NOTE

🌱 created from: clinical_immuno-oncology

development_and_structure_of_the_lymphoid_system

• Lymphatic System:

  • A complex, blind-ended vascular network distinct from the blood circulatory system.
  • It plays essential roles in:
    • Tissue fluid homeostasis
    • Nutrient uptake
    • Immune function regulation

• Lymphatic Vessels & Endothelial Cells:

  • Lymphatic vessels exhibit unique features aiding in:
    • Uptake of substances
    • Transport back to the blood circulation
  • Lymphatic endothelial cells are specialized and their:
    • Specification and differentiation are controlled by molecular programs.
    • Heterogeneity and plasticity lead to the creation of tissue- and organ-specific vascular beds.

• Lymph Nodes:

  • Lymph nodes are complex structures containing unique layers of endothelial cells.
  • Function as key immune surveillance centers.
  • Schematic of structure and LEC heterogeneity of lymph node.

• Lymphatics in Cancer:

  • Present in the tumor microenvironment, actively involved in tumor metastasis.
  • Tumor-associated lymphatic vessels have distinct molecular profiles compared to normal lymphatics.
  • Crosstalk between tumors and lymphatic vessels significantly contributes to:
    • Cancer progression
    • Metastasis

• Key Growth Factors:

  • VEGFC and VEGFD are major growth factors that attract VEGFR3-expressing lymphatic endothelial cells, accelerating tumor lymphangiogenesis.

• Current Knowledge Gaps:

  • Most research is limited to specific cancer types such as:
    • Melanoma
    • Breast cancer
    • Glioblastomas
  • More exploration is needed across other cancer types.