ABSTRACT
Circular RNAs (circRNAs) are a novel type of endogenous RNAs featuring stable structure and high tissue-specific expression. Recently, accumulating evidence has revealed that aberrant circRNAs expression plays important roles in carcinogenesis and tumor progression. However, the expression pattern and biological function of circRNAs in non small cell lung cancer (NSCLC) remain largely unknown. Therefore, the purpose of this study was to clarify the possible role of one of typical circRNAs, circRNA_100876 in NSCLC and to define its prognostic value in NSCLC. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expression of circRNA_100876 in tumor tissues and their adjacent nontumorous tissues in 101 patients with NSCLC. We found that the expression level of circRNA_100876 was significantly elevated in NSCLC tissues when compared with their adjacent nontumorous tissues (P=0.000). Moreover, there was a close correlation between the circRNA_100876 up-regulation expression and lymph node metastasis (P=0.001) and tumor staging (P=0.001) in NSCLC. In addition, Kaplan-Meier survival analysis demonstrated that the overall survival time of NSCLC patients with high circRNA_100876 expression was significantly shorter than those patients with low circRNA_100876 expression (P=0.000). In conclusion, our findings indicate that circRNA_100876 is closely related to the carcinogenesis of NSCLC and it might be served as a potential prognostic biomarker and therapeutic target for NSCLC.
Subject(s)
Biomarkers, Tumor/genetics , Carcinoma, Non-Small-Cell Lung/diagnosis , Lung Neoplasms/diagnosis , RNA/genetics , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/pathology , Female , Gene Expression Regulation, Neoplastic , Humans , Kaplan-Meier Estimate , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Lymphatic Metastasis , Male , Middle Aged , Neoplasm Staging , Prognosis , RNA, Circular , Up-RegulationABSTRACT
Expression of lymphoid enhancer factor 1 (LEF1) is frequently altered in different human cancers. This study aimed to assess LEF1 expression in colon cancer tissues and to explore changed phenotypes, gene expressions, and the possible mechanism after knocked down LEF1 expression in colon cancer cell lines. A total of 106 colon cancer and matched paratumorous normal tissues were used to assess LEF1 expression using immunohistochemistry and qRT-PCR. LEF1 lentivirus was used to knockdown LEF1 expression for the assessment of cell viability, cell cycle distribution, apoptosis, and gene expressions. The nude mouse xenograft assay was performed to detect the effects of LEF1 knockdown in vivo. The data showed that the levels of LEF1 mRNA and protein were significantly increased in human colon cancer tissues compared to the matched paratumorous normal tissues and were associated with infiltration depth, lymph node and distant metastases, advanced TNM (tumor-node-metastasis) stages, and shorter overall survival. Furthermore, LEF1 knockdown reduced tumor cell viability, invasion capacity, MMP2 and MMP-9 expression, but induced apoptosis. Nude mouse xenograft assay showed that LEF1 knockdown suppressed tumor formation and growth in vivo. In addition, the expression of Notch pathway-related proteins RBP-jκ and Hes1 was reduced in LEF1 knockdown cells. Taken together, LEF1 protein was overexpressed in colon cancer tissues and knockdown of LEF1 expression inhibited colon cancer growth in vitro and in vivo. These data suggest that targeting of LEF1 expression should be further evaluated for colon cancer prevention and therapy.
