Lsm8, a member of the SM-like (LSM) gene family encoding RNA-binding proteins, is crucial for multiple biological processes. It is part of the nuclear LSm2-8 complex which acts as a chaperone for U6 spliceosomal RNA and is involved in mRNA regulation, potentially through influencing mRNA stability [3,4]. Lsm8 is also implicated in pathways related to cell division and RNA splicing [2].

Depletion of nuclear LSm8 in cell-based studies increased the number of cytoplasmic processing bodies (P-bodies), while its overexpression led to P-body loss. Lsm8 knockdown caused relocalization of LSm4 and LSm6 proteins to the cytoplasm and was proposed to control nuclear accumulation of all LSm2-7 proteins. This redistribution might create new binding sites for other P-body components and nucleate new structures [1]. In Hepatitis B virus (HBV) replication models, siRNA-mediated knockdown of LSm8 reduced viral RNA levels, suggesting a role in HBV biosynthesis [4]. In mantle cell lymphoma, LSM8 was overexpressed in the LSM.index-high group, which was associated with poor survival outcomes, and elevated LSM gene expression was linked to increased cell division and RNA splicing pathway activity [2]. In gastric cancer, a higher level of Lsm8 was associated with 5-fluorouracil chemoresistance [5].

In conclusion, Lsm8 is essential for mRNA regulation, P-body formation, and has implications in viral replication and cancer progression. Studies using loss-of-function approaches in cell models and patient samples have revealed its role in these biological processes and disease conditions, highlighting its potential as a therapeutic target in diseases like mantle cell lymphoma and gastric cancer.