The extrahepatic expression of NTCP was corroborated by the non-negligible levels of the full-length NTCP transcript in 5 liver and 15 non-liver cells (Figure 1B), indicating that the high levels of HBV production in non-liver cells, such as MCF-7, also occur through NTCP-mediated infection. The gene discussed is SLC10A1; the disease is infection.