Lenvatinib Targets PDGFR-β Pericytes and Inhibits Synergy with Thyroid Carcinoma Cells: Novel Translational Insights

Context: Pericyte populations abundantly express tyrosine kinases (eg, platelet-derived growth factor receptor-β [PDGFR-β]) and impact therapeutic response. Lenvatinib is a clinically available tyrosine kinase inhibitor that also targets PDGFR-β. Duration of therapeutic response was shorter in patients with greater disease burden and metastasis. Patients may develop drug resistance and tumor progression. Objectives: Develop a gene signature of pericyte abundance to assess with tumor aggressiveness and determine both the response of thyroid-derived pericytes to lenvatinib and their synergies with thyroid carcinoma-derived cells. Design: Using a new gene signature, we estimated the relative abundance of pericytes in papillary thyroid carcinoma (PTC) and normal thyroid (NT) TCGA samples. We also cocultured CD90+;PAX8- thyroid-derived pericytes and BRAFWT/V600E-PTC-derived cells to determine effects of coculture on paracrine communications and lenvatinib response. Results: Pericyte abundance is significantly higher in BRAFV600E-PTC with hTERT mutations and copy number alterations compared with NT or BRAFWT-PTC samples, even when data are corrected for clinical-pathologic confounders. We have identified upregulated pathways important for tumor survival, immunomodulation, RNA transcription, cell-cycle regulation, and cholesterol metabolism. Pericyte growth is significantly increased by platelet-derived growth factor-BB, which activates phospho(p)-PDGFR-β, pERK1/2, and pAKT. Lenvatinib strongly inhibits pericyte viability by down-regulating MAPK, pAKT, and p-p70S6-kinase downstream PDGFR-β. Critically, lenvatinib significantly induces higher BRAFWT/V600E-PTC cell death when cocultured with pericytes, as a result of pericyte targeting via PDGFR-β. Conclusions: This is the first thyroid-specific model of lenvatinib therapeutic efficacy against pericyte viability, which disadvantages BRAFWT/V600E-PTC growth. Assessing pericyte abundance in patients with PTC could be essential to selection rationales for appropriate targeted therapy with lenvatinib

Lysosome-associated membrane protein-2 deficiency increases the risk of reactive oxygen species-induced ferroptosis in retinal pigment epithelial cells

Lysosome-associated membrane protein-2 (LAMP2), is a highly glycosylated lysosomal membrane protein involved in chaperone mediated autophagy. Mutations of LAMP2 cause the classic triad of myopathy, cardiomyopathy and encephalopathy of Danon disease (DD). Additionally, retinopathy has also been observed in young DD patients, leading to vision loss. Emerging evidence show LAMP2-deficiency to be involved in oxidative stress (ROS) but the mechanism remains obscure. In the present study, we found that tert-butyl hydroperoxide or antimycin A induced more cell death in LAMP2 knockdown (LAMP2-KD) than in control ARPE-19 cells. Mechanistically, LAMP2-KD reduced the concentration of cytosolic cysteine, resulting in low glutathione (GSH), inferior antioxidant capability and mitochondrial lipid peroxidation. ROS induced RPE cell death through ferroptosis. Inhibition of glutathione peroxidase 4 (GPx4) increased lethality in LAMP2-KD cells compared to controls. Cysteine and glutamine supplementation restored GSH and prevented ROS-induced cell death of LAMP2-KD RPE cells

Changes in the Burden of Comorbidities in Patients with COPD and Asthma-COPD Overlap According to the GOLD 2017 Recommendations

PURPOSE: Comorbidities associated with chronic obstructive pulmonary disease (COPD) affect quality of life and increase mortality. Asthma-COPD overlap (ACO) may express a different profile of comorbidities compared to COPD alone. It is unclear how recent changes in GOLD recommendations affect the profile of comorbidities in COPD and ACO. METHODS: Eight hundred and thirty-four patients with COPD were recruited from 67 Hungarian secondary care outpatient clinics, 469 of them had ACO. Comorbidities were defined by respiratory specialists based on medical history, patient report, and medications. COPD grades were defined according to the old 2016 and the new 2017 GOLD document. Comorbidities were compared along COPD ABCD groups determined by the old and new GOLD. RESULTS: 66 and 72% of the COPD patients in groups C and D (GOLD 2016) were recategorized to groups A and B (GOLD 2017), respectively. There was no difference in the prevalence of disorders along the 2016 GOLD categories except for osteoporosis in ACO (p = 0.01). When the patients were categorized according to the 2017 GOLD criteria, the prevalence of osteoporosis (p = 0.01) was different among the four groups in all COPD patients. Subgroup analysis of non-ACO COPD patients revealed inter-group differences for cardiac arrhythmia (p < 0.01). No alteration was seen in the prevalence of coronary artery disease, hypertension, diabetes, or the total number of comorbidities. CONCLUSION: A significant number of patients are recategorized according to the GOLD 2017 criteria. This change only marginally affects the profile of comorbidities; still this needs to be considered when assessing the patients in daily practice