Furthermore, we provide evidence that the loss of a copy of chromosome 15 is responsible for reduced TSP-1 expression and thereby this aberration contributes to tumour vascularisation (i.e. the angiogenic switch) required for malignant growth.
Together, these data indicate that a disruption of the balance between VEGF and TSP-1 expression leads to a UVB-induced angiogenic switch, facilitating the infiltration of elastase-producing leucocytes and cutaneous photodamage.
The inverse association we found between TSP I and basic FGF suggests a different role of TSP I and TSP II in the angiogenic "switch," supporting the hypothesis that especially TSP I may have a significant function in tumor angiogenesis.