Downregulated expression of exosomal long non-coding RNA UCA1 in plasma of patients with non-small cell lung cance

Long non-coding RNAs (lncRNAs), mainly found in the nucleus of cells, are involved in different gene expression and regulation processes. Growing evidence has shown that abnormalities in the expression levels of lncRNAs play an important role in tumour metastasis, invasion, and proliferation, especially in non-small cell lung cancer (NSCLC). LncRNAs were also found to be upregulated or downregulated in exosomes secreted by cancer cells, thus they have the potential to be used as a non-invasive cancer biomarker. In this study, the expression of exosomal lncRNA UCA1 was determined on 29 plasma samples of patients with NSCLC and 29 controls who did not have NSCLC or related lung diseases by quantitative PCR using SYBR Green. Then, statistical analyses were used to evaluate the association between the expression of lncRNA UCA1 and some pathological features of NSCLC. The results showed that lncRNA UCA1 was downregulated in the exosomes of NSCLC patients compared with the control group (p=0.050), especially in the early stage (stage I + II). However, there was no association between the expression of lncRNA UCA1 and some pathological features of NSCLC, such as age, sex, smoking, alcohol consumption, tumour size, disease stage, lymph nodes, or tumour metastasis. This study provided the initial data on the expression of exosomal lncRNA UCA1 in the plasma of Vietnamese patients with NSCLC and further studies on the larger samples are needed to be continued.