Identification of lncRNA, miRNA and mRNA expression profiles and ceRNA Networks in small cell lung cancer

Abstract

Background Small cell lung cancer (SCLC) is a highly lethal malignant tumor. It accounts for approximately 15% of newly diagnosed lung cancers. Long non-coding RNAs (lncRNAs) can regulate gene expression and contribute to tumorigenesis through interactions with microRNAs (miRNAs). However, there are only a few studies reporting the expression profiles of lncRNAs, miRNAs, and mRNAs in SCLC. Also, the role of differentially expressed lncRNAs, miRNAs, and mRNAs in relation to competitive endogenous RNAs (ceRNA) network in SCLC remain unclear. Results In the present study, we first performed next generation sequencing (NGS) with six pairs of SCLC tumors and adjacent non-cancerous tissues obtained from SCLC patients. Overall, 29 lncRNAs, 48 miRNAs, and 510 mRNAs were found to be differentially expressed in SCLC samples (|log2[fold change] | > 1; P < 0.05). Bioinformatics analysis was performed to predict and construct a lncRNA-miRNA-mRNA ceRNA network, which included 9 lncRNAs, 11 miRNAs, and 392 mRNAs. Four up-regulated lncRNAs and related mRNAs in the ceRNA regulatory pathways were selected and validated by quantitative PCR. In addition, we examined the role of the most upregulated lncRNA, TCONS_00020615, in SCLC cells. We found that TCONS_00020615 may regulate SCLC tumorigenesis through the TCONS_00020615–hsa-miR-26b-5p–TPD52 pathway. Conclusions Taken together, our findings may help identify some potential biomarkers and therapy targets for SCLC. Also, our study may provide new evidence for the underlying regulatory mechanism in SCLC.

Decoding long non‑coding RNAs: Friends and foes in cancer development (Review)

“…Irregular levels of lncRNA expression can play a pivotal role in the development of various types of cancer, serving as a significant regulatory factor in their onset with a predictive potential (8). lncRNAs can perform diverse biological functions in different types of cancers, such as regulating gene expression, metabolism, immunity, influencing cell proliferation, controlling apoptosis and affecting tumor metastasis (13)(14)(15)(16). These versatile molecules can act as oncogenes, promoting cancer growth, or tumor suppressors, inhibiting tumor progression, or both depending on the specific context and type of cancer.…”