The role of EGFR/PI3K/Akt/cyclinD1 signaling pathway in acquired middle ear cholesteatoma

Expression and Regulatory Mechanisms of MicroRNA in Cholesteatoma: A Systematic Review

Cholesteatoma is a temporal bone disease characterized by dysfunctions of keratinocytes. MicroRNAs (miRNAs) are evolutionary conserved noncoding RNAs that regulate mRNA expression. They can be packaged into exosomes and transported to target cells that can be used in the future therapy of cholesteatoma. This study aimed to collect knowledge on the role of miRNAs and exosomal miRNAs in cholesteatoma and was conducted according to the PRISMA guidelines for systematic reviews. Four databases were screened: Pubmed/MEDLINE, Web of Science, Scopus, and the Cochrane Library. The last search was run on the 6th of June 2023. We included full-text original studies written in English, which examined miRNAs in cholesteatoma. The risk of bias was assessed using the Office of Health Assessment and Translation (OHAT) Risk of Bias Rating Tool, modified for the needs of this review. We identified 118 records and included 18 articles. Analyses revealed the downregulation of exosomal miR-17 as well as miR-10a-5p, miR-125b, miR-142-5p, miR34a, miR-203a, and miR-152-5p and the overexpression of exosomal miR-106b-5p as well as miR-1297, miR-26a-5p, miR-199a, miR-508-3p, miR-21-3p, miR-584-5p, and miR-16-1-3p in cholesteatoma. The role of differentially expressed miRNAs in cholesteatoma, including cell proliferation, apoptosis, the cell cycle, differentiation, bone resorption, and the remodeling process, was confirmed, making them a potential therapeutic target in this disease.

MUC1 induces the accumulation of Foxp3+ Treg cells in the tumor microenvironment to promote the growth and metastasis of cholangiocarcinoma through the EGFR/PI3K/Akt signaling pathway

Tumor microenvironment (TME) plays an important role in the progression of cholangiocarcinoma. This study aims to explore whether Mucin 1 (MUC1) regulates Foxp3⁺ Treg cells in the TME of cholangiocarcinoma through the epidermal growth factor receptor (EGFR)/phosphatidylinositol-3-kinase (PI3K)/Akt signaling pathway. High-throughput sequencing dataset in the GEO database combined with GeneCards and Phenolyzer databases was used to obtain key genes in cholangiocarcinoma, followed by downstream pathway prediction. The relationship among MUC1, EGFR, and PI3K/Akt signaling pathway was explored. CD4⁺ T cells extracted from peripheral blood were induced to differentiate into Treg cells, followed by co-culture with cholangiocarcinoma cells. A mouse model was constructed to detect the role of MUC1 in the accumulation of Foxp3⁺ Treg cells, malignant phenotypes of cholangiocarcinoma, and tumorigenesis in vivo. MUC1, highly expressed in cholangiocarcinoma, might be involved in cholangiocarcinoma development. MUC1 interacted with the EGFR to activate the EGFR/PI3K/Akt signaling pathway. MUC1 overexpression could activate the EGFR/PI3K/Akt signaling pathway, which promoted the accumulation of Foxp3⁺ Treg cells in the TME and the malignant phenotypes of cholangiocarcinoma cells both in vitro and in vivo and enhanced tumorigenesis in vivo. MUC1 may interact with EGFR to activate the EGFR/PI3K/Akt signaling pathway, which induces the accumulation of Foxp3⁺ Treg cells, enhancing the malignant phenotypes of cholangiocarcinoma cells and tumorigenesis in vivo and ultimately augmenting cholangiocarcinoma growth and metastasis.

A fluorescent photoimmunoconjugate for imaging of cholesteatoma

Cholesteatoma is a potentially serious complication of chronic ear infections and requires surgical intervention for definitive management. Long-term complications include a frequent need for repeat surgical intervention for disease recurrence, and techniques to improve efficacy of single-stage surgery are an important area of continued research. This study investigates a novel application of the photosensitizer immune conjugate (PIC) cetuximab-benzoporphyrin derivative (Cet-BPD) for in vitro localization of human cholesteatoma tissue, coupled with an in vivo safety study for middle ear application of Cet-BPD in a murine model. In fresh human cholesteatoma tissues, Cet-BPD demonstrates selective localization to the hyperplastic squamous cell tissue associated with cholesteatoma, without localizing to other tissues such as middle ear mucosa. Applied to the murine middle ear, Cet-BPD does not demonstrate any deleterious effect on murine hearing when assessed by any of auditory brainstem response (ABR) thresholds, distortion product otoacoustic emission thresholds, or ABR wave I amplitudes. These findings demonstrate the technical promise and encouraging safety profile for the use of PICs for intraoperative localization and treatment of cholesteatoma.

Microarray analysis and functional prediction of differentially expressed circular RNAs in acquired middle ear cholesteatoma

BACKGROUND

Middle ear cholesteatoma is characterized by hyper-proliferation of keratinocytes. Circular RNA (circRNA) plays an essential role in the pathogenesis of many proliferative diseases. However, the role of circRNA in the etiopathogenesis of middle ear cholesteatoma is rarely investigated so far. We aimed to investigate the differential expression profiling of circRNAs between acquired middle ear cholesteatoma and normal skin, and to identify potential circRNAs contributing to the etiopathogenesis of middle ear cholesteatoma. Microarray analysis and functional prediction were performed to investigate the circRNA expression profiling between middle ear cholesteatoma and normal skin. Validation of differentially expressed circRNAs was conducted by qRT-PCR. Prediction of m⁶A modification was also carried out.

RESULTS

Microarray analysis displayed that totally 93 up-regulated and 85 down-regulated circRNAs were identified in middle ear cholesteatoma. Through validation, expressions of hsa_circRNA_104327 and hsa_circRNA_404655 were significantly higher, while hsa_circRNA_000319 was significantly down-regulated in cholesteatoma. GO classification, KEGG pathway, and ceRNA network analyses suggested that these differentially expressed circRNAs might play important roles in the etiopathogenesis of middle ear cholesteatoma. Prediction of m⁶A modification exhibited that hsa_circRNA_000319 possessed 4 m⁶A sites with very high confidence, and hsa_circRNA_404655 had 3 m⁶A sites with high confidence.

CONCLUSIONS

Our study revealed that these differentially expressed circRNAs might contribute to the etiopathogenesis of middle ear cholesteatoma. Further researches should be conducted to investigate the exact mechanism of these differentially expressed circRNAs in the etiopathogenesis of middle ear cholesteatoma. Targeting on these circRNAs may provide a new strategy for middle ear cholesteatoma therapy in the future.

Seasonal expressions of ERα, ERβ, EGF, EGFR, PI3K and Akt in the scent glands of the muskrats (Ondatra zibethicus)

Epidermal growth factor (EGF) is an important autocrine and/or paracrine mediator of steroid hormones to stimulate growth and differentiation in mammals. The aim of this study is to investigate seasonal expressions of estrogen receptor α (ERα), estrogen receptor β (ERβ), EGF, epidermal growth factor receptor (EGFR), phosphatidylinositol 3-kinase (PI3K) and protein kinase B (Akt) in the scent glands of the muskrats during the breeding and non-breeding seasons. Histologically, three types of cells including the glandular cells, interstitial cells and epithelial cells were identified in the scent glands in both seasons. Immunohistochemical results showed that ERα, ERβ, EGF, EGFR, PI3K and Akt were presented in the different types of cells of the scent glands during the breeding and non-breeding seasons. Transcriptome data of the scent glandular tissues from muskrats in the breeding and non-breeding seasons showed that differential seasonal changes might be related to the estrogen-EGFR signaling pathway. The gene expression levels of ERα, ERβ, EGF, EGFR, PI3K were increased, while the gene expression level of Akt were decreased in the breeding season than those in the non-breeding season. Besides, the concentrations of 17β-estradiol (E₂) in the serum and the scent glandular tissues were remarkably higher in the breeding season than those of the non-breeding season. Taken together, our results suggested that EGFR signaling pathway may coordinate with ERs signaling to regulate the seasonal changes of the scent glandular functions.

Hsa_circ_0074491 regulates the malignance of cholesteatoma keratinocytes by modulating the PI3K/Akt pathway by binding to miR-22-3p and miR-125a-5p: An observational study

Cholesteatoma is a benign cystic lesion that can continue to grow like a tumor. Circular ribonucleic acid (RNA) hsa_circ_0074491 (circ_0074491) has been reported to be down-regulated in cholesteatoma tissues. However, the role and regulatory mechanism of circ_0074491 in the growth of cholesteatoma are unclear.The expression of circ_0074491, microRNA (miR)-22-3p, and miR-125a-5p in cholesteatoma tissues was detected by quantitative real-time polymerase chain reaction. The proliferation, cell cycle, apoptosis, migration, and invasion of cholesteatoma keratinocytes were evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, plate clone, flow cytometry, or transwell assays. Several protein levels were examined by western blotting. The targeting relationship between miR-22-3p or miR-125a-5p and circ_0074491 was verified via dual-luciferase reporter and RNA pull-down assays.We observed the downregulation of circ_0074491 in cholesteatoma tissues. Furthermore, circ_0074491 knockdown facilitated cell proliferation, migration, invasion, and repressed cell apoptosis in cholesteatoma keratinocytes. Circ_0074491 was verified as a decoy for miR-22-3p and miR-125a-5p in cholesteatoma keratinocytes. Both miR-22-3p and miR-125a-5p silencing reversed the impacts of circ_0074491 silencing on proliferation, apoptosis, migration, and invasion of cholesteatoma keratinocytes. Also, circ_0074491 knockdown activated the PI3K/Akt pathway in cholesteatoma keratinocytes via miR-22-3p and miR-125a-5p.Circ_0074491 played a suppressive role in cholesteatoma through inactivating the PI3K/Akt pathway via binding to miR-22-3p and miR-125a-5p, which provided a novel evidence for the involvement of circRNA in the development of cholesteatoma.

Purpurin, a anthraquinone induces ROS-mediated A549 lung cancer cell apoptosis via inhibition of PI3K/AKT and proliferation

OBJECTIVES

In this study, we sought to evaluate purpurin, a natural biomedicine and a potential inhibitor in decreasing the growth rate of lung cancer cells by modulating the role of PI3K/AKT signalling-associated proliferation and apoptosis.

METHODS

A549 cells were treated with purpurin (30 μM) for 24 and 48 h incubation, respectively, and it has been analysed for cytotoxicity, ROS-mediated apoptotic staining. Moreover, purpurin-mediated lipid peroxidation and GSH were measured by biochemical estimation. Furthermore, PI3K/AKT signalling-mediated cell proliferation and apoptotic gene expression done were by western blot.

KEY FINDINGS

In this study, we observed that purpurin could effectively kill A549 cancer cell lines and leads to cell death, thus conforming increased cytotoxicity, production of ROS-mediated enhancement of lipid peroxidation, nuclear fragmentation and apoptosis. Moreover, the GSH content of A549 cell lines was also diminished after treatment with purpurin. This study demonstrates that purpurin inhibits the phosphorylated PI3K/AKT molecules mediated cyclin-D1 and PCNA, thereby inducing apoptosis by observing increased proapoptotic mediators Bax, cleaved PARP, cytochrome-c, caspase-9 and caspase-3; and decreased Bcl-2 expression in the lung cancer cell lines.

CONCLUSION

This result concluded that purpurin eliminates the A549 lung cancer cells by blocking the PI3K/AKT pathway thereby inducing apoptosis.

miR-338-3p inhibits cell growth, invasion, and EMT process in neuroblastoma through targeting MMP-2

This study aimed to explore the regulatory mechanisms of miR-338-3p and matrix metalloproteinase-2 (MMP-2) in neuroblastoma. Putative target interaction regions of miR-338-3p on MMP-2 were predicted by miRcode and miRbase bioinformatics tools. Relative expression of miRNA-338-3p and MMP-2 in neuroblastoma tissues and GI-LI-N and SK-N-SH cells was determined by reverse transcription polymerase chain reaction experiment. Furthermore, the cell proliferation was determined by Cell Counting Kit-8 assay, the cell apoptosis rate was analyzed by flow cytometry assay, and the cell invasion was evaluated by transwell assay. miR-338-3p expression was downregulated, whereas MMP-2 expression was upregulated in metastasis tissue site compared to that in primary tissue site in total. Furthermore, miR-338-3p overexpression suppressed proliferation, invasion, and epithelial-mesenchymal transition (EMT) of neuroblastoma cells but promoted apoptosis, and the knockdown of MMP-2 triggered similar effects. Furthermore, MMP-2 was directly targeted by miR-338-3p, and overexpression of MMP-2 rescued the inhibitory effects of miR-338-3p on human neuroblastoma cell progression. Collectively, these data demonstrated that miR-338-3p could suppress cell growth, invasion, and EMT pathway and induce apoptosis in neuroblastoma cells by targeting MMP-2. MiR-338-3p sponged MMP-2 to regulate the PI3K/AKT pathway in human neuroblastoma cells.

Prazosin inhibits the proliferation, migration and invasion, but promotes the apoptosis of U251 and U87 cells via the PI3K/AKT/mTOR signaling pathway

Prazosin, an α-adrenergic receptor antagonist, is used to treat mild to moderate hypertension. It has recently been discovered that α-adrenergic receptors may have potential antitumor properties. Therefore, in the present study, the effect of prazosin on human glioblastoma and the underlying mechanism were investigated. Human glioblastoma U251 and U87 cells were treated with different concentrations of prazosin, and a Cell Counting Kit-8 assay was performed to investigate the effects of prazosin on cell proliferation. Transwell migration and invasion assays were used to assess the effects of prazosin on cell migration and invasion. Prazosin-induced apoptosis in U251 and U87 cells was detected by flow cytometry, and the protein expression levels of anti-apoptotic proteins and proteins related to the PI3K/AKT/mTOR signaling pathway were detected by western blotting. The results suggested that following treatment with prazosin, the proliferation, migration and invasion of U251 and U81 cells were decreased. By contrast, U251 and U81 cell apoptosis, as well as the protein expression levels of Bax and active Caspase-3 were increased after prazosin treatment (P<0.05). Bcl-2 levels were also decreased after prazosin treatment (P<0.05). Additionally, the expression of phosphorylated (p)-AKT and p-mTOR, P70 and cyclin D1 were decreased in U251 and U81 cells following prazosin treatment (P<0.05). The present study suggested that prazosin may suppress glioblastoma progression by downregulating the activity of the PI3K/AKT/mTOR signaling pathway.

Arsenic Stimulates Myoblast Mitochondrial Epidermal Growth Factor Receptor to Impair Myogenesis

Arsenic exposure impairs muscle metabolism, maintenance, progenitor cell differentiation, and regeneration following acute injury. Low to moderate arsenic exposures target muscle fiber and progenitor cell mitochondria to epigenetically decrease muscle quality and regeneration. However, the mechanisms for how low levels of arsenic signal for prolonged mitochondrial dysfunction are not known. In this study, arsenic attenuated murine C2C12 myoblasts differentiation and resulted in abnormal undifferentiated myoblast proliferation. Arsenic prolonged ligand-independent phosphorylation of mitochondrially localized epidermal growth factor receptor (EGFR), a major driver of proliferation. Treating cells with a selective EGFR kinase inhibitor, AG-1478, prevented arsenic inhibition of myoblast differentiation. AG-1478 decreased arsenic-induced colocalization of pY845EGFR with mitochondrial cytochrome C oxidase subunit II, as well as arsenic-enhanced mitochondrial membrane potential, reactive oxygen species generation, and cell cycling. All of the arsenic effects on mitochondrial signaling and cell fate were mitigated or reversed by addition of mitochondrially targeted agents that restored mitochondrial integrity and function. Thus, arsenic-driven pathogenesis in skeletal muscle requires sustained mitochondrial EGFR activation that promotes progenitor cell cycling and proliferation at the detriment of proper differentiation. Collectively, these findings suggest that the arsenic-activated mitochondrial EGFR pathway drives pathogenic signaling for impaired myoblast metabolism and function.

Epidermal growth factor regulates the development of stem and progenitor Leydig cells in rats

Epidermal growth factor (EGF) has many physiological roles. However, its effects on stem and progenitor Leydig cell development remain unclear. Rat stem and progenitor Leydig cells were cultured with different concentrations of EGF alone or in combination with EGF antagonist, erlotinib or cetuximab. EGF (1 and 10 ng/mL) stimulated the proliferation of stem Leydig cells on the surface of seminiferous tubules and isolated CD90⁺ stem Leydig cells and progenitor Leydig cells but it blocked their differentiation. EGF also exerted anti‐apoptotic effects of progenitor Leydig cells. Erlotinib and cetuximab are able to reverse EGF‐mediated action. Gene microarray and qPCR of EGF‐treated progenitor Leydig cells revealed that the down‐regulation of steroidogenesis‐related proteins (Star and Hsd3b1) and antioxidative genes. It was found that EGF acted as a proliferative agent via increasing phosphorylation of AKT1. In conclusion, EGF stimulates the proliferation of rat stem and progenitor Leydig cells but blocks their differentiation.

Low expression of microRNA-125b enhances the expression of STAT3 and contributes to cholesteatoma growth

Introduction

MicroRNA-125b has been found to be down-regulated in many types of malignant tumours and diseases with excessive proliferation of keratinocytes, such as cutaneous squamous cell carcinoma and psoriasis. Cholesteatoma, which is mainly composed of keratinocytes, also has characteristics of abnormal proliferation similar to a malignant tumour. However, the expression and regulatory mechanisms of miR-125b and its downstream genes in cholesteatoma have not been clarified.

Material and methods

Real time fluorescence quantitative PCR was applied to detect the expression of miR-125b in the cholesteatoma and corresponding retroauricular skin. Immunohistochemical staining and western blot were used to detect signal transducers and activators of transcription 3 (STAT3) and the downstream gene cyclin D1, survivin, and vascular endothelial growth factor (VEGF) in the cholesteatoma and corresponding retroauricular skin. The targeted regulatory relationship between miR-125b and STAT3 was confirmed by dual luciferase reporter assay. Proliferation and apoptosis of transfected HaCaT cells were detected by MTS, cell cycle, and apoptosis assays.

Results

We observed down-regulation of miR-125b and up-regulation of STAT3, cyclin D1, survivin, and VEGF in cholesteatoma tissues. STAT3 was a direct target gene of miR-125b. Inhibition of miR-125b enhanced STAT3 and its downstream genes expression, promoted HaCaT cell proliferation, and inhibited apoptosis.

Conclusions

The results of this study demonstrate that miR-125b can influence the growth of cholesteatoma by targeting STAT3 and its downstream genes, including cyclin D1, survivin, and VEGF, thus providing an opportunity to establish new medical therapy strategies and facilitating further study of the pathogenesis of cholesteatoma.

Knockdown of serpin peptidase inhibitor clade C member 1 inhibits the growth of nasopharyngeal carcinoma cells

Nasopharyngeal carcinoma (NPC) is a type of cancer originating in the nasopharynx. There are no NPC‑specific treatments available at present. Serpin peptidase inhibitor clade C member 1 (SERPINC1) serves roles in anticoagulation and anti‑inflammation. The aim of the present study was to investigate the role of SERPINC1 in the proliferation and apoptosis of NPC cells. Tumor and adjacent healthy tissue samples were collected from patients with NPC. Additionally, the SERPINC1 gene was silenced in the HNE3 cell line using short interfering RNA targeted against SERPINC1 (SERPINC1‑siRNA). Cell viability was determined via a Cell Counting Kit‑8 assay; furthermore, proliferation and apoptosis were investigated via flow cytometry. Western blotting and reverse transcription‑quantitative polymerase chain reaction analysis were performed to determine the expression levels of protein and mRNA. It was revealed that the expression levels of SERPINC1 mRNA and protein were increased in NPC tumor tissues compared with in adjacent healthy tissues. The expression of SERPINC1 mRNA and protein in HNE3 cells decreased following SERPINC1‑siRNA transfection. Furthermore, knockdown of SERPINC1 promoted apoptosis and inhibited proliferation. It was also demonstrated that silencing SERPINC1 upregulated the expression of B‑cell lymphoma-2 (Bcl‑2)‑associated X protein and p53 mRNA and protein, and downregulated that of Bcl‑2, survivin and cyclin D1. Downregulation of SERPINC1 reduced the phosphorylation of phosphatidylinositol 3‑kinase (PI3K), protein kinase B (Akt) and mammalian target of rapamycin (mTOR). Thus, SERPINC1 knockdown may promote the apoptosis of HNE3 cells and inhibit proliferation via the suppression of the PI3K/Akt/mTOR signaling pathway.

[6]-Gingerol enhances the cisplatin sensitivity of gastric cancer cells through inhibition of proliferation and invasion via PI3K/AKT signaling pathway

Cisplatin-based chemotherapy is a widely used chemotherapeutic regimen for gastric cancer; however, drug resistance limits its efficacy. [6]-Gingerol has been found to exhibit anticancer effects. Here, we aim to explore the potential of [6]-gingerol in combination with cisplatin as a new regimen for gastric cancer. CCK-8 assay and colony formation assay were used to determine the effect of [6]-gingerol in combination with cisplatin on cell viability of gastric cancer cells. Flow cytometry was performed to assess cell cycle distribution. Wound-healing assay and transwell invasion assay were conducted to examine the migration and invasion abilities. Cell cycle and invasion-related proteins and mRNAs, as well as PI3K/AKT signaling proteins, were assessed by western blotting and quantitative real-time polymerase chain reaction. Combination of [6]-gingerol with cisplatin inhibited cell viability and enhanced cell cycle arrest at G1 phase compared with cisplatin alone. The combination treatment inhibited cell migration and invasion ability and decreased cyclin D1, cyclin A2, matrix metalloproteinase-9, p-PI3K, AKT, and p-AKT protein expressions and increased P21 and P27 mRNA levels. Our study demonstrates that [6]-gingerol enhances the cisplatin sensitivity of gastric cancer cells and that the mechanisms involve G1 phase arrest, migration and invasion suppression via PI3K/AKT signaling pathway.

Overexpression of miR-361-5p in triple-negative breast cancer (TNBC) inhibits migration and invasion by targeting RQCD1 and inhibiting the EGFR/PI3K/Akt pathway

Triple-negative breast cancer (TNBC) is the leading cause of cancer-related death in women. Previous studies indicated that miR-361-5p was downregulated in breast cancer, however, the exact effect of miR-361-5p on TNBC requires further investigation. In the present study, we investigated whether miR-361-5p can act as a tumor suppressor by targeting required for cell differentiation 1 homolog (RQCD1) and inhibiting epidermal growth factor receptor (EGFR)/phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) pathway in TNBC. The expression of miR-361-5p and RQCD1 was determined by quantitative reverse transcription PCR (qRT-PCR) and/or western blot in TNBC and the adjacent tissues. miR-361-5p mimics were constructed and transfected to TNBC cell line MDA-MB-231. Cells were divided into three groups: blank control group, miRNA mimic negative control (NC) group, and miR-361-5p mimics group. Expression of miR-361-5p, mRNA and protein expression of PI3K, Akt, EGFR, phosphorylated (p)-EGFR/PI3K/Akt, and protein expression of RQCD1 and matrix metallopeptidase 9 (MMP-9) in MDA-MB-231 were measured by qRT-PCR/western blot after transfection. Cell viability was determined by CCK-8 assay. Cell migration and invasion ability were evaluated by scratch and transwell assay, respectively. miR-361-5p target gene was determined by bioinformatics analysis and luciferase reporter assay. RQCD1 was identified as a target of miR-361-5p by TargetScan and confirmed by luciferase reporter assay. Downregulated miR-361-5p and upregulated RQCD1 were observed in TNBC tissues. Expression of EGFR, PI3K, Akt and MMP-9 was inhibited in cells treated with miR-361-5p mimics. Transfection of miR-361-5p mimics also inhibited the phosphorylation of EGFR, PI3K, and Akt. Suppressed cell viability, migration, and invasion was found in miR-361-5p mimics groups. Our results indicated that overexpression of miR-361-5p might act as a suppressor in TNBC by targeting RQCD1 to inhibit the EGFR/PI3K/Akt signaling pathway.

Y-box binding protein-1 promotes tumorigenesis and progression via the epidermal growth factor receptor/AKT pathway in spinal chordoma

Chordomas are rare bone tumors with a poor prognosis and no approved targeted therapy. Y‐box binding protein‐1 (YBX1) promotes tumor growth, invasion and drug resistance. However, the role of YBX1 in chordoma is unclear. In this study, we examined the expression of YBX1 using immunohistochemistry and found that YBX1 was significantly upregulated in 32 chordoma tissues compared to distant normal tissues. In addition, YBX1 upregulation was associated with surrounding tissue invasion, recurrence and poor prognosis. Biological function studies demonstrated that YBX1 promoted cell proliferation and invasion, accelerated G1/S phase transition, and inhibited apoptosis. Further investigation revealed that YBX1 enhanced epidermal growth factor receptor (EGFR) transcription by directly binding to its promoter in chordoma cells. YBX1 regulated protein expression of p‐EGFR, p‐AKT and its downstream target genes that influenced cell apoptosis, cell cycle transition and cell invasion. YBX1 activated the EGFR/AKT pathway in chordoma and YBX1‐induced elevated expression of key molecules in the EGFR/AKT pathway were downregulated by EGFR and AKT pathway inhibitors. These in vitro results were further confirmed by in vivo data. These data showed that YBX1 promoted tumorigenesis and progression in spinal chordoma via the EGFR/AKT pathway. YBX1 might serve as a prognostic and predictive biomarker, as well as a rational therapeutic target, for chordoma.

The prognostic value of S100A10 expression in cancer

S100A10, a member of the S100 protein family, commonly forms a heterotetrameric complex with Annexin A2. This is essential for the generation of cellular plasmin from plasminogen, which leads to a cascade of molecular events crucial for tumor progression. S100A10 upregulation has been reported in a number of cancers, suggesting that it may have potential as a prognostic biomarker, as well as predicting sensitivity to anticancer drugs. This review evaluates the direct and indirect relationships between S100A10 and cancer progression by investigating its role in cancer. Research papers published on PubMed and Google Scholar between 2007–2017 were collated and reviewed. We concluded that S100A10 affects the development of the hallmarks of cancer as explained by Hanahan and Weinberg in 2011, most notably by activating the invasion and metastasis of cancer cells. However, further studies are required to explore the underlying biological mechanisms of S100A10.

EPA significantly improves anti-EGFR targeted therapy by regulating miR-378 expression in colorectal cancer

It is known that colorectal cancer (CRC) cells containing mutations of the genes KRAS and BRAF are predominate mechanisms causing resistance to epidermal growth factor receptor (EGFR) inhibitors, and commonly exhibit a lower expression of microRNA-378 (miR-378) when compared with the wild type. In the present study, the aim was to determine the possible mechanism which associates miR-378 with the mitogen-activated protein kinase pathway, and to determine the efficiency of eicosapentaenoic acid ethyl ester (EPA) in its ability to restore sensitivity towards cetuximab, an EGFR inhibitor. The results demonstrated that a combined treatment of 40 µM EPA with 0.2 µM cetuximab can significantly suppress the cell growth in KRAS-mutant and control wild-type cells. Furthermore, the higher phosphorylated protein level of extracellular-signal-regulated kinase 1/2 was notable in KRAS EPA-treated cells (P=0.006-0.047) and resulted in significantly increased cell death; however, inconsistent results were indicated in EPA-treated BRAF-mutant cells, compared with the original cells (without treatment). KRAS-mutant and wild-type Caco-2 cells treated with EPA exhibited increased cetuximab response rates, but these response rates were reduced in the BRAF-mutant cells. In conclusion, upregulation of miR-378 induced by EPA may result in the significant restoration of sensitivity to cetuximab in the KRAS-mutant cells. The present data will contribute to a notable potential therapeutic solution for future clinical CRC treatments.

LncRNA ABHD11-AS1 promotes the development of endometrial carcinoma by targeting cyclin D1

To investigate the expression, role and mechanism of action of long non-coding RNA (lncRNA) ABHD11-AS1 in endometrial carcinoma. The expression of lncRNA ABHD11-AS1 was quantified by qRT-PCR in human endometrial carcinoma (n = 89) and normal endometrial tissues (n = 27). LncRNA ABHD11-AS1 was stably overexpressed or knocked-down in endometrial carcinoma cell lines to examine the cellular phenotype and expression of related molecules. Compared to normal endometrial tissue, lncRNA ABHD11-AS1 was significantly overexpressed in endometrial carcinoma. Overexpression of lncRNA ABHD11-AS1 promoted the proliferation, G1-S progression, invasion and migration of endometrial cancer cells; inhibited apoptosis; up-regulated cyclin D1, CDK1, CDK2, CDK4, Bcl-xl and VEGFA; and down-regulated p16, while ABHD11-AS1 down-regulation has the opposite effect. RNA pull down demonstrated that lncRNA ABHD11-AS1 binds directly to cyclin D1. Knockdown of cyclin D1 can reverse the effect of ABHD11-AS1. Overexpression of lncRNA ABHD11-AS1 increased the tumorigenicity and up-regulated cyclin D1 in an in vivo model of endometrial cancer in nude mice. LncRNA ABHD11-AS1 functions as an oncogene to promote cell proliferation and invasion in endometrial carcinoma by positively targeting cyclin D1.

Long noncoding RNAs show differential expression profiles and display ceRNA potential in cholesteatoma pathogenesis

Cholesteatoma is a pathologically benign but clinically destructive middle ear disease, which is caused by excessive epidermal migration and uncontrolled hyperproliferation of keratinocytes of squamous epithelium, leading to various clinical manifestations and serious complications, such as hearing loss, dizziness, facial paralysis, meningitis, and hydrocephalus. However, the pathogenesis of cholesteatoma is still not fully understood. Herein, we performed microarray analysis to identify the differentially expressed patterns of lncRNAs in cholesteatoma for the first time. Our data indicated that compared with matched normal skin tissue, lncRNA expression profiles were significantly altered in cholesteatoma. A total of 787 lncRNAs were identified (fold change ≥2.0, P<0.05), consisting of 181 upregulated and 606 downregulated lncRNAs. Furthermore, by constructing an lncRNA/miRNA/mRNA competing endogenous RNA (ceRNA) network, we found that lncRNAs, such as lncRNA‑uc001kfc.1, had ceRNA potential in cholesteatoma formation. In conclusion, lncRNAs were aberrantly expressed in cholesteatoma compared with normal skin tissues and may play important roles in cholesteatoma formation. Our findings shed novel light on the molecular mechanism of cholesteatoma pathogenesis and suggest that lncRNAs may be potential therapeutic targets for cholesteatoma.

Mometasone furoate inhibits growth of acute leukemia cells in childhood by regulating PI3K signaling pathway

OBJECTIVES

Acute lymphoblastic leukemia (ALL) is the most common cancer before the age of 15 years, seriously endangering the health of children. The main treatment for Childhood ALL was pharmacotherapy. But these drugs have many side effects and some of them could develop drug resistance quickly. Mometasone furoate (MF) is an efficient glucocorticoid for topical treatment of inflammation on the skin, lung and nose.

METHODS

In this study, we investigated whether the MF had effects on ALL cells proliferation and migration.

RESULTS

The CCK-8 proliferation test showed that the cell viability was the lowest at 25 nM MF treatment and the increased OD value was time-dependent. In transwell assay, the number of CCRF-CEM cells was reduced in MF treated group. We found the expression of anti-apoptotic protein bcl-2 decreased the expression of pro-apoptotic protein caspase3 and bax increased in CCRF-CEM cell line treated with MF. The expression of p-AKT, p-mTOR, p70S6 K, vascular endothelial growth factor and CyclinD1 were decreased in MF treated group.

CONCLUSION

This study reveals that MF can inhibit proliferation and invasion/migration and induce apoptosis in Childhood ALL cells, which may be regulated by Phosphatidylinositol 3-kinase signaling pathway. These results suggest MF may be a potential new drug target for clinical ALL treatment.

Telmisartan inhibits NSCLC A549 cell proliferation and migration by regulating the PI3K/AKT signaling pathway

Expression of angiotensin II (Ang II), a key biological peptide in the renin-angiotensin system, is closely associated with the occurrence and development of cancer. Ang II binds two receptor subtypes, the Ang II type 1 receptor (AT1R) and the AT2R, to mediate a series of biological effects. Telmisartan, a specific AT1R blocker, has been reported to have potential as an anticancer drug for treating renal cancer. In the present study, whether telmisartan had an effect on non-small cell lung cancer (NSCLC) cell proliferation and migration was investigated. The Cell Counting kit-8 assay revealed that telmisartan significantly inhibited the growth of the NSCLC A549 cell line in a time- and dose-dependent manner. In a transwell assay, telmisartan significantly inhibited cellular invasion and migration. Furthermore, it was determined that the expression of the anti-apoptotic protein B-cell lymphoma was decreased, and that of the pro-apoptotic proteins caspase-3 and Bcl-associated X increased in the A549 cells treated with telmisartan. Additionally, levels of phosphorylated RAC serine/threonine-protein kinase (p-AKT), p-mechanistic target of rapamycin, p70-S6 kinase and cyclin D1 was decreased in the telmisartan-treated group. Therefore, the current study reveals that telmisartan-induced NSCLC apoptosis may be regulated via the phosphoinositide 3-kinase/AKT signaling pathway, which indicates that it may be a potential novel drug for clinical NSCLC treatment.

Stimulatory effect of icariin on the proliferation of neural stem cells from rat hippocampus

Background

Icariin (ICA), a major ingredient of Epimediumbrevicornum, has various pharmacological activities including central nervous system protective functions such as the improvement of learning and memory function in mice models of Alzheimer’s disease. It has been reported that ICA can promote regeneration of peripheral nerve and functional recovery. The purpose of this study was to investigate the potentiating effect of ICA on the proliferation of rat hippocampal neural stem cells, and explore the possible mechanism involved.

Methods

Primary neural stem cells were prepared from the hippocampus of newly born SD rats, and cells were cultured in special stem cell culture medium. Neural stem cells were confirmed by immunofluorescence detection of nestin, NSE and GFAP expression. The effect of ICA on the growth and proliferation of the neural stem cells was evaluated by 5-ethynyl-2-deoxyuridine (EdU) labeling of proliferating cells, and photomicrographic images of the cultured neural stem cells. Further, the mechanism of ICA-induced cell proliferation of neural stem cells was investigated by analyzing the gene and protein expression of cell cycle related genes cyclin D1 and p21.

Results

The present study showed that icariin promotes the growth and proliferation of neural stem cells from rat hippocampus in a dose-dependent manner. Incubation of cells with icariin resulted in significant increase in the number of stem cell spheres as well as the increased incorporation of EdU when compared with cells exposed to control vehicle. In addition, it was found that icariin-induced effect on neural stem cells is associated with increased mRNA and protein expression of cell cycle genes cyclin D1 and p21.

Conclusions

This study evidently demonstrates the potentiating effect of ICA on neural stem cell growth and proliferation, which might be mediated through regulation of cell cycle gene and protein expression promoting cell cycle progression.

Electronic supplementary material

The online version of this article (10.1186/s12906-018-2095-y) contains supplementary material, which is available to authorized users.

Microarray Analysis of Differentially-expressed MicroRNAs in Acquired Middle Ear Cholesteatoma

Objectives: To analyze the miRNAs expression profiling between acquired middle ear cholesteatoma and normal skin, and to identify several novel miRNAs which may be involved in the etiopathogenesis of middle ear cholesteatoma. Methods: MiRNA microarray technology was adopted to analyze the miRNA expression profiling between acquired middle ear cholesteatoma and normal skin. qRT-PCR was used to validate selected differentially expressed miRNAs. Results: The miRNA microarray technology showed totally 44 upregulated (miRNA-21-3p, miRNA-584-5p, miRNA-16-1-3p, etc) and 175 downregulated (miRNA-10a-5p, miRNA-152-5p, miRNA-203b-5p, etc) miRNAs in cholesteatoma tissues with 2-fold change compared with normal skin. The qRT-PCR validation was in accordance with the microarray results partly: miRNA-21-3p and miRNA-16-1-3p expressed significantly higher while miRNA-10a-5p exhibited an obviously decreased expression in middle ear cholesteatoma tissues when compared with normal skin. The GO and KEGG pathway analyses provided clues that these differentially expressed miRNAs might play essential roles in the etiopathogenesis of middle ear cholesteatoma, including cell proliferation, apoptosis, cell cycle, differentiation, bone resorption and remodeling process. Conclusions: Our study suggests possible roles of differentially expressed miRNAs in the pathogenesis of middle ear cholesteatoma. Targeting on these miRNAs may provide a new strategy for cholesteatoma therapy in the future.

SALL4 suppresses PTEN expression to promote glioma cell proliferation via PI3K/AKT signaling pathway

Spalt-like transcription factor 4 (SALL4), a oncogene, is known to participate in multiple carcinomas, and is up-regulated in glioma. However, its actual role and underlying mechanisms in the development of glioma remain unclear. The present study explored the molecular functions of SALL4 in promoting cell proliferation in glioma. The expression level of SALL4 in 69 human glioma samples and six non-tumor brain tissues was determined using real-time polymerase chain reaction (PCR). Then, we transfected U87 and U251 cell lines with siRNA, and assessed cellular proliferation and cell cycle to understand the function of SALL4, and the relationship between SALL4, PTEN and PI3K/AKT pathway. PCR confirmed that the expression of SALL4 was higher in the glioma samples than non-tumor brain tissues. Cellular growth and proliferation were dramatically reduced following inhibition of SALL4 expression. Western blot showed increase in PTEN expression when SALL4 was silenced, which in turn depressed the activation of PI3K/AKT pathway, suggesting that PTEN was a downstream target of SALL4 in glioma development. Therefore, SALL4 could act as a proto-oncogene by regulating the PTEN/PI3K/AKT signaling pathway, thereby facilitating proliferation of glioma cells.

HB-EGF expression as a potential biomarker of acquired middle ear cholesteatoma

CONCLUSIONS

The heparin-binding epidermal growth factor-like growth factor (HB-EGF) plays an essential role in the development and invasiveness of cholesteatoma. This study may help to realize the molecular mechanisms underlying the pathogenesis of cholesteatoma and make HB-EGF a promising target for drug intervention of cholesteatoma.

OBJECTIVE

To detect HB-EGF expression in human surgical specimens of acquired middle ear cholesteatoma and analyze its functional role as a regulator of epithelial keratinocytes hyperproliferation.

METHODS

A total of 34 patients who underwent surgical treatment for middle ear cholesteatoma were recruited in the study. The mRNA and protein expression of HB-EGF in middle ear cholesteatoma tissues and normal postauricular skin tissues was investigated by real-time quantitative reverse-transcription-polymerase chain reaction (RT-qPCR), immunohistochemical staining, and western blot. The correlation between bone resorption degree and HB-EGF expression was also analyzed.

RESULTS

On average, compared with normal postauricular skin, expression of HB-EGF mRNA in the cholesteatoma epithelium was significantly elevated 2.41-fold by RT-qPCR, and HB-EGF protein significantly upregulated 2.32-fold by western blot. Positive HB-EGF immunostaining observed in the basal and suprabasal layers of cholesteatoma epithelium was significantly stronger than in normal postauricular skin. Meanwhile, an obviously positive correlation between HB-EGF protein expression and bone resorption degree was discovered.

Redox Imbalance in the Development of Colorectal Cancer

Redox imbalance is resulted from the destruction of balance between oxidants and antioxidants. The dominant oxidants are reactive oxygen species (ROS), which are involved in multiple cellular processes by physiologically transporting signal as a second messenger or pathologically oxidizing DNA, lipids, and proteins. Generally speaking, low concentration of ROS is indispensable for cell survival and proliferation. However, high concentration of ROS is cytotoxic. Additionally, ROS are now known to induce the oxidative modification of macromolecules especially proteins. The redox modification of proteins is involved in numerous biological processes related to diseases including CRC. Herein, we attempt to afford an overview that highlights the crosstalk between redox imbalance and CRC.

The Role of Rho/Rho-Kinase Pathway in the Pathogenesis of Cholesteatoma

OBJECTIVE

To assess the role of Rho/Rho-kinase pathway in the pathogenesis of cholesteatoma.

MATERIALS AND METHODS

Thirty-eight patients with cholesteatoma, who had gone mastoidectomies were enrolled in this prospective study. Cholesteatomas matrix (CM) and a piece of the external ear canal skin (EECS as control) were taken and transferred to the liquid nitrogen and kept at -86 °C for Rho A and Rho-kinase (ROCK) analysis with Western blotting and commercial ELISA kits (Cell Biolabs Inc., San Diego, CA). The tissues were homogenized by an appropriate ice-cold lysis buffer. Following centrifugation, the supernatant was taken and total protein amount was detected by the Bradford method. Thereafter, tissue homogenates were subjected to sodium dodecyl sulphate (SDS)-polyacrylamide gel electrophoresis electrophoresis then transferred to nitrocellulose membrane where it was treated with specific monoclonal primary antibody against to ROCK-2 and HRP-conjugated seconder antibody, respectively. The protein blots were visualized with commercial x-ray film and dansitometrically analyzed by the Scion Image Program (Cell Biolabs Inc., San Diego, CA). In another series of experiments, Rho-kinase activities were assessed by ROCK-2 ELISA kits.

RESULTS

There were no statistical differences in Rho A translocation between CM and EECS. However, ROCK activity was found to be lower in CM than EECS as detected by ELISA kits. Furthermore, ROCK protein expression was also significantly lower in CM than EECS as demonstrated by Western blotting.

CONCLUSION

Given Rho-kinase could take essential roles in cell differentiation, the results of this study implicate that down-regulated Rho-kinase could be responsible for the keratinocyte undifferentiation seen in cholesteatoma pathogenesis.

Epidermal Growth Factor Induces Proliferation of Hair Follicle-Derived Mesenchymal Stem Cells Through Epidermal Growth Factor Receptor-Mediated Activation of ERK and AKT Signaling Pathways Associated with Upregulation of Cyclin D1 and Downregulation of p16

The maintenance of highly proliferative capacity and full differentiation potential is a necessary step in the initiation of stem cell-based regenerative medicine. Our recent study showed that epidermal growth factor (EGF) significantly enhanced hair follicle-derived mesenchymal stem cell (HF-MSC) proliferation while maintaining the multilineage differentiation potentials. However, the underlying mechanism remains unclear. Herein, we investigated the role of EGF in HF-MSC proliferation. HF-MSCs were isolated and cultured with or without EGF. Immunofluorescence staining, flow cytometry, cytochemistry, and western blotting were used to assess proliferation, cell signaling pathways related to the EGF receptor (EGFR), and cell cycle progression. HF-MSCs exhibited surface markers of mesenchymal stem cells and displayed trilineage differentiation potentials toward adipocytes, chondrocytes, and osteoblasts. EGF significantly increased HF-MSC proliferation as well as EGFR, ERK1/2, and AKT phosphorylation (p-EGFR, p-ERK1/2, and p-AKT) in a time- and dose-dependent manner, but not STAT3 phosphorylation. EGFR inhibitor (AG1478), PI3K-AKT inhibitor (LY294002), ERK inhibitor (U0126), and STAT3 inhibitor (STA-21) significantly blocked EGF-induced HF-MSC proliferation. Moreover, AG1478, LY294002, and U0126 significantly decreased p-EGFR, p-AKT, and p-ERK1/2 expression. EGF shifted HF-MSCs at the G1 phase to the S and G2 phase. Concomitantly, cyclinD1, phosphorylated Rb, and E2F1expression increased, while that of p16 decreased. In conclusion, EGF induces HF-MSC proliferation through the EGFR/ERK and AKT pathways, but not through STAT-3. The G1/S transition was stimulated by upregulation of cyclinD1 and inhibition of p16 expression.

MicroRNA let-7a suppresses the growth and invasion of cholesteatoma keratinocytes

Cholesteatomas are benign epidermally‑derived lesions of the temporal bone that are caused by migration of hyperproliferative keratinocytes into the middle ear and mastoid cavity. The molecular mechanisms that regulate the pathogenesis of cholesteatomas are currently not fully understood. The present study demonstrated the antigrowth and anti‑invasive effects of let‑7a microRNA (miRNA) on cholesteatoma keratinocytes. Let‑7a inhibited the growth of cholesteatoma keratinocytes through two different mechanisms: Restriction of the proliferation of keratinocytes by promoting cell cycle arrest in the G0/G1 phase, and the induction of apoptosis of the cells. In addition to its role in the inhibition of cell growth, let‑7a suppressed the migration and invasion of cholesteatoma keratinocytes. A mechanistic study showed that let‑7a downregulated the expression of miR‑21. Considering the function of miR‑21 in the regulation of proliferation and apoptosis, let‑7a may control cell proliferation and apoptosis by regulating miR‑21, and its targets, in cholesteatoma keratinocytes. In conclusion, the present study showed that let‑7a downregulates the expression of miR‑21, resulting in the suppression of proliferation and induction of apoptosis. The results of the present study reveal the crucial role of let‑7a miRNA in the inhibition of growth and invasion of cholesteatoma keratinocytes.

Chronopharmacology and mechanism of antitumor effect of erlotinib in Lewis tumor-bearing mice

The epidermal growth factor receptor (EGFR), a ubiquitously expressed receptor tyrosine kinase, is recognized as a key mediator of tumorigenesis in many human epithelial tumors. Erlotinib is tyrosine kinase inhibitor approved by FDA for use in oncology. It inhibits the intracellular phosphorylation of tyrosine kinase associated with the EGFR to restrain the development of the tumor. To investigate the antitumor effect of erlotinib at different dosing times and the underlying molecular mechanism via the PI3K/AKT pathway, we established a mouse model of Lewis lung cancer xenografts. The tumor-bearing mice were housed four or five per cage under standardized light-dark cycle conditions (light on at 7:00 AM, 500 Lux, off at 7:00 PM, 0 Lux) with food and water provided ad libitum. The mice were observed for quality of life, their body weight and tumor volume measured, and the tumor growth curves drawn. After being bled, the mice were sacrificed by cervical dislocation. The tumor masses were removed at different time points and weighed. The mRNA expression of EGFR, AKT, Cyclin D1 and CDK-4 were assayed by quantitative real-time PCR (qRT-PCR). Protein expression levels of AKT, P-AKT and Cyclin D1 were determined by Western blot analysis. The results suggest that erlotinib has a significant antitumor effect on xenografts of non-small cell lung cancer in mice, and its efficacy and toxicity is dependent on the time of day of administration. Its molecular mechanism of action might be related to the EGFR-AKT-Cyclin D1-CDK-4 pathway which plays a crucial role in the development of pathology. Therefore, our findings suggest that the time of day of administration of Erlotinib may be a clinically important variable.