A subpopulation of cells marked by CD13 expression, high asymmetric cell division, slow proliferation rates compared with CD133-negative tumor cells, is less sensitive to the anti-proliferative effects of Vemurafenib, and accumulates with treatment, suggesting a role for these cells in tumor escape from BRAF V600E inhibition and recurrence (69). The gene discussed is ANPEP; the disease is neoplasm.