MicroRNAs (miRNAs) have been shown to be dysregulated in virus-related cancers; however,miRNA regulation of virus-related cancer development and progression remains poorly understood.Here,we report that miR-148a is repressed by hepatitis B virus (HBV) X protein (HBx) to promote cancer growth and metastasis in a mouse model of hepatocellular carcinoma (HCC).Hematopoietic pre-B cell leukemia transcription factor-interacting protein (HPIP) is an important regulator of cancer cell growth.We used miRNA target prediction programs to identify miR-148a as a regulator of HPIP.Expression of miR-148a in hepatoma cells reduced HPIP expression,leading to repression of AKT and ERK and subsequent inhibition of mTOR through the AKT/ERK/FOXO4/ATF5 pathway.