Slc12a7, a member of the solute carrier family 12, encodes a potassium-chloride cotransporter (KCC4) [4]. It is involved in cellular volume regulation and may participate in various biological processes related to ion homeostasis [3,4,5].

In adrenocortical carcinoma (ACC), amplification and overexpression of Slc12a7 are frequently observed. Enforced Slc12a7 overexpression in SW-13 cells (with negligible endogenous expression) promoted motility and invasive characteristics, increased cellular attachment and detachment turnover, potentially through increased filopodia formation and/or Ezrin interaction. Conversely, RNAi-mediated gene silencing of Slc12a7 in NCI-H295R cells (with robust endogenous expression) stymied cell attachment strength, migration, and invasion capacity. Transcription factor expression analysis indicated that multiple signaling pathways, such as osmotic stress, bone morphogenetic protein, and Hippo signaling pathways, may be affected by Slc12a7 overexpression [1]. Also, in ACC, IGF1 overexpression (caused in part by gene amplifications) is correlated with Slc12a7 overexpression in non-functional, early-stage tumors, suggesting a potential IGF1-Slc12a7-targeted therapeutic opportunity [2].

In conclusion, Slc12a7 plays a significant role in regulating cellular behaviors like motility, invasion, and adhesion, especially in adrenocortical carcinoma. The findings from in vitro studies on ACC cell lines enhance our understanding of the gene's function in cancer-related biological processes, potentially providing insights for targeted cancer therapies.