Septin6 is a member of the septin family of GTP-binding proteins. Septins are involved in cytoskeleton and membrane organization, cell division, and host-pathogen interactions [4]. Septin6, in particular, has been shown to regulate protein sorting during multivesicular body (MVB) biogenesis by binding to F-actin and interacting with AP-3 and ESCRT-I complexes [4]. It may also play roles in cell growth and casein synthesis in dairy cow mammary epithelial cells via the mTORC1 pathway [2].

Rearrangements involving Septin6 have been implicated in leukemia. For example, the fusion of MLL (now known as KMT2A) and Septin6 has been observed in acute monocytic leukemia and acute myeloid leukemia. In these cases, the MLL/Septin6 rearrangements were often cryptic or complex, and the 5'-MLL/Septin6-3' transcript was located on the derivative X chromosome [1,3,5,6]. A case of AML-M4-infant with KMT2A::Septin6 fusion and DIS3 variant was reported, suggesting that this co-existence might contribute to disease progression [3].

In conclusion, Septin6 has important functions in cellular processes such as MVB biogenesis and cell growth regulation. Its involvement in leukemia through gene fusions with MLL (KMT2A) highlights its significance in understanding the pathogenesis of certain hematological malignancies. The study of Septin6 in these contexts provides insights into disease mechanisms and potential therapeutic targets. [1,2,3,4,5,6]