LINC01087 Promotes the Proliferation, Migration, and Invasion of Thyroid Cancer Cells by Upregulating PPM1E

Knockdown of LINC01087 inhibits gastric cancer malignant behavior by regulating the miR-135a-5p/CAAP1 axis

Long noncoding RNAs play important roles in the occurrence and development of many malignant cancers. This study focuses on the effects of LINC01087 on gastric cancer and its underlying mechanism. In the present study, LINC01087 and CAAP1 were found to be upregulated, and miR-135a-5p was diminished in gastric cancer specimens and cells. Inhibition of LINC01087 resulted in cell proliferation inhibition and induced cell apoptosis through the intrinsic apoptosis signaling pathway, as evidenced by the activation of caspase-3 and caspase-9. An investigation of the signaling pathway revealed that the effects on proliferation and apoptosis following LINC01087 knockdown were mediated by suppression of CAAP1. Furthermore, application of a miR-135a-5p inhibitor or overexpression of CAAP1 could attenuate the apoptotic effect achieved by LINC01087 inhibition, confirming the involvement of miR-135a-5p/CAAP1 signaling in the occurrence of gastric cancer. In conclusion, the LINC01087/miR-135a-5p/CAAP1 axis modulates gastric cancer tumorigenesis and pathogenesis and presents new insight into gastric cancer targeted therapy.

Systematic Investigation of the Diagnostic and Prognostic Impact of LINC01087 in Human Cancers

(1) Background: Long non-coding RNAs may constitute epigenetic biomarkers for the diagnosis, prognosis, and therapeutic response of a variety of tumors. In this context, we aimed at assessing the diagnostic and prognostic value of the recently described long intergenic non-coding RNA 01087 (LINC01087) in human cancers. (2) Methods: We studied the expression of LINC01087 across 30 oncological indications by interrogating public resources. Data extracted from the TCGA and GTEx databases were exploited to plot receiver operating characteristic curves (ROC) and determine the diagnostic performance of LINC01087. Survival data from TCGA and KM-Plotter directories allowed us to graph Kaplan-Meier curves and evaluate the prognostic value of LINC01087. To investigate the function of LINC01087, gene ontology (GO) annotation and Kyoto Encyclopedia of Gene and Genomes (KEGG) enrichment analyses were performed. Furthermore, interactions between LINC01087 and both miRNA and mRNA were studied by means of bioinformatics tools. (3) Results: LINC01087 was significantly deregulated in 7 out of 30 cancers, showing a predominant upregulation. Notably, it was overexpressed in breast (BC), esophageal (ESCA), and ovarian (OV) cancers, as well as lung squamous cell carcinoma (LUSC), stomach adenocarcinoma (STAD), and uterine carcinosarcoma (UCS). By contrast, LINC01087 displayed downregulation in testicular germ cell tumors (TGCT). ROC curve analyses identified LINC01087 as a potential diagnostic indicator in BC, ESCA, OV, STAD, and TGCT. Moreover, high and low expression of LINC01087 predicted a favorable prognosis in BC and papillary cell carcinoma, respectively. In silico analyses indicated that deregulation of LINC01087 in cancer was associated with a modulation of genes related to ion channel, transporter, and peptide receptor activity. (4) Conclusions: the quantification of an altered abundance of LINC01087 in tissue specimens might be clinically useful for the diagnosis and prognosis of some hormone-related tumors, including BC, OV, and TGCT, as well as other cancer types such as ESCA and STAD. Moreover, our study revealed the potential of LINC01087 (and perhaps other lncRNAs) to regulate neuroactive molecules in cancer.