ALG9-IT1: ALG9-IT1 is a long non-coding RNA (lncRNA) that has been found to be significantly downregulated in liver tissues from patients with non-alcoholic fatty liver disease (NAFLD) compared to control samples [PMC9260751]. The expression levels of two other lncRNAs, LINC00240 and RBMS3-AS3, were found to be significantly upregulated in the liver tissues of NAFLD patients [PMC9260751]. The expression levels of LINC00240 and ALG9-IT1 were consistent with the results of bioinformatics analysis, while RBMS3-AS3 showed an opposite trend [PMC9260751]. These lncRNAs, including ALG9-IT1, may play a role in attenuating liver fibrosis in NAFLD by influencing the extracellular matrix through a competing endogenous RNA (ceRNA) network [PMC9260751]. In addition to NAFLD, ALG9-IT1 has also been found to be strongly correlated with the progression of esophageal carcinoma [PMC8486540]. Furthermore, ALG9-IT1 is expressed specifically in T-helper cell subtypes ThP, Th0, Th1 and Th2, while another lncRNA called CTD-2113 L7.1 is expressed in all T cells investigated [PMC4240855]. In conclusion, ALG9-IT1 is a downregulated lncRNA that may have functional roles in NAFLD and esophageal carcinoma. Its expression pattern suggests its involvement in liver fibrosis attenuation through the ceRNA network. Furthermore, its specific expression pattern in T-helper cell subtypes indicates its potential role in immune regulation. These findings highlight the potential importance of ALG9-IT1 as a biomarker or therapeutic target for various diseases.