<p>The Down-Regulation of lncRNA PCAT18 Promotes the Progression of Gastric Cancer via MiR-107/PTEN/PI3K/AKT Signaling Pathway</p>

Abstract

Purpose: LncRNAs are important regulators in cancers. In this study, we investigated the role of lncRNA PCAT18 in gastric cancer (GC). Patients and Methods: The level of PCAT18 in GC tissues and cells was determined by qRT-PCR. The cellular behaviors of GC cells with knockdown or overexpression of PCAT18 were respectively detected by CCK-8 assays, colony formation assays, flow cytometry and Western blot. A GC mice model was established by subcutaneous injection of MGC-803 and HGC-27 cells with the knockdown or overexpression of PCAT18. The tumor size and weight were measured, and IHC was performed to determine ki-67 level. Predicted by bioinformatics software and confirmed by dual-luciferase reporter assay, PCAT18 was involved in miR-107/PTEN axis, thus, the expression of and relationship among PCAT18, miR-107 and PTEN pathway were explored in clinical cases and GC cell lines. Rescue assay was performed in GC cells by co-transfection with miR-107 mimic or PCAT18. The PTEN/ PI3K/AKT pathway was then detected by Western blot. Results: PCAT18 was down-regulated in GC tissues and cells, and it had a significant diagnostic value for GC. The expression of PCAT18 was highly associated with tumor size, and PCAT18 was found to inhibit GC growth in vitro and in vivo. It was also found that PCAT18 was involved in PTEN/PI3K/AKT signaling pathway through targeting miR-107. Conclusion: PCAT18 inhibits the progression of GC via miR-107/PTEN/PI3K/AKT signaling pathway. Additionally, PCAT18 is possibly a promising target for treatment of GC.

<p>Long Noncoding RNA PCAT18 Upregulates SPRR3 to Promote Colorectal Cancer Progression by Binding to miR-759</p>

“…21 PCAT18 has been found to sponge miR-107 and miR-135b in gastric cancer. 11,12 We also found that PCAT18 was expressed in the cytoplasm of CRC cells, suggesting it may be also a miRNA sponge. Through bioinformatics prediction, we identified miR-759 as the target.…”

“…17 Previously, PCAT18 was identified as a tumor suppressor in gastric cancer. 12 , 18 However, the role of PCAT18 in other cancers, including CRC, remains fully unclear. In this work, we showed that PCAT18 was highly expressed in CRC tissues.…”

“… 11 Another study also confirms the inhibitory role of PCAT18 in gastric cancer. 12 Nevertheless, the role of PCAT18 in CRC remains unclear. In this research, PCAT18 expression was found to be raised in CRC tissues and cells.…”

High miR-324-5p expression predicts unfavorable prognosis of gastric cancer and facilitates tumor progression in tumor cells

“…PTEN is a widely known as a tumor suppressor, and its mutation or downregulation has been commonly observed in various human cancers, including GCa [ 33 , 34 ]. The most important function of PTEN is acting as an inhibitor of the PI3K/AKT signaling pathway, which is a pivotal signal during cancer cell growth [ 35 ]. Numerous key molecules are involved in GCa progression through the PI3K/AKT signaling pathway [ 36 , 37 ].…”

PCAT18, as a novel differentially regulated long noncoding RNA in adult acute myeloid leukemia patients revealed by next‐generation sequencing

“…29 Moreover, PCAT18 as a tumor suppressor gene in gastric cancer by the PTEN/PI3K/AKT signaling pathway. 30 However, its function in hematologic malignancies remained unknown. Notably, we found that PCAT18 was considerably overexpressed in AML patient samples.…”