Involvement of nuclear protein C23 in activation of EGFR signaling in cervical cancer

Integrated In-Silico and In Vitro analysis to Decipher the contribution of bisphenol-A in cervical cancer

Bisphenol A (BPA) is a synthetic chemical widely used as a monomer for producing polycarbonate plastics. The present investigation employed an in-silico approach to identify BPA-responsive genes and comprehend the biological functions affected using in vitro studies. A Comparative Toxicogenomics Database search identified 29 BPA-responsive genes in cervical cancer (CC). Twenty-nine genes were screened using published datasets, and thirteen of those showed differential expression between normal and CC samples. Protein-Protein Interaction Networks (PPIN) analysis identified BIRC5, CASP8, CCND1, EGFR, FGFR3, MTOR, VEGFA, DOC2B, WNT5A, and YY1 as hub genes. KM-based survival analysis identified that CCND, EGFR, VEGFA, FGFR3, DOC2B, and YY1 might affect CC patient survival. SiHa and CaSki cell proliferation, migration, and invasion were all considerably accelerated by BPA exposure. Changes in cell morphology, remodeling of the actin cytoskeleton, increased number and length of filopodia, elevated intracellular reactive oxygen species and calcium, and lipid droplet accumulation were noted upon BPA exposure. BPA treatment upregulated the expression of epithelial to mesenchymal transition pathway members and enhanced the nuclear translocation of CTNNB1. We showed that the enhanced migration and nuclear translocation of CTNNB1 upon BPA exposure is a calcium-dependent process. The present study identified potential BPA-responsive genes and provided novel insights into the biological effects and mechanisms affected by BPA in CC. Our study raises concern over the use of BPA.

Ovarian tumor deubiquitinase 6A regulates cell proliferation via deubiquitination of nucleolin and caspase‑7

Most proteins maintain protein homeostasis via post‑translational modifications, including the ubiquitin‑proteasome system. Deubiquitinating enzymes (DUBs) have essential intercellular roles, such as responses to DNA damage, proteolysis and apoptosis. Therefore, it is important to understand DUB‑related diseases to identify DUBs that target abnormally regulated proteins in cells. Ovarian tumor deubiquitinase 6A (OTUD6A) was previously reported as a downregulated DUB in HCT116 cells with p53 knockdown. Therefore, it was expected that the relationship between OTUD6A and p53 would affect cell proliferation. In the present study, putative substrates of OTUD6A related to the p53 signaling pathway were identified. Application of liquid chromatography‑tandem mass spectrometry and proteomic analysis led to the identification of nucleolin (known to bind p53) as a binding protein. In addition, immunoprecipitation studies determined that caspase‑7, an apoptotic protein, is associated with p53 signaling and is regulated by OTUD6A. It was further identified that OTUD6A regulates the protein stability of nucleolin, but not caspase‑7. It was also demonstrated that OTUD6A acts as a respective DUB through the deubiquitination of K48‑linked polyubiquitin chain of nucleolin and the K63‑linked polyubiquitin chain of caspase‑7. Furthermore, overexpression of OTUD6A induced cell proliferation via enhancing cell cycle progression of MCF7 cells. Taken together, OTUD6A may be proposed as a target for anticancer therapy.

Screening of Therapeutic Candidate Genes of Quercetin for Cervical Cancer and Analysis of Their Regulatory Network

Purpose

To explore the therapeutic targets and regulatory mechanisms of the antitumor drug quercetin in the treatment of cervical cancer.

Methods

Cervical cancer (HeLa) cells were treated with quercetin and subjected to RNA sequencing using the BGISEQ-500 platform. By combined analysis of GEO database and RNA-seq results, the differentially expressed genes (DEGs) (namely, the genes in the GEO database that were upregulated/downregulated in cervical cancer compared with normal cervix and downregulated/upregulated after quercetin treatment) were identified. Functional enrichment and protein–protein interaction analyses were carried out for the DEGs. The candidate genes were identified using the Gentiscape2.2 and MCODE plug-ins for Cytoscape software, and the upstream miRNAs, lncRNAs, and circRNAs of the candidate genes were predicted using the online tools MirDIP, TarBase, and ENCORI. Finally, the regulatory network was constructed using Cytoscape software.

Results

Quercetin significantly inhibited the proliferation of cervical cancer cells. The combined analyses of the GEO database and RNA-seq results obtained 74 DEGs, and the functional enrichment analysis of the DEGs identified 861 biological processes, 32 cellular components, 50 molecular functions, and 56 KEGG pathways. Five therapeutic candidate genes, including EGFR, JUN, AR, CD44, and MUC1, were selected, and 10 miRNAs, 1 lncRNA, and 71 circRNAs upstream of these genes were identified. Finally, a lncRNA/circRNA-miRNA-mRNA-pathway regulatory network was constructed.

Conclusion

In this study, data mining was used to identify candidate genes and their regulatory network for the treatment of cervical cancer to provide a theoretical basis for targeted therapy of cervical cancer.

Expression Of Cyclin D1 Protein Isoforms And Its Prognostic Significance In Cervical Cancer

Introduction

Cyclin D1 had been associated with different clinical and pathological stages of cervical cancer; however, few studies had focused on its correlation with cervical cancer prognosis. Therefore, this study aimed to assess the expression of cyclin D1a and D1b in normal tissue, cervical cancer and cervical intraepithelial neoplasia and their effect on prognosis.

Methods

Expression of cyclin D1a and D1b was detected by immunohistochemical staining in 78 cases of primary cervical cancer, 40 cases of cervical intraepithelial neoplasia, and 40 cases of normal cervical tissue.

Results

No significant difference was observed in the expression of cyclin D1a between normal and cervical cancer tissues (P = 0.201); however, its expression was significantly higher in cervical cancer than in cervical intraepithelial neoplasia tissues (P = 0.000). Expression of cyclin D1b was higher in normal tissues than in cervical cancer tissues (P = 0.000). No significant difference was observed in the expression of cyclin D1a in cervical cancer tissues with respect to age, pathological type, clinical-stage, depth of tumor invasion, or presence of lymph node metastases (P = 0.111,0.119,0.539,0.084,0.539). COX survival analysis showed that lymph node metastasis might be an independent factor affecting postoperative recurrence (hazard risk [HR] = 0.240; 95% confidence interval [CI] = 0.968–30.156; P = 0.034).

Discussion

Cyclin D1a expression was associated with tumor tissue size and degree of differentiation. The expression of cyclin D1b in cervical cancer was associated with the presence of lymph node metastases. Cyclin D1a and D1b expression in cervical cancer tissue was significantly correlated. Cox survival analysis showed that the presence of lymph node metastases might serve as an independent factor affecting postoperative recurrence. The expression of cyclin D1a and D1b was not associated with cervical cancer prognosis.

Conclusion

Assessment of cyclin D1a and D1b expression in cervical cancer and cervical intraepithelial neoplasia revealed that cyclin D1 could not be used as a reference to assess cervical cancer patient prognosis.

Long non-coding RNA MEG3 suppresses survival, migration, and invasion of cervical cancer

Background

Long non-coding RNAs nowadays emerge as important biomarkers or potential therapeutic targets discussed in human cancers. Among them, maternally expressed gene 3 (MEG3) is known to be decreased in a variety of malignancies, and this affects tumor cellular proliferation, migration, and invasion.

Materials and methods

Quantitative real-time PCR was performed to detect the expression of MEG3 in normal cervical epithelium, cervical intraepithelial neoplasia, and cervical squamous cell carcinoma tissues. Gain-of-function and loss-of-function studies were carried out to determine the effect of MEG3 on cell survival, migration, and invasion, which was evaluated by CCK-8 assay, wound healing assay, and transwell assays. mRNA and protein expression of Rac1 were finally determined by quantitative real-time PCR and immunoblotting, respectively. In addition, rescue experiments were performed by overexpression of Rac1.

Results

The expression of MEG3 was downregulated in cervical intraepithelial neoplasia and squamous cell carcinoma tissues. Forced expression of MEG3 led to reduced abilities of cell survival. Overexpression of MEG3 also inhibited cell migration and invasion in vitro. Cell proliferation marker and EMT markers were changed consistently with the phenotype. In addition, Rac1 was inhibited by MEG3 overexpression at both transcriptional and translational levels. Also, Rac1 could rescue the phenotype caused by long non-coding RNA MEG3. And, it negatively correlated with MEG3 expression in cervical cancer (CC) tissues and cell lines.

Conclusion

Our findings revealed that MEG3 could negatively regulate CC cell survival, migration, and invasion. It might serve as an important target for CC treatment.

Nucleolin facilitates nuclear retention of an ultraconserved region containing TRA2β4 and accelerates colon cancer cell growth

Transcribed-ultraconserved regions (T-UCRs), which contain conserved sequences with 100% identity across human, rat and mouse species, are a novel category of functional RNAs. The human transformer 2β gene (TRA2B) encodes a UCR that spans exon 2 (276 bp) and its neighboring introns. Among five spliced RNA variants (TRA2β1-5) transcribed from the TRA2B gene, only TRA2β4 contains the conserved exon 2. TRA2β4 is overexpressed in colon cancer cells and accelerates cell growth by blocking the transcription of CDKN1A. However, the mechanisms underlying the overexpression of TRA2β4 in colon cancer cells are unknown. Using biotinylated RNA pull-down assays followed by liquid chromatography-mass spectrometric analysis, we identified nucleolin as a TRA2β4-binding protein. Knockdown of nucleolin reduced the nuclear retention of TRA2β4 and accelerated its degradation in the cytoplasm, whereas nucleolin overexpression increased TRA2β4 levels and its mitogenic activity. Nucleolin directly bound to TRA2β4 exon 2 via the glycine/arginine-rich (GAR) domain. Overexpression of GAR-deficient nucleolin failed to increase TRA2β4 expression and growth of colon cancer cells. RNA fluorescence in situ hybridization showed that TRA2β4 co-localized with nucleolin in nuclei but not with the mutant lacking GAR. Our results suggest that specific interactions between nucleolin and UCR-containing TRA2β4 may be associated with abnormal growth of colon cancer cells.

miR-202 inhibits the progression of human cervical cancer through inhibition of cyclin D1

The human cervical cancer (CC) acts as the most common one of women tumors. However, the pathological changes and molecular alterations of CC are not clear. It has been reported that miR-202 takes part in the development and progression of different tumors. The present study aims to detect the expression of miR-202 in 100 cases of CC tissues and cells, and then we continued to investigate the potential mechanisms of miR-202 in CC cells. In this work, we found that the expression of miR-202 is obviously decreased in both CC cell lines and tissues, and negatively related with the expression of cyclin D1 in SiHa, HeLa and Caski cells. In-vitro assay revealed that the ectopic expression of miR-202 suppressed the proliferation, migration and invasion of SiHa and HeLa cells. Additionally, the over-expression of miR-202 extremely affected the expression of cyclin D1 protein. Notably, the over-expression of cyclin D1 in SiHa and HeLa cells with miR-202 mimics attenuated the inhibitory effects of miR-202 on cell proliferation, migration and invasion. In conclusion, our study identified that miR-202 plays an important role in regulating cell proliferation, migration and invasion of CC by directly targeting cyclin D1, thus miR-202 may represent a potential therapeutic target for patients with cervical cancer.

New perspectives of physiological and pathological functions of nucleolin (NCL)

Nucleolin (NCL) is a multifunctional protein that mainly localized in the nucleolus, it is also found in the nucleoplasm, cytoplasm and cell membrane. The three main structural domains allow the interaction of NCL with different proteins and RNA sequences. Moreover, specific post-translational modifications and its shuttling property also contribute to its multifunctionality. NCL has been demonstrated to be involved in a variety of aspects such as ribosome biogenesis, chromatin organization and stability, DNA and RNA metabolism, cytokinesis, cell proliferation, angiogenesis, apoptosis regulation, stress response and microRNA processing. NCL has been increasingly implicated in several pathological processes, especially in tumorigenesis and viral infection, which makes NCL a potential target for the development of anti-tumor and anti-viral strategies. In this review, we present an overview on the structure, localizations and various functions of NCL, and further describe how the multiple functions of NCL are correlated to its multiple cellular distributions.

Knockdown of Tripartite-59 (TRIM59) Inhibits Cellular Proliferation and Migration in Human Cervical Cancer Cells

The tripartite motif (TRIM) family of proteins is a class of highly conservative proteins that have been implicated in multiple processes. TRIM59, one member of the TRIM family, has now received recognition as a key regulator in the development and progression of human diseases. However, its role in human tumorigenesis has remained largely unknown. In this study, the effects of TRIM59 expression on cell proliferation and migration were investigated in human cervical cancer cells. The expression of TRIM59 in clinical cervical cancer tissues and cervical cancer cells was initially determined by RT-PCR and Western blot. Specific shRNA against TRIM59 was then employed to knock down the expression of TRIM59 in cervical cancer lines HeLa and SiHa. The effects of TRIM59 knockdown on cell proliferation was assessed by MTT assay and colony formation assay. Transwell assay was conducted to reveal cell migration and invasion abilities before and after TRIM59 knockdown. Our results showed that the expression of TRIM59 was significantly elevated in cervical cancers. Knockdown of TRIM59 significantly inhibited cell proliferation and colony formation as well as cell migration and invasion abilities in cervical cancer HeLa and SiHa cells. Cell cycle progression analysis showed that TRIM59-depleted cells preferred to accumulate in the S phase. These data suggest that TRIM59 is a potential target that promotes the progression of cervical cancer.

The Critical Role of SRPK1 in EMT of Human Glioblastoma in the Spinal Cord

Up to now, the serine-arginine protein kinase 1 (SRPK1) has been suggested as an important signal mediator, which is implicated in the development of cancers. Unfortunately, some molecular pathways in SRPK1-mediated epithelial-mesenchymal transition (EMT) in human spinal glioblastoma have been not elucidated. In this work, we detected the expression of SRPK1 in human spinal glioblastoma tissues and GBM cell lines and analyzed the relevant molecular proteins using in vitro experiments, including RT-PCR, gene silencing, and Western blot. In this study, RT-PCR and Western blot revealed that the expression of SRPK1 mRNA and protein became higher in all six spinal glioblastoma specimens; however, its expression was low in matched normal specimens. We also demonstrated SRPK1 expression facilitated the proliferation of U87 and U251 cells and inhibited the apoptosis in U87 and U251 cells. Also, SRPK1 promoted the expression of EMT-regulating markers, involving N-cadherin, Snail, and MMP9 and decreased the expression of mesenchymal marker E-cadherin. Moreover, knockdown of SRPK1 significantly inhibited the expression levels of p-Akt rather than t-Akt. In conclusion, knockdown of SRPK1 inhibited glioblastoma cell proliferation, invasion, and EMT process via suppressing p-Akt signaling pathway. This study also lays a new foundation for the clinically biological treatment.

MiR-195 inhibits the proliferation of human cervical cancer cells by directly targeting cyclin D1

MicroRNAs are important regulators of multiple cellular processes, and aberrant miRNA expression has been observed in human cervical cancer (CC). The present study was to evaluate the level of miR-195 and cyclin D1 in CC tissues and cells. We further investigated the molecular mechanisms of miR-195 and cyclin D1 in CC cell lines HeLa and SiHa. Here, we found that miR-195 expression was down-regulated in CC tissues, and HeLa and SiHa cells (all p < 0.001). By contrast, cyclin D1 was up-regulated. Furthermore, the expression of miR-195 was inversely proportional to that of cyclin D1 mRNA or protein (p = 0.013, p = 0.015, respectively). In vitro studies demonstrated that the overexpression of miR-195 played a suppressor role in the proliferation of HeLa and SiHa cells and promoted cell apoptosis. Luciferase reporter assays confirmed that miR-195 binding to the 3'-UTR regions of cyclin D1 inhibited the expression of cyclin D1 in HeLa and SiHa cells. However, the inhibitor of miR-195 promoted the expression of cyclin D1 and cell proliferation. In conclusion, our data suggest that miR-195 may have the potential role in treatment of CC patients, as well as miR-195 is a novel regulator of invasiveness and tumorigenicity in CC cells by targeting cyclin D1. MiR-195/cyclin D1 pathway may be a useful therapeutic agent in CC patients.

Proliferating Cell Nuclear Antigen Has an Association with Prognosis and Risks Factors of Cancer Patients: a Systematic Review

Proliferating cell nuclear antigen (PCNA) is reported as a famous marker in various tumors. A couple of articles have been published about the clinical function of PCNA on cancer progression; however, these results are conflicting in some degree. Thus, it is crucial to perform a systematic review and meta-analysis to identify their real actions. Here, we took cervical cancer and glioma as example and then pooled hazard ratios (HRs) or odds ratios (ORs) with 95 % confidence intervals (95 % CIs). In the present study, the PCNA expression in cervical cancer and gliomas patients was both correlated with 5-year-overall survival (OS) (HR = 4.41, 95 % CI 2.71-7.17, p = 0.000; HR = 4.40, 95 % CI 3.00-6.47, p = 0.000; respectively). In addition, a fixed effect model revealed a significant association between PCNA and FIGO stage (OR = 4.48, 95 % CI 3.48-5.77, p = 0.000) or WHO grade (OR = 5.64, 95 % CI 4.15-7.68, p = 0.000), rather than age (OR = 1.01, 95 % CI 0.71-1.43, p = 0.957; OR = 1.00, 95 % CI 0.80-1.24, p = 0.989; respectively). No heterogeneity was observed across all studies. According to funnel plot, no publication bias was reported. In conclusion, our systematic review suggests that PCNA expression is significantly associated with poor 5-year survival, advanced stage or higher WHO grade, which might be suggested as a useful prognostic and diagnostic biomarker, or an effective therapy target in cervical cancer, gliomas, or even more cancers.