ARHGEF2 and cancer: GEF, guanine nucleotide exchange factor; CRC, colorectal cancer; βpix, βPak-interacting exchange factor; ALDH, aldehyde dehydrogenase; CAF, cancer-associated fibroblast; FOLFOX, folinic acid, fluorouracil, oxaliplatin; FOLFIRI, folinic acid, fluorouracil, irinotecan; EMT, epithelial-to-mesenchymal transition.