Invasive Colon Cancer Cells Induce Transdifferentiation of Endothelium to Cancer-Associated Fibroblasts through Microtubules Enriched in Tubulin-β3

Exposure to trichloromethane via drinking water promotes progression of colorectal cancer by activating IRE1α/XBP1 pathway of endoplasmic reticulum stress

Trichloromethane (TCM), a commonly recognized disinfection by-product formed during the chlorination of water, has been associated with the onset of colorectal cancer (CRC) in humans. Despite this, the impact of TCM on the progression of CRC remains uncertain. In this investigation, it was observed that exposure to TCM could augment the migratory capabilities of CRC cells and facilitate the advancement of colorectal tumors. To delve deeper into the mechanism responsible for TCM-induced CRC progression, we performed RNA-Seq analysis at cellular and animal levels after TCM exposure. Both the KEGG and GO enrichment analyses indicated the activation of endoplasmic reticulum stress (ERS) and the regulation of the cytoskeleton. Subsequently, we confirmed the activation of the IRE1α/XBP1 pathway of ERS through western blot and RT-qPCR. Additionally, we observed the aggregation of cytoskeletal proteins F-actin and β-tubulin at the cell membrane periphery and the development of cellular pseudopods using immunofluorescence following exposure to TCM in vitro. The downregulation of IRE1α and XBP1 through siRNA interference resulted in the disruption of cell cytoskeleton rearrangement and impaired cell migration capability. Conversely, treatment with TCM mitigated this inhibitory effect. Moreover, chronic exposure to low concentration of TCM also triggered CRC cell migration by causing cytoskeletal reorganization, a process controlled by the IRE1α/XBP1 axis. Our study concludes that TCM exposure induces cell migration through the activation of ERS, which in turn regulates cytoskeleton rearrangement. This study offers novel insights into the mechanism through which TCM facilitates the progression of CRC.

Metastasis-associated fibroblasts in peritoneal surface malignancies

Over decades, peritoneal surface malignancies (PSMs) have been associated with limited treatment options and poor prognosis. However, advancements in perioperative systemic chemotherapy, cytoreductive surgery (CRS), and hyperthermic intraperitoneal chemotherapy (HIPEC) have significantly improved clinical outcomes. PSMs predominantly result from the spread of intra-abdominal neoplasia, which then form secondary peritoneal metastases. Colorectal, ovarian, and gastric cancers are the most common contributors. Despite diverse primary origins, the uniqueness of the peritoneum microenvironment shapes the common features of PSMs. Peritoneal metastization involves complex interactions between tumour cells and the peritoneal microenvironment. Fibroblasts play a crucial role, contributing to tumour development, progression, and therapy resistance. Peritoneal metastasis-associated fibroblasts (MAFs) in PSMs exhibit high heterogeneity. Single-cell RNA sequencing technology has revealed that immune-regulatory cancer-associated fibroblasts (iCAFs) seem to be the most prevalent subtype in PSMs. In addition, other major subtypes as myofibroblastic CAFs (myCAFs) and matrix CAFs (mCAFs) were frequently observed across PSMs studies. Peritoneal MAFs are suggested to originate from mesothelial cells, submesothelial fibroblasts, pericytes, endothelial cells, and omental-resident cells. This plasticity and heterogeneity of CAFs contribute to the complex microenvironment in PSMs, impacting treatment responses. Understanding these interactions is crucial for developing targeted and local therapies to improve PSMs patient outcomes.

The role of cancer-associated fibroblasts in the invasion and metastasis of colorectal cancer

Colorectal cancer (CRC) is the third most common cancer and has ranked the third leading cause in cancerassociated death globally. Metastasis is the leading cause of death in colorectal cancer patients. The role of tumor microenvironment (TME) in colorectal cancer metastasis has received increasing attention. As the most abundant cell type in the TME of solid tumors, cancer-associated fibroblasts (CAFs) have been demonstrated to have multiple functions in advancing tumor growth and metastasis. They can remodel the extracellular matrix (ECM) architecture, promote epithelial-mesenchymal transition (EMT), and interact with cancer cells or other stromal cells by secreting growth factors, cytokines, chemokines, and exosomes, facilitating tumor cell invasion into TME and contributing to distant metastasis. This article aims to analyze the sources and heterogeneity of CAFs in CRC, as well as their role in invasion and metastasis, in order to provide new insights into the metastasis mechanism of CRC and its clinical applications.

Bioinformatics analysis of MMP14+ myeloid cells affecting endothelial-mesenchymal transformation and immune microenvironment in glioma

Background

Gliomas, known for their complex and aggressive characteristics, are deeply influenced by the tumor microenvironment. Matrix metalloproteinases (MMPs) play a vital role in shaping this environment, presenting an opportunity for novel treatment strategies.

Methods

We collected six bulk RNA datasets, one single-cell RNA sequencing (scRNA-seq) dataset, and gene sets related to Matrix Metalloproteinases (MMPs), Endothelial-Mesenchymal Transformation (EndMT), and sprouting angiogenesis. We computed enrichment scores using Gene Set Variation Analysis (GSVA) and Single-sample Gene Set Enrichment Analysis (ssGSEA). To analyze immune infiltration, we employed the CIBERSORT method. Data analysis techniques included the log-rank test, Cox regression, Kruskal-Wallis test, and Pearson correlation. For single-cell data, we utilized tools such as Seurat and CellChat for dimensionality reduction, clustering, and cell communication analysis.

Results

1. MMP14 was identified as an independent prognostic marker, highly expressed in myeloid cells in recurrent glioblastoma, highlighting these cells as functionally significant. 2. C-C Motif Chemokine Ligand (CCL) signaling from MMP14+ myeloid cells was identified as a critical immune regulatory pathway, with high C-C Motif Chemokine Receptor 1 (CCR1) expression correlating with increased M2 macrophage infiltration and PD-L1 expression. 3. Patients with high MMP14 expression showed better responses to bevacizumab combined chemotherapy. 4. Signaling pathways involving Visfatin, VEGF, and TGFb, emanating from myeloid cells, significantly impact endothelial cells. These pathways facilitate EndMT and angiogenesis in gliomas. 5. Nicotinamide Phosphoribosyltransferase (NAMPT) showed a strong link with angiogenesis and EndMT, and its association with chemotherapy resistance and differential sensitivity to bevacizumab was evident.

Conclusions

MMP14+ myeloid cells are critical in promoting tumor angiogenesis via EndMT and in mediating immunosuppression through CCL signaling in glioblastoma. MMP14 and NAMPT serve as vital clinical indicators for selecting treatment regimens in recurrent glioma. The study suggests that a combined blockade of CCR1 and CD274 could be a promising therapeutic strategy.

Nudifloside, a Secoiridoid Glucoside Derived from Callicarpa nudiflora, Inhibits Endothelial-to-Mesenchymal Transition and Angiogenesis in Endothelial Cells by Suppressing Ezrin Phosphorylation

Callicarpa nudiflora is a traditional folk medicine in China used for eliminating stasis to subdue swelling. Several compounds from Callicarpa nudiflora have been proved to show anti-inflammatory, haemostasis, hepatitis, and anti-proliferative effects. Tumor endothelial cells play crucial roles in tumor-induced angiogenesis. Recently, it was demonstrated that ECs may be the important source of cancer associated fibroblasts (CAFs) through endothelial to mesenchymal transition (EndoMT). In this study, we evaluated the effects of nudifloside (NDF), a secoiridoid glucoside from Callicarpa Nudiflora, on TGF-β1-induced EndoMT and VEGF-induced angiogenesis, and the underlying mechanisms were also involved. It was found that NDF significantly inhibited enhanced migration, invasion and F-actin assembly in endothelial cells (ECs) exposed in TGF-β1. NDF obviously reversed expression of several biomarkers associated with EndoMT and recovered the morphological characteristics of ECs and tube-like structure induced by TGF-β1. Furthermore, treatment of NDF resulted in a significant destruction of VEGF-induced angiogenesis in vitro and ex vivo. Data from co-immunoprecipitation assay provided the evidence that Ezrin phosphorylation and the interaction with binding protein can be inhibited by NDF, which can be confirmed by data from Ezrin silencing assay. Collectively, the application of NDF inhibited TGF-β1-induced EndoMT and VEGF-induced angiogenesis in ECs by reducing Ezrin phosphorylation.

Endothelial-to-mesenchymal transition in tumour progression and its potential roles in tumour therapy

Tumour-associated endothelial cells (TECs) are a critical stromal cell type in the tumour microenvironment and play central roles in tumour angiogenesis. Notably, TECs have phenotypic plasticity, as they have the potential to transdifferentiate into cells with a mesenchymal phenotype through a process termed endothelial-to-mesenchymal transition (EndoMT). Many studies have reported that EndoMT influences multiple malignant biological properties of tumours, such as abnormal angiogenesis and tumour metabolism, growth, metastasis and therapeutic resistance. Thus, the value of targeting EndoMT in tumour treatment has received increased attention. In this review, we comprehensively explore the phenomenon of EndoMT in the tumour microenvironment and identify influencing factors and molecular mechanisms responsible for EndoMT induction. Furthermore, the pathological functions of EndoMT in tumour progression and potential therapeutic strategies for targeting EndoMT in tumour treatment are also discussed to highlight the pivotal roles of EndoMT in tumour progression and therapy.

N(14)-substituted evodiamine derivatives as dual topoisomerase 1/tubulin-Inhibiting anti-gastrointestinal tumor agents

Gastrointestinal tumor is an important factor threatening human health. Natural product-based drug discovery is a popular paradigm for expanding the chemical space and identifying new molecular entities that ameliorate human disease. Evodiamine-inspired medicinal chemistry presents therapeutic potential for treating tumors in different tissues via multi-target inhibition. Here, by focusing on the discovery of anti-gastrointestinal tumor drugs, a series of N(14) alkyl-substituted evodiamine derivatives were designed and synthesized. The structure-activity relationship studies culminated in the identification of the N(14)-propyl-substituted evodiamine analog 6b, which showed low nanomolar inhibitory activity against MGC-803 (IC₅₀ = 0.09 μM) and RKO (IC₅₀ = 0.2 μM) cell lines. Moreover, compound 6b was effective in inducing apoptosis, arresting the cell cycle in the G2/M phase, and inhibiting migration and invasion of MGC-803 and RKO cell lines in a dose-dependent manner in vitro. Further antitumor mechanism studies revealed that compound 6b significantly inhibited topoisomerase 1 (inhibition rate of 58.3% at 50 μM) and tubulin polymerization (IC₅₀ = 5.69 μM). Overall, compound 6b represents a promising dual topoisomerase 1/tubulin-targeting lead structure for the treatment of gastrointestinal tumor.

Roles of TGF-β signals in tumor microenvironment via regulation of the formation and plasticity of vascular system

Tumor cells evolve in tumor microenvironment composed of multiple cell types. Among these, endothelial cells (ECs) are the major players in tumor angiogenesis, which is a driver of tumor progression and metastasis. Increasing evidence suggests that ECs also contribute to tumor progression and metastasis as they modify their phenotypes to differentiate into mesenchymal cells through a process known as endothelial-mesenchymal transition (EndoMT). This plasticity of ECs is mediated by various cytokines, including transforming growth factor-β (TGF-β), and modulated by other stimuli depending on the cellular contexts. Recent lines of evidence have shown that EndoMT is involved in various steps of tumor progression, including tumor angiogenesis, intravasation and extravasation of cancer cells, formation of cancer-associated fibroblasts, and cancer therapy resistance. In this review, we summarize current updates on EndoMT, highlight the roles of EndoMT in tumor progression and metastasis, and underline targeting EndoMT as a potential therapeutic strategy.

Cancer-Associated Fibroblasts: The Origin, Biological Characteristics and Role in Cancer-A Glance on Colorectal Cancer

Simple Summary

Tumor microenvironment is a major contributor to tumor growth, metastasis and resistance to therapy. It consists of many cancer-associated fibroblasts (CAFs), which derive from different types of cells. CAFs detected in different tumor types are linked to poor prognosis, as in the case of colorectal cancer. Although their functions differ according to their subtype, their detection is not easy, and there are no established markers for such detection. They are possible targets for therapeutic treatment. Many trials are ongoing for their use as a prognostic factor and as a treatment target. More research remains to be carried out to establish their role in prognosis and treatment.

Abstract

The therapeutic approaches to cancer remain a considerable target for all scientists around the world. Although new cancer treatments are an everyday phenomenon, cancer still remains one of the leading mortality causes. Colorectal cancer (CRC) remains in this category, although patients with CRC may have better survival compared with other malignancies. Not only the tumor but also its environment, what we call the tumor microenvironment (TME), seem to contribute to cancer progression and resistance to therapy. TME consists of different molecules and cells. Cancer-associated fibroblasts are a major component. They arise from normal fibroblasts and other normal cells through various pathways. Their role seems to contribute to cancer promotion, participating in tumorigenesis, proliferation, growth, invasion, metastasis and resistance to treatment. Different markers, such as a-SMA, FAP, PDGFR-β, periostin, have been used for the detection of cancer-associated fibroblasts (CAFs). Their detection is important for two main reasons; research has shown that their existence is correlated with prognosis, and they are already under evaluation as a possible target for treatment. However, extensive research is warranted.

Cytoskeleton Reorganization in EndMT-The Role in Cancer and Fibrotic Diseases

Chronic inflammation promotes endothelial plasticity, leading to the development of several diseases, including fibrosis and cancer in numerous organs. The basis of those processes is a phenomenon called the endothelial–mesenchymal transition (EndMT), which results in the delamination of tightly connected endothelial cells that acquire a mesenchymal phenotype. EndMT-derived cells, known as the myofibroblasts or cancer-associated fibroblasts (CAFs), are characterized by the loss of cell–cell junctions, loss of endothelial markers, and gain in mesenchymal ones. As a result, the endothelium ceases its primary ability to maintain patent and functional capillaries and induce new blood vessels. At the same time, it acquires the migration and invasion potential typical of mesenchymal cells. The observed modulation of cell shape, increasedcell movement, and invasion abilities are connected with cytoskeleton reorganization. This paper focuses on the review of current knowledge about the molecular pathways involved in the modulation of each cytoskeleton element (microfilaments, microtubule, and intermediate filaments) during EndMT and their role as the potential targets for cancer and fibrosis treatment.

The Versatile Roles of Cancer-Associated Fibroblasts in Colorectal Cancer and Therapeutic Implications

The tumor microenvironment (TME) is populated by abundant cancer-associated fibroblasts (CAFs) that radically influence the disease progression across many cancers, including the colorectal cancer (CRC). In theory, targeting CAFs holds great potential in optimizing CRC treatment. However, attempts to translate the therapeutic benefit of CAFs into clinic practice face many obstacles, largely due to our limited understanding of the heterogeneity in their origins, functions, and mechanisms. In recent years, accumulating evidence has uncovered some cellular precursors and molecular markers of CAFs and also revealed their versatility in impacting various hallmarks of CRC, together helping us to better define the population of CAFs and also paving the way toward their future therapeutic targeting for CRC treatment. In this review, we outline the emerging concept of CAFs in CRC, with an emphasis on their origins, biomarkers, prognostic significance, as well as their functional roles and underlying mechanisms in CRC biology. At last, we discuss the prospect of harnessing CAFs as promising therapeutic targets for the treatment of patients with CRC.

Transforming Growth Factor-β: An Agent of Change in the Tumor Microenvironment

Transforming Growth Factor-β (TGF-β) is a key regulator of embryonic development, adult tissue homeostasis, and lesion repair. In tumors, TGF-β is a potent inhibitor of early stage tumorigenesis and promotes late stage tumor progression and metastasis. Here, we review the roles of TGF-β as well as components of its signaling pathways in tumorigenesis. We will discuss how a core property of TGF-β, namely its ability to change cell differentiation, leads to the transition of epithelial cells, endothelial cells and fibroblasts to a myofibroblastoid phenotype, changes differentiation and polarization of immune cells, and induces metabolic reprogramming of cells, all of which contribute to the progression of epithelial tumors.

Protective effects of SS-31 against SDHB suppression-mitochondrial dysfunction-EndMT axis-modulated CBT sclerosis and progression

Sclerosis variant in carotid body tumor (CBT) is characterized by extensive stromal sclerosis, which results in an uncommon pattern of growth that closely resembles that of an invasive malignant neoplasm. However, the clinical significance and the mechanism remains unclear. In this study, we provide evidence that SS-31 exerts protective effects against SDHB suppression-mitochondrial dysfunction-EndMT axis-modulated CBT sclerosis and progression. In human CBT specimens, sclerosis extent was consistently related to decreased recurrence-, death-, systematic metastasis-, and major adverse event-free survival, decreased SDHB expression, and aggravated EndMT. In human umbilical vein endothelial cells (HUVECs), SDHB KD aggravated hypoxia-induced EndMT, mitochondrial dysfunction and metabolic switch, while SS-31 treatment could significantly attenuate these changes caused by SDHB KD and hypoxia. In patient-derived xenograft (PDX) mice models of CBT, we also observed increased tumor growth speed and extent of EndMT, mitochondrial dysfunction, and metabolic switch in sclerosing carotid body tumor (SCBT) group than in conventional carotid body tumor (CCBT) group. And treating with SS-31 could significantly retard SCBT progression by rescuing the mitochondrial dysfunction-induced EndMT. Altogether, these results show that SDHB suppression-mitochondrial dysfunction-EndMT axis is a critical part of the CBT sclerosis and progression, while mitochondria-targeted drug SS-31 exerts an inhibitive effect on the above-mentioned axis, which opens new strategies to prevent and treat malignancies of CBT.

Endothelial-to-Mesenchymal Transition in Cancer

Cancer is one of the most important causes of morbidity and mortality worldwide. Tumor cells grow in a complex microenvironment constituted of immune, stromal, and vascular cells that supports growth, angiogenesis, and metastasis. Endothelial cells (ECs) are major components of the vascular microenvironment. These cells have been described for their plasticity and potential to transdifferentiate into mesenchymal cells through a process known as endothelial-to-mesenchymal transition (EndMT). This complex process is controlled by various factors, by which ECs convert into a phenotype characterized by mesenchymal protein expression and motile, contractile morphology. Initially described in normal heart development, EndMT is now identified in several pathologies, and especially in cancer. In this review, we highlight the process of EndMT in the context of cancer and we discuss it as an important adaptive process of the tumor microenvironment that favors tumor growth and dissemination but also resistance to treatment. Thus, we underline targeting of EndMT as a potential therapeutic strategy.

Mechanical tumor microenvironment and transduction: cytoskeleton mediates cancer cell invasion and metastasis

Metastasis is a complicated, multistep process that is responsible for over 90% of cancer-related death. Metastatic disease or the movement of cancer cells from one site to another requires dramatic remodeling of the cytoskeleton. The regulation of cancer cell migration is determined not only by biochemical factors in the microenvironment but also by the biomechanical contextual information provided by the extracellular matrix (ECM). The responses of the cytoskeleton to chemical signals are well characterized and understood. However, the mechanisms of response to mechanical signals in the form of externally applied force and forces generated by the ECM are still poorly understood. Furthermore, understanding the way cellular mechanosensors interact with the physical properties of the microenvironment and transmit the signals to activate the cytoskeletal movements may help identify an effective strategy for the treatment of cancer. Here, we will discuss the role of tumor microenvironment during cancer metastasis and how physical forces remodel the cytoskeleton through mechanosensing and transduction.

TGF-β-Induced Endothelial to Mesenchymal Transition in Disease and Tissue Engineering

Endothelial to mesenchymal transition (EndMT) is a complex biological process that gives rise to cells with multipotent potential. EndMT is essential for the formation of the cardiovascular system during embryonic development. Emerging results link EndMT to the postnatal onset and progression of fibrotic diseases and cancer. Moreover, recent reports have emphasized the potential for EndMT in tissue engineering and regenerative applications by regulating the differentiation status of cells. Transforming growth factor β (TGF-β) engages in many important physiological processes and is a potent inducer of EndMT. In this review, we first summarize the mechanisms of the TGF-β signaling pathway as it relates to EndMT. Thereafter, we discuss the pivotal role of TGF-β-induced EndMT in the development of cardiovascular diseases, fibrosis, and cancer, as well as the potential application of TGF-β-induced EndMT in tissue engineering.

Endothelial Cells in the Tumor Microenvironment

Angiogenesis is a critical process required for tumor progression. Newly formed blood vessels provide nutrition and oxygen to the tumor contributing to its growth and development. However, endothelium also plays other functions that promote tumor metastasis. It is involved in intravasation, which allows invasive cancer cells to translocate into the blood vessel lumen. This phenomenon is an important stage for cancer metastasis. Besides direct association with cancer development, endothelial cells are one of the main sources of cancer-associated fibroblasts (CAFs). The heterogeneous group of CAFs is the main inductor of migration and invasion abilities of cancer cells. Therefore, the endothelium is also indirectly responsible for metastasis. Considering the above, the endothelium is one of the important targets of anticancer therapy. In the chapter, we will present mechanisms regulating endothelial function, dependent on cancer and cancer niche cells. We will focus on possibilities of suppressing pro-metastatic endothelial functions, applied in anti-cancer therapies.

The Benzimidazole-Based Anthelmintic Parbendazole: A Repurposed Drug Candidate That Synergizes with Gemcitabine in Pancreatic Cancer

Pancreatic cancer (PC) is one of the most lethal, chemoresistant malignancies and it is of paramount importance to find more effective therapeutic agents. Repurposing of non-anticancer drugs may expand the repertoire of effective molecules. Studies on repurposing of benzimidazole-based anthelmintics in PC and on their interaction with agents approved for PC therapy are lacking. We analyzed the effects of four Food and Drug Administration (FDA)-approved benzimidazoles on AsPC-1 and Capan-2 pancreatic cancer cell line viability. Notably, parbendazole was the most potent benzimidazole affecting PC cell viability, with half maximal inhibitory concentration (IC₅₀) values in the nanomolar range. The drug markedly inhibited proliferation, clonogenicity and migration of PC cell lines through mechanisms involving alteration of microtubule organization and formation of irregular mitotic spindles. Moreover, parbendazole interfered with cell cycle progression promoting G2/M arrest, followed by the emergence of enlarged, polyploid cells. These abnormalities, suggesting a mitotic catastrophe, culminated in PC cell apoptosis, are also associated with DNA damage in PC cell lines. Remarkably, combinations of parbendazole with gemcitabine, a drug employed as first-line treatment in PC, synergistically decreased PC cell viability. In conclusion, this is the first study providing evidence that parbendazole as a single agent, or in combination with gemcitabine, is a repurposing candidate in the currently dismal PC therapy.

Endothelial-to-Mesenchymal Transition (EndoMT): Roles in Tumorigenesis, Metastatic Extravasation and Therapy Resistance

Cancer cells evolve in a very complex tumor microenvironment, composed of several cell types, among which the endothelial cells are the major actors of the tumor angiogenesis. Today, these cells are also characterized for their plasticity, as endothelial cells have demonstrated their potential to modify their phenotype to differentiate into mesenchymal cells through the endothelial-to-mesenchymal transition (EndoMT). This cellular plasticity is mediated by various stimuli including transforming growth factor-β (TGF-β) and is modulated dependently of experimental conditions. Recently, emerging evidences have shown that EndoMT is involved in the development and dissemination of cancer and also in cancer cell to escape from therapeutic treatment. In this review, we summarize current updates on EndoMT and its main induction pathways. In addition, we discuss the role of EndoMT in tumorigenesis, metastasis, and its potential implication in cancer therapy resistance.

TUBB4B Downregulation Is Critical for Increasing Migration of Metastatic Colon Cancer Cells

Tumor metastasis, the major problem for clinical oncology in colon cancer treatment, is linked with an epithelial-mesenchymal transition (EMT). The observed cellular transformation in this process is manifested by cell elongation, enhanced cell migration and invasion ability, coordinated by cytoskeleton reorganization. In the present study, we examined the role of tubulin-β4 (TUBB4B) downregulation that occurs during EMT in colon cancer cells, in the modulation of the function of microtubules. Based on biochemical and behavioral analysis (transmigration) we posit that the decrease of the TUBB4B level is critical for microtubule-vimentin interaction and contributes to the maintenance of polarity in migrating cells. The microscopic studies revealed that TUBB4B decrease is accompanied by cell elongation and increased number of matured focal adhesion sites, which is a characteristic of the cell metastatic stage. We also demonstrated faster polymerization of microtubules in cells with a lower level of TUBB4B. Simultaneous TUBB3 upregulation, reported during EMT, acts additively in this process. Our studies suggest that the protein level of TUBB4B could be used as a marker for detection of the preinvasive stages of the colon cancer cells. We also concluded that chemotherapy enriched to increase TUBB4B level and/or to stabilize microtubule polymerization might more effectively prevent metastasis in colon cancer development.

Trichostatin a inhibits phenotypic transition and induces apoptosis of the TAF-treated normal colonic epithelial cells through regulation of TGF-β pathway

Tumor-associated fibroblasts (TAFs) contribute to transdifferentiation of stromal cells in tumor microenvironment. Epithelial-mesenchymal transition (EMT) is a procedure of phenotypic remodeling of epithelial cells and extensively exists in local tumoral stroma. Histone deacetylase (HDAC) inhibitor Tricostatin A (TSA) and sodium butyrate (SB) are reported to play important roles in the regulation of biological behaviour of cancer cells. However, whether TSA or SB is involved in control of EMT in colon epithelial cells induced by TAFs remains unidentified. In present study, we used conditioned medium (CM) form TAF-like CCD-18Co cells to stimulate 2D- and 3D-cultured colon epithelial HCoEpiC cells for 24 h and 4 d. We found that the CCD-18Co CM triggered multiple morphological changes in HCoEpiCs including prolonged cell diameters, down-regulation of E-cadherin and up-regulation of vimentin and α-SMA. Besides, ZEB1 and Snail expression and migration were also promoted by the CM. These phenomena were abolised by 5 μg/ml LY364947, a TGF-β receptor inhibitor. CCD-18Co induced up-regulation of HDAC1 and HDAC2 in the 2D and 3D models, while no change of HDAC4 exprerssion was found. Treatment of 2 μg/ml TSA reversed the CCD-18Co-induced morphological changes and migration of the HCoEpiCs, and suppressed the downregulation of E-cadherin and upregulation of vimentin, α-SMA, ZEB1 and Snail. However, the suppressive effect of 4 mg/ml SB on the EMT was not observed. TSA down-regulated the expressions of Smad2/3, p-Smad2/3 amd HDAC4. Besides, TSA promoted the apoptosis rate (36.84 ± 6.52%) comparing with the CCD-18Co-treated HCoEpiCs (3.52 ± 0.85%, P < 0.05), with promotion of Bax (0.5893±0.0498 in 2D and 0.8867±0.0916 in 3D) and reduction of Bcl-2 (0.0476±0.0053 in 2D and 0.0294±0.0075 in 3D). TSA stimulated expression of phosphorylated-p38 MAPK in 2D (0.3472±0.0249) and 3D (0.3188±0.0248). After pre-treatment with p38 MAPK inhibitor VX-702 (0.5 mg/ml), the apoptosis rate of TSA was decreased in 2D (10.32%) and 3D (5.26%). Our observations demonstrate that epigenetic treatment with HDAC inhibitor TSA may be a useful therapeutic tool for the reversion of TAF-induced EMT in colon epithelium through mediating canonical Smads pathway and non-canonical p38 MAPK signalling.

Role of Cancer-Associated Fibroblast in Gastric Cancer Progression and Resistance to Treatments

Although the survival of gastric cancer (GC) patients has gradually improved, the outcomes of advanced GC patients remain unsatisfactory despite standard treatment with conventional chemotherapy or targeted agents. Several studies have shown that cancer-associated fibroblasts (CAFs), a major component of tumor stroma in GC, may have significant roles in GC progression and resistance to treatments. CAFs are a major source of various secreted molecules in the tumor microenvironment, which stimulate cancer cells and other noncancerous components of GC. Surprisingly, these factors could be involved in gastric carcinogenesis. Cytokines, including interleukin-6 and interleukin-11, or growth factors, such as fibroblast growth factor produced from CAFs, can directly activate GC cells and consequently lead to the development of an aggressive phenotype. Galectin-1 or hepatocyte growth factor can be involved in CAF-derived neovascularization in GC. In addition, recent studies showed that CAFs can affect tumor immunity through M2 polarization of tumor-associated macrophages. Finally, the current study aimed to introduce several inhibitory agents and evaluate their suppressive effects on CAFs in patients with GC progression. However, further studies are required to evaluate their safety and select appropriate patients for application in clinical settings.

Nonsteroidal Anti-Inflammatory Drugs Prevent Vincristine-Dependent Cancer-Associated Fibroblasts Formation

Vincristine is used in the clinical treatment of colon cancer, especially in patients diagnosed in the advanced phase of cancer development. Unfortunately, similar to other agents used during antitumor therapy, vincristine might induce chemoresistance. Studies of this process focus mainly on the analysis of the molecular mechanisms within cancer, usually ignoring the role of stromal cells. Our present findings confirm that vincristine stimulates the secretion of tumor growth factors class beta and interleukin-6 from cancer-associated fibroblasts as a result of paracrine stimulation by cancer cells. Based on alterations in morphology, modulation of capillary formation, and changes in endothelial and mesenchymal marker profile, our findings demonstrate that higher levels of tumor growth factor-βs and interleukin-6 enhance cancer-associated fibroblast-like cell formation through endothelial–mesenchymal transition and that nonsteroidal anti-inflammatory drug treatment (aspirin and ibuprofen) is able to inhibit this phenomenon. The process appears to be regulated by the rate of microtubule polymerization, depending on β-tubulin composition. While higher levels of tubulin-β2 and tubulin-β4 caused slowed polymerization and reduced the level of factors secreted to the extracellular matrix, tubulin-β3 induced the opposite effect. We conclude that nonsteroidal anti-inflammatory drugs should be considered for use during vincristine monotherapy in the treatment of patients diagnosed with colorectal cancer.