PROX1 and cancer: As VEGF-C is known to regulate lymphangiogenesis in various types of cancer cells [38, 39], we therefore screened gene expression profiling records from the GEO database for several lymphangiogenic genes, including vascular endothelial growth factor-C (VEGF-C), VEGF-B, ephrin type-B receptor-3 (EPHB3), angiomotin-like protein-2 (AMOTL2), angiomotin (AMOT) and prospero homeobox-1 (PROX1) (Figure 2A).