👤 John F Keaney

Cancer is among the leading causes of death in the USA and worldwide. Solid tumors require the formation of new blood vessels (angiogenesis) for their growth. The endothelium plays a crucial role in angiogenesis and tumor progression. Hypoxic stress generated by tumors can activate stress kinases such as mixed lineage kinases (MLKs). Publicly available datasets on lung adenocarcinoma, along with our experimental findings, indicate that MLK2 and MLK3 are expressed in human lung tumors. In this study, using three distinct mouse models of tumor development, we demonstrated that MLK2 (MAP3K10) and MLK3 (MAP3K11) are essential for tumor growth and angiogenesis. Furthermore, MLK2 and MLK3 are highly expressed in the endothelium and are necessary for endothelial proliferation, migration, and angiogenesis. In the endothelium, MLKs regulate the expression of angiogenic growth factors and metalloproteinases, including Pgf, Vegfa, Angptl4, Adam8, and Mmp9. Additionally, the MLK family of kinases acts through the long noncoding RNA (lncRNA) H19 to control the expression of these pro-angiogenic factors in the endothelium. Collectively, these findings suggest that the MLK-H19 axis coordinates endothelial function, angiogenesis, and tumor growth. Show less

Vps34 PI3K is thought to be the main producer of phosphatidylinositol-3-monophosphate, a lipid that controls intracellular vesicular trafficking. The organismal impact of systemic inhibition of Vps34 kinase activity is not completely understood. Here we show that heterozygous Vps34 kinase-dead mice are healthy and display a robustly enhanced insulin sensitivity and glucose tolerance, phenotypes mimicked by a selective Vps34 inhibitor in wild-type mice. The underlying mechanism of insulin sensitization is multifactorial and not through the canonical insulin/Akt pathway. Vps34 inhibition alters cellular energy metabolism, activating the AMPK pathway in liver and muscle. In liver, Vps34 inactivation mildly dampens autophagy, limiting substrate availability for mitochondrial respiration and reducing gluconeogenesis. In muscle, Vps34 inactivation triggers a metabolic switch from oxidative phosphorylation towards glycolysis and enhanced glucose uptake. Our study identifies Vps34 as a new drug target for insulin resistance in Type-2 diabetes, in which the unmet therapeutic need remains substantial. Show less

C-reactive protein (CRP) is a heritable marker of chronic inflammation that is strongly associated with cardiovascular disease. We sought to identify genetic variants that are associated with CRP levels. We performed a genome-wide association analysis of CRP in 66 185 participants from 15 population-based studies. We sought replication for the genome-wide significant and suggestive loci in a replication panel comprising 16 540 individuals from 10 independent studies. We found 18 genome-wide significant loci, and we provided evidence of replication for 8 of them. Our results confirm 7 previously known loci and introduce 11 novel loci that are implicated in pathways related to the metabolic syndrome (APOC1, HNF1A, LEPR, GCKR, HNF4A, and PTPN2) or the immune system (CRP, IL6R, NLRP3, IL1F10, and IRF1) or that reside in regions previously not known to play a role in chronic inflammation (PPP1R3B, SALL1, PABPC4, ASCL1, RORA, and BCL7B). We found a significant interaction of body mass index with LEPR (P<2.9×10(-6)). A weighted genetic risk score that was developed to summarize the effect of risk alleles was strongly associated with CRP levels and explained ≈5% of the trait variance; however, there was no evidence for these genetic variants explaining the association of CRP with coronary heart disease. We identified 18 loci that were associated with CRP levels. Our study highlights immune response and metabolic regulatory pathways involved in the regulation of chronic inflammation. Show less