UHRF1, an epigenetic regulator present in proliferating cancer cells, interacts with AMPK, inhibiting its activity in both normal and stress conditions. As a nuclear protein, UHRF1 promotes the retention of AMPK in the nucleus and significantly reduces its activity against substrates such as H2B and EZH2. Additionally, UHRF1 effectively decreases AMPK activity in the cytoplasm, likely as a result of the nucleocytoplasmic shuttling of AMPK (22). Previous studies revealed possible effects of UHRF1 protein in the different cancer types. For example, Q et al. in 2019 revealed that UHRF1 knockdown drastically reduced aerobic glycolysis in pancreatic cancer cells. Furthermore, they found that UHRF1 knockdown also reduced hypoxia-inducible factor (HIF)1 levels and HIF1 targeting glycolytic genes (23). Based on the study of Yin et al. in 2018, UHRF1/BRCA1 complex is one of the main targets of poly ADP ribose polymerase (PARP) inhibitor and histone deacetylase (HDAC) inhibitor (24).
Previous studies also mentioned the possible roles of UHRF1 in the regulation of BC, GC, and CRC. In mammalian cells, UHRF1 aids in the creation and maintenance of DNA methylation patterns. The establishment domains, including E3 ligase activity, are well described, whereas the maintenance domains are less understood. In human CRC cells, UHRF1's ability to bind histone- and hemimethylated DNA, but not its E3 ligase activity, maintains cancer-specific DNA methylation patterns. Disruption of these chromatin reader activities leads to the restoration of DNA hypermethylation, reactivation of epigenetically silenced tumor suppressor genes (TSGs), and a reduction in the oncogenic properties of CRC (25). Y et al. 2012 reported that UHRF1 has a significant role in the cellular proliferation biological process and might affect CRC risk through this pathway (26). Based on the study of Y et al. in 2019, miR-506 could have a significant regulatory effect on the KISS1/PI3K/NF-kB signaling pathway through silencing UHRF1 in CRC patients (27). The report of J et al. in 2021 revealed the possible effect of UHRF1 silencing on the STAT1 and DNMT1 regulation and inhibition of CRC growth (28). Our results are consistent with the mentioned previous studies. Based on our results, up-regulation of UHRF1 has a significant correlation with the higher risk of CRC.
Based on the study of Luo G. et al. in 2022, UHRF1 regulates the estrogen signaling pathway and could regulate cell growth in BC patients (29). UHRF1 could enhance BC development through KLF17 suppression. This suppression happens using promoter hypermethylation (30). In GC patients, miR-146a/b could regulate GC invasion and metastasis by targeting UHRF1 (31).
No prior research has explored the potential roles of ZNF213-AS1 in the development of breast cancer, gastric cancer, and colorectal cancer. Based on our study, EMX2OS and ZNF213-AS1 are the two potential regulatory diagnostic biomarkers of BC, GC, and CRC. The mentioned lncRNAs might affect the DNA methylation and gene expression signaling pathways through the regulation of UHRF1 expression level. Furthermore, we found that miR-4479 could modulate DNA methylation and gene expression signaling pathways via negative regulation of UHRF1. No previous research has investigated the potential role of miR-4479 in BC, CRC, and GC. However, previous studies revealed the potential roles of this microRNA in ovarian cancer and lung cancer. Based on the study of Wang et al. in 2022, miR-4479 has a significantly low expression in epithelial ovarian cancer (EOC) patients. Furthermore, miR-4479 could be considered as a potential diagnostic biomarker of EOC (32). According to the 2022 study by Chakraborty et al., miR-4479 targets genes that are up-regulated and overexpressed in lung cancer (33). Our previous studies also revealed potential coding and non-coding biomarkers of BC (34–37) and GC (38).
Based on previous studies, lncRNA EMX2OS regulates the invasion and regulation of ovarian cancer cells through the regulation of PD-L1/AKT3/miR-654-3p (39). In The GC samples, EMX2OS could be an enhancer RNA and regulate the prognosis of EMX2OS (40) In 2021, Molaei Ramshe et al. conducted a study on the expression level of EMX2OS in breast cancer patients and found no significant change in the expression levels of EMX2OS in breast cancer samples (41). However, more studies are needed for the validation of the obtained results in this experiment.