Stathmin1 overexpression in hypopharyngeal squamous cell carcinoma: A new promoter in FaDu cell proliferation and migration

Network pharmacology prediction and molecular docking-based strategy to explore the potential mechanism of Radix Astragali against hypopharyngeal carcinoma

To explore the anti-tumor effects of Radix Astragali on hypopharyngeal carcinoma and its mechanism. We have bioinformatically analyzed the potential targets of Radix Astragali and predicted the molecular mechanism of Radix Astragali treating of hypopharyngeal carcinoma. The binding process of the hub targets that could prolong the survival time of hypopharyngeal cancer patients with Radix Astragali was simulated by molecular docking. The results showed that 17 out of 36 hub targets could effectively improve the 5-year survival rate of hypopharyngeal cancer patients. Radix Astragali acts on hypopharyngeal carcinoma by regulating a signaling network formed by hub targets connecting multiple signaling pathways and is expected to become a drug for treating and prolonging hypopharyngeal carcinoma patients' survival time.

STNM1 in human cancers: role, function and potential therapy sensitizer

STMN1 belongs to the stathmin gene family, it encodes a cytoplasmic phosphorylated protein, stathmin1, which is commonly observed in vertebrate cells. STMN1 is a structural microtubule-associated protein (MAP) that binds to microtubule protein dimers rather than microtubules, with each STMN1 binding two microtubule protein dimers and preventing their aggregation, leading to microtubule instability. STMN1 expression is elevated in a number of malignancies, and inhibition of its expression can interfere with tumor cell division. Its expression can change the division of tumor cells, thereby arresting cell growth in the G2/M phase. Moreover, STMN1 expression affects tumor cell sensitivity to anti-microtubule drug analogs, including vincristine and paclitaxel. The research on MAPs is limited, and new insights on the mechanism of STMN1 in different cancers are emerging. The effective application of STMN1 in cancer prognosis and treatment requires further understanding of this protein. Here, we summarize the general characteristics of STMN1 and outline how STMN1 plays a role in cancer development, targeting multiple signaling networks and acting as a downstream target for multiple microRNAs, circRNAs, and lincRNAs. We also summarize recent findings on the function role of STMN1 in tumor resistance and as a therapeutic target for cancer.

Stathmin1 promotes lymph node metastasis in hypopharyngeal squamous cell carcinoma via regulation of HIF‑1α/VEGF‑A axis and MTA1 expression

Extensive neck lymph node metastasis (LNM) is an important clinical feature of hypopharyngeal squamous cell carcinoma (HSCC). Stathmin1 (STMN1) is closely associated with LNM in numerous human cancers. In the present study, the association between STMN1 and neck LNM in HSCC and the underlying molecular mechanisms were explored. First, postoperative samples of HSCC were screened and the association between STMN1 and neck LNM in HSCC was analyzed. Then, cell functional experiments were performed to assess the potential of STMN1 to promote invasion and migration. Subsequently, the potential target genes and pathways of STMN1 were predicted using bioinformatics analysis. Finally, the obtained target genes and pathways of STMN1 were validated by reverse transcription-quantitative PCR (RT-qPCR) and western blot analyses to confirm the potential mechanisms by which STMN1 promotes LNM in HSCC. As a result, a total of 117 postoperative samples of HSCC were screened, and STMN1 was proven to be associated with neck LNM in HSCC. Further, cell functional experiments established that high expression of STMN1 could actually promote FaDu cell invasion and metastasis. Bioinformatics analysis revealed that high expression of STMN1 was associated with the activation of hypoxia inducible factor-1alpha (HIF-1α) pathway and increased expression of metastasis-associated protein 1 (MTA1). Finally, RT-qPCR and western blot analyses confirmed that STMN1 promotes the expression levels of HIF-1α/vascular endothelial growth factor (VEGF)-A and MTA1 in FaDu cell lines. In conclusion, it was found that high expression of STMN1 promoted neck LNM in HSCC and the potential mechanisms may be via regulation of the HIF-1α/VEGF-A axis and MTA1 expression.

Overexpression of Stathmin 1 Predicts Poor Prognosis and Promotes Cancer Cell Proliferation and Migration in Ovarian Cancer

Purpose

The aim of this study was to investigate the expression of stathmin 1 (STMN1) in ovarian cancer and its effect on prognosis. The effect and mechanism of STMN1 on the proliferation and migration of ovarian cancer cells were also investigated.

Methods

Expression of STMN1 was measured by immunohistochemical staining in ovarian cancer tissues. The effects of STMN1 on the proliferation and migration capacity of ovarian cancer were evaluated using Cell Counting Kit-8 (CCK-8) assays, colony formation assays, immunofluorescence staining, wound healing assays, and Transwell assays. Transcription factors were predicted by bioinformatic analysis of TCGA database.

Results

STMN1 was upregulated in ovarian cancer tissues as compared to paracancerous tissues and associated with shorter overall survival. STMN1 expression significantly correlated with FIGO staging and tumor differentiation (P < 0.05). Furthermore, STMN1 promoted proliferation and migration in ovarian cancer cell lines. Bioinformatic analysis revealed that STMN1 was potentially regulated by E2F transcription factors. Then, we found that E2F1 regulated the expression of STMN1 and affected proliferation.

Conclusion

STMN1 is overexpressed in ovarian cancer, and its high expression suggests a poor prognosis. STMN1 promotes the proliferation and migration of ovarian cancer and is regulated by E2F1. Thus, STMN1 may serve as a negative prognostic factor and possible target for the treatment of ovarian cancer patients.

DNA methyltransferase 1 inhibits O6-methylguanine-DNAmethyl-transferase-mediated cell growth and metastasis of hypopharyngeal squamous carcinoma

OBJECTIVE

To explore the role of DNA methyltransferase 1 (DNMT1) in development and progression of hypopharyngeal squamous carcinoma.

DESIGN

A total of 32 hypopharyngeal squamous carcinoma biopsy samples and 20 normal tissue specimens were collected. Immunohistochemical staining, quantitative real-time polymerase chain reaction, and Western blot were performed for expression analysis. The mRNA and protein expression in the specimens and subcellular localization were analyzed. hypopharyngeal squamous carcinoma cells (FaDu) were used for small interfering RNA of DNMT1, and proliferation, cell cycle, and apoptosis were determined in the transfected cells. Furthermore, metastatic ability and methylation status of O⁶-methylguanine-DNAmethyl-transferase (MGMT) promoter was assessed.

RESULTS

Our results showed that DNMT1 was overexpressed, while MGMT was down expressed in hypopharyngeal squamous carcinoma. DNMT1 overexpression and MGMT down expression were significantly associated with poorly differentiated tumors, lymph node metastasis, and clinical stage. DNMT1 and MGMT were majorly distributed in the nucleus. Furthermore, knockdown of DNMT1 inhibited proliferation and metastasis, induced apoptosis and G1 phase arrest in FaDu cells, and upregulated MGMT expression to reverse methylation status of MGMT promoter.

CONCLUSIONS

This study for the first time demonstrated the clinical value and the role of DNMT1 and MGMT in the biological function of hypopharyngeal squamous carcinoma. This work suggested that DNMT1 might serve as a potential therapeutic target for patients with hypopharyngeal squamous carcinoma.

CircRNA ZNF609 promotes angiogenesis in nasopharyngeal carcinoma by regulating miR-145/STMN1 axis

Nasopharyngeal carcinoma (NPC) is the most common type of human malignant tumor in the head and neck, and tumor angiogenesis is essential for its development. Here, we showed that the circRNA ZNF609/microRNA (miR)-145/Stathmin 1 (STMN1) axis regulated angiogenesis in NPC.Circ-ZNF609, miR-145, and STMN1 expression in NPC cells and NPC samples were examined using qRT-PCR. The protein levels of STMN1, VEGFR1, and VEGFR2 were evaluated using western blotting. VEGF level was determined by ELISA. The proliferation of NPC cells and HUVECs was examined using a CCK-8 assay. Transwell assays and wound-healing assays were applied to assess the migration of NPC cells and HUVECs, respectively. Angiogenesis of HUVECs was evaluated by an angiogenesis assay. In addition, a dual-luciferase reporter assay and RNA pull-down assays were employed to verify the binding relationship between circ-ZNF609 and miR-145 as well as between miR-145 and STMN1. Here, we showed that circ-ZNF609 and STMN1 expression was increased, while miR-145 expression was decreased in NPC cells and NPC samples. Circ-ZNF609 may negatively regulate miR-145 expression by acting as a ceRNA. Silencing circ-ZNF609 suppressed cell proliferation, migration, and angiogenesis in NPC, while knockdown of miR-145 reversed these effects. In addition, we found that STMN1 was the downstream target of miR-145. MiR-145 overexpression suppressed cell proliferation, migration, and angiogenesis in NPC, which was abolished by STMN1 overexpression. Our data suggested that circ-ZNF609 promotes cell proliferation, migration, and angiogenesis in NPC by upregulating the expression of STMN1 by sponging miR-145 in NPC.

circST6GALNAC6 suppresses bladder cancer metastasis by sponging miR-200a-3p to modulate the STMN1/EMT axis

Bladder cancer (BCa) is an aggressive malignancy because of its distant metastasis and high recurrence rate. Circular RNAs (circRNAs) exert critical regulatory functions in cancer progression. However, the expression patterns and roles of circRNAs in BCa have not been well investigated. In this study, we first screened circRNA expression profiles using a circRNA microarray of paired BCa and normal tissues, and the expression of circST6GALNAC6 was confirmed by qRT-PCR and fluorescence in situ hybridization (FISH). MTT, colony formation and Transwell assays were performed to measure cell proliferation, migration and invasion. We investigated the regulatory effect of circST6GALNAC6 on miRNA and its target genes to explore the potential regulatory mechanisms of circST6GALNAC6 by chromatin immunoprecipitation (ChIP), RNA immunoprecipitation (RIP), MS2-tagged RNA affinity purification (MS2-TRAP), immunofluorescence (IF) and dual luciferase activity assays. A nude mouse xenograft model was used to examine the functions of circST6GALNAC6/STMN1 in tumour metastasis in vivo. We found that 881 circRNAs were significantly dysregulated in BCa tissues compared to normal tissues. circST6GALNAC6(hsa_circ_0088708) was downregulated in BCa tissues and cells. Overexpression of circST6GALNAC6 effectively inhibited the cell proliferation, migration, invasion and epithelial-mesenchymal transition (EMT) in vitro and suppressed BCa metastasis in vivo. Mechanistically, we showed that the SP1 transcription factor, which binds to the circST6GALNAC6 mRNA transcript, activates circST6GALNAC6 transcription. Next, we verified that circST6GALNAC6 serves as a sponge that directly binds miR-200a-3p to regulate stathmin (STMN1) expression. Furthermore, we found that STMN1 is involved in circST6GALNAC6/miR-200a-3p axis-regulated BCa EMT and metastasis. Thus, our findings indicate an important underlying mechanism in BCa metastasis by which SP1-induced circST6GALNAC6 sponges miR-200a-3p to promote STMN1/EMT signalling. This mechanism could provide pivotal potential prognostic biomarkers and therapeutic targets for BCa.

Zyxin (ZYX) promotes invasion and acts as a biomarker for aggressive phenotypes of human glioblastoma multiforme

Glioblastoma multiforme (GBM) is characterized by highly invasive growth, which leads to extensive infiltration and makes complete tumor excision difficult. Since cytoskeleton proteins are related to leading processes and cell motility, and through analysis of public GBM databases, we determined that an actin-interacting protein, zyxin (ZYX), may involved in GBM invasion. Our own glioma cohort as well as the cancer genome atlas (TCGA), Rembrandt, and Gravendeel databases consistently showed that increased ZYX expression was related to tumor progression and poor prognosis of glioma patients. In vitro and in vivo experiments further confirmed the oncogenic roles of ZYX and demonstrated the role of ZYX in GBM invasive growth. Moreover, RNA-seq and mass-spectrum data from GBM cells with or without ZYX revealed that stathmin 1 (STMN1) was a potential target of ZYX. Subsequently, we found that both mRNA and protein levels of STMN1 were positively regulated by ZYX. Functionally, STMN1 not only promoted invasion of GBM cells but also rescued the invasion repression caused by ZYX loss. Taken together, our results indicate that high ZYX expression was associated with worse prognosis and highlighted that the ZYX-STMN1 axis might be a potential therapeutic target for GBM.

Identification of potential biomarkers in cervical cancer with combined public mRNA and miRNA expression microarray data analysis

Cervical cancer is the fourth most prevalent malignancy in females worldwide. Early diagnosis is key to improving survival rates. Molecular biomarkers are an important method for diagnosing a number of types of cancer, including cervical cancer. The present study utilized public data from three mRNA microarray datasets and one microRNA dataset to analyze the key genes involved in cervical cancer. The mRNA and microRNA expression profile datasets (GSE9750, GSE46857, GSE67522 and GSE30656) were downloaded from the Gene Expression Omnibus database (GEO). Differentially expressed genes (DEGs) and microRNAs (DEMs) were screened using the online tool GEO2R. By using the DEGs consistent across the three mRNA datasets, a functional and pathway enrichment analysis was performed using the Database for Annotation, Visualization and Integrated Discovery. A protein-protein interaction (PPI) network was constructed and module analysis performed using the Search Tool for the Retrieval of Interacting Genes. Validated target genes of the DEMs were identified using the miRecords website. Using the identified target genes of the DEMs, a survival analysis was performed using the OncoLnc online tool. A total of 73 DEGs and 19 DEMs were screened from the microarray expression profile datasets. ‘Integrin-mediated’, ‘proteolysis’ and ‘phosphoinositide 3 kinase-protein kinase 3’ signaling pathways were the most enriched in the DEGs. Three of the DEGs, including Ras homolog family member B (RhoB), stathmin 1 (STMN1) and cyclin D1 (CCNB1) were validated DEM target genes. The OncoLnc survival analysis identified that RhoB was associated with a significantly longer overall survival, whereas STMN1 was associated with a significantly reduced overall survival time in patients with cervical cancer. Finally, data from The Cancer Genome Atlas revealed an association between the mRNA expression levels of RhoB and STMN1, and the overall survival time for patients with cervical cancer. In conclusion, RhoB and STMN1 were identified as key genes that may provide potential targets for cervical cancer diagnosis and treatment.