Targeting Integrin-Linked Kinase Suppresses Invasion and Metastasis through Downregulation of Epithelial-to-Mesenchymal Transition in Renal Cell Carcinoma

New Perspectives on the Role of Integrin-Linked Kinase (ILK) Signaling in Cancer Metastasis

Simple Summary

Today, the vast majority of deaths from cancer are due to cancer metastasis. Metastasis requires that cancer cells escape from the initial tumor, travel through blood vessels, and form new tumors in distant host tissues. Integrin-linked kinase (ILK) is overexpressed by many types of cancer cells and provides both structural and signaling functions that are important for successful metastasis. Here, we discuss recent findings that show how ILK is involved in promoting physical changes important for cell motility and invasion, and how ILK relays signals to other machinery components during metastasis, including interactions with components of the immune system and communication between cancer cells and normal cells, to affect the process of metastasis. We also discuss the contribution of ILK to therapeutic resistance and examine efforts to target ILK for the treatment of metastatic disease.

Abstract

Cancer metastasis is a major barrier to the long-term survival of cancer patients. In cancer cells, integrin engagement downstream of cell-extracellular matrix (ECM) interactions results in the recruitment of cytoskeletal and signaling molecules to form multi-protein complexes to promote processes critical for metastasis. One of the major functional components of these complexes is Integrin Linked Kinase (ILK). Here, we discuss recent advances in our understanding of the importance of ILK as a signaling effector in processes linked to tumor progression and metastasis. New mechanistic insights as to the role of ILK in cellular plasticity, epithelial mesenchymal transition (EMT), migration, and invasion, including the impact of ILK on the formation of invadopodia, filopodia-like protrusions (FLPs), and Neutrophil Extracellular Trap (NET)-induced motility are highlighted. Recent findings detailing the contribution of ILK to therapeutic resistance and the importance of ILK as a potentially therapeutically tractable vulnerability in both solid tumors and hematologic malignancies are discussed. Indeed, pharmacologic inhibition of ILK activity using specific small molecule inhibitors is effective in curtailing the contribution of ILK to these processes, potentially offering a novel therapeutic avenue for inhibiting critical steps in the metastatic cascade leading to reduced drug resistance and increased therapeutic efficacy.

Integrin-linked kinase affects the sensitivity of esophageal squamous cell carcinoma cells to chemotherapy with cisplatin via the Wnt/beta-catenin signaling pathway

Recent studies have shown that the expression of integrin-linked kinase (ILK) was related to the occurrence, development, and malignant progression of esophageal squamous cell carcinoma (ESCC). However, research on the relationship between ILK and the chemosensitivity of ESCC has to date not been reported. The present study found that ILK was highly expressed in ESCC cell lines, and the overexpression of ILK in ESCC cells reduced the incidence of cell apoptosis and alleviated the cytotoxicity on cells induced by cisplatin (CDDP). Inversely, ILK knockdown increased CDDP-induced apoptosis and had an inhibitive effect on the malignant phenotype of ESCC, including cell proliferation, invasion, and migration. In addition, ILK knockdown in ESCC cells inhibited the expression of beta (β)-catenin and activated the wingless/integrated (Wnt) signaling pathway. Furthermore, cellular MYC (c-MYC) and Cylin D1 were the target genes of the Wnt signaling pathway. Rescue experiments showed that the overexpression of β-catenin reversed a tumor’s inhibition and apoptosis abilities induced by ILK knockdown. In conclusion, ILK potentially reduced the CDDP sensitivity of ESCC cells by influencing the activity of the Wnt/β-catenin signaling pathway.

Functional interaction between endothelin-1 and ZEB1/YAP signaling regulates cellular plasticity and metastasis in high-grade serous ovarian cancer

Background

Epithelial-to-mesenchymal transition (EMT) encompasses a highly dynamic and complex key process which leads to metastatic progression. In high-grade serous ovarian carcinoma (HG-SOC), endothelin-1 (ET-1)/endothelin A receptor (ET_AR) signaling promotes EMT driving tumor progression. However, the complex nature of intertwined regulatory circuits activated by ET-1 to trigger the metastatic process is not fully elucidated.

Methods

The capacity of ET-1 pathway to guide a critical transcriptional network that is instrumental for metastatic growth was identified in patient-derived HG-SOC cells and cell lines through immunoblotting, q-RT-PCR, co-immunoprecipitation, in situ proximity ligation, luciferase reporter, chromatin immunoprecipitation assays and publicly available databases. Functional assays in HG-SOC cells and HG-SOC xenografts served to test the inhibitory effects of ET-1 receptors (ET-1R) antagonist in vitro and in vivo.

Results

We demonstrated that ET-1/ET_AR axis promoted the direct physical ZEB1/YAP interaction by inducing their nuclear accumulation in HG-SOC cells. Moreover, ET-1 directed their engagement in a functional transcriptional complex with the potent oncogenic AP-1 factor JUN. This led to the aberrant activation of common target genes, including EDN1 (ET-1) gene, thereby creating a feed-forward loop that sustained a persistent ET-1/ZEB1 signaling activity. Notably, ET-1-induced Integrin-linked kinase (ILK) signaling mediated the activation of YAP/ZEB1 circuit driving cellular plasticity, invasion and EMT. Of therapeutic interest, treatment of HG-SOC cells with the FDA approved ET-1R antagonist macitentan, targeting YAP and ZEB1-driven signaling, suppressed metastasis in vivo in mice. High gene expression of ET_AR/ILK/YAP/AP-1/ZEB1 was a strong predictor of poor clinical outcome in serous ovarian cancer patients, indicating the translational relevance of this signature expression.

Conclusions

This study provides novel mechanistic insights of the ET-1R-driven mediators that support the ability of HG-SOC to acquire metastatic traits which include the cooperation of YAP and ZEB1 regulatory circuit paving the way for innovative treatment of metastatic ovarian cancer.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-022-02317-1.

MicroR-542-3p can mediate ILK and further inhibit cell proliferation, migration and invasion in osteosarcoma cells

MiR-542-3p and its target gene integrin linked kinase (ILK) in human osteosarcoma together with the differentially expressed genes from osteosarcoma tissues was analyzed through bioinformatics analysis in this study. Real time quantitative polymerase chain reaction (qRT-PCR) and western blot showed that the miR-542-3p expression decreased while the ILK expression increased in the osteosarcoma tissues. The overexpressed miR-542-3p or silenced ILK restrained cell invasion, proliferation and migration and arrested cell cycle, facilitated cell apoptosis in U-2OS and 143B cells. The dual-luciferase assay confirmed the targeting relationship between miR-542-3p and ILK. MiR-542-3p overexpression inhibited osteosarcoma growth in vivo. In conclusion, miR-542-3p overexpression down-regulated its target gene ILK, promoted osteosarcoma cells apoptosis and inhibited their proliferation, migration and invasion.

Integrin-Linked Kinase Is Involved In the Proliferation and Invasion of Esophageal Squamous Cell Carcinoma

Esophageal squamous cell carcinoma (ESCC) is an aggressive type of cancer with high mortality rate in China, largely due to its high invasive and metastatic potential. The purposes of this study are to investigate the potential molecular mechanisms behind the aggressive nature of ESCC and search for new prognostic biomarkers. By employing the quantitative proteomic based strategy, we compared the proteomic profile between three ESCC samples and paired adjacent tissues. After bioinformatics analysis, four candidate proteins were validated in thirteen paired patient samples. Further validation of the key candidate, integrin-linked kinase (ILK), was carried out in one hundred patient samples. The specific inhibitor compound 22 (cpd22) was used to assess the influence of ILK to ESCC cell motility and invasiveness by applying wound-healing and transwell assay. Western blot analysis was performed to elucidate the signaling pathways involved in ILK-mediated ESCC invasion. Total 236 proteins were identified by proteomic analysis. Bioinformatics analysis suggested a key role of the collagen/integrin/ILK signaling pathway during ESCC progression. Further validation indicated that ILK is overexpressed in ESCC tissues and is correlated with poor patient prognosis. Inhibition of ILK kinase activity suppresses proliferation and blocks invasion and migration of ESCC cells. Signaling pathway analysis revealed that ILK regulates AKT phosphorylation on Ser473 but not GSK-3β on Ser9 to promote proliferation and motility of ESCC cells. In conclusion, our results indicated that ILK may play a crucial role in ESCC invasion and metastasis and may serve as a prognostic biomarker and therapeutic target for ESCC.

Oleic acid promotes cell invasion through an integrin-linked kinase signaling pathway in renal cell carcinoma

The change of fatty acid composition has been regarded as an indicator of altered lipid metabolism during human tumourigenesis, but the details are still unclear. We have previously demonstrated a monounsaturated fatty acid (MUFA) named oleic acid (OA) was involved in renal cell carcinoma (RCC) cell growth, as an extracellular signaling molecule to regulate 786-O cell proliferation via the integrin-linked kinase (ILK) pathway. In this study, we further observe the effects of OA on cell invasion of RCC and the potential mechanism by which OA worked was determined. The transwell invasion assay showed OA increased cell invasion of RCC in a dose-dependent manner. Western blotting results indicated ILK, COX-2, and MMP-9 proteins were involved for their high expressions and these effects were reversed when down-regulating the expression of ILK by special siRNA. The MMPs inhibitor GM6001 could weaken the abilities of OA on RCC cells invasion. These results suggested MUFA indeed affected cell invasion of RCC, which was depended by the regulation of ILK pathway.

[Role of TGF-β1/ILK/FSP1 signaling pathway in cyclosporin A-induced epithelialmesenchymal transition in cultured renal tubular epithelial cells]

OBJECTIVE

To explore the role of transforming growth factor-β1/integrin-linked kinase/fibroblast-specific protein 1 (TGF- β1/ILK/FSP1) signaling pathway in cyclosporine A (CsA)-induced renal tubular epithelial cell transdifferentiation.

METHODS

Rat renal tubular epithelial NRK-52E cells were induced with 1 mg/L CsA, treated with TGF-β1 inhibitor (SB431542, 10 μmol/L), or transfected with the ILK-RNAi lentiviral expression vector (ILKshRNA) or a negative control vector before CsA induction. The expressions of TGF-β1, ILK and FSP-1 mRNAs and proteins in the cells were detected using real-time PCR and Western blotting. The positive cells for α-SMA expression were detected by immunohistochemistry.

RESULTS

Compared with the blank control cells, the cells treated with CsA showed significantly increased levels of TGF-β1, ILK and FSP-1 mRNAs and proteins (P < 0.05). The expressions of TGF-β1, ILK and FSP-1 were significantly lower in TGF-β1 inhibitor group than in CsA group (P < 0.05). The levels of ILK and FSP-1 were significantly decreased after shRNA-mediated ILK silencing (P < 0.05). The number of positive cells for α-SMA was significantly lower in cells treated with SB431542 and in cells with ILK silencing than in the cells treated with CsA alone (P < 0.05).

CONCLUSIONS

The activation of TGF-β1/ILK/FSP-1 signaling pathway is an important mechanism for CsA-induced transdifferentiation in rat renal tubular epithelial cells. ILK participates in CsA-induced epithelialmesenchymal transition of renal tubular epithelial cells.

A Deregulated PI3K-AKT Signaling Pathway in Patients with Colorectal Cancer

BACKGROUND

Molecular switches in phosphatidylinositol 3-kinase (PI3K)-AKT signaling pathway may serve as potential targets for the treatment of colorectal cancer (CRC). This study aims to profile the gene alterations involved in PI3K-AKT signaling pathway in patients with CRC.

METHODS

Tumoral and matched peritumoral tissues were collected from 15 CRC patients who went routine surgery. A human PI3K-AKT signaling pathway polymerase chain reaction (PCR) array, which profiled the transcriptional changes of a total number of 84 genes involved in the PI3K-AKT pathway, was then applied to determine the gene alterations in CRC tumoral tissue with matched peritumoral tissue as a healthy control. Subsequent real-time reverse transcription PCR and western blot (WB) with different subgroups of CRC patients were then performed to further validate the array findings.

RESULTS

The PCR array identified 14 aberrantly expressed genes involved in the PI3K-AKT signaling pathway in CRC tumoral tissue, among which 12 genes, CCND1, CSNK2A1, EIF4E, EIF4EBP1, EIF4G1, FOS, GRB10, GSK3B, ILK, PTK2, PTPN11, and PHEB were significantly up-modulated (> two fold) while the remaining two, PDK1 and PIK3CG, were down-regulated (> two fold). These genes involve in the regulation of gene transcription and translation, cell cycle, and cell growth, proliferation, and differentiation. The real-time reverse transcription PCR validation agreed with the array data towards the tested genes, CCND1, EIF4E, FOS, and PIK3CG, while it failed to obtain similar result for PDK1. Interestingly, the WB analyses were further consistent with the PCR results that the protein levels of CCND1, EIF4E, and FOS were apparently up-regulated and that protein PIK3CG was down-modulated.

CONCLUSION

Taken together, the present study identified a deregulated PI3K-AKT signaling pathway in CRC patients, which might serve as therapeutic target(s).

Energy metabolism couples hepatocyte integrin-linked kinase to liver glucoregulation and postabsorptive responses of mice in an age-dependent manner

Integrin-linked kinase (ILK) is a critical intracellular signaling node for integrin receptors. Its role in liver development is complex, as ILK deletion at E10.5 (before hepatocyte differentiation) results in biochemical and morphological differences that resolve as mice age. Nevertheless, mice with ILK depleted specifically in hepatocytes are protected from the hepatic insulin resistance during obesity. Despite the potential importance of hepatocyte ILK to metabolic health, it is unknown how ILK controls hepatic metabolism or glucoregulation. The present study tested the role of ILK in hepatic metabolism and glucoregulation by deleting it specifically in hepatocytes, using a cre-lox system that begins expression at E15.5 (after initiation of hepatocyte differentiation). These mice develop the most severe morphological and glucoregulatory abnormalities at 6 wk, but these gradually resolve with age. After identifying when the deletion of ILK caused a severe metabolic phenotype, in depth studies were performed at this time point to define the metabolic programs that coordinate control of glucoregulation that are regulated by ILK. We show that 6-wk-old ILK-deficient mice have higher glucose tolerance and decreased net glycogen synthesis. Additionally, ILK was shown to be necessary for transcription of mitochondrial-related genes, oxidative metabolism, and maintenance of cellular energy status. Thus, ILK is required for maintaining hepatic transcriptional and metabolic programs that sustain oxidative metabolism, which are required for hepatic maintenance of glucose homeostasis.

Development of a Non-Coding-RNA-based EMT/CSC Inhibitory Nanomedicine for In Vivo Treatment and Monitoring of HCC

The objective of this study is to improve the overall prognosis of patients with hepatocellular carcinoma (HCC); therefore, new therapeutic methods that can be used in vivo are urgently needed. In this study, the relationship between the quantities of microRNA (miR)-125b-5p in clinical specimens and clinicopathological parameters is analyzed. A folate-conjugated nanocarrier is used to transfect miR-125b-5p in vivo and to observe the therapeutic effect on HCC. The inhibitory effect and mechanism of miR-125b-5p on hepatoma cells are also studied. Data from clinical specimens and in vitro experiments confirm that the miR-125b-5p quantity is negatively correlated with progression, and the target protein that regulates the epithelial-mesenchymal transition (EMT)/cancer stem cells (CSC) potential in HCC is STAT3. The miR-125b-5p/STAT3 axis inhibits the invasion, migration, and growth of HCC via inactivation of the wnt/β-Catenin pathway. miR-125b-5p-loaded nanomedicine effectively inhibits the EMT/CSC potential of hepatoma cells in vivo together with their magnetic resonance imaging (MRI) visualization characteristics. An HCC-therapeutic and MRI-visible nanomedicine platform that achieves noninvasive treatment effect monitoring and timely individualized treatment course adjustment is developed.

CEP55 promotes epithelial-mesenchymal transition in renal cell carcinoma through PI3K/AKT/mTOR pathway

PURPOSE

To study the detailed mechanisms of tumorigenesis and clinical outcomes of centrosomal protein 55 (CEP55) overexpression in renal cell carcinoma.

MATERIALS AND METHODS

Microarray analysis was performed to explore differentially expressed genes in five pairs of RCC tissues. Data of CEP55 expression and corresponding clinical information for 532 RCC patients of TCGA database were downloaded from cBioPortal. The expression of CEP55 in RCC tissues and cells was determined by real-time quantitative reverse transcription PCR (qRT-PCR), Western blot analysis and immunohistochemistry (IHC). Cells were transfected with siRNAs or lentivirus to regulate the expression of CEP55. The effects of CEP55 on proliferation, migration, invasion and epithelial-to-mesenchymal transition (EMT) of RCC cells were determined by MTS, migration and invasion assay and Western blot analysis.

RESULTS

CEP55, one of the most upregulated genes in microarray analysis, was overexpressed in RCC tissues and cells. CEP55 expression was significantly correlated with poor outcome including neoplasm disease stage, histologic grade and TNM status, as well as survival status of patients. In vitro experiments showed that downregulation of CEP55 could dramatically inhibit RCC cell proliferation, migration and invasion, while overexpression of CEP55 could promote these biological behaviors. We further demonstrated that CEP55 knockdown suppressed epithelial-mesenchymal transition (EMT), which was mediated via upregulation of E-cadherin and downregulation of N-cadherin and ZEB1, through PI3K/AKT/mTOR pathway. In contrast, overexpression of CEP55 could promote EMT in RCC cells via the activation of PI3K/AKT/mTOR pathway. Importantly, inhibition of PI3K/AKT/mTOR pathway reduced the effects of CEP55 on the migration, invasion and EMT of RCC cells.

CONCLUSION

Our study showed that CEP55 could promote EMT through PI3K/AKT/mTOR pathway and might be an effective prognostic marker in RCC.

ILK enhances migration and invasion abilities of human endometrial stromal cells by facilitating the epithelial-mesenchymal transition

Epithelial-mesenchymal transition (EMT) plays a significant part in the pathogenesis of endometriosis by facilitating the migration and invasion abilities of cells. Integrin-linked kinase (ILK) increases the cell migration and invasion abilities by inducing the EMT. Eutopic and control endometrial stromal cells (EuSCs and CSCs) were isolated and cultured. Cell migration and invasion abilities were detected by transwell assays. Levels of proteins were detected by Western blot. EuSCs showed higher levels of ILK, N-cadherin, vimentin and stronger migration and invasion abilities. After transfection of siRNA-ILK, E-cadherin and keratin levels were increased while N-cadherin and vimentin levels were decreased in EuSCs. Besides that, the migration and invasion abilities of EuSCs were significantly decreased after transfection of siRNA-ILK. On the contrary, levels of ILK, N-cadherin and vimentin were increased while levels of E-cadherin and keratin were decreased simultaneously after transfecting CSCs with pEGFP-C1-ILK. Simultaneously, the migration and invasion abilities of CSCs were increased after transfection of pEGFP-C1-ILK. Our study verified that high expression of ILK enhanced the migration and invasion abilities of ESCs by facilitating the EMT. Given that ILK played crucial roles in the pathogenesis of endometriosis, it may be considered as a promising targeted therapy for endometriosis.

12-HETE facilitates cell survival by activating the integrin-linked kinase/NF-κB pathway in ovarian cancer

Background

The dysfunction of cell apoptosis is an important event in the progression of cancer, and the growth of cancer cells is negatively regulated by cell apoptosis. In different types of cancers, inhibition of cellular apoptosis is often observed in the cancerous tissue, and increased resistance to apoptosis is a hallmark of cancer. Although previous studies have shown that 12-lipoxygenase (12-LOX)/12-hydroxyeicosatetraenoic acid (12-HETE) is activated and upregulated in different types of cancers, the consequences of 12-LOX/12-HETE upregulation and its precise roles in the survival of ovarian carcinoma cells are still unknown.

Methods

MTT assays, caspase activity assays, lactate dehydrogenase (LDH) assays, and Western blot analysis were the methods used in this study.

Results

In our study, we found that 12-HETE, a major metabolic product of arachidonic acid using 12-LOX catalysis, inhibited cell apoptosis in a dose-dependent manner and that the effects of 12-HETE on cell apoptosis were mediated by the integrin-linked kinase (ILK) pathway. Moreover, the downstream target of 12-HETE-activated ILK was nuclear factor kappa-B (NF-κB) in ovarian carcinoma. The inhibitory effects of 12-HETE on cell apoptosis were attenuated by the inhibition of the NF-κB pathway.

Conclusion

These results indicate that 12-HETE participates in the inhibition of cell apoptosis by activating the ILK/NF-κB pathway, implying an important underlying mechanism that promotes the survival of ovarian cancer cells.

Graphene and graphene oxide as a solid matrix for extraction of membrane and membrane-associated proteins

The extraction of membrane proteins remain a challenge due to innate hydrophobicity, dynamic discrepancy, and restrain effect of membrane lipids. Nanomaterials with high surface area have competency of hydrophobic-hydrophobic lipid interactions. It is shown here that both graphene and graphene oxide dissolved in solubilization buffer are viable sorbents for efficient extraction of membrane proteins. LC-MS/MS analysis further revealed that graphene (50-200 nm) and graphene oxide (50-200 nm) can enrich more kinds of membrane proteins than a commercially available kit. Graphene was further applied to the enrichment of membrane proteins of normal cells as well as cancer cells, and 1079 and 872 proteins were identified, respectively, among which 56.5% and 60.5% were membrane proteins. In particular, 241 proteins were significantly regulated in cancer cells. Gene expression of 15 proteins was verified by qRT-PCR, and 4 of them were further quantified by immunoassay. These data collectively demonstrate that graphene has great potential to improve membrane protein extractions and thus can serve downstream cancer proteomics. Graphical abstract Two dimensional carbon nanomaterials, including graphene and graphene oxide, were employed as solid matrix to avoid lipid bilayer interference and enhance the extraction efficiency of membrane and membrane associated proteins. The strategy will benefit downstream membrane proteomics analysis.

Integrin linked kinase regulates syncytialization of BeWo trophoblast cells

During placental development, mononuclear villous cytotrophoblast cells differentiate and fuse with the overlying syncytiotrophoblast. This process requires the dissolution of E-cadherin (CDH1)-containing adherens junctions in cytotrophoblast. Integrin linked kinase (ILK) can downregulate CDH1 through poly (ADP-ribose) polymerase 1 (PARP1) and Snail-1 (SNAI1) during epithelial-mesenchymal transition. ILK is known to be expressed in cytotrophoblast; thus, the role of a potential ILK-PARP1-SNAI1 pathway in aiding trophoblast syncytialization via the downregulation of CDH1 was examined. The spatiotemporal expression of PARP1, SNAI1, and CDH1 were determined in first and early second trimester chorionic villi, term villi, and BeWo cells by immunofluorescence analysis. PARP1 and SNAI1 were highly detectable in villous cytotrophoblast nuclei of human chorionic villi and SNAI1 expression, in particular, also persisted in syncytiotrophoblast. In BeWo cells undergoing syncytialization, PARP1 and SNAI1 increasingly localized to cell nuclei in correlation with decreased CDH1 expression. Using luciferase reporter assays, it was determined that PARP1 and SNAI1 promoter activities were significantly higher in BeWo cells during syncytialization compared to the activities in proliferating cells. Overexpression of wild type or constitutively active ILK also resulted in significantly increased PARP1 and SNAI1 promoter activities while dominant negative ILK overexpression significantly reduced promoter activities. Lastly, siRNA-mediated depletion of ILK expression in BeWo cells undergoing syncytialization resulted in significantly reduced SNAI1 expression and a significant reduction in the incidence of syncytialization correlating with increased CDH1 expression. These results demonstrate that ILK aids trophoblast syncytialization via the downregulation of CDH1, perhaps through an ILK-PARP1-SNAI1 pathway.

Transforming growth factor-β1 signaling promotes epithelial-mesenchymal transition-like phenomena, cell motility, and cell invasion in synovial sarcoma cells

The epithelial-to-mesenchymal transition (EMT) and the reverse process (the mesenchymal-to-epithelial transition [MET]) have been shown to be associated with tumor cell invasion and metastasis in different carcinomas. The EMT and MET have recently been shown to play a key role in the pathogenic processes of sarcomas, which are completely different from those of carcinomas. However, the definitive roles of the EMT in the tumorigenesis of synovial sarcomas remain unknown. Here, we explored whether transforming growth factor (TGF)-β signaling, an important oncogenic event in synovial sarcoma, modulates tumor cell characteristics related to the EMT, such as cell adhesion, migration, invasion, and proliferation. Interestingly, we found that TGF-β1 induced tumor cell activation, resulting in a tendency to aggregate and biphasic-like features. TGF-β1 also caused downregulation of E-cadherin and subsequent upregulation of N-cadherin, Snail, and Slug, which are responsible for EMT-like phenomena and increased cell motility and invasion. To further investigate the roles of TGF-β1 in the EMT, we established a SW982 cell line with stable TGF-β1 inhibition viaSB431542.These cells exhibited significantly decreased motility, migration, and proliferation (P = 0.001). Taken together, our data demonstrated that alterations in the TGF-β1/Smad signaling pathway could regulate the expression of EMT-related factors and the EMT process, resulting in changes in tumor cell invasion, migration, and proliferation in synovial sarcoma cells. These results may provide a important insights into therapeutic interventions and contribute to the present understanding of tumor progression in patients.

Epithelial to Mesenchymal Transition in Renal Cell Carcinoma: Implications for Cancer Therapy

Epithelial-to-mesenchymal transition (EMT) is a developmentally vital reversible process by which fully differentiated cells lose their epithelial features and acquire a migratory mesenchymal phenotype. EMT contributes to the metastatic potential of tumors. The expression profile and other biological properties of EMT suggest potential targets for cancer therapy, including in renal-cell carcinoma (RCC). The preclinical and clinical results have substantiated the promises that dysregulated elements leading to EMT can be a potential target in RCC patients. In this study, we illustrated the pathogenic and prognostic role of EMT in RCC. In addition, we reconstructed, by literature analysis, the different pathways implicated in the EMT process, thus supporting the rational for future EMT-directed therapeutic approaches for RCC patients.

Trichostatin A Enhances the Apoptotic Potential of Palladium Nanoparticles in Human Cervical Cancer Cells

Cervical cancer ranks seventh overall among all types of cancer in women. Although several treatments, including radiation, surgery and chemotherapy, are available to eradicate or reduce the size of cancer, many cancers eventually relapse. Thus, it is essential to identify possible alternative therapeutic approaches for cancer. We sought to identify alternative and effective therapeutic approaches, by first synthesizing palladium nanoparticles (PdNPs), using a novel biomolecule called saponin. The synthesized PdNPs were characterized by several analytical techniques. They were significantly spherical in shape, with an average size of 5 nm. Recently, PdNPs gained much interest in various therapies of cancer cells. Similarly, histone deacetylase inhibitors are known to play a vital role in anti-proliferative activity, gene expression, cell cycle arrest, differentiation and apoptosis in various cancer cells. Therefore, we selected trichostatin A (TSA) and PdNPs and studied their combined effect on apoptosis in cervical cancer cells. Cells treated with either TSA or PdNPs showed a dose-dependent effect on cell viability. The combinatorial effect, tested with 50 nM TSA and 50 nMPdNPs, had a more dramatic inhibitory effect on cell viability, than either TSA or PdNPs alone. The combination of TSA and PdNPs had a more pronounced effect on cytotoxicity, oxidative stress, mitochondrial membrane potential (MMP), caspase-3/9 activity and expression of pro- and anti-apoptotic genes. Our data show a strong synergistic interaction between TSA and PdNPs in cervical cancer cells. The combinatorial treatment increased the therapeutic potential and demonstrated relevant targeted therapy for cervical cancer. Furthermore, we provide the first evidence for the combinatory effect and cytotoxicity mechanism of TSA and PdNPs in cervical cancer cells.

Relationship between integrin and epithelial-mesenchymal transition during invasion and metastasis of digestive system carcinomas

Invasion and metastasis are distinctive features of malignant tumors of the digestive system. Studies show that epithelial-mesenchymal transition (EMT), a conversion process with the loss of epithelial cell features and the gain of mesenchymal phenotype, has been recognized as a key element of invasion and metastasis of malignancies. When EMT occurs, down-regulation of E-cadherins and loss of adhesion in extracellular matrix play critical roles, which are regarded as important indicators in the assessment of EMT. Integrin, one of cell adhesion molecule families, is involved in EMT directly or indirectly through mediating either adhesion among cells and between cells and extracellular matrix, or signal pathways. This paper summarizes the relationship between EMT and integrin.

Gene set enrichment analysis and ingenuity pathway analysis of metastatic clear cell renal cell carcinoma cell line

In recent years, genome-wide RNA expression analysis has become a routine tool that offers a great opportunity to study and understand the key role of genes that contribute to carcinogenesis. Various microarray platforms and statistical approaches can be used to identify genes that might serve as prognostic biomarkers and be developed as antitumor therapies in the future. Metastatic renal cell carcinoma (mRCC) is a serious, life-threatening disease, and there are few treatment options for patients. In this study, we performed one-color microarray gene expression (4×44K) analysis of the mRCC cell line Caki-1 and the healthy kidney cell line ASE-5063. A total of 1,921 genes were differentially expressed in the Caki-1 cell line (1,023 upregulated and 898 downregulated). Gene Set Enrichment Analysis (GSEA) and Ingenuity Pathway Analysis (IPA) approaches were used to analyze the differential-expression data. The objective of this research was to identify complex biological changes that occur during metastatic development using Caki-1 as a model mRCC cell line. Our data suggest that there are multiple deregulated pathways associated with metastatic clear cell renal cell carcinoma (mccRCC), including integrin-linked kinase (ILK) signaling, leukocyte extravasation signaling, IGF-I signaling, CXCR4 signaling, and phosphoinositol 3-kinase/AKT/mammalian target of rapamycin signaling. The IPA upstream analysis predicted top transcriptional regulators that are either activated or inhibited, such as estrogen receptors, TP53, KDM5B, SPDEF, and CDKN1A. The GSEA approach was used to further confirm enriched pathway data following IPA.

Emodin Inhibits Migration and Invasion of Human Endometrial Stromal Cells by Facilitating the Mesenchymal-Epithelial Transition Through Targeting ILK

OBJECTIVE

To determine whether emodin facilitates the mesenchymal-epithelial transition (MET) of endometrial stromal cells (ESCs) as well as to explore the mechanism through which emodin favored the MET of ESCs.

METHODS

Cell viability was tested by methyl thiazolyl tetrazolium assay. Cell migration and invasion abilities were detected by transwell assays. Levels of integrin-linked kinase (ILK) and epithelial-mesenchymal transition (EMT)-related proteins were detected by Western blot.

RESULTS

Upregulated ILK and increased abilities of migration and invasion were confirmed in the eutopic and ectopic ESCs (EuSCs and EcSCs), especially in the EcSCs. After treated with emodin, the expression of ILK was statistically downregulated in EcSCs, resulting in the MET and decreased migration and invasion abilities of EcSCs. Additionally, silencing of the ILK gene in EcSCs also achieved the above-mentioned effects, which were strengthened by emodin. Furthermore, exogenous expression of ILK in control ESCs (CSCs) resulted in the EMT and increased abilities of migration and invasion of CSCs, which can be abrogated by emodin. Besides, exogenous expression of ILK also abrogated the effects of emodin on CSCs.

CONCLUSION

Emodin inhibits the migration and invasion abilities of human ESCs by facilitating the MET through targeting ILK.

Distinct routes to metastasis: plasticity-dependent and plasticity-independent pathways

The cascade that culminates in macrometastases is thought to be mediated by phenotypic plasticity, including epithelial–mesenchymal and mesenchymal–epithelial transitions (EMT and MET). Although there is substantial support for the role of EMT in driving cancer cell invasion and dissemination, much less is known about the importance of MET in the later steps of metastatic colonization. We created novel reporters, which integrate transcriptional and post-transcriptional regulation, to test whether MET is required for metastasis in multiple in vivo cancer models. In a model of carcinosarcoma, metastasis occurred via an MET-dependent pathway; however, in two prostate carcinoma models, metastatic colonization was MET independent. Our results provide evidence for both MET-dependent and MET-independent metastatic pathways.

Integrin-linked kinase affects signaling pathways and migration in thyroid cancer cells and is a potential therapeutic target

BACKGROUND

Integrin-linked kinase (ILK) is a serine-threonine kinase that regulates interactions between the cell and the extracellular matrix. In many cancers, overexpression of ILK leads to increased cell proliferation, motility, and invasion. We hypothesized that ILK functions as a regulator of viability and migration in thyroid cancer cells.

METHODS

Eleven human thyroid cancer cell lines were screened for ILK protein expression. The cell lines with the greatest expression were treated with either ILK small interfering RNA (siRNA) or a novel ILK inhibitor, T315, and the effects were evaluated via Western blot and migration assay. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide assays were performed to assess cell viability.

RESULTS

siRNA against ILK decreased phosphorylation of downstream effectors Akt and MLC, as well as decreased migration. Treatment with T315 showed a dose-related decrease in both Akt and MLC phosphorylation, as well as decreased migration. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide assays showed T315 to have an half maximal inhibitory concentration of less than 1 μM in cell lines with high ILK expression.

CONCLUSION

ILK is expressed differentially in thyroid cancer cell lines. Both ILK siRNA and T315 inhibit motility of thyroid cancer cell lines, and T315 is shown to be cytotoxic at low concentrations. Altogether, our study suggests that ILK may represent an important kinase in aggressive thyroid cancers.