LncRNA-cCSC1 modulates cancer stem cell properties in colorectal cancer via activation of the Hedgehog signaling pathway.

Several long noncoding RNAs (lncRNAs) have been identified in various malignant tumors and determined to contribute to the process of tumorigenesis, including that of colorectal cancer (CRC). Cancer stem cells (CSCs) have been demonstrated to promote the expansion and maintain the invasion and metastasis of cancer cells, owing to their self-renewal capacity. However, the underlying modulation mechanism of CSC-associated lncRNAs in CRC remains largely unclear. Using integrated bioinformatic analysis, we identified a novel lncRNA (lncRNA-cCSC1) that is highly expressed in CRC and colorectal cancer stem cells (CRCSCs). The biological functions of lncRNA-cCSC1 were assessed in vitro and vivo through the silencing or upregulation of its expression. The depletion of lncRNA-cCSC1 markedly inhibited the self-renewal capacity of the CRCSCs and reduced their drug resistance to 5-fluorouracil. In contrast, lncRNA-cCSC1 overexpression increased the self-renewal effect. Furthermore, aberrant lncRNA-cCSC1 expression resulted in a concomitant alteration of smoothened (SMO) and GLI family zinc finger 1 (Gli1) expression in the Hedgehog (Hh) signaling pathway. Our study is the first to identify a novel lncRNA-cCSC1 in CRC and to indicate that it may regulate CSC-like properties via the Hh signaling pathway. Thus, lncRNA-cCSC1 could be a potential biomarker and promising therapeutic target for CRC.

Zhou H ，Xiong Y ，Peng L ，Wang R ，Zhang H ，Fu Z ... -  《-》

LncRNA-Hh Strengthen Cancer Stem Cells Generation in Twist-Positive Breast Cancer via Activation of Hedgehog Signaling Pathway.

Cancer stem cells (CSCs) are a subpopulation of neoplastic cells with self-renewal capacity and limitless proliferative potential as well as high invasion and migration capacity. These cells are commonly associated with epithelial-mesenchymal transition (EMT), which is also critical for tumor metastasis. Recent studies illustrate a direct link between EMT and stemness of cancer cells. Long non-coding RNAs (lncRNAs) have emerged as important new players in the regulation of multiple cellular processes in various diseases. To date, the role of lncRNAs in EMT-associated CSC stemness acquisition and maintenance remains unclear. In this study, we discovered that a set of lncRNAs were dysregulated in Twist-positive mammosphere cells using lncRNA microarray analysis. Multiple lncRNAs-associated canonical signaling pathways were identified via bioinformatics analysis. Especially, the Shh-GLI1 pathway associated lncRNA-Hh, transcriptionally regulated by Twist, directly targets GAS1 to stimulate the activation of hedgehog signaling (Hh). The activated Hh increases GLI1 expression, and enhances the expression of SOX2 and OCT4 to play a regulatory role in CSC maintenance. Thus, the mammosphere-formation efficiency (MFE) and the self-renewal capacity in vitro, and oncogenicity in vivo in Twist-positive breast cancer cells are elevated. lncRNA-Hh silence in Twist-positive breast cells attenuates the activated Shh-GLI1 signaling and decreases the CSC-associated SOX and OCT4 levels, thus reduces the MFE and tumorigenesis of transplanted tumor. Our results reveal that lncRNAs function as an important regulator endowing Twist-induced EMT cells to gain the CSC-like stemness properties.

Zhou M ，Hou Y ，Yang G ，Zhang H ，Tu G ，Du YE ，Wen S ，Xu L ，Tang X ，Tang S ，Yang L ，Cui X ，Liu M ... -  《-》

LncRNA-cCSC1 promotes cell proliferation of colorectal cancer through sponging miR-124-3p and upregulating CD44.

LncRNA-cCSC1 is highly expressed in colorectal cancer (CRC). The study was designed to evaluate the function and mechanism of lncRNA-cCSC1 in cell proliferation of CRC. RT-PCR was used to measure the expression levels of lncRNA-cCSC1 in CRC cell lines. CCK-8, colony formation, EdU staining, flow cytometry and Western blot were performed to examine the effect of interference with lncRNA-cCSC1 expression on cell proliferation. miR-124-3p and the target genes of miR-124-3p were investigated using bioinformatics analysis and verified by dual-luciferase reporter, RT-PCR and Western blot. Rescue experiments were carried out to confirm the role of miR-124-3p in cell proliferation of CRC. Our results showed that cell proliferation of CRC was promoted by lncRNA-cCSC1 upregulation and inhibited by lncRNA-cCSC1 downregulation. In addition, miR-124-3p is predicted to be the target of lncRNA-cCSC1 and is negatively correlated with lncRNA-cCSC1. Moreover, the addition of miR-124-3p mimics or inhibitor reversed the effects induced by lncRNA-cCSC1 overexpression or silencing on cell proliferation of CRC. Additionally, lncRNA-cCSC1 regulated the expression level of CD44, a target gene of miR-124-3p. Finally, we studied the effects of the lncRNA-cCSC1/miR-124-3p axis on CD44. These results indicate that lncRNA-cCSC1 promotes cell proliferation of CRC through sponging miR-124-3p and upregulating CD44.

Zhang HR ，Wu SY ，Fu ZX 《-》

TUSC3 induces drug resistance and cellular stemness via Hedgehog signaling pathway in colorectal cancer.

Tumor suppressor candidate 3 (TUSC3) is a coding gene responsible for N-glycosylation of many critical proteins. TUSC3 gene plays an oncogenic role in colorectal cancer (CRC), however, the role of TUSC3 in drug resistance of CRC is still unclear. The aim of this study is to investigate the biological function and molecular mechanism of TUSC3 in CRC drug resistance. The expression of TUSC3 in CRC is positively correlated to tumor stage in 90 paired clinical samples, and negatively associated with overall survival and disease-free survival of CRC patients. In vitro, TUSC3 promotes the formation of stemness and induces the drug resistance to 5-fluorouracil and cis-dichlorodiammineplatinum(II) in CRC cells. The tissue microarray assay and bioinformatic analysis indicate that TUSC3 may promote the expression of CD133 and ABCC1 via Hedgehog signaling pathway. Treatment of Hedgehog signaling pathway agonist or inhibitor in TUSC3-silenced or TUSC3-overexpressed cells reverse the effects of TUSC3 in cellular stemness phenotype and drug resistance. Meanwhile, coimmunoprecipitation and immunofluorescence assays indicate a tight relationship between TUSC3 and SMO protein. Our data suggest that TUSC3 promotes the formation of cellular stemness and induces drug resistance via Hedgehog signaling pathway in CRC.

Ren Y ，Deng R ，Cai R ，Lu X ，Luo Y ，Wang Z ，Zhu Y ，Yin M ，Ding Y ，Lin J ... -  《-》

Comprehensive analysis of the long noncoding RNA expression profile and construction of the lncRNA-mRNA co-expression network in colorectal cancer.

Zhang Q ，Ding Z ，Wan L ，Tong W ，Mao J ，Li L ，Hu J ，Yang M ，Liu B ，Qian X ... -  《-》