LncRNA ES3 Is Upregulated in High-Grade CRC and Its Expression Is Elevated Along with Increasing Tumor Size

Cancer Stem Cell (CSC) is known as a minor percentage of tumor cells inside various malignancies with shared common features with embryonic stem cells such as self-renewal capability and pluripotency. It is believed that not only stemness transcription factors but also pluripotent lncRNAs regulate various aspects of CSCs. It was demonstrated that the embryonic lncRNAs regulate the main features of these cells through interacting with ESC-associated transcription factors. LncRNA ES3 is a pluripotent lncRNA that was demonstrated to sustain the stemness status of human embryonic stem cells. However, there is little evidence for its contributory role in tumorigenesis. Therefore, in the present study, the possible expression of ES3 transcript in collected Colorectal Cancer (CRC) tissues and their non-tumor marginal samples were explored by employing the RT-qPCR strategy. Then, we accomplished a survival analysis of ES3 based on the TCGA database. Inconsistent with metadata, our results revealed that the ES3 expression markedly increased in CRC tissues rather than non-tumor marginal specimens. Furthermore, we detected that the ES3 expression meaningfully increased in high-grade and high-stage CRC tissues compared to low-grade and low-stage ones, respectively. Moreover, ES3 was significantly upregulated in tumor tissues along with increasing tumor size of CRC samples. Our findings, for the first time, demonstrated that lncRNA ES3 is expressed in CRC and its expression may contribute to the tumorigenesis process and progression of CRC. Hence, lncRNA ES3 can be regarded as a new cancer biomarker with possible utility in the diagnosis, prognosis, and therapy of colorectal cancer.