CD44 and breast cancer: Consistent with this view, in a recent work, it was reported that several genes encoding for enzymes responsible for nucleotide de novo synthesis, namely Prps2, Ppat, Pfas Gmps, and Gart, were up-regulated in 4TO7Lung cells, murine breast cancer cells with higher lung metastatic behavior, and were positively correlated to cancer metastasis, cell stemness (i.e., CD44 and CD24 positive cells) and worse survival [30].