RESUMEN
INTRODUCTION: Cancer-derived circulating components are increasingly considered as candidate sources for non-invasive diagnostic biomarkers. This study aimed to investigate the expression of tumor-educated platelet (TEP) long non-coding RNAs (lncRNAs) in colorectal cancer (CRC) patients and determine whether it could be served as a potential tool for CRC diagnosis. MATERIALS AND METHODS: Relative quantitative real-time PCR (qRT-PCR) was used to detect the expression levels of three cancer-related platelet-derived lncRNAs CCAT1, HOTTIP, and XIST in 75 CRC patients and 42 healthy controls. Quantitative data were analyzed by SPSS (IBM Corp., Armonk, NY, USA) for comparison of cancer and non-cancer individuals. The receiver operating characteristic (ROC) curve analysis was further performed to assess the diagnostic values of lncRNAs within the CRC patients. RESULTS: The expression levels of lncRNAs colon cancer associated transcript 1 (CCAT1) (P = 0.006) and HOXA transcript at the distal tip (HOTTIP) (P = 0.049), but not X-inactive specific transcript (XIST) (P = 0.12), were significantly upregulated in CRC patients compared to healthy individuals. However, there were no significant correlations between platelet lncRNAs and clinicopathological characteristics, including sex, age, tumor location, differentiation, and size (all at P > 0.05). The area under the ROC curve (AUC) of the lncRNA CCAT1 was 0.61 (sensitivity, 71%; specificity, 50%). CONCLUSION: TEP lncRNA CCAT1 is detectable in the circulation of CRC patients and could be considered as a potential diagnostic biomarker.
RESUMEN
Long noncoding RNAs (lncRNAs) have been demonstrated to regulate a variety of cell processes and involve in the development and progression of colorectal cancer (CRC). Recently, the circulating lncRNAs have emerged as minimally invasive biomarkers for cancer diagnosis and prognosis. We aimed to examine the plasma expression level of long noncoding RNAs lnc-ATB, lnc-CCAT1, and lnc-OCC-1 in CRC patients and evaluate the clinical values. A total of 74 pretreatment CRC and 74 healthy blood biopsies were subjected to differentially evaluate the expression levels of three lncRNAs (OCC-1, CCAT1, and ATB). Briefly, after plasma separation and total RNA extraction, RNAs were reversely transcribed to complementary DNA followed by amplification using a quantitative real-time polymerase chain reaction technique for lncRNA expression analysis. The results showed that the expression levels of lnc-ATB (p < 0.001) and CCAT1 (p = 0.024), but not OCC-1 (p = 0.24), were significantly upregulated in the CRC compared with the healthy group. The calculated AUC of ROC was 0.78 (95% confidence interval [CI]: 0.811-0.94) for lnc-ATB and 0.64 (95% CI: 0.811-0.94) for CCAT1, which were indicative of a high discriminatory power (p < 0.001). The highest accuracy for lncRNA-ATB was obtained at a cutoff point of 2.5, which corresponded to sensitivity and specificity of 82% and 75%, respectively. Our results suggested a significant accuracy of lncRNA-ATB and lncRNA-CCAT1 in distinguishing CRC patients from healthy individuals.
