A partial epithelial-mesenchymal transition signature for highly aggressive colorectal cancer cells that survive under nutrient restriction.

Partial epithelial-mesenchymal transition (p-EMT) has recently been identified as a hybrid state consisting of cells with both epithelial and mesenchymal characteristics and is associated with the migration, metastasis, and chemoresistance of cancer cells. Here, we describe the induction of p-EMT in starved colorectal cancer (CRC) cells and identify a p-EMT gene signature that can predict prognosis. Functional characterisation of starvation-induced p-EMT in HCT116, DLD1, and HT29 cells showed changes in proliferation, morphology, and drug sensitivity, supported by in vivo studies using the chorioallantoic membrane model. An EMT-specific quantitative polymerase chain reaction (qPCR) array was used to screen for deregulated genes, leading to the establishment of an in silico gene signature that was correlated with poor disease-free survival in CRC patients along with the CRC consensus molecular subtype CMS4. Among the significantly deregulated p-EMT genes, a triple-gene signature consisting of SERPINE1, SOX10, and epidermal growth factor receptor (EGFR) was identified. Starvation-induced p-EMT was characterised by increased migratory potential and chemoresistance, as well as E-cadherin processing and internalisation. Both gene signature and E-cadherin alterations could be reversed by the proteasomal inhibitor MG132. Spatially resolving EGFR expression with high-resolution immunofluorescence imaging identified a proliferation stop in starved CRC cells caused by EGFR internalisation. In conclusion, we have gained insight into a previously undiscovered EMT mechanism that may become relevant when tumour cells are under nutrient stress, as seen in early stages of metastasis. Targeting this process of tumour cell dissemination might help to prevent EMT and overcome drug resistance. © 2024 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

ATF2 loss promotes tumor invasion in colorectal cancer cells via upregulation of cancer driver TROP2.

In cancer, the activating transcription factor 2 (ATF2) has pleiotropic functions in cellular responses to growth stimuli, damage, or inflammation. Due to only limited studies, the significance of ATF2 in colorectal cancer (CRC) is not well understood. We report that low ATF2 levels correlated with worse prognosis and tumor aggressiveness in CRC patients. NanoString gene expression and ChIP analysis confirmed trophoblast cell surface antigen 2 (TROP2) as a novel inhibitory ATF2 target gene. This inverse correlation was further observed in primary human tumor tissues. Immunostainings revealed that high intratumoral heterogeneity for ATF2 and TROP2 expression was sustained also in liver metastasis. Mechanistically, our in vitro data of CRISPR/Cas9-generated ATF2 knockout (KO) clones revealed that high TROP2 levels were critical for cell de-adhesion and increased cell migration without triggering EMT. TROP2 was enriched in filopodia and displaced Paxillin from adherens junctions. In vivo imaging, micro-computer tomography, and immunostainings verified that an ATF2KO/TROP2high status triggered tumor invasiveness in in vivo mouse and chicken xenograft models. In silico analysis provided direct support that ATF2low/TROP2high expression status defined high-risk CRC patients. Finally, our data demonstrate that ATF2 acts as a tumor suppressor by inhibiting the cancer driver TROP2. Therapeutic TROP2 targeting might prevent particularly the first steps in metastasis, i.e., the de-adhesion and invasion of colon cancer cells.

Development of ACE2 loaded decoy liposomes and their effect on SARS-CoV-2 for Covid-19 treatment.

SARS-CoV-2 is a novel coronavirus with a positively oriented single-stranded RNA that first appeared in December 2019. In this study, Angiotensin Converting Enzyme 2 (ACE2) loaded decoy liposomes were developed and characterized. ACE2 protein was loaded onto a liposomal carrier system and its toxicity and effectiveness were evaluated in cell culture and in vitro virus neutralization studies. Liposomes were prepared with the film hydration method and adjusted for size with the dialysis membrane method or the ultrasonic homogenization method. All formulations showed high entrapment efficiency between 99.98-79.6%. Liposomes with two different particle sizes above 2 µm and below 500 nm were obtained with the dialysis membrane method and homogenization method. Two optimum formulations, M6-S90 with a PDI value of 0.383 ± 0.053 and particle size of 397.7 ± 28.25 nm which was produced by ultrasonic homogenization and M6-4 with a PDI 0.769 ± 0.205 and particle size of 2606 ± 1396.00 were chosen as optimum formulations for further studies. M6-S90 was stable and showed low toxicity on Calu3 lung epithelial cells. Pre-incubation of M6-S90 with with 3.1 × 105 PFU/mL of SARS-CoV-2 followed by incubation with Vero E6 cells resulted in a 4 log fold change reduction in cell death compared to virus alone. This suggests that MS6-S90 had good neutralization activity on SARS-CoV-2 whilst maintaining viability of the host cell. The novel ACE-2 loaded decoy liposomes described in this study can be further evaluated for the treatment of COVID-19.

Aldo Keto Reductases AKR1B1 and AKR1B10 in Cancer: Molecular Mechanisms and Signaling Networks.

Deregulation of metabolic pathways has increasingly been appreciated as a major driver of cancer in recent years. The principal cancer-associated alterations in metabolism include abnormal uptake of glucose and amino acids and the preferential use of metabolic pathways for the production of biomass and nicotinamide adenine dinucleotide phosphate (NADPH). Aldo-keto reductases (AKRs) are NADPH dependent cytosolic enzymes that can catalyze the reduction of carbonyl groups to primary and secondary alcohols using electrons from NADPH. Aldose reductase, also known as AKR1B1, catalyzes the conversion of excess glucose to sorbitol and has been studied extensively for its role in a number of diabetic pathologies. In recent years, however, high expression of the AKR1B and AKR1C family of enzymes has been strongly associated with worse outcomes in different cancer types. This review provides an overview of the catalysis-dependent and independent data emerging on the molecular mechanisms of the functions of AKRBs in different tumor models with an emphasis of the role of these enzymes in chemoresistance, inflammation, oxidative stress and epithelial-to-mesenchymal transition.

Evaluation of an aldo-keto reductase gene signature with prognostic significance in colon cancer via activation of epithelial to mesenchymal transition and the p70S6K pathway.

AKR1B1 and AKR1B10, members of the aldo-keto reductase family of enzymes that participate in the polyol pathway of aldehyde metabolism, are aberrantly expressed in colon cancer. We previously showed that high expression of AKR1B1 (AKR1B1HIGH) was associated with enhanced motility, inflammation and poor clinical outcome in colon cancer patients. Using publicly available datasets and ex vivo gene expression analysis (n = 51, Ankara cohort), we have validated our previous in silico finding that AKR1B1HIGH was associated with worse overall survival (OS) compared with patients with low expression of AKR1B1 (AKR1B1LOW) samples. A combined signature of AKR1B1HIGH and AKR1B10LOW was significantly associated with worse recurrence-free survival (RFS) in microsatellite stable (MSS) patients and in patients with distal colon tumors as well as a higher mesenchymal signature when compared with AKR1B1LOW/AKR1B10HIGH tumors. When the patients were stratified according to consensus molecular subtypes (CMS), AKR1B1HIGH/AKR1B10LOW samples were primarily classified as CMS4 with predominantly mesenchymal characteristics while AKR1B1LOW/AKR1B10HIGH samples were primarily classified as CMS3 which is associated with metabolic deregulation. Reverse Phase Protein Array carried out using protein samples from the Ankara cohort indicated that AKR1B1HIGH/AKR1B10LOW tumors showed aberrant activation of metabolic pathways. Western blot analysis of AKR1B1HIGH/AKR1B10LOW colon cancer cell lines also suggested aberrant activation of nutrient-sensing pathways. Collectively, our data suggest that the AKR1B1HIGH/AKR1B10LOW signature may be predictive of poor prognosis, aberrant activation of metabolic pathways, and can be considered as a novel biomarker for colon cancer prognostication.

15-LOX-1 has diverse roles in the resensitization of resistant cancer cell lines to doxorubicin.

Lipoxygenases (LOXs) are a family of enzymes that can oxygenate polyunsaturated fatty acids. As a member of the family, 15-lipoxygenase-1 (15-LOX-1) specifically metabolizes arachidonic acid and linoleic acid. 15-LOX-1 can affect physiological and pathophysiological events via regulation of the protein-lipid interactome, alterations in intracellular redox state and production of lipid metabolites that are involved in the induction and resolution of inflammation. Although several studies have shown that 15-LOX-1 has an antitumorigenic role in many different cancer models, including breast cancer, the role of the protein in cancer drug resistance has not been established yet. In this study, we, for the first time, aimed to show the potential role of 15-LOX-1 in acquired doxorubicin (DOX) resistance in MCF7 and HeLa cancer cell lines. Our results show that ALOX15 was transcriptionally downregulated in DOX-resistant cells compared with their drug-sensitive counterparts. Moreover, overexpression of ALOX15 in the drug-resistant cells resulted in resensitization of those cells to DOX in a cell-dependent manner. 15-LOX-1 expression could induce apoptosis by activating PPARγ and enhance the accumulation of DOX in drug-resistant MCF7 cells by altering cellular motility properties, and membrane dynamics. However, HeLa DOX cells did not show any of these effects but were susceptible to cell death when treated with 13(S)-HODE. These results underline the role and importance of 15-LOX-1 in cancer drug resistance, and points to novel mechanisms as a therapeutic approach to overcome cancer drug resistance.

Tumor-derived exosomes in the regulation of macrophage polarization.

BACKGROUND: This review focuses on exosomes derived from various cancer cells. The review discusses the possibility of differentiating macrophages in alternatively activated anti-inflammatory pro-tumorigenic M2 macrophage phenotypes and classically activated pro-inflammatory, anti-tumorigenic M1 macrophage phenotypes in the tumor microenvironment (TME). The review is divided into two main parts, as follows: (1) role of exosomes in alternatively activating M2-like macrophages-breast cancer-derived exosomes, hepatocellular carcinoma (HCC) cell-derived exosomes, lung cancer-derived exosomes, prostate cancer-derived exosomes, Oral squamous cell carcinoma (OSCC)-derived exosomes, epithelial ovarian cancer (EOC)-derived exosomes, Glioblastoma (GBM) cell-derived exosomes, and colorectal cancer-derived exosomes, (2) role of exosomes in classically activating M1-like macrophages, oral squamous cell carcinoma-derived exosomes, breast cancer-derived exosomes, Pancreatic-cancer derived modified exosomes, and colorectal cancer-derived exosomes, and (3) exosomes and antibody-dependent cellular cytotoxicity (ADCC). This review addresses the following subjects: (1) crosstalk between cancer-derived exosomes and recipient macrophages, (2) the role of cancer-derived exosome payload(s) in modulating macrophage fate of differentiation, and (3) intracellular signaling mechanisms in macrophages regarding the exosome's payload(s) upon its uptake and regulation of the TME. EVIDENCE: Under the electron microscope, nanoscale exosomes appear as specialized membranous vesicles that emerge from the endocytic cellular compartments. Exosomes harbor proteins, growth factors, cytokines, lipids, miRNA, mRNA, and DNAs. Exosomes are released by many cell types, including reticulocytes, dendritic cells, B-lymphocytes, platelets, mast cells, and tumor cells. It is becoming clear that exosomes can impinge upon signal transduction pathways, serve as a mediator of signaling crosstalk, thereby regulating cell-to-cell wireless communications. CONCLUSION: Based on the vesicular cargo, the molecular constituents, the exosomes have the potential to change the fate of macrophage phenotypes, either M1, classically activated macrophages, or M2, alternatively activated macrophages. In this review, we discuss and describe the ability of tumor-derived exosomes in the mechanism of macrophage activation and polarization.

Low-dose curcumin reduced TNBS-associated mucin depleted foci in mice by scavenging superoxide anion and lipid peroxides, rebalancing matrix NO synthase and aconitase activities, and recoupling mitochondria.

BACKGROUND: The role of mitochondrial dysfunction in the pathogenesis of inflammatory bowel diseases (IBD) is still being investigated. This study evaluated the therapeutic effect of curcumin (Cur), a polyphenolic electrophile in 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced chronic colitis and mitochondrial dysfunction, in mice. METHODS: Colitis was induced by rectal instillation to mice of 30 mg kg-1 TNBS, alone or followed by daily intraperitoneal injections of Cur 25 mg kg-1. Animals were euthanized at days 3, 7, and 14, post TNBS challenge. Colon mitochondria of control mice were treated with 5 µM Cur, and TNBS (50, 100 µM)-toxicity was evaluated by measuring swelling, respiration, and aconitase and fumarase activities. Redox status was evaluated in colon mucosa and in mitochondria. RESULTS: In vitro, a short-term Cur treatment controlled the dose and time dependent mitochondrial toxicity induced by TNBS, by collapsing the generation of superoxide anion and hydroperoxy lipids, rebalancing nitric oxide synthase and aconitase activities, and recoupling mitochondria. In vivo, a daily low-dose Cur abolished mice mortality which reached 27% in model group. Cur improved in a time dependent manner mucosal redox homeostasis, cell apoptosis, mucin depleted crypts and crypt abscesses by controlling prooxidant activity of myeloperoxidase and NO synthase associated to phagocytes influx, quenching hydroperoxy lipids, and reboosting GSH levels. CONCLUSION: Cur, by quenching intra and extra mitochondrial ROS generation, rebalancing aconitase/fumarase and MDA/GSH ratios, and recoupling mitochondria, may support mithormesis priming and remitting in IBD.

Drug repositioning as an effective therapy for protease-activated receptor 2 inhibition.

Proteinase-activated receptor 2 (PAR-2) is a G protein-coupled receptor activated by both trypsin and a specific agonist peptide, SLIGKV-NH2. It has been linked to various pathologies, including pain and inflammation. Several peptide and peptidomimetic agonizts for PAR-2 have been developed exhibiting high potency and efficacy. However, the number of PAR-2 antagonists is smaller. We screened the Food and Drug Administration library of approved compounds to retrieve novel antagonists for repositioning in the PAR-2 structure. The most efficacious compound bicalutamide bound to the PAR-2 binding groove near the extracellular domain as observed in the in silico studies. Further, it showed reduced Ca2+ release in trypsin activated cells in a dose-dependent manner. Hence, bicalutamide is a novel and potent PAR-2 antagonist which could be therapeutically useful in blocking multiple pathways diverging from PAR-2 signaling. Further, the novel scaffold of bicalutamide represents a new molecular structure for PAR-2 antagonism and can serve as a basis for further drug development.

NOS1-derived nitric oxide facilitates macrophage uptake of low-density lipoprotein.

Foam cell formation is a hallmark event during atherosclerosis. The current paradigm is that lipid uptake by a scavenger receptor in macrophages initiates necrosis core formation that characterizes atherosclerosis. We report that NOS1-derived nitric oxide (NO) facilitates low-density lipoprotein (LDL) uptake by macrophages independent of the inflammatory response. LDL uptake could be dramatically suppressed by NOS1 specific inhibitor 1-(2-trifluoromethylphenyl) imidazole (TRIM). Importantly, the notion that NOS1 can mediate uptake of lipoproteins suggests that the foam cell formation is regulated by NOS1-derived NO-mediated mechanism. This is a novel study involving NOS1 as a critical player of foam cell formation and reveals much about the key molecular proteins involved in atherosclerosis. Targeting NOS1 would be a useful strategy in reducing LDL uptake by macrophages and hence dampening the atherosclerosis progression.

Biologically Functional Ultrathin Films Made of Zwitterionic Block Copolymer Micelles.

We report the preparation of ultrathin coatings of zwitterionic block copolymer micelles and a comparison of their protein adsorption, adhesiveness, and antibacterial properties. Zwitterionic block copolymer micelles were obtained through pH-induced self-assembly of poly[3-dimethyl(methacryloyloxyethyl)ammonium propanesulfonate- b-2-(diisopropylamino)ethyl methacrylate] (ßPDMA- b-PDPA) at pH 7.5. ßPDMA- b-PDPA micelles with zwitterionic ßPDMA-corona and pH-responsive PDPA-core were then used as building blocks to prepare layer-by-layer (LbL) assembled multilayer films together with hyaluronic acid (HA), tannic acid (TA), or poly(sodium 4-styrenesulfonate) (PSS). Protein adsorption tests showed that 3-layer ßPDMA- b-PDPA micelles/HA films were the most effective to reduce the adhesion of BSA, lysozyme, ferritin, and casein. In contrast, ßPDMA- b-PDPA micelles/TA films were the most attractive surfaces for protein adsorption. Bacterial antiadhesive tests against a model Gram-negative bacterium, Escherichia coli, and a model Gram-positive bacterium, Staphylococcus aureus, were in good agreement with the protein adsorption properties of the films. The differences in the antiadhesive properties between these three different film systems are discussed within the context of chemical nature and the functional chemical groups of the polyanions, layer number, and surface morphology of the films. Multilayers were found to lose their antiadhesiveness in the long term. However, by taking advantage of the pH-responsive hydrophobic micellar cores, we show that an antibacterial agent could be loaded into the micelles and multilayers could exhibit antibacterial activity in the long term especially at moderately acidic conditions. In contrast to antiadhesive properties, no significant differences were recorded in the antibacterial properties between the different film types.

Synthesis, Characterization and Evaluation of Cytotoxic Activities of Novel Aziridinyl Phosphonic Acid Derivatives.

New aziridine 2-phosphonic acids were prepared by monohydrolysis of the aziridine 2-phosphonates that were obtained by the modified Gabriel-Cromwell reaction of vinyl phosphonate or α-tosylvinyl phosphonate with a primary amine or a chiral amine. The cellular cytotoxicity of these compounds was tested against the HCT-116 colorectal cancer cell lines and the CCD-18Co normal colon fibroblast lines using the MTT assay. Three of the synthesized phosphonic acid derivatives 2e (ethyl hydrogen {(2S)-1-[(1S)-1-(naphthalen-2-yl)ethyl]aziridin-2-yl}phosphonate), 2h (ethyl hydrogen (1-benzylaziridin-2-yl)phosphonate), and 2i (ethyl hydrogen (1-cyclohexylaziridin-2-yl)phosphonate) showed higher cytotoxicity than the reference cancer treatment agent etoposide. Cell death was through a robust induction of apoptosis even more effectively than etoposide, a well-known apoptosis inducing agent.

CHNQ, a novel 2-Chloro-1,4-naphthoquinone derivative of quercetin, induces oxidative stress and autophagy both in vitro and in vivo.

Quercetin (Qc) shows strong antitumor effects but has limited clinical application due to poor water solubility and bioavailability. In a screening of novel semi-synthetic derivatives of Qc, 3,7-dihydroxy-2-[4-(2-chloro-1,4-naphthoquinone-3-yloxy)-3-hydroxyphenyl]-5-hydroxychromen-4-one (CHNQ) could ameliorate acetic acid induced acute colitis in vivo more efficiently than Qc. Since inflammation contributes to colorectal cancer (CRC), we have hypothesized that CHNQ may have anti-cancer effects. Using CRC cell lines HCT-116 and HT-29, we report that CHNQ was three-fold more cytotoxic than Qc along with a robust induction of apoptosis. As expected from naphthoquinones such as CHNQ, a strong induction of oxidative stress was observed. This was accompanied by reactive oxygen species (ROS) induced autophagy marked by a dramatic increase in the lipidation of LC3, decreased activation of Akt/PKB, acidic vesicle accumulation and puncta formation in HCT-116 cells treated with CHNQ. Interestingly, an incomplete autophagy was observed in HT-29 cells where CHNQ treatment led to LC3 lipidation, but not the formation of acidic vacuoles. CHNQ-induced cytotoxicity, ROS formation and autophagy were also detected in vivo in Saccharomyces cerevisiae strain RDKY3615 (WinstonS288C background). Overall, we propose that CHNQ can induce cancer cell death through the induction of oxidative stress, and may be examined further as a potential chemotherapeutic drug.

Ethanolic Extract of Bark from Salix aegyptiaca Ameliorates 1,2-dimethylhydrazine-induced Colon Carcinogenesis in Mice by Reducing Oxidative Stress.

We have previously shown that ethanolic extract from bark (EEB) of Salix aegyptiaca (Musk Willow) can inhibit proliferation and motility and induce apoptosis in colon cancer cells. Tandem mass spectrometry revealed EEB to be rich in catechin, catechol, and salicin. The present study investigated the chemopreventive effect of HPLC-fingerprinted EEB on 1,2-dimethylhydrazine (DMH)-induced aberrant crypt foci (ACF) formation in mice. DMH (20 mg/kg body weight) was weekly injected subcutaneously to mice for the first 2 weeks. EEB (100 and 400 mg/kg body weight) was provided orally from the 7th to 14th week, after which colon tissues were evaluated histologically and biochemically. DMH treatment induced high number of ACF; EEB significantly reduced the number and multiplicity of ACF, along with a restoration in goblet cells and mucin accumulation. EEB supplementation improved the markers of inflammation (myeloperoxidase and neutrophil infiltration) and oxidative stress. More importantly, EEB amplified apoptosis of neoplastic cells in the colon mucosa of DMH-treated mice. It also lowered levels of markers for early transformation events such as EGFR, nuclear ß-catenin, and COX-2 in colon cancer cell lines HT-29 and HCT-116. The innocuity of EEB (up to 1600 mg/kg) to mice reinforces its potential as a chemopreventive agent.

2-Chloro-1,4-naphthoquinone derivative of quercetin as an inhibitor of aldose reductase and anti-inflammatory agent.

The ability of flavonoids to affect multiple key pathways of glucose toxicity, as well as to attenuate inflammation has been well documented. In this study, the inhibition of rat lens aldose reductase by 3,7-di-hydroxy-2-[4-(2-chloro-1,4-naphthoquinone-3-yloxy)-3-hydroxy-phenyl]-5-hydroxy-chromen-4-one (compound 1), was studied in greater detail in comparison with the parent quercetin (compound 2). The inhibition activity of 1, characterized by IC50 in low micromolar range, surpassed that of 2. Selectivity in relation to the closely related rat kidney aldehyde reductase was evaluated. At organ level in isolated rat lenses incubated in the presence of high glucose, compound 1 significantly inhibited accumulation of sorbitol in a concentration-dependent manner, which indicated that 1 was readily taken up by the eye lens cells and interfered with cytosolic aldose reductase. In addition, compound 1 provided macroscopic protection of colonic mucosa in experimental colitis in rats. At pharmacologically active concentrations, compound 1 and one of its potential metabolite 2-chloro-3-hydroxy-[1,4]-naphthoquinone (compound 3) did not affect osmotic fragility of red blood cells.

The ethanolic extract of bark from Salix aegyptiaca L. inhibits the metastatic potential and epithelial to mesenchymal transition of colon cancer cell lines.

Willow bark extracts have been used for centuries as a natural pain killer. Recently their potential as anticancer agents has been reported. We have shown the high antioxidant activity, phenolic and flavonoid content in the ethanolic extract of bark (EEB) from Salix aegyptiaca, a species endogenous to the Middle East. We have also reported that incubation with EEB resulted in a reduction in cell proliferation through the induction of apoptosis and cell cycle arrest via the inhibition of phosphatidyl inositol 3-kinase/Protein kinase B and mitogen activated protein kinases signaling pathways as strongly as commercial inhibitors. The current study demonstrates the robust inhibition of anchorage-independent growth, motility, migration, and adhesion of colon cancer cell lines HCT-116 and HT-29 by EEB. These in vitro functional changes were accompanied by a restoration of E-cadherin expression, a reduction in EGFR, SNAI1, SNAI2, and Twist1 and the matrix metalloproteases MMP9 and MMP2. Many of these proteins are involved in the process of epithelial to mesenchymal transition, which is considered as a critical step in the progression of noninvasive tumor cells into malignant, metastatic carcinomas. We therefore propose that EEB from Salix aegyptiaca is a potent nutraceutical causing cancer chemoprevention by inhibiting epithelial to mesenchymal transition and can be consumed for its health promoting effects.

Lysosomal alkalinization in nutrient restricted cancer cells activates cytoskeletal rearrangement to enhance partial epithelial to mesenchymal transition.

INTRODUCTION: Nutrient restriction in cancer cells can activate a number of stress response pathways for cell survival. We aimed to determine mechanistically how nutrient depletion in colorectal cancer (CRC) cells leads to cellular adaptation. MATERIALS AND METHODS: Cell survival under nutrient depletion (ND) was evaluated by colony formation and in vivo tumor formation assays. Lysosomes are activated with ND; therefore, we incubated the ND cells with the V-ATPase inhibitor Bafilomycin A1 (ND+Baf). The expression of epithelial and mesenchymal markers with ND+Baf was determined by RNA sequencing and RT-qPCR while motility was determined with an in vivo Chorioallantoic membrane (CAM) assay. Reorganization of cytoskeletal network and lysosomal positioning was determined by immunocytochemistry. RESULTS: 4 different colorectal cancer (CRC) cell lines under ND showed high viability, tumor forming ability and increased expression of one or more epithelial and mesenchymal markers, suggesting the activation of partial (p)-EMT. We observed a further increase in p-EMT markers, numerous membrane protrusions, decreased cell-cell adhesion in 3D, and increased motility in ND+Baf cells. The protrusions in the ND+Baf cells were primarily mediated by microtubules and enabled the relocalization of lysosomes from the perinuclear region to the periphery. CONCLUSIONS: ND activated p-EMT in CRC cells, which was exacerbated by lysosomal alkalinization. The ND+Baf cells also showed numerous protrusions containing lysosomes, which may lead to lysosomal exocytosis and enhanced motility.

MTA-1 expression is associated with metastasis and epithelial to mesenchymal transition in colorectal cancer cells.

Although metastasis associated protein 1 (MTA1) has been widely linked to tumor metastasis, the relevant mechanisms remain to be elucidated, especially in colorectal cancer (CRC). Here, we have investigated the link between MTA1, metastasis and epithelial-mesenchymal transition (EMT) in CRC. Eighteen normal colon tissues and 91 resected tumor samples were analyzed for MTA1 expression by immunohistochemistry (IHC). IHC indicated low or no nuclear MTA1 expression in the normal tissues and significantly higher expression in Grade II, Grade III and liver metastasis tumors. No statistically significant difference was observed in MTA1 expression between Grade III and liver metastatic tumors. To demonstrate the functional importance of MTA1 in vitro, the gene was silenced in HCT-116 cells and LoVo cells and overexpressed in HCT-116 cells. MTA1 overexpression in HCT-116 cells enhanced proliferation, adhesion to fibronectin, motility, migration, invasion through Matrigel, anchorage-independent growth, neoangiogenesis and induced a loss of apoptosis. Silencing of MTA1 resulted in a reversal of all of these features. Mechanistically, MTA1 silencing caused an increase in the epithelial markers E-cadherin and ZO-1 and a decrease in the mesenchymal marker vimentin while MTA1 overexpression caused an increase in vimentin expression. Moreover, MTA1 enhanced the expression of Snai1 and Slug; silencing of MTA1 reduced their recruitment to the promoter of E-cadherin, thereby leading to its expression. MTA1 is highly expressed in higher grade tumors and is important in the orchestration of various phenotypic changes in CRC, most likely by inducing EMT. This further corroborates its role as a master regulator in tumorigenesis.

Anticarcinogenic effects of the ethanolic extract of Salix aegyptiaca in colon cancer cells: involvement of Akt/PKB and MAPK pathways.

The bark from Salix species of plants has been traditionally consumed for its antiinflammatory properties. Because inflammation frequently accompanies the progress of colorectal cancer (CRC), we have evaluated the anticancer properties of the ethanolic extract from the bark (EEB) of S. aegyptiaca, a Salix species endogenous to the Middle East, using HCT-116 and HT29 CRC cell lines. Fresh bark from S. aegyptiaca was extracted with ethanol, fractionated by solvent-solvent partitioning and the fractions were analyzed by tandem mass spectrometry. Catechin, catechol, and salicin were the most abundant constituents of the extract. Interestingly, EEB showed the highest anticancer effect in the colon cancer cells followed by its fractions in ethyl acetate and water, with catechin, catechol, and salicin showing the least efficacy. EEB could strongly reduce the proliferation of the cancer cells, but not of CCD-18Co, normal colon fibroblast cell line. Accompanying this was cell cycle arrest at G1/S independent of DNA damage in the cancer cells, induction of apoptosis through a p53 dependent pathway and an inhibition of PI3K/Akt and MAP Kinase pathways at levels comparable to known commercial inhibitors. We propose that the combination of the polyphenols and flavonoids in EEB contributes toward its potent anticarcinogenic effects. [Supplementary materials are available for this article. Go to the publisher's online edition of Nutrition and Cancer for the following free supplemental resource(s): Supplementary Figure 1 and Supplementary Figure 2.].

The indispensability of macrophage adaptor proteins in chronic inflammatory diseases.

Adaptor proteins represent key signalling molecules involved in regulating immune responses. The host's innate immune system recognizes pathogens via various surface and intracellular receptors. Adaptor molecules are centrally involved in different receptor-mediated signalling pathways, acting as bridges between the receptors and other molecules. The presence of adaptors in major signalling pathways involved in the pathogenesis of various chronic inflammatory diseases has drawn attention toward the role of these proteins in such diseases. In this review, we summarize the importance and roles of different adaptor molecules in macrophage-mediated signalling in various chronic disease states. We highlight the mechanistic roles of adaptors and how they are involved in protein-protein interactions (PPI) via different domains to carry out signalling. Hence, we also provide insights into how targeting these adaptor proteins can be a good therapeutic strategy against various chronic inflammatory diseases.