The lack of effect of carnosine on SLC15A4 mRNA abundance was unexpected, since small interfering RNA (SiRNA)-mediated knockdown of both receptors (SLC15A3 and SLC15A4) was found to significantly reduce carnosine transport in human glioblastoma cells (Oppermann et al. 2019). The gene discussed is SLC15A4; the disease is glioblastoma.