- Intratumoral Gene expression and germline polymorphism of genes involved in the vascular endothelial growth factor (VEGF) and VEGF independent pathways (VEGF, vascular endothelial growth factor receptor 1 [VEGFR1], VEGFR2, interleukin-8 [IL8], chemokine (C-X-C motif) receptor 2 [CXCR2], intercellular adhesion molecule [ICAM], VEGFR1 and VEGFR2, neuropilin 1 or 2 [NRP1,2], cluster of differentiation [CD] 44, aldehyde dehydrogenase [ALDH], leucine-rich repeats and immunoglobulin-like [LRIG].