[Role of long non-coding ribonucleic acid in gastrointestinal cancer]

The long noncoding RNA LUCAT1 promotes tumorigenesis by controlling ubiquitination and stability of DNA methyltransferase 1 in esophageal squamous cell carcinoma

Available targeted therapies for esophageal squamous cell carcinoma (ESCC) are limited; thus, further genetic and epigenetic studies are needed. Recently, many long noncoding RNAs (lncRNAs) have been reported to be involved in various cancers. Here, we investigated whether the lncRNA LUCAT1 was related to the carcinogenesis of ESCC based on previous studies in lung cancer. LUCAT1 was significantly upregulated in ESCC cell lines and cancer tissue compared with normal cells and adjacent normal tissues. LUCAT1 knockdown reduced cell proliferation, induced apoptosis, and upregulated tumor-suppressor genes by reducing DNA methylation in KYSE-30 cells. Moreover, LUCAT1 siRNA reduced DNA methyltransferase 1 (DNMT1) protein levels without affecting transcription. Patients with high LUCAT1 expression had significantly lower survival rates than patients with low LUCAT1 expression. Our results thus suggest that LUCAT1 regulates the stability of DNMT1 and inhibits the expression of tumor suppressors through DNA methylation, leading to the formation and metastasis of ESCC. We identified LUCAT1 as a potential target for drug development and as a biomarker for ESCC.

The role of lncRNAs in hepatocellular carcinoma: opportunities as novel targets for pharmacological intervention

Long non-coding RNA (lncRNA) is commonly defined as an RNA with a length of greater than 200 nucleotides, frequently up to 100 kb. Numerous studies have shown that dysregulation of lncRNAs may directly relate to a number of human diseases, particularly in oncology where lncRNAs appear to play an important role. LncRNAs may also play a potentially novel and critical role in the development and progression of hepatocellular carcinoma (HCC). This article discusses lncRNAs as a new possibility for diagnostic and therapeutic approaches for HCC. The authors introduce the relationship between some lncRNAs and HCC, including carcinogenesis, development, metastasis and prognosis. In addition, the authors suggest that the discovery of lncRNAs may encourage the discovery and development of new therapeutic modalities for HCC and that their regulation may be a promising potential treatment for HCC. Clinical studies are required to determine the therapeutic effect of regulating lncRNA in humans with HCC.