-altered CNS tumors achieved stable disease >6 months. CONCLUSION: Ulixertinib, a novel targeted agent with no previous pediatric data, was successfully evaluated in a national precision medicine basket trial. The pediatric RP2D of ulixertinib is 260 mg/m2/dose orally twice a day. Limited single-agent efficacy was observed in a biomarker-selected cohort of refractory pediatric tumors.

Lumacaftor as a potential repurposed drug in targeting breast cancer stem cells: insights from in silico study.

CONTEXT: Breast cancer stem cells (BCSCs) are a small subset of cells within breast tumors with characteristics similar to normal stem cells. Despite advancements in chemotherapy and targeted therapy for breast cancer, the prognosis for breast cancer patients has remained poor due to drug resistance, reoccurrence, and metastasis. Growing evidence suggests that deregulation of the self-renewal pathways, like the Wnt signaling pathway mediated by ß-catenin, plays a crucial role in the survival of breast cancer stem cells. Targeting the Wnt signaling pathway in breast cancer stem cells offers a promising avenue for developing effective therapeutic strategies targeting these cells, potentially leading to improved patient outcomes and reduced tumor recurrence. METHODS: For this purpose, we have screened a 1615 FDA-approved drug library against our target protein, ß-catenin, which is involved in the Wnt signaling pathway using molecular docking analysis, molecular dynamics (MD) simulations, and molecular mechanics Poisson-Boltzmann surface area (MM/PBSA) calculations. RESULTS: Molecular docking studies showed that the Lumacaftor- ß-catenin complex had the lowest docking score of - 8.7 kcal/mol towards ß-catenin protein than the reference inhibitor. Molecular dynamic simulations and MM/PBSA calculations were also performed for the Lumacaftor-ß-catenin complex to establish the stability of the interactions involved. Considering its promising attributes and encouraging results, Lumacaftor holds significant potential as a novel therapeutic option to target BCSCs. This study opens avenues for further investigation and may pave the way for developing therapeutic potential in breast cancer treatment. Further confirmation is warranted through in vitro and clinical studies to validate the findings of this study.

Synthesis of novel aryl-substituted 2-aminopyridine derivatives by the cascade reaction of 1,1-enediamines with vinamidinium salts to develop novel anti-Alzheimer agents.

Alzheimer's disease (AD), a severe neurodegenerative disorder, imposes socioeconomic burdens and necessitates innovative therapeutic strategies. Current therapeutic interventions are limited and underscore the need for novel inhibitors of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), enzymes implicated in the pathogenesis of AD. In this study, we report a novel synthetic strategy for the generation of 2-aminopyridine derivatives via a two-component reaction converging aryl vinamidinium salts with 1,1-enediamines (EDAMs) in a dimethyl sulfoxide (DMSO) solvent system, catalyzed by triethylamine (Et3N). The protocol introduces a rapid, efficient, and scalable synthetic pathway, achieving good to excellent yields while maintaining simplistic workup procedures. Seventeen derivatives were synthesized and subsequently screened for their inhibitory activity against AChE and BChE. The most potent derivative, 3m, exhibited an IC50 value of 34.81 ± 3.71 µM against AChE and 20.66 ± 1.01 µM against BChE compared to positive control donepezil with an IC50 value of 0.079 ± 0.05 µM against AChE and 10.6 ± 2.1 µM against BChE. Also, detailed kinetic studies were undertaken to elucidate their modes of enzymatic inhibition of the most potent compounds against both AChE and BChE. The promising compound was then subjected to molecular docking and dynamics simulations, revealing significant binding affinities and favorable interaction profiles against AChE and BChE. The in silico ADMET assessments further determined the drug-like properties of 3m, suggesting it as a promising candidate for further pre-clinical development.

Clinical treatment patterns, molecular characteristics and survival outcomes of ROS1-rearranged non-small cell lung cancer: A large multicenter retrospective study.

BACKGROUND: Non-small cell lung cancer (NSCLC) harboring ROS1 rearrangements is a molecular subset that exhibits favorable responses to tyrosine kinase inhibitor (TKI) treatment than chemotherapy. This study investigated real-world treatment patterns and survival outcomes among patients with ROS1-rearranged advanced NSCLC. METHODS: We conducted a retrospective analysis of patients with ROS1-rearranged advanced NSCLC treated in four different hospitals in China from August 2018 to March 2022. The study analyzed gene fusion distribution, resistance patterns, and survival outcomes. RESULTS: ROS1 rearrangement occurs in 1.8 % (550/31,225) of our study cohort. CD74 was the most common ROS1 fusion partner, accounting for 45.8 %. Crizotinib was used in 73.9 % of patients in the first-line treatment, and an increased use of chemotherapy, ceritinib, and lorlatinib was seen in the second-line setting. Lung (43.2 %) and brain (27.6 %) were the most common sites of progression in first-line setting, while brain progression (39.2 %) was the most common site of progression in second-line. Median overall survival was 46 months (95 % confidence intervals: 39.6-52.4). First-line crizotinib use yielded significantly superior survival outcomes over chemotherapy in terms of progression-free (18.5 vs. 6.0; p < 0.001) and overall survival (49.8 vs. 37; p = 0.024). The choice of treatment in the latter line also had survival implications, wherein survival outcomes were better when first-line crizotinib was followed by sequential TKI therapy than first-line chemotherapy followed by TKI therapy. CONCLUSIONS: Our study provided insights into the real-world treatment, drug resistance patterns, and survival outcomes among patients with ROS1-rearranged NSCLC. This information serves as a valuable reference for guiding the treatment of this molecular subset of NSCLC.

Long-term therapy with CFTR modulators consistently improves glucose metabolism in adolescents and adults with cystic fibrosis.

BACKGROUND: Impaired glycemic control and the subsequent development of Cystic fibrosis Related Diabetes (CFRD) are prevalent complications, affecting up to 50 % of adults with cystic fibrosis (CF). CFTR modulator (CFTRm) therapies improve pulmonary functions, reduce exacerbation rates, increase survival in people with CF (pwCF) and appear to have a positive effect on extrapulmonary manifestations, such as nutritional state, improvements in upper respiratory symptoms, and quality of life. Initial findings indicate that CFTRm may have a positive impact on short-term glycemic control; however, long-term effects remain uncertain at present. METHODS: In this retrospective study, data were collected and analyzed on 15 pwCF, ages 13-37 years, started on CFTRm therapy. Oral Glucose Tolerance Test (OGTT) results were compared pre- and post-CFTRm therapy. RESULTS: The 120-min OGTT value decreased from 159.7 mg/dL to 130.4 mg/dL post-CFTRm (p = 0.047). The average time elapsed between the two OGTTs was 49.87 months (ranging 9-157 months, median 38 months). Glycemic status improved in six pwCF (two CFRD to normal (NGT)/indeterminate (INDET) glucose tolerance; two impaired glucose tolerance (IGT) to INDET; two INDET to NGT) and worsened in one (IGT to CFRD). Six pwCF and NGT remained stable with no changes in glycemic status throughout the follow-up period. CONCLUSIONS: CFTRm therapy may decelerate the glycemic control deterioration in pwCF over an extended period. These findings indicate the need for periodic OGTTs following the initiation of CFTRm therapy to appropriately adjust insulin requirements and prevent hypoglycemia. Further larger cohorts are required to authenticate and substantiate these findings.

Roflumilast ameliorates GAN diet-induced non-alcoholic fatty liver disease by reducing hepatic steatosis and fibrosis in ob/ob mice.

Non-alcoholic fatty liver disease (NAFLD) is a highly prevalent progressive liver disease. Currently, there is only one drug for NAFLD treatment, and the options are limited. Phosphodiesterase-4 (PDE-4) inhibitors have potential in treating NAFLD. Therefore, this study aims to investigate the effect of roflumilast on NAFLD. Here, we fed ob/ob mice to induce the NAFLD model by GAN diet. Roflumilast (1 mg/kg) was administered orally once daily. Semaglutide (20 nmol/kg), used as a positive control, was injected subcutaneously once daily. Our findings showed that roflumilast has beneficial effects on NAFLD. Roflumilast prevented body weight gain and improved lipid metabolism in ob/ob-GAN NAFLD mice. In addition, roflumilast decreased hepatic steatosis by down-regulating the expression of hepatic fatty acid synthesis genes (SREBP1c, FASN, and CD36) and improving oxidative stress. Roflumilast not only reduced liver injury by decreasing serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, but also ameliorated hepatic inflammation by reducing the gene expression of proinflammatory cytokines (TNF-α, IL-1ß, and IL-6). Roflumilast lessened liver fibrosis by inhibiting the expression of fibrosis mRNA (TGFß1, α-SMA, COL1a1, and TIMP-1). Collectively, roflumilast could ameliorate NAFLD, especially in reducing hepatic steatosis and fibrosis. Our findings suggested a PDE-4 inhibitor roflumilast could be a potential drug for NAFLD.

EGFR and HER2 hyper-activation mediates resistance to endocrine therapy and CDK4/6 inhibitors in ER+ breast cancer.

In patients with ER + metastatic breast cancer (mBC), the first-line treatment involves the combination of endocrine therapy (ET) and CDK4/6 inhibitors (CDK4/6i). However, a significant group of patients experiences disease progression, emphasizing the urgent clinical need to identify novel anti-tumor therapies. We previously generated breast cancer cells resistant to the combination of fulvestrant (ER downregulator) and abemaciclib (CDK4/6 inhibitor) from MCF7 and T47D (MCF7-FAR and T47D-FAR). RNA-seq-based Gene Set Enrichment Analysis (GSEA) revealed hyper-activation of EGFR, HER2, and AKT signaling in both MCF7-FAR and T47D-FAR. Modulating EGFR or ERBB2 expression through loss- and gain-of-function experiments altered tumor sensitivity to fulvestrant and abemaciclib in parental and FAR spheroids, affecting ERK and AKT/S6 pathways. Cetuximab treatment overcame tumor resistance to fulvestrant and abemaciclib in FAR and EGFR-overexpressing breast cancer spheroids and xenografts. Likewise, patient-derived organoids (PDOs) from individuals with ER + mBC, progressing on palbociclib, exhibited up-regulation of EGFR and HER2 pathways. In conclusion, our findings suggest that inhibiting EGFR and HER2 pathways might overcome resistance to ET + CDK4/6i in selected patients with ER + mBC.

Efficacy and safety of flumatinib in the treatment of newly diagnosed chronic myeloid leukemia in the chronic phase: A real-world single-center retrospective study, with a focus on premature drug discontinuation.

PURPOSE: To assess the real-world efficacy and safety of flumatinib as first-line and post-line treatments for chronic myeloid leukemia in the chronic phase (CML-CP). RESULTS: Among 141 patients receiving flumatinib as first-line and post-line treatment, the 12-month major molecular response (MMR) rates were 69.4% and 67.6%, respectively. The median time to response was 6 and 10.5 months, respectively. In post-line treatment, the early molecular response (EMR) of flumatinib as second-line is significantly superior to that of third-line treatment (3-month EMR rate: 79.2% vs. 39.3%, P<0.001; 3-month MMR rate: 45.8% vs. 21.4%, P=0.033). Contrastively, patients who switched to flumatinib due to intolerance had significantly higher MMR rates at 3, 6, and 12 months compared to patients who switched due to inadequate response (60.6% vs. 24.2%, P=0.003; 66.7% vs. 36.0%, P=0.027; 84.2% vs. 50.0%, P=0.038). Premature drug discontinuation was observed in 28.4% of the patients. Grades 3-4 hematologic adverse events (AEs) were identified as independent risk factors for premature drug discontinuation. Patients who discontinued treatment and those who previously received only imatinib therapy had a poorer molecular response and failure-free survival. CONCLUSIONS: Flumatinib demonstrates favorable efficacy and safety. Treatment discontinuation can result in a poorer molecular response and long-term prognosis.

CDK4/6 inhibitors: The Devil is in the Detail.

PURPOSE OF REVIEW: Update on the most recent clinical evidence on CDK4/6 inhibitors (CDK4/6i) in the treatment of hormone receptor (HR)-positive, human epidermal growth factor receptor (HER)2-negative breast cancer. RECENT FINDINGS: Over the past decade, CDK4/6i have become part of the standard of care treatment of patients with both metastatic and high-risk early HR + /HER2- breast cancers. The three available CDK4/6i (palbociclib, ribociclib and abemaciclib) have been extensively studied in combination with endocrine therapy (ET) in metastatic breast cancer (mBC) with consistent prolongation of progression free survival; however, ribociclib has emerged as the preferred first line agent in mBC given overall survival benefit over endocrine monotherapy. In early BC, abemaciclib is the only currently approved agent while ribociclib has early positive clinical trial data. Toxicities and financial burden limit the use of CDK4/6i in all patients and resource-poor settings, and optimal timing of their use in mBC remains unclear. There is considerable evidence for the use of CDK4/6i in metastatic and early HR + /HER2- breast cancer, but knowledge gaps remain, and further research is necessary to better define their optimal use.

Sintilimab (anti-PD-1 antibody) plus chidamide (histone deacetylase inhibitor) in relapsed or refractory extranodal natural killer T-cell lymphoma (SCENT): a phase Ib/II study.

Anti-PD-1 antibodies are a favorable treatment for relapsed or refractory extranodal natural killer T cell lymphoma (RR-ENKTL), however, the complete response (CR) rate and the duration of response (DOR) need to be improved. This phase 1b/2 study investigated the safety and efficacy of sintilimab, a fully human anti-PD-1 antibody, plus chidamide, an oral subtype-selective histone deacetylase inhibitor in 38 patients with RR-ENKTL. Expected objective response rate (ORR) of combination treatment was 80%. Patients received escalating doses of chidamide, administered concomitantly with fixed-dose sintilimab in 21-days cycles up to 12 months. No dose-limiting events were observed, RP2D of chidamide was 30 mg twice a week. Twenty-nine patients were enrolled in phase 2. In the intention-to-treat population (n = 37), overall response rate was 59.5% with a complete remission rate of 48.6%. The median DOR, progression-free survival (PFS), and overall survival (OS) were 25.3, 23.2, and 32.9 months, respectively. The most common grade 3 or higher treatment-emergent adverse events (AEs) were neutropenia (28.9%) and thrombocytopenia (10.5%), immune-related AEs were reported in 18 (47.3%) patients. Exploratory biomarker assessment suggested that a combination of dynamic plasma ctDNA and EBV-DNA played a vital prognostic role. STAT3 mutation shows an unfavorable prognosis. Although outcome of anticipate ORR was not achieved, sintilimab plus chidamide was shown to have a manageable safety profile and yielded encouraging CR rate and DOR in RR-ENKTL for the first time. It is a promising therapeutic option for this population.

Abemaciclib-induced epithelial-mesenchymal transition mediated by cyclin-dependent kinase 4/6 independent of cell cycle arrest pathway.

Abemaciclib (ABM), a cyclin-dependent kinase 4/6 inhibitor, shows pharmacological effects in cell cycle arrest. Epithelial-mesenchymal transition is an important cellular event associated with pathophysiological states such as organ fibrosis and cancer progression. In the present study, we evaluated the contribution of factors associated with cell cycle arrest to ABM-induced epithelial-mesenchymal transition. Treatment with 0.6 µM ABM induced both cell cycle arrest and epithelial-mesenchymal transition-related phenotypic changes. Interestingly, the knockdown of cyclin-dependent kinase 4/6, pharmacological targets of ABM or cyclin D1, which forms complexes with cyclin-dependent kinase 4/6, resulted in cell cycle arrest at the G1-phase and induction of epithelial-mesenchymal transition, indicating that downregulation of cyclin-dependent kinase 4/6-cyclin D1 complexes would mimic ABM. In contrast, knockdown of the Rb protein, which is phosphorylated by cyclin-dependent kinase 4/6, had no effect on the expression level of α-smooth muscle actin, an epithelial-mesenchymal transition marker. Furthermore, ABM-induced epithelial-mesenchymal transition was not affected by Rb knockdown, suggesting that Rb is not involved in the transition process. Our study is the first to suggest that cyclin-dependent kinase 4/6-cyclin D1 complexes, as pharmacological targets of ABM, may contribute to ABM-induced epithelial-mesenchymal transition, followed by clinical disorders such as organ fibrosis and cancer progression. This study suggests that blocking epithelial-mesenchymal transition might be a promising way to prevent negative side effects caused by a medication (ABM) without affecting its ability to treat the disease.

Microglial repopulation restricts ocular inflammation and choroidal neovascularization in mice.

Introduction: Age-related macular degeneration (AMD) is a prevalent, chronic and progressive retinal degenerative disease characterized by an inflammatory response mediated by activated microglia accumulating in the retina. In this study, we demonstrate the therapeutically effects and the underlying mechanisms of microglial repopulation in the laser-induced choroidal neovascularization (CNV) model of exudative AMD. Methods: The CSF1R inhibitor PLX3397 was used to establish a treatment paradigm for microglial repopulation in the retina. Neovascular leakage and neovascular area were examined by fundus fluorescein angiography (FFA) and immunostaining of whole-mount RPE-choroid-sclera complexes in CNV mice receiving PLX3397. Altered cellular senescence was measured by beta-galactosidase (SA-ß-gal) activity and p16INK4a expression. The effect and mechanisms of repopulated microglia on leukocyte infiltration and the inflammatory response in CNV lesions were analyzed. Results: We showed that ten days of the CSF1R inhibitor PLX3397 treatment followed by 11 days of drug withdrawal was sufficient to stimulate rapid repopulation of the retina with new microglia. Microglial repopulation attenuated pathological choroid neovascularization and dampened cellular senescence in CNV lesions. Repopulating microglia exhibited lower levels of activation markers, enhanced phagocytic function and produced fewer cytokines involved in the immune response, thereby ameliorating leukocyte infiltration and attenuating the inflammatory response in CNV lesions. Discussion: The microglial repopulation described herein are therefore a promising strategy for restricting inflammation and choroidal neovascularization, which are important players in the pathophysiology of AMD.

Selective but not pan-CDK inhibition abrogates 5-FU-driven tissue factor upregulation in colon cancer.

Thromboembolic events are complications in cancer patients and hypercoagulability has been linked to the tissue factor (TF) pathway, making this an attractive target. Here, we investigated the effects of chemotherapeutics and CDK inhibitors (CDKI) abemaciclib/palbociclib (CDK4/6), THZ-1 (CDK7/12/13), and dinaciclib (CDK1/2/5/9) alone and in combination regimens on TF abundance and coagulation. The human colorectal cancer (CRC) cell line HROC173 was treated with 5-FU or gemcitabine to stimulate TF expression. TF+ cells were sorted, recultured, and re-analyzed. The effect of treatment alone or in combination was assessed by functional assays. Low-dose chemotherapy induced a hypercoagulable state and significantly upregulated TF, even after reculture without treatment. Cells exhibited characteristics of epithelial-mesenchymal transition, including high expression of vimentin and mucin. Dinaciclib and THZ-1 also upregulated TF, while abemaciclib and palbociclib downregulated it. Similar results were observed in coagulation assays. The same anticoagulant activity of abemaciclib was seen after incubation with peripheral immune cells from healthy donors and CRC patients. Abemaciclib reversed 5-FU-induced TF upregulation and prolonged clotting times in second-line treatment. Effects were independent of cytotoxicity, senescence, and p27kip1 induction. TF-antibody blocking experiments confirmed the importance of TF in plasma coagulation, with Factor XII playing a minor role. Short-term abemaciclib counteracts 5-FU-induced hypercoagulation and eventually even prevents thromboembolic events.

A high dose KRP203 induces cytoplasmic vacuoles associated with altered phosphoinositide segregation and endosome expansion.

In animal cells, vacuoles are absent, but can be induced by diseases and drugs. While phosphoinositides are critical for membrane trafficking, their role in the formation of these vacuoles remains unclear. The immunosuppressive KRP203/Mocravimod, which antagonizes sphingosine-1-phosphate receptors, has been identified as having novel multimodal activity against phosphoinositide kinases. However, the impact of this novel KRP203 activity is unknown. Here, we show that KRP203 disrupts the spatial organization of phosphoinositides and induces extensive vacuolization in tumor cells and immortalized fibroblasts. The KRP203-induced vacuoles are primarily from endosomes, and augmented by inhibition of PIKFYVE and VPS34. Conversely, overexpression of PTEN decreased KRP203-induced vacuole formation. Furthermore, V-ATPase inhibition completely blunted KRP203-induced vacuolization, pointing to a critical requirement of the endosomal maturation process. Importantly, nearly a half of KRP203-induced vacuoles are significantly decorated with PI4P, a phosphoinositide typically enriched at the plasma membrane and Golgi. These results suggest a model that noncanonical spatial reorganization of phosphoinositides by KRP203 alters the endosomal maturation process, leading to vacuolization. Taken together, this study reveals a previously unrecognized bioactivity of KRP203 as a vacuole-inducing agent and its unique mechanism of phosphoinositide modulation, providing a new insight of phosphoinositide regulation into vacuolization-associated diseases and their molecular pathologies.