RASA1 and neoplasm: Similarly, Sun et al. found that downregulation of miR-31 significantly decreased cell proliferation in vitro and showed a significant decrease in tumor size in vivo with Caco-2 and HT-29 human colorectal adenocarcinoma cells by directly targeting RAS p21 GTPase activating protein 1 (RASA1), a regulator of the RAS-MAPK pathway [36].