Vascular endothelial growth factor (VEGF) signaling is a critical regulator of vasculogenesis, angiogenesis, and lymphangiogenesis, processes that are vital for the development of vascular and lymphatic systems, tissue repair, and the maintenance of homeostasis. VEGF ligands and their receptors orchestrate endothelial cell proliferation, migration, and survival, playing a pivotal role in dynamic vascular remodeling. Dysregulated VEGF signaling drives diverse pathological conditions, including tumor angiogenesis, cardiovascular diseases, and ocular disorders. Excessive VEGF activity promotes tumor growth, invasion, and metastasis, while insufficient signaling contributes to impaired wound healing and ischemic diseases. VEGF-targeted therapies, such as monoclonal antibodies and tyrosine kinase inhibitors, have revolutionized the treatment of diseases involving pathological angiogenesis, offering significant clinical benefits in oncology and ophthalmology. These therapies inhibit angiogenesis and slow disease progression, but they often face challenges such as therapeutic resistance, suboptimal efficacy, and adverse effects. To further explore these issues, this review provides a comprehensive overview of VEGF ligands and receptors, elucidating their molecular mechanisms and regulatory networks. It evaluates the latest progress in VEGF-targeted therapies and examines strategies to address current challenges, such as resistance mechanisms. Moreover, the discussion includes emerging therapeutic strategies such as innovative drug delivery systems and combination therapies, highlighting the continuous efforts to improve the effectiveness and safety of VEGF-targeted treatments. This review highlights the translational potential of recent discoveries in VEGF biology for improving patient outcomes.

Vascular pericytes, an important cellular component in the tumor microenvironment, are often associated with tumor vasculatures, and their functions in cancer invasion and metastasis are poorly understood. Here we show that PDGF-BB induces pericyte–fibroblast transition (PFT), which significantly contributes to tumor invasion and metastasis. Gain- and loss-of-function experiments demonstrate that PDGF-BB-PDGFRβ signaling promotes PFT both in vitro and in in vivo tumors. Genome-wide expression analysis indicates that PDGF-BB–activated pericytes acquire mesenchymal progenitor features. Pharmacological inhibition and genetic deletion of PDGFRβ ablate the PDGF-BB–induced PFT. Genetic tracing of pericytes with two independent mouse strains, TN-AP-CreERT2:R26R-tdTomato and NG2-CreERT2:R26R-tdTomato, shows that PFT cells gain stromal fibroblast and myofibroblast markers in tumors. Importantly, coimplantation of PFT cells with less-invasive tumor cells in mice markedly promotes tumor dissemination and invasion, leading to an increased number of circulating tumor cells and metastasis. Our findings reveal a mechanism of vascular pericytes in PDGF-BB–promoted cancer invasion and metastasis by inducing PFT, and thus targeting PFT may offer a new treatment option of cancer metastasis. Significance We show that vascular pericytes significantly contribute to cancer invasion and metastasis by the mechanism of the pericyte–fibroblast transition (PFT). This study proposes this concept and indicates the vascular pericyte’s role. Vascular pericytes were considered to remodel tumor vessels toward a mature phenotype. However, once dissociated from tumor vessels their functions within the tumor tissue are not known. In the present study, we show that pericytes, once detached from tumor microvasculatures, underwent differentiation to become stromal fibroblasts, which are known to contribute to tumor invasion and metastasis. Our results show that vascular pericytes are the important source of stromal fibroblasts and targeting PFT may offer a new treatment option in cancer metastasis.

Metastasis is the leading cause of cancer-associated mortality and the underlying mechanisms of cancer metastasis remain elusive. Both blood and lymphatic vasculatures are essential structures for mediating distal metastasis. The vasculature plays multiple functions, including accelerating tumor growth, sustaining the tumor microenvironment, supplying growth and invasive signals, promoting metastasis, and causing cancer-associated systemic disease. VEGF is one of the key angiogenic factors in tumors and participates in the initial stage of tumor development, progression and metastasis. Consequently, VEGF and its receptor-mediated signaling pathways have become one of the most important therapeutic targets for treating various cancers. Today, anti-VEGF-based antiangiogenic drugs (AADs) are widely used in the clinic for treating different types of cancer in human patients. Despite nearly 20-year clinical experience with AADs, the impact of these drugs on cancer metastasis and systemic disease remains largely unknown. In this review article, we focus our discussion on tumor VEGF in cancer metastasis and systemic disease and mechanisms underlying AADs in clinical benefits.

Glucose uptake is essential for cancer glycolysis and is involved in non-shivering thermogenesis of adipose tissues^1–6. Most cancers use glycolysis to harness energy for their infinite growth, invasion and metastasis^2,7,8. Activation of thermogenic metabolism in brown adipose tissue (BAT) by cold and drugs instigates blood glucose uptake in adipocytes^4,5,9. However, the functional effects of the global metabolic changes associated with BAT activation on tumour growth are unclear. Here we show that exposure of tumour-bearing mice to cold conditions markedly inhibits the growth of various types of solid tumours, including clinically untreatable cancers such as pancreatic cancers. Mechanistically, cold-induced BAT activation substantially decreases blood glucose and impedes the glycolysis-based metabolism in cancer cells. The removal of BAT and feeding on a high-glucose diet under cold exposure restore tumour growth, and genetic deletion of Ucp1—the key mediator for BAT-thermogenesis—ablates the cold-triggered anticancer effect. In a pilot human study, mild cold exposure activates a substantial amount of BAT in both healthy humans and a patient with cancer with mitigated glucose uptake in the tumour tissue. These findings provide a previously undescribed concept and paradigm for cancer therapy that uses a simple and effective approach. We anticipate that cold exposure and activation of BAT through any other approach, such as drugs and devices either alone or in combination with other anticancer therapeutics, will provide a general approach for the effective treatment of various cancers.

Objective Pancreatic ductal adenocarcinoma (PDAC) is the most lethal malignancy and lacks effective treatment. We aimed to understand molecular mechanisms of the intertwined interactions between tumour stromal components in metastasis and to provide a new paradigm for PDAC therapy. Design Two unselected cohorts of 154 and 20 patients with PDAC were subjected to correlation between interleukin (IL)-33 and CXCL3 levels and survivals. Unbiased expression profiling, and genetic and pharmacological gain-of-function and loss-of-function approaches were employed to identify molecular signalling in tumour-associated macrophages (TAMs) and myofibroblastic cancer-associated fibroblasts (myoCAFs). The role of the IL-33–ST2–CXCL3–CXCR2 axis in PDAC metastasis was evaluated in three clinically relevant mouse PDAC models. Results IL-33 was specifically elevated in human PDACs and positively correlated with tumour inflammation in human patients with PDAC. CXCL3 was highly upregulated in IL-33-stimulated macrophages that were the primary source of CXCL3. CXCL3 was correlated with poor survival in human patients with PDAC. Mechanistically, activation of the IL-33–ST2–MYC pathway attributed to high CXCL3 production. The highest level of CXCL3 was found in PDAC relative to other cancer types and its receptor CXCR2 was almost exclusively expressed in CAFs. Activation of CXCR2 by CXCL3 induced a CAF-to-myoCAF transition and α-smooth muscle actin (α-SMA) was uniquely upregulated by the CXCL3–CXCR2 signalling. Type III collagen was identified as the CXCL3–CXCR2-targeted adhesive molecule responsible for myoCAF-driven PDAC metastasis. Conclusions Our work provides novel mechanistic insights into understanding PDAC metastasis by the TAM-CAF interaction and targeting each of these signalling components would provide an attractive and new paradigm for treating pancreatic cancer.