SLCO4A1 and colorectal carcinoma: Interestingly, although we also observed a positive correlation between SLCO4A1-AS1 expression and SLCO4A1 mRNA levels in CRC tissues, force expression or knockdown of SLCO4A1-AS1 in CRC cells exhibited weak or no significant effect on the expression of SLCO4A1 (Additional file 9: Fig. S3a, b).