Long Non-coding RNA Colon Cancer-Associated Transcript-1 Promotes Migration, Invasion, and Epithelial Mesenchymal Transition of Lung Adenocarcinoma by Suppressing miR-219-1

Long non-coding RNA CCAT1 acts as an oncogene to promote radiation resistance in lung adenocarcinoma: an epigenomics-based investigation

Long non-coding RNAs (lncRNAs) appear to be the crucial modulators in various processes and critically influence the oncogenesis. As one of the LncRNAs, LncRNA CCAT1 has been reported to be closely associated with the progression multiple cancers, but its role in modulating the radioresistance of lung adenocarcinoma (LUAD) remains unclear. In our present study, we screened the potential radioresistance related LncRNAs in LUAD based on the data from The Cancer Genome Atlas (TCGA) database. Data suggested that CCAT1 was abundantly expressed in LUAD and CCAT1 was significantly associated with poor prognosis and radioresistance. Moreover, our in vitro experiments showed that radiation treatment could trigger elevated expression of CCAT1 in the human LUAD cell lines. Further loss/gain-of-function investigations indicated that CCAT1 knockdown significantly inhibited cell proliferation, migration and promoted cell apoptosis in NCI-H1299 cells under irradiation, whereas CCAT1 overexpression in A549 cells yield the opposite effects. In summary, we identified the promoting role of CCAT1 in radioresistance of LUAD, which may provide a theoretical basis for radiotherapy sensitization of LUAD.

Sensitive Interrogation of Enhancer Activity in Living Cells on a Nanoelectroporation-Probing Platform

Enhancers involved in the upregulation of multiple oncogenes play a fundamental role in tumorigenesis and immortalization. Exploring the activity of enhancers in living cells has emerged as a critical path to a deep understanding of cancer properties, further providing important clues to targeted therapy. However, identifying enhancer activity in living cells is challenging due to the double biological barriers of a cell cytoplasmic membrane and a nuclear membrane, limiting the sensitivity and responsiveness of conventional probing methods. In this work, we developed a nanoelectroporation-probing (NP) platform, which enables intranuclear probe delivery for sensitive interrogation of enhancer activity in living cells. The nanoelectroporation biochip achieved highly focused perforation of the cell cytoplasmic membrane and brought about additional driving force to expedite the delivery of probes into the nucleus. The probes targeting enhancer activity (named "PH probe") are programmed with a cyclic amplification strategy and enable an increase in the fluorescence signals over 100-fold within 1 h. The platform was leveraged to detect the activity of CCAT1 enhancers (CCAT1, colon cancer-associated transcript-1, a long noncoding RNA that functions in tumor invasion and metastasis) in cell samples from clinical lung cancer patients, as well as reveal the heterogeneity of enhancers among different patients. The observations may extend the linkages between enhancers and cancer cells while validating the robustness and reliability of the platform for the assay of enhancer activity. This platform will be a promising toolbox with wide applicable potential for the intranuclear study of living cells.

LncRNA-CCAT1/miR-152-3p is involved in CSE-induced inflammation in HBE cells via regulating ERK signaling pathway

Emerging studies have noted that dysregulated long non-coding RNAs (lncRNAs) are implicated in the pathological processes of chronic obstructive pulmonary disease (COPD). LncRNA colon cancer-associated transcript 1 (CCAT1) plays well-defined roles in the inflammatory progression. The study aims to figure out the effect and regulatory mechanism of CCAT1 in the cigarette smoke induced inflammation in COPD. The results showed that CCAT1 was highly expressed in lung tissues of smokers with COPD compared with never-smokers without COPD. In human bronchial epithelial (HBE) cells, cigarette smoke extract (CSE) treatment led to an increase in CCAT1 expression in a dose- and time- dependent manner. Functional experiments showed that knockdown of CCAT1 amelioratedCSE-inducedinflammation. Mechanistically, CCAT1 directly targeted miR-152-3p, and miR-152-3p overexpression reversed the pro-inflammatory effects of CCAT1 on HBE cells. Subsequently, miR-152-3p was found to regulate ERK signaling pathway. PD98059, an ERK specific inhibitor, reversed miR-152-3p knockdown mediated inflammation in HBE cells. In addition, CCAT1 acted as a sponge for miR-152-3p to positively regulate ERK signaling pathway. Overall, current findings suggest that CCAT1 promoted inflammation by activating ERK signal pathway via sponging miR-152-3p in CSE-treated HBE cells. These results may provide a novel therapeutic target for alleviating cigarette smoke mediated airway inflammation.

Genetic Polymorphisms in microRNA Genes Targeting PI3K/Akt Signal Pathway Modulate Cervical Cancer Susceptibility in a Chinese Population

Polymorphisms in microRNA (miRNA) genes could influence the expression of miRNAs that regulate the PI3K/Akt signalling pathway and play crucial roles in cancer susceptibility. To investigate the association of single nucleotide polymorphisms (SNPs) in miRNA genes of PI3K/Akt with cervical intraepithelial neoplasia (CIN) and cervical cancer (CC), nine SNPs located in miRNA genes were selected for genotyping, and the association of these SNPs with CIN and CC risk was evaluated. A total of 1,402 participants were enrolled in the current study, including 698 healthy individuals in the control group, 431 patients with CC, and 273 patients with CIN. Nine SNPs in miRNA genes (rs107822 in miR-219a, rs10877887 in let-7i, rs2292832 in miR-149, rs353293 in miR-143, rs3746444 in miR-499, rs3803808 in miR-132, rs4078756 in miR-10b, rs629367 in let-7a, and rs7372209 in miR-26a) were genotyped using MassArray, and the association of these SNPs with CIN and CC were analysed. The results showed that the frequencies of rs107822 in miR-219a and rs2292832 in miR-149 were significantly different between the control and CC groups (p < 0.005). The C allele of rs107822 in miR-219a was associated with an increased risk of CC (OR = 1.29, 95%CI:1.09–1.54) whereas the C allele of rs2292832 in miR-149 was associated with a decreased risk of CC (OR = 0.77, 95%CI:0.64–0.92). The results of inheritance model analysis showed that the best-fit inheritance models for rs107822 and rs2292832 were log-additive. The 2CC + CT genotype of rs107822 could be a risk factor for CC when compared with the TT genotype (OR = 1.28, 95%CI:1.08–1.51). The 2CC + CT genotype of rs2292832 could be a protective factor against CC when compared with the TT genotype (OR = 0.76, 95%CI:0.64–0.92). However, no association of these SNPs with CIN was found in the current study. Our results suggest that rs107822 in the promoter region of miR-219a and rs2292832 in pre-miR-149 region are associated with the risk of CC.