Cofilin-2 Acts as a Marker for Predicting Radiotherapy Response and Is a Potential Therapeutic Target in Nasopharyngeal Carcinoma

A glimpse into cofilin-1 role in cancer therapy: A potential target to improve clinical outcomes?

Cofilin-1 (CFL1) modulates dynamic actin networks by severing and enhancing depolymerization. The upregulation of cofilin-1 expression in several cancer types is associated with tumor progression and metastasis. However, recent discoveries indicated relevant cofilin-1 functions under oxidative stress conditions, interplaying with mitochondrial dynamics, and apoptosis networks. In this scenario, these emerging roles might impact the response to clinical therapy and could be used to enhance treatment efficacy. Here, we highlight new perspectives of cofilin-1 in the therapy resistance context and discussed how cofilin-1 is involved in these events, exploring aspects of its contribution to therapeutic resistance. We also provide an analysis of CFL1 expression in several tumors predicting survival. Therefore, understanding how exactly coflin-1 plays, particularly in therapy resistance, may pave the way to the development of treatment strategies and improvement of patient survival.

Downregulation of Circular RNA PSEN1 ameliorates ferroptosis of the high glucose treated retinal pigment epithelial cells via miR-200b-3p/cofilin-2 axis

Ferroptosis is a form of programmed cell death that participates in the progression of numerous diseases. Long noncoding RNAs (lncRNAs) are dysregulated in diabetic retinopathy (DR). However, the role of lncRNAs in DR-induced ferroptosis is unclear. Adult retinal pigment epithelial cell line-19 (ARPE19) cells were treated with a high concentration of glucose (high glucose, HG) to mimic DR in vitro. The intracellular contents of glutathione, malondialdehyde, and ferrous ions were analyzed using the corresponding kits. The MTT assay was performed to measure the cell survival rate, and cell death was determined using propidium iodide and terminal deoxynucleotidyl transferase dUTP nick end labeling staining assays. Western blotting was conducted to detect the protein levels of GPX4, SLC7A11, and TFR1. The targeting relationships were verified using luciferase reporter and RNA pull-down assays. circ-PSEN1 was upregulated in HG-treated ARPE19 cells and showed high resistance to RNase R and Act D. Inhibition of circ-PSEN1 in ARPE19 cells ameliorated the ferroptosis induced by HG was ameliorated, as evidenced by changes in the ferroptosis-related biomarkers/genes and decreased cell death. Subsequently, circ-PSEN1 acted as a sponge for miR-200b-3p. Inhibition of miR-200b-3p partially reversed the effects of circ-PSEN1 on ferroptosis. Furthermore, cofilin-2 (CFL2) was the target gene of miR-200b-3p, and it abrogated the inhibitory effect of miR-200b-3p on ferroptosis. Taken together, the findings indicate that knockdown of circ-PSEN1 can mitigate ferroptosis of ARPE19 cells induced by HG via the miR-200b-3p/CFL2 axis.

Circ_0008673 regulates breast cancer malignancy by miR-153-3p/CFL2 axis

BACKGROUND

Breast cancer is an aggressive tumor, which poses a heavy burden to human health. Circular RNAs have been involved in the pathogenesis of breast cancer. This study aims to investigate whether circ_0008673 mediates breast cancer malignant progression by microRNA-153-3p (miR-153-3p)/cofilin 2 (CFL2) pathway.

METHODS

The RNA levels of circ_0008673, miR-153-3p and CFL2 were detected by quantitative real-time polymerase chain reaction (qRT-PCR). The protein expression of CFL2, E-cadherin and N-cadherin was determined by western blot analysis. Cell proliferation was demonstrated through cell counting kit-8 and cell colony-formation assays. Cell apoptosis was detected by flow cytometry analysis. Cell migratory and invasive capacities were determined by transwell assay. The associated relationship between miR-153-3p and circ_0008673 or CFL2 was predicted by online databases, and testified by dual-luciferase reporter and RNA immunoprecipitation assays. In vivo assay was employed to demonstrate the effects of circ_0008673 silencing on tumor formation in vivo.

RESULTS

Circ_0008673 and CFL2 expressions were upregulated, while miR-153-3p expression was downregulated in breast cancer tissues and cells compared with adjacent normal breast tissues and cells, respectively. Circ_0008673 overexpression promoted cell proliferation, migration and invasion, and repressed cell apoptosis, while circ_0008673 silencing had opposite effects. Additionally, circ_0008673 served as a sponge of miR-153-3p. And circ_0008673 was proved to regulate breast cancer cell malignancy by sponging miR-153-3p. MiR-153-3p was found to modulate breast cancer cell carcinogenesis via targeting CFL2. Furthermore, circ_0008673 silencing repressed tumor growth in vivo.

CONCLUSION

Circ_0008673 promoted breast cancer progression by upregulating CFL2 expression through sponging miR-153-3p. This study provides a theoretical basis for researching circRNA-directed treatment of breast cancer.

Ionizing Radiation Protein Biomarkers in Normal Tissue and Their Correlation to Radiosensitivity: A Systematic Review

Background and objectives: Exposure to ionizing radiation (IR) has increased immensely over the past years, owing to diagnostic and therapeutic reasons. However, certain radiosensitive individuals show toxic enhanced reaction to IR, and it is necessary to specifically protect them from unwanted exposure. Although predicting radiosensitivity is the way forward in the field of personalised medicine, there is limited information on the potential biomarkers. The aim of this systematic review is to identify evidence from a range of literature in order to present the status quo of our knowledge of IR-induced changes in protein expression in normal tissues, which can be correlated to radiosensitivity. Methods: Studies were searched in NCBI Pubmed and in ISI Web of Science databases and field experts were consulted for relevant studies. Primary peer-reviewed studies in English language within the time-frame of 2011 to 2020 were considered. Human non-tumour tissues and human-derived non-tumour model systems that have been exposed to IR were considered if they reported changes in protein levels, which could be correlated to radiosensitivity. At least two reviewers screened the titles, keywords, and abstracts of the studies against the eligibility criteria at the first phase and full texts of potential studies at the second phase. Similarly, at least two reviewers manually extracted the data and accessed the risk of bias (National Toxicology Program/Office for Health Assessment and Translation—NTP/OHAT) for the included studies. Finally, the data were synthesised narratively in accordance to synthesis without meta analyses (SWiM) method. Results: In total, 28 studies were included in this review. Most of the records (16) demonstrated increased residual DNA damage in radiosensitive individuals compared to normo-sensitive individuals based on γH2AX and TP53BP1. Overall, 15 studies included proteins other than DNA repair foci, of which five proteins were selected, Vascular endothelial growth factor (VEGF), Caspase 3, p16^INK4A (Cyclin-dependent kinase inhibitor 2A, CDKN2A), Interleukin-6, and Interleukin-1β, that were connected to radiosensitivity in normal tissue and were reported at least in two independent studies. Conclusions and implication of key findings: A majority of studies used repair foci as a tool to predict radiosensitivity. However, its correlation to outcome parameters such as repair deficient cell lines and patients, as well as an association to moderate and severe clinical radiation reactions, still remain contradictory. When IR-induced proteins reported in at least two studies were considered, a protein network was discovered, which provides a direction for further studies to elucidate the mechanisms of radiosensitivity. Although the identification of only a few of the commonly reported proteins might raise a concern, this could be because (i) our eligibility criteria were strict and (ii) radiosensitivity is influenced by multiple factors. Registration: PROSPERO (CRD42020220064).

Silencing hTERT attenuates cancer stem cell-like characteristics and radioresistance in the radioresistant nasopharyngeal carcinoma cell line CNE-2R

Objective: This study aimed to explore the effect of silencing hTERT on the CSC-like characteristics and radioresistance of CNE-2R cells.

Results: Silencing hTERT suppressed CNE-2R cell proliferation and increased the cell apoptosis rate and radiosensitivity in vitro. Moreover, it could also inhibit the growth of xenografts and increase the apoptosis index and radiosensitivity in vivo. Further study discovered that after silencing hTERT, telomerase activity in CNE-2R cells was markedly suppressed, along with remarkably down-regulated stem cell-related protein levels both in vitro and in vivo.

Conclusion: Silencing hTERT can suppress the CSC-like characteristics of CNE-2R cells to enhance their radiosensitivity, revealing that hTERT may become a potential target for treating radioresistant NPC.

Methods: An RNAi lentiviral vector specific to the hTERT gene was constructed to infect CNE-2R cells, the hTERT silencing effect was verified through qPCR and Western blot assays, and telomerase activity was detected by PCR-ELISA. Moreover, radiosensitivity in vitro was detected through colony formation assays, CCK-8 assays and flow cytometry. Tumor growth and radioresistance were also evaluated using xenograft models, while the apoptosis index in xenografts was measured through TUNEL assay. Levels of stem cell-related proteins were determined in vitro and in vivo.

Oral Soft Tissue Regeneration Using Nano Controlled System Inducing Sequential Release of Trichloroacetic Acid and Epidermal Growth Factor

BACKGROUND

The effect of nano controlled sequential release of trichloroacetic acid (TCA) and epidermal growth factor (EGF) on the oral soft tissue regeneration was determined.

METHODS

Hydrophobically modified glycol chitosan (HGC) nano controlled system was developed for the sequential release of TCA and EGF, and the release pattern was identified. The HGC-based nano controlled release system was injected into the critical-sized defects created in beagles' palatal soft tissues. The palatal impression and its scanned body was obtained on various time points post-injection, and the volumetric amount of soft tissue regeneration was compared among the three groups: CON (natural regeneration control group), EXP1 (TCA-loaded nano controlled release system group), EXP2 (TCA and EGF individually loaded nano controlled release system). DNA microarray analysis was performed and various soft tissue regeneration parameters in histopathological specimens were measured.

RESULTS

TCA release was highest at Day 1 whereas EGF release was highest at Day 2 and remained high until Day 3. In the volumetric measurements of impression body scans, no significant difference in soft tissue regeneration between the three groups was shown in two-way ANOVA. However, in the one-way ANOVA at Day 14, EXP2 showed a significant increase in soft tissue regeneration compared to CON. High correlation was determined between the histopathological results of each group. DNA microarray showed up-regulation of various genes and related cell signaling pathways in EXP2 compared to CON.

CONCLUSION

HGC-based nano controlled release system for sequential release of TCA and EGF can promote regeneration of oral soft tissue defects.

Identification and interaction analysis of key miRNAs in medullary thyroid carcinoma by bioinformatics analysis

Medullary thyroid carcinoma (MTC) is an endocrine tumor and comprises 5–10% of all primary thyroid malignancies. However, the biomechanical contribution to the development and progression of MTC remains unclear. In this study, To discover the key microRNAs (miRNAs or miRs) and their potential roles in the tumorigenesis of MTC, the microarray datasets GSE97070, GSE40807 and GSE27155 were analyzed. The datasets were downloaded from the Gene Expression Omnibus (GEO) database. The differentially expressed miRNAs (DEMs) and genes (DEGs) were accessed by R. Targets of DEMs and predicted using starBase, and functional and pathway enrichment analyses were performed using Metascape. A protein-protein interaction (PPI) network and an analysis of modules were constructed using NetworkAnalyst. Finally, a network was constructed to show the regulatory association between transcription factors (TFs), DEMs and downstream genes. A total of 5 DEMs were found both in GSE97070 and GSE40807, including 3 upregulated DEMs and 2 downregulated DEMs. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses from Metascape revealed that the target genes of upregulated DEMs were significantly enriched in adherens junction, kinase and protein binding, while the target genes of downregulated DEMs were mainly involved in non-canonical Wnt signaling pathway and RNA transport. From the PPI network, 13 nodes were screened as hub genes. Pathway enrichment analysis revealed that the top 5 modules were mostly enriched in the neurotrophin signaling pathway, mRNA surveillance pathway and MAPK signaling pathway. In addition, the TF-DEMs-target gene and DEGs regulatory network revealed that 17 TFs regulated 2 miRNAs, including upregulated or downregulated DEMs, CREB1 regulated all upregulated DEMs, and TGFB1 was an activator of hsa-miR-199a-3p and a repressor of hsa-miR-429. Taken together, the present study identified several miRNAs and potential biological mechanisms involved in the tumorigenesis of MTC. This study identified the key DEMs and potential mechanisms underlying the development of MTC, and provided a series of biomarkers and targets for the management of MTC.

Characterization of mRNA Expression and Endogenous RNA Profiles in Bladder Cancer Based on The Cancer Genome Atlas (TCGA) Database

Background

Bladder cancer is a multifactorial disease with increasing incidence and mortality. Genetic alterations and altered expressions of mRNAs, long non-coding RNAs (lncRNAs), and miRNAs have been shown to play important roles in the tumorigenesis of bladder cancer. However, the functions of key RNAs and their regulatory network in bladder cancer are still to be elucidated.

Material/Methods

RNA profiles were downloaded from The Cancer Genome Atlas (TCGA) database. The differentially expressed mRNAs, lncRNAs, and miRNAs in bladder cancer were acquired through analyses of data from 414 bladder cancer tissues and 19 normal bladder tissues. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis was performed by using “DAVID6.8” and the R package “ClusterProfile”. Protein–protein interaction and competing endogenous RNA (ceRNA) networks were constructed by using “STRING” database and Cytoscape 3.6.2. Based on the clinical data and Cox regression, a prognosis model was established, and survival analysis was performed.

Results

A total of 1819 mRNAs, 659 lncRNAs, and 160 miRNAs were identified as significantly differentially expressed in bladder cancer of which 52 mRNAs, 58 lncRNAs, and 22 miRNAs were incorporated in the ceRNA network. CFL2 and TPM2 were found to be downregulated and showed significant correlation to each other in bladder cancer. HOXB5 and 6 lncRNAs (ADAMTS9-AS1, AC112721.1, LINC00460, AC110491.1, LINC00163, and HCG22) were strongly associated with high-grade, disease stages, and overall survival.

Conclusions

In this study, we have identified differentially expressed mRNAs, lncRNAs, and miRNAs in bladder cancer which were strongly associated with oncogenesis and prognosis. Further experimental studies are necessary to validate these results.

Expression of vimentin in nasopharyngeal carcinoma and its possible molecular mechanism: A study based on immunohistochemistry and bioinformatics analysis

BACKGROUND

Although previous researchers have analyzed the expression level of vimentin in nasopharyngeal carcinoma (NPC), the sample size of each study was too small, and there was no further in-depth study utilizing microarray and RNA-sequencing data. More importantly, the role and molecular mechanism of vimentin in NPC have not yet been addressed comprehensively. Accordingly, the aim of the present research was to conduct a full exploration of the clinical significance of vimentin in NPC in a large sample size.

MATERIALS AND METHODS

Immunohistochemistry was used to test the expression of vimentin in clinical samples. Data from relevant microarray and RNA-sequencing datasets were screened and extracted to explore the clinical role of vimentin in NPC. Subsequently, vimentin-related signaling pathways were investigated via in-silico approaches.

RESULTS

The clinical immunohistochemistry detection showed the positive expression ratio of vimentin was 24.6% (14/57) of the NPC specimens, whereas vimentin expression was negative in nasopharyngitis (NPG) tissues (0/20, P = 0.016). The mRNA and protein levels of vimentin were both remarkably up-regulated in NPC based on 196 and 1566 cases, respectively. The protein level of vimentin was also a risky factor for the prognosis prediction of NPC with the hazard ratios (HR) being 3.831. Gene ontology (GO) and kyoto encyclopedia of genes and genomes (KEGG) analyses, the localization of vimentin was in both the cytoplasm and the cytoskeleton, and vimentin was involved in the regulation of molecular function, the execution phase of apoptosis, and the regulation of cellular component organization.

CONCLUSION

The high expression of vimentin plays a pivotal role in the development and poor progression of NPC, which indicates that vimentin may be an effective predictive indicator for NPC.