Sez6l2, or Seizure Related 6 Homolog Like 2, is a protein-coding gene. It has implications in neuronal and motor function development, and is a type 1 transmembrane protein highly expressed in the hippocampus and cerebellar cortex [1,7].

In oncology, Sez6l2 has been studied in multiple cancers. In breast cancer, knockdown of Sez6l2 suppressed cell proliferation, induced cell cycle arrest at G1 phase, and repressed migration and invasion, while overexpression had the opposite effects. It was also found that upstream transcription factor 1 (USF1) positively regulated its transcription [2].

In colorectal cancer, knockdown of Sez6l2 inhibited cell growth and colony formation, impaired growth by inducing caspase-dependent apoptosis mediated by mitochondria-related proteins, and was inversely correlated with cytochrome C expression in malignant tissues. High Sez6l2 expression was associated with poor prognosis [3].

In thyroid carcinoma, increased expression of Sez6l2 was correlated with a dismal prognosis and was an independent risk factor for progression-free interval [4].

In cholangiocarcinoma, overexpression of Sez6l2 predicted poor prognosis, and it was related to promoting angiogenesis through growth factors and the P38-MAPK pathway [6].

In colon cancer, SEZ6L2 overexpression was a potential biomarker, promoted cell viability, and was associated with declining survival rates, while bexarotene treatment downregulated its expression and reduced cell viability [8].

In neurology, anti-Sez6l2 antibodies have been associated with paraneoplastic cerebellar syndrome and cerebellar ataxia, and intense sequential immunotherapy may improve the condition of some patients with Sez6l2 antibody-associated cerebellar ataxia [1,5].

In conclusion, Sez6l2 is crucial for neuronal and motor function development. In cancer, its overexpression often serves as a negative prognostic marker and is involved in promoting tumor growth, metastasis, and angiogenesis across various cancer types. In neurology, Sez6l2-associated autoimmunity can lead to cerebellar syndromes. Understanding Sez6l2 through in vivo and functional studies provides insights into disease mechanisms and potential therapeutic targets.