TIMP-1 via TWIST1 induces EMT phenotypes in human breast epithelial cells

Identification of genes contributing to attenuation of rat model of galactose-induced cataract by pyruvate

Cataracts are a disease that reduces vision due to opacity formation of the lens. Diabetic cataracts occur at young age and progress relatively quickly, so the development of effective treatment has been awaited. Several studies have shown that pyruvate inhibits oxidative stress and glycation of lens proteins, which contribute to onset of diabetic cataracts. However, detailed molecular mechanisms have not been revealed. In this study, we attempted to reduce galactose-induced opacity by pyruvate with rat ex vivo model. Rat lenses were extracted and cultured in galactose-containing medium to induce lens opacity. After opacity had developed, continued culturing with pyruvate in the medium resulted in a reduction of lens opacity. Subsequently, we conducted microarray analysis to investigate the genes that contribute to the therapeutic effect. We performed quantitative expression measurements using RT-qPCR for extracted genes that were upregulated in cataract-induced lenses and downregulated in pyruvate-treated lenses, resulting in the identification of 34 candidate genes. Functional analysis using the STRING database suggests that metallothionein-related factors (Mt1a, Mt1m, and Mt2A) and epithelial-mesenchymal transition-related factors (Acta2, Anxa1, Cd81, Mki67, Timp1, and Tyms) contribute to the therapeutic effect of cataracts.

Human hypofunctional NCF1 variants promote pulmonary fibrosis in the bleomycin-induced mouse model and patients with systemic sclerosis via expansion of SPP1+ monocytes-derived macrophages

OBJECTIVE

We assessed the role of a systemic lupus erythematosus causal hypofunctional variant, neutrophil cytosolic factor 1 (NCF1)-p.Arg90His (p.R90H) substitution, in systemic sclerosis (SSc).

METHODS

Association of NCF1-H90 with SSc was performed in case-control cohorts, bleomycin (BLM)-treated Ncf1-R90 C57BL/6 wildtype and Ncf1-H90 knock-in (KI) littermates. Peripheral blood mononuclear cell (PBMC) subsets were analysed by cytometry by time-of-flight.

RESULTS

The NCF1-H90 allele is associated with risk for diffuse cutaneous SSc (dcSSc) in Chinese and European Americans, and lung fibrosis in Chinese patients with SSc (OR=2.09, p=7.96E-10). Low copy number of NCF1 associated with lung fibrosis in European Americans (OR=4.33, p=2.60E-2). BLM-treated KI mice demonstrated increased pulmonary fibrosis, exhibiting activated type I interferon signature, elevated Spp1, Ccl2, Arg1, Timp1 and Il6 expression, enriched macrophage scores in lung tissues. In a longitudinal observation cohort, homozygous H90 patients with SSc at baseline had increased anti-nuclear antibody titres, anti-topoisomerase antibody seropositivity and anti-centromere antibody seronegativity, increased incidence of lung fibrosis and Gender-Age-lung Physiology index, elevated modified Rodnan Skin Score (mRSS) and elevated plasma osteopontin (OPN, SPP1), CCL2, ARG1, TIMP-1 and IL-6. These H90 patients with SSc sustained elevated mRSS during follow-up years with decreased survival. The 0, 1 and 2 copies of H90 carriage in SSc PBMCs exhibited dose-dependent increases in profibrotic CD14+CD68+CD11b+Tim3+monocytes. Elevated OPN, CCL2 and ARG1 in CD68+CD11b+monocyte-derived macrophages from H90 patients were decreased after co-culturing with anti-CCL2 antibody.

CONCLUSION

Low NCF1 activity increases the risk for the development of dcSSc and lung fibrosis via expanding profibrotic SPP1+MoMs in a CCL2-dependent manner, contributing to the severity of lung fibrosis in both BLM-treated mice and patients with SSc.

MMPs as potential molecular targets in epithelial-to-mesenchymal transition driven COPD progression

Chronic obstructive pulmonary disease (COPD) is the third leading cause of mortality globally and the risk of developing lung cancer is six times greater in individuals with COPD who smoke compared to those who do not smoke. Matrix metalloproteinases (MMPs) play a crucial role in the pathophysiology of respiratory diseases by promoting inflammation and tissue degradation. Furthermore, MMPs are involved in key processes like epithelial-to-mesenchymal transition (EMT), metastasis, and invasion in lung cancer. While EMT has traditionally been associated with the progression of lung cancer, recent research highlights its active involvement in individuals with COPD. Current evidence underscores its role in orchestrating airway remodeling, fostering airway fibrosis, and contributing to the potential for malignant transformation in the complex pathophysiology of COPD. The precise regulatory roles of diverse MMPs in steering EMT during COPD progression needs to be elucidated. Additionally, the less-understood aspect involves how these MMPs bi-directionally activate or regulate various EMT-associated signaling cascades during COPD progression. This review article explores recent advancements in understanding MMPs' role in EMT during COPD progression and various pharmacological approaches to target MMPs. It also delves into the limitations of current MMP inhibitors and explores novel, advanced strategies for inhibiting MMPs, potentially offering new avenues for treating respiratory diseases.

Benzophenone-3 alters expression of genes encoding vascularization and epithelial-mesenchymal transition functions during Trp53-null mammary tumorigenesis

Benzophenone-3 (also referred to as oxybenzone) is a putative endocrine disrupting chemical and common ingredient in sunscreens and other personal care products. We previously showed that benzophenone-3 was promotional for epithelial tumorigenesis in mice fed adult high-fat diet, while protective against the incidence of more aggressive spindle cell tumors in the same treatment group. In this study, we show that benzophenone-3 reduces epithelial to mesenchymal transition in the epithelial tumors of these mice. This reduction in epithelial to mesenchymal transition is associated with altered expression of several genes involved in regulation of angiogenesis and epithelial to mesenchymal transition. Among the genes altered in expression, Timp1 is of particular interest because benzophenone-3 suppressed both migration and Timp1 expression in a mammary tumor cell line that displays epithelial to mesenchymal transition characteristics. These alterations in gene expression plausibly stabilize the vasculature of epithelial carcinomas and contribute to benzophenone-3 promotion of epithelial tumors, while at the same time suppress epithelial to mesenchymal transition and suppress incidence of spindle cell tumors.

Glutamate is effective in decreasing opacity formed in galactose-induced cataract model

Although cataract is the leading cause of blindness worldwide, the detailed pathogenesis of cataract remains unclear, and clinically useful drug treatments are still lacking. In this study, we examined the effects of glutamate using an ex vivo model in which rat lens is cultured in a galactose-containing medium to induce opacity formation. After inducing lens opacity formation in galactose medium, glutamate was added, and the opacity decreased when the culture was continued. Next, microarray analysis was performed using samples in which the opacity was reduced by glutamate, and genes whose expression increased with galactose culture and decreased with the addition of glutamate were extracted. Subsequently, STRING analysis was performed on a group of genes that showed variation as a result of quantitative measurement of gene expression by RT-qPCR. The results suggest that apoptosis, oxidative stress, endoplasmic reticulum (ER) stress, cell proliferation, epithelial-mesenchymal transition (EMT), cytoskeleton, and histones are involved in the formation and reduction of opacity. Therefore, glutamate may reduce opacity by inhibiting oxidative stress and its downstream functions, and by regulating the cytoskeleton and cell proliferation.

Irisin: A Possible Marker of Adipose Tissue Dysfunction in Obesity

Adipose tissue (AT) secretes pro- and anti-inflammatory cytokines involved in AT homeostasis, including tumor necrosis factor-α (TNFα) and irisin. The functionality of AT is based on a regulated equilibrium between adipogenesis and extracellular matrix (ECM) remodeling. We investigated the contributions of adipose progenitors (ASCs) and adipocytes (AMCs) to TNFα-induced ECM remodeling and a possible implication of irisin in AT impairment in obesity. ASCs and AMCs were exposed to TNFα treatment and nuclear factor-kappa (NF-kB) pathway was investigated: Tissue Inhibitor of Metalloproteinase (TIMP-1), Twist Family Transcription Factor 1 (TWIST-1), and peroxisome proliferator-activated receptor-γ (PPARγ) expression levels were analyzed. The proteolytic activity of matrix metalloproteinases (MMPs) -2 and -9 was analyzed by zymography, and the irisin protein content was measured by ELISA. In inflamed AMCs, a TIMP-1/TWIST-1 imbalance leads to a drop in PPARγ. Adipogenesis and lipid storage ability impairment come with local tissue remodeling due to MMP-9 overactivation. In vitro and ex vivo measurements confirm positive correlations among inflammation, adipose secreting irisin levels, and circulating irisin levels in patients with visceral obesity. Our findings identify the NF-kB downstream effectors as molecular initiators of AT dysfunction and suggest irisin as a possible AT damage and obesity predictive factor.

Tissue Inhibitor of Metalloproteinases-1 Overexpression Mediates Chemoresistance in Triple-Negative Breast Cancer Cells

Triple-negative breast cancer (TNBC) is among the most aggressive breast cancer subtypes. Despite being initially responsive to chemotherapy, patients develop drug-resistant and metastatic tumors. Tissue inhibitor of metalloproteinases-1 (TIMP-1) is a secreted protein with a tumor suppressor function due to its anti-proteolytic activity. Nevertheless, evidence indicates that TIMP-1 binds to the CD63 receptor and activates noncanonical oncogenic signaling in several cancers, but its role in mediating TNBC chemoresistance is still largely unexplored. Here, we show that mesenchymal-like TNBC cells express TIMP-1, whose levels are further increased in cells generated to be resistant to cisplatin (Cis-Pt-R) and doxorubicin (Dox-R). Moreover, public dataset analyses indicate that high TIMP-1 levels are associated with a worse prognosis in TNBC subjected to chemotherapy. Knock-down of TIMP-1 in both Cis-Pt-R and Dox-R cells reverses their resistance by inhibiting AKT activation. Consistently, TNBC cells exposed to recombinant TIMP-1 or TIMP-1-enriched media from chemoresistant cells, acquire resistance to both cisplatin and doxorubicin. Importantly, released TIMP-1 reassociates with plasma membrane by binding to CD63 and, in the absence of CD63 expression, TIMP-1-mediated chemoresistance is blocked. Thus, our results identify TIMP-1 as a new biomarker of TNBC chemoresistance and lay the groundwork for evaluating whether blockade of TIMP-1 signal is a viable treatment strategy.

A straightforward method to quantify circulating mRNAs as biomarkers of colorectal cancer

Optimizing the biomarker combination to be analyzed in liquid biopsies should improve personalized medicine. We developed a method to purify circulating cell-free mRNAs from plasma samples and to quantify them by RT-qPCR. We selected three candidate colorectal cancer biomarkers (B2M, TIMP-1, and CLU). Their mRNA levels were significantly higher in plasma of patients with metastatic colorectal cancer patients (mCRC) (n = 107) than in healthy individuals (HI) (n = 53). To increase the discriminating performance of our method, we analyzed the sum of the three mRNA levels (BTC index). The area under the ROC curve (AUC) to estimate the BTC index capacity to discriminate between mCRC and HI plasma was 0.903. We also determined the optimal BTC index cut-off to distinguish between plasma samples, with 82% of sensitivity and 93% of specificity. By using mRNA as a novel liquid biopsy analytical parameter, our method has the potential to facilitate rapid screening of CRCm.

FAM83B promotes the invasion of primary lung adenocarcinoma via PI3K/AKT/NF-κB pathway

OBJECTS

The family with sequence similarity 83B (FAM83B) is one of the markers for poor prognosis in several carcinomas, but the expression and the mechanism resulted in malignant phenotype in lung adenocarcinoma (LUAD) remain to be elucidated.

METHODS

 Data of RNA-seq in LUAD were downloaded from the cancer genome atlas (TCGA) database for differential expression and survival analysis, and immunohistochemistry was employed to analyze the protein expression of FAM83B in 126 cases of primary LUAD. The LUAD cell lines were collected for the detection of the effects on migration and invasion. Then, western blot was performed to measure the expression of tissue inhibitor of metalloproteinase (TIMP)-1 and activation of PI3K/AKT/NF-κB pathway.

RESULTS

FAM83B was overexpressed in multiple types of carcinomas; The differential expression analysis revealed that the level of FAM83B was higher in LUAD than that in para-carcinoma; The patients with overexpression of FAM83B were with shorter overall survival (OS), disease specific survival (DSS) and progress free interval (PFI); Enrichment analysis suggested it was related to the focal adhesion of LUAD. Immunohistochemistry analysis demonstrated that higher FAM83B expression was positively related to lymph node metastasis in primary. Scratch assay and Borden chamber assay showed that the overexpression of FAM83B promoted migration and invasion activity in vitro. Furthermore, high level of FAM83B accelerated the tumorigenesis in vivo. Western blot showed that TIMP-1 was upregulated in H1299/FAM83B OE cells accompanying by the activation of PI3K/AKT/NF-κB pathway.

CONCLUSIONS

FAM83B was a marker for poor prognosis of LUAD and it might promote the expression of TIMP-1 by activating PI3K/AKT/NF-κB pathway and then affect the ECM balance, which resulted in the migration and invasion of LUAD.

Proteins Found in the Triple-Negative Breast Cancer Secretome and Their Therapeutic Potential

The cancer secretome comprises factors secreted by tumors, including cytokines, growth factors, proteins from the extracellular matrix (ECM), proteases and protease inhibitors, membrane and extracellular vesicle proteins, peptide hormones, and metabolic proteins. Secreted proteins provide an avenue for communication with other tumor cells and stromal cells, and these in turn promote tumor growth and progression. Breast cancer is the most commonly diagnosed cancer in women in the US and worldwide. Triple-negative breast cancer (TNBC) is characterized by its aggressiveness and its lack of expression of the estrogen receptor (ER), progesterone receptor (PR), and HER2, making it unable to be treated with therapies targeting these protein markers, and leaving patients to rely on standard chemotherapy. In order to develop more effective therapies against TNBC, researchers are searching for targetable molecules specific to TNBC. Proteins in the TNBC secretome are involved in wide-ranging cancer-promoting processes, including tumor growth, angiogenesis, inflammation, the EMT, drug resistance, invasion, and development of the premetastatic niche. In this review, we catalog the currently known proteins in the secretome of TNBC tumors and correlate these secreted molecules with potential therapeutic opportunities to facilitate translational research.

Matrix metalloproteinases as therapeutic targets in breast cancer

Matrix metalloproteinases (MMPs) are the most prominent proteinases involved in tumorigenesis. They were initially recognized to promote tumor progression by remodeling the extracellular matrix through their proteolytic activity. However, accumulating evidence has revealed that some MMPs have protective roles in cancer progression, and the same MMP can exert opposing roles depending on the cell type in which it is expressed or the stage of cancer. Moreover, studies have shown that MMPs are involved in cancer progression through their roles in other biological processes such as cell signaling and immune regulation, independent of their catalytic activity. Despite the prognostic significance of tumoral or stromal expression of MMPs in breast cancer, their roles and molecular mechanisms in breast cancer progression remain unclear. As the failures of early clinical trials with broad-spectrum MMP inhibitors were mainly due to a lack of drug specificity, substantial efforts have been made to develop highly selective MMP inhibitors. Some recently developed MMP inhibitory monoclonal antibodies demonstrated promising anti-tumor effects in preclinical models of breast cancer. Importantly, anti-tumor effects of these antibodies were associated with the modulation of tumor immune microenvironment, suggesting that the use of MMP inhibitors in combination with immunotherapy can improve the efficacy of immunotherapy in HER2-positive or triple-negative breast cancer. In this review, the current understanding of the roles of tumoral or stromal MMPs in breast cancer is summarized, and recent advances in the development of highly selective MMP inhibitors are discussed.

Cardiac Glycoside Oleandrin Suppresses EMT Ability in Endometrial Carcinoma Cells

Endometrial carcinoma is one of the most common types of cancer among women. The progression of cancer occurs via the Epithelial- Mesenchymal Transition (EMT) pathway. Cells lose their epithelial properties and become mobile. For this reason, the EMT process is one of the most important step to be targeted in cancer treatment. Oleandrin is a cardiac glycoside and its use is limited due to its narrow therapeutic index. In this study, we aimed to evaluate effects of lower level Oleandrin doses on EMT process in endometrial carcinoma. Oleandrin was administrated to Ishikawa endometrial adenocarcinoma cells at different doses and times. IC50 dose was determined by XTT proliferation test. Expression analysis of EMT-related genes was then performed by qRT-PCR. Invasion and colony formation abilities of cells were examined microscopically. Finally, the migration analysis of cancer cells was determined by the Wound Healing Assay. The IC50 dose of Oleandrin applied to Ishikawa cells was determined as 75.3 nM at the 48 h. According to qRT-PCR analysis, expression levels of ZEB1, FN1, ITGB1, VIM, SMAD2, SNAI1, SNAI2, SNAI3, and TGFB3 genes significantly decreased, but TIMP2, TIMP3, ITGAV and GSK3B genes significantly increased. In addition, Oleandrin significantly reduced colony formation and invasion of Ishikawa cells. According to the Wound Healing analysis, the migratory abilities of the Oleandrin-treated cells were reduced compared to the control. Low dose Oleandrin suppresses the EMT pathway in Ishikawa cells. It has been shown that Oleandrin significantly suppresses the cell's colony formation, invasion and migration ability both in gene expression analyzes and microscopically.

Flavonoids as regulators of TIMPs expression in cancer: Consequences, opportunities, and challenges

Cancer is one of the leading causes of death in patients worldwide, where invasion and metastasis are directly responsible for this statement. Although cancer therapy has progressed in recent years, current therapeutic approaches are ineffective due to toxicity and chemoresistance. Therefore, it is essential to evaluate other treatment options, and natural products are a promising alternative as they show antitumor properties in different study models. This review describes the regulation of tissue inhibitors of metalloproteinases (TIMPs) expression and the role of flavonoids as molecules with the antitumor activity that targets TIMPs therapeutically. These inhibitors regulate tissue extracellular matrix (ECM) turnover; they inhibit matrix metalloproteinases (MMPs), cell migration, invasion, and angiogenesis and induce apoptosis in tumor cells. Data obtained in cell lines and in vivo models suggest that flavonoids are chemopreventive and cytotoxic against various types of cancer through several mechanisms. Flavonoids also regulate crucial signaling pathways such as focal adhesion kinase (FAK), phosphatidylinositol-3-kinase (PI3K)-Akt, signal transducer and activator of transcription 3 (STAT3), nuclear factor κB (NFκB), and mitogen-activated protein kinase (MAPK) involved in cancer cell migration, invasion, and metastasis. All these data reposition flavonoids as excellent candidates for use in cancer therapy.

Osteoblast Secretome Modulated by Abiraterone Treatment Affects Castration Resistant Prostate Cancer Cell Proliferation

Abiraterone is a selective inhibitor of androgen biosynthesis approved for the treatment of metastatic patients affected by castration-resistant or castration-sensitive prostate cancer. Intriguingly, clinical data revealed that abiraterone also delayed disease progression in bone improving bone-related endpoints. Our group has previously demonstrated in vitro a direct effect of abiraterone on osteoclast and osteoblast function suggesting its ability to modulate bone microenvironment. Here, we performed an extensive proteomic analysis to investigate how abiraterone influences osteoblast cell secretome and, consequently, osteoblast/prostate cancer cells interaction. A panel of 507 soluble molecules were analyzed in osteoblast conditioned media (OCM) obtained from osteoblast treated or not with abiraterone. Subsequently, OCM was added to prostate cancer cells to investigate its potential effect on prostate cancer cell proliferation and androgen receptor (AR) activation status. Out of 507 screened molecules, 39 of them were differentially expressed in OCM from osteoblasts treated with abiraterone (OCM ABI) compared to OCM obtained from untreated OBs (OCM CTRL). Pathway enrichment analysis revealed that abiraterone down-modulated the release of specific osteoblast soluble factors, positively associated with cell proliferation pathways (false discovery rate adjusted p-value = 0.0019). In vitro validation data showed that OCM ABI treatment significantly reduced cancer proliferation in C4-2B cells (p = 0.022), but not in AR- negative PC-3 cells. Moreover, we also found a reduction in AR activation in C4-2B cells (p = 0.017) confirming the “indirect” anti-tumor AR-dependent effect of abiraterone mediated by osteoblasts. This study provides the first evidence of an additional antitumor effect of abiraterone through the modulation of multiple osteoblast proliferative signals.

The Repertoire of Tissue Inhibitors of Metalloproteases: Evolution, Regulation of Extracellular Matrix Proteolysis, Engineering and Therapeutic Challenges

Tissue inhibitors of metalloproteases (TIMPs) belong to a fascinating protein family expressed in all Metazoa. They act as regulators of the turnover of the extracellular matrix, and they are consistently involved in essential processes. Herein, we recapitulate the main activities of mammalian TIMPs (TIMP1-4) in the control of extracellular-matrix degradation and pathologies associated with aberrant proteostasis. We delineate the activity of TIMPs in the control of extracellular matrix (ECM) homeostasis and discuss the diversity of TIMPs across metazoans taking into account the emergence of the components of the ECM during evolution. Thus, the TIMP repertoire herein analysed includes the homologues from cnidarians, which are coeval with the origins of ECM components; protostomes (molluscs, arthropods and nematodes); and deuterostomes (echinoderms and vertebrates). Several questions, including the maintenance of the structure despite low sequence similarity and the strategies for TIMP engineering, shed light on the possibility to use recombinant TIMPs integrating unique features and binding selectivity for therapeutic applications in the treatment of inflammatory pathologies.

Cooperative interaction between ERα and the EMT-inducer ZEB1 reprograms breast cancer cells for bone metastasis

The epithelial to mesenchymal transition (EMT) has been proposed to contribute to the metastatic spread of breast cancer cells. EMT-promoting transcription factors determine a continuum of different EMT states. In contrast, estrogen receptor α (ERα) helps to maintain the epithelial phenotype of breast cancer cells and its expression is crucial for effective endocrine therapies. Determining whether and how EMT-associated transcription factors such as ZEB1 modulate ERα signaling during early stages of EMT could promote the discovery of therapeutic approaches to suppress metastasis. Here we show that, shortly after induction of EMT and while cells are still epithelial, ZEB1 modulates ERα-mediated transcription induced by estrogen or cAMP signaling in breast cancer cells. Based on these findings and our ex vivo and xenograft results, we suggest that the functional interaction between ZEB1 and ERα may alter the tissue tropism of metastatic breast cancer cells towards bone.

The epithelial mesenchymal transition (EMT) is important in the metastatic spread of cancer cells. Here, the authors show that the EMT transcription factor, ZEB1, can modify estrogen receptor α during EMT and facilitate the migration of breast cancer cells to the bone

Regulation of Tumor Metabolism and Extracellular Acidosis by the TIMP-10-CD63 Axis in Breast Carcinoma

A hallmark of malignant solid tumor is extracellular acidification coupled with metabolic switch to aerobic glycolysis. Using the human MCF10A progression model of breast cancer, we show that glycolytic switch and extracellular acidosis in aggressive cancer cells correlate with increased expression of tissue inhibitor of metalloproteinase-1 (TIMP-1), known to induce intracellular signal transduction through the interaction with its cell surface receptor CD63, independent of its metalloproteinase inhibitory function. We found that, in aggressive breast carcinoma, the TIMP-1–CD63 signaling axis induced a metabolic switch by upregulating the rate of aerobic glycolysis, lowering mitochondrial respiration, preventing intracellular acidification, and inducing extracellular acidosis. Carbonic anhydrase IX (CAIX), a regulator of cellular pH through the hydration of metabolically released pericellular CO₂, was identified as a downstream mediator of the TIMP-1–CD63 signaling axis responsible for extracellular acidosis. Consistently with our previous study, the TIMP-1–CD63 signaling promoted survival of breast cancer cells. Interestingly, breast carcinoma cell survival was drastically reduced upon shRNA-mediated knockdown of CAIX expression, demonstrating the significance of CAIX-regulated pH in the TIMP-1–CD63-mediated cancer cell survival. Taken together, the present study demonstrates the functional significance of TIMP-1–CD63–CAXI signaling axis in the regulation of tumor metabolism, extracellular acidosis, and survival of breast carcinoma. We propose that this axis may serve as a novel therapeutic target.

Single-cell RNA sequencing reveals cell heterogeneity and transcriptome profile of breast cancer lymph node metastasis

Molecular mechanisms underlying breast cancer lymph node metastasis remain unclear. Using single-cell sequencing, we investigated the transcriptome profile of 96,796 single cells from 15 paired samples of primary tumors and axillary lymph nodes. We identified nine cancer cell subclusters including CD44 + / ALDH2 + /ALDH6A1 + breast cancer stem cells (BCSCs), which had a copy-number variants profile similar to that of normal breast tissue. Importantly, BCSCs existed only in primary tumors and evolved into metastatic clusters infiltrating into lymph nodes. Furthermore, transcriptome data suggested that NECTIN2-TIGIT-mediated interactions between metastatic breast cancer cells and tumor microenvironment (TME) cells, which promoted immune escape and lymph node metastasis. This study is the first to delineate the transcriptome profile of breast cancer lymph node metastasis using single-cell RNA sequencing. Our findings offer novel insights into the mechanisms underlying breast cancer metastasis and have implications in developing novel therapies to inhibit the initiation of breast cancer metastasis.

Pooled CRISPR screening in pancreatic cancer cells implicates co-repressor complexes as a cause of multiple drug resistance via regulation of epithelial-to-mesenchymal transition

Background

Pancreatic ductal adenocarcinoma (PDAC) patients suffer poor outcomes, including a five-year survival of below 10%. Poor outcomes result in part from therapeutic resistance that limits the impact of cytotoxic first-line therapy. Novel therapeutic approaches are needed, but currently no targeted therapies exist to treat PDAC.

Methods

To assess cellular resistance mechanisms common to four cytotoxic chemotherapies (gemcitabine, 5-fluorouracil, irinotecan, and oxaliplatin) used to treat PDAC patients, we performed four genome-wide CRISPR activation (CRISPR_act) and CRISPR knock-out (CRISPR_ko) screens in two common PDAC cell lines (Panc-1 and BxPC3). We used pathway analysis to identify gene sets enriched among our hits and conducted RNA-sequencing and chromatin immunoprecipitation-sequencing (ChIP-seq) to characterize top hits from our screen. We used scratch assays to assess changes in cellular migration with HDAC1 overexpression.

Results

Our data revealed activation of ABCG2, a well-described efflux pump, as the most consistent mediator of resistance in each of our screens. CRISPR-mediated activation of genes involved in transcriptional co-repressor complexes also conferred resistance to multiple drugs. Expression of many of these genes, including HDAC1, is associated with reduced survival in PDAC patients. Up-regulation of HDAC1 in vitro increased promoter occupancy and expression of several genes involved in the epithelial-to-mesenchymal transition (EMT). These cells also displayed phenotypic changes in cellular migration consistent with activation of the EMT pathway. The expression changes resulting from HDAC1 activation were also observed with activation of several other co-repressor complex members. Finally, we developed a publicly available analysis tool, PancDS, which integrates gene expression profiles with our screen results to predict drug sensitivity in resected PDAC tumors and cell lines.

Conclusion

Our results provide a comprehensive resource for identifying cellular mechanisms of drug resistance in PDAC, mechanistically implicate HDAC1, and co-repressor complex members broadly, in multi-drug resistance, and provide an analytical tool for predicting treatment response in PDAC tumors and cell lines.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08388-1.

Hyaluronan synthase 2 (HAS2) regulates cell phenotype and invadopodia formation in luminal-like breast cancer cells

Although luminal breast cancer cells are typically highly cohesive epithelial cells and have low invasive ability, many eventually develop metastasis. Until now, the underlying mechanisms remain obscure. In this work, we showed that the level of hyaluronic acid synthase 2 (HAS2) was positively correlated with the malignant phenotype of breast cancer cells. Notably, the increased expression of HAS2 promoted the invasive and migratory abilities of luminal breast cancer cells in vitro, followed by a reduced expression of E-cadherin, β-catenin, and ZO-1, and an elevated expression of N-cadherin and vimentin. Furthermore, overexpression of HAS2 promoted while knockdown of HAS2 impeded invadopodia formation, which subsequently increased or decreased the activation of cortactin, Tks5, and metalloproteinases (MMPs). Activation of these invadopodia-related proteins was prevented by inhibition of HAS2 or disruption of HA, which in turn attenuated the increased motility and invasiveness. Further, in vivo study showed that, HAS2 increased tumor growth and the rate of lung metastasis via driving transition to an invasive cell phenotype in SCID mice that were orthotopically transplanted with luminal breast cancer cells. Collectively, our results showed that HAS2 promoted cell invasion by inducing transition to an invasive phenotype and by enhancing invadopodia formation in luminal breast cancer cells, which may provide new mechanistic insights into its role in tumor metastasis.

The Effect of EZH2 Inhibition through DZNep on Epithelial-Mesenchymal Transition Mechanism

Although the molecular pathogenesis of hepatocellular carcinoma (HCC) is uncertain, it is known that the epithelial-mesenchymal transition (EMT) mechanism and epigenetic changes have an important role. This study was focused on evaluating the relationship of 3-Deazaneplanocin A (DZNep) with the EMT mechanism, which is a histone methyltransferase inhibitor on HCC and is also known as an enhancer of zeste homolog 2 (EZH2) inhibitor. Cell viability of HepG2 cells (HCC cell line) assessed for DZNep over 72 hours with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Additionally, colony-forming assay, apoptosis assay, RNA isolation, cDNA synthesis, and real-time PCR (RT-PCR) were performed to see the effect of DZNep on HepG2 cells. DZNep reduced cell proliferation for 72 hours, also significantly reduced colony formation in addition it increased the total apoptosis. DZNep on EZH2, E-cadherin, N-cadherin, and Vimentin (Vim) gene expressions was given different results by either decreasing or increasing the expressions. In this study, we observed a positive effect of DZNep on apoptosis and TIMP3 expression level and decreased colony formation. However, it gave complicated results with the level of gene expression E-cadherin and TIMP2, increase the level of Vim and MMP2 expression. Therefore, we think that further studies are necessary to clarify the role of DZNep.

Tissue inhibitor of metalloproteinase-1 (TIMP-1) as a prognostic biomarker in gastrointestinal cancer: a meta-analysis

Background

Tissue inhibitor of metalloproteinase 1 (TIMP-1) has recently been shown to be dependent on or independent of Matrix metalloproteinases (MMPs) in its roles in tumorigenesis and progression. This appreciation has prompted various studies assessing the prognostic value of TIMP-1 in patients with gastrointestinal cancer, however, the conclusions were still inconsistent. The aim of this study was to assess the prognostic value of TIMP-1-immunohistochemistry (IHC) staining and pretreatment serum/plasma TIMP-1 level in gastrointestinal cancer survival as well as the association between TIMP-1 and clinicopathologic features.

Methods

The meta-analysis was registered in the International Prospective Register of Systematic Reviews (PROSPERO; Registration NO. CRD42020185407) and followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. A highly sensitive literature search was performed in electronic databases including PubMed, EMBASE and the Cochrane Library. Heterogeneity analysis was conducted using both chi-square-based Q statistics and the I² test. The pooled hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated to assess the prognostic value of TIMP-1 using the fixed-effects model. Odds ratios (ORs) with 95% CIs were calculated to evaluate the associations between TIMP-1 and clinicopathological characteristics. The meta-analysis was conducted using STATA 12.0 software.

Results

A total of 3,958 patients from twenty-two studies were included in the meta-analysis. Elevated TIMP-1 levels were significantly associated with poor survival in gastrointestinal cancer (TIMP-1-IHC staining: HR = 2.04, 95% CI [1.59–2.61], I² = 35.7%, P_Q = 0.156; pretreatment serum/plasma TIMP-1 levels: HR = 2.02, 95% CI [1.80–2.28], I² = 0%, P_Q = 0.630). Moreover, clinicopathological parameter data analysis showed that elevated TIMP-1 levels were significantly associated with lymph node metastasis (N1/N2/N3 vs N0: OR = 2.92, 95% CI [1.95–4.38]) and higher TNM stages (III/IV vs I/II: OR = 2.73, 95% CI [1.23–6.04]).

Conclusion

Both TIMP-1-positive IHC staining and high serum/plasma TIMP-1 levels are poor prognostic factors for the survival of gastrointestinal cancer. In addition, TIMP-1 overexpression was correlated with more advanced clinicopathological features.

The Roles of Matrix Metalloproteinases and Their Inhibitors in Human Diseases

Matrix metalloproteinases (MMPs) are a family of zinc-dependent extracellular matrix (ECM) remodeling endopeptidases that have the capacity to degrade almost every component of the ECM. The degradation of the ECM is of great importance, since it is related to embryonic development and angiogenesis. It is also involved in cell repair and the remodeling of tissues. When the expression of MMPs is altered, it can generate the abnormal degradation of the ECM. This is the initial cause of the development of chronic degenerative diseases and vascular complications generated by diabetes. In addition, this process has an association with neurodegeneration and cancer progression. Within the ECM, the tissue inhibitors of MMPs (TIMPs) inhibit the proteolytic activity of MMPs. TIMPs are important regulators of ECM turnover, tissue remodeling, and cellular behavior. Therefore, TIMPs (similar to MMPs) modulate angiogenesis, cell proliferation, and apoptosis. An interruption in the balance between MMPs and TIMPs has been implicated in the pathophysiology and progression of several diseases. This review focuses on the participation of both MMPs (e.g., MMP-2 and MMP-9) and TIMPs (e.g., TIMP-1 and TIMP-3) in physiological processes and on how their abnormal regulation is associated with human diseases. The inclusion of current strategies and mechanisms of MMP inhibition in the development of new therapies targeting MMPs was also considered.

TGIF1-Twist1 axis in pancreatic ductal adenocarcinoma

TG-interacting factor 1 (TGIF1) exerts inhibitory effects on transforming growth factor-beta (TGF-β) signaling by suppressing Smad signaling pathway at multiple levels. TGIF1 activity is important for normal embryogenesis and organogenesis, yet its dysregulation can culminate in tumorigenesis. For instance, increased expression of TGIF1 correlates with poor prognosis in triple-negative breast cancer patients, and enforced expression of TGIF1 facilitates Wnt-driven mammary tumorigenesis, suggesting that TGIF1 might function as an oncoprotein. Quite surprisingly, TGIF1 has recently been shown to function as a tumor suppressor in pancreatic ductal adenocarcinoma (PDAC), possibly owing to its ability to antagonize the pro-malignant transcription factor Twist1. In this article, we will briefly elaborate on the biological and clinical significance of the unique tumor-suppressive function of TGIF1 and its functional interaction with Twist1 in the context of PDAC pathogenesis and progression.

In Vitro Homeostasis of Rat Oral Epithelial Cell Cultures Following Withdrawal of Periodontal Pathogens

Inflammation of periodontal tissues is the consequence of interaction between periodontal pathogens and immune system. This is associated with increased expression of inflammatory cytokines, which may exert destructive effect to the periodontal tissues when released over long period. The aim of this study was to chronologically track the homeostasis of oral keratinocytes following removal of periodontal pathogens. This was done by investigating expression of selected inflammatory markers and integrity of epithelial monolayers in vitro. Rat oral keratinocytes were stimulated with heat-killed Fusobacterium nucleatum and Porphyromonas gingivalis over 7-days then bacteria were washed away and epithelial cells re-cultured for 3-days. Expression of IL-1β, IL-6, and IL-8 was measured by ELISA while transcription of tissue inhibitor of metalloproteinase-1 (TIMP-1) and matrix metalloproteinase -8 (MMP-8) was measured by polymerase chain reaction before and after removal of bacteria. Integrity of epithelial sheet was investigated by using transepithelial electrical resistance. Data showed general downregulation of IL-1b, IL-6, and IL-8 associated with restoring transcription of TIMP-1 and MMP-8 to normal level following removal of bacteria from epithelial cultures. However, expression of IL-8 and MMP-8 remained significantly higher than unstimulated epithelial cells despite withdrawal of F. nucleatum and P. gingivalis respectively from oral keratinocytes cultures. In addition, integrity of epithelial barrier function remained compromised even after removal of P. gingivalis. Results suggest that even after three days following removal of periodontal pathogens, oral keratinocytes sustained persistent upregulation of certain inflammatory markers that could compromise integrity of epithelial barrier function.

Total saponins from Lilium lancifolium: a promising alternative to inhibit the growth of gastric carcinoma cells

Bulbus Lilii, as a medicinal and edible plant, has anti-inflammatory, anti-oxidative and immunopotentiating pharmacological activities, which seems to be therapeutic on cancer prevention. The purpose of this study was to investigate the effects of total saponins from Lilium lancifolium (TSLL) on proliferation, apoptosis and migration of human gastric carcinoma cells lines SGC-7901 and HGC-27 and its underlying mechanism. The results showed that TSLL inhibited the proliferation of gastric carcinoma cells by suppressing the level of proliferating cell nuclear antigen (PCNA) and increased p21 level. TSLL induced cells apoptosis by up-regulating expression of pro-apoptotic protein Bax and down-regulating anti-apoptotic protein Bcl-2 expression. Meanwhile, TSLL remarkably inhibited cell migration and invasion, decreased matrix metalloproteinase-2 (MMP-2) expression and increased tissue inhibitor of metalloproteinases-1 (TIMP-1) expression. Notably, TSLL had stronger anti-cancer effect on undifferentiated HGC-27 cells than differentiated SGC-7901 cells. Accordingly, TSLL might be a promising candidate to prevent and suppress the growth of gastric carcinoma cells.

Establishment of Structure-Function Relationship of Tissue Inhibitor of Metalloproteinase-1 for Its Interaction with CD63: Implication for Cancer Therapy

Tissue inhibitor of metalloproteinases-1 (TIMP-1) is a pleiotropic protein, promoting both tumor-suppressive and tumor-promoting activities. While TIMP-1 is primarily known as an endogenous inhibitor of matrix metalloproteinases (MMPs) and thus associated with tumor cell invasion, clinical studies demonstrated increased expression of TIMP-1 and its association with poor prognosis in cancer. Non-MMP-inhibitory and oncogenic functions of TIMP-1 are mediated by induction of intracellular signaling via its cell surface receptor CD63, a tetraspanin. The present study investigates the structure-function relationship of TIMP-1 for its interaction with CD63, which may eventually help design a novel approach for targeting TIMP-1's pro-oncogenic activity without interfering its tumor suppressive MMP-inhibitory function. Importantly, our analysis includes TIMP-1/CD63 interactions at the cell surface of live cells. Here, we demonstrate that the 9 C-terminal amino acid residues of TIMP-1 and the large extracellular loop of CD63 are required for their interaction. Considering that the N-terminal half of TIMP-1 is sufficient for TIMP-1's MMP-inhibitory activity, we propose that those C-terminal amino acid residues are a potentially targetable motif of TIMP-1 oncogenic activity. As a proof of concept, we present the potential for the development of neutralizing antibodies against the C-terminal motif of TIMP-1 for disruption of TIMP-1 interaction with CD63 and the subsequent signal transduction.

The Difference of Expression of 18 Genes in Axillary Invasion and Vascular Invasion Compared to Control Samples in Breast Cancer

Background & Objective:

Recent studies from gene profiling have revealed some genes that are overexpressed in the epithelial-mesenchymal transition (EMT) process and are responsible for its initiation and activation resulting in tumor progression and metastasis. The present study aimed to assess the role of genes involved in the EMT process and the association of these genes with axillary lymph node and vascular invasion in breast cancer (BC) patients.

Methods:

In this case-control study, the tumor samples were initially extracted from 33 BC patients. The samples of 15 BC tissues without vascular and axillary invasion were also prepared from the biobank as a control group. RNAs from both tumor and control samples were extracted and stabilized. For assessing overexpression in tumor tissues of selected 18 genes, the real time technique was employed.

Results:

There was a significant increase in MMP-2 gene fold expression in tumor cells with vascular invasion regardless of axillary involvement compared to the control group (P=0.0008) and also in the comparison of the control group with those with vascular invasion and not axillary lymph node involvement (P=0.003). In addition, gene fold expression of tissue inhibitors of metalloproteinase-1(TIMP-1) was decreased in axillary involving tumor cells compared to control group (P=0.045), and also in comparison with all samples that did not present any axillary lymph node involvements including the control group and the group with isolated vascular invasion (P=0.012).

Conclusion:

Overexpression of MMP-2 and under-expression of TIMP-1 were associated with more invasive behavior in breast tumor cells.

Telbivudine antagonizes TLR4 to inhibit the epithelial-to-mesenchymal transition in human proximal tubular epithelial cells in vitro

The antiviral drug Telbivudine (LdT) has an extrahepatic pharmaceutical effect that improves renal inflammation and tubulointerstitial fibrosis. However, the exact mechanism of action requires further investigation. Toll-like receptor 4 (TLR4) is involved in several physiological processes, including inflammation, fibrosis, innate immunity, and hepatitis B virus-associated glomerulonephritis. The epithelial-to-mesenchymal transition (EMT) is the characteristic pathological change in tubulointerstitial fibrosis. In this study, we used transforming growth factor-β (TGF-β) to stimulate human proximal tubular epithelial (HK-2) cells to investigate the effects of LdT in EMT. In addition, we treated HK-2 cells with a TLR4 agonist, lipopolysaccharide, to determine the effect of LdT on TLR4. The results indicated that LdT inhibited the expression of TLR4 and its downstream proteins. It also decreased the release of inflammatory factors, downregulated the TGF-β/Smad signaling pathway, and reversed the EMT changes seen in HK-2 cells. In conclusion, LdT antagonized TLR4 to inhibit EMT in proximal tubular epithelial cells.

A Novel ACKR2-Dependent Role of Fibroblast-Derived CXCL14 in Epithelial-to-Mesenchymal Transition and Metastasis of Breast Cancer

PURPOSE

Fibroblasts expressing the orphan chemokine CXCL14 have been previously shown to associate with poor breast cancer prognosis and promote cancer growth. This study explores the mechanism underlying the poor survival associations of stromal CXCL14.

EXPERIMENTAL DESIGN

Tumor cell epithelial-to-mesenchymal transition (EMT), invasion, and metastasis were studied in in vitro and in vivo models together with fibroblasts overexpressing CXCL14. An approach for CXCL14 receptor identification included loss-of-function studies followed by molecular and functional endpoints. The clinical relevance was further explored in publicly available gene expression datasets.

RESULTS

CXCL14 fibroblasts stimulated breast cancer EMT, migration, and invasion in breast cancer cells and in a xenograft model. Furthermore, tumor cells primed by CXCL14 fibroblasts displayed enhanced lung colonization after tail-vein injection. By loss-of function experiments, the atypical G-protein-coupled receptor ACKR2 was identified to mediate CXCL14-stimulated responses. Downregulation of ACKR2, or CXCL14-induced NOS1, attenuated the pro-EMT and migratory capacity. CXCL14/ACKR2 expression correlated with EMT and survival in gene expression datasets.

CONCLUSIONS

Collectively, the findings imply an autocrine fibroblast CXCL14/ACKR2 pathway as a clinically relevant stimulator of EMT, tumor cell invasion, and metastasis. The study also identifies ACKR2 as a novel mediator for CXCL14 function and thereby defines a pathway with drug target potential.See related commentary by Zhang et al., p. 3476.

miR-214 is Stretch-Sensitive in Aortic Valve and Inhibits Aortic Valve Calcification

miR-214 has been recently found to be significantly downregulated in calcified human aortic valves (AVs). ER stress, especially the ATF4-mediated pathway, has also been shown to be significantly upregulated in calcific AV disease. Since elevated cyclic stretch is one of the major mechanical stimuli for AV calcification and ATF4 is a validated target of miR-214, we investigated the effect of cyclic stretch on miR-214 expression as well as those of ATF4 and two downstream genes (CHOP and BCL2L1). Porcine aortic valve (PAV) leaflets were cyclically stretched at 15% for 48 h in regular medium and for 1 week in osteogenic medium to simulate the early remodeling and late calcification stages of stretch-induced AV disease, respectively. For both stages, 10% cyclic stretch served as the physiological counterpart. RT-qPCR revealed that miR-214 expression was significantly downregulated during the late calcification stage, whereas the mRNA expression of ATF4 and BCL2L1 was upregulated and downregulated, respectively, during both early remodeling and late calcification stages. When PAV leaflets were statically transfected with miR-214 mimic in osteogenic medium for 2 weeks, calcification was significantly reduced compared to the control mimic case. This implies that miR-214 may have a protective role in stretch-induced calcific AV disease.

Krüppel like factor 6 splice variant 1 (KLF6-SV1) overexpression recruits macrophages to participate in lung cancer metastasis by up-regulating TWIST1

The aim of this study was to investigate the mechanism by which KLF6-SV1 promoted lung cancer metastasis through tumor-associated macrophages (TAMs). Plasmid transfection was used to construct cells that upregulated or silenced gene. Tumor-bearing mouse model was established using A549 cells. SP staining was performed to detect the CD163 and CD68. Six-well plates and Transwell chamber were used for co-culture of lung cancer A549 cells and macrophages. CCK-8 and Transwell assay were applied to detected the cell viability and migration respectively. Protein and mRNA were tested by Western blot and quantitative real-time polymerase chain reaction (qRT-PCR).KLF6-SV1 overexpression promoted the expression levels of TWIST1 and CCL2, and also induce macrophage polarization to M2 and epithelial-mesenchymal transition (EMT). In vitro experiments showed that KLF6-SV1 might regulate the migration of lung cancer cells by regulating the expression of TWIST1 and CCL-2. M2 macrophages did not affect the expression of KLF6-SV1, TWIST1 and CCL-2. The co-culture system could up-regulate the EMT of A549 cells.Overexpression of KLF6-SV1 promoted the expression of TWIST1 and CCL2, and up-regulation of TWIST1 expression might promote the infiltration of M2 macrophages, which promoted the involvement of EMT in the metastasis of lung cancer cells.

Troponin I2 as a Specific Biomarker for Prediction of Peritoneal Metastasis in Gastric Cancer

BACKGROUND

Although peritoneal metastasis is a serious concern in patients with gastric cancer, no acceptable and specific biomarker is available. We aimed to identify a candidate biomarker to predict peritoneal metastasis of gastric cancer.

METHODS

Metastatic pathway-specific transcriptome analysis was conducted by comparison of patient groups with no recurrence and with peritoneal, hepatic, and nodal recurrence. Fifteen cell lines and 262 pairs of surgically resected gastric tissues were subjected to messenger RNA (mRNA) expression analysis. Polymerase chain reaction array analysis was performed to explore coordinately expressed cancer-related genes. To evaluate the in situ protein localization and expression patterns, immunohistochemical staining was performed.

RESULTS

From transcriptome data, troponin I2 (TNNI2) was identified as a candidate molecule specifically overexpressed in gastric cancer prone to peritoneal metastasis. TNNI2 mRNA was expressed at differential levels, independent of differentiated phenotype of cell lines. Epithelial to mesenchymal transition-related genes, tumor inhibitor of metalloproteinase 1 (TIMP1), and vacuolar protein sorting 13 homolog A (VPS13A) were expressed with TNNI2 at correlation coefficient > 0.7. The optimal cutoff of TNNI2 expression was determined as 0.00017. High TNNI2 expression was significantly and specifically associated with peritoneal metastasis and served as an independent risk marker for peritoneal recurrence after curative gastrectomy. Prevalence of peritoneal recurrence increased in parallel with staining intensity of TNNI2.

CONCLUSIONS

TNNI2 expression in gastric tissues may serve as a specific biomarker for prediction of peritoneal metastasis of gastric cancer and contribute to improvement of patient management.

Mesenchymal stem cells in combination with erythropoietin repair hyperoxia-induced alveoli dysplasia injury in neonatal mice via inhibition of TGF-β1 signaling

The aim of the present study is to investigate the protection effects of bone marrow mesenchymal stem cells (MSCs) in combination with EPO against hyperoxia-induced bronchopulmonary dysplasia (BPD) injury in neonatal mice. BPD model was prepared by continuous high oxygen exposure, 1×106 bone marrow MSCs and 5000U/kg recombinant human erythropoietin (EPO) were injected respectively. Results showed that administration of MSCs, EPO especially MSCs+EPO significant attenuated hyperoxia-induced lung damage with a decrease of fibrosis, radical alveolar counts and inhibition of the occurrence of epithelial-mesenchymal transition (EMT). Furthermore, MSCs+EPO co-treatment more significantly suppressed the levels of transforming growth factor-β1(TGF-β1) than MSCs or EPO alone. Collectively, these results suggested that MSCs, EPO in particular MSCs+EPO co-treatment could promote lung repair in hyperoxia-induced alveoli dysplasia injury via inhibition of TGF-β1 signaling pathway to further suppress EMT process and may be a promising therapeutic strategy.

TIMP-1 downregulation modulates miR-125a-5p expression and triggers the apoptotic pathway

Matrix metalloproteinases and their natural inhibitors (TIMPs) are important elements in a wide range of oncology settings. Elevated levels of tissue inhibitor of metalloproteinase-1 (TIMP-1) have often been associated with increased tumorigenesis. This has been demonstrated in a number of clinical and experimental models which include breast, gastric, colorectal and non-small cell lung carcinoma (NSCLC). Our earlier studies have identified increased angiogenic activity and aggressive tumor kinetics in TIMP-1 overexpressing H2009 lung adenocarcinoma cells. TIMP-1 overexpression has also been implicated in antiapoptotic responses, inducing a significant upregulation of Bcl-2. These TIMP-1 functions have been shown to be MMP-independent and provide insight into its pleiotropic activities. The current study examines microRNA (miRNA) interactions with this molecule. We have sought to define the relationship between TIMP-1 and miRNA by knocking down TIMP-1 in high TIMP-1 expressing lung adenocarcinoma cell lines. TIMP-1 knockdown resulted in increased expression of miR-125a-5p with a concomitant increase in apoptosis and attenuation of the tumorigenic features of these cells. We have identified TIMP-1 as a bona fide target of miR-125a-5p, and their interaction resulted in an increase in p53 expression. We further corroborated our in vitro data with patient samples, which exhibited an inverse correlation between TIMP-1 and miR-125a-5p expression. Our study lends support to the notion that elevated TIMP-1 levels, which are frequently associated with poor prognosis, cause aberrant modulation of miRNAs.

Gemcitabine-Induced TIMP1 Attenuates Therapy Response and Promotes Tumor Growth and Liver Metastasis in Pancreatic Cancer

Gemcitabine constitutes one of the backbones for chemotherapy treatment in pancreatic ductal adenocarcinoma (PDAC), but patients often respond poorly to this agent. Molecular markers downstream of gemcitabine treatment in preclinical models may provide an insight into resistance mechanisms. Using cytokine arrays, we identified potential secretory biomarkers of gemcitabine resistance (response) in the transgenic KRasG12D; Trp53R172H; Pdx-1 Cre (KPC) mouse model of PDAC. We verified the oncogenic role of the cytokine tissue inhibitor of matrix metalloproteinases 1 (TIMP1) in primary pancreatic tumors and metastases using both in vitro techniques and animal models. We identified potential pathways affected downstream of TIMP1 using the Illumina Human H12 array. Our findings were validated in both primary and metastatic models of pancreatic cancer. Gemcitabine increased inflammatory cytokines including TIMP1 in the KPC mouse model. TIMP1 was upregulated in patients with pancreatic intraepithelial neoplasias grade 3 and PDAC lesions relative to matched normal pancreatic tissue. In addition, TIMP1 played a role in tumor clonogenic survival and vascular density, while TIMP1 inhibition resensitized tumors to gemcitabine and radiotherapy. We observed a linear relationship between TIMP-1 expression, liver metastatic burden, and infiltration by CD11b+Gr1+ myeloid cells and CD4+CD25+FOXP3+ Tregs, whereas the presence of tumor cells was required for immune cell infiltration. Overall, our results identify TIMP1 upregulation as a resistance mechanism to gemcitabine and provide a rationale for combining chemo/radiotherapy with TIMP1 inhibitors in PDAC. Cancer Res; 77(21); 5952-62. ©2017 AACR.

Astaxanthin inhibits gemcitabine-resistant human pancreatic cancer progression through EMT inhibition and gemcitabine resensitization

Pancreatic cancer rapidly acquires resistance to chemotherapy resulting in its being difficult to treat. Gemcitabine is the current clinical chemotherapy strategy; however, owing to gemcitabine resistance, it is only able to prolong the life of patients with pancreatic cancer for a limited number of months. Understanding the underlying molecular mechanisms of gemcitabine resistance and selecting a suitable combination of agents for the treatment of pancreatic cancer is required. Astaxanthin (ASX) is able to resensitize gemcitabine-resistant human pancreatic cancer cells (GR-HPCCs) to gemcitabine. ASX was identified to upregulate human equilibrative nucleoside transporter 1 (hENT1) and downregulate ribonucleoside diphosphate reductase (RRM) 1 and 2 to enhance gemcitabine-induced cell death in GR-HPCCs treated with gemcitabine, and also downregulates TWIST1 and ZEB1 to inhibit the gemcitabine-induced epithelial-mesenchymal transition (EMT) phenotype in GR-HPCCs and to mediate hENT1, RRM1 and RRM2. Furthermore, ASX acts through the hypoxia-inducible factor 1α/signal transducer and activator of transcription 3 signaling pathway to mediate TWIST1, ZEB1, hENT1, RRM1 and RRM2, regulating the gemcitabine-induced EMT phenotype and gemcitabine-induced cell death. Co-treatment with ASX and gemcitabine in a tumor xenograft model induced by GR-HPCCs supported the in vitro results. The results of the present study provide a novel therapeutic strategy for the treatment of gemcitabine-resistant pancreatic cancer.

Benzo(a)pyrene enhances the EMT-associated migration of lung adenocarcinoma A549 cells by upregulating Twist1

Benzo(a)pyrene (BaP), an important toxic component of cigarette smoke, can cause lung cancer and lead to the progression of lung cancer. In the present study, we investigated the effect of BaP on the migration of lung adenocarcinoma A549 cells. BaP (1 µM) promoted the migration of A549 cells in a time-dependent manner and upregulated the expression of the Twist family BHLH transcription factor 1 (Twist1). BaP also induced upregulation of the mesenchymal markers N-cadherin and vimentin and downregulation of the epithelial marker E-cadherin. When the expression of Twist1 was knocked down in A549 cells that were treated with BaP for 4 weeks (A549BaP-4w), the expression of Twist1 decreased, which inhibited the migration capacity of A549BaP-4w cells, the expression of N-cadherin and vimentin was downregulated and the expression of E-cadherin was upregulated. In addition, morphological observations of A549BaP-4w cells revealed that the epithelial characteristics of A549 cells became mesenchymal characteristics. When the expression of Twist1 was knocked down, the A549BaP-4w cells were transformed back to cells with epithelial characteristics. In conclusion, the results from the present study indicate that BaP enhances the epithelial-mesenchymal transition-associated migration of lung adenocarcinoma A549 cells by upregulating Twist1.

Secreted molecules inducing epithelial-to-mesenchymal transition in cancer development

The epithelial-mesenchymal transition (EMT) is a biologic process that allows a polarized epithelial cell to undergo multiple biochemical changes that enable it to assume a mesenchymal cell phenotype. EMT is involved in embryo development, wound healing, tissue regeneration, organ fibrosis and has also been proposed as the critical mechanism for the acquisition of malignant phenotypes by epithelial cancer cells. These cells have been shown to acquire a mesenchymal phenotype when localized at the invasive front of primary tumours increasing aggressiveness, invasiveness, metastatic potential and resistance to chemotherapy. There is now increasing evidence demonstrating that a crucial role in the development of this process is played by factors secreted by cells of the tumour microenvironment or by the tumour cells themselves. This review summarises the current knowledge of EMT induction in cancer by paracrine or autocrine mechanisms, by exosomes or free proteins and miRNAs.

Timp1 Promotes Cell Survival by Activating the PDK1 Signaling Pathway in Melanoma

High TIMP1 expression is associated with poor prognosis in melanoma, where it can bind to CD63 and β1 integrin, inducing PI3-kinase pathway and cell survival. Phosphatidylinositol (3,4,5)-trisphosphate (PIP3), generated under phosphatidylinositol-3-kinase (PI3K) activation, enables the recruitment and activation of protein kinase B (PKB/AKT) and phosphoinositide-dependent kinase 1 (PDK1) at the membrane, resulting in the phosphorylation of a host of other proteins. Using a melanoma progression model, we evaluated the impact of Timp1 and AKT silencing, as well as PI3K, PDK1, and protein kinase C (PKC) inhibitors on aggressiveness characteristics. Timp1 downregulation resulted in decreased anoikis resistance, clonogenicity, dacarbazine resistance, and in vivo tumor growth and lung colonization. In metastatic cells, pAKT^Thr308 is highly expressed, contributing to anoikis resistance. We showed that PDK1^Ser241 and PKCβII^Ser660 are activated by Timp1 in different stages of melanoma progression, contributing to colony formation and anoikis resistance. Moreover, simultaneous inhibition of Timp1 and AKT in metastatic cells resulted in more effective anoikis inhibition. Our findings demonstrate that Timp1 promotes cell survival with the participation of PDK1 and PKC in melanoma. In addition, Timp1 and AKT act synergistically to confer anoikis resistance in advanced tumor stages. This study brings new insights about the mechanisms by which Timp1 promotes cell survival in melanoma, and points to novel perspectives for therapeutic approaches.

TIMPs: versatile extracellular regulators in cancer

A compelling long-term goal of cancer biology is to understand the crucial players during tumorigenesis in order to develop new interventions. Here, we review how the four non-redundant tissue inhibitors of metalloproteinases (TIMPs) regulate the pericellular proteolysis of a vast range of matrix and cell surface proteins, generating simultaneous effects on tumour architecture and cell signalling. Experimental studies demonstrate the contribution of TIMPs to the majority of cancer hallmarks, and human cancers invariably show TIMP deregulation in the tumour or stroma. Of the four TIMPs, TIMP1 overexpression or TIMP3 silencing is consistently associated with cancer progression or poor patient prognosis. Future efforts will align mouse model systems with changes in TIMPs in patients, will delineate protease-independent TIMP function, will pinpoint therapeutic targets within the TIMP-metalloproteinase-substrate network and will use TIMPs in liquid biopsy samples as biomarkers for cancer prognosis.

Pancreatic Premalignant Lesions Secrete Tissue Inhibitor of Metalloproteinases-1, Which Activates Hepatic Stellate Cells Via CD63 Signaling to Create a Premetastatic Niche in the Liver

BACKGROUND & AIMS

Pancreatic ductal adenocarcinoma (PDAC) metastasizes to liver at early stages, making this disease highly lethal. Tissue inhibitor of metalloproteinases-1 (TIMP1) creates a metastasis-susceptible environment in the liver. We investigated the role of TIMP1 and its receptor CD63 in metastasis of early-stage pancreatic tumors using mice and human cell lines and tissue samples.

METHODS

We obtained liver and plasma samples from patients in Germany with chronic pancreatitis, pancreatic intra-epithelial neoplasia, or PDAC, as well as hepatic stellate cells (HSCs). We performed studies with Ptf1a⁺/Cre;Kras⁺/LSL-G12D;Trp53loxP/loxP (CPK) mice, Pdx-1⁺/Cre;Kras⁺/LSL-G12D;Trp53⁺/LSL-R172H (KPC) mice, and their respective healthy littermates as control, and Cd63^-/- mice with their wild-type littermates. KPC mice were bred with Timp1^-/- mice to produce KPCxTimp1^-/- mice. TIMP1 was overexpressed and CD63 was knocked down in mice using adenoviral vectors AdTIMP1 or AdshCD63, respectively. Hepatic susceptibility to metastases was determined after intravenous inoculation of syngeneic 9801L pancreas carcinoma cells. Pancreata and liver tissues were collected and analyzed by histology, immunohistochemical, immunoblot, enzyme-linked immunosorbent assay, and quantitative polymerase chain reaction analyses. We analyzed the effects of TIMP1 overexpression or knockdown and CD63 knockdown in transduced human primary HSCs and HSC cell lines.

RESULTS

Chronic pancreatitis, pancreatic intra-epithelial neoplasia, and PDAC tissues from patients expressed higher levels of TIMP1 protein than normal pancreas. The premalignant pancreatic lesions that developed in KPC and CPK mice expressed TIMP1 and secreted it into the circulation. In vitro and in vivo, TIMP1 activated human or mouse HSCs, which required interaction between TIMP1 and CD63 and signaling via phosphatidylinositol 3-kinase, but not TIMP1 protease inhibitor activity. This signaling pathway induced expression of endogenous TIMP1. TIMP1 knockdown in HSCs reduced their activation. Cultured TIMP1-activated human and mouse HSCs began to express stromal-derived factor-1, which induced neutrophil migration, a marker of the premetastatic niche. Mice with pancreatic intra-epithelial neoplasia-derived systemic increases in TIMP1 developed more liver metastases after injections of pancreatic cancer cells than mice without increased levels of TIMP1. This increase in formation of liver metastases from injected pancreatic cancer cells was not observed in TIMP1 or CD63 knockout mice.

CONCLUSIONS

Expression of TIMP1 is increased in chronic pancreatitis, pancreatic intra-epithelial neoplasia, and PDAC tissues from patients. TIMP1 signaling via CD63 leads to activation of HSCs, which create an environment in the liver that increases its susceptibility to pancreatic tumor cells. Strategies to block TIMP1 signaling via CD63 might be developed to prevent PDAC metastasis to the liver.

Pancreatic cancer stem cell markers and exosomes - the incentive push

Pancreatic cancer (PaCa) has the highest death rate and incidence is increasing. Poor prognosis is due to late diagnosis and early metastatic spread, which is ascribed to a minor population of so called cancer stem cells (CSC) within the mass of the primary tumor. CSC are defined by biological features, which they share with adult stem cells like longevity, rare cell division, the capacity for self renewal, differentiation, drug resistance and the requirement for a niche. CSC can also be identified by sets of markers, which for pancreatic CSC (Pa-CSC) include CD44v6, c-Met, Tspan8, alpha6beta4, CXCR4, CD133, EpCAM and claudin7. The functional relevance of CSC markers is still disputed. We hypothesize that Pa-CSC markers play a decisive role in tumor progression. This is fostered by the location in glycolipid-enriched membrane domains, which function as signaling platform and support connectivity of the individual Pa-CSC markers. Outside-in signaling supports apoptosis resistance, stem cell gene expression and tumor suppressor gene repression as well as miRNA transcription and silencing. Pa-CSC markers also contribute to motility and invasiveness. By ligand binding host cells are triggered towards creating a milieu supporting Pa-CSC maintenance. Furthermore, CSC markers contribute to the generation, loading and delivery of exosomes, whereby CSC gain the capacity for a cell-cell contact independent crosstalk with the host and neighboring non-CSC. This allows Pa-CSC exosomes (TEX) to reprogram neighboring non-CSC towards epithelial mesenchymal transition and to stimulate host cells towards preparing a niche for metastasizing tumor cells. Finally, TEX communicate with the matrix to support tumor cell motility, invasion and homing. We will discuss the possibility that CSC markers are the initial trigger for these processes and what is the special contribution of CSC-TEX.

Twist may be associated with invasion and metastasis of hypoxic NSCLC cells

Hypoxia promotes tumor invasion and metastasis via multiple mechanisms, including epithelial-mesenchymal transition (EMT). Twist, an EMT regulator, has been disclosed to associate with invasion and metastasis as well as poor prognosis of many malignancies. However, it remains undefined whether Twist is involved in invasion and metastasis of hypoxic non-small cell lung cancer (NSCLC). In this study, protein levels of Twist, hypoxia-inducible factor-1α (HIF-1α), and EMT markers (E-cadherin and vimentin) were examined by immunohistochemistry in 76 lung cancer tissues from NSCLC patients. Expression of Twist and its correlation with HIF-1α, E-cadherin, and vimentin were analyzed. Small interfering RNA (siRNA) against Twist was used to knockdown Twist expression in hypoxic NSCLC cells, A549 and NCI-H460. Cellular invasion and protein levels of Twist, E-cadherin, and vimentin were evaluated by matrigel invasion assay and Western blot, respectively. Our results showed that in clinical samples, there was a significant association between Twist expression and differentiation degree, lymph node metastasis, and TNM stage. Correlation analysis demonstrated that expression of Twist was negatively correlated with E-cadherin expression, but positively associated with HIF-1α and vimentin expression. In cultured NSCLC cells, Twist messenger RNA (mRNA) and protein levels were upregulated under hypoxia, while knockdown of Twist suppressed potentiated invasion and expression of mesenchymal marker vimentin induced by hypoxia. Protein level of increased epithelial marker E-cadherin was shown along with Twist downregulation. These findings suggest that Twist promoting hypoxic invasion and metastasis of NSCLC may be associated with altered expression of EMT markers. Inhibition of Twist may be of therapeutic significance.

Twist induces epithelial-mesenchymal transition and cell motility in breast cancer via ITGB1-FAK/ILK signaling axis and its associated downstream network

Twist, a highly conserved basic Helix-Loop-Helix transcription factor, functions as a major regulator of epithelial-mesenchymal transition (EMT) and tumor metastasis. In different cell models, signaling pathways such as TGF-β, MAPK/ERK, WNT, AKT, JAK/STAT, Notch, and P53 have also been shown to play key roles in the EMT process, yet little is known about the signaling pathways regulated by Twist in tumor cells. Using iTRAQ-labeling combined with 2D LC-MS/MS analysis, we identified 194 proteins with significant changes of expression in MCF10A-Twist cells. These proteins reportedly play roles in EMT, cell junction organization, cell adhesion, and cell migration and invasion. ECM-receptor interaction, MAPK, PI3K/AKT, P53 and WNT signaling were found to be aberrantly activated in MCF10A-Twist cells. Ingenuity Pathways Analysis showed that integrin β1 (ITGB1) acts as a core regulator in linking integrin-linked kinase (ILK), Focal-adhesion kinase (FAK), MAPK/ERK, PI3K/AKT, and WNT signaling. Increased Twist and ITGB1 are associated with breast tumor progression. Twist transcriptionally regulates ITGB1 expression. Over-expression of ITGB1 or Twist in MCF10A led to EMT, activation of FAK/ILK, MAPK/ERK, PI3K/AKT, and WNT signaling. Knockdown of Twist or ITGB1 in BT549 and Hs578T cells decreased activity of FAK, ILK, and their downstream signaling, thus specifically impeding EMT and cell invasion. Knocking down ILK or inhibiting FAK, MAPK/ERK, or PI3K/AKT signaling also suppressed Twist-driven EMT and cell invasion. Thus, the Twist-ITGB1-FAK/ILK pathway and their downstream signaling network dictate the Twist-induced EMT process in human mammary epithelial cells and breast cancer cells.