Screening And Identification Of ESR1 As A Target Of Icaritin In Hepatocellular Carcinoma Evidence From Bibliometrics And Bioinformatic Analysis

ObjectiveThere are significant sex differences in the incidence and mortality of hepatocellular carcinoma(HCC).Compared with men,the incidence and mortality of HCC in women are relatively low.The estrogen signaling pathway,which includes estrogen and estrogen receptors,has been postulated to have a protective effect on the occurrence and development of HCC.In 2022,icaritin,a traditional Chinese medicine with estrogen-like activities,was recommended by the CSCO guidelines as a systematic treatment for patients with advanced HCC due to its clinical safety and efficacy.However,the mechanism and targets of icaritin are unclear.In this study,we aimed to analyze the potential targets of icaritin in the treatment of HCC through bibliometrics and bioinformatics methods,understand its mechanism of action,and lay a theoretical foundation for the treatment of HCC with icaritin.MethodsFirst,literature related to icaritin was downloaded from the Web of Science.The software programs "Rstudio”,“VOSviewer” and “Mendeley Desktop”were used to analyze the distribution of icaritin publications and research hotspots.Meanwhile,icaritin-related genes were obtained by combining them with the Pub Chem database.Second,transcriptome data of HCC patients were obtained from the TCGA database.The protein-protein interaction(PPI)analysis of icaritin-related gene was performed using the STRING data platform,the visualization and network topology analysis were performed using Cytoscape.Univariate and multivariate COX regression analyses were combined to screen the hub targets that could independently affect the prognosis of patients with HCC,and the results were verified by the HCC transcriptome data in the ICGC database.The docking activity of the target gene with icaritin was analyzed by molecular docking.Finally,HCC cell lines with target gene overexpression and interference were constructed,and the effect of this gene on the icaritin sensitivity of HCC cells was verified by cell proliferation experiments.ResultsA total of 239 icaritin-related articles were obtained,and 292 icaritin-related genes were obtained by combining them with the Pub Chem database,among which 100 genes were differentially expressed in cancer tissues and adjacent tissues of HCC patients.The protein interactions between 100 genes were analyzed,a core module containing 34 genes was obtained by module division,of which CASP3,ESR1 and CDKN2 A were the top three core genes.Univariate and multivariate COX regression analyses showed that ESR1 was an independent prognostic factor.Molecular docking results showed that ESR1 and icaritin had a high affinity.Functional studies revealed that ESR1 inhibits HCC cell malignant proliferation and improves the sensitivity of HCC cells to icaritin.ConclusionWe used bibliometrics for the first time to analyze icaritin publications.Bioinformatics was combined to screen the potential target of icaritin in HCC and verified in vitro.We propose that ESR1,as a target of icaritin,may be conducive to improving icaritin therapy sensitivity in HCC.