CDKN2B-AS1 Exerts Oncogenic Role in Osteosarcoma by Promoting Cell Proliferation and Epithelial to Mesenchymal Transition

The Long Non-Coding RNA ANRIL in Cancers

ANRIL (Antisense Noncoding RNA in the INK4 Locus), a long non-coding RNA encoded in the human chromosome 9p21 region, is a critical factor for regulating gene expression by interacting with multiple proteins and miRNAs. It has been found to play important roles in various cellular processes, including cell cycle control and proliferation. Dysregulation of ANRIL has been associated with several diseases like cancers and cardiovascular diseases, for instance. Understanding the oncogenic role of ANRIL and its potential as a diagnostic and prognostic biomarker in cancer is crucial. This review provides insights into the regulatory mechanisms and oncogenic significance of the 9p21 locus and ANRIL in cancer.

Long noncoding RNA CDKN2B-AS1 silencing protects against esophageal cancer cell invasion and migration by inactivating the TFAP2A/FSCN1 axis

Esophageal cancer (EC) is the most aggressive malignancy in the gastrointestinal tract. Long noncoding RNA cyclin-dependent kinase inhibitor 2 B antisense RNA 1 (CDKN2B-AS1) is implicated in EC development. However, the specific mechanisms involved remain poorly defined. Therefore, this research aimed to explore the mechanism of action of CDKN2B-AS1 in EC. Quantitative real-time polymerase chain reaction was conducted to measure CDKN2B-AS1 expression in EC cells and western blotting was utilized to evaluate transcription factor AP-2 alpha (TFAP2A) and fascin actin-bundling protein 1 (FSCN1) expression. After gain-of-function and loss-of-function assays, cell proliferation, migration, invasion, apoptosis, and apoptosis-related protein expression were assessed using cell counting kit-8, scratch tests, Transwell assays, flow cytometry, and western blotting, respectively. The binding relationship between CDKN2B-AS1 and TFAP2A was assessed by RNA immunoprecipitation and RNA pull-down assays. The binding relationship between TFAP2A and FSCN1 was evaluated using dual-luciferase reporter and chromatin immunoprecipitation assays. Tumor xenografts from nude mice were used for in vivo verification. CDKN2B-AS1, TFAP2A, and FSCN1 were upregulated in EC cells. Mechanistically, CDKN2B-AS1 transcriptionally activated FSCN1 by recruiting TFAP2A to the FSCN1 promoter. Silencing CDKN2B-AS1 or TFAP2A suppressed EC cell proliferative, migrating, and invasive properties and augmented apoptosis. TFAP2A was bound to CDKN2B-AS1 and the FSCN1 promoter. Overexpression of TFAP2A or FSCN1 abolished the effects of CDKN2B-AS1-silencing on EC cell function. CDKN2B-AS1 silencing curtailed tumorigenesis in nude mice, which was nullified by the upregulation of TFAP2A or FSCN1. Our findings demonstrated the antioncogenic effects of silencing CDKN2B-AS1 in EC through inactivation of the TFAP2A/FSCN1 axis.

Significance of lncRNA CDKN2B-AS1 in Interventional Therapy of Liver Cancer and the Mechanism under Its Participation in Tumour Cell Growth via miR-199a-5p

Methods

Totally 34 LC patients admitted to our hospital between January 2020 and March 2021 (Obs group) and 32 healthy individuals over the same time span (Con group) were enrolled. CDKN2B-AS1 and miR-199a-5p in the two groups were PCR quantified, and their association and value for the diagnosis and therapy of LC were analyzed. In addition, purchased LC cells were adopted for in vitro assays, and the influences of CDKN2B-AS1 and miR-199a-5p on biological behaviours of LC cells were assessed through CCK-8, Transwell, and flow cytometry experiment, and their regulatory association was verified by the dual luciferase reporter (DLR) assay and rescue assay. And the autophagic protein expression was tested by the western blot to confirm the effect of both on the autophagic capacity of LC cells.

Results

CDKN2B-AS1 in LC cases presented high expression and dropped after therapy (P < 0.05), and the opposite situation of miR-199a-5p was found in the LC cases (P < 0.05). In vitro assays, after silencing of CDKN2B-AS1 and upregulation of miR-199a-5p, LC cells presented weaker viability, invasion and migration activities, and stronger apoptotic activity (all P < 0.05). The DLR assay revealed suppressed fluorescence activity of CDKN2B-AS1-WT by miR-199a-5p (P < 0.05). Moreover, according to the rescue assay, the impacts of silencing CDKN2B-AS1 on LC cells could be completely offset by silencing miR-199a-5p (P < 0.05). According to the clone formation and WB assay, the growth and autophagy of LC cells were under the regulation of CDKN2B-AS1 targeting miR-199a-5p (P < 0.05).

Conclusion

With high expression in LC cases, CDKN2B-AS1 is implicated in the development and progression of LC by suppressing cell autophagy through targeting miR-199a-5p.

Long non-coding RNAs: a valuable biomarker for metabolic syndrome

Long non-coding RNAs (lncRNAs) have become important regulators of gene expression because they affect a wide range of biological processes, such as cell growth, death, differentiation, and aging. More and more evidence suggests that lncRNAs play a role in maintaining metabolic homeostasis. When certain lncRNAs are out of balance, metabolic disorders like diabetes, obesity, and heart disease get worse. In this review, we talk about what we know about how lncRNAs control metabolism, with a focus on diseases caused by long-term inflammation and the characteristics of the metabolic syndrome. We looked at lncRNAs and their molecular targets in the pathogenesis of signaling pathways. We also talked about how lncRNAs are becoming more and more interesting as diagnostic and therapeutic targets for improving metabolic homeostasis.

Upregulated lncRNA Cyclin-dependent kinase inhibitor 2B antisense RNA 1 induces the proliferation and migration of colorectal cancer by miR-378b/CAPRIN2 axis

LncRNA Cyclin‐dependent kinase inhibitor 2B antisense RNA 1 (CDKN2B-AS1) plays a role in the progression of multiple cancers like cholangiocarcinoma, osteosarcoma and several gastrointestinal tumors. Few studies have linked its function and mechanism to the development of colorectal cancer (CRC). The expression of CDKN2B-AS1, microRNA (miR)-378b, and cytoplasmic activation/proliferation-associated protein 2 (CAPRIN2) was analyzed in CRC patients and cell lines. The proliferation and migration of CRC cells were evaluated after gain and loss-of function mutations. Interactions between CDKN2B-AS1 and miR-378b, miR-378b and CAPRIN2 were validated by luciferase reporter, RNA pull-down and RNA immunoprecipitation assays. The role of CDKN2B-AS1 was further confirmed in a xenograft mouse model. We found that the expression of CDKN2B-AS1 and CAPRIN2 was upregulated in CRC and they were linked to the poor differentiation and distant metastasis in CRC patients. CDKN2B-AS1 knockdown attenuated while CDKN2B-AS1 overexpression promoted CRC cell proliferation and migration. Notably, the results of Starbase 2.0 database analysis and in vitro experiments demonstrated that CDKN2B-AS1 could interact with miR-378b and regulate its expression. Furthermore, CAPRIN2 acted as a downstream target of CDKN2B-AS1/miR-378b that involved in modulating β-catenin expression in CRC cells. Upregulation of CDKN2B-AS1 contributed to CRC progression via regulating CAPRIN2 expression by binding to miR-378b. Downregulation of CDKN2B-AS1 suppressed tumor growth and Ki-67 staining in vivo that was related to the miR-378b/CAPRIN2 pathway. This study indicated that lncRNA CDKN2B-AS1 promoted the development of CRC through the miR-378b/CAPRIN2/β-catenin axis. CDKN2B-AS1 might serve as a potential and useful target in CRC diagnosis and treatment.

LncRNA CDKN2B‑AS1 sponges miR‑28‑5p to regulate proliferation and inhibit apoptosis in colorectal cancer

Long noncoding RNA (lncRNA) CDKN2B‑antisense RNA 1 (AS1) functions as a tumor oncogene in numerous cancers. However, the roles and mechanism of CDKN2B‑AS1 in colorectal cancer (CRC) have not been explored. The present study aimed to investigate whether and how CDKN2B‑AS1 contributes to CRC progression. The data revealed that CDKN2B‑AS1 expression was upregulated in CRC tissues. Loss‑of‑function assays demonstrated that CDKN2B‑AS1 in CRC modulated cell proliferation and apoptosis, which was mediated by cyclin D1, cyclin‑dependent kinase (CDK) 4, p‑Rb, caspase‑9 and caspase‑3. Bioinformatics analysis and luciferase reporter assays indicated direct binding of microRNA (miR)‑28‑5p to CDKN2B‑AS1. Moreover, the results herein revealed that the expression of miR‑28‑5p was negatively correlated with that of CDKN2B‑AS1 in CRC tissue. Moreover, CDKN2B‑AS1 acted as a miR‑28‑5p competing endogenous RNA (ceRNA) to target and regulate the expression of URGCP. These findings indicated that CDKN2B‑AS1 plays roles in CRC progression, providing a potential therapeutic target or novel diagnostic biomarker for CRC.

Long non-coding RNA CDKN2B-AS1 enhances LPS-induced apoptotic and inflammatory damages in human lung epithelial cells via regulating the miR-140-5p/TGFBR2/Smad3 signal network

Background

Sepsis is a complicated disease with systemic inflammation or organ dysfunction, and it is the leading cause of acute lung injury (ALI). Long non-coding RNAs (lncRNAs) have played important roles in the pathogenesis of sepsis. This study was designed to explore the biological function and regulatory mechanism of cyclin-dependent kinase inhibitor 2B antisense RNA 1 (CDKN2B-AS1) in lipopolysaccharide (LPS)-induced lung injury.

Methods

ALI model was established after human lung epithelial cell line BEAS-2B was exposed to LPS. CDKN2B-AS1, microRNA-140-5p (miR-140-5p) and transforming Growth Factor Beta Receptor II (TGFBR2) levels were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Cell viability was measured using Cell Counting Kit-8 (CCK-8). Cell apoptosis was assessed by caspase3 activity and flow cytometry. Inflammatory cytokines were examined via enzyme-linked immunosorbent assay (ELISA). Protein analysis was performed through western blot. Dual-luciferase reporter, RNA immunoprecipitation (RIP) and pull-down assays were applied to validate the interaction between targets.

Results

CDKN2B-AS1 and TGFBR2 were abnormally upregulated in sepsis patients. Functionally, CDKN2B-AS1 or TGFBR2 knockdown promoted cell growth but inhibited cell apoptosis and inflammatory response in LPS-treated BEAS-2B cells. Moreover, the regulation of CDKN2B-AS1 in LPS-induced cell injury was achieved by increasing the TGFBR2 expression. CDKN2B-AS1 was identified as a miR-140-5p sponge and TGFBR2 was a target of miR-140-5p. Furthermore, CDKN2B-AS1 could regulate the TGFBR2/Smad3 pathway by sponging miR-140-5p.

Conclusions

These results suggested that CDKN2B-AS1 contributed to the LPS-mediated apoptosis and inflammation in BEAS-2B cells via the miR-140-5p/TGFBR2/Smad3 axis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-021-01561-z.

Long non-coding RNA exploration for mesenchymal stem cell characterisation

BACKGROUND

The development of RNA sequencing (RNAseq) and the corresponding emergence of public datasets have created new avenues of transcriptional marker search. The long non-coding RNAs (lncRNAs) constitute an emerging class of transcripts with a potential for high tissue specificity and function. Therefore, we tested the biomarker potential of lncRNAs on Mesenchymal Stem Cells (MSCs), a complex type of adult multipotent stem cells of diverse tissue origins, that is frequently used in clinics but which is lacking extensive characterization.

RESULTS

We developed a dedicated bioinformatics pipeline for the purpose of building a cell-specific catalogue of unannotated lncRNAs. The pipeline performs ab initio transcript identification, pseudoalignment and uses new methodologies such as a specific k-mer approach for naive quantification of expression in numerous RNAseq data. We next applied it on MSCs, and our pipeline was able to highlight novel lncRNAs with high cell specificity. Furthermore, with original and efficient approaches for functional prediction, we demonstrated that each candidate represents one specific state of MSCs biology.

CONCLUSIONS

We showed that our approach can be employed to harness lncRNAs as cell markers. More specifically, our results suggest different candidates as potential actors in MSCs biology and propose promising directions for future experimental investigations.

Knockdown of 91 H Suppresses the Tumorigenesis of Osteosarcoma via Inducing Methylation of CDK4 Promoter

Background:

Osteosarcoma is the most leading primary malignancy of the bone in adolescents all over the world. Long non-coding RNA (lncRNA) 91 H has been reported to participated in multiple cancers. Meanwhile, lncRNA 91 H has been proved to be upregulated in osteosarcoma. However, the function of 91 H in osteosarcoma remains unclear.

Methods:

Gene and protein expressions in osteosarcoma cells were detected by qRT-PCR and western blot, respectively. Cell viability was tested by CCK-8 assay. Ki67 staining was used to measure cell proliferation. Cell apoptosis and cycle were assessed by flow cytometry. In addition, transwell assay was used to detect cell migration and invasion. Furthermore, Methylation-specific PCR (MSP) was performed to test the methylation of CDK4 promoter. Finally, xenograft mice model was established to explore the role of 91 H in osteosarcoma in vivo.

Results:

Knockdown of 91 H significantly inhibited the growth of osteosarcoma cells via inducing the cell apoptosis. In addition, 91 H siRNA notably suppressed the migration and invasion of osteosarcoma cells. Meanwhile, knockdown of 91 H inhibited the progression of osteosarcoma via inducing methylation of CDK4 promoter. Furthermore, 91 H knockdown obviously induced G1 arrest in osteosarcoma cells via inhibition of PCNA and Cyclin D1. Finally, knockdown of 91 H notably inhibited the tumor growth of osteosarcoma in vivo.

Conclusion:

knockdown of 91 H suppressed the tumorigenesis of osteosarcoma via inducing methylation of CDK4 promoter in vitro and in vivo. Thus, 91 H may serve as a new target for the treatment of osteosarcoma.

Long non-coding RNA CDKN2B-AS1 regulates high glucose-induced human mesangial cell injury via regulating the miR-15b-5p/WNT2B axis

BACKGROUND

Long non-coding RNA cyclin-dependent kinase inhibitor 2B antisense RNA 1 (CDKN2B-AS1) has been reported to be related to diabetic nephropathy (DN) progression. However, the regulatory mechanisms of CDKN2B-AS1 in DN are unclear.

METHODS

High glucose (HG) was used to induce human mesangial cells (HMCs) for establishing the DN model. Expression levels of CDKN2B-AS1, microRNA (miR)-15b-5p, wingless-Type family member 2B (WNT2B) mRNA in serum and HMCs were detected through quantitative real-time polymerase chain reaction (qRT-PCR). The viability and cell cycle progression of HMCs were determined with Cell Counting Kit-8 (CCK-8) or flow cytometry assays. The levels of several proteins and inflammatory factors in HMCs were analyzed by western blotting or enzyme-linked immunosorbent assay (ELISA). The relationship between CDKN2B-AS1 or WNT2B and miR-15b-5p was verified with dual-luciferase reporter assay.

RESULTS

CDKN2B-AS1 and WNT2B were upregulated while miR-15b-5p was downregulated in serum of DN patients and HG-treated HMCs. CDKN2B-AS1 inhibition reduced HG-induced viability, cell cycle progression, ECM accumulation, and inflammation response in HMCs. CDKN2B-AS1 regulated WNT2B expression via competitively binding to miR-15b-5p. MiR-15b-5p inhibitor reversed CDKN2B-AS1 knockdown-mediated influence on viability, cell cycle progression, ECM accumulation, and inflammation response of HG-treated HMCs. The repressive effect of miR-15b-5p mimic on viability, cell cycle progression, ECM accumulation, and inflammation response of HG-treated HMCs was abolished by WNT2B overexpression.

CONCLUSION

CDKN2B-AS1 regulated HG-induced HMC viability, cell cycle progression, ECM accumulation, and inflammation response via regulating the miR-15b-5p/WNT2B axis, provided a new mechanism for understanding the development of DN.

Long Noncoding RNA CDKN2B-AS1 Facilitates Lung Cancer Development Through Regulating miR-378b/NR2C2

Aim

Long noncoding RNA (lncRNA) have proved to be important regulators in various diseases. CDKN2B-AS1 was a newly identified tumor-related lncRNA, and previous studies have reported its function in laryngeal squamous cancer and osteosarcoma. However, the function and mechanism of lncRNA CDKN2B-AS1 in lung cancer are still unknown.

Methods

Cell proliferation, invasion, migration and apoptosis were detected via CCK-8, transwell assay and Western blot. Bioinformatics analysis was used to predict the potential target of CDKN2B-AS1. A rescue experiment was performed to identify the relationship between CDKN2B-AS1 and miR-378b.

Results

The expression of lncRNA CDKN2B-AS1 was significantly upregulated in lung cancer tissues and cell lines. Overexpression of CDKN2B-AS1 promoted cell proliferation, invasion and reduced cell apoptosis. Knockdown of CDKN2B-AS1 inhibited cell proliferation, invasion and increased cell apoptosis. Bioinformatics analysis predicted that miR-378b was the direct target. We also provided evidence that NR2C2 was the target of miR-378b. The expression of NR2C2 was significantly upregulated in lung cancer tissues and cell lines. The rescue experiment further confirmed the relationship between CDKN2B-AS1 and miR-378b. Overexpression of miR-378b completely reversed the function of CDKN2B-AS1.

Conclusion

Taken together, our results comprehensively analyzed the function of CDKN2B-AS1 in lung cancer and provided a possible mechanism that CDKN2B-AS1 facilitates lung cancer development by regulating miR-378b and NR2C2. Thus, our study offers a potential therapeutic target for treating lung cancer.