Salinomycin attenuates liver cancer stem cell motility by enhancing cell stiffness and increasing F-actin formation via the FAK-ERK1/2 signalling pathway

Single-cell RNA sequencing reveals ECM remodeling-tumor stiffness-FAK as a key driver of vestibular schwannoma progression

Vestibular schwannoma (VS), characterized by the absence of merlin expression, is the most prevalent benign tumor located at the cerebellopontine angle, lacking approved pharmaceutical interventions except for off-label utilization of bevacizumab. The role of Tumor stiffness-Focal adhesion kinase (FAK) activation in fueling tumor progression is well-established, with merlin deficiency serving as a biomarker for tumor sensitivity to FAK inhibitors. In this context, we investigated whether Tumor stiffness-FAK contributes to VS progression. Single-cell RNA sequencing revealed associations between VS progression and gene sets related to "Response to mechanical stimulus" and "Neurotrophin signaling pathway". Histological studies indicated a potential involvement of neurotrophins in early stages of VS tumorigenesis, while enhanced Extracellular matrix (ECM) remodeling-Tumor stiffness-FAK signaling accompanies later stages of VS progression. In vitro experiments demonstrated that elevated matrix stiffness induces cytoskeletal remodeling, cell proliferation, and metalloproteinase expression in VS cells by activating FAK. Conversely, FAK inhibition diminishes these effects. Collectively, this study suggests that ECM remodeling-Tumor stiffness contributes to VS progression via FAK activation, positioning FAK as a promising therapeutic target in treating VS.

Biomechanics in the tumor microenvironment: from biological functions to potential clinical applications

Immune checkpoint therapies have spearheaded drug innovation over the last decade, propelling cancer treatments toward a new era of precision therapies. Nonetheless, the challenges of low response rates and prevalent drug resistance underscore the imperative for a deeper understanding of the tumor microenvironment (TME) and the pursuit of novel targets. Recent findings have revealed the profound impacts of biomechanical forces within the tumor microenvironment on immune surveillance and tumor progression in both murine models and clinical settings. Furthermore, the pharmacological or genetic manipulation of mechanical checkpoints, such as PIEZO1, DDR1, YAP/TAZ, and TRPV4, has shown remarkable potential in immune activation and eradication of tumors. In this review, we delved into the underlying biomechanical mechanisms and the resulting intricate biological meaning in the TME, focusing mainly on the extracellular matrix, the stiffness of cancer cells, and immune synapses. We also summarized the methodologies employed for biomechanical research and the potential clinical translation derived from current evidence. This comprehensive review of biomechanics will enhance the understanding of the functional role of biomechanical forces and provide basic knowledge for the discovery of novel therapeutic targets.

Salinomycin attenuates kidney fibrosis and inflammation in mice with unilateral ureteral obstruction

Renal fibrosis is a crucial pathological feature in chronic kidney disease (CKD), resulting in the gradual decline of renal function. Salinomycin is an antibiotic discovered from Streptomyces albus that also regulates the fates of cells. However, its potential in kidney fibrosis remains elusive. In this study, salinomycin was administrated to a renal fibrosis mouse model with unilateral ureteral obstruction (UUO) and a kidney fibroblast cell line (NRK-49F cells) treated with transforming growth factor-β1 (TGF-β1). In vivo, salinomycin treatment attenuated tubulointerstitial fibrosis, as evidenced by Gomori's trichrome staining, in line with decreased mRNA and protein expressions of fibronectin, collagen type I/IV, in the UUO kidneys. Furthermore, inflammasome mRNA level in the kidney with UUO was also suppressed by salinomycin. In vitro, salinomycin administration impeded the upregulation of fibronectin, collagen type I/IV, and ⍺-smooth muscle actin in NRK-49F cells stimulated with TGF-β1. Importantly, the inhibitory properties of salinomycin were correlated with reduction of Smad2/3 and MAPK-p38 phosphorylation. Together, our data indicate salinomycin as a potential medication to counteract renal fibrosis in patients with CKD.

STAT3 mediates ECM stiffness-dependent progression in ovarian cancer

The treatment of ovarian cancer remains a medical challenge and its malignant progression is connected with obvious changes in both tissue and cell stiffness. However, the accurate mechanical-responsive molecules and mechanism remains unclear in ovarian cancer. Based on our previous results combined with the crucial regulatory role of STAT3 in the malignant progression of various cancer types, we want to investigate the relationship between STAT3 and matrix stiffness in ovarian cancer and further explore the potential mechanisms. Collagen-coated polyacrylamide gels (1, 6, and 60 kPa) were prepared to mimic soft or hard matrix stiffness. Western blotting, qRT-PCR, flow cytometry, IHC, EdU assays, and TEM were used to evaluate the effect of STAT3 in vitro under different matrix stiffnesses. Furthermore, a BALB/c nude mouse model was established to assess the relationship in vivo. Our results confirmed the differential expression of STAT3/p-STAT3 not only in normal and malignant ovarian tissues but also under different matrix stiffnesses. Furthermore, we verified that STAT3 was a mechanically responsive gene both in vitro and in vivo, and the mechanical response was carried out by altering the migration-related molecules (TNFAIP1) and adhesion-related molecules (LPXN, CNN3). The novel findings suggest that STAT3, a potential therapeutic target for clinical diagnosis and treatment, is a mechanically responsive gene that responds to matrix stiffness, particularly regulation in migration and adhesion in the progression of ovarian cancer.

Sustained intestinal epithelial monolayer wound closure after transient application of a FAK-activating small molecule

M64HCl, which has drug-like properties, is a water-soluble Focal Adhesion Kinase (FAK) activator that promotes murine mucosal healing after ischemic or NSAID-induced injury. Since M64HCl has a short plasma half-life in vivo (less than two hours), it has been administered as a continuous infusion with osmotic minipumps in previous animal studies. However, the effects of more transient exposure to M64HCl on monolayer wound closure remained unclear. Herein, we compared the effects of shorter M64HCl treatment in vitro to continuous treatment for 24 hours on monolayer wound closure. We then investigated how long FAK activation and downstream ERK1/2 activation persist after two hours of M64HCl treatment in Caco-2 cells. M64HCl concentrations immediately after washing measured by mass spectrometry confirmed that M64HCl had been completely removed from the medium while intracellular concentrations had been reduced by 95%. Three-hour and four-hour M64HCl (100 nM) treatment promoted epithelial sheet migration over 24 hours similar to continuous 24-hour exposure. 100nM M64HCl did not increase cell number. Exposing cells twice with 2-hr exposures of M64HCl during a 24-hour period had a similar effect. Both FAK inhibitor PF-573228 (10 μM) and ERK kinase (MEK) inhibitor PD98059 (20 μM) reduced basal wound closure in the absence of M64HCl, and each completely prevented any stimulation of wound closure by M64HCl. Rho kinase inhibitor Y-27632 (20 μM) stimulated Caco-2 monolayer wound closure but no further increase was seen with M64HCl in the presence of Y-27632. M64HCl (100 nM) treatment for 3 hours stimulated Rho kinase activity. M64HCl decreased F-actin in Caco-2 cells. Furthermore, a two-hour treatment with M64HCl (100 nM) stimulated sustained FAK activation and ERK1/2 activation for up to 16 and hours 24 hours, respectively. These results suggest that transient M64HCl treatment promotes prolonged intestinal epithelial monolayer wound closure by stimulating sustained activation of the FAK/ERK1/2 pathway. Such molecules may be useful to promote gastrointestinal mucosal repair even with a relatively short half-life.

Salinomycin and IR780-loaded upconversion nanoparticles influence biological behavior of liver cancer stem cells by persistently activating the MAPK signaling pathway

The combination of chemotherapy and phototherapy has emerged as a promising therapeutic approach for enhancing the efficacy of cancer treatment and mitigating drug resistance. Salinomycin (SAL), a polyether antibiotic, exhibits potent cytotoxicity against chemotherapy-resistant cancer cells. IR780 iodide, a novel photosensitive reagent with excellent near-infrared (NIR) light absorption and photothermal conversion abilities, is suitable for use in photothermal therapy for cancers. However, both SAL and IR780 exhibit hydrophobic properties that limit their clinical applicability. Upconversion nanoparticles (UCNPs) are an emerging class of fluorescent probe materials capable of emitting high-energy photons upon excitation by low-energy NIR light. The UCNPs not only function as nanocarriers for drug delivery but also serve as light transducers to activate photosensitizers for deep-tissue photodynamic therapy. Here, to enhance the targeting and bioavailability of hydrophobic drugs in liver cancer stem cells (LCSCs), we employ distearoyl phosphorethanolamine-polyethylene glycol (DSPE-PEG) to encapsulate SAL and IR780 on the surface of UCNPs. Cell viability was evaluated using the CCK-8 assay. Cell migration was assessed by the Transwell Boyden Chamber. The activation of the mitogen-activated protein kinase (MAPK) signaling pathway was measured via western blot. The results demonstrated successful loading of both IR780 and SAL onto the UCNPs, and the SAL and IR780-loaded UCNPs (UISP) exhibited a robust photothermal effect under NIR light irradiation. The UISP effectively inhibited the viability of HCCLM3 and LCSCs. Under NIR light irradiation, the UISP further suppressed HCCLM3 viability but had no impact on LCSC viability; however, it could further inhibit LCSC migration. Meanwhile, under NIR light irradiation, the UISP persistently activated the MAPK pathway more significantly in LCSCs. These findings suggest that exposure to NIR light results in persistent activation of the MAPK pathway by UISP, thereby influencing the biological behavior of LCSCs and enhancing their therapeutic efficacy against liver cancer.

Inhibition of Wnt/β-catenin signaling by monensin in cervical cancer

The challenging clinical outcomes associated with advanced cervical cancer underscore the need for a novel therapeutic approach. Monensin, a polyether antibiotic, has recently emerged as a promising candidate with anti-cancer properties. In line with these ongoing efforts, our study presents compelling evidence of monensin's potent efficacy in cervical cancer. Monensin exerts a pronounced inhibitory impact on proliferation and anchorage-independent growth. Additionally, monensin significantly inhibited cervical cancer growth in vivo without causing any discernible toxicity in mice. Mechanism studies show that monensin's anti-cervical cancer activity can be attributed to its capacity to inhibit the Wnt/β-catenin pathway, rather than inducing oxidative stress. Monensin effectively reduces both the levels and activity of β-catenin, and we identify Akt, rather than CK1, as the key player involved in monensin-mediated Wnt/β-catenin inhibition. Rescue studies using Wnt activator and β-catenin-overexpressing cells confirmed that β-catenin inhibition is the mechanism of monensin's action. As expected, cervical cancer cells exhibiting heightened Wnt/β-catenin activity display increased sensitivity to monensin treatment. In conclusion, our findings provide pre-clinical evidence that supports further exploration of monensin's potential for repurposing in cervical cancer therapy, particularly for patients exhibiting aberrant Wnt/β-catenin activation.

DNA methyltransferase 1 deficiency improves macrophage motility and wound healing by ameliorating cholesterol accumulation

Healing of the cutaneous wound requires macrophage recruitment at the sites of injury, where chemotactic migration of macrophages toward the wound is regulated by local inflammation. Recent studies suggest a positive contribution of DNA methyltransferase 1 (Dnmt1) to macrophage pro-informatory responses; however, its role in regulating macrophage motility remains unknown. In this study, myeloid-specific depletion of Dnmt1 in mice promoted cutaneous wound healing and de-suppressed the lipopolysaccharides (LPS)-inhibited macrophage motility. Dnmt1 inhibition in macrophages eliminated the LPS-stimulated changes in cellular mechanical properties in terms of elasticity and viscoelasticity. LPS increased the cellular accumulation of cholesterol in a Dnmt1-depedent manner; cholesterol content determined cellular stiffness and motility. Lipidomic analysis indicated that Dnmt1 inhibition altered the cellular lipid homeostasis, probably through down-regulating the expression of cluster of differentiation 36 CD36 (facilitating lipid influx) and up-regulating the expression of ATP-binding cassette transporter ABCA1 (mediating lipid efflux) and sterol O-acyltransferase 1 SOAT1 (also named ACAT1, catalyzing the esterification of cholesterol). Our study revealed a Dnmt1-dependent epigenetic mechanism in the control of macrophage mechanical properties and the related chemotactic motility, indicating Dnmt1 as both a marker of diseases and a potential target of therapeutic intervention for wound healing.

Dinactin: A New Antitumor Antibiotic with Cell Cycle Progression and Cancer Stemness Inhibiting Activities in Lung Cancer

Lung cancer, especially non-small cell lung cancer (NSCLC), is one of the most complex diseases, despite the existence of effective treatments such as chemotherapy and immunotherapy. Since cancer stem cells (CSCs) are responsible for chemo- and radio-resistance, metastasis, and cancer recurrence, finding new therapeutic targets for CSCs is critical. Dinactin is a natural secondary metabolite produced by microorganisms. Recently, dinactin has been revealed as a promising antitumor antibiotic via various mechanisms. However, the evidence relating to cell cycle progression regulation is constrained, and effects on cancer stemness have not been elucidated. Therefore, the aim of this study is to evaluate the new function of dinactin in anti-NSCLC proliferation, focusing on cell cycle progression and cancer stemness properties in Lu99 and A549 cells. Flow cytometry and immunoblotting analyses revealed that 0.1-1 µM of dinactin suppresses cell growth through induction of the G₀/G₁ phase associated with down-regulation of cyclins A, B, and D3, and cdk2 protein expression. The tumor-sphere forming capacity was used to assess the effect of dinactin on the cancer stemness potential in NSCLC cells. At a concentration of 1 nM, dinactin reduced both the number and size of the tumor-spheres. The quantitative RT-PCR analyses indicated that dinactin suppressed sphere formation by significantly reducing expression of CSC markers (i.e., ALDH1A1, Nanog, Oct4, and Sox2) in Lu99 cells. Consequently, dinactin could be a promising strategy for NSCLC therapy targeting CSCs.

Cell senescence alters responses of porcine trabecular meshwork cells to shear stress

Mechanical microenvironment and cellular senescence of trabecular meshwork cells (TMCs) are suspected to play a vital role in primary open-angle glaucoma pathogenesis. However, central questions remain about the effect of shear stress on TMCs and how aging affects this process. We have investigated the effect of shear stress on the biomechanical properties and extracellular matrix regulation of normal and senescent TMCs. We found a more significant promotion of Fctin formation, a more obvious realignment of F-actin fibers, and a more remarkable increase in the stiffness of normal cells in response to the shear stress, in comparison with that of senescent cells. Further, as compared to normal cells, senescent cells show a reduced extracellular matrix turnover after shear stress stimulation, which might be attributed to the different phosphorylation levels of the extracellular signal-regulated kinase. Our results suggest that TMCs are able to sense and respond to the shear stress and cellular senescence undermines the mechanobiological response, which may lead to progressive failure of cellular TM function with age.

Functional and clinical characteristics of focal adhesion kinases in cancer progression

Focal adhesion kinase (FAK) is a non-receptor tyrosine kinase and an adaptor protein that primarily regulates adhesion signaling and cell migration. FAK promotes cell survival in response to stress. Increasing evidence has shown that at the pathological level, FAK is highly expressed in multiple tumors in several systems (including lung, liver, gastric, and colorectal cancers) and correlates with tumor aggressiveness and patient prognosis. At the molecular level, FAK promotes tumor progression mainly by altering survival signals, invasive capacity, epithelial-mesenchymal transition, the tumor microenvironment, the Warburg effect, and stemness of tumor cells. Many effective drugs have been developed based on the comprehensive role of FAK in tumor cells. In addition, its potential as a tumor marker cannot be ignored. Here, we discuss the pathological and pre-clinical evidence of the role of FAK in cancer development; we hope that these findings will assist in FAK-based clinical studies.

Molecular determinants of intrinsic cellular stiffness in health and disease

In recent years, the role of intrinsic biophysical features, especially cellular stiffness, in diverse cellular and disease processes is being increasingly recognized. New high throughput techniques for the quantification of cellular stiffness facilitate the study of their roles in health and diseases. In this review, we summarized recent discovery about how cellular stiffness is involved in cell stemness, tumorigenesis, and blood diseases. In addition, we review the molecular mechanisms underlying the gene regulation of cellular stiffness in health and disease progression. Finally, we discussed the current understanding on how the cytoskeleton structure and the regulation of these genes contribute to cellular stiffness, highlighting where the field of cellular stiffness is headed.

Novel perspectives on the therapeutic role of cryptotanshinone in the management of stem cell behaviors for high-incidence diseases

Cryptotanshinone (CTS), a diterpenoid quinone, is found mostly in Salvia miltiorrhiza Bunge (S. miltiorrhiza) and plays a crucial role in many cellular processes, such as cell proliferation/self-renewal, differentiation and apoptosis. In particular, CTS’s profound physiological impact on various stem cell populations and their maintenance and fate determination could improve the efficiency and accuracy of stem cell therapy for high-incidence disease. However, as much promise CTS holds, these CTS-mediated processes are complex and multifactorial and many of the underlying mechanisms as well as their clinical significance for high-incidence diseases are not yet fully understood. This review aims to shed light on the impact and mechanisms of CTS on the actions of diverse stem cells and the involvement of CTS in the many processes of stem cell behavior and provide new insights for the application of CTS and stem cell therapy in treating high-incidence diseases.

Biomechanics of cancer stem cells

Cancer stem cells (CSCs) have been believed to be one driving force for tumor progression and drug resistance. Despite the significance of biochemical signaling in malignancy, highly malignant tumor cells or CSCs exhibit lower cellular stiffness than weakly malignant cells or non-CSCs, which are softer than their healthy counterparts, suggesting the inverse correlation between cell stiffness and malignancy. Recent years have witnessed the rapid accumulation of evidence illustrating the reciprocity between cell cytoskeleton/mechanics and CSC functions and the potential of cellular stiffness for specific targeting of CSCs. However, a systematic understanding of tumor cell mechanics and their role in CSCs and tumor progression is still lacking. The present review summarizes the recent progress in the alterations of tumor cell cytoskeleton and stiffness at different stages of tumor progression and recapitulates the relationship between cellular stiffness and CSC functions. The altered cell mechanics may mediate the mechanoadaptive responses that possibly empower CSCs to survive and thrive during metastasis. Furthermore, we highlight the possible impact of tumor cell mechanics on CSC malignancy, which may potentiate low cell stiffness as a mechanical marker for CSC targeting.

Shikonin inhibits the proliferation of cervical cancer cells via FAK/AKT/GSK3β signalling

Cervical cancer is one of the most lethal malignancies of the female reproductive system. Shikonin, a naphthoquinone pigment extracted from the traditional medicinal herb, Lithospermum erythrorhizon, has been demonstrated to exert significant inhibitory effects on a variety of tumours in vitro and in vivo. In the present study, the effects of shikonin on cervical cancer and the underlying mechanisms were investigated. The effects of shikonin on the viability on HeLa and SiHa cervical cancer cells was examined using cell counting kit (CCK-8) and colony formation assays. Immunofluorescence assay was performed to detect the levels of the proliferation-related protein, Ki67. Western blot analysis was utilized to measure the phosphorylated and total expression levels of proteins, including focal adhesion kinase (FAK), AKT, and glycogen synthase kinase 3β (GSK3β). Cell migration was determined by using wound healing assay. Metastasis-associated 1 (MTA1), TGFβ1 and VEGF mRNA expression levels were determined using reverse transcription-quantitative PCR. It was demonstrated that, shikonin inhibited cervical cancer cell proliferation and migration. The data of the present study revealed that shikonin inhibited the proliferation of HeLa and SiHa cells in a concentration- and time-dependent manner. Mechanistically, shikonin blocked the proliferation of cervical cancer cells by downregulating the phosphorylation of FAK, AKT and GSK3β induced by EGF. In addition, shikonin significantly suppressed cell migration and reduced the expression of migration-related proteins, including MTA1, TGFβ1 and VEGF. On the whole, the present study demonstrates that shikonin may exert an inhibitory effect on the cervical cancer cell proliferation and migration through the FAK/AKT/GSK3β signaling pathway. These findings suggest that shikonin may function as a potential therapeutic drug for the treatment of cervical cancer.

Positive regulation of MarR-type regulator slnO and improving salinomycin production of Streptomyces albus by multiple transcriptional regulations

The purpose of this study is to explore the function of MarR-family regulator slnO. In addition, the high-yield strain of salinomycin was constructed by using combined regulation strategies. Firstly the slnO gene over-expression strain (GO) was constructed in Streptomyces albus. Compared to wild type (WT) strain，salinomycin production in GO strain was increased about 28%. Electrophoretic mobility gel shift assays (EMSAs) confirmed that SlnO protein can bind specifically to the intergenic region of slnN-slnO, slnQ-slnA1 and slnF-slnT. qRT-PCR experiments also showed that slnA1, slnF, and slnT1 were significantly up-regulated, while the expression level of the slnN gene was down-regulated in GO strain. Secondly, slnN gene deletion strain (slnNDM) was used as the starting strain, and the pathway specific gene slnR in salinomycin gene cluster was over expressed in slnNDM. The new strain was named ZJUS01. The yield of salinomycin in ZJUS01 strain was 25% and 56% higher than that in slnNDM strain and WT strain. Above results indicate that the slnO gene has a positive regulation effect on the biosynthesis of salinomycin. Meanwhile, the yield of salinomycin could be greatly increased by manipulating multiple transcriptional regulations.

Pre-clinical evidence that salinomycin is active against retinoblastoma via inducing mitochondrial dysfunction, oxidative damage and AMPK activation

The poor outcomes in retinoblastoma necessitate new treatments. Salinomycin is an attractive candidate, and has demonstrated selective anti-cancer properties in different cancer types. This work addressed the efficacy of salinomycin in retinoblastoma models and probe the associated mechanisms. Cellular functional assays were conducted to determine the effects salinomycin in vitro. Xenograft retinoblastoma mouse model was established to investigate the efficacy of salinomycin in vivo. Biochemical assays were conducted to analyze the mechanism of salinomycin's action focusing on mitochondrial functions, energy reduction-related signaling pathways. Salinomycin has positive effects towards retinoblastoma cells regardless of heterogeneity through suppressing growth and inducing apoptosis. Salinomycin also specifically inhibits cells displaying stemness and highly invasive phenotypes. Using retinoblastoma xenograft mouse model, we show that salinomycin at non-toxic dose effectively inhibits growth and induces apoptosis. Mechanistic studies show that salinomycin inhibits mitochondrial respiration via specifically suppressing complex I and II activities, reduces mitochondrial membrane potential and decreases energy reduction, followed by induction of oxidative stress and damage, AMPK activation and mTOR inhibition. Our study highlights that adding salinomycin to the existing treatment armamentarium for retinoblastoma is beneficial.

Synthesis and evaluation of FAK inhibitors with a 5-fluoro-7H-pyrrolo[2,3-d]pyrimidine scaffold as anti-hepatocellular carcinoma agents

Focal adhesion kinase (FAK) is a ubiquitous intracellular non-receptor tyrosine kinase, which is involved in multiple cellular functions, including cell adhesion, migration, invasion, survival, and angiogenesis. In this study, a series of 7H-pyrrolo[2,3-d]pyrimidines were designed and synthesized according to the E-pharmacophores generated by docking a library of 667 fragments into the ATP pocket of the co-crystal complex of FAK and PF-562271 (PDB ID: 3BZ3). The 5-fluoro-7H-pyrrolo[2,3-d]pyrimidine derivatives demonstrated excellent activity against FAK and the cell lines SMMC7721 and YY8103. 2-((2-((3-(Acetamidomethyl)phenyl)amino)-5-fluoro-7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)-N-methylbenzamide (16c) was selected for further bioactivity evaluations in vivo, including preliminary pharmacokinetic profiling in rats and toxicity assays in mice, and tumor growth inhibition studies in a xenograft tumor model. The results showed that 16c did not affect the body weight gain of the animals up to a dose of 200 mg/kg, and significantly inhibited tumor growth with a tumor growth inhibition rate of 78.6% compared with the negative control group. Furthermore, phosphoantibody array analyses of a sample of the tumor suggested that 16c inhibited the malignant proliferation of hepatocellular carcinoma (HCC) cells through decreasing the phosphorylation in the FAK cascade.

Stiffening of Cancer Cell Membranes Is a Key Biophysical Mechanism of Primary and Tertiary Cancer Prevention with Green Tea Polyphenols

Over the past 30 years, research of green tea polyphenols, especially (-)-epigallocatechin gallate (EGCG), has revealed that consumption of green tea is a practical and effective primary cancer prevention method for the general population. More recently, we believe that green tea polyphenols are beneficial for tertiary cancer prevention using green tea alone or combined with anticancer drugs because EGCG has the potential to inhibit metastatic progression and stemness, and enhance antitumor immunity. In an effort to identify a common underlying mechanism responsible for EGCG's multifunctional effects on various molecular targets, we studied the biophysical effects of EGCG on cell stiffness using atomic force microscopy. We found that EGCG acts to stiffen the membranes of cancer cells, leading to inhibition of signaling pathways of various receptors. Stiffening of membranes with EGCG inhibited AXL receptor tyrosine kinase, a stimulator of cell softening, motility and stemness, and expression of programmed cell death-ligand 1. This review covers the following: i) primary cancer prevention using EGCG or green tea, ii) tertiary cancer prevention by combining EGCG and anticancer drugs, iii) inhibition of metastasis with EGCG by stiffening the cell membrane, iv) inhibition of AXL receptor tyrosine kinase, a stimulator of cell softening and motility, with EGCG, v) inhibition of stemness properties with EGCG, and vi) EGCG as an alternative chemical immune checkpoint inhibitor. Development of new drugs that enhance stiffening of cancer cell membranes may be an effective strategy for tertiary cancer prevention and treatment.

AFM Force Relaxation Curve Reveals That the Decrease of Membrane Tension Is the Essential Reason for the Softening of Cancer Cells

Differences in stiffness constitute an extremely important aspect of the mechanical differences between cancer cells and normal cells, and atomic force microscopy (AFM) is the most commonly used tool to characterize the difference in stiffness. However, the process of mechanical characterization using AFM has been controversial and the influence of the membrane tension on AFM measurement results was often ignored. Here, a physical model involving a simultaneous consideration of the effects of the cell membrane, cytoskeleton network and cytosol was proposed. We carried out a theoretical analysis of AFM force relaxation curves, and as a result solved many of the remaining controversial issues regarding AFM-based mechanical characterization of cells, and provided a quantitative solution for the membrane tension measured using AFM indentation experiments for the first time. From the results of experiments on cells with different adherent shapes and different pairs of normal cells and cancer cells, we found additional force provided by membrane tension to be the main component of the force applied to the AFM probe, with decreased cell membrane tension being the essential reason for the greater softness of cancer cells than of normal cells. Hence, regulating membrane tension may become an important method for regulating the behavior of cancer cells.

Salinomycin inhibits proliferative vitreoretinopathy formation in a mouse model

Proliferative vitreoretinopathy (PVR) is a progressive disease that develops in a subset of patients who undergo surgery for retinal detachment repair, and results in significant vision loss. PVR is characterized by the migration of retinal pigment epithelial (RPE) cells into the vitreous cavity, where they undergo epithelial-to-mesenchymal transition and form contractile membranes within the vitreous and along the retina, resulting in recurrent retinal detachments. Currently, surgical intervention is the only treatment for PVR and there are no pharmacological agents that effectively inhibit or prevent PVR formation. Here, we show that a single intravitreal injection of the polyether ionophore salinomycin (SNC) effectively inhibits the formation of PVR in a mouse model with no evidence of retinal toxicity. After 4 weeks, fundus photography and optical coherence tomography (OCT) demonstrated development of mean PVR grade of 3.5 (SD: 1.3) in mouse eyes injected with RPE cells/DMSO (vehicle), compared to mean PVR grade of 1.6 (SD: 1.3) in eyes injected with RPE cells/SNC (p = 0.001). Additionally, immunohistochemistry analysis showed RPE cells/SNC treatment reduced both fibrotic (αSMA, FN1, Vim) and inflammatory (GFAP, CD3, CD20) markers compared to control RPE cells/DMSO treatment. Finally, qPCR analysis confirmed that Tgfβ, Tnfα, Mcp1 (inflammatory/cytokine markers), and Fn1, Col1a1 and Acta2 (fibrotic markers) were significantly attenuated in the RPE cells/SNC group compared to RPE/DMSO control. These results suggest that SNC is a potential pharmacologic agent for the prevention of PVR in humans and warrants further investigation.

Amikacin Suppresses Human Breast Cancer Cell MDA-MB-231 Migration and Invasion

(1) Background: Amikacin is an aminoglycoside antibiotic used for treating gram-negative bacterial infections in cancer patients. In this study, our aims are to investigate the migratory inhibition effects of amikacin in human MDA-MB-231 cells. (2) Methods: We used a wound-healing assay, trans-well analysis, Western blotting, immunostaining and siRNA knockdown approaches to investigate how amikacin influenced MDA-MB-231 cell migration and invasion. (3) Results: Wound healing showed that the MDA-MB-231 cell migration rates decreased to 44.4% in the presence of amikacin. Trans-well analysis showed that amikacin treatment led to invasion inhibition. Western blotting demonstrated that amikacin induced thioredoxin-interacting protein (TXNIP) up-regulation. TXNIP was knocked down using siRNA in MDA-MB-231 cell. Using immunostaining analysis, we found that inhibition of TXNIP expression led to MDA-MB-231 pseudopodia extension; however, amikacin treatment attenuated the cell extension formation. (4) Conclusions: We observed inhibition of migration and invasion in MDA-MB-231 cells treated with amikacin. This suggests inhibition might be mediated by up-regulation of TXNIP.

Recent advances in AFM-based biological characterization and applications at multiple levels

Atomic force microscopy (AFM) has found a wide range of bio-applications in the past few decades due to its ability to measure biological samples in natural environments at a high spatial resolution. AFM has become a key platform in biomedical, bioengineering and drug research fields, enabling mechanical and morphological characterization of live biological systems. Hence, we provide a comprehensive review on recent advances in the use of AFM for characterizing the biomechanical properties of multi-scale biological samples, ranging from molecule, cell to tissue levels. First, we present the fundamental principles of AFM and two AFM-based models for the characterization of biomechanical properties of biological samples, covering key AFM devices and AFM bioimaging as well as theoretical models for characterizing the elasticity and viscosity of biomaterials. Then, we elaborate on a series of new experimental findings through analysis of biomechanics. Finally, we discuss the future directions and challenges. It is envisioned that the AFM technique will enable many remarkable discoveries, and will have far-reaching impacts on bio-related studies and applications in the future.

Cryptotanshinone attenuates the stemness of non-small cell lung cancer cells via promoting TAZ translocation from nuclear to cytoplasm

Background

Cancer stem cells (CSCs) are regarded as the root of tumor progression, thus representing an anti-cancer therapy through targeting this cell sub-population.

Methods

Non-small cell lung cancer (NSCLC) CSCs were enriched by non-adherent spheroid formation analysis. Lentivirus infection was used to stably change gene expression. Cell cycle, EdU incorporation, cell apoptosis, cell viability, ALDH1 activity, spheroid formation and in vivo tumor initiation assays were performed to detect the effects of Cryptotanshinone (CT), a traditional Chinese herb medicine, on the stemness of NSCLC cells. RNA-sequencing combined qRT-PCR and western blot analysis were constructed to explore the underlying mechanism contributing to CT-mediated effects.

Results

CT could attenuate the stemness of NSCLC CSCs, as evident by the reduced spheroid formation ability, stemness marker expression and ALDH1 activity. Additionally, CT provoked NSCLC CSCs entry into the cell cycle. RNA-sequencing analysis showed that Hippo signaling pathway was highly enriched in NSCLC CSCs with CT treatment. Further experiments disclosed that CT decreased TAZ (a regulatory master of Hippo pathway) expression via promoting its nuclear-cytoplasm translocation in NSCLC CSCs. Also, overexpression of TAZ partially saved the attenuation of CT on the stemness of NSCLC CSCs. Notably, CT enhanced the sensitivity of tyrosine kinase inhibitor (TKI) and chemotherapy in NSCLC CSCs.

Conclusions

This work reveals that CT attenuates NSCLC CSC stemness, implying the possibility of CT as an adjuvant therapy for NSCLC.

Cancer Stem Cells: A Potential Breakthrough in HCC-Targeted Therapy

Cancer stem cells (CSCs) are subpopulations of cells with stem cell characteristics that produce both cancerous and non-tumorigenic cells in tumor tissues. The literature reports that CSCs are closely related to the development of hepatocellular carcinoma (HCC) and promote the malignant features of HCC such as high invasion, drug resistance, easy recurrence, easy metastasis, and poor prognosis. This review discusses the origin, molecular, and biological features, functions, and applications of CSCs in HCC in recent years; the goal is to clarify the importance of CSCs in treatment and explore their potential value in HCC-targeted therapy.

Primary Human Hepatocytes, but Not HepG2 or Balb/c 3T3 Cells, Efficiently Metabolize Salinomycin and Are Resistant to Its Cytotoxicity

Salinomycin is a polyether antibiotic showing anticancer activity. There are many reports of its toxicity to animals but little is known about the potential adverse effects in humans. The action of the drug may be connected to its metabolism. That is why we investigated the cytotoxicity of salinomycin and pathways of its biotransformation using human primary hepatocytes, human hepatoma cells (HepG2), and the mouse fibroblast cell line (Balb/c 3T3). The cytotoxicity of salinomycin was time-dependent, concentration-dependent, and cell-dependent with primary hepatocytes being the most resistant. Among the studied models, primary hepatocytes were the only ones to efficiently metabolize salinomycin but even they were saturated at higher concentrations. The main route of biotransformation was monooxygenation leading to the formation of monohydroxysalinomycin, dihydroxysalinomycin, and trihydroxysalinomycin. Tiamulin, which is a known inhibitor of CYP450 izoenzymes, synergistically induced cytotoxicity of salinomycin in all cell types, including non-metabolising fibroblasts. Therefore, the pharmacokinetic interaction cannot fully explain tiamulin impact on salinomycin toxicity.

Roles of the actin cytoskeleton in aging and age-associated diseases

The integrity of the cytoskeleton is essential to diverse cellular processes such as phagocytosis and intracellular trafficking. Disruption of the organization and dynamics of the actin cytoskeleton leads to age-associated symptoms and diseases, ranging from cancer to neurodegeneration. In addition, changes in the integrity of the actin cytoskeleton disrupt the functioning of not only somatic and stem cells but also gametes, resulting in aberrant embryonic development. Strategies to preserve the integrity and dynamics of the cytoskeleton are, therefore, potentially therapeutic to age-related disorders. The objective of this article is to revisit the current understanding of the roles played by the actin cytoskeleton in aging, and to review the opportunities and challenges for the transition of basic research into intervention development. It is hoped that, with the snapshot of evidence regarding changes in actin dynamics with advanced age, insights into future research directions can be attained.

(-)-Epigallocatechin gallate inhibits stemness and tumourigenicity stimulated by AXL receptor tyrosine kinase in human lung cancer cells

Cancer stem cells (H1299-sdCSCs) were obtained from tumour spheres of H1299 human lung cancer cells. We studied low stiffness, a unique biophysical property of cancer cells, in H1299-sdCSCs and parental H1299. Atomic force microscopy revealed an average Young’s modulus value of 1.52 kPa for H1299-sdCSCs, which showed low stiffness compared with that of H1299 cells, with a Young’s modulus value of 2.24 kPa. (−)-Epigallocatechin gallate (EGCG) reversed the average Young’s modulus value of H1299-sdCSCs to that of H1299 cells. EGCG treatment inhibited tumour sphere formation and ALDH1A1 and SNAI2 (Slug) expression. AXL receptor tyrosine kinase is highly expressed in H1299-sdCSCs and AXL knockdown with siAXLs significantly reduced tumour sphere formation and ALDH1A1 and SNAI2 (Slug) expression. An AXL-high population of H1299-sdCSCs was similarly reduced by treatment with EGCG and siAXLs. Transplantation of an AXL-high clone isolated from H1299 cells into SCID/Beige mice induced faster development of bigger tumour than bulk H1299 cells, whereas transplantation of the AXL-low clone yielded no tumours. Oral administration of EGCG and green tea extract (GTE) inhibited tumour growth in mice and reduced p-AXL, ALDH1A1, and SLUG in tumours. Thus, EGCG inhibits the stemness and tumourigenicity of human lung cancer cells by inhibiting AXL.

Role of Focal Adhesion Kinase in Small-Cell Lung Cancer and Its Potential as a Therapeutic Target

Small-cell lung cancer (SCLC) represents 15% of all lung cancers and it is clinically the most aggressive type, being characterized by a tendency for early metastasis, with two-thirds of the patients diagnosed with an extensive stage (ES) disease and a five-year overall survival (OS) as low as 5%. There are still no effective targeted therapies in SCLC despite improved understanding of the molecular steps leading to SCLC development and progression these last years. After four decades, the only modest improvement in OS of patients suffering from ES-SCLC has recently been shown in a trial combining atezolizumab, an anti-PD-L1 immune checkpoint inhibitor, with carboplatin and etoposide, chemotherapy agents. This highlights the need to pursue research efforts in this field. Focal adhesion kinase (FAK) is a non-receptor protein tyrosine kinase that is overexpressed and activated in several cancers, including SCLC, and contributing to cancer progression and metastasis through its important role in cell proliferation, survival, adhesion, spreading, migration, and invasion. FAK also plays a role in tumor immune evasion, epithelial-mesenchymal transition, DNA damage repair, radioresistance, and regulation of cancer stem cells. FAK is of particular interest in SCLC, being known for its aggressiveness. The inhibition of FAK in SCLC cell lines demonstrated significative decrease in cell proliferation, invasion, and migration, and induced cell cycle arrest and apoptosis. In this review, we will focus on the role of FAK in cancer cells and their microenvironment, and its potential as a therapeutic target in SCLC.

The roles of nuclear focal adhesion kinase (FAK) on Cancer: a focused review

FAK is a tyrosine kinase overexpressed in cancer cells and plays an important role in the progression of tumors to a malignant phenotype. Except for its typical role as a cytoplasmic kinase downstream of integrin and growth factor receptor signaling, related studies have shown new aspects of the roles of FAK in the nucleus. FAK can promote p53 degradation through ubiquitination, leading to cancer cell growth and proliferation. FAK can also regulate GATA4 and IL-33 expression, resulting in reduced inflammatory responses and immune escape. These findings establish a new model of FAK from the cytoplasm to the nucleus. Activated FAK binds to transcription factors and regulates gene expression. Inactive FAK synergizes with different E3 ligases to promote the turnover of transcription factors by enhancing ubiquitination. In the tumor microenvironment, nuclear FAK can regulate the formation of new blood vessels, affecting the tumor blood supply. This article reviews the roles of nuclear FAK in regulating gene expression. In addition, the use of FAK inhibitors to target nuclear FAK functions will also be emphasized.

Salinomycin and its derivatives - A new class of multiple-targeted "magic bullets"

The history of drug development clearly shows the scale of painstaking effort leading to a finished product - a highly biologically active agent that would be at the same time no or little toxic to human organism. Moreover, the aim of modern drug discovery can move from "one-molecule one-target" concept to more promising "one-molecule multiple-targets" one, particularly in the context of effective fight against cancer and other complex diseases. Gratifyingly, natural compounds are excellent source of potential drug leads. One of such promising naturally-occurring drug candidates is a polyether ionophore - salinomycin (SAL). This compound should be identified as multi-target agent for two reasons. Firstly, SAL combines a broad spectrum of bioactivity, including antibacterial, antifungal, antiviral, antiparasitic and anticancer activity, with high selectivity of action, proving its significant therapeutic potential. Secondly, the multimodal mechanism of action of SAL has been shown to be related to its interactions with multiple molecular targets and signalling pathways that are synergistic for achieving a therapeutic anticancer effect. On the other hand, according to the Paul Ehrlich's "magic bullet" concept, invariably inspiring the scientists working on design of novel target-selective molecules, a very interesting direction of research is rational chemical modification of SAL. Importantly, many of SAL derivatives have been found to be more promising as chemotherapeutics than the native structure. This concise review article is focused both on the possible role of SAL and its selected analogues in future antimicrobial and/or cancer therapy, and on the potential use of SAL as a new class of multiple-targeted "magic bullet" because of its multimodal mechanism of action.

Targeting liver cancer stem cells for the treatment of hepatocellular carcinoma

Liver cancer is one of the most common malignant tumors and prognosis remains poor. It has been increasingly recognized that liver cancer stem cells (LCSCs) are responsible for the carcinogenesis, recurrence, metastasis and chemoresistance of hepatocellular carcinoma (HCC). Targeting LCSCs is promising to be a new direction for the treatment of HCC. Herein, we summarize the potentially therapeutic targets in LCSCs at the level of genes, molecules and cells, such as knockout of oncogenes or oncoproteins, restoring the silent tumor suppressor genes, inhibition of the transcription factors and regulation of noncoding RNAs (including microRNAs and long noncoding RNAs) in LCSCs at the genetic level; inhibition of markers and blockade of the key signaling pathways of LCSCs at the molecular level; and inhibiting autophagy and application of oncolytic adenoviruses in LCSCs at the cellular level. Moreover, we analyze the potential targets in LCSCs to eliminate chemoresistance of HCC. Thereinto, the suppression of autophagy and Nanog by chloroquine and shRNA respectively may be the most promising targeting approaches. These targets may provide novel therapeutic strategies for the treatment of HCC by targeting LCSCs.

Enhanced anticancer effect of oncostatin M combined with salinomycin in CD133+ HepG2 liver cancer cells

Oncostatin M (OSM) induces the differentiation of liver cancer stem cells (LCSCs) and increases sensitivity to the chemotherapeutic agent 5-fluorouracil, whereas salinomycin (Sal) induces apoptosis in cancer stem cells and inhibits the proliferation of liver cancer cells. However, there have been no studies investigating the anticancer effects of combination treatment with OSM and Sal. In the present study, we investigated the synergistic effects of OSM and Sal on LCSCs, the CD133⁺ subpopulations from HepG2 human liver cancer cells. CD133⁺ LCSCs were isolated using an immunomagnetic bead technique and identified through colony formation. After incubating with OSM and Sal, the ability of LCSC proliferation and invasion, as well as apoptosis rates were evaluated, and the expression of stemness-related genes was examined by quantitative real-time polymerase chain reaction. Additionally, the secretion of α-fetoprotein (AFP) and albumin (ALB) were analyzed by enzyme-linked immunosorbent assay. Our results indicated that OSM combined with Sal significantly suppressed LCSC proliferation and invasion and induced apoptosis, as determined by flow cytometry and increases in cleaved caspase-3 levels detected by western blotting. The results of the JC-1 staining assay indicated that this effect involved the mitochondrial pathway. Moreover, combination treatment reduced the expression of CD133 in LCSCs and suppressed stemness-related gene expression. Furthermore, the LCSCs produced lower levels of AFP and higher levels of ALB following combination treatment. In all experiments, combination treatment elicited more efficient anticancer effects on LCSCs as compared with single-drug treatment; therefore, our results demonstrated that combined treatment with OSM and Sal inhibited proliferation and induced differentiation and apoptosis in LCSCs, suggesting combined use of OSM and Sal as a therapeutic strategy for liver cancer.

Tendon-Derived Stem Cell Differentiation in the Degenerative Tendon Microenvironment

Tendinopathy is prevalent in athletic and many occupational populations; nevertheless, the pathogenesis of tendinopathy remains unclear. Tendon-derived stem cells (TDSCs) were regarded as the key culprit for the development of tendinopathy. However, it is uncertain how TDSCs differentiate into adipocytes, chondrocytes, or osteocytes in the degenerative microenvironment of tendinopathy. So in this study, the regulating effects of the degenerative tendon microenvironment on differentiation of TDSCs were investigated. TDSCs were isolated from rat Achilles tendons and were grown on normal and degenerative (prepared by stress-deprived culture) decellularized tendon slices (DTSs). Immunofluorescence staining, H&E staining, real-time PCR, and Western blot were used to delineate the morphology, proliferation, and differentiation of TDSCs in the degenerative microenvironment. It was found that TDSCs were much more spread on the degenerative DTSs than those on normal DTSs. The tenocyte-related markers, COL1 and TNMD, were highly expressed on normal DTSs than the degenerative DTSs. The expression of chondrogenic and osteogenic markers, COL2, SOX9, Runx2, and ALP, was higher on the degenerative DTSs compared with TDSCs on normal DTSs. Furthermore, phosphorylated FAK and ERK1/2 were reduced on degenerative DTSs. In conclusion, this study found that the degenerative tendon microenvironment induced TDSCs to differentiate into chondrogenic and osteogenic lineages. It could be attributed to the cell morphology changes and reduced FAK and ERK1/2 activation in the degenerative microenvironment of tendinopathy.

MicroRNA-150 suppresses the growth and malignant behavior of papillary thyroid carcinoma cells via downregulation of MUC4

Previous studies have revealed that microRNA (miR)-150 can act as an oncomiR or a tumor suppressor in numerous types of hematological malignancy and solid tumor. However, the function of miR-150 in papillary thyroid carcinoma (PTC) remains elusive. The present study aimed to investigate the function of miR-150 in PTC and its underlying molecular mechanism. The expression of miR-150 was identified to be significantly downregulated, whereas that of mucin (MUC)4 was significantly upregulated in PTC tissues and cell lines compared with corresponding controls. Further experiments demonstrated that MUC4 is a direct target of miR-150. PTC cell proliferation and capacity for migration and invasion decreased following miR-150 overexpression. It was also demonstrated that miR-150-mediated MUC4 downregulation was associated with an accompanying decrease in human epidermal growth factor receptor 2, as well as its phosphorylated form, resulting in suppressed activation of downstream signaling. In conclusion, the present study demonstrated that miR-150 may serve a key function in suppressing the malignant growth and aggressive behavior of PTC cells through the downregulation of MUC4. These findings may provide a novel approach for diagnostic and therapeutic strategies for PTC.

Low-level shear stress promotes migration of liver cancer stem cells via the FAK-ERK1/2 signalling pathway

Cancer stem cells (CSCs) are a small subpopulation of tumour cells that have been proposed to be responsible for cancer initiation, chemotherapy resistance and cancer recurrence. Shear stress activated cellular signalling is involved in cellular migration, proliferation and differentiation. However, little is known about the effects of shear stress on the migration of liver cancer stem cells (LCSCs). Here, we studied the effects of shear stress that are generated from a parallel plated flow chamber system, on LCSC migration and the activation of focal adhesion kinase (FAK) and extracellular signal regulated kinase1/2 (ERK1/2), using transwell assay and western blot, respectively. We found that 2 dyne/cm² shear stress loading for 6 h promotes LCSC migration and activation of the FAK and ERK1/2 signalling pathways, whereas treatment with the FAK phosphorylation inhibitor PF573228 or the ERK1/2 phosphorylation inhibitor PD98059 suppressed the shear stress-promoted migration, indicating the involvement of FAK and ERK1/2 activation in shear stress-induced LCSC migration. Additionally, atomic force microscopy (AFM) analysis showed that shear stress lowers LCSC stiffness via the FAK and ERK1/2 pathways, suggesting that the mechanism by which shear stress promotes LCSC migration might partially be responsible for the decrease in cell stiffness. Further experiments focused on the role of the actin cytoskeleton, demonstrating that the F-actin filaments in LCSCs are less well-defined after shear stress treatment, providing an explanation for the reduction in cell stiffness and the promotion of cell migration. Overall, our study demonstrates that shear stress promotes LCSC migration through the activation of the FAK-ERK1/2 signalling pathways, which further results in a reduction of organized actin and softer cell bodies.

Au-Se-Bond-Based Nanoprobe for Imaging MMP-2 in Tumor Cells under a High-Thiol Environment

The gold nanosensors based on the Au-S bond have been widely applied to biochemical detections. However, signal distortion caused by biothiols has been seldom mentioned and urgently needs to be solved. Herein, we designed a novel but easily assembled gold nanoprobe by coupling a selenol-modified peptide with FITC onto the gold nanoparticle's surface via an Au-Se bond for fluorescence imaging of a tumor marker matrix, metalloproteinases 2 (MMP-2). Compared to the Au-S probes, the Au-Se probes display high thermal stability and a very good anti-interference ability toward glutathione under simulated physiological conditions. More importantly, the Au-Se nanoprobe exhibits a high-fidelity fluorescent signal toward MMP-2, effectively avoiding interference caused by high levels of thiol compounds in vivo. In addition, in vivo experiments further proved that no significant signal intensity change for the tumor cells treated by the Au-Se probes was observed before and after eliminating glutathione. Hence, we believe such Au-Se probes with in vivo glutathione interfering resistance offer new routes and perspectives in biology and medicine in the future.

Dioscin Inhibits HSC-T6 Cell Migration via Adjusting SDC-4 Expression: Insights from iTRAQ-Based Quantitative Proteomics

Hepatic stellate cells (HSCs) migration, an important bioprocess, contributes to the development of liver fibrosis. Our previous studies have found the potent activity of dioscin against liver fibrosis by inhibiting HSCs proliferation, triggering the senescence and inducing apoptosis of activated HSCs, but the molecular mechanisms associated with cell migration were not clarified. In this work, iTRAQ (isobaric tags for relative and absolution quantitation)-based quantitative proteomics study was carried out, and a total of 1566 differentially expressed proteins with fold change ≥2.0 and p < 0.05 were identified in HSC-T6 cells treated by dioscin (5.0 μg/mL). Based on Gene Ontology classification, String and KEGG pathway assays, the effects of dioscin to inhibit cell migration via regulating SDC-4 were carried out. The results of wound-healing, cell migration and western blotting assays indicated that dioscin significantly inhibit HSC-T6 cell migration through SDC-4-dependent signal pathway by affecting the expression levels of Fn, PKCα, Src, FAK, and ERK1/2. Specific SDC-4 knockdown by shRNA also blocked HSC-T6 cell migration, and dioscin slightly enhanced the inhibiting effect. Taken together, the present work showed that SDC-4 played a crucial role on HSC-T6 cell adhesion and migration of dioscin against liver fibrosis, which may be one potent therapeutic target for fibrotic diseases.

Salinomycin's potential to eliminate glioblastoma stem cells and treat glioblastoma multiforme (Review)

Glioblastoma multiforme (GBM) is the most common and deadliest form of primary brain tumor. Despite treatment with surgery, radiotherapy, and chemotherapy with the drug temozolomide, the expected survival after diagnosis remains low. The median survival is only 14.6 months and the two-year survival is a mere 30%. One reason for this is the heterogeneity of GBM including the presence of glioblastoma cancer stem cells (GSCs). GSCs are a subset of cells with the unique ability to proliferate, differentiate, and create tumors. GSCs are resistant to chemotherapy and radiation and thought to play an important role in recurrence. In order to effectively treat GBM, a drug must be identified that can kill GSCs. The ionophore salinomycin has been shown to kill cancer stem cells and is therefore a promising future treatment for GBM. This study focuses on salinomycin's potential to treat GBM including its ability to reduce the CSC population, its toxicity to normal brain cells, its mechanism of action, and its potential for combination treatment.

Tg737 acts as a key driver of invasion and migration in liver cancer stem cells and correlates with poor prognosis in patients with hepatocellular carcinoma

We previously demonstrated that the Tg737 gene plays a critical role in the carcinogenesis of hepatocellular carcinoma (HCC). However, few systematic investigations have focused on the biological function of Tg737 in the invasion and migration of liver cancer stem cells (LCSCs) and on its clinical significance. In this study, Tg737 overexpression was achieved via gene transfection in MHCC97-H side population (SP) cells, which are considered a model for LCSCs in scientific studies. Tg737 overexpression significantly inhibited the invasion and migration of SP cells in an extracellular signal-regulated kinase1/2 (ERK1/2)/matrix metalloproteinase-2 (MMP-2)-dependent manner. Furthermore, Tg737 expression was frequently decreased in HCC tissues relative to that in adjacent noncancerous liver tissues. This decreased expression was significantly associated with tumor differentiation, the American Joint Committee on Cancer (AJCC) stage, metastasis, tumor size, vascular invasion, alpha-fetoprotein (AFP) levels, and tumor number. Moreover, multivariate Cox regression analyses demonstrated that Tg737 expression was an independent factor for predicting the overall survival of HCC patients. Notably, Kaplan-Meier analysis further showed that overall survival was significantly worse among patients with low Tg737 expression. Collectively, our findings demonstrated that Tg737 is a poor prognostic marker in patients with HCC, which may be due to its ability to promote LCSCs invasion and migration. These results provide a basis for investigating of Tg737 as a novel prognostic biomarker and therapeutic target.