Long non‐coding RNA LINC01207 promotes prostate cancer progression by downregulating microRNA ‐1972 and upregulating LIM and SH3 protein 1

Analysis of Human microRNA Expression Profiling During Diquat-Induced Renal Proximal Tubular Epithelial Cell Injury

Background

We established a diquat-induced human kidney-2 cells (HK-2 cells) apoptosis model in this study to identify differentially expressed microRNAs (miRNAs) and signaling pathways involved in diquat poisoning via gene sequencing and bioinformatics analysis and explored the related therapeutic benefits.

Methods

The effects of diquat on the viability and apoptosis of HK-2 cells were explored using the CCK-8 and Annexin V-FITC/PI double staining methods. Total RNAs were extracted using the TRizol method and detected by Illumina HiSeq 2500. Bioinformatics analysis was performed to explore differentially expressed (DE) miRNAs, their enriched biological processes, pathways, and potential target genes. The RT-qPCR method was used to verify the reliability of the results.

Results

Diquat led to HK-2 cell injury and apoptosis played an important role, hence an HK-2 cell apoptosis model in diquat poisoning was established. Thirty-six DE miRNAs were screened in diquat-treated HK-2 cells. The enriched biological process terms were mainly cell growth, regulation of apoptotic signaling pathway, extrinsic apoptotic signaling pathway, and Ras protein signal transduction. The enriched cellular components were mainly cell-cell junction, cell-substrate junction, ubiquitin ligase complex, and protein kinase complex. The enriched molecular functions were mainly Ras GTPase binding, ubiquitin-like protein transferase activity, DNA-binding transcription factor binding, ubiquitin-protein transferase activity, nucleoside-triphosphatase regulator activity, transcription coactivator activity, and ubiquitin-like protein ligase binding. Signaling pathways such as MAPK, FoxO, Ras, PIK3-Akt, and Wnt were also enriched.

Conclusion

These findings aid in understanding the mechanisms of diquat poisoning and the related pathways, where DE miRNAs serve as targets for gene therapy.

Salivary Extracellular MicroRNAs for Early Detection and Prognostication of Esophageal Cancer: A Clinical Study

BACKGROUND & AIMS

Early detection of esophageal squamous cell carcinoma (ESCC) will facilitate curative treatment. We aimed to establish a microRNA (miRNA) signature derived from salivary extracellular vesicles and particles (EVPs) for early ESCC detection and prognostication.

METHODS

Salivary EVP miRNA expression was profiled in a pilot cohort (n = 54) using microarray. Area under the receiver operator characteristic curve (AUROC) and least absolute shrinkage and selector operation regression analyses were used to prioritize miRNAs that discriminated patients with ESCC from controls. Using quantitative reverse transcription polymerase chain reaction, the candidates were measured in a discovery cohort (n = 72) and cell lines. The prediction models for the biomarkers were derived from a training cohort (n = 342) and validated in an internal cohort (n = 207) and an external cohort (n = 226).

RESULTS

The microarray analysis identified 7 miRNAs for distinguishing patients with ESCC from control subjects. Because 1 was not always detectable in the discovery cohort and cell lines, the other 6 miRNAs formed a panel. A signature of this panel accurately identified patients with all-stage ESCC in the training cohort (AUROC = 0.968) and was successfully validated in 2 independent cohorts. Importantly, this signature could distinguish patients with early-stage (stage Ⅰ/Ⅱ) ESCC from control subjects in the training cohort (AUROC = 0.969, sensitivity = 92.00%, specificity = 89.17%) and internal (sensitivity = 90.32%, specificity = 91.04%) and external (sensitivity = 91.07%, specificity = 88.06%) validation cohorts. Moreover, a prognostic signature based on the panel was established and efficiently predicted the high-risk cases with poor progression-free survival and overall survival.

CONCLUSIONS

The salivary EVP-based 6-miRNA signature can serve as noninvasive biomarkers for early detection and risk stratification of ESCC. Chinese Clinical Trial Registry, ChiCTR2000031507.

Relationship of micro-RNA, mRNA and eIF Expression in Tamoxifen-Adapted MCF-7 Breast Cancer Cells: Impact of miR-1972 on Gene Expression, Proliferation and Migration

Background: Tamoxifen-adapted MCF-7-Tam cells represent an in-vitro model for acquired tamoxifen resistance, which is still a problem in clinics. We here investigated the correlation of microRNA-, mRNA- and eukaryotic initiation factors (eIFs) expression in this model. Methods: MicroRNA- and gene expression were analyzed by nCounter and qRT-PCR technology; eIFs by Western blotting. Protein translation mode was determined using a reporter gene assay. Cells were transfected with a miR-1972-mimic. Results: miR-181b-5p,-3p and miR-455-5p were up-, miR-375, and miR-1972 down-regulated and are significant in survival analysis. About 5% of the predicted target genes were significantly altered. Pathway enrichment analysis suggested a contribution of the FoxO1 pathway. The ratio of polio-IRES driven to cap-dependent protein translation shifted towards cap-dependent initiation. Protein expression of eIF2A, -4G, -4H and -6 decreased, whereas eIF3H was higher in MCF-7-Tam. Significant correlations between tamoxifen-regulated miRNAs and eIFs were found in representative breast cancer cell lines. Transfection with a miR-1972-mimic reverses tamoxifen-induced expression for a subset of genes and increased proliferation in MCF-7, but reduced proliferation in MCF-7-Tam, especially in the presence of 4OH-tamoxifen. Migration was inhibited in MCF-7-Tam cells. Translation mode remained unaffected. Conclusions: miR-1972 contributes to the orchestration of gene-expression and physiological consequences of tamoxifen adaption.

LINC01207 promotes prostate cancer progression by sponging miR-1182 to upregulate AKT3

Prostate cancer (PC) is recognized as a common malignancy in male patients. Long non-coding RNA (lncRNA) has been implicated in the development of PC. Recently, long intergenic non-protein coding RNA 1207 (LINC01207) has been reported to regulate the carcinogenesis of multiple cancer types. However, its role in the progression of PC remains to be determined. The aim of the present study was to investigate the expression profile, clinicopathological implication and molecular mechanism of action of LINC01207 in the progression of PC. LINC01207 expression levels were compared between PC tumor and paired normal tissue samples from The Cancer Genome Atlas. The expression of LINC01207 was further analyzed in PC cell lines and a normal prostatic cell line. The role of LINC01207 in proliferation, migration and invasion of PC cells was examined using small interfering RNA-mediated silencing. Western blot analysis was used to investigate the changes in protein levels underlying the mechanism of action of LINC01207. The role of LINC01207 in tumorigenesis was evaluated in a xenograft model. LINC01207 was upregulated in PC tumor samples from TCGA data compared with paired normal tissue. LINC01207 expression was significantly increased in PC cells and tumor tissues compared with in normal prostate cells (RWPE1) and normal prostate tissues, respectively. Furthermore, LINC01207 silencing inhibited PC cell proliferation and colony formation and induced apoptosis. Mechanistic experiments showed that LINC01207 promoted carcinogenesis by sponging miR-1182 to regulate the protein levels of AKT3 in PC cell lines. Thus, the findings of the present study indicated that LINC01207 might play a role in the tumorigenesis of PC and may serve as a therapeutic target for PC treatment.

Long Noncoding Competing Endogenous RNA Networks in Pancreatic Cancer

Pancreatic cancer (PC) is a highly malignant disease characterized by insidious onset, rapid progress, and poor therapeutic effects. The molecular mechanisms associated with PC initiation and progression are largely insufficient, hampering the exploitation of novel diagnostic biomarkers and development of efficient therapeutic strategies. Emerging evidence recently reveals that noncoding RNAs (ncRNAs), including long ncRNAs (lncRNAs) and microRNAs (miRNAs), extensively participate in PC pathogenesis. Specifically, lncRNAs can function as competing endogenous RNAs (ceRNAs), competitively sequestering miRNAs, therefore modulating the expression levels of their downstream target genes. Such complex lncRNA/miRNA/mRNA networks, namely, ceRNA networks, play crucial roles in the biological processes of PC by regulating cell growth and survival, epithelial-mesenchymal transition and metastasis, cancer stem cell maintenance, metabolism, autophagy, chemoresistance, and angiogenesis. In this review, the emerging knowledge on the lncRNA-associated ceRNA networks involved in PC initiation and progression will be summarized, and the potentials of the competitive crosstalk as diagnostic, prognostic, and therapeutic targets will be comprehensively discussed.

FOXD1-AS1 promotes malignant behaviours of prostate cancer cells via the miR-3167/YWHAZ axis

Herein, the effect of long noncoding RNA forkhead box D1 antisense RNA 1 (FOXD1-AS1) on malignant phenotypes of prostate cancer (PCa) cells was investigated. FOXD1-AS1 presented high expression in PCa cells according to the results of RT-qPCR. As shown by cell counting kit-8 assays, colony formation assays, wound-healing assays, Transwell assays and flow cytometry analyses, silenced FOXD1-AS1 suppressed PCa cell viability, proliferation, migration and invasion and enhanced cell apoptosis. Additionally, FOXD1-AS1 was primarily localised in cytoplasm of PCa cells. RNA immunoprecipitation assays and luciferase reporter assays revealed that FOXD1-AS1 interacted with miR-3167 in PCa cells. MiR-3167 functioned as an anti-oncogene in PCa and miR-3167 overexpression suppressed cell proliferation while promoted cell apoptosis. Moreover, the downstream target of miR-3167 is mRNA YWHAZ. FOXD1-AS1 elevated the expression of YWHAZ by binding with miR-3167. The suppressive effect of miR-3167 on YWHAZ expression was reversed by FOXD1-AS1 overexpression. Furthermore, overexpressed YWHAZ reversed the suppressive effect of FOXD1-AS1 deficiency on malignant behaviours of PCa cells. Overall, FOXD1-AS1 facilitates malignant phenotypes of PCa cells by up-regulating YWHAZ via miR-3167. The study first reveals the molecular mechanism of FOXD1-AS1 in PCa, suggesting that FOXD1-AS1 and its downstream molecules might be prognostic biomarkers before medical treatment.

miR-199a-3p plays an anti-tumorigenic role in lung adenocarcinoma by suppressing anterior gradient 2

Previous studies have explored the association between protein-coding genes and microRNAs (miRNAs) in lung adenocarcinoma (LUAD). However, the influence of the miR-199a-3p/anterior gradient 2 (AGR2) axis in LUAD has not yet been fully explored. Therefore, this study aimed to examine the underlying roles of AGR2 and miR-199a-3p in the development of LUAD. The expression levels of miR-199a-3p and AGR2 in LUAD tissues and cells were detected via quantitative reverse transcription-polymerase chain reaction (qRT-PCR). A luciferase assay was also performed to identify the interaction between AGR2 and miR-199a-3p. Moreover, the cell counting kit 8 (CCK-8), 5'-bromo-2'-deoxyuridine (BrdU), and adhesion assays were used along with flow cytometry to verify the malignancy of LUAD in vitro, while a xenograft tumor assay was performed to confirm the tumor growth in vitro. The findings showed a decrease in the expression of miR-199a-3p in LUAD. Additionally, miR-199a-3p overexpression inhibited the growth of LUAD cells in vitro and in vivo, while elevating the apoptosis rate of the cells. AGR2 knockdown had the same effect in the cells as that of miR-199a-3p overexpression. It was also found that miR-199a-3p directly targeted AGR2 in LUAD cells to suppress tumorigenesis. In conclusion, this study suggests that miR-199a-3p plays an anti-tumorigenic role in LUAD by targeting AGR2. Moreover, our study provides insights into the development of novel therapeutic targets for the treatment of LUAD.

Downregulation of MIAT reduces the proliferation and migratory and invasive abilities of retinoblastoma cells by sponging miR-665 and regulating LASP1

Long non-coding RNAs (lncRNAs) can function as onco-lncRNAs in several types of human cancer, including retinoblastoma (Rb). The present study investigated the potential role and regulatory mechanism of the lncRNA myocardial infarction-associated transcript (MIAT) in Rb. To do so, the expression levels of MIAT, microRNA (miR)-665, and LIM and SH3 protein 1 (LASP1) in Rb tissues from patients or Rb cells were analysed using reverse transcription quantitative PCR. The interactions between miR-665 and MIAT/LASP1 were confirmed by the dual-luciferase reporter assay. MTT, Transwell (to assess migration and invasion) and western blotting assays were used to explore the functions of the MIAT/miR-665/LASP1 axis on Rb progression in vitro. The results of the present study indicated that MIAT targeted miR-665. In Rb tissues and cell lines, high expression of MIAT was observed, whereas miR-665 was downregulated in Rb tissues. Furthermore, the proliferation and migratory and invasive abilities of Rb Y79 and HXO-RB44 cells were decreased following MIAT downregulation or miR-665 overexpression. In addition, LASP1 was identified as a target gene of miR-665. Both the decreased expression of miR-665 and the elevated expression of LASP1 reversed the suppressive effects of MIAT knockdown on the proliferation and migratory and invasive abilities of Y79 cells. Furthermore, MIAT silencing attenuated the development of Rb by regulating the miR-665/LASP1 axis. Taken together, these findings suggested that MIAT may be considered as a possible therapeutic target for Rb.

Long non-coding RNA LINC01207 promotes cell proliferation and migration but suppresses apoptosis and autophagy in oral squamous cell carcinoma by the microRNA-1301-3p/lactate dehydrogenase isoform A axis

Long noncoding RNAs (lncRNAs) have been reported to participate in the progression of various cancers, including oral squamous cell carcinoma (OSCC). This study aims to find out whether lncRNA LINC01207 regulates the progression of OSCC. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) was conducted to evaluate gene expression in OSCC cells and tissues. Cell viability, proliferation, migration, apoptosis, and autophagy were detected using Cell Counting Kit-8 (CCK-8), colony formation, Transwell assays, flow cytometry, and western blot analysis. Luciferase reporter and RNA immunoprecipitation (RIP) assays were conducted to assess the interactions among genes. We found that LINC01207 was overexpressed in OSCC cells and tissues. LINC01207 silencing inhibited OSCC cell proliferation and migration but promoted apoptosis and autophagy, and LINC01207 overexpression had an opposite result. LINC01207 interacted with microRNA-1301-3p (miR-1301-3p) while lactate dehydrogenase isoform A (LHDA) was targeted by miR1301-3p. Effects caused by LINC01207 downregulation on OSCC cells were reversed by overexpression of LDHA. Overall, LINC01207 promotes OSCC progression via the miR-1301-3p/LDHA axis

CTCF-induced upregulation of LINC01207 promotes gastric cancer progression via miR-1301-3p/PODXL axis

BACKGROUND

Long non coding RNAs (lncRNAs) have been validated to be involved in the complicated biological processes during tumor progression. LINC01207 has been identified as an oncogene in several cancer types. However, the function of LINC01207 and its underlying molecular mechanism in gastric cancer (GC) are poorly understood.

METHODS

The expression level of LINC01207, miR-1301-3p and PODXL mRNA was detected in GC tissues and cells by RT-qPCR. The level of PODXL protein was examined by western blot. Colony formation assay, EdU assay, TUNEL assay, caspase-3 activity test and transwell assays were carried out to analyze the effect of LINC01207 on GC cell proliferation, apoptosis, migration and invasion. The interaction between RNAs was confirmed by luciferase reporter assay, RNA pull-down assay and RIP assay.

RESULTS

LINC01207 was expressed at high level in GC tissues and cells. Silencing of LINC01207 impaired GC cell proliferation, migration and invasion but promoted cell apoptosis. Mechanistically, LINC01207 acted as a ceRNA by sponging miR-1301-3p to upregulate PODXL. Besides, miR-1301-3p silencing or PODXL overexpression could abolish the inhibitory effect of LINC01207 knockdown on GC cell growth and migration. CCCTC-binding factor (CTCF) could transcriptionally activate LINC01207 in GC cells.

CONCLUSIONS

CTCF-induced activation of LINC01207 contributes to GC progression through regulating miR-1301-3p/PODXL axis.

Long Intergenic Non-Protein Coding RNA 519 Promotes the Biological Activities of Tongue Squamous Cell Carcinoma by Sponging microRNA-876-3p and Consequently Upregulating MACC1

Purpose

Long intergenic non-protein coding RNA 519 (LINC00519) promotes the development of lung squamous cell carcinoma. In this study, we detected the expression of LINC00519 in tongue squamous cell carcinoma (TSCC) and examined its clinical significance. Additionally, the regulatory effects of LINC00519 on behaviors of TSCC tumor cells were explored through functional experiments. Finally, mechanistic studies were performed to elucidate the molecular events underlying the tumor-promoting actions of LINC00519 in TSCC.

Materials and Methods

The expression of LINC00519 in TSCC tissues and cell lines was determined using quantitative reverse transcription-polymerase chain reaction. Cell counting kit-8 assay, flow cytometric analysis, cell migration and invasion assays and xenograft tumor model analyses were used to detect TSCC cell proliferation, apoptosis, migration and invasion and in vivo tumor growth, respectively. Mechanistic studies were performed using bioinformatics analysis, RNA immunoprecipitation assay, luciferase reporter assay and rescue experiments.

Results

LINC00519 was overexpressed in both TSCC tissues and cell lines. A high LINC00519 level was associated with poor overall survival in patients with TSCC. In vitro, LINC00519 played cancer-promoting roles in TSCC progression by facilitating cell proliferation, migration and invasion and restraining cell apoptosis. In vivo, LINC00519 downregulation resulted in decreased TSCC tumor growth. Mechanistically, LINC00519 acted as a competing endogenous RNA for microRNA-876-3p (miR-876-3p), which directly targets metastasis associated with colon cancer-1 (MACC1), in TSCC cells. LINC00519 upregulated the expression of MACC1 in TSCC cells by sequestering miR-876-3p. Rescue experiments further affirmed that miR-876-3p inhibition or MACC1 overexpression mitigated the inhibitory influences of LINC00519 depletion on cell proliferation, migration and invasion and neutralized the promoting actions of LINC00519 knockdown on cell apoptosis in TSCC.

Conclusion

LINC00519 aggravated the oncogenicity of TSCC by regulating the miR-876-3p/MACC1 axis. Our findings suggest that the LINC00519/miR-876-3p/MACC1 pathway may be an underlying therapeutic target in TSCC.