losartan-potassium and Small-Cell-Lung-Carcinoma

Darbepoetin alfa, an erythropoiesis-stimulating agent (ESA), is used in cancer patients as a supportive care for anemia. For small-cell lung cancer (SCLC), several studies have shown that the administration of ESAs does not affect survival but decreases the need for blood transfusions and improves the quality of life (QOL) of patients receiving chemotherapy. The present randomized phase II study assessed the feasibility, efficacy, and safety of the administration of darbepoetin alfa to patients with SCLC receiving dose-dense (every 2 weeks) standard chemotherapy consisting of carboplatin plus etoposide, pegfilgrastim prophylactically. Seventy-four chemotherapy-naive patients with limited or extensive SCLC received combination chemotherapy for 6 cycles, and half of the patients additionally received darbepoetin to achieve a target hemoglobin concentration of 12-13 g/dL. The primary study outcome, progression-free survival, showed no difference between the 2 arms of the study. Among the secondary endpoints, objective response was similar in the presence and absence of darbepoetin (best response rates = 75.0% vs. 77.8%). Likewise, 1-year survival rates were not different between the 2 treatment arms (40.1% vs. 45.9%). There were no significant differences in grade 3/4 toxicities. As expected, the need for blood transfusions differed significantly: 19.4% of patients in the darbepoetin arm received transfusions versus 38.9% in the control arm. Analysis of European Organization for Research and Treatment of Cancer quality of life questionnaire (EORTC QLQ-C30) scales at different time points showed that the darbepoetin group's QOL was significantly better for certain readouts and never significantly worse than that of the control group. Thus, the combination of darbepoetin alfa with dose-dense carboplatin plus etoposide was feasible and well tolerated. Addition of darbepoetin alfa to chemotherapy lowered the need for blood transfusions and did not affect measures of survival and objective response.

Topics: Adult; Aged; Aged, 80 and over; Anemia; Antineoplastic Combined Chemotherapy Protocols; Blood Transfusion; Carboplatin; Darbepoetin alfa; Disease-Free Survival; Erythropoietin; Etoposide; Female; Hematinics; Humans; Kaplan-Meier Estimate; Lung Neoplasms; Male; Middle Aged; Quality of Life; Small Cell Lung Carcinoma

Chemoresistance is the crux of clinical treatment failure of small-cell lung cancer (SCLC). Cancer stem cells play a critical role in therapeutic resistance of malignant tumors. Studies have shown that the role of erythropoietin-producing hepatocellular A2 (EphA2) in tumors is complex. This study aimed to test the hypothesis that ligand-independent activation of EphA2 modulates chemoresistance by enhancing stemness in SCLC. We verified that EphA2 was activated in chemoresistance sublines in a ligand-independent manner rather than a ligand-dependent manner. Ligand-independent EphA2 enhanced the expression of stemness-associated biomarkers (CD44, Myc, and SOX2), accelerated epithelial-mesenchymal transition (EMT) and reinforced self-renewal to drive the chemoresistance of SCLC, while the P817H mutant EphA2 neutralized intrinsic function. Co-immunoprecipitation (co-IP) and GST-pull down experiments were conducted to verify that EphA2 directly interacted with PRMT1. Moreover, EphA2 increased the expression and activity of PRMT1. Whereafter, PRMT1 interacted with and methylated SOX2 to induce stemness and chemoresistance in SCLC. Pharmacological inhibition of EphA2 showed a synergistic anti-tumor effect with chemotherapy in preclinical models, including patient-derived xenograft (PDX) models. These findings highlight, for the first time, that the EphA2/PRMT1/SOX2 pathway induces chemoresistance in SCLC by promoting stemness. EphA2 is a potential therapeutic target in SCLC treatment.

Topics: Cell Line, Tumor; Drug Resistance, Neoplasm; Erythropoietin; Humans; Ligands; Lung Neoplasms; Methylation; Protein-Arginine N-Methyltransferases; Repressor Proteins; Small Cell Lung Carcinoma; SOXB1 Transcription Factors