👤 L Frati

Low-density lipoprotein cholesterol (LDL-C) has traditionally been the primary biomarker used to assess cardiovascular risk. However, a substantial proportion of cardiovascular events occur in individuals with LDL-C levels within the normal range, highlighting the need for additional risk markers. Lipoprotein(a) [Lp(a)] has emerged as an independent and genetically determined cardiovascular risk factor that is not adequately captured by conventional lipid profiling. Elevated Lp(a) levels are associated with an increased risk of atherosclerotic cardiovascular disease, including coronary artery disease, ischemic stroke, and calcific aortic valve stenosis, and appear to be particularly relevant in the context of premature cardiovascular events. The pathogenicity of Lp(a) is driven by distinct mechanisms that extend beyond cholesterol transport. These include pro-atherogenic, pro-inflammatory, and pro-thrombotic effects mediated largely by oxidized phospholipids carried by the particle and by the structural properties of apolipoprotein(a), which interfere with fibrinolysis. Despite its strong and stable genetic determination, Lp(a) remains underrecognized and inconsistently measured in clinical practice, partly due to historical limitations in assay standardization and reporting. This minireview summarizes current knowledge on the pathophysiological mechanisms underlying elevated Lp(a), discusses its clinical implications for cardiovascular risk assessment, and highlights the importance of standardized Lp(a) measurement in routine practice, particularly in light of emerging Lp(a)-targeted therapies. Show less

Dual-specificity phosphatase 6 (DUSP6, mitogen-activated protein kinase (MAPK) phosphatase 3 or PYST1) dephosphorylates phosphotyrosine and phosphothreonine residues on extracellular signal-regulated kinase (ERK1/2; MAPK1/2) to inactivate the ERK1/2 kinase. DUSP6 is a critical regulator of the ERK signaling cascade and has been implicated as a tumor suppressor. We report here experimental evidences that DUSP6 is transcriptionally upregulated in primary and long-term cultures of human glioblastoma, as assayed by northern hybridization and real-time quantitative PCR, producing constitutive high level of protein expression. Functional assays were performed with adenovirus-mediated expression of DUSP6 in glioblastoma cultures. Protein overexpression inhibits growth by inducing G1-phase delay and increased mitogenic/anchorage dependence and clonogenic potential in vitro. Changes in cell morphology were associated with an increased tumor growth in vivo. Chemoresistance is a major cause of treatment failure and poor outcome in human glioblastomas. Importantly, DUSP6 overexpression increased resistance to cisplatin-mediated cell death in vitro and in vivo. Antisense-mediated depletion of DUSP6 acted in lowering the threshold to anticancer DNA-damaging drugs. We conclude that upregulation of DUSP6 exerts a tumor-promoting role in human glioblastomas exacerbating the malignant phenotype. Show less