TRPV1 and neoplasm: The absence of mitosis in the surviving MCF7GFP-TRPV1 cells subsequently did not allow for the establishment of stable MCF7GFP-TRPV1 clones, although we had been successful in establishing cell clones permanently expressing ectopic TRPV1 proteins using non-tumor-derived cell lines such as HaCaT, a spontaneously immortalized keratinocyte cell line from adult human skin (Pecze et al., 2008), or NIH-3T3 cells, a spontaneously immortalized mouse embryo fibroblast cell line (Olah et al., 2007).