ATP8B1 and colorectal carcinoma: However, in another study, ATP8B1 was suggested as a tumor suppressor for CRC since the forced reduction in ATP8B1 expression either by CRISPR/Cas9 or shRNA was associated with increased growth and proliferation of the CRC cell line HT29, while an overexpression of ATP8B1 resulted in reduced growth and proliferation of the SW480 CRC cell line [47].