NOB1 silencing inhibits the growth and metastasis of laryngeal cancer cells through the regulation of JNK signaling pathway

The proximity proteome of pre-40S pre-ribosomal particle components PNO1 and NOB1 using turboID proximity labeling technology

BACKGROUND

The ribosome assembly factors PNO1 and NOB1 play crucial roles in the maturation of the 40S ribosomal small subunit. TurboID is an efficient biotin ligase that can biotinylate proteins in proximity to the target protein and is widely used to study complex biological processes within cells. In this study, we employed this technology to investigate the complex proximity network of PNO1 and NOB1 within the cell, further revealing their key roles in ribosome biogenesis.

RESULTS

Firstly, through immunofluorescence experiments, we observed that PNO1 and NOB1 have different localizations within the cell. Subsequently, by analyzing the proximal proteins labeled by PNO1-TurboID and NOB1-TurboID, we identified 871 proximal proteins for PNO1 and 1044 for NOB1, with 663 overlapping proteins. Functional analysis revealed that these proximal proteins are predominantly enriched in biological processes related to ribosome assembly, rRNA processing, and translation, all of which are closely linked to ribosome biogenesis. Notably, we validated the mass spectrometry-identified proteins through co-IP experiments and found that PNO1 and NOB1 interact with the translation-related proteins EIF4B and EIF4G2.

CONCLUSION

Our study constructed the protein network environment of ribosome assembly factors PNO1 and NOB1 within the cell and found that their neighboring proteins are primarily involved in key biological processes such as ribosome processing, mRNA translation, and the cell cycle, all of which are critical for ribosome biogenesis. These findings provide a valuable foundation for further understanding the roles of PNO1 and NOB1 in ribosome biogenesis and how they regulate this process.

Signal Pathways and microRNAs in Osteosarcoma Growth and the Dual Role of Mesenchymal Stem Cells in Oncogenesis

The major challenges in Osteosarcoma (OS) therapy are its heterogeneity and drug resistance. The development of new therapeutic approaches to overcome the major growth mechanisms of OS is urgently needed. The search for specific molecular targets and promising innovative approaches in OS therapy, including drug delivery methods, is an urgent problem. Modern regenerative medicine focuses on harnessing the potential of mesenchymal stem cells (MSCs) because they have low immunogenicity. MSCs are important cells that have received considerable attention in cancer research. Currently, new cell-based methods for using MSCs in medicine are being actively investigated and tested, especially as carriers for chemotherapeutics, nanoparticles, and photosensitizers. However, despite the inexhaustible regenerative potential and known anticancer properties of MSCs, they may trigger the development and progression of bone tumors. A better understanding of the complex cellular and molecular mechanisms of OS pathogenesis is essential to identify novel molecular effectors involved in oncogenesis. The current review focuses on signaling pathways and miRNAs involved in the development of OS and describes the role of MSCs in oncogenesis and their potential for antitumor cell-based therapy.

Overexpression of microRNA-107 suppressed proliferation, migration, invasion, and the PI3K/Akt signaling pathway and induced apoptosis by targeting Nin one binding (NOB1) protein in a hypopharyngeal squamous cell carcinoma cell line (FaDu)

Hypopharyngeal squamous cell carcinoma (HSCC) is one of the most common head and neck cancers, with a worst prognosis owing to its aggressivity. MicroRNA-107 (miR-107) is reported to regulate the progression of various cancers. Nevertheless, its implied function in HSCC remains unclear. This study is aimed to exploring the roles and potential mechanisms of miR-107 in HSCC. We found that miR-107 expression was significantly decreased in HSCC tissues compared with the para-cancer tissues. Moreover, miR-107 overexpression by miR-107 mimics decreased FaDu cell viability, led to cell cycle arrest in G1/S phase, accelerated apoptosis, and reduced cell migration and invasion. MiR-107 possibly resulted in deactivation of the phosphatidylinositol 3-kinase (PI3K)/Akt pathway, evidenced by the decrease of phosphorylated (p-) PI3K and p-Akt. Besides, dual-luciferase reporter assay confirmed that miR-107 might bind to the 3’UTR of Nin one binding protein 1 (NOB1), and elevated NOB1 expression in HSCC tissues and a negative correlation between miR-107 and NOB1 were found. Rescue assays demonstrated the significant roles of miR-107 in FaDu cell behavior by modulating NOB1. In addition, the tumorigenic potential of miR-107 in vivo was conducted. It was found that miR-107 overexpression in FaDu cells significantly inhibited tumor growth and led to inactivation of the PI3K/Akt signaling. The above findings revealed that miR-107 could suppress FaDu cell proliferation, migration, invasion and induced apoptosis by targeting NOB1 through the PI3K/Akt pathway, suggesting that miR-107/NOB1 axis may exert a key role in FaDu HSCC development.

LncRNA FEZF1-AS1 aggravates cell proliferation and migration in glioblastoma

OBJECTIVES

Glioblastoma (GBM) represents the commonest malignant glioma. Long non-coding RNA (lncRNA) FEZ family zinc finger 1 antisense RNA 1 (FEZF1-AS1) has been validated to play an oncogenic role in multiple human malignancies, while its function in GBM has not been largely reported. We aim to identify the regulatory mechanism of FEZF1-AS1 in GBM.

MATERIALS & METHODS

The expression pattern of FEZF1-AS1 was firstly figured out in GBM cells using RT-qPCR. Then, functional assays were conducted to examine the influence FEZF1-AS1 had on the biological properties of GBM cells. The downstream targets of FEZF1-AS1 were predicted and the underlying regulatory mechanism was determined by mechanism assays.

RESULTS

FEZF1-AS1 possessed high expression in GBM cells. Down-regulation of FEZF1-AS1 suppressed GBM cell proliferation, migration and invasion while inducing cell apoptosis. With the help of bioinformatics prediction and mechanism assays, FEZF1-AS1 was found to bind to miR-363-3p and NOB1 was determined to be the downstream gene. Finally, results of rescue assays verified that the suppressive function of FEZF1-AS1 inhibition on GBM development were restored by miR-363-3p depletion or overexpression of NOB1.

CONCLUSION

FEZF1-AS1 had oncogenic function in the advancement of GBM by targeting miR-363-3p/NOB1, which made FEZF1-AS1 a potential biomarker for GBM treatment.

Unraveling the roles of miRNAs in regulating epithelial-to-mesenchymal transition (EMT) in osteosarcoma

Osteosarcoma is one of the most prevalent primary bone tumors with a high metastatic and recurrence rate with poor prognosis. MiRNAs are short and non-coding RNAs that could regulate various cellular activities and one of them is the epithelial-to-mesenchymal transition (EMT). Osteosarcoma cells that have undergone EMT would lose their cellular polarity and acquire invasive and metastatic characteristics. Our literature search showed that many pre-clinical and clinical studies have reported the roles of miRNAs in modulating the EMT process in osteosarcoma and compared to other cancers like breast cancer, there is a lack of review article which effectively summarizes the various roles of EMT-regulating miRNAs in osteosarcoma. This review, therefore, was aimed to discuss and summarize the EMT-promoting and EMT-suppressing roles of different miRNAs in osteosarcoma. The review would begin with the discussion on the concepts and principles of EMT, followed by the exploration of the diverse roles of EMT-regulating miRNAs in osteosarcoma. Subsequently, the potential use of miRNAs as prognostic biomarkers in osteosarcoma to predict the likelihood of metastases and as therapeutic agents would be discussed.

NOB1: A Potential Biomarker or Target in Cancer

Human NIN1/RPN12 binding protein 1 homolog (NOB1), an RNA binding protein, is expressed ubiquitously in normal tissues such as the lung, liver, and spleen. Its core physiological function is to regulate protease activities and participate in maintaining RNA metabolism and stability. NOB1 is overexpressed in a variety of cancers, including pancreatic cancer, non-small cell lung cancer, ovarian cancer, prostate carcinoma, osteosarcoma, papillary thyroid carcinoma, colorectal cancer, and glioma. Although existing data indicate that NOB1 overexpression is associated with cancer growth, invasion, and poor prognosis, the molecular mechanisms behind these effects and its exact roles remain unclear. Several studies have confirmed that NOB1 is clinically relevant in different cancers, and further research at the molecular level will help evaluate the role of NOB1 in tumors. NOB1 has become an attractive target in anticancer therapy because it is overexpressed in many cancers and mediates different stages of tumor development. Elucidating the role of NOB1 in different signaling pathways as a potential cancer treatment will provide new ideas for existing cancer treatment methods. This review summarizes the research progress made into NOB1 in cancer in the past decade; this information provides valuable clues and theoretical guidance for future anticancer therapy by targeting NOB1.

MiR-363 suppresses cell migration, invasion, and epithelial-mesenchymal transition of osteosarcoma by binding to NOB1

Background

Osteosarcoma (OS) is a primary malignant bone tumor with a high rate of metastasis and a short 5-year survival rate. MiR-363 was downregulated in a variety of tumors and played a role in suppressing tumors. However, the roles of miR-363 in osteosarcoma remain unknown; thus, the purpose of this study was to explore the functions of miR-363 in osteosarcoma.

Methods

CCK-8 and transwell assays were performed to evaluate the proliferation, migration, and invasion abilities of MG63 cells. The epithelial-mesenchymal transition (EMT) and apoptosis-associated proteins were measured by using Western blot assay. Luciferase reporter assay was utilized to verify whether miR-363 directly bound to the 3′-UTR of NOB1 mRNA.

Results

MiR-363 was downregulated while NOB1 was upregulated in osteosarcoma clinical tissue specimens and cell lines as compared with the adjacent normal tissue specimens and normal cell line. The miR-363 is reversely correlated with the expression of NOB1 in osteosarcoma tissues. Overexpression of miR-363 suppressed the ability of cell migration, invasion, and EMT, whereas low expression of miR-363 promoted this ability. In addition, miR-363 inhibited osteosarcoma proliferation both in vitro and in vivo and inhibited the apoptosis in MG63 cells. Interference of NOB1 could inhibit the migration, invasion, and EMT of osteosarcoma cell line MG63. NOB1 was verified to be a direct target of miR-363 and its expression was mediated by miR-363. Re-expression of NOB1 could partially reverse the inhibitory effect of miR-363 on cell migration and invasion. In addition, low expression of miR-363 or overexpression of NOB1 predicted poor prognosis of osteosarcoma patients.

Conclusion

MiR-363 inhibited osteosarcoma the proliferation, migration, invasion, and EMT and induced the apoptosis by directly targeting NOB1 in MG63 cells. The newly identified miR-363/NOB1 axis provides novel insights into the pathogenesis of osteosarcoma.

microRNA-195 attenuates neuronal apoptosis in rats with ischemic stroke through inhibiting KLF5-mediated activation of the JNK signaling pathway

BACKGROUND

Accumulating evidence has implicated the regulation of microRNAs (miRs) in ischemia stroke. The current study aimed to elucidate the role of microRNA-195 (miR-195) in neuronal apoptosis and brain plasticity in rats with ischemic stroke via the JNK signaling pathway/KLF5 axis.

METHODS

Ischemic stroke rat models were established by middle cerebral artery occlusion (MCAO), and oxygen deprivation (OGD) models were constructed in rat neuronal cells, followed by gain- or loss-of-function of miR-195 and/or KLF5 in rats and cells. Infarct volume, neuronal loss and ultrastructure, the expression of GAP-43, SYP and KLF5 protein as well as cell apoptosis were determined in the rats. Caspase-3 activity as well as the expression of miR-195, KLF5, GAP-43, SYP, JNK, phosphorylated JNK, Bax and Bcl-2 was measured in the cells.

RESULTS

The infarct size, expression of GAP-43 and SYP protein and apoptotic cells were increased in the miR-195^-/- MCAO rats, while reductions were detected in the miR-195 mimic MCAO and KLF5^-/- MCAO rats. Bcl-2 expression was increased, Bax and Caspase-3 expression as well as the ratio of phosphorylated JNK/JNK was decreased in response to miR-195 overexpression or KLF5 knockdown. Interestingly, the silencing of KLF5 reversed the effects exerted by the miR-195 inhibitor on the expression of Bcl-2, phosphorylated JNK/JNK, Bax and Caspase-3.

CONCLUSIONS

Collectively, our study unraveled that miR-195 could down-regulate KLF5 and block the JNK signaling pathway, ultimately inhibiting neuronal apoptosis in rats with ischemic stroke.

Silencing NOB1 Can Affect Cell Proliferation and Apoptosis Via the C-Jun N-Terminal Kinase Pathway in Colorectal Cancer

OBJECTIVES

To investigate the bio-functions and the molecular mechanisms of NIN1/proteasome 26S subunit non-ATPase 8 binding protein 1 homolog (NOB1) in colorectal cancer cells.

METHODS

NOB1 expression was silenced using si-RNA in SW480 and LoVo cells. The transfection efficiency was measured by western blotting and RT-qPCR. Subsequently, the proliferation of SW480 and LoVo cells was determined using both MTT assay and colony-formation assay. Apoptosis and cell cycle analysis were determined using flow cytometry.

RESULTS

Compared with the normal control (NC) and scramble cells, si-NOB1 could significantly attenuate the proliferation, colony-formation ability and cell percentage of S stage (p < 0.05). Additionally, at the phosphorylation level, si-NOB1 could notably increase the expression of c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK) and p38.

CONCLUSIONS

Inhibition of NOB1 expression suppressed the proliferation, and promoted the apoptosis through regulation of the JNK signaling pathway.

[Eukaryotic translation elongation factor 1A1 positively regulates NOB1 expression to promote invasion and metastasis of hepatocellular carcinoma cells in vitro]

OBJECTIVE

To explore the role of eukaryotic translation elongation factor 1A1 (eEF1A1) in regulating the invasion and metastasis of hepatocellular carcinoma (HCC) cells and the possible mechanism.

METHODS

qRT-PCR and Western blotting were used to detect the mRNA and protein expression of eEF1A1 and NOB1 in different HCC cell lines and normal liver cells. The invasion and migration abilities of HCC cells with eEF1A1 knockdown or overexpression were examined using Transwell chamber assay and RTCA assay, and the changes in NOB1 mRNA and protein expressions in the cells were detected. The effects of increasing NOB1 expression in HCCLM3-sheEF1A1 cells and decreasing NOB1 expression in eEF1A1-overexpressing MHCC97h cells on eEF1A1 expression and cell invasion and migration abilities were analyzed using Western blotting, Transwell chamber assay and RTCA assay.

RESULTS

The expressions of eEF1A1 and NOB1 were significantly increased in positive correlation in HCC cells as compared with normal hepatocytes. Knockdown of eEF1A1 significantly decreased the invasion and migration of HCC cells and reduced the mRNA and protein expression of NOB1 (P &lt; 0.01). Overexpression of eEF1A1 significantly enhanced invasion and migration of HCC cells and increased NOB1 mRNA and protein expressions (P &lt; 0.01). Increasing NOB1 expression in HCCLM3-sheEF1A1 cells led to the restoration of NOB1 expression and cell invasion and migration abilities (P &lt; 0.01), whereas decreasing NOB1 in MHCC97h-eEF1A1 cells resulted in inhibition of NOB1 expression and cell invasion and migration (P &lt; 0.01).

CONCLUSIONS

eEF1A1 positively regulates the expression of NOB1 to promote the invasion and migration of HCC cells in vitro.

Effects of NOB1 on the pathogenesis of osteosarcoma and its expression on the chemosensitivity to cisplatin

The effects of NIN1/RPN12 binding protein 1 homolog (NOB1) on the pathogenesis of osteosarcoma and its expression on the chemosensitivity to cisplatin were investigated. Seventy-four patients with osteosarcoma who received surgical resection in The Affiliated Hospital of Southwest Medical University (Sichuan, China) from September 2013 to September 2016 were enrolled in this study. The expression of NOB1 in cancer and cancer-adjacent tissues of patients was detected by reverse transcription-polymerase chain reaction, and the relationship between NOB1 expression and the pathogenesis of osteosarcoma was analyzed. The expression of NOB1 in osteosarcoma MG-63 cells was interfered with using small interfering ribonucleic acid (siRNA). Western blotting was used to detect the transfection efficiency and changes in apoptosis indicators. Cell Counting Kit-8 (CCK-8) assay was used to examine changes in the sensitivity of cells to cisplatin. The effect of NOB1 knockout on cell apoptosis was examined by flow cytometry. In patients with osteosarcoma, the level of NOB1 mRNA in cancer tissues was significantly higher than that in cancer-adjacent tissues (p<0.05), and the expression of NOB1 was correlated with Ennecking staging and tumor size (p<0.05). The expression level of the apoptotic indicator caspase-3 was activated after siRNA interfered with NOB1 expression, thus reducing the expression level of anti-apoptotic indicator B-cell lymphoma 2. CCK-8 results showed that the downregulation of NOB1 increased the sensitivity of MG-63 cells to cisplatin (p<0.05). In addition, flow cytometry showed that the downregulation of NOB1 significantly promoted the apoptosis of MG-63 cells. NOB1 is significantly upregulated in patients with osteosarcoma, thus reducing the curative effect of cisplatin chemotherapy, which indicates that the prognosis is poor.

MicroRNA-363 inhibits ovarian cancer progression by inhibiting NOB1

In this study, we investigated the role of microRNA-363(miR-363) in ovarian cancer (OC) progression. MiR-363expression was downregulated in OC patient tissues and four OC cell lines (SKOV3, A2780, OVCAR and HO-8910). Low miR-363 levels were associated with advanced stage, lymph node metastasis, and poor prognosis in OC. MiR-363 overexpression decreased growth, colony formation, migration and invasiveness of SKOV3 cells. In addition, miR-363 overexpression in SKOV3 cells also decreased xenograft tumor size and weight in nude mice. Bioinformatics and dual luciferase reporter assays revealed that miR-363 suppresses expression of NIN1/RPN12 binding protein 1 homolog (NOB1) by binding to the 3’-UTR of its transcript. NOB1 expression inversely correlated with miR-363 levels in OC tissues. Thus miR-363 appears to play a tumor suppressor role in OC by inhibiting NOB1.

Inhibition of NOB1 by microRNA-330-5p overexpression represses cell growth of non-small cell lung cancer

MicroRNAs (miRNAs) play critical roles in the development and progression of various cancers, including non-small-cell lung cancer (NSCLC). Studies have suggested that miR-330-5p is involved in the progression of several cancers. However, the role of miR-330-5p in NSCLC remains unclear. We investigated the effect on and mechanism of miR-330-5p in the progression of NSCLC. We found that miR-330-5p was significantly downregulated in NSCLC tissues and cell lines as detected by real-time quantitative polymerase chain reaction (RT-qPCR). The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), bromodeoxyuridine (BrdU), colony formation and cell cycle assays showed that overexpression of miR-330-5p markedly inhibited cell growth. Annexin V-FITC/PI and caspase-3 activity assays showed that overexpression of miR-330-5p significantly promoted cell apoptosis of NSCLC cells. Bioinformatics analysis and dual-luciferase reporter assays confirmed NIN/RPN12 binding protein 1 (NOB1) as a target gene of miR-330-5p. RT-qPCR and Western blot analysis showed that overexpression of miR-330-5p inhibited the expression of NOB1 as well as cyclin D1 and cyclin-dependent kinase 4 in NSCLC cells. Moreover, overexpression of NOB1 markedly reversed the miR‑330-5p-mediated inhibitory effect on NSCLC cell growth. Correlation analysis showed that miR‑330-5p expression was inversely correlated with NOB1 mRNA expression in NSCLC tissues. Taken together, our results indicate that miR-330-5p inhibits NSCLC cell growth through downregulation of NOB1 expression. Our study suggests that miR-330-5p may serve as a potential therapeutic target for the treatment of NSCLC.