Cancer Stem Cells and Epithelial-to-Mesenchymal Transition (EMT)-Phenotypic Cells: Are They Cousins or Twins?

Curcumin Derivative C086 Combined with Cisplatin Inhibits Proliferation of Osteosarcoma Cells

Background

Curcumin derivative C086 (cur C086) is a potential chemotherapeutic agent for patients with osteosarcoma. In this study, the effects of cur C086 combined with cisplatin on the biological processes of osteosarcoma cells were investigated.

Material/Methods

In this study, expression of BMIL1 was detected by real-time quantitative reverse transcription polymerase chain reaction and Western blotting in MG-63 cells treated with cur C086+cisplatin. Functions of cur C086+cisplatin on proliferation ability, apoptosis response, and metastatic potential of MG-63 cells were determined by MTT, flow cytometry, Hoechst 33258 staining and Transwell assays, respectively. In additionally, expression of P16, E-cadherin, epidermal growth factor (EGFR), and Notch1 was measured by Western blotting.

Results

Expression of BMIL1 decreased significantly in MG-63 cells treated with cur C086 (20 μM)+cisplatin (1.28 nM). Treatment with cur C086+cisplatin considerably inhibited growth, migration, and invasion potential in MG-63 cells, whereas apoptosis was obviously upregulated. Moreover, cur C086+cisplatin suppressed BMIL1 expression or its potential downstream targets, P16, E-cadherin, EGFR, and Notch1.

Conclusions

The current results demonstrate that combined treatment with cur C086+cisplatin may be an effective form of chemotherapy for patients with osteosarcoma.

MicroRNA‑590 inhibits migration, invasion and epithelial‑to‑mesenchymal transition of esophageal squamous cell carcinoma by targeting low‑density lipoprotein receptor‑related protein 6

MicroRNA-590 (miR-590) has been revealed as a tumor suppressor, while low-density lipoprotein receptor-related protein 6 (LRP6) is considered to act as a tumor promoter. However, their roles and underlying molecular regulatory mechanisms in esophageal squamous cell carcinoma (ESCC) have yet to be fully elucidated. Therefore, the present study aimed to investigate these mechanisms. The expression levels of miR-590 and LRP6 in human ESCC samples and cell lines were determined using reverse transcription-quantitative PCR. Bioinformatics analysis was used to predict the relationship between miR-590 and LRP6, and luciferase assay was performed to validate the relationship between these factors. Transwell assays were used to determine cell migration and invasion, while western blotting assays were used to detect the protein expression levels of LRP6, E-cadherin, N-cadherin and Vimentin. The present study demonstrated that miR-590 was downregulated and LRP6 was upregulated in ESCC tissues and cell lines. Furthermore, it was found that miR-590 overexpression and LRP6 knockdown inhibited cell migration, invasion and epithelial-to-mesenchymal transition (EMT) in ESCC cell lines. Additional mechanistic studies identified that LRP6 was a target of, and was inhibited by, miR-590. Collectively, the present findings suggested that miR-590 inhibited the invasion, migration and EMT of ESCC cells by mediating LRP6.

Alpha-1 Antitrypsin Induces Epithelial-to-Mesenchymal Transition, Endothelial-to-Mesenchymal Transition, and Drug Resistance in Lung Cancer Cells

Purpose

Alpha-1 antitrypsin (A1AT) is a secreted protein that plays an important role in various diseases. However, the role of A1AT in non-small cell lung cancer is obscure.

Materials and Methods

A1AT expression in non-small cell lung cancer was analyzed using quantitative reverse transcription PCR, Western blotting (WB), immunohistochemistry (IHC), and ELISA. WB and IF were used to analyze markers of epithelial-to-mesenchymal transition (EMT), EndoMT, and cancer stem cell (CSC). Transwell and cell wound healing assays were used to analyze migration and invasion abilities. Colony formation and CCK-8 assays were used to analyze cell proliferation following cisplatin treatment.

Results

A1AT expression was higher in lung cancer samples than in normal tissues and the increased expression was correlated with poor overall survival of patients. In vitro experiments showed that A1AT overexpressed by plasmid transfection significantly promoted migration, invasion, EMT, EndoMT, stemness, and colony formation in lung cancer cell lines, as opposed to A1AT downregulation by siRNA transfection, which significantly inhibited all these variables.

Conclusion

A1AT is a novel therapeutic target and might be associated with tumor metastasis in lung carcinoma.

Recent Trends of microRNA Significance in Pediatric Population Glioblastoma and Current Knowledge of Micro RNA Function in Glioblastoma Multiforme

Central nervous system tumors are a significant problem for modern medicine because of their location. The explanation of the importance of microRNA (miRNA) in the development of cancerous changes plays an important role in this respect. The first papers describing the presence of miRNA were published in the 1990s. The role of miRNA has been pointed out in many medical conditions such as kidney disease, diabetes, neurodegenerative disorder, arthritis and cancer. There are several miRNAs responsible for invasiveness, apoptosis, resistance to treatment, angiogenesis, proliferation and immunology, and many others. The research conducted in recent years analyzing this group of tumors has shown the important role of miRNA in the course of gliomagenesis. These particles seem to participate in many stages of the development of cancer processes, such as proliferation, angiogenesis, regulation of apoptosis or cell resistance to cytostatics.

Expression of E-cadherin, Ki-67, and p53 in urinary bladder cancer in relation to progression, survival, and recurrence

Although the incidence varies with age and gender, urothelial bladder cancer is a relatively frequently occurring malignancy with variable clinical behavior that often has high recurrence rates. In this study, we analyzed the tumor tissues of 224 patients with pTa, pT1, and pT2 urinary bladder cancer. We performed a histomorphologic analysis and immunohistochemistry for p53, Ki-67, and E-cadherin, which were selected as markers of the malignant process. For pTa and pT1, univariate analyses of cancer-specific survival (CSS), progression-free survival (PFS), and recurrence-free survival (RFS) were calculated using the Kaplan-Meier method, the log-rank test and Cox regression. Multivariate analysis was performed by a Cox regression analysis. Ki-67 (P<0.001) was significantly associated with CSS, but the highest association was shown for E-cadherin (P<0.001). For pT1 and pTa, the Kaplan-Meier analysis and the log-rank test revealed significantly worse PFS for patients with higher levels of Ki-67 (P<0.001) and lower levels of E-cadherin (P<0.001). Based on these obtained results, it can be clearly stated that Ki-67 and E-cadherin expression levels are associated with CSS, PFS and RFS. The clinical utility of these markers is valuable for pTa and pT1 urinary bladder cancer and should be further verified with prospective multi-center trials.

PRDX4 overexpression is associated with poor prognosis in gastric cancer

Peroxiredoxin IV (PRDX4) is a multifunctional protein that is involved in cell protection against oxidative injury, regulation of cell proliferation, modulation of intracellular signaling, and the pathogenesis of tumors. We previously conducted a proteomic analysis to investigate tumor-specific protein expression in gastric cancer. The aim of the present study was to investigate whether PRDX4 could be a marker of poor prognosis in patients with gastric cancer. Immunohistochemistry was used to validate PRDX4 as a prognostic marker for gastric cancer. Short hairpin RNA (shRNA)-mediated knockdown of PRDX4 expression in AGS cells and MKN28 cells was used for functional studies, and PRDX4 overexpression in PRDX4-depleted cells was used for knock-in studies. Based on immunohistochemistry data, TNM stage and PRDX4 were independent prognostic factors in the Cox proportional hazard model (P<0.05). In the survival analysis, the PRDX4-overexpressing group demonstrated significantly worse survival than the PRDX4-underexpression group (P<0.01). In vitro, knockdown of PRDX4 expression by shRNA caused a significant decrease in cancer invasion. Conversely, overexpression of PRDX4 in PRDX4-depleted cancer cells promoted migration and invasion. By measuring the expression of EMT-related genes, we found that E-cadherin was increased in shPRDX4 cells compared with control shMKN28 cells, and snail and slug were decreased in shPRDX4-1 cells compared with sh-control cells. Furthermore, the expression levels of these genes could be recovered in rescue experiments. In conclusion, the results of the present study suggested that PRDX4 is a marker of poor prognosis in gastric cancer and that PRDX4 is associated with cancer cell migration and invasion via EMT.

CD44+CD24-/low sphere-forming cells of EBV-associated gastric carcinomas show immunosuppressive effects and induce Tregs partially through production of PGE2

EBV-associated gastric carcinoma (EBVaGC) is accompanied by massive lymphocyte infiltration, but therapy resistance and tumor progression still occur in patients with EBVaGC. Cancer stem cells (CSCs) are reported to possess immunomodulatory ability that allows them to resist immune-mediated rejection for many tumor types. However, whether and how CSCs in EBVaGC exhibit immunosuppression has not yet been elucidated. We isolated CSC-like sphere-forming cells (SFCs) from EBVaGC cell line SNU-719 using the cancer sphere method. We validated their CSC-associated properties in the expression of the epithelial-mesenchymal transition (EMT)-related genes, the ability to form colonies, and resistance to chemotherapy drug-induced apoptosis and explored their immunomodulatory ability using the coculture system with PBMC (peripheral blood mononuclear cell). These CSC-like SFCs were CD44⁺CD24^-/low and were more tumorigenic than the parental SNU-719 cells in the xenograft mouse model. Remarkably, in the tumor-PBMC co-culturing experiments, these EBVaGC SFCs demonstrated profound immunosuppression by inhibiting the proliferation of PBMCs and T cell activation as well as inducing the generation of regulatory T cells (Tregs). Furthermore, the induction of Tregs was partially dependent on prostaglandin E2 (PGE2) produced from SFCs. Moreover, the presence of high CD44⁺CD24^-/low cells in tumor tissues predicted a decreased disease-free survival in patients with EBVaGC. Our study collectively confirmed the existence and immune resistance of CSCs in EBVaGC and offers new insights into the development of novel anti-EBVaGC strategies by targeting CSCs.

Tumor Cell Invasion in Glioblastoma

Glioblastoma (GBM) is a particularly devastating tumor with a median survival of about 16 months. Recent research has revealed novel insights into the outstanding heterogeneity of this type of brain cancer. However, all GBM subtypes share the hallmark feature of aggressive invasion into the surrounding tissue. Invasive glioblastoma cells escape surgery and focal therapies and thus represent a major obstacle for curative therapy. This review aims to provide a comprehensive understanding of glioma invasion mechanisms with respect to tumor-cell-intrinsic properties as well as cues provided by the microenvironment. We discuss genetic programs that may influence the dissemination and plasticity of GBM cells as well as their different invasion patterns. We also review how tumor cells shape their microenvironment and how, vice versa, components of the extracellular matrix and factors from non-neoplastic cells influence tumor cell motility. We further discuss different research platforms for modeling invasion. Finally, we highlight the importance of accounting for the complex interplay between tumor cell invasion and treatment resistance in glioblastoma when considering new therapeutic approaches.

Oxymatrine reverses 5-fluorouracil resistance by inhibition of colon cancer cell epithelial-mesenchymal transition and NF-κB signaling in vitro

The present study investigated the sensitization of 5-fluorouracil (5-FU)-resistant colon cancer cells in vitro, using oxymatrine, a Chinese herb, and a quinolizidine alkaloid compound extracted from the root of Sophora flavescens. The HCT-8 colon cancer cell line and its 5-FU-resistant subline HCT-8/5-FU were treated with 5-FU and oxymatrine, alone or in combination, at various doses. The cells were subsequently assessed for changes in cell viability, apoptosis and morphology and analyzed by fluorescence microscopy and western blotting. The data demonstrated that HCT-8/5-FU markedly increased the dose of 5-FU required for the suppression of tumor cell viability (78.77±1.90 µg/ml vs. 9.20±0.96 µg/ml in parental HCT-8 cells), whereas HCT-8/5-FU induced the tumor cell epithelial-mesenchymal transition (EMT). By contrast, oxymatrine alone and in combination with 5-FU altered HCT-8/5-FU cell morphology, apoptosis and EMT phenotypes. The combination of oxymatrine and 5-FU reduced the protein expression of snail family transcriptional repressor 2 and vimentin, phosphorylated p65 and induced the expression of E-cadherin, by inhibiting the nuclear factor κB (NF-κB) signaling pathway. In conclusion, the data from the present study demonstrated that EMT was associated with 5-FU chemoresistance in HCT-8/5-FU colon cancer cells, and that oxymatrine treatment was able to reverse such resistance. Oxymatrine may regulate tumor cell EMT and inactivate the NF-κB signaling pathway, and may therefore serve as a potential therapeutic drug to reverse 5-FU resistance in colon cancer cells.

miR-194 suppresses epithelial-mesenchymal transition of retinal pigment epithelial cells by directly targeting ZEB1

Background

Epithelial-mesenchymal transition (EMT) of the retinal pigment epithelial (RPE) cells is a critical step in the pathogenesis of proliferative vitreoretinopathy (PVR). Some microRNAs (miRNAs) participate in regulating RPE cell EMT as post-transcriptional regulators. However, the function of miR-194 in RPE cell EMT remains elusive. Here, the role of miR-194 in PVR was investigated.

Methods

Retinal layers were obtained using laser capture microdissection (LCM). Gene expression at the mRNA and protein level in the tissues and cells was examined using quantitative reverse transcription (RT)-polymerase chain reaction and Western blotting, respectively. The related protein expression was observed by immunostaining. The effect of miR-194 on RPE cell EMT was examined by gel contraction, wound healing, and cell migration assays. RNAseq was performed in ARPE-19 with transfection of pSuper-scramble and pSuper-miR-194. The target gene of miR-194 was identified and confirmed via bioinformatics analysis and dual-luciferase reporter assay. ARPE-19 (adult retinal pigment epithelium-19) cells were treated with transforming growth factor (TGF)-β1 in the same fashion as the in vitro RPE cell EMT model. A PVR rat model was prepared by intravitreous injection of ARPE-19 cells with plasma-rich platelets.

Results

miR-194 was preferentially expressed in the RPE cell layer compared with the outer nuclear layer (ONL), inner nuclear layer (INL), and ganglion cell layer in rat retina. RNAseq analysis indicated that miR-194 overexpression was involved in RPE cell processes, including phagocytosis, ECM-receptor interaction, cell adhesion molecules, and focal adhesion. miR-194 overexpression significantly inhibited the TGF-β1-induced EMT phenotype of RPE cells in vitro. Zinc finger E-box binding homeobox 1 (ZEB1), a key transcription factor in EMT, was confirmed as the direct functional target of miR-194. Knockdown of ZEB1 attenuated TGF-β1-induced α-smooth muscle actin expression in ARPE-19 cells, and overexpression of miR-194 could significantly reduce the expression of some genes which were up-regulated by ZEB1. Exogenous miR-194 administration in vivo effectively suppressed PVR in the rat model, both functionally and structurally.

Conclusions

Our findings demonstrate for the first time that miR-194 suppresses RPE cell EMT by functionally targeting ZEB1. The clinical application of miR-194 in patients with PVR merits further investigation.

CD133: An emerging prognostic factor and therapeutic target in colorectal cancer

Colorectal cancer (CRC) is one of the leading causes of death worldwide. Recently, the role of cancer stem cells (CSCs) has been highlighted as a crucial emerging factor in chemoresistance, cancer relapse, and metastasis. CD133 is a surface marker of CSCs and has been argued to have prognostic and therapeutic values in CRC along with its related pathways such as Wnt, Notch, and hedgehog. Several studies have successfully applied targeted therapies against CD133 in CRC models namely bispecific antibodies (BiAbs) and anti-Wnt and notch pathways agents. These studies have yielded initial promising results in this regard. However, none of the therapeutics have been used in the clinical setting and their efficacy and adverse effects profile are yet to be elucidated. This review aims to gather the old and most recent data on the prognostic and therapeutic values of CD133 and CD133-targeted therapies in CRC.

Expression Of BMP7 In Ovarian Cancer And Biological Effect Of BMP7 Knockdown On Ovarian Cancer Cells

Purpose

The aim of our research was to investigate the expression of BMP7 in ovarian cancer (OC) and the biological effect of knocking down BMP7 on ovarian cancer A2780 cells.

Methods

We detected BMP7 expression in ovarian cancer and normal ovarian tissue by immunohistochemistry (IHC). We downregulated BMP7 expression using lentivirus-mediated RNAi and then examined the effects of knocking down BMP7 on the cell growth and invasion, cell cycle and paclitaxel sensitivity of A2780 cells. The mRNA and protein levels were detected by total RNA extraction and quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting, respectively. Cell proliferation was measured by CCK-8 and colony formation assays. The number of cells in each cell cycle stage and those undergoing apoptosis were measured by flow cytometry.

Results

BMP7 expression was significantly higher in the ovarian cancer tissues than it was in the normal ovarian tissues. Knocking down BMP7 in ovarian cancer A2780 cells inhibited cell proliferation, migration and invasion; led to G1 cell cycle arrest; and reversed the epithelial-mesenchymal transformation (EMT) process. In addition, downregulating BMP7 increased the sensitivity of the A2780 cells to paclitaxel. Moreover, BMP7 downregulation resulted in decreased expression of Smad1/5/9, p-Smad1/5/9, ID2 and cyclin D1 protein.

Conclusion

The results presented here are expected to contribute to the development of possible therapeutic targets for patients with ovarian cancer.

The effects of growth hormone on therapy resistance in cancer

Pituitary derived and peripherally produced growth hormone (GH) is a crucial mediator of longitudinal growth, organ development, metabolic regulation with tissue specific, sex specific, and age-dependent effects. GH and its cognate receptor (GHR) are expressed in several forms of cancer and have been validated as an anti-cancer target through a large body of in vitro, in vivo and epidemiological analyses. However, the underlying molecular mechanisms of GH action in cancer prognosis and therapeutic response had been sparse until recently. This review assimilates the critical details of GH-GHR mediated therapy resistance across different cancer types, distilling the therapeutic implications based on our current understanding of these effects.

TNNT1, a prognostic indicator in colon adenocarcinoma, regulates cell behaviors and mediates EMT process

Slow skeletal muscle troponin T (TNNT1) has been reported to be correlated with several cancers, but there are no evidences proving that TNNT1 is required in colon adenocarcinoma (COAD). TNNT1 expression in COAD tissues and its prognostic significance were acquired from TCGA database. The proliferative, migratory, and invasive abilities of COAD cells were detected by CCK-8 and transwell assays, respectively. Correlations between TNNT1 and epithelial-mesenchymal transition (EMT)-related markers were determined using western blotting and Pearson's analysis. Our results stated that TNNT1 expression was high-regulated in COAD tissues, which was related with unfavorable prognosis of COAD patients. Functional analyses suggested that TNNT1 promoted the cellular behaviors. Moreover, aberrant expression of TNNT1 affected the expression level of EMT-related proteins. And TNNT1 was negatively linked with E-cadherin. In conclusion, our findings indicated that TNNT1 may promote the progression of COAD, mediating EMT process, and thus shed a novel light on COAD therapeutic treatments.

Extensive lymphatic spread of papillary thyroid microcarcinoma is associated with an increase in expression of genes involved in epithelial-mesenchymal transition and cancer stem cell-like properties

Background

Active surveillance is an alternative management for patents with low‐risk papillary thyroid microcarcinoma (PTMC); however, there is an absence of specific molecular markers that predict its progression. We compared gene expression patterns between PTMC with lateral neck‐node metastasis (N1b) and PTMC‐lacking nodal metastasis (N0).

Methods

We performed oligonucleotide microarray analysis in three PTMCs without cervical lymph‐node metastases (N0), and five PTMCs with lateral neck‐node metastasis (N1b) at initial diagnosis, using an Illumina HumanHT‐12 v4.0 Expression BeadChip. Quantitative real‐time PCR (qPCR) and western blot analysis confirmed microarray data. We performed immunohistochemistry (IHC) to confirm protein overexpression in samples from 20 N0 and 24 N1b PTMC patients who underwent thyroidectomy.

Results

Microarray analyses identified 52 probes corresponding to 45 genes. Expression of these genes differed significantly between the two PTMC groups. Forty genes were significantly upregulated and five genes were downregulated in N1b PTMC compared to N0. Four genes related to epithelial‐to‐mesenchymal transition (EMT) and stem cell markers, including ALDH1A3, TM4SF1, PROM1, and CAV1 were significantly upregulated in N1b PTMCs. Real‐time qPCR confirmed this expression and western blot analysis confirmed higher expression of ALDH1A3, TM4SF1, PROM1, and CAV1 in N1b than in N0 PTMCs. IHC indicated overexpression of ALDH1A3 and CAV1 in N1b compared to N0 PTMCs.

Conclusions

Genes related to EMT and thyroid cancer stem cell‐like properties are upregulated in early extensive lymphatic spread of PTMC.

Inhibitor of growth 4 (ING4) inhibits hypoxia-induced EMT by decreasing HIF-1α and snail in HK2 cells

Renal fibrosis is a common mechanism that leads to all kidney diseases and Epithelial-mesenchymal transition (EMT) is considered as one of the potential mechanisms of renal fibrosis. Inhibitor of growth 4 (ING4) was reported to involve in several diseases; especially it was negatively correlated with lung fibrogenesis parameters. However, the role of ING4 and underlying mechanisms in EMT are still unknown. In this study, we used a UUO rat model to mimic renal fibrosis, which was examined by Masson and HE staining analysis. To explore the effects of ING4 on hypoxia-induced EMT, HK2 cells were treated with hypoxia to induce EMT and ING4 was over-expressed in hypoxia-treated HK2 cells by transfection of pEGFP-N1-ING4. MTT assay was used to describe the cell viability of HK2 cells under the hypoxic condition. The expression levels of ING4, hypoxia-inducible factor-1α (HIF-1α), and EMT markers (E-cadherin, N-cadherin and vimentin) were examined in vivo and in vitro by western blot, qRT-PCR, immunohistochemical staining or Immunofluorescence. Our results showed that, in a UUO rat model, ING4 was decreased and EMT was developed with reduction in E-cadherin and increase in N-cadherin and vimentin, suggesting a significant association between ING4 expression and EMT. Under hypoxia, E-cadherin was down-regulated and N-cadherin and vimentin were up-regulated, indicating that hypoxia induced EMT in HK2 cells. Nonetheless, changes in the expression of EMT biomarkers were inhibited by over-expression of ING4. Moreover, over-expressing ING4 decreased the expression of HIF-1α and snail in HK2 cells. These findings suggest that ING4 may inhibit hypoxia-induced EMT via decreasing HIF-1α and snail in HK2 cells, indicating the potential of ING4 as a therapeutic target for renal fibrosis.

Retracted Article: Knockdown of TMPRSS11D inhibits the proliferation, migration and invasion of cervical cancer cells

TMPRSS11D is a member of the type II transmembrane serine proteases (TTSPs) family that is implicated in the development and progression of several cancers. However, the biological roles of TMPRSS11D in cervical cancer have not been investigated. In the present study, we detected the expression levels of TMPRSS11D in human cervical cancer tissues and cell lines. The results showed that TMPRSS11D expression was significantly upregulated in cervical cancer tissues as compared to the adjacent normal tissues. Besides, TMPRSS11D was highly expressed in human cervical cancer cell lines. Then we knocked down TMPRSS11D in cervical cancer cell lines to evaluate the effects of TMPRSS11D knockdown on cervical cancer cells. The results showed that knockdown of TMPRSS11D significantly suppressed cell proliferation, migration and invasion in cervical cancer cell lines. Furthermore, the data revealed that TMPRSS11D knockdown prevented epithelial–mesenchymal transition (EMT), as proved by the increased E-cadherin expression, as well as decreased N-cadherin and fibronectin expressions. Additionally, knockdown of TMPRSS11D inhibited the activation of the PI3K/Akt pathway in cervical cancer cells. Furthermore, insulin-like growth factor-1 (IGF-1) treatment reversed the inhibitory effects of TMPRSS11D knockdown on cell proliferation and migration. Collectively, knockdown of TMPRSS11D exerted anti-tumor activity, at least in part, via inhibiting the PI3K/Akt pathway. These findings indicated that TMPRSS11D might serve as a novel therapeutic target for the treatment of cervical cancer.

TMPRSS11D is a member of the type II transmembrane serine proteases (TTSPs) family that is implicated in the development and progression of several cancers.

Methanol Extract of Aerial Parts of Pavetta indica L. Enhances the Cytotoxic Effect of Doxorubicin and Induces Radiation Sensitization in MDA-MB-231 Triple-Negative Breast Cancer Cells

Pavetta indica L. is used in traditional medicine for the treatment of various diseases including hemorrhoids, headache, urinary conditions, ulcerated nose, and dropsy. However, no study has evaluated the anticancer effect of P. indica L. In this study, we found that a methanol extract of the leaves and branches of P. indica L. (MEPI) caused cellcycle arrest at the sub-G1 phase and induced apoptosis, as indicated by the activation of caspase-8, -3, -7, and c-PARP. Western blotting revealed that MEPI significantly reduced the levels of markers of the epithelial-mesenchymal transition, such as Vimentin, Snail, Slug, and matrix metallopeptidase 9. Notably, the expression of multidrug resistance-associated protein 1 in triple negative breast cancer (TNBC) was significantly decreased by MEPI. Moreover, the co-treatment with MEPI and doxorubicin resulted in a synergistic reduction in cell viability. MEPI also induced radiation sensitization of TNBC cells. Gas chromatography-mass spectrometry analysis revealed that 5,6-dehydrokawain (DK) is the major constituent of MEPI. Interestingly, DK exerted significant anti-invasive and anti-metastatic effects. Our results provide a strong rationale for investigating the molecular mechanisms of action of MEPI in TNBC.

Metformin Inhibits Epithelial-to-Mesenchymal Transition of Keloid Fibroblasts via the HIF-1α/PKM2 Signaling Pathway

Background: Epithelial-to-mesenchymal transition (EMT) is a process whereby epithelial cells lose cell-cell contacts and acquire expression of mesenchymal components and manifest a migratory phenotype. Recent studies indicated that EMT is involved in the development of keloids. Therefore, this study aims to investigate the mechanisms of the effects of metformin in hypoxia-induced EMT in keloid fibroblasts (KFs). Methods: KFs were cultured in a hypoxia incubator to induce EMT and were treated with or without metformin. Cell viability was evaluated by a cell counting kit 8 (CCK-8), and cell migration was measured by the transwell assay. The expression levels of HIF-1α, E-cadherin, vimentin, phosphorylated p70s6k (p-p70s6k) and pyruvate kinase M2 (PKM2) were evaluated by western blotting. Results: Hypoxia promoted EMT in KFs. Metformin significantly inhibited the expression of HIF-1α and partially abolished hypoxia-induced EMT. PKM2 is involved in hypoxia-induced EMT of KFs and metformin decreased the expression of p-p70s6k and PKM2. Conclusions: Metformin abolishes hypoxia-induced EMT in KFs by inhibiting the HIF-1α/PKM2 signaling pathway. Our study provides a novel mechanistic insight into potential use of metformin for treatment of keloids.

Prognostic and clinicopathological significance of circulating tumor cells in osteosarcoma

Osteosarcoma is the most common form of primary malignant bone tumor, with metastasis playing an essential role in determining a patient's prospects for survival. It is essential that new and better molecular targets that respond effectively to therapies and are predictive of the risk of tumor metastasis are identified. We have therefore undertaken the present prospective study to ascertain the clinical significance of circulating tumor cells (CTCs) in osteosarcoma patients. Peripheral blood was obtained from patients both pre- and post-surgery then processed using a CanPatrol™ system, an enrichment technique allowing isolation of CTCs by virtue of their size at baseline. Multiplex RNA in situ hybridization (RNA-ISH) was subsequently conducted to characterize the CTCs based on various molecular markers including MTA1, CD45, EpCAM, CK8, CK19, Vimentin and Twist. MTA1 expression was further validated by immunohistochemistry of the tumor tissue. Besides defining a diagnosis and prognosis for osteosarcoma patients, the correlation between CTC count and their molecular and clinicopathological characteristics was found to assist in the analysis of the response of patients to neoadjuvant chemotherapy. Our results revealed that the number of CTCs was significantly higher at baseline in metastatic patients than in those whose osteosarcomas were localized. The variation was attributed to the neoadjuvant chemotherapy treatment. A cut-off value of 7 CTCs/5 mL was found to effectively distinguish patients who had either a favorable or unfavorable prognosis. Notably, the ratio of mesenchymal CTCs at baseline was found to be higher in metastatic vs. localized osteosarcoma patients. In addition, the expression of MTA1 was higher in mesenchymal CTCs than the other CTC phenotypes. Furthermore, immunohistochemical analysis demonstrated a higher expression of MTA1 in tumor tissues from metastatic osteosarcoma patients. Taken together, our findings conclusively establish that the number and molecular phenotype of CTCs are predictive of tumor metastasis and the response of patients to neoadjuvant chemotherapy.

Oct4 Gene Expression in Primary Colorectal Cancer Promotes Liver Metastasis

PURPOSE

The Oct4 gene plays an important role in undifferentiated embryonic stem cells and regulates stem cell pluripotency. The aim of this study was to examine the relationship between Oct4 expression and liver metastasis of colorectal cancer (CRC) in clinical samples and investigate the role and abilities of Oct4-positive CRC cells.

METHODS

The study included 158 patients who underwent surgery for CRC between 2009 and 2011. The correlations between the Oct4 gene expression and the clinical parameters were assessed, and liver metastasis-free survival (LMFS) was evaluated in these patients. Oct4-EGFP-positive cells were established to examine their subpopulation and ability. The capacity to form liver metastasis in vivo was examined using CRC cell lines and primary cultured CRC cells.

RESULTS

LMFS was significantly poor in the Oct4 high-expression group compared with the low-expression group (P = 0.008). Multivariate analyses showed that Oct4 expression (P = 0.015) and TNM stage (P < 0.001) were significantly correlated with LMFS. Oct4-EGFP-positive cells highly expressed stem cell-associated markers and had self-renewal and differentiation abilities. Oct4-high cells actively formed liver metastasis.

CONCLUSION

The Oct4 expression was correlated with liver metastasis in CRC patients. Oct4 expression cells have self-renewal and differentiation abilities like those of cancer stem cells. Oct4 contributed to forming liver metastasis in CRC.

Inflammation: A key process in skin tumorigenesis

The extremely delicate shift from an inflammatory process to tumorigenesis is a field of major scientific interest. While the inflammation induced by environmental agents has well known underlying mechanisms, less is known concerning the oncogenic changes that follow an inflammatory chronic status in the tissue microenvironment that can lead to pro-tumorigenic processes. Regardless of the origin of the environmental factors, the maintenance of an inflammatory microenvironment is a clear condition that favors tumorigenesis. Inflammation sustains the proliferation and survival of malignant transformed cells, can promote angiogenesis and metastatic processes, can negatively regulate the antitumoral adaptive and innate immune responses and may alter the efficacy of therapeutic agents. There is an abundance of studies focusing on molecular pathways that trigger inflammation-mediated tumorigenesis, and these data have revealed a series of biomarkers that can improve the diagnosis and prognosis in oncology. In skin there is a clear connection between tissue destruction, inflammation and tumor onset. Inflammation is a self-limiting process in normal physiological conditions, while tumor is a constitutive process activating new pro-tumor mechanisms. Among skin cancers, the most commonly diagnosed skin cancers, squamous cell carcinoma and basal cell carcinoma (BCC) have important inflammatory components. The most aggressive skin cancer, melanoma, is extensively research in regards to the new context of novel developed immune-therapies. In skin cancers, inflammatory markers can find their place in the biomarker set for improvement of diagnosis and prognosis.

Exosomal Tenascin-c induces proliferation and invasion of pancreatic cancer cells by WNT signaling

Background: Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive gastrointestinal malignancies. PDAC has an unfavorable prognosis and a 5-year survival rate of less than 6%. Early diagnosis is difficult and the disease progresses rapidly. Local invasion and distant metastases are the underlying reasons for PDAC patient death.

Materials and Methods: By exosome proteomic analysis of homologous cell lines, we identified several proteins that distinguished highly- from less-invasive pancreatic cancer cells in situ. The third most prominent protein, Tenascin-c (TNC), was chosen to assess effects on the malignant characteristics of pancreatic cancer cells.

Results: Silencing of TNC by short hairpin RNA (shRNA) in the cell lines PC-1.0 and Aspc-1 changed cellular proliferation, apoptosis, migration, and invasion. TNC expression was found to be positively related to proliferation and apoptosis, with each of these two processes reinforcing the other and regulated by the nuclear factor (NF)-κB pathway. TNC was found to promote PDAC cell line epithelial-mesenchymal transition by regulation of the Wnt/β-catenin pathway.

Conclusions: This study demonstrated exosomal TNC to be closely associated with malignant features of pancreatic cancer cells including local invasion and distant metastasis. Hence, TNC is a potential therapeutic target for the treatment of PDAC invasiveness.

EVI1 promotes epithelial-to-mesenchymal transition, cancer stem cell features and chemo-/radioresistance in nasopharyngeal carcinoma

BACKGROUND

Aberrant EVI1 expression is frequently reported in cancer studies; however, its role in nasopharyngeal carcinoma (NPC) has not been examined in detail. The aim of the present study is to investigate the involvement of EVI1 in progression and prognosis of NPC.

METHODS

RT-PCR, immunohistochemistry and western blot assays were used to examine the expression of EVI1 in NPC tissues and cell lines. Fluorescence in situ hybridization assay was used to examine the amplification of EVI1 in NPC tissues. The biological effect of EVI1 was determined by both in vitro and in vivo studies. The dual-luciferase reporter assay was performed to confirm that EVI1 bind at E-cadherin andβ-catenin promoters. The ChIP, EMSA, and coimmunoprecipitation combined with mass spectrometry assays were used to analyze the EVI1 regulated proteins.

RESULTS

EVI1 expression level was up-regulated in NPC tissues and cell lines. EVI1 was amplificated in NPC tissues. We observed that EVI1 down-regulation decreased the cell proliferation and invasive capacity of NPC cells in vitro and in vivo. EVI1, snail, and HDAC1 formed a co-repressor complex to repress E-cadherin expression and ultimately contributed to epithelial mesenchymal transition (EMT) phenotype in NPC cells. In another way, EVI1 directly bound at β-catenin promoter and activated its expression. β-catenin mediated EVI1's function on cancer stem cells (CSCs) properties. EVI1 up-regulation predicted unfavorable prognosis and contributed to chemo/radio-resistance in NPC cells. Finally, we constructed arsenic trioxide-loaded nanoparticles (ALNPs) and revealed that ALNPs exerted anti-tumor effect in NPC cells.

CONCLUSIONS

Our data indicated that EVI1 played an oncogenic role in NPC growth and metastasis and that EVI1 might serve as a novel molecular target for the treatment of NPC.

Repositioning of fluoroquinolones from antibiotic to anti-cancer agents: An underestimated truth

Increasing development costs and higher failure rate in clinical trials has reduced the repertoire of newer drugs in the market for clinical use. The most appropriate approach to end the search for newer drugs is "Repositioning", as it requires less time and money to explore new indication of existing drug or failed drug. In the past, several drugs have been repositioned for different indication but the full potential remains unharnessed. With rise in cancer prevalence and treatment costs, it is imperative to search for newer drugs and the use of repositioning approach may help us. Fluoroquinolones has been used as antibiotics for over four decades now, but recent research highlighted their use as pharmacological compounds with multifaceted implication. Repositioning of fluoroquinolones into anti-cancer molecule seems to be a highly plausible option owing to their profound immunomodulatory, pro-apoptotic, anti-proliferative and anti-metastatic potential. The present review provides a comprehensive account of the recent and past explorations pertaining to the anti-cancer activity of fluoroquinolones and also discusses the various approaches that are being considered to remodel them for the treatment of cancer.

Epithelial-to-mesenchymal transition status of primary breast carcinomas and its correlation with metastatic behavior

Background

Epithelial-to-mesenchymal transition (EMT) has been implicated as an important step in the development of distant metastases. We therefore wished to study EMT status of primary breast carcinomas from patients who during follow-up developed distant metastases.

Methods

mRNA expression profiles of primary breast carcinoma samples (n = 151) from patients who developed metastatic disease were analyzed and EMT status was designated using a previously described EMT-core signature. EMT status of the primary tumor was correlated to clinicopathological characteristics, molecular subtypes, metastasis pattern, chemotherapy response and survival outcomes. In addition, using immunohistochemistry, the expression levels of several proteins implicated in EMT were studied (CDH1, CDH2, NAT1, SNAI2, TWIST1, VIM, and ZEB1) compared with the designated EMT status and survival.

Results

Utilizing the 130-gene-EMT-core signature, 66.2% of the primary tumors in the current study was assessed as EMT-activated. In contrast to our expectations, analyses revealed that 84.6% of Luminal A tumors, 65.1% of Luminal B tumors, and 55.6% of HER2-like had an activated EMT status, compared to only 25% of the basal-type tumors (p < 0.001). EMT status was not correlated to the pattern of metastatic disease, metastasis-specific survival, and overall survival. Similarly, there was not a significant association between EMT status of the primary tumor and chemotherapy response in the metastatic setting. Immunostaining for NAT1 and TWIST1 correlated with the EMT status (p 0.003 and p 0.047, respectively). Multivariate analyses showed that NAT1 and TWIST1 staining was significantly associated with EMT status regardless of the estrogen receptor status of the tumors (p values: 0.020 and 0.027, respectively).

Conclusions

The EMT status of breast cancers, as defined by the presence of a core EMT gene expression signature is associated with non-basal-type tumors, but not with the pattern of distant metastasis. Of several potential immunohistochemical EMT markers, only NAT1 and TWIST1 expression levels were associated with the gene expression-based EMT status.

Electronic supplementary material

The online version of this article (10.1007/s10549-018-05089-5) contains supplementary material, which is available to authorized users.

Paracrine signals of mesenchymal stem cells induce epithelial to mesenchymal transition in gastric cancer cells

AIM

Given the high similarity of phenotypical and secretory properties of mesenchymal stem cells and fibroblasts, this study investigated the possibility of inducing EMT process by mesenchymal stem cells.

BACKGROUND

Annually, more than 13% of deaths worldwide occur due to cancer. One of the main reasons for the high mortality rate is due to the metastasis of cancer stem cells. Induction of metastasis occurs during the EMT process, which can also be stimulated by fibroblast cells.

METHODS

Mesenchymal stem cells (MSCs) were isolated and sub-cultured until passage 3 or 4. AGS cells were co-cultured with MSCs for 4 days. As the positive control group, AGS cells were treated with TGF-β (10ng/ml) for 48h. Finally, the mRNA expression level of Vimentin, β-catenin, Snail, and E-cadherin as the EMT pattern, were evaluated by RT-PCR technique.

RESULTS

Our findings indicated that AGS cells' crosstalk with MSCs significantly upregulated fibroblast markers including Vimentin and Snail expression. However, no significant changes were identified for β-catenin gene expression. Additionally, AGS treatment with MSCs resulted in diminished E-cadherin in the targeted cells.

CONCLUSION

Based on the results, the AGS cells crosstalk with MSCs activates induction of epithelial mesenchymal transition, which is confirmed through the elevation of Vimentin and Snail expression and reduction of E-cadherin expression as a specific epithelial marker. However, it seems that MSc was not effective on Wnt/ β-catenin signal gastric cancer cell line.

MiR-495/IGF-1/AKT Signaling as a Novel Axis Is Involved in the Epithelial-to-Mesenchymal Transition of Oral Squamous Cell Carcinoma

PURPOSE

Increasing evidence suggests that aberrant expression of miR-495 is associated with the progression of various cancers. The aim of this study was to investigate the function and underlying mechanism of miR-495 in oral squamous cell carcinoma (OSCC).

MATERIALS AND METHODS

OSCC specimens and oral cancer cell lines, as well as the OSCC microRNA expression profile from the Gene Expression Omnibus database, were used to detect the expression of miR-495 in OSCC. Cell proliferation, migration, and invasion assays were performed to analyze the function of miR-495. Bioinformatics and luciferase reporter assays were used to identify the target gene of miR-495. Pearson analysis was carried out to investigate the correlation between miR-495 and insulin-like growth factor 1 (IGF1) or AKT levels. Transfection of pcDNA3.1 vector and small interfering RNA was performed to overexpress or downregulate the expression of IGF1. OSCC xenografts in mice were constructed to validate the function and mechanism of miR-495 in vivo.

RESULTS

MiR-495 was downregulated in OSCC tissues and cell lines, and it markedly inhibited cell proliferation, migration, and invasion, as well as epithelial-to-mesenchymal transition (EMT)-related proteins of OSCC cells. IGF1 was identified as a direct target gene of miR-495. Besides, AKT was confirmed to be regulated by miR-495/IGF-1 signaling, and miR-495 was negatively correlated with IGF1 and AKT in OSCC. In vivo, miR-495 inhibited the growth and EMT-related proteins of OSCC xenografts in mice.

CONCLUSIONS

The miR-495/IGF-1/AKT signaling axis played a tumor-suppressive role in OSCC by regulating cell proliferation, invasion, and migration, as well as EMT.

Nanoparticle Delivery of TWIST Small Interfering RNA and Anticancer Drugs: A Therapeutic Approach for Combating Cancer

Breast and ovarian cancer are the leading cause of cancer-related deaths in women in the United States with over 232,000 new Breast Cancer (BC) diagnoses expected in 2018 and almost 40,000 deaths and an estimated 239,000 new ovarian cancer (OC) cases and 152,000 deaths worldwide annually. OC is the most lethal gynecologic malignancy. This high mortality rate is due to tumor recurrence and metastasis, primarily caused by chemoresistant cancer stem-like cells (CSCs). Triple Negative Breast Cancer (TNBC) patients also become resistant to chemotherapy due to recurrence of CSCs. Currently, no ovarian or breast cancer therapies target CSC specifically. TWIST is overexpressed in the majority of chemoresistant cancers resulting in a low survival rate. Our long-term goal is to develop novel treatments for women with ovarian and breast cancer, specifically treatments that sensitize chemoresistant tumors. Despite successful initial surgery and chemotherapy, over 70% of advanced EOC will recur, and only 15-30% of recurrent disease will respond to chemotherapy (Cortez et al., 2017; Berezhnaya, 2010; Jackson et al., 2015). Moreover, drug resistance causes treatment failure in over 90% of patients with metastatic disease (Solmaz et al., 2015). Thus, recurrent metastatic disease is a major clinical challenge without effective therapy. One of the major challenges in the treatment of breast cancer is the presence of a subpopulation of cancer cells that are chemoresistant (CRC) and metastatic. Given that metastasis is the driving force behind mortality for breast and ovarian cancer patients, it is essential to identify the characteristics of these aberrant cancer cells that allow them to spread to distant sites in the body and develop into metastatic tumors. Understanding the metastatic mechanisms driving cancer cell dispersal will open the door to developing novel therapies that prevent metastasis and improve long-term outcomes for patients. In this chapter we assess the feasibility of targeting the Twist and EMT signaling pathways in breast and ovarian cancer. Additional discussions of the pathways that mediate epithelial-mesenchymal transition (EMT), a process that can give rise to chemoresistance. We review potential treatment strategies for targeting EMT and drug resistance as well as the problems that may arise with these targeted delivery therapeutic approaches. Finally, we examine recent advances in the field, including cancer stem cell targeted nanoparticle delivery and small interference RNA (siRNA) technology, and discuss the impact that these approaches may have on translating much needed therapeutic approaches into the clinic, for the benefit of patients battling this devastating disease.

NEAT1 contributes to the CSC-like traits of A549/CDDP cells via activating Wnt signaling pathway

Long non-coding RNAs (lncRNAs) have been identified to exert crucial roles in tumorigenesis and can serve as novel biomarkers for cancer therapy including lung cancer. Cisplatin is a first-line chemotherapeutic agent in non-small cell lung cancer (NSCLC), but the therapeutic effect is unsatisfactory, partly due to drug resistance. Emerging evidence showed that chemo-resistance is associated with acquisition of cancer stem cell (CSC)-like properties. Cisplatin resistance remains a major obstacle in the treatment of lung cancer, and its mechanism is still not fully elucidated. Meanwhile, CSCs have been involved in tumor metastasis, tumor recurrence and chemotherapy resistance. So far, the mechanism of nuclear enriched abundant transcript 1 (NEAT1) in modulating CSCs in lung cancer remains barely known. Therefore, we aimed to explore the correlation between NEAT1 and cancer stem cells in lung cancer. In our current study, we observed that CSC-like traits were much more enriched in cisplatin-resistant A549/CDDP cells. In addition, NEAT1 was obviously up-regulated in A549/CDDP cells compared with parental A549 cells. Knockdown of NEAT1 decreased the CSC-like properties of A549/CDDP cells through inhibiting tumor cell sphere volume, repressing CSC-like biomarkers levels and restraining CD44 positive cell ratios. Oppositely, overexpression of NEAT1 enhanced the stemness respectively. Moreover, it has been reported that Wnt pathway is implicated in many vital cellular functions including cancer stem cells. Here, it was exhibited that Wnt signal pathway was inactivated by knockdown of NEAT1 whereas activated by NEAT1 overexpression in A549/CDDP cells. Taken these together, it was indicated that NEAT1 could exert a novel biological role in NSCLC chemo-resistance.

MicroRNA expression profiles identify biomarkers for predicting the response to chemoradiotherapy in rectal cancer

Neoadjuvant chemoradiotherapy (nCRT) following surgery significantly improves the survival rate of patients with rectal cancer. However, nCRT is associated with significant adverse symptoms and high medical costs. Therefore, it is important to investigate potential biomarkers for the prediction of the response to nCRT in patients with rectal cancer. The present study identified candidate biomarkers for predicting a complete response (CR) to nCRT in patients with rectal cancer and investigated the associated mechanisms. Microarray data (accession no. GSE29298) was downloaded from the Gene Expression Omnibus database. Differentially expressed microRNAs (miRNAs/miR) were screened between the pathological CR (pCR) group and no pCR (incomplete response) group. miRNA target genes were predicted using the miRWalk 2.0 online tool and subjected to Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis. Furthermore, a miRNA co‑regulatory network was constructed and disease‑associated genes were predicted. The results demonstrated that a total of 36 upregulated and 5 downregulated miRNAs were identified between the two groups. Among these differentially expressed miRNAs, miR‑548c‑5p, miR‑548d‑5p and miR‑663a were significantly associated with a CR to nCRT. The co‑regulatory network and pathway analysis indicated that miR‑548c‑5p and miR‑548d‑5p may function together through stem cell pluripotency and ubiquitin‑mediated proteolysis signaling pathways. Furthermore, the prediction of disease‑associated genes demonstrated that miR‑548c‑5p/miR‑548d‑5p and miR‑663a may regulate genes associated with rectal cancer, including mutated in colorectal cancers (MCC) and adenomatous polyposis coli (APC), and colorectal neoplasms, including interleukin‑6 signal transducer (IL6ST), cell cycle checkpoint kinase 2 (CHEK2), marker of proliferation Ki‑67 (MKI67), cadherin 7 (CDH7), calreticulin (CALR) and transforming growth factor β1 (TGFB1). Therefore, miR‑548c‑5p, miR‑548d‑5p and miR‑663a are promising candidate biomarkers for predicting a CR to nCRT. miR‑548c‑5p/miR‑548d‑5p may be associated with a CR by regulating IL6ST, CHEK2, MKI67 and MCC. In addition, it may function through the pluripotency of stem cells and ubiquitin‑mediated proteolysis signaling pathways. miR‑663a may be associated with a CR to nCRT by targeting CDH7, CALR, APC and TGFβ1. Thus, the miRNA biomarkers investigated in the present study may represent novel therapeutic targets for the prediction and eventual improvement of the response to nCRT in patients with rectal cancer.

DcR3 induces proliferation, migration, invasion, and EMT in gastric cancer cells via the PI3K/AKT/GSK-3β/β-catenin signaling pathway

Background

Decoy receptor 3 (DcR3) has been reported to be overexpressed in a wide variety of malignancies and is correlated with tumorigenesis and progression. In gastric cancer (GC), DcR3 overexpression is associated with lymph node and distant metastasis, as well as poor prognosis. However, the functional role of DcR3 expression in GC remains elusive.

Purpose

The aim of this study is to elucidate the direct role of DcR3 in regulating GC progression and metastasis and identify the potential mechanism.

Methods

DcR3 expression was stably knocked down in HGC27 and MKN28 cells by transfecting the cells with DcR3 shRNA using lentiviral vector system. After the knockdown of DcR3 was confirmed, cell proliferation, colony formation, cell cycle distribution, apoptosis, cell invasion and migration were assessed in vitro. In addition, Western blot analysis was performed to evaluate the expression of downstream mediators of DcR3. Comparisons between multiple groups were performed using one-way analysis of variance (ANOVA) or unpaired Student’s t-test. Differences were considered significant at P<0.05.

Results

Our findings demonstrate that DcR3 induces proliferation, migration, invasion, and promotes epithelial-mesenchymal transition (EMT) of GC cells. In addition, DcR3 increases the expression levels of several components of the PI3K/AKT/GSK-3β/β-catenin signaling pathway, such as p-AKT, GSK-3β, p-GSK-3β and β-catenin. Additionally, DcR3 also enhances the expression of N-cadherin and Vimentin and decreases the expression of E-cadherin.

Conclusion

In summary, the findings of this study indicate that during GC progression, DcR3 plays a key role in cell proliferation and invasion via the PI3K/AKT/GSK-3β/β-catenin signaling pathway. Thus, targeting DcR3 might be a potential therapeutic approach for the treatment of GC.

Fibulin-3 knockdown inhibits cervical cancer cell growth and metastasis in vitro and in vivo

To explore the function of fibulin-3 in cervical carcinoma malignant cell growth and metastasis, fibulin-3 expression in normal cervical tissue, cervical intraepithelial neoplasia (CIN), and cervical carcinoma were evaluated by immunohistochemistry. Quantitative real-time-polymerase chain reaction, western blotting, and immunocytochemistry were performed to assess the expression of fibulin-3 at mRNA and protein levels in different invasive clone sublines. Fibulin-3 shRNA and fibulin-3 cDNA were used to transfect the strongly and weakly invasive clone sublines. Using in vitro and in vivo functional assays, we investigated the effects of down-regulating and up-regulating fibulin-3 expression on the proliferation and invasion of different clone sublines. Epithelial mesenchymal transition (EMT) and its signaling pathways PI3K/AKT and ERK were studied carefully in lentiviral transfection systems. Fibulin-3 was upregulated in cervical carcinoma, and its overexpression was significantly related with malignant phenotype and poor prognosis of cervical carcinoma. Fibulin-3 promoted cervical cancer cell invasive capabilities by eliciting EMT and activating the PI3K-Akt-mTOR signal transduction pathway. Fibulin-3 could facilitate the process of cervical cancer development. The results presented here will help develop novel prognostic factors and possible therapeutic options for patients with cervical cancer.

Hyperbaric oxygen therapy can ameliorate the EMT phenomenon in keloid tissue

BACKGROUND

Hyperbaric oxygen therapy (HBOT) has been widely used in the clinical setting. In this study, HBOT therapy was evaluated for its ability to ameliorate the epithelial-to-mesenchymal transition (EMT) phenomenon in keloid tissue.

METHODS

Keloid patients were randomly divided into two groups: keloid patients (K group, 9 patients) and keloid patients receiving HBOT (O group, 9 patients). A third group with normal skin (S group, 9 patients) was established for control. Before HBOT and surgery, a laser Doppler flowmeter was used to measure the keloid blood supply of patients in the O group. Hematoxylin and eosin (H&E) staining was used to observe morphology. E-cadherin, ZO-1, vimentin, fibronectin, vascular endothelial growth factor (VEGF), and hypoxia inducible factor (HIF)-1α were measured by immunofluorescence staining and Western blot analysis. Real-time quantitative polymerase chain reaction (RT-qPCR) was used to evaluate the mRNA expression level of these factors as well.

RESULTS

In the O group, keloid blood perfusion was significantly reduced after patients received HBOT. Compared with the K group, lower expression levels of vimentin, vibronectin, VEGF, and HIF-1α were observed in the O group, whereas the expression of E-cadherin and ZO-1 was significantly higher. The mRNA expression of E-cadherin and ZO-1 was also increased after HBOT.

CONCLUSIONS

The expression levels of factors related to the EMT phenomenon were significantly reversed in keloid patients after they received HBOT, indicating that HBOT may be an effective therapy against the EMT phenomenon in keloid patients.

Histone Deacetylases as New Therapeutic Targets in Triple-negative Breast Cancer: Progress and Promises

Triple-negative breast cancer (TNBC) lacks expression of estrogen receptor (ER), progesterone receptor (PR) and HER2 gene. It comprises approximately 15-20% of breast cancers (BCs). Unfortunately, TNBC's treatment continues to be a clinical problem because of its relatively poor prognosis, its aggressiveness and the lack of targeted therapies, leaving chemotherapy as the mainstay of treatment. It is essential to find new therapies against TNBC, in order to surpass the resistance and the invasiveness of already existing therapies. Given the fact that epigenetic processes control both the initiation and progression of TNBC, there is an increasing interest in the mechanisms, molecules and signaling pathways that participate at the epigenetic modulation of genes expressed in carcinogenesis. The acetylation of histone proteins provokes the transcription of genes involved in cell growth, and the expression of histone deacetylases (HDACs) is frequently up-regulated in many malignancies. Unfortunately, in the field of BC, HDAC inhibitors have shown limited effect as single agents. Nevertheless, their use in combination with kinase inhibitors, autophagy inhibitors, ionizing radiation, or two HDAC inhibitors together is currently being evaluated. HDAC inhibitors such as suberoylanilidehydroxamic acid (SAHA), sodium butyrate, mocetinostat, panobinostat, entinostat, YCW1 and N-(2-hydroxyphenyl)-2-propylpentanamide have shown promising therapeutic outcomes against TNBC, especially when they are used in combination with other anticancer agents. More studies concerning HDAC inhibitors in breast carcinomas along with a more accurate understanding of the TNBC's pathobiology are required for the possible identification of new therapeutic strategies.

MECHANISMS IN ENDOCRINOLOGY: Lessons from growth hormone receptor gene-disrupted mice: are there benefits of endocrine defects?

Growth hormone (GH) is produced primarily by anterior pituitary somatotroph cells. Numerous acute human (h) GH treatment and long-term follow-up studies and extensive use of animal models of GH action have shaped the body of GH research over the past 70 years. Work on the GH receptor (R)-knockout (GHRKO) mice and results of studies on GH-resistant Laron Syndrome (LS) patients have helped define many physiological actions of GH including those dealing with metabolism, obesity, cancer, diabetes, cognition and aging/longevity. In this review, we have discussed several issues dealing with these biological effects of GH and attempt to answer the question of whether decreased GH action may be beneficial.

The oncogenic effects of HES1 on salivary adenoid cystic carcinoma cell growth and metastasis

Background

Our previous study demonstrated a close relationship between NOTCH signaling pathway and salivary adenoid cystic carcinoma (SACC). HES1 is a well-known target gene of NOTCH signaling pathway. The purpose of the present study was to further explore the molecular mechanism of HES1 in SACC.

Methods

Comparative transcriptome analyses by RNA-Sequencing (RNA-Seq) were employed to reveal NOTCH1 downstream gene in SACC cells. Immunohistochemical staining was used to detect the expression of HES1 in clinical samples. After HES1-siRNA transfected into SACC LM cells, the cell proliferation and cell apoptosis were tested by suitable methods; animal model was established to detect the change of growth ability of tumor. Transwell and wound healing assays were used to evaluate cell metastasis and invasion.

Results

We found that HES1 was strongly linked to NOTCH signaling pathway in SACC cells. The immunohistochemical results implied the high expression of HES1 in cancerous tissues. The growth of SACC LM cells transfected with HES1-siRNAs was significantly suppressed in vitro and tumorigenicity in vivo by inducing cell apoptosis. After HES1 expression was silenced, the SACC LM cell metastasis and invasion ability was suppressed.

Conclusions

The results of this study demonstrate that HES1 is a specific downstream gene of NOTCH1 and that it contributes to SACC proliferation, apoptosis and metastasis. Our findings serve as evidence indicating that HES1 may be useful as a clinical target in the treatment of SACC.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4350-5) contains supplementary material, which is available to authorized users.

Loss of Stemness, EMT, and Supernumerary Tooth Formation in Cebpb-/-Runx2+/- Murine Incisors

Adult Cebpb KO mice incisors present amelogenin-positive epithelium pearls, enamel and dentin allopathic hyperplasia, fewer Sox2-positive cells in labial cervical loop epitheliums, and reduced Sox2 expression in enamel epithelial stem cells. Thus, Cebpb acts upstream of Sox2 to regulate stemness. In this study, Cebpb KO mice demonstrated cementum-like hard tissue in dental pulp, loss of polarity by ameloblasts, enamel matrix in ameloblastic layer, and increased expression of epithelial-mesenchymal transition (EMT) markers in a Cebpb knockdown mouse enamel epithelial stem cell line. Runx2 knockdown in the cell line presented a similar expression pattern. Therefore, the EMT enabled disengaged odontogenic epithelial stem cells to develop supernumerary teeth. Cebpb and Runx2 knockdown in the cell line revealed higher Biglycan and Decorin expression, and Decorin-positive staining in the periapical region, indicating their involvement in supernumerary tooth formation. Cebpb and Runx2 acted synergistically and played an important role in the formation of supernumerary teeth in adult incisors.

Genome-wide identification of epithelial-mesenchymal transition-associated microRNAs reveals novel targets for glioblastoma therapy

MicroRNAs (miRNA) regulate a number of cellular processes. Recent studies have indicated that these molecules function in the epithelial-mesenchymal transition (EMT). However, the crucial systematic role of EMT and miRNAs together in glioblastoma (GBM) remains poorly understood. The present study demonstrated that EMT was closely associated with malignant progression and clinical outcome using three independent glioma databases (GSE16011, Rembrandt and The Cancer Genome Atlas). Furthermore, integrated analysis of miRNAs and mRNA profiling in 491 GBM samples revealed an EMT biological process associated with an miRNA profile (19 positively and 18 negatively correlated miRNAs). Among these miRNAs, miR-95 and miR-223 indicated a high level of functional validation, reflecting their positive correlation with EMT. Additionally, the upregulation of miR-95, which was negatively correlated with EMT, inhibited cellular invasion in glioma U251 and LN229 cells and decreased the expression of the mesenchymal marker N-catenin, whereas an miRNA positively correlated with EMT, miR-223, exhibited the opposite effect. Therefore, the results of the present study could further enhance the current understanding of the functions of miRNAs in GBM, indicating that the EMT-specific miRNA signature may represent a novel target for GBM therapy.

A Synthetic Binder of Breast Cancer Stem Cells

Cancer stem cells (CSCs) are associated with drug resistance, metastasis and recurrence of cancer. A synthetic binder of CSCs can provide a valuable tool to study the biology of CSCs and a lead to develop imaging, diagnostic and therapeutic agents targeting CSCs. Herein, a synthetic ligand (1) that specifically binds to CSCs over non-CSCs of breast cancer cells was identified for the first time via a cell-binding screening of a chemical library. The ligand 1 showed specific binding to CD24^- /CD44⁺ /ALDH⁺ CSC population of MCF-7 and MDA-MB-231. We have demonstrated that 1-immobilized beads can be used as matrices for affinity isolation of 1-binding CSC population from breast cancer cells. The 1-binding population showed significantly increased expressions of stemness-associated transcription factors. Importantly, the 1-binding population demonstrated accelerated tumor growth in vivo, and the resulting tumor displayed an increased migratory activity and high expressions of CSC markers.

Oral cancer stem cells - properties and consequences

Research on cancer stem cells (CSCs) has greatly increased in the field of medicine and pathology; however, some conceptual misunderstandings are still present among the public as well as within the general scientific community that is not yet familiar with the subject. The very first problem is the misinterpretation of CSCs as a synonym of their normal counterparts, the well-known stem cells (SCs). Particularly in Dentistry, another common mistake is the misinterpretation of oral CSCs as normal tooth-derived SCs. The present review aims to clarify important concepts related to normal SCs and CSCs, as well as discuss the relevance of CSCs to the development, metastasis and therapy resistance of oral squamous cell carcinoma.

Targeting epithelial-mesenchymal transition and cancer stem cells for chemoresistant ovarian cancer

Chemoresistance is the main challenge for the recurrent ovarian cancer therapy and responsible for treatment failure and unfavorable clinical outcome. Understanding mechanisms of chemoresistance in ovarian cancer would help to predict disease progression, develop new therapies and personalize systemic therapy. In the last decade, accumulating evidence demonstrates that epithelial-mesenchymal transition and cancer stem cells play important roles in ovarian cancer chemoresistance and metastasis. Treatment of epithelial-mesenchymal transition and cancer stem cells holds promise for improving current ovarian cancer therapies and prolonging the survival of recurrent ovarian cancer patients in the future. In this review, we focus on the role of epithelial-mesenchymal transition and cancer stem cells in ovarian cancer chemoresistance and explore the therapeutic implications for developing epithelial-mesenchymal transition and cancer stem cells associated therapies for future ovarian cancer treatment.

Phosphoglycerate Mutase 1 (PGAM1) Promotes Pancreatic Ductal Adenocarcinoma (PDAC) Metastasis by Acting as a Novel Downstream Target of the PI3K/Akt/mTOR Pathway

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive tumors known, with an overall 5-year survival rate of less than 6% due to early local invasion and distant metastasis. Exploring suitable therapeutic targets associated with invasion and metastasis is required for improving the prognosis of PDAC. In this study, we investigated the role of the glycolytic enzyme phosphoglycerate mutase 1 (PGAM1) in PDAC. PGAM1 expression was examined in tissue samples of 54 PDAC patients using immunohistochemistry, and the correlation between clinicopathological expression and PGAM1 expression was determined. A survival curve was generated using the Kaplan–Meier method. After silencing PGAM1 by siRNA in pancreatic cancer cell lines Aspc-1 and Panc-1, the changes in proliferation, migration, and invasion, and signal pathways were determined. In this study, the expression of PGAM1 was found positively related to poor differentiation, metastasis, advanced clinical stage, and poor survival rate. Silencing PGAM1 decreased the proliferation of Aspc-1 and Panc-1 cells with an S phase arrest, but without influencing cell apoptosis. Migration and invasion also decreased significantly, independent of proliferation. PGAM1 was also found to promote EMT of PDAC cell lines by regulating the Wnt/β-catenin pathway. PGAM1 itself was modulated by the PI3K/Akt/mTOR pathway as a novel downstream target and has a positive mutual regulation with HIF-1α. This study indicates that PGAM1 is closely associated with clinical metastasis and poor prognosis of PDAC. PGAM1 is considered as a potential therapeutic target in PDAC metastasis.

Clinical Significance of Subtype Classification in Metastatic Lymph Nodes of Breast Cancer Patients Undergoing Neoadjuvant Chemotherapy

Background

Neoadjuvant chemotherapy has been increasingly utilized in the treatment of breast cancer patients. However, there are no established surrogate markers predicting the response to subsequent adjuvant therapy and clinical outcome of patients. In particular, whether primary or lymph nodes metastasis should be evaluated for these analyses has remained unknown. Therefore, in this study, we first evaluated the differences in biomarkers between primary and metastatic cancer tissues in the patients undergoing neoadjuvant chemotherapy. We then correlated the findings with the clinical outcomes of these patients.

Methods

We examined 49 patients receiving neoadjuvant chemotherapy and subsequent surgery with lymph node metastasis. Estrogen receptor (ER), progesterone receptor (PgR), human epidermal growth factor receptor 2 (HER2) and Ki-67 were all immunohistochemically evaluated in core needle biopsy samples from primary and metastatic tumors following chemotherapy.

Results

No statistically significant differences in these markers were detected between the primary tumor and metastatic lymph nodes following therapy, but the Ki-67 labeling index was significantly higher in metastatic lymph nodes than in primary tumor (p = 0.017). The patients associated with luminal A type carcinoma in their lymph nodes following chemotherapy demonstrated significantly better clinical outcomes (disease-free survival: p = 0.0045, overall survival: p = 0.0006) than those who were not.

Conclusion

These data indicate that subtype classification following chemotherapy, in the metastatic lymph nodes rather than primary tumor could predict long-term outcomes of patients undergoing neoadjuvant chemotherapy.

Epithelial Mesenchymal Transition in Embryonic Development, Tissue Repair and Cancer: A Comprehensive Overview

The epithelial mesenchymal transition (EMT) plays a central role in both normal physiological events (e.g., embryonic development) and abnormal pathological events (e.g., tumor formation and metastasis). The processes that occur in embryonic development are often reactivated under pathological conditions such as oncogenesis. Therefore, defining the regulatory networks (both gene and protein levels) involved in the EMT during embryonic development will be fundamental in understanding the regulatory networks involved in tumor development, as well as metastasis. There are many molecules, factors, mediators and signaling pathways that are involved in the EMT process. Although the EMT is a very old topic with numerous publications, recent new technologies and discoveries give this research area some new perspective and direction. It is now clear that these important processes are controlled by a network of transcriptional and translational regulators in addition to post-transcriptional and post-translational modifications that amplify the initial signals. In this review article, we will discuss some key concepts, historical findings, as well as some recent progresses in the EMT research field.

Discovering alkylamide derivatives of bexarotene as new therapeutic agents against triple-negative breast cancer

Triple-negative breast cancer (TNBC) has been reported to be correlated with high expression of proliferation markers as well as constitutive activation of metastasis-relevant signaling pathways. For many years, breast cancer researchers have been investigating specific and effective methods to treat or to control the development of TNBC, but promising therapeutic options remain elusive. In this study, we have demonstrated that alkylamide derivatives of bexarotene DK-1-150 and DK-1-166 induce apoptotic cell death in TNBC cell lines without causing cytotoxicity in the normal mammary epithelial cell line. Furthermore, the bexarotene derivatives also showed significant effects in inhibiting TNBC cell proliferation and migration, modulating cancer stem cell markers expressions, as well as limiting the epithelial-mesenchymal transition (EMT) activities of TNBC cell lines in terms of downregulating EMT marker and blocking nuclear translocation of β-catenin. Therefore, we propose the alkylamide derivatives of bexarotene as potential candidates for novel anticancer therapeutics against TNBC.

Cdc20 overexpression is involved in temozolomide-resistant glioma cells with epithelial-mesenchymal transition

Glioma remains one of the most aggressive and lethal cancers in central nervous system. Temozolomide (TMZ) is the most commonly used chemotherapeutic agent in gliomas. However, therapeutic benefits of TMZ could be very limited and all patients would finally suffer from tumor progression as the tumors develop resistance to TMZ. In this study, we aim to investigate the underlying mechanism of chemoresistance in glioma cell line and to identify whether there is still a close link between epithelial-mesenchymal transition (EMT) and TMZ resistance in gliomas. The real-time RT-PCR and Western blotting were used to measure the expression of EMT markers in TMZ-resistant cells. The migration and invasion assays were conducted to detect the cell motility activity in TMZ-resistant cells. The transfection was used to down-regulate the Cdc20 expression. The student t-test was applied for data analysis. We established stable TMZ-resistant glioma cells and designated as TR. Our results revealed that TR cells exhibited a significantly increased resistance to TMZ compared with their parental cells. Moreover, TMZ-resistant cells had acquired EMT-like changes. For the mechanism study, we measured a significant increased expression of CDC20 and decreased expression of Bim in TR cells. Moreover, upon suppression of CDC20 by shRNA transfection, TR cells underwent a reverse of EMT features. Importantly, knockdown of CDC20 enhanced the drug sensitivity of TR cells to TMZ. Our results suggested that inactivation of CDC20 could contribute to the future therapy that possibly overcomes drug resistance in human cancers.