The organ microenvironment and cancer metastasis

Nontargeted Identification of Organic Components in Fine Particulate Matter Related to Lung Tumor Metastasis Based on an Adverse Outcome Pathway Strategy

Emerging studies implicate fine particulate matter (PM2.5) and its organic components (OCs) as urgent hazard factors for lung cancer progression in nonsmokers. Establishing the adverse outcome pathway (AOP)-directed nontargeted identification method, this study aimed to explore whether PM2.5 exposure in coal-burning areas promoted lung tumor metastasis and how we identify its effective OCs to support traceability and control of regional PM2.5 pollution. First, we used a nude mouse model of lung cancer for PM2.5 exposure and found that the exposure significantly promoted the hematogenous metastases of A549-Luc cells in lung tissues and the adverse outcomes (AOs), with key events (KEs) including the changed expression of epithelial-mesenchymal transition (EMT) markers, such as suppression of E-cad and increased expression of Fib. Subsequently, using AOs and KEs as adverse outcome directors, we identified a total of 35 candidate chemicals based on the in vitro model and nontargeted analysis. Among them, tributyl phosphate (C12H27O4P), 2-bromotetradecane (C14H29Br), and methyl decanoate (C11H22O2) made greater contributions to the AOs. Finally, we clarified the interactions between these OCs and EMT-activating transcription factors (EMT-ATFs) as the molecular initiation event (MIE) to support the feasibility of the above identification strategy. The present study updates a new framework for identifying tumor metastasis-promoting OCs in PM2.5 and provides solid data for screening out chemicals that need priority control in polluted areas posing higher lung cancer risk.

Metastatic cells exploit their stoichiometric niche in the network of cancer ecosystems

Metastasis is a nonrandom process with varying degrees of organotropism-specific source-acceptor seeding. Understanding how patterns between source and acceptor tumors emerge remains a challenge in oncology. We hypothesize that organotropism results from the macronutrient niche of cells in source and acceptor organs. To test this, we constructed and analyzed a metastatic network based on 9303 records across 28 tissue types. We found that the topology of the network is nested and modular with scale-free degree distributions, reflecting organotropism along a specificity/generality continuum. The variation in topology is significantly explained by the matching of metastatic cells to their stoichiometric niche. Specifically, successful metastases are associated with higher phosphorus content in the acceptor compared to the source organ, due to metabolic constraints in proliferation crucial to the invasion of new tissues. We conclude that metastases are codetermined by processes at source and acceptor organs, where phosphorus content is a limiting factor orchestrating tumor ecology.

MicroRNAs, long non-coding RNAs, and circular RNAs and gynecological cancers: focus on metastasis

Gynecologic cancer is a significant cause of death in women worldwide, with cervical cancer, ovarian cancer, and endometrial cancer being among the most well-known types. The initiation and progression of gynecologic cancers involve a variety of biological functions, including angiogenesis and metastasis-given that death mostly occurs from metastatic tumors that have invaded the surrounding tissues. Therefore, understanding the molecular pathways underlying gynecologic cancer metastasis is critical for enhancing patient survival and outcomes. Recent research has revealed the contribution of numerous non-coding RNAs (ncRNAs) to metastasis and invasion of gynecologic cancer by affecting specific cellular pathways. This review focuses on three types of gynecologic cancer (ovarian, endometrial, and cervical) and three kinds of ncRNAs (long non-coding RNAs, microRNAs, and circular RNAs). We summarize the detailed role of non-coding RNAs in the different pathways and molecular interactions involved in the invasion and metastasis of these cancers.

Peritoneal Gene Transfection of Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand for Tumor Surveillance and Prophylaxis

Peritoneal metastasis is very common in gastrointestinal, reproductive, and genitourinary tract cancers in late stages or postsurgery, causing poor prognosis, so effective and nontoxic prophylactic strategies against peritoneal metastasis are highly imperative. Herein, we demonstrate the first gene transfection as a nontoxic prophylaxis preventing peritoneal metastasis or operative metastatic dissemination. Lipopolyplexes of TNF-related-apoptosis-inducing-ligand (TRAIL) transfected peritonea and macrophages to express TRAIL for over 15 days. The expressed TRAIL selectively induced tumor cell apoptosis while exempting normal tissue, providing long-term tumor surveillance. Therefore, tumor cells inoculated in the pretransfected peritoneal cavity quickly underwent apoptosis and, thus, barely formed tumor nodules, significantly prolonging the mouse survival time compared with chemotherapy prophylaxis. Furthermore, lipopolyplex transfection showed no sign of toxicity. Therefore, this peritoneal TRAIL-transfection is an effective and safe prophylaxis, preventing peritoneal metastasis.

Assessing Whether Morphological Changes in Axillary Lymph Node Have Already Occurred Prior to Metastasis in Breast Cancer Patients by Ultrasound

Background and Objectives: Whether the morphological changes in axillary lymph node (ALN) have occurred prior to metastasis remains unclear in breast cancer (BC) patients. The aim of this study is to investigate the influence of BC for the morphology of non-metastasis ALN (N−) and, further, to improve the performance of ultrasound (US) examination for metastasis ALN (N+). Materials and Methods: In this retrospective study, 653 patients with breast mass were enrolled and divided into normal group of 202 patients with benign breast tumor, N− group of 233 BC patients with negative ALN and N+ group of 218 BC patients with positive ALN. US features of ALN were evaluated and analyzed according to long (L) and short (S) diameter, the (L/S) axis ratio, cortical thickness, lymph node edge, replaced hilum and color Doppler flow imaging (CDFI). Results: ALN US features of short diameter, replaced hilum, cortical thickness and CDFI have significant statistical differences in N− group comparing with normal group and N+ group, respectively (p < 0.05). Conclusions: Therefore, BC can affect ALN and lead to US morphological changes whether lymph node metastasis is present, which reduces the sensitivity of axillary US. The combination of US and other examination methods should be applied to improve the diagnostic performance of N+.

Cell Metabolomics Reveals the Potential Mechanism of Aloe Emodin and Emodin Inhibiting Breast Cancer Metastasis

Metastasis is one of the main obstacles for the treatment and prognosis of breast cancer. In this study, the effects and possible mechanisms of aloe emodin (AE) and emodin (EMD) for inhibiting breast cancer metastasis were investigated via cell metabolomics. First, a co-culture model of MCF-7 and HUVEC cells was established and compared with a traditional single culture of MCF-7 cells. The results showed that HUVEC cells could promote the development of cancer cells to a malignant phenotype. Moreover, AE and EMD could inhibit adhesion, invasion, and angiogenesis and induce anoikis of MCF-7 cells in co-culture model. Then, the potential mechanisms behind AE and EMD inhibition of MCF-7 cell metastasis were explored using a metabolomics method based on UPLC-Q-TOF/MS multivariate statistical analysis. Consequently, 27 and 13 biomarkers were identified in AE and EMD groups, respectively, including polyamine metabolism, methionine cycle, TCA cycle, glutathione metabolism, purine metabolism, and aspartate synthesis. The typical metabolites were quantitatively analyzed, and the results showed that the inhibitory effect of AE was significantly better than EMD. All results confirmed that AE and EMD could inhibit metastasis of breast cancer cells through different pathways. Our study provides an overall view of the underlying mechanisms of AE and EMD against breast cancer metastasis.

Fluid shear stress influences invasiveness of HeLa cells through the induction of autophagy

Extravasation of metastatic cells from the blood or lymphatic circulation and formation of secondary tumor at a distant site is a key step of cancer metastasis. In this study, we report the role of hemodynamic shear stresses in fostering the release of pro-extravasation factors through the mediation of autophagy in cervical cancer HeLa cells. HeLa cells were exposed to physiological shear stress through the microfluidic approach adapted in our previous study on the role of hemodynamic shear stresses in survival of HeLa cells. Herein, an optimum number of passes through a cylindrical microchannel was chosen such that the viability of cells was unaffected by shear. Shear-exposed cells were then probed for their invasive and migratory potential through in vitro migration and invasion assays. The dependence of cancer cells on mechanically-induced autophagy for extravasation was further assessed through protein expression studies. Our results suggest that shear stress upregulates autophagy, which fosters paxillin turnover thereby leading to enhanced focal adhesion disassembly and in turn enhanced cell migration. Concurrently, shear stress-induced secretion of pro-invasive factors like MMP-2 and IL-6 were found to be autophagy-dependent thereby hinting at autophagy as a potential therapeutic target in metastatic cancer. Proposed model for mechano-autophagic modulation of extravasation.

Radiosensitivity of Breast Cancer Cells Is Dependent on the Organ Microenvironment

Background

Distant metastasis is the leading risk factor of death in breast cancer patients, with lung and liver being commonly involved sites of distant seeding. Ongoing clinical trials are studying the benefit from additional local treatment to these metastatic sites with radiation therapy. However, little is known about the tissue-specific microenvironment and the modulating response to treatments due to limitations of traditional in vitro systems. By using biomatrix scaffolds (BMSs) to recreate the complex composition of extracellular matrices in normal organs, we chose to study the radiotherapy response with engineered breast cancer “metastases” in liver and lung organ-specific tissues.

Methods

Liver and lung BMSs were prepared for tissue culture. Human breast cancer cell lines were passaged on normal tissue culture plates or tissue culture plates coated with Matrigel, liver BMSs, and lung BMSs. Clonogenic assays were performed to measure cell survival with varying doses of radiation. Reactive Oxygen Species (ROS) detection assay was used to measure ROS levels after 6 Gy irradiation to cancer cells.

Results

The response of breast cell lines to varying doses of radiotherapy is affected by their in vitro acellular microenvironment. Breast cancer cells grown in liver BMSs were more radiosensitive than when grown in lung BMSs. ROS levels for breast cancer cells cultured in lung and liver BMSs were higher than that in plastic or in Matrigel plate cells, before and after radiotherapy, highlighting the interaction with surrounding tissue-specific growth factors and cytokines. ROSs in both lung and liver BMSs were significantly increased after radiotherapy delivery, suggesting these sites create prime environments for radiation-induced cell death.

Conclusions

The therapeutic response of breast cancer metastases is dependent on the organ-specific microenvironment. The interaction between tissue microenvironment in these organs may identify sensitivity of therapeutic drug targets and radiation delivery for future studies.

Integrated proteogenomic analysis revealed the metabolic heterogeneity in noncancerous liver tissues of patients with hepatocellular carcinoma

Understanding the adjacent liver microenvironment of hepatocellular carcinoma (HCC) with possible metastasis tendency might provide a strategy for risk classification of patients and potential therapies by converting the unique metastasis-inclined microenvironment to a metastasis-averse one. In this study, we performed an integrated proteogenomic analysis to have a comprehensive view on the heterogeneity of hepatic microenvironment contributing to HCC metastasis. Pairing mRNA-protein analysis revealed consistent and discordant mRNA-protein expressions in metabolism regulations and cancer-related pathways, respectively. Proteomic profiling identified three subgroups associated with the recurrence-free survival of patients. These proteomic subgroups demonstrated distinct features in metabolic reprogramming, which was potentially modified by epigenetic alterations. This study raises the point of metabolic heterogeneity in HCC noncancerous tissues and may offer a new perspective on HCC treatment.

Seeding metastases: The role and clinical utility of circulating tumour cells

Peripheral human blood is a readily-accessible source of patient material in which circulating tumour cells (CTCs) can be found. Their isolation and characterization holds the potential to provide prognostic value for various solid cancers. Enumeration of CTCs from blood is becoming a common practice in informing prognosis and may guide therapy decisions. It is further recognized that enumeration alone does not capture perspective on the heterogeneity of tumours and varying functional abilities of the CTCs to interact with the secondary microenvironment. Characterizing the isolated CTCs further, in particular assessing their functional abilities, can track molecular changes in the disease progress. As a step towards identifying a suite of functional features of CTCs that could aid in clinical decisions, developing a CTC isolation technique based on extracellular matrix (ECM) interactions may provide a more solid foundation for isolating the cells of interest. Techniques based on size, charge, density, and single biomarkers are not sufficient as they underutilize other characteristics of cancer cells. The ability of cancer cells to interact with ECM proteins presents an opportunity to utilize their full character in capturing, and also allows assessment of the features that reveal how cells might behave at secondary sites during metastasis. This article will review some common techniques and recent advances in CTC capture technologies. It will further explore the heterogeneity of the CTC population, challenges they experience in their metastatic journey, and the advantages of utilizing an ECM-based platform for CTC capture. Lastly, we will discuss how tailored ECM approaches may present an optimal platform to capture an influential heterogeneous population of CTCs.

Recent Advances in Phenolic Metabolites and Skin Cancer

Skin cancer represents any tumor development from the cutaneous structures within the epidermis, dermis or subcutaneous tissue, and is considered to be the most prevalent type of cancer. Compared to other types of cancer, skin cancer is proven to have a positive growth rate of prevalence and mortality. There are available various treatments, including chemotherapy, immunotherapy, radiotherapy and targeted therapy, but because of the multidrug resistance development, a low success has been registered. By this, the importance of studying naturally occurring compounds that are both safe and effective in the chemoprevention of skin cancer is emphasized. This review focuses on melanoma because it is the deadliest form of skin cancer, with a significantly increasing incidence in the last decades. As chemopreventive agents, we present polyphenols and their antioxidant activity, anti-inflammatory effect, their ability to balance the cell cycle and to induce apoptosis and their various other effects on skin melanoma. Besides chemoprevention, studies suggest that polyphenols can have treating abilities in some conditions. The limitations of using polyphenols are also pointed out, which are related to their poor bioavailability and stability, but as the technology is well developed, it is possible to augment the efficacy of polyphenols in the case of melanoma.

Combinatorial therapy in tumor microenvironment: Where do we stand?

The tumor microenvironment plays a pivotal role in tumor initiation and progression by creating a dynamic interaction with cancer cells. The tumor microenvironment consists of various cellular components, including endothelial cells, fibroblasts, pericytes, adipocytes, immune cells, cancer stem cells and vasculature, which provide a sustained environment for cancer cell proliferation. Currently, targeting tumor microenvironment is increasingly being explored as a novel approach to improve cancer therapeutics, as it influences the growth and expansion of malignant cells in various ways. Despite continuous advancements in targeted therapies for cancer treatment, drug resistance, toxicity and immune escape mechanisms are the basis of treatment failure and cancer escape. Targeting tumor microenvironment efficiently with approved drugs and combination therapy is the solution to this enduring challenge that involves combining more than one treatment modality such as chemotherapy, surgery, radiotherapy, immunotherapy and nanotherapy that can effectively and synergistically target the critical pathways associated with disease pathogenesis. This review shed light on the composition of the tumor microenvironment, interaction of different components within tumor microenvironment with tumor cells and associated hallmarks, the current status of combinatorial therapies being developed, and various growing advancements. Furthermore, computational tools can also be used to monitor the significance and outcome of therapies being developed. We addressed the perceived barriers and regulatory hurdles in developing a combinatorial regimen and evaluated the present status of these therapies in the clinic. The accumulating depth of knowledge about the tumor microenvironment in cancer may facilitate further development of effective treatment modalities. This review presents the tumor microenvironment as a sweeping landscape for developing novel cancer therapies.

Podocalyxin in Normal Tissue and Epithelial Cancer

Podocalyxin (PODXL), a glycosylated cell surface sialomucin of the CD34 family, is normally expressed in kidney podocytes, vascular endothelial cells, hematopoietic progenitors, mesothelium, as well as a subset of neurons. In the kidney, PODXL functions primarily as an antiadhesive molecule in podocyte epithelial cells, regulating adhesion and cell morphology, and playing an essential role in the development and function of the organ. Outside the kidney, PODXL plays subtle roles in tissue remodelling and development. Furthermore, many cancers, especially those that originated from the epithelium, have been reported to overexpress PODXL. Collective evidence suggests that PODXL overexpression is linked to poor prognosis, more aggressive tumour progression, unfavourable treatment outcomes, and possibly chemoresistance. This review summarises our current knowledge of PODXL in normal tissue function and epithelial cancer, with a particular focus on its underlying roles in cancer metastasis, likely involvement in chemoresistance, and potential use as a diagnostic and prognostic biomarker.

Ca2+ Signaling as the Untact Mode during Signaling in Metastatic Breast Cancer

Metastatic features of breast cancer in the brain are considered a common pathology in female patients with late-stage breast cancer. Ca2+ signaling and the overexpression pattern of Ca2+ channels have been regarded as oncogenic markers of breast cancer. In other words, breast tumor development can be mediated by inhibiting Ca2+ channels. Although the therapeutic potential of inhibiting Ca2+ channels against breast cancer has been demonstrated, the relationship between breast cancer metastasis and Ca2+ channels is not yet understood. Thus, we focused on the metastatic features of breast cancer and summarized the basic mechanisms of Ca2+-related proteins and channels during the stages of metastatic breast cancer by evaluating Ca2+ signaling. In particular, we highlighted the metastasis of breast tumors to the brain. Thus, modulating Ca2+ channels with Ca2+ channel inhibitors and combined applications will advance treatment strategies for breast cancer metastasis to the brain.

Combustion-derived particles from biomass sources differently promote epithelial-to-mesenchymal transition on A549 cells

Combustion-derived particles (CDPs), due to the presence in their composition of several toxic and carcinogenic chemical compounds, such as polycyclic aromatic hydrocarbons (PAHs) and metals, are linked to several respiratory diseases, including lung cancer. Epithelial-to-mesenchymal transition (EMT) is a crucial step in lung cancer progression, involving several morphological and phenotypical changes. The study aims to investigate how exposure to CDPs from different biomass sources might be involved in cancer development, focusing mainly on the effects linked to EMT and invasion on human A549 lung cells. Biomass combustion-derived particles (BCDPs) were collected from a stove fuelled with pellet, charcoal or wood, respectively. A time course and dose response evaluation on cell viability and pro-inflammatory response was performed to select the optimal conditions for EMT-related studies. A significant release of IL-8 was found after 72 h of exposure to 2.5 μg/cm² BCDPs. The EMT activation was then examined by evaluating the expression of some typical markers, such as E-cadherin and N-cadherin, and the possible enhanced migration and invasiveness. Sub-acute exposure revealed that BCDPs differentially modulated cell viability, migration and invasion, as well as the expression of proteins linked to EMT. Results showed a reduction in the epithelial marker E-cadherin and a parallel increase in the mesenchymal markers N-cadherin, mainly after exposure to charcoal and wood. Migration and invasion were also increased. In conclusion, our results suggest that BCDPs with a higher content of organic compounds (e.g. PAHs) in their chemical composition might play a crucial role in inducing pro-carcinogenic effects on epithelial cells.

Combination of canstatin and arsenic trioxide suppresses the development of hepatocellular carcinoma

Complication of arsenic trioxide (ATO) and other drugs in cancer treatment has attracted much focus, but is limitedly investigated in hepatocellular carcinoma (HCC). This study aimed to explore the role of ATO combined with canstatin in HCC. HepG2 cells were treated with different concentrations of ATO with or without canstatin, CCK-8, flow cytometry, Transwell assays were conducted to determine cell proliferation, apoptosis, adhesion, migration, and invasion abilities. Besides, the protein expression or mRNA level of caspase-3, PCNA, and MMP-2 was measured using western blotting or qRT-PCR. BALB/c-nu/nu mice were used to establish nude mouse transplantation tumor model, and received ATO or canstatin treatment for 3 weeks. The results showed that ATO inhibited cell proliferation, adhesion, migration and invasion, and promoted cell apoptosis with a concentration-dependent way. Canstatin had a significantly inhibitory effect on cell proliferation, but had limited effects on the other cellular behaviors. Besides, combination with ATO and canstatin strengthened the effects of ATO alone on cell proliferation inhibition and cell apoptosis promotion. Moreover, both of ATO and canstatin increased the protein expression of caspase-3, while decreased PCNA and MMP-2, which was further strengthened upon their combination. Furthermore, both of ATO and canstatin inhibited tumor growth in vivo, which was also strengthened upon their combination. Collectively, we found that combined canstatin and ATO significantly inhibited cell proliferation, migration and adhesion abilities, and promoted cell apoptosis, and inhibited tumor growth, thus suppressed the progression of HCC.

Molecular dynamics simulation, free energy landscape and binding free energy computations in exploration the anti-invasive activity of amygdalin against metastasis

BACKGROUND AND OBJECTIVE

Historically, amygdalin has been used as alternative medicine or in vitro and in vivo studies, but no single study exists which discusses the structural mechanism of amygdalin at a molecular level. This paper inquiries into the inhibitory actions of amygdalin on the selected targets: AKT1, FAK, and ILK, which are regulators for various mediated signaling pathways, and are associated with cell adhesion, migration, and differentiation. In order to get details at the molecular level of amygdalin's inhibitory activities against chosen proteins, molecular modeling and simulation techniques including double docking, molecular dynamics simulation, free energy landscape analysis, and binding free energy calculation were exerted.

METHODS

To get molecular level details of amygdalin inhibitory effects against the relevant proteins; here the utilized tools are the following: the double docking, molecular dynamics simulation, free energy landscape analysis, g_mmpbsa, and interaction entropy were used to evaluate the inhibitory activity against targeted proteins.

RESULTS

The computational calculations revealed that amygdalin inhibits the selected targets via block the ATP-binding pocket of AKT1, FAK, and ILK by forming stable hydrogen bonds. Moreover, free energy landscape, FEL exposed that amygdalin stabilized the global conformations of both FAK and ILK proteins to the minimum global energy besides it reduced the essential dynamics of FAK and ILK proteins. MMPBSA computations provided further evidence for amygdalin's stability inside the ATP-binding pocket of AKT1, FAK, and ILK with a binding free energy of 45.067, -13.033, 13.109 kJ/mol, respectively. The binding free energies are lastly consistent with the hydrogen bonding and pairs within 0.35 nm results. The decomposition of binding energy shows the pivotal amino acid residues responsible for the stability of amygdalin's interactions inside the ATP-binding sites by forming hydrogen bonds.

CONCLUSIONS

Before this work, it was enigmatic to make predictions about how amygdalin inhibits metastasis of cancer. But the computational results contribute in several ways to our understanding of amygdalin activity and provide a basic insight into the activity of amygdalin as a multi-target drug in the metastasis and invasion of cancer.

Circulating tumour cells: a broad perspective

Circulating tumour cells (CTCs) have recently been identified as valuable biomarkers for diagnostic and prognostic evaluations, as well for monitoring therapeutic responses to treatments. CTCs are rare cells which may be present as one CTC surrounded by approximately 1 million white blood cells and 1 billion red blood cells per millilitre of peripheral blood. Despite the various challenges in CTC detection, considerable progress in detection methods have been documented in recent times, particularly for methodologies incorporating nanomaterial-based platforms and/or integrated microfluidics. Herein, we summarize the importance of CTCs as biological markers for tumour detection, highlight their mechanism of cellular invasion and discuss the various challenges associated with CTC research, including vulnerability, heterogeneity, phenotypicity and size differences. In addition, we describe nanomaterial agents used for electrochemistry and surface plasmon resonance applications, which have recently been used to selectively capture cancer cells and amplify signals for CTC detection. The intrinsic properties of nanomaterials have also recently been exploited to achieve photothermal destruction of cancer cells. This review describes recent advancements and future perspectives in the CTC field.

Renin-Angiotensin System in Lung Tumor and Microenvironment Interactions

The mechanistic involvement of the renin-angiotensin system (RAS) reaches beyond cardiovascular physiopathology. Recent knowledge pinpoints a pleiotropic role for this system, particularly in the lung, and mainly through locally regulated alternative molecules and secondary pathways. Angiotensin peptides play a role in cell proliferation, immunoinflammatory response, hypoxia and angiogenesis, which are critical biological processes in lung cancer. This manuscript reviews the literature supporting a role for the renin-angiotensin system in the lung tumor microenvironment and discusses whether blockade of this pathway in clinical settings may serve as an adjuvant therapy in lung cancer.

Apolipoprotein(a), an enigmatic anti-angiogenic glycoprotein in human plasma: A curse or cure?

Angiogenesis is a finely co-ordinated, multi-step developmental process of the new vascular structure. Even though angiogenesis is regularly occurring in physiological events such as embryogenesis, in adults, it is restricted to specific tissue sites where rapid cell-turnover and membrane synthesis occurs. Both excessive and insufficient angiogenesis lead to vascular disorders such as cancer, ocular diseases, diabetic retinopathy, atherosclerosis, intra-uterine growth restriction, ischemic heart disease, stroke etc. Occurrence of altered lipid profile and vascular lipid deposition along with vascular disorders is a hallmark of impaired angiogenesis. Among lipoproteins, lipoprotein(a) needs special attention due to the presence of a multi-kringle protein subunit, apolipoprotein(a) [apo(a)], which is structurally homologous to many naturally occurring anti-angiogenic proteins such as plasminogen and angiostatin. Researchers have constructed different recombinant forms of apo(a) (rhLK68, rhLK8, RHACK2, KV-11, and AU-6) and successfully exploited its potential to inhibit unwanted angiogenesis during tumor metastasis and retinal neovascularization. Similar to naturally occurring anti-angiogenic proteins, apo(a) can directly interfere with angiogenic signaling pathways. Besides this, apo(a) can also exert its anti-angiogenic effect indirectly by inducing endothelial cell apoptosis, by inhibiting endothelial progenitor cell functions or by upregulating nuclear factors in endothelial cells via apo(a)-bound oxPLs. However, the impact of the anti-angiogenic potential of native apo(a) during physiological angiogenesis in embryos and wounded tissues is not yet explored. In this context, we review the studies so far done to demonstrate the anti-angiogenic activity of apo(a) and the recent developments in using apo(a) as a therapeutic agent to treat impaired angiogenesis during vascular disorders, with emphasis on the gaps in the literature.

Epithelial-Mesenchymal Transition Induces Podocalyxin to Promote Extravasation via Ezrin Signaling

The epithelial-mesenchymal transition (EMT) endows carcinoma cells with traits needed to complete many of the steps leading to metastasis formation, but its contributions specifically to the late step of extravasation remain understudied. We find that breast cancer cells that have undergone an EMT extravasate more efficiently from blood vessels both in vitro and in vivo. Analysis of gene expression changes associated with the EMT program led to the identification of an EMT-induced cell-surface protein, podocalyxin (PODXL), as a key mediator of extravasation in mesenchymal breast and pancreatic carcinoma cells. PODXL promotes extravasation through direct interaction of its intracellular domain with the cytoskeletal linker protein ezrin. Ezrin proceeds to establish dorsal cortical polarity, enabling the transition of cancer cells from a non-polarized, rounded cell morphology to an invasive extravasation-competent shape. Hence, the EMT program can directly enhance the efficiency of extravasation and subsequent metastasis formation through a PODXL-ezrin signaling axis.

Spz/Toll-6 signal guides organotropic metastasis in Drosophila

Targeted cell migration plays important roles in developmental biology and disease processes, including in metastasis. Drosophila tumors exhibit traits characteristic of human cancers, providing a powerful model to study developmental and cancer biology. We now find that cells derived from Drosophila eye-disc tumors also display organ-specific metastasis, invading receptive organs but not wing disc. Toll receptors are known to affect innate immunity and the tumor inflammatory microenvironment by modulating the NF-κB pathway. Our RNA interference (RNAi) screen and genetic analyses show that Toll-6 is required for migration and invasion of the tumor cells. Further, receptive organs express Toll ligands [Spätzle (Spz) family molecules], and ectopic Spz expression renders the wing disc receptive to metastasis. Finally, Toll-6 promotes metastasis by activating JNK signaling, a key regulator of cell migration. Hence, we report Toll-6 and Spz as a new pair of guidance molecules mediating organ-specific metastatic behavior and highlight a novel signaling mechanism for Toll-family receptors.

Ocoxin Oral Solution Exerts an Antitumoral Effect in Pancreatic Cancer and Reduces the Stromal-Mediated Chemoresistance

OBJECTIVES

Pancreatic carcinoma is one of the most aggressive cancers overcoming chemoresistance. Thus, novel compounds to complement the current antitumor agents are in need. Ocoxin oral solution (OOS) has proven antioxidant, anti-inflammatory, and antistromagenic properties. The aim of this study was to analyze the effect of OOS in an experimental pancreatic cancer model and its implication in stroma-related chemoresistance to paclitaxel and gemcitabine.

METHODS

Murine pancreatic carcinoma 266-6 cells were treated with OOS to analyze cell cycle and to perform a mRNA comparative microarray study. Then the viability was assessed in combination with paclitaxel and/or gemcitabine. Chemoresistance induced by the medium taken from fibroblast cultures was also investigated on 6 human pancreatic carcinoma cell lines. Furthermore, an experimental model of pancreatic cancer was carried out to study the effect of OOS in vivo.

RESULTS

Ocoxin oral solution enhances the cytotoxic effect of paclitaxel and gemcitabine, while it ameliorates the chemoresistance induced by fibroblast-derived soluble factors in human pancreatic cancer cells. The OOS also promotes the regulation of the expression of genes that are altered in pancreatic carcinoma and slows down 266-6 cell pancreatic tumor development in vivo.

CONCLUSIONS

Ocoxin oral solution could be a potential complement to the chemotherapeutic drugs for pancreatic adenocarcinoma.

Potential roles of reactive oxygen species derived from chemical substances involved in cancer development in the female reproductive system

Reactive oxygen species (ROS) are major sources of cellular oxidative stress. Specifically, cancer cells harbor genetic alterations that promote a continuous and elevated production of ROS. While such oxidative stress conditions could be harmful to normal cells, they facilitate cancer cell growth in multiple ways by causing DNA damage and genomic instability, and ultimately by reprogramming cancer cell metabolism. This review provides up to date findings regarding the roles of ROS generation induced by diverse biological molecules and chemicals in representative women’s cancer. Specifically, we describe the cellular signaling pathways that regulate direct or indirect interactions between ROS homeostasis and metabolism within female genital cancer cells.

Yifei Tongluo, a Chinese Herbal Formula, Suppresses Tumor Growth and Metastasis and Exerts Immunomodulatory Effect in Lewis Lung Carcinoma Mice

This study was aimed to investigate the anti-tumor, anti-metastasis and immunomodulatory effects of Yifei Tongluo (YFTL), a Chinese herbal formula, in Lewis lung carcinoma mice and to explore the underlying mechanisms. LLC cells were inoculated subcutaneously in C57BL/6 mice to establish the Lewis lung carcinoma model. We observed that YFTL effectively inhibited tumor growth and prolonged the overall survival of tumor-bearing mice. Additionally, YFTL treatment resulted in a significantly decreased number of surface lung metastatic lesions compared with the model control group. Meanwhile, TUNEL staining confirmed that the tumors from YFTL-treated mice exhibited a markedly higher apoptotic index. The results suggest that Akt and mitogen-activated protein kinase (MAPKs) pathways may be involved in YFTL-induced apoptosis. The results show that YFTL also inhibited the vascular endothelial growth factor (VEGF), matrix metalloproteinases (MMP)-2, MMP-9, N-cadherin, and Vimentin expression, but increased E-cadherin expression. Mechanistic studies indicated that YFTL could suppress the angiogenesis and the epithelial-mesenchymal transition (EMT) of the tumor through Akt/ERK1/2 and TGFβ1/Smad2 pathways. In addition, YFTL also showed immunomodulatory activities in improving the immunosuppressive state of tumor-bearing mice. Therefore, our findings could support the development of YFTL as a potential antineoplastic agent and a potentially useful anti-metastatic agent for lung carcinoma therapy.

Bulnesia sarmientoi Supercritical Fluid Extract Exhibits Necroptotic Effects and Anti-Metastatic Activity on Lung Cancer Cells

Bulnesia sarmientoi (BS) has long been used as an analgesic, wound-healing and anti-inflammatory medicinal plant. The aqueous extract of its bark has been demonstrated to have anti-cancer activity. This study investigated the anti-proliferative and anti-metastatic effects of BS supercritical fluid extract (BSE) on the A549 and H661 lung cancer cell lines. The cytotoxicity on cancer cells was assessed by an MTT assay. After 72 h treatment of A549 and H661 cells, the IC₅₀ values were 18.1 and 24.7 μg/mL, respectively. The cytotoxicity on MRC-5 normal cells was relatively lower (IC₅₀ = 61.1 μg/mL). BSE arrested lung cancer cells at the S and G₂/M growth phase. Necrosis of A549 and H661 cells was detected by flow cytometry with Annexin V-FITC/PI double staining. Moreover, the cytotoxic effect of BSE on cancer cells was significantly reverted by Nec-1 pretreatment, and BSE induced TNF-α and RIP-1 expression in the absence of caspase-8 activity. These evidences further support that BSE exhibited necroptotic effects on lung cancer cells. By wound healing and Boyden chamber assays, the inhibitory effects of BSE on the migration and invasion of lung cancer cells were elucidated. Furthermore, the chemical composition of BSE was examined by gas chromatography-mass analysis where ten constituents of BSE were identified. α-Guaiene, (−)-guaiol and β-caryophyllene are responsible for most of the cytotoxic activity of BSE against these two cancer cell lines. Since BSE possesses significant cytotoxicity and anti-metastatic activity on A549 and H661 cells, it may serve as a potential target for the treatment of lung cancer.

Acoustic impedance-based size-independent isolation of circulating tumour cells from blood using acoustophoresis

Label-free isolation of CTCs from blood is critical for the development of diagnostic and prognostic tools for cancer. Here, we report a label-free method based on acoustic impedance contrast for the isolation of CTCs from peripheral blood mononuclear cells (PBMCs) in a microchannel using acoustophoresis. We describe a method in which the acoustophoretic migration of PBMCs is arrested by matching their acoustic impedance with that of the sample medium, and CTCs that have different acoustic impedance compared to PBMCs migrate toward the pressure node or antinode and thus become isolated. We show that acoustic streaming which can adversely affect the CTC isolation is suppressed owing to the inhomogeneous liquid flow configuration. We establish a method for isolation of CTCs that have higher or lower acoustic impedance compared to PBMCs by controlling the acoustic impedance contrast of the liquids across the channel. Applying this method, we demonstrate label-free isolation of HeLa and MDA-MB-231 cells from PBMCs (collected from 2.0 mL of blood) within one hour yielding a recovery of >86% and >50-fold enrichment. Combined impedance and size-based sorting is proposed as a promising tool for the effective isolation of CTCs from blood.

Anti-cancer effects of 3,5-dimethylaminophenol in A549 lung cancer cells

Exposure to 3,5-dimethylaminophenol (3,5-DMAP), the metabolite of the 3-5-dimethylaniline, was shown to cause high levels of oxidative stress in different cells. The aim of the present work was to observe whether this metabolite can lead to cytotoxicity, oxidative stress, DNA damage and cell cycle changes in non-small cell lung cancer A549 cells. 3,5-DMAP caused a dose-dependent increase in cytotoxicity, generation of superoxide (O₂^-.), inductions in the enzyme activities orchestrating cellular antioxidant balance, increases in lipid peroxidation as well as DNA damage. However, 3,5-DMAP showed significantly lower cytotoxicity towards human lung fibroblast (HLF) cells. 3,5-DMAP also led to molecular events, like inducing apoptotic markers (ie. p53, Bad, Bax and cytochrome c); decreasing anti-apoptotic proteins (Bcl-2) and alterations in cell cycle. Our findings indicate that the cytotoxicity caused by this particular alkylaniline metabolite led to initiation of caspase 3-mediated apoptosis. Furthermore, 3,5-DMAP attenuated carcinogenic properties like migration capacity of A549 cells and eventually inhibited growth of A549 cells in an in vivo mouse model. Tumor sections showed that 3,5-DMAP down-regulated c-Myc expression but up-regulated p53 and cytochrome c, all of which might result in tumor growth arrest. Co-treatment with N-acetylcysteine provided reductions in cytotoxicity and positively modulated genetic events induced by 3,5-DMAP in A549 cells. In conclusion, our findings demonstrate 3,5-DMAP may be a potential anti-cancer drug in cancer, due to its self redox cycling properties.

Daphnane diterpenes inhibit the metastatic potential of B16F10 murine melanoma cells in vitro and in vivo

BACKGROUND

Melanoma is one of the most invasive and aggressive types of cancer with a very poor prognosis. Surgery remains the most efficient treatment prior melanoma invasion and metastasis formation. However, therapy becomes a challenge once the cancer cells colonized other tissues. At present, there are two main classes of therapies acting with a certain efficiency on metastatic melanoma: immune check point inhibitors (anti-PD1/PDL1) and targeted therapy such as Vemurafenib. Unfortunately, these therapies are not fully responsive, induce resistance and/or generate unwanted side effects. In this respect, it is important to continue to discover new cancer therapeutics. Here, we show that daphnane diterpenes type of compounds can prevent melanoma metastasis by inhibiting metastasis-associated matrix metalloproteinases expression without cytotoxicity.

METHODS

Evaluation of the anti-metastasis effect of daphnane diterpenes-rich Thymelaea hirsuta extract (TH) and its bioactive component gnidilatidin was carried out in vitro using B16 murine melanoma cells and in vivo using male C57BL/6 J mice. Global gene expression in B16 cells was done using DNA microarray, validated using real-time PCR, to further understand the effect of daphnane diterpenes, specifically daphnane diterpenoid gnidilatidin.

RESULTS

Oral administration of daphnane diterpenes-rich Thymelaea hirsuta extract (TH) suppressed MMP2 and MMP9 expression, decreasing lung tumor in mice injected with B16 murine melanoma cells. Validation of these observations in vitro showed reduced B16 cells migration, adhesion, and invasion. Results of microarray analysis of B16 cells treated with daphnane diterpenoid gnidilatidin from TH revealed an upregulation of tumor suppressor Egr1 while inhibiting metastasis-associated genes Id2 and Sytl2 expression. A downregulation of the melanoma oncogene microphthalmia-associated transcription factor (Mitf) was observed, and most likely caused by the inhibition of Id2, a gene that regulated HLH transcription factors such as MITF and also reported to promote tumor cell migration and invasion.

CONCLUSIONS

Daphnane diterpenes have inhibitory effect on the metastatic potential of B16 melanoma cells, and the results of this study provided evidence for their potential for use in the prevention and inhibition of melanoma metastasis.

An insight into metastasis: Random or evolving paradigms?

Mechanical or fostered molecular events define metastatic cascade. Three distinct sets of molecular events characterize metastasis, viz invasion of extracellular matrix; angiogenesis, vascular dissemination and anoikis resistance; tumor homing and relocation of tumor cells to selective organ. Invasion of extracellular matrix requires epithelial to mesenchymal transition through disrupted lamellopodia formation and contraction of actin cytoskeleton; aberration of Focal adhesion complex formation involving integrins and the extracellular matrix; degradation of extracellular matrix by matrix metalloproteases; faulty immune surveillance in tumor microenvironment and an upregulated proton efflux pump NHE1 in tumors. Vascular dissemination and anoikis resistance depend upon upregulation of integrins, phosphorylation of CDCP1, attenuated apoptotic pathways and upregulation of angiogenesis. Tumor homing depends on recruitment of mesenchymal stem cells, expression on chemokines and growth factors, upregulated stem cell renewal pathways. Despite of many potential challenges in curbing metastasis, future targeted therapies involving immunotherapy, stem cell engineered and oncolytic virus based therapy, pharmacological activation of circadian clock are held promising. To sum up, metastasis is a complex cascade of events and warrants detailed molecular understanding for development of therapeutic strategies.

Metastatic gynecologic malignancies: advances in treatment and management

Gynecologic cancers comprise of mostly uterine, ovarian, and cervical malignancies and are responsible for 95,000 new cases annually in the United States. Uterine cancer is the most common and the number of new cases and mortality has been increasing. Cervical cancer has decreased due to screening, early detection, and treatment of pre-invasive cancers. However, ovarian cancer remains the most lethal because of advanced stage at diagnosis and drug resistance. The metastatic spread pattern differs amongst these cancers, with uterine and cervical cancer found mostly in the primary organ and ovarian cancer disseminating throughout the peritoneum and upper abdomen at presentation. The primary treatment of ovarian cancer typically involves surgery followed by systemic therapy for more advanced disease. Previously, systemic chemotherapy with platinums, taxanes, doxorubicin, topotecan, and gemcitabine has been the standard in either upfront or recurrent setting. With molecular and genetic breakthroughs, we now have over eight new indications and five novel biologic therapies including antiangiogenics, poly ADP ribose polymerase inhibitors, and immunotherapies approved over the last 3 years. In this review, we will examine the biology of gynecologic cancer metastasis and focus on new treatment options for these cancers with a focus on ovarian cancer.

Organ-specific metastases obtained by culturing colorectal cancer cells on tissue-specific decellularized scaffolds

Metastatic disease remains the primary cause of mortality in cancer patients. Yet the number of available in vitro models to study metastasis is limited by challenges in the recapitulation of the metastatic microenvironment in vitro, and by difficulties in maintaining colonized-tissue specificity in the expansion and maintenance of metastatic cells. Here, we show that decellularized scaffolds that retain tissue-specific extracellular-matrix (ECM) components and bound signaling molecules enable, when seeded with colorectal cancer (CRC) cells, the spontaneous formation of three-dimensional cell colonies that histologically, molecularly and phenotypically resemble in vivo metastases. Lung and liver metastases obtained by culturing CRC cells on, respectively, liver and lung decellularized scaffolds retained their tissue-specific tropism when injected in mice. We also found that the engineered metastases contained signet ring cells, which has not previously been observed ex vivo. A culture system with tissue-specific decellularized scaffolds represents a simple and powerful approach for the study of organ-specific cancer metastases.

A 3D Microfluidic Model to Recapitulate Cancer Cell Migration and Invasion

We have developed a microfluidic-based culture chip to simulate cancer cell migration and invasion across the basement membrane. In this microfluidic chip, a 3D microenvironment is engineered to culture metastatic breast cancer cells (MX1) in a 3D tumor model. A chemo-attractant was incorporated to stimulate motility across the membrane. We validated the usefulness of the chip by tracking the motilities of the cancer cells in the system, showing them to be migrating or invading (akin to metastasis). It is shown that our system can monitor cell migration in real time, as compare to Boyden chambers, for example. Thus, the chip will be of interest to the drug-screening community as it can potentially be used to monitor the behavior of cancer cell motility, and, therefore, metastasis, in the presence of anti-cancer drugs.

Novel dual-targeting anti-proliferative dihydrotriazine-chalcone derivatives display suppression of cancer cell invasion and inflammation by inhibiting the NF-κB signaling pathway

Chalcones present in edible plants possess anti-cancer and anti-inflammatory properties, with the Michael acceptor moiety reported to be responsible for their biological activities. In this study, two novel dihydrotriazine-chalcone compounds previously identified to exert anti-proliferative effects through dual-targeting of dihydrofolate reductase (DHFR) and thioredoxin reductase (TrxR), were evaluated for their anti-invasive and anti-inflammatory abilities. At non-lethal concentrations, the compounds suppressed in vitro migration of MDA-MB-231 breast carcinoma cells, which was correlated with a dose-dependent downregulation of phorbol 12-myristate 13-acetate (PMA)-induced matrix metalloproteinase-9 (MMP-9) expression and secretion. At similar concentrations, these chalcone-based compounds suppressed expression of inflammatory mediators inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in lipopolysaccharides (LPS)-stimulated murine macrophage-like RAW 264.7 cells, as well as tumor necrosis factor alpha (TNF-α) in LPS-stimulated human monocytes isolated from healthy donors. Mechanistically, inhibition of cancer cell invasion and inflammation by the compounds were mediated through suppression of the nuclear factor-kappaB (NF-κB) signaling pathway, which corroborated with the reported mechanism of action of chalcones. Their abilities to target multiple biological mediators relevant to multi-step carcinogenesis and with bioactivities stronger than those of the parent chalcone scaffold have warranted dihydrotriazine-chalcone compounds as promising candidates for use in pharmacological intervention of aggressive cancers.

S-phase kinase-associated protein 2 is involved in epithelial-mesenchymal transition in methotrexate-resistant osteosarcoma cells

Osteosarcoma (OS), a common worldwide primary aggressive bone malignancy, arises from primitive transformed cells of mesenchymal origin and usually attacks adolescents and young adults. Methotrexate (MTX) is the anti-folate drug used as a pivotal chemotherapeutic agent in the treatment of OS. However, patients with OS often develop drug resistance, leading to poor treatment outcomes. In the present study, in order to explore the underlying mechanisms responsible for MTX resistance, we established MTX-resistant OS cells using the U2OS and MG63 cell lines and examined whether MTX-resistant OS cells underwent epithelial-mesenchymal transition (EMT) by Transwell assay, wound healing assay, MTT assay, RT-PCR and western blot analysis. We found that the viability of the MTX-resistant cells remained relatively unaltered following further treatment with MTX compared to the parental cells. The resistant cells appeared to possess a mesenchymal phenotype, with an elongated and more spindle-like shape, and acquired enhanced invasive, migratory and attachment abilities. The measurement of EMT markers also supported EMT transition in the MTX-resistant OS cells. Our result further demonstrated that the overexpression of S-phase kinase-associated protein 2 (Skp2) was closely involved in the resistance of OS cells to MTX and in the acquirement of EMT properties. Thus, the pharmacological inhibition of Skp2 may prove to be a novel therapeutic strategy with which to overcome drug resistance in OS.

A highly invasive subpopulation of MDA-MB-231 breast cancer cells shows accelerated growth, differential chemoresistance, features of apocrine tumors and reduced tumorigenicity in vivo

The acquisition of an invasive phenotype is a prerequisite for metastasization, yet it is not clear whether or to which extent the invasive phenotype is linked to other features characteristic of metastatic cells. We selected an invasive subpopulation from the triple negative breast cancer cell line MDA-MB-231, performing repeated cycles of preparative assays of invasion through Matrigel covered membranes. The invasive sub-population of MDA-MB-231 cells exhibits stronger migratory capacity as compared to parental cells confirming the highly invasive potential of the selected cell line. Prolonged cultivation of these cells did not abolish the invasive phenotype. ArrayCGH, DNA index quantification and karyotype analyses confirmed a common genetic origin of the parental and invasive subpopulations and revealed discrete structural differences of the invasive subpopulation including increased ploidy and the absence of a characteristic amplification of chromosome 5p14.1-15.33. Gene expression analyses showed a drastically altered expression profile including features of apocrine breast cancers and of invasion related matrix-metalloproteases and cytokines. The invasive cells showed accelerated proliferation, increased apoptosis, and an altered pattern of chemo-sensitivity with lower IC50 values for drugs affecting the mitotic apparatus. However, the invasive cell population is significantly less tumorigenic in orthotopic mouse xenografts suggesting that the acquisition of the invasive capacity and the achievement of metastatic growth potential are distinct events.

Emerging Roles of Electrospun Nanofibers in Cancer Research

This article reviews the recent progress of electrospun nanofibers in cancer research. It begins with a brief introduction to the emerging potential of electrospun nanofibers in cancer research. Next, a number of recent advances on the important features of electrospun nanofibers critical for cancer research are discussed including the incorporation of drugs, control of release kinetics, orientation and alignment of nanofibers, and the fabrication of 3D nanofiber scaffolds. This article further highlights the applications of electrospun nanofibers in several areas of cancer research including local chemotherapy, combinatorial therapy, cancer detection, cancer cell capture, regulation of cancer cell behavior, construction of in vitro 3D cancer model, and engineering of bone microenvironment for cancer metastasis. This progress report concludes with remarks on the challenges and future directions for design, fabrication, and application of electrospun nanofibers in cancer diagnostics and therapeutics.

Adipocyte-activated oxidative and ER stress pathways promote tumor survival in bone via upregulation of Heme Oxygenase 1 and Survivin

Metastatic tumor cells engage the local tumor microenvironment and activate specific pro-survival mechanisms to thrive and progress in the harsh bone marrow niche. Here we show that the major contributors to the survival of carcinoma cells that have colonized the bone marrow are the adipocyte-induced oxidative stress and ER stress pathways. We demonstrate that upon exposure to adipocyte-rich environments in vitro or in vivo, bone-trophic prostate and breast tumor cells upregulate the oxidative stress enzyme, HO-1. We also show that HO-1 levels are significantly increased in human metastatic prostate cancer tissues and that stable HO-1 overexpression in tumor cells promotes growth and invasiveness. Co-incident with the adipocyte-induced expression of HO-1, there is an upregulation of ER chaperone BIP and splicing of XBP1, indicating adipocyte-driven unfolded protein response, a process that we show to be sensitive to antioxidant treatment. Importantly, we also demonstrate that triggering of the oxidative stress and ER stress responses, or HO-1 induction by adipocyte exposure result in the activation of pro-survival pathways, involving survivin. Collectively, our findings reveal a new link between HO-1 and survivin expression in tumor cells, and provide a new insight into potentially targetable survival pathways in bone-metastatic disease.

Chimaphilin inhibits human osteosarcoma cell invasion and metastasis through suppressing the TGF-β1-induced epithelial-to-mesenchymal transition markers via PI-3K/Akt, ERK1/2, and Smad signaling pathways

Epithelial-to-mesenchymal transition is a cellular process associated with cancer invasion and metastasis. However, the antimetastatic effects of chimaphilin remain elusive. In this study, we attempted to investigate the potential use of chimaphilin as an inhibitor of TGF-β1-induced epithelial-to-mesenchymal transition in U2OS cells. We found that TGF-β1 induced epithelial-to-mesenchymal transition to promote U2OS cell invasion and metastasis. Western blotting demonstrated that chimaphilin inhibited U2OS cell invasion and migration, increased the expression of the epithelial phenotype marker E-cadherin, repressed the expression of the mesenchymal phenotype marker vimentin, as well as decreased the level of epithelial-to-mesenchymal-inducing transcription factors Snail1 and Slug during the initiation of TGF-β1-induced epithelial-to-mesenchymal transition. In this study, we revealed that chimaphilin up-regulated the E-cadherin expression level and inhibited the production of vimentin, Snail1, and Slug in TGF-β1-induced U2OS cells by blocking PI-3K/Akt and ERK 1/2 signaling pathway. Additionally, the TGF-β1-mediated phosphorylated levels of Smad2/3 were inhibited by chimaphilin pretreatment. Above all, we conclude that chimaphilin represents an effective inhibitor of the metastatic potential of U2OS cells through suppression of TGF-β1-induced epithelial-to-mesenchymal transition.

Smoking is a risk factor for pulmonary metastasis in colorectal cancer

AIM

The hepatic microenvironment, which may include chronic inflammation and fibrosis, is considered to contribute to the pathogenesis of liver metastases of colorectal cancer. A similar mechanism is anticipated for pulmonary metastases, although no reports are available. Smoking causes pulmonary inflammation and fibrosis. Thus, we hypothesized that smokers would be especially affected by pulmonary metastases of colorectal cancer. In this study, we attempted to clarify the impact of smoking on pulmonary metastasis of colorectal cancer.

METHOD

Between September 2005 and December 2010 we reviewed 567 patients with pathological Stage I, II or III colorectal cancer, whose clinicopathological background included a preoperative smoking history, pack-year history from medical records. Univariate and multivariate analyses using the Cox proportional hazard model were performed to determine the independent prognostic factors for pulmonary metastasis-free survival.

RESULTS

Pulmonary metastases occurred in 39 (6.9%) patients. The smoking histories revealed 355 never smokers, 119 former smokers and 93 current smokers among the subjects. Multivariate analysis revealed that being a current smoker (hazard ratio = 2.72, 95% CI 1.18-6.25; P = 0.02) was an independent risk factor for pulmonary metastases.

CONCLUSION

Smoking may be a risk factor for pulmonary metastasis of colorectal cancer. Cessation of smoking should be recommended to prevent pulmonary metastasis, although further basic and clinical studies are required.

Wound fluids affect miR-21, miR-155 and miR-221 expression in breast cancer cell lines, and this effect is partially abrogated by intraoperative radiation therapy treatment

Breast cancer is the most common malignant disease occurring in women. Conservative breast cancer surgery followed by radiation therapy is currently the standard treatment for this type of cancer. The majority of metastases occur within the scar, which initiated a series of studies. As a result, clinical trials aimed to assess whether localized radiotherapy, as intraoperative radiotherapy (IORT), may more effective in inhibiting the formation of local recurrence compared with the standard postoperative whole breast radiotherapy. The present study determined the role of postoperative wound fluids (WFs) from patients diagnosed with breast cancer subsequent to breast conserving surgery or breast conserving surgery followed by IORT on the expression of three microRNAs (miRNAs), consisting of miR-21, miR-155 and miR-221, in distinct breast cancer cell lines that represent the general subtypes of breast cancer. It was determined that the miRNAs responsible for breast cancer progression, induction of tumorigenesis and enrichment of the cancer stem cell phenotype, which is responsible for resistance to tumor therapy, were highly upregulated in the human epidermal growth factor receptor 2-positive breast cancer SK-BR-3 cell line following stimulation with WFs. It is worth emphasizing, that those changes were more significant in WFs collected from patients after surgery alone. The BT-549 cell line showed altered expression only of miR-155 following incubation with WFs. Notably, this change was not associated with IORT. Additionally, it was indicated that both WFs and RT-WF strongly downregulated the expression of miR-21, miR-155 and miR-221 in basal/epithelial and luminal subtypes of breast cancer. It was concluded that the present study contributes to an increased understanding of the role of surgical WFs and IORT treatment in the regulation of miRNA expression. This may enable the development of the current knowledge of breast cancer biology subsequent to IORT treatment and substantially to improve the therapy in the future.