Fitm1, also known as fat storage-inducing transmembrane protein 1, is a transmembrane endoplasmic/sarcoplasmic reticulum protein involved in lipid droplet formation [3,4,5]. It belongs to a family of proteins that play important roles in lipid metabolism. Lipid droplets are dynamic organelles whose formation and growth are regulated processes, and Fitm1 is one of the proteins that may serve as a potential therapeutic target for diseases related to abnormal lipid metabolism, such as non-alcoholic fatty liver disease (NAFLD) [3].

In non-viral hepatocellular carcinoma (HCC), Fitm1 was identified as a novel tumor suppressor gene. Through a series of analyses including PCA, Uni-variate, Multi-variate, and LASSO cox regression, a FITM1-methylation-based signature was built and validated, which can predict the prognosis of non-viral HCC patients [1]. In pancreatic cancer, Fitm1 was among the down-regulated genes in cancer tissues compared to normal pancreatic tissues. Bioinformatics analysis showed that its down-regulation was significantly associated with the overall survival of pancreatic cancer patients [2]. In mice, neither constitutive Fitm1 (-/-) aged nor heart failure model mice showed significant differences in heart size or function, indicating a minor role of Fitm1 in heart-related chronic heart failure compared to Fitm2 [4].

In conclusion, Fitm1 is mainly involved in lipid droplet formation and lipid metabolism. Its role as a tumor suppressor in non-viral HCC and its association with the prognosis of pancreatic cancer patients, as well as its minor impact on heart function in mice, have been revealed through various research models. These findings contribute to understanding the biological functions of Fitm1 in different disease conditions and may provide new perspectives for disease treatment and prognosis prediction.