Epidemiological trends of neuroendocrine tumours over three decades in Queensland, Australia.

INTRODUCTION: While neuroendocrine tumours (NETs) account for only a small proportion of cancer diagnoses, incidence has been rising over time. We examined incidence, mortality and survival over three decades in a large population-based registry study. METHODS: This retrospective study included all cases (n = 4580) of NETs diagnosed from 1986 to 2015 in Queensland, Australia. We examined directly age-standardised incidence and mortality rates. The impact on overall survival according to demographic factors and primary site was modelled using multivariable Cox proportional hazards regression (HR). Cause-specific and relative survival were estimated using the Kaplan-Meier survival function. RESULTS: Annual incidence increased from 2.0 in 1986 to 6.3 per 100,000 in 2015, while mortality remained stable. The most common primary site was appendix followed by lung, small intestine and rectum. Rectal, stomach, appendiceal and pancreatic NETs had the greatest rate increase, while lung NETs decreased over the same period. Five-year cause-specific survival improved from 69.4% during 1986-1995 to 92.6% from 2006 to 2015. Survival was highest for appendiceal and rectal NETs and lowest for pancreas and unknown primary sites. The risk of dying within five years of diagnosis was about 40% higher for males (HR = 1.41, 95%CI 1.20-1.65) and significantly higher for patients aged over 40 years compared to younger patients (p < 0.001). CONCLUSION: This study, including 30 years of data, found significantly increasing rates of NETs and confirms results from elsewhere. Increasing survival over time in this study, likely reflects increased awareness, improvements in diagnostic imaging, greater use of endoscopy and colonoscopy, and the development of new therapies.

Diabetic Vascular Calcification Mediated by the Collagen Receptor Discoidin Domain Receptor 1 via the Phosphoinositide 3-Kinase/Akt/Runt-Related Transcription Factor 2 Signaling Axis.

Objective- Vascular calcification is a common and severe complication in patients with atherosclerosis which is exacerbated by type 2 diabetes mellitus. Our laboratory recently reported that the collagen receptor discoidin domain receptor 1 (DDR1) mediates vascular calcification in atherosclerosis; however, the underlying mechanisms are unknown. During calcification, vascular smooth muscle cells transdifferentiate into osteoblast-like cells, in a process driven by the transcription factor RUNX2 (runt-related transcription factor 2). DDR1 signals via the phosphoinositide 3-kinase/Akt pathway, which is also central to insulin signaling, and upstream of RUNX2, and this led us to investigate whether DDR1 promotes vascular calcification in diabetes mellitus via this pathway. Approach and Results- Ddr1+/+ ; Ldlr-/- (single knock-out) and Ddr1-/- ; Ldlr-/- (double knock-out) mice were placed on high-fat diet for 12 weeks to induce atherosclerosis and type 2 diabetes mellitus. Von Kossa staining revealed reduced vascular calcification in the aortic arch of double knock-out compared with single knock-out mice. Immunofluorescent staining for RUNX2 was present in calcified plaques of single knock-out but not double knock-out mice. Primary vascular smooth muscle cells obtained from Ddr1+/+ and Ddr1-/- mice were cultured in calcifying media. DDR1 deletion resulted in reduced calcification, a 74% reduction in p-Akt levels, and an 88% reduction in RUNX2 activity. Subcellular fractionation revealed a 77% reduction in nuclear RUNX2 levels in Ddr1-/- vascular smooth muscle cells. DDR1 associated with phosphoinositide 3-kinase, and treatment with the inhibitor wortmannin attenuated calcification. Finally, we show that DDR1 is important to maintain the microtubule cytoskeleton which is required for the nuclear localization of RUNX2. Conclusions- These novel findings demonstrate that DDR1 promotes RUNX2 activity and atherosclerotic vascular calcification in diabetes mellitus via phosphoinositide 3-kinase/Akt signaling.

Oxidized Low-Density Lipoprotein Loading of Macrophages Downregulates TLR-Induced Proinflammatory Responses in a Gene-Specific and Temporal Manner through Transcriptional Control.

Hypercholesterolemia is a key risk factor for atherosclerosis and leads to the uptake of native and oxidized low-density lipoprotein (oxLDL) by macrophages (Mϕs) and foam cell formation. Inflammatory processes accompany Mϕ foam cell formation in the artery wall, yet the relationship between Mϕ lipid loading and their response to inflammatory stimuli remains elusive. We investigated proinflammatory gene expression in thioglycollate-elicited peritoneal Mϕs, bone marrow-derived Mϕs and dendritic cells, and RAW264.7 cells. Loading with oxLDL did not induce peritoneal Mϕ apoptosis or modulate basal-level expression of proinflammatory genes. Upon stimulation of TLR4, the rapid induction of IFN-ß was inhibited in cells loaded with oxLDL, whereas the induction of other proinflammatory genes by TLR4 (LPS), TLR3 (polyriboinosinic-polyribocytidylic acid), TLR2 (Pam3CSK4), and TLR9 (CpG) remained comparable within the first 2 h. Subsequently, the expression of a subset of proinflammatory genes (e.g., IL-1ß, IL-6, CCL5) was reduced in oxLDL-loaded cells at the level of transcription. This phenomenon was partially dependent on NF erythroid 2-related factor 2 (NRF2) but not on nuclear liver X receptors α and ß (LXRα,ß), peroxisome proliferator-activated receptor-γ (PPARγ), and activating transcription factor 3 (ATF3). LPS-induced NF-κB reporter activity and intracellular signaling by NF-κB and MAPK pathways were comparable in oxLDL-loaded Mϕs, yet the binding of p65/RelA (the prototypic NF-κB family member) was reduced at IL-6 and CCL5 promoters. This study revealed that oxLDL loading of Mϕs negatively regulates transcription at late stages of TLR-induced proinflammatory gene expression and implicates epigenetic mechanisms such as histone deacetylase activity.