Expression levels and associations of five long non‑coding RNAs in gastric cancer and their clinical significance

Abstract

Gastric cancer (GC) is a type of cancer that is commonly diagnosed worldwide due to a lack of early diagnostic, prognostic and therapeutic targets for this disease. The aim of the present study was to examine the expression levels of five long non-coding RNAs, namely PTPRG antisense RNA 1 (PTPRG-AS1), forkhead box P4 antisense RNA 1 (FOXP4-AS1), bladder cancer-associated transcript 2 (BLACAT2), ZXF2 and upregulated in colorectal cancer (UCC), to study their associations with patient characteristics and assess their prognostic efficacy, in order to determine the possibility of their application as GC biomarkers. The expression levels of long non-coding RNAs (lncRNAs) were determined by reverse transcription-quantitative PCR analysis of 61 pairs of GC tissues and adjacent healthy gastric mucosa tissues and GC cell lines. The Chi-square test was conducted to assess the associations of lncRNA expression levels with clinical characteristics of patients. The effect of UCC on GC cell proliferation was determined using in vitro functional experiments. The prognostic efficacy of FOXP4-AS1, BLACAT2 and UCC were examined in the Gene Expression Profiling Interactive Analysis database and those of PTPRG-AS1 were examined in the Kaplan Meier Plot database. Gene alteration frequencies of PTPRG-AS1 and BLACAT2 in GC were identified using the cBioPortal for Cancer Genomics. PTPRG-AS1, FOXP4-AS1, BLACAT2, ZXF2 and UCC were found to be upregulated in GC cell lines and GC tissues compared with adjacent normal tissues. PTPRG-AS1 and ZXF2 expression levels were associated with the expression status of the cell proliferation marker Ki67. UCC promoted the proliferation of GC cells in vitro and was associated with lymph node metastasis. Increased expression of FOXP4-AS1 indicated a favorable outcome in terms of disease-free survival, whereas high expression of PTPRG-AS1 was associated with poor survival rates for patients in different GC risk groups. BLACAT2 gene mutation was associated with poor disease-free survival outcome for patients with GC. The results suggest that PTPRG-AS1, FOXP4-AS1, BLACAT2, ZXF2 and UCC are potential biomarkers for the detection of GC at the molecular level and may be used as potential targets for GC therapy. The individual roles of these lncRNAs may be utilized for prognostic predictions.

Long Non-coding RNA PTPRG-AS1 Promotes Cell Tumorigenicity in Epithelial Ovarian Cancer by Decoying microRNA-545-3p and Consequently Enhancing HDAC4 Expression

“…PTPRG-AS1 is overexpressed in breast cancer [22], nasopharyngeal carcinoma [23], and gastric cancer [24]. Highly expressed PTPRG-AS1 is correlated with poor survival for patients with gastric cancer [24].…”

“…PTPRG-AS1 is overexpressed in breast cancer [22], nasopharyngeal carcinoma [23], and gastric cancer [24]. Highly expressed PTPRG-AS1 is correlated with poor survival for patients with gastric cancer [24]. PTPRG-AS1 functions as a cancer-promoting lncRNA in nasopharyngeal carcinoma [23] and gastric cancer [24], and is implicated in the regulation of many types of malignant processes.…”

“…Highly expressed PTPRG-AS1 is correlated with poor survival for patients with gastric cancer [24]. PTPRG-AS1 functions as a cancer-promoting lncRNA in nasopharyngeal carcinoma [23] and gastric cancer [24], and is implicated in the regulation of many types of malignant processes. However, the expression and function of PTPRG-AS1 in EOC has not been de ned.…”

Long non-coding RNA PTPRG-AS1 promotes cell tumorigenicity in epithelial ovarian cancer by decoying microRNA-545-3p and consequently enhancing HDAC4 expression

“…Regarding EOC, a substantial amount of evidence has established that various lncRNAs are differentially expressed and function as tumor-inhibiting or tumor-promoting factors in regulating tumorigenesis [15][16][17]. microRNAs (miRNAs) are a class of single-stranded, non-coding RNA transcripts comprising [17][18][19][20][21][22][23][24] nucleotides [18]. These short miRNAs bind to the 3′-untranslated region (3′-UTRs) of their target genes through miRNA-response elements by complete or incomplete complementary base pairing, which results in translation suppression or target mRNA degradation [19].…”

“…LncRNA PTPRG-AS1 deregulation has been reported to occur in breast cancer [22], nasopharyngeal carcinoma [23], and gastric cancer [24] and was identi ed as a critical modulator of cancer development.…”