Moreover, in breast cancer cells, it was found that the expression level of SLC1A5 was regulated by the protooncogene HPIP, and in response to chronic glucose stress, HPIP was deregulated by ubiquitination of E3 ubiquitin ligase RNF2, which affected the glutamine metabolism level of breast cancer cells [108]. Here, MUL1 is linked to breast carcinoma.