Angiogenesis最新文献

Hereditary Hemorrhagic Telangiectasia (HHT) is a rare autosomal dominant vascular disorder characterized by mucocutaneous telangiectasias and visceral arteriovenous malformations (AVMs), which arise due to direct connections between arteries and veins. These vascular lesions are prone to bleeding and vascular shunts, leading to recurrent epistaxis and GI bleeding, among other systemic complications. HHT is caused by heterozygous loss-of-function mutations in genes involved in the BMP9/BMP10 signaling pathway—primarily ENG, ACVRL1 (also known as ALK1), and SMAD4—which define the major HHT subtypes (HHT1, HHT2, and HHT-JP). HHT has a global prevalence of 1 in 5000 individuals, affecting approximately 1.6 million worldwide. The 15th International HHT Scientific Conference was held in Mandelieu-la-Napoule, France, bringing together over 376 attendees from around the world, including 77 trainees, to share the latest advances in HHT research and clinical care. The conference received 225 abstract submissions, of which 49 were selected for oral presentations and 176 for poster sessions. This gathering marked a significant milestone in the field, not only for its scale but also for the depth and breadth of the scientific discussions. Key highlights included new insights into AVM biology, disease mechanisms, genetic underpinnings, and emerging therapeutic strategies. In addition to oral and poster sessions, two focused workshops provided in-depth discussion on pulmonary arterial hypertension (PAH) and HHT, a rare occurrence of two disease states where treatment for one often worsens the other, and a discussion on the evolving definition of HHT and whether it should be revised in light of recent advances in research, genetic testing, and clinical evidence beyond the Curacao criteria, which were established 25 years ago. This executive summary aims to recapitulate the key scientific and clinical findings presented at the conference and to spotlight areas of continued debate and unmet need. We hope this summary will serve as a resource for experts working in the field and as an invitation for new investigators and clinicians to engage in collaborative efforts to advance the understanding and treatment of HHT.

Angiogenesis, the formation of new blood vessels from existing ones, is essential for physiological and pathological processes such as wound healing, organ development, and tumor growth. It is a tightly regulated process influenced by both intrinsic and extrinsic factors. Emerging evidence shows a connection between biological clocks that regulate physiological rhythms and angiogenesis through the modulation of angiogenic factors like vascular growth factor (Vegfa). Thus, the clock system can directly modulate the timing and efficiency of angiogenic processes. This study aimed to investigate the role of key circadian clock genes, Bmal1 and Per2, in retinal angiogenesis. Endothelial cell-specific deletion of these genes significantly impairs vessel growth, although distinct phenotypic differences emerge between the two knockout models as angiogenesis progresses. RNA-sequencing (RNA-seq) analysis of retinal endothelial cells reveals that circadian clocks predominantly influence the expression of genes involved in cell proliferation. Notably, vascular endothelial cell (VEC) proliferation is diurnally regulated and is disrupted in Bmal1 knockout animals, leading to an increase in the number of Brn3a-positive retinal ganglion cells (RGCs). These alterations are further associated with compromised retinal circuitry and function. Thus, this study uncovers critical roles for Bmal1 and Per2 in regulating retinal angiogenesis, emphasizing the importance of circadian control of cell proliferation in vascular development and retinal function.

Deleterious mutations in the GDF2 gene, encoding BMP9, are causative of pulmonary arterial hypertension and hereditary haemorrhagic telangiectasia. Paradoxically, BMP9 germ-line knockout (Gdf2^−/−; Bmp9 KO) and double Bmp9 KO/conditional Bmp10 cKO (dKO) mice exhibit an attenuated response to PAH-inducing stimuli. We asked whether this contradiction is due to the pathological, physiological, or genetic consequences of BMP9 knockout. In Bmp9 KO mice we observed reduced pulmonary vascular smooth muscle cell (SMC) coverage and using RNA-seq analysis of Bmp9 KO mouse lungs identified two novel genes, COLQ and ITGA6, which were differentially regulated in a human PAH RNA-seq dataset. In order to study BMP10 loss, postnatal tamoxifen treatment was required to induce Bmp10 cKO. As previously reported, in dKO mice we observed cardiomegaly and splenomegaly, as well as hyperplasia and hemosiderosis in the pulmonary vasculature. Surprisingly, tamoxifen treated Bmp9 KO control mice phenocopied these pathological changes in dKO mice and downregulated SMC marker gene transcription. Loss of BMP10 is not critical for severe tissue remodelling in the lung, heart, and spleen, rather Bmp9 KO mice appear sensitive to tamoxifen and BMP9 loss is the primary cause of mild vessel remodelling due to a basal reduction of smooth muscle cell coverage. This study suggests that interaction of the BMP pathway with tamoxifen needs to be carefully considered when studying Bmp9 KO mice and urges caution in the context of tamoxifen use when studying cardiovascular and pulmonary disease models.

Quaking (QKI), a member of the signal transduction and activators of RNA (STAR) family of RNA-binding proteins, affects a wide range of functions, including alternative splicing, mRNA precursor processing, mRNA transport and localization, mRNA stabilization, and translation. Recently, QKI has been found to have critical roles in vasculogenesis and angiogenesis due to its effects on alternate splicing and other post-transcriptional modifications involving small RNAs in the endothelial cells (ECs). Aberrant expression or mutation of QKI in ECs can result in pro- or anti-angiogenic effects under different physiological and pathological conditions, including tumor angiogenesis. However, the regulatory roles of QKI in EC biology remain poorly described. This review summarizes our current understanding of the QKI isoforms and their functions in ECs, as well as the potential utility of QKI as an emerging translational target for angiogenic-based therapies.

Microvascular network formation is governed by a variety of factors, with interstitial flow (IF) playing a pivotal role. However, the impact of multidirectional IF (MDIF) on microvascular network development remains insufficiently explored. In this study, we developed a platform consisting of a Square chip capable of generating MDIF and a deep learning-based Vasculature-on-a-Chip Analysis Tool (VoCAT) for high-efficient analysis of vascular morphology on the chip. Using this platform, we demonstrated that microvascular networks formed on the Square chip exhibited intricate structural features with enhanced functionality. We also demonstrated its utility in modeling a tumor microenvironment with complex microvascular networks and observed enhanced tumor cell migration. This study provides the first evidence that MDIF promotes microvascular network formation, offering new perspectives for advanced in vitro vascular and disease research.

Diabetic retinopathy (DR) is characterized by chronic retinal inflammation and vascular remodeling that can threaten vision. Most current treatments are administered intravitreally and target vascular endothelial growth factor A (VEGF) but are often ineffective. Nevertheless, few alternative treatments, and no oral DR therapies, exist. Although IL-1β, TNFα, and IL-8 are upregulated along with VEGF within eyes with DR, they are not therapeutically targeted. IL-8 levels correlate with DR progression and resistance to anti-VEGF therapy, suggesting VEGF-independent contributions of IL-8-receptor signaling to DR. IL-1β and TNFα, in turn, enhance expression of pro-angiogenic CXCR2 ligands (e.g. IL-8, CXCL1) in human Müller cells (hMC). Despite investigation of CXCR2 roles in several angiogenic and fibrotic diseases, CXCR2 inhibitors have not been explored in DR models. In this study, we show protein upregulation of IL-8 and CXCL1, but no detectable VEGF in conditioned media (CM) from IL-1β and TNFα-stimulated hMC. Stimulation of human retinal microvascular endothelial cells (hRMEC) with this human Müller cell-conditioned media (hMC-CM), as well as directly with IL-8, upregulated hRMEC proliferation and migration. CXCR2 inhibition reduced pro-angiogenic hRMEC responses to hMC-CM and IL-8. Likewise, in vivo, in the oxygen-induced retinopathy (OIR) model, either genetic (Cxcr2^-/-) or pharmacologic (SB225002) CXCR2 inhibition reduced pre-retinal neovascularization without altering avascularity or VEGF expression. These findings suggest that: (a) Müller cells may link inflammatory and angiogenic responses in the retina, (b) CXCR2 activation may contribute to DR, and (c) CXCR2 inhibitors may be repurposed to reduce pre-retinal neovascularization, a key feature of proliferative DR.

This letter aims to provide a forward-looking analysis of the recent preclinical study by Ou et al. (Angiogenesis, 2025) on the efficacy of the multi-kinase inhibitor KC1036 in Ewing sarcoma (ES).We conducted a critical appraisal of the reported data, focusing on the dual anti-angiogenic and direct anti-tumor mechanisms of KC1036. The analysis is contextualized within the current understanding of ES pathogenesis and treatment resistance.The original study compellingly demonstrates that KC1036, by concurrently inhibiting VEGFR and FGFR signaling, effectively suppresses ES growth. While these findings are promising, they raise pivotal questions for future investigation. Key considerations include the precise mechanistic interplay between KC1036 and the EWSR1-FLI1 oncogenic driver, the potential evolution of resistance despite multi-targeted inhibition, and the critical assessment of the agent’s therapeutic index.KC1036 represents a rational and potent therapeutic candidate for ES. The primary challenges ahead lie in delineating its molecular mechanisms of action beyond angiogenesis, prospectively defining resistance pathways to guide combination therapies, and rigorously evaluating its safety profile to ensure successful clinical translation. This letter outlines these priorities to stimulate further research.