Silencing LINC00511 inhibits cell proliferation, migration, and epithelial-mesenchymal transition via the PTEN-AKT-FOXO1 signaling pathway in lung cancer

AKBA inhibits radiotherapy resistance in lung cancer by inhibiting maspin methylation and regulating the AKT/FOXO1/p21 axis

Acetyl-keto-b-boswellic acid (AKBA) functions in combating human malignant tumors, including lung cancer. However, the function of AKBA in regulating the radioresistance of lung cancer and its underlying mechanism still need to be elucidated. Radiation-resistant lung cancer cells (RA549) were established. Quantitative real-time polymerase chain reaction (QRT-PCR) and Western blot were employed to examine the messenger RNA (mRNA) and protein expressions. After being treated with AKBA and different doses of X-ray, cell proliferation and survival were examined using colony formation assay and cell-counting kit-8 (CCK-8) assay. The cellular localization of Forkhead box 1 (FOXO1) was measured by immunofluorescence (IF). Flow cytometry was employed to analyze cell cycle and apoptosis. In addition, in vivo experiment was performed to determine the effect of AKBA on the sensitivity of tumors to radiation. Herein, we found that AKBA could enhance the radiosensitivity in RA549, suppress cell proliferation, induce cell apoptosis and arrest cell cycle. It was observed that maspin was lowly expressed and hypermethylated in RA549 cells compared to that in A549 cells, while these changes were all eliminated by AKBA treatment. Maspin knockdown could reverse the regulatory effects of AKBA on radioresistance and cellular behaviors of RA549 cells. In addition, we found that AKBA treatment could repress the phosphorylation of Serine/Threonine Kinase (AKT), and FOXO1, increase the translocation of FOXO1 and p21 level in RA549 cells, which was abolished by maspin knockdown. Moreover, results of tumor xenograft displayed that AKBA could enhance the sensitivity of tumor to radiation through the maspin/AKT/FOXO1/p21 axis. We discovered that AKBA enhanced the radiosensitivity of radiation-resistant lung cancer cells by regulating maspin-mediated AKT/FOXO1/p21 axis.

Circ_0000189 Promotes the Malignancy of Glioma Cells via Regulating miR-192-5p-ZEB2 Axis

Background

Some recent studies have reported the role of circular RNAs (circRNAs) in modulating the tumorigenesis of human malignancies. Nevertheless, the expression characteristics, biological functions, and regulatory mechanism of circ_0000189 in glioma are unclear.

Methods

Quantitative real-time polymerase chain reaction (qRT-PCR) was utilized to detect the expression levels of circ_0000189, miR-192-5p, and ZEB2 mRNA in glioma tissues and cells. The association between the expression of circ_0000189 and the clinicopathological indicators and the features of magnetic resonance imaging (MRI) images of glioma patients were analyzed. Western blot was utilized to evaluate ZEB2 expression and epithelial-mesenchymal transition (EMT-)-related proteins (E-cadherin, N-cadherin, as well as Vimentin) in glioma cells. Cell proliferation was assessed employing cell counting kit-8 (CCK-8) and EdU experiments. Flow cytometry was used to detect the apoptotic rate of the cells. Cell migration and invasion were accessed employing Transwell assay. Moreover, dual luciferase reporter gene assay and RNA immunoprecipitation assay were employed to investigate the targeting relationship between miR-192-5p and circ_0000189, miR-192-5p, and ZEB2. Subcutaneous tumorigenesis experiment and lung metastasis experiment in nude mice were conducted to verify the regulatory function of circ_0000189 on the proliferation and metastasis of glioma cells in vivo.

Results

circ_0000189 was markedly overexpressed in glioma tissues and cell lines. Its high expression was associated with poor clinical pathological indicators and adverse MRI signs. Gain-of-function experiments and loss-of-function experiments confirmed that circ_0000189 overexpression facilitated the proliferation and migration, as well as invasion of glioma cells, and suppressed apoptosis, and facilitated epithelial-mesenchymal transition (EMT) process. Compared to the control group, knocking down circ_0000189 suppressed the malignant phenotypes of glioma cells both in vivo and in vitro. Working as a competitive endogenous RNA, circ_0000189 directly targeted miR-192-5p, and repressed its expression, and circ_0000189 positively modulated ZEB2 expression indirectly via repressing miR-192-5p.

Conclusion

circ_0000189 facilitates the progression of glioma by modulating miR-192-5p/ZEB2 axis.

The role of long intergenic noncoding RNA 00511 in malignant tumors: a meta-analysis, database validation and review

Increasing studies suggested that long intergenic noncoding RNA 00511 (LINC00511) could facilitate the progression of various malignancies and correlates with prognosis of patients with malignant tumors. However, its clinical significance is still not completely clarified. Therefore, we performed a meta-analysis and bioinformatics analysis to further evaluate the correlation of LINC00511 expression level with prognosis and metastasis in patients with tumors. The pooled hazard ratio (HR) with 95% confidence interval (CI) was used to evaluate the prognostic significance of LINC00511 expression level. The pooled odds ratio (OR) with 95% CI was applied to assess the association between LINC00511 expression level and tumor metastasis. A total of 12 studies involving 1040 tumor patients were included in this meta-analysis. The pooled analyses suggested that higher LINC00511 expression level correlated with worse overall survival (OS) (HR = 1.93, 95% CI 1.49–2.49, P < 0.001) and higher incidence of lymph node metastasis (OR = 3.07, 95% CI 2.23–4.23, P < 0.001). Additionally, bioinformatics analysis based on TCGA datasets also showed that increased LINC00511 expression level may predict poor OS and disease-free survival (DFS) in patients with malignant tumors. Taken together, our finding suggested that high LINC00511 expression level may be correlated with poor prognosis and high incidence of metastasis. Nevertheless, further large-scale and high-quality studies are needed to validate our findings.

LncRNA LINC00511 Acts as an Oncogene in Colorectal Cancer via Sponging miR-29c-3p to Upregulate NFIA

Background

Colorectal cancer (CRC), characterized by high mortality and incidence rate, is one of the most common types of rectum tumors in the gastrointestinal tract worldwide. An increasing number of investigations indicated that long noncoding RNAs (lncRNAs) have been implicated in the growth of a wide range of cancers. Although it has obtained general acceptance that lncRNA LINC00511 plays a significant role in numerous cancers, the regulatory mechanism of LINC00511 in CRC still needs to be explored.

Materials and Methods

Bioinformatics analysis and a wide range of experiments of sphere formation assay, cell proliferation assay, RT-qPCR, colony formation assay, Transwell assay and Western blot assays investigated the function and mechanism of LINC00511 in CRC tissues and cells.

Results

Our results manifested that the expression level of LINC00511 was obviously upregulated in CRC tissues and cells and it accelerated CRC development through facilitating cell proliferation, metastasis and stemness. Molecular mechanism exploration uncovered that LINC00511 acted as a ceRNA competing with NFIA to bind with miR-29c-3p. Through rescue experiments, we discovered that NFIA upregulation partly counteracted the inhibitive effect induced by LINC00511 silencing on CRC progression.

Conclusion

These results revealed that LINC00511 participated in the progression of CRC by targeting the LINC00511/miR-29c-3p/NFIA axis, indicating that LINC00511 may be a potential therapeutic target for CRC treatment.

Prognostic significance of long intergenic non-protein-coding RNA 511expression in malignant tumors: A systematic review and meta-analysis

BACKGROUND

A growing number of studies have suggested that the Long intergenic noncoding RNA 00511 (LINC00511) is aberrantly expressed in multiple malignancies and is related to patient survival. Herein, we conducted a systematic review and meta-analysis to comprehensively evaluate the prognostic significance of LINC00511 in human malignancies.

METHODS

Eligible studies published by March 11, 2020 were identified in 4 electronic databases including PubMed, EMBASE, Web of Science, and the Chinese National Knowledge Infrastructure. Hazard ratios and 95% confidence intervals (CIs) were used to evaluate the prognostic significance of LINC00511 expression in malignant tumors. The association between LINC00511 expression and cancer clinicopathologic features were assessed using Odds ratios (ORs) and CIs.

RESULTS

A total of 13 studies, comprising 1,053 patients, were included in the meta-analysis. The calculated hazard ratio was 2.00 (95% CI: 1.59-2.52, P < .000), suggesting that higher LINC00511 expression could predict poorer overall survival in patients with malignancies. Additionally, our statistical analysis indicated that elevated LINC00511 expression closely associated with bigger tumors (OR = 2.92, 95% CI 1.65-5.18, P < .000), higher incidence of lymph node metastasis (OR = 3.46, 95% CI 2.11-5.66, P < .000) and distant metastasis (OR = 2.40, 95% CI 1.14-5.05, P = .02), poorer differentiation (OR = 1.55, 95% CI 1.11-2.16, P = .01), as well as more advanced TNM stage (OR = 3.90, 95% CI 2.70-5.63, P < .000).

CONCLUSIONS

High LINC00511 expression may predict unfavorable prognosis in patients with malignancies. It should be further explored as a potential prognostic and therapeutic biomarker for human cancer.

Highly penetrating nanobubble polymer enhances LINC00511-siRNA delivery for improving the chemosensitivity of triple-negative breast cancer

Ultrasound-mediated nanobubble destruction (UMND), which can utilize the physical energy of ultrasound irradiation to improve the transfer efficiency to target cells is becoming one of the most promising carriers for gene delivery. The purpose of this study was to establish cell-penetrating peptide (CPP)-loaded nanobubbles (CNBs) connected with long intergenic nonprotein coding RNA 00511-small interfering RNA (LINC00511-siRNA) and evaluate its feasibility for improving the chemosensitivity of triple-negative breast cancer in vitro. First, fluorescence imaging confirmed the loading of siLINC00511 on CNBs, and the CNBs-siLINC00511 were characterized by the Zetasizer Nano ZS90 analyzer and transmission electron microscopy. Next, cell counting kit 8 assay was used to detect the inhibitory activity of cisplatin on the proliferation of MDA-MB-231 cells, and the 50% inhibition concentration value before and after transfer was calculated. Finally, the silencing effect of siLINC00511 was evaluated in vitro using an apoptosis assay, transwell assay, real time-PCR and western blotting. UMND combined with CNBs could effectively transfer the siRNA to MDA-MB-231 cells, thus evidently reducing the expression of LINC00511. Furthermore, inhibitory activity of cisplatin on MDA-MB-231 cells was enhanced after downregulation of LINC00511 expression. Downregulation of LINC00511 alters expression of cell cycle-related (CDK 6) and apoptosis-related (Bcl-2 and Bax) proteins in MDA-MB-231 cells. These results suggested that siRNA-CNBs may be an ideal vector for the treatment of tumors, with high efficiency RNA interference under the combined action of UMND. It may provide a new therapeutic method for triple negative breast cancer.

LINC00511 as a prognostic biomarker for human cancers: a systematic review and meta-analysis

BACKGROUND

Long intergenic non-coding RNA 00511 (LINC00511) is highly expressed in diverse cancers and has a correlation with poor clinical outcomes for cancer patients. In view of contradictory data among published data, we aim to evaluate the prognostic role of LINC00511 for cancer patients.

METHODS

In the present study, a meta-analysis of related studies has been performed to investigate the prognostic significance of LINC00511 in cancer patients. Relevant studies published before December 22, 2019 were systematically searched online in PubMed, EMBASE, Web of Science, and the Cochrane Library databases. The relationship between LINC00511 expression and cancer patients' survival, including overall survival (OS), disease-free survival (DFS)/relapse-free survival (RFS) and progression-free survival (PFS), was evaluated using pooled hazard ratios (HRs) with their corresponding 95% confidence intervals (CIs). The association between LINC00511 expression and clinicopathological features was assessed using odd ratios (ORs) and their corresponding 95% CIs.

RESULTS

A total of 14 eligible studies with 1883 patients were enrolled in the present meta-analysis. The results demonstrated that elevated expression of LINC00511 was significantly associated with poor OS (HR = 2.62; 95% CI: 2.00-3.45; p <  0.001), PFS (HR = 1.80; 95% CI: 1.29-2.51; p = 0.001) and DFS/RFS (HR = 2.90; 95% CI: 1.04-8.12; p = 0.04). Additionally, High LINC00511 expression was associated with large tumor size (OR = 3.10; 95% CI: 1.97-4.86; p <  0.00001), lymph node metastasis (OR = 3.11; 95% CI: 2.30-4.21; p <  0.00001), advanced clinical stage (OR = 3.95; 95% CI: 2.68-5.81; p <  0.00001), distant metastasis (OR = 2.39; 95% CI: 1.16-4.93; p = 0.02), and disease recurrence (OR = 4.62; 95% CI: 2.47-8.65; p <  0.00001). Meanwhile, no correlation was found between LINC00511 expression and age, gender, and histological grade. These findings were consolidated by the results of bioinformatics analysis.

CONCLUSIONS

Based on our findings, LINC00511 may serve as a novel prognostic biomarker for cancer patients.

Long intergenic non-coding RNA 511 correlates with improved prognosis, and hinders osteosarcoma progression both in vitro and in vivo

Background

This study aimed to investigate the correlation of long intergenic non‐coding RNA 511 (LINC00511) with clinicopathological characteristics and overall survival (OS) in osteosarcoma patients and to explore its function in osteosarcoma in vitro and in vivo.

Methods

Tumor tissues and adjacent tissues from 45 osteosarcoma patients were acquired, and LINC00511 expression was detected. In vitro, LINC00511 expression was detected in osteosarcoma cell lines and osteoblast cell line. LINC00511 overexpression‐treated (OE‐LINC00511) and nonsense overexpression‐treated (OE‐control) MG‐63 and Saos‐2 cells were cultured, followed by the assessment of cell proliferation, apoptosis, migration, and invasion. In vivo, tumor weight and volume were measured in OE‐LINC00511 and OE‐control xenografted mice.

Results

LINC00511 expression was decreased in tumor tissues compared with adjacent tissues (P < .001), and its high expression correlated with increased tumor cell necrosis rate to neoadjuvant chemotherapy (P = .025) and prolonged OS (P = .010). In vitro, LINC00511 expression was decreased in osteosarcoma cell lines (including MG‐63, U‐2OS, Saos‐2, and HOS) compared with osteoblast cell line (All P < .001). Cell proliferation was decreased at 48 hours (Both P < .01) and 72 hours (Both P < .001) (in MG‐63 and Saos‐2 cells); cell apoptosis was increased (P < .05) (in Saos‐2 cells); cell migration and invasion were decreased (All P < .01) (in MG‐63 cells and Saos‐2 cells) in OE‐LINC00511 compared with OE‐control. In vivo, tumor volume was reduced at week 4 (P < .001), week 5 (P < .001), week 6 (P < .001) in OE‐LINC00511 compared with OE‐control. Tumor weight was declined in OE‐LINC00511 than OE‐control (P < .001).

Conclusions

LINC00511 acts as a potential biomarker and therapeutic option for osteosarcoma.