The tumour-induced systemic environment as a critical regulator of cancer progression and metastasis. Nat Cell Biol. 2014;16:717-727. [PMID: 25082194 DOI: 10.1038/ncb3015]

Molecular Evolution of Metaplasia to Adenocarcinoma in the Esophagus

Esophageal adenocarcinoma (EAC) develops from Barrett's esophagus (BE), a condition where the normal squamous epithelia is replaced by specialized intestinal metaplasia in response to chronic gastroesophageal acid reflux. In a minority of individuals, BE can progress to low- and high-grade dysplasia and eventually to intra-mucosal and then invasive carcinoma. BE provides researchers with a unique model to characterize the process by which a carcinoma arises from its precursor lesion. Molecular studies of BE have demonstrated that it is not simply a metaplastic tissue, but rather it harbors frequent alterations that are also present in dysplastic BE and in EAC. Both BE and EAC are characterized by loss of heterozygosity, aneuploidy, specific genetic mutations, and clonal diversity. Epigenetic abnormalities, primary alterations in DNA methylation, are also frequently seen in BE and EAC. Candidate gene and array-based approaches have demonstrated that numerous tumor suppressor genes exhibit aberrant promoter methylation, and some of these altered genes are associated with the neoplastic progression of BE. It has also been shown that the BE and EAC epigenomes are characterized by hypomethylation of intragenic and non-coding regions Recent studies have also provided new insight into the evolutionary forces underlying the molecular alterations seen in BE and EAC and into the molecular pathogenesis of EAC.

Modulating Bone Marrow Hematopoietic Lineage Potential to Prevent Bone Metastasis in Breast Cancer

The presence of disseminated tumor cells in breast cancer patient bone marrow aspirates predicts decreased recurrence-free survival. Although it is appreciated that physiologic, pathologic, and therapeutic conditions impact hematopoiesis, it remains unclear whether targeting hematopoiesis presents opportunities for limiting bone metastasis. Using preclinical breast cancer models, we discovered that marrow from mice treated with the bisphosphonate zoledronic acid (ZA) are metastasis-suppressive. Specifically, ZA modulated hematopoietic myeloid/osteoclast progenitor cell (M/OCP) lineage potential to activate metastasis-suppressive activity. Granulocyte-colony stimulating factor (G-CSF) promoted ZA resistance by redirecting M/OCP differentiation. We identified M/OCP and bone marrow transcriptional programs associated with metastasis suppression and ZA resistance. Analysis of patient blood samples taken at randomization revealed that women with high-plasma G-CSF experienced significantly worse outcome with adjuvant ZA than those with lower G-CSF levels. Our findings support discovery of therapeutic strategies to direct M/OCP lineage potential and biomarkers that stratify responses in patients at risk of recurrence.Significance: Bone marrow myeloid/osteoclast progenitor cell lineage potential has a profound impact on breast cancer bone metastasis and can be modulated by G-CSF and bone-targeting agents. Cancer Res; 78(18); 5300-14. ©2018 AACR.

The Present and Future of Liquid Biopsies in Non-Small Cell Lung Cancer: Combining Four Biosources for Diagnosis, Prognosis, Prediction, and Disease Monitoring

PURPOSE OF REVIEW

Liquid biopsies have potential as tools for diagnosis, prognosis, and prediction of response to therapy. Herein, we will extensively review four liquid biosources, tumor-educated platelets (TEPs), cell-free DNA (cfDNA), circulating tumor cells (CTCs), and extracellular vesicles (EVs) and we will clarify their optimal application in non-small cell lung cancer (NSCLC) diagnosis and therapy.

RECENT FINDINGS

Liquid biopsies are a minimally invasive alternative to tissue biopsies-especially important in NSCLC patients-since tumor tissue is often unavailable or insufficient for complete genetic analysis. The main advantages of liquid biopsies include the possibility for repeated sampling, the lower cost, and the fact that they can reflect the complete molecular status of the patient better than a single-site biopsy. This is specifically important for lung adenocarcinoma patients since the detection of specific genetic alterations can predict response to targeted therapies. Molecular analysis is currently cardinal for therapy decision-making and disease monitoring in lung cancer patients. Liquid biopsies can make easier our daily clinical practice and if prospectively tested and validated may serve as a means for lung cancer early detection.

The liquid biopsy in the management of colorectal cancer patients: Current applications and future scenarios

The term liquid biopsy refers to the analysis of biomarkers in any body fluid, including blood, urine and cerebrospinal fluid. In cancer, liquid biopsy testing allows the analysis of tumor-derived DNA, RNA, miRNA and proteins that can be either cell-free or contained in circulating tumor cells (CTC), extracellular vesicles (EVs) or platelets. A number of studies suggest that liquid biopsy testing could have a relevant role in the management of colorectal cancer (CRC) patients at different stages of the disease. Analysis of cell-free DNA (cfDNA), CTC and/or miRNA can provide relevant information for the early diagnosis of CRC and the identification of minimal residual disease and, more generally, the evaluation of the risk of recurrence in early CRC patients. In addition, liquid biopsy testing might allow the assessment of prognostic and predictive biomarkers in metastatic CRC patients, and the monitoring of the response to treatment and of the clonal evolution of the disease. While a number of elegant studies have shown the potential of liquid biopsy in CRC, the possibility to use this approach in the daily clinical practice is still limited. The use of non-standardized methods, the small cohorts of patients analyzed, the lack of demonstration of a clear clinical benefit are the main limitations of the studies with liquid biopsy in CRC reported up to now. The potential of this approach and the steps that need still to be taken to translate these preliminary findings in the clinic are discussed in this review.

Characterization and In Vivo Validation of a Three-Dimensional Multi-Cellular Culture Model to Study Heterotypic Interactions in Colorectal Cancer Cell Growth, Invasion and Metastasis

Colorectal cancer (CRC) is the third cause of cancer-related mortality in industrialized countries. Local invasion and metastasis formation are events associated with poor prognosis for which today there are no effective therapeutic options. Invasion and metastasis are strongly modulated by cells of the tumor microenvironment (TME), in particular fibroblasts and endothelial cells. Unraveling interactions between tumor cells and cells of the TME may identify novel mechanisms and therapeutic targets to prevent or treat metastasis. We report here the development and in vivo validation of a 3D tumor spheroid model to study the interactions between CRC cells, fibroblasts and endothelial cells in vitro. Co-cultured fibroblasts promoted SW620 and HCT116 CRC spheroid invasion, and this was prevented by the SRC and FGFR kinase inhibitors Dasatinib and Erdafitinib, respectively. To validate these findings in vivo, we injected SW620 cells alone or together with fibroblasts orthotopically in the caecum of mice. Co-injection with fibroblasts promoted lung metastasis growth, which was fully reversed by treatment with Dasatinib or Erdafitinib. Co-culture of SW620 or HCT116 CRC spheroids with endothelial cells suppressed spheroid growth while it had no effect on cancer cell migration or invasion. Consistent with this in vitro effect, co-injected endothelial cells significantly inhibited primary tumor growth in vivo. From these experiments we conclude that effects on cancer cell invasion and growth induced by co-cultured TME cells and drug treatment in the 3D spheroid model in vitro, are predictive of in vivo effects. The 3D spheroid model may be considered as an attractive model to study the effect of heterotypic cellular interactions and drug activities on cancer cells, as animal testing alternative. This model may be adapted and further developed to include different types of cancer and host cells and to investigate additional functions and drugs.

Prognostic significance of nomograms integrating IL-37 expression, neutrophil level, and MMR status in patients with colorectal cancer

Interleukin (IL)‐37 and neutrophils are considered to be involved in human cancer, but their prognostic significance in colorectal cancer (CRC) has not been elucidated. The aim of this study was to evaluate the prognostic value of IL‐37 expression and neutrophil levels in CRC. We retrospectively analyzed IL‐37 expression, CD66b⁺ neutrophil levels, and mismatch repair (MMR) status in 337 paraffin‐embedded CRC specimens from the training cohort by immunohistochemistry. Their prognostic values were assessed using Kaplan‐Meier curves and multivariate Cox regression models. Moreover, several risk factors were used to form nomograms to evaluate survival, and the performance of the nomograms was assessed with respect to calibration, discrimination, and clinical usefulness. Further validation was performed in an independent cohort of 245 cases. Low IL‐37 expression and high CD66b⁺ neutrophil levels were significantly associated with diminished disease‐free survival (DFS) and overall survival (OS), and patients with MMR‐deficient CRC had better clinical outcomes. Furthermore, multivariate Cox analysis identified IL‐37, CD66b⁺ neutrophils, and MMR status as independent prognostic factors for DFS and OS. Two nomograms integrating the three markers with four clinicopathological risk factors were developed and validated for predicting DFS and OS with good calibration and discrimination (C‐index: training cohort, 0.798 (95% confidence interval:0.764‐0.832) and 0.828 (0.796‐0.860), respectively; validation cohort, 0.739 (0.696‐0.783) and 0.761 (0.715‐0.808), respectively). Decision curve analysis demonstrated that the nomograms were clinically useful. Intratumoral IL‐37, CD66b⁺ neutrophils, and MMR status were independent prognostic factors for CRC patients. Nomograms incorporating these biomarkers and clinicopathological features could be conveniently used to facilitate the individualized prediction of DFS and OS.

Circulating Tumor Microparticles Promote Lung Metastasis by Reprogramming Inflammatory and Mechanical Niches via a Macrophage-Dependent Pathway

Despite the frequency of lung metastasis and its associated mortality, the mechanisms behind metastatic tumor cell survival and colonization in the lungs remain elusive. Here, we show that tumor cell-released microparticles (T-MPs) from the primary tumor site play a critical role in the metastatic process. The T-MPs remodeled the lung parenchyma via a macrophage-dependent pathway to create an altered inflammatory and mechanical response to tumor cell invasion. Mechanistically, we show that circulating T-MPs readily enter the lung parenchyma where they are taken up by local macrophages and induce CCL2 production. CCL2 recruits CD11b⁺Ly6C^high inflammatory monocytes to the lungs where they mature into F4/80⁺CD11b⁺Ly6C^- macrophages that not only produce IL6 but also trigger fibrin deposition. IL6 and the deposited fibrin facilitate the survival and growth of tumor-repopulating cells in the lungs by providing chemical and mechanical signals, respectively, thus setting the stage for lung metastasis. These data illustrate that T-MPs reprogram the lung microenvironment promoting metastasis. Cancer Immunol Res; 6(9); 1046-56. ©2018 AACR.

Immune Landscape of Colorectal Cancer Tumor Microenvironment from Different Primary Tumor Location

To define differences in tumor microenvironment (TME) immune phenotypes between right and left colorectal cancers (CRCs) and explore their therapeutic implications. Gene expression profiling and clinical characteristics of patients with CRC were retrieved from The Cancer Genome Atlas data portal. Immune cell infiltration was estimated based on single-sample gene set enrichment analysis. CRCs tissue microarrays (TMAs) containing 90 consecutive cases of surgical samples were used for validation. Expression of CD8A and VEGFA was confirmed by immunohistochemistry (IHC) analysis with TMAs, and overall survival (OS) was analyzed. Expression profiling data demonstrated that CRC immune microenvironment from right side tumor was characterized as increased infiltration of immune cells with enhanced cytotoxic function, based on higher cytotoxic activity scores (CYT) and interferon-γ signatures. Expression of VEGFA, which could be neutralized by bevacizumab, was associated with decreased levels of activated CD8⁺ T-cells, Th1 cells, and PRF1 expression on the right side, but not on the left side. IHC analysis of TMAs further confirmed an inverse correlation between CD8A and VEGFA expression, and revealed a favorable OS for patients with CD8A^HiVEGFA^Lo disease among right-side CRCs. For the left side, higher CD56^bright natural killer cell infiltration and active 4-1BB/IFN-ɑ signaling, which could providing a favorable condition for cetuximab-mediated antibody-dependent cell-mediated cytotoxicity effect, was present in a cohort with extended OS. In the TME, features of immune phenotype sidedness were identified, providing an implication for differential responses to bevacizumab/cetuximab treatment. In addition, a new avenue for innovative experimental design and combinational immunotherapy to treat CRC patients was suggested.

Spleen mediates a distinct hematopoietic progenitor response supporting tumor-promoting myelopoiesis

Cancer progression is associated with alterations of intra- and extramedullary hematopoiesis to support a systemic tumor-promoting myeloid response. However, the functional specialty, mechanism, and clinical relevance of extramedullary hematopoiesis (EMH) remain unclear. Here, we showed that the heightened splenic myelopoiesis in tumor-bearing hosts was not only characterized by the accumulation of myeloid precursors, but also associated with profound functional alterations of splenic early hematopoietic stem/progenitor cells (HSPCs). With the distinct capability to produce and respond to granulocyte-macrophage CSF (GM-CSF), these splenic HSPCs were "primed" and committed to generating immunosuppressive myeloid cells. Mechanistically, the CCL2/CCR2 axis-dependent recruitment and the subsequent local education by the splenic stroma were critical for eliciting this splenic HSPC response. Selective abrogation of this splenic EMH was sufficient to synergistically enhance the therapeutic efficacy of immune checkpoint blockade. Clinically, patients with different types of solid tumors exhibited increased splenic HSPC levels associated with poor survival. These findings reveal a unique and important role of splenic hematopoiesis in tumor-associated myelopoiesis.

The impact of PI3K inhibitors on breast cancer cell and its tumor microenvironment

The phosphoinositide 3-kinase (PI3K) pathway shows frequent aberrant alterations and pathological activation in breast cancer cells. While PI3K inhibitors have not achieved expectant therapeutic efficacy in clinical trials, and several studies provide promising combination strategies to substantially maximize therapeutic outcomes. Besides its direct impact on regulating cancer cells survival, PI3K inhibitors are also demonstrated to have an immunomodulatory impact based on the tumor microenvironment. Inhibition of the leukocyte-enriched PI3K isoforms may break immune tolerance and restore cytotoxic T cell activity by reprogramming the tumor microenvironment. In addition, PI3K inhibitors have pleiotropic effects on tumor angiogenesis and even induce tumor vascular normalization. In this review, we discuss the mechanism of PI3K inhibitor suppression of breast cancer cells and modulation of the tumor microenvironment in order to provide further thoughts for breast cancer treatment.

Tumor-Educated Platelets as a Noninvasive Biomarker Source for Cancer Detection and Progression Monitoring

Liquid biopsies represent a potential revolution in cancer diagnostics as a noninvasive method for detecting and monitoring diseases, complementary to or even replacing current tissue biopsy approaches. Several blood-based biosources and biomolecules, such as cell-free DNA and RNA, proteins, circulating tumor cells, and extracellular vesicles, have been explored for molecular test development. We recently discovered the potential of tumor-educated blood platelets (TEP) as a noninvasive biomarker trove for RNA biomarker panels. TEPs are involved in the progression and spread of several solid tumors, and spliced TEP RNA surrogate signatures can provide specific information on the presence, location, and molecular characteristics of cancers. So far, TEP samples from patients with different tumor types, including lung, brain, and breast cancers, have been tested, and it has been shown that TEPs from patients with cancer are distinct from those with inflammatory and other noncancerous diseases. It remains to be investigated how platelets are "educated," which mechanisms cause intraplatelet RNA splicing, and whether the relative contribution of specific platelet subpopulations changes in patients with cancer. Ultimately, TEP RNA may complement currently used biosources and biomolecules employed for liquid biopsy diagnosis, potentially enhancing the detection of cancer in an early stage and facilitating noninvasive disease monitoring. Cancer Res; 78(13); 3407-12. ©2018 AACR.

TGF-β signaling promotes tumor vasculature by enhancing the pericyte-endothelium association

Background

The breast cancer microenvironment promotes tumor vascularization through the complex interactions involving tumor-associated fibroblasts (TAFs). Emerging data indicate that TAFs increase production and signaling by TGF-β cytokines, while the role of TGF-β signaling in the regulation of tumor blood vessels is not fully understood. The current study presents evidence that TAFs enhance the organization of tumor blood capillaries, and TGF-β signaling plays an important role in this response.

Methods

Tumor vascularization was studied in xenograft models of breast carcinoma cells, alone and in combination with fibroblasts. TGF-β signaling in breast cancer cells was modulated by expression of kinase-inactive TGFBR1-K232R (dnTGFBR1) or constitutive-active TGFBR1-T204D (caTGFBR1) receptor mutants. The architecture of tumor blood capillaries was assessed by immune-histochemical analysis of endothelium and pericytes. The role of TGF-β-Smad signaling in fibronectin expression was examined using adenoviral transduction of signaling components.

Results

Our studies revealed that TAFs significantly increase the lumen size of blood microvessels. Inactivation of TGF-β signaling in tumor cells by dnTGFBR1 reduced the microvessel density and lumen sizes, decreasing tumor growth. In contrast, caTGFBR1-tumors exhibited greater vessel density and lumen sizes. Tumors with inactive dnTGFBR1 showed lower amounts of TAFs, while caTGFBR1 increased amounts of TAFs compared to the control. Inspection of pericytes and endothelial cells in tumor vasculature revealed that TAFs enhanced vessel coverage by pericytes, vascular cells supporting capillaries. This effect was impaired in dnTGFBR1-tumors, whereas active caTGFBR1 enhanced the association of pericytes with endothelium. Accordingly, dnTGFBR1-tumors exhibited the presence of hemorrhages, a sign of fragile blood vessels. Biochemical analysis showed that TGFBR1-SMAD signaling up-regulates fibronectin, a prominent regulator of endothelium-pericyte interactions.

Conclusions

The current study indicates that tumor-fibroblast crosstalk enhances tumor vascularization by increasing the pericyte-endothelium association via a mechanism involving the TGFβ-fibronectin axis. The tumor-fibroblast model represents a useful system for dissecting the complex interactions governing tumor angiogenesis and developing new approaches to therapeutic targeting tumor vasculature.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4587-z) contains supplementary material, which is available to authorized users.

Expression of ID4 protein in breast cancer cells induces reprogramming of tumour-associated macrophages

Background

As crucial regulators of the immune response against pathogens, macrophages have been extensively shown also to be important players in several diseases, including cancer. Specifically, breast cancer macrophages tightly control the angiogenic switch and progression to malignancy. ID4, a member of the ID (inhibitors of differentiation) family of proteins, is associated with a stem-like phenotype and poor prognosis in basal-like breast cancer. Moreover, ID4 favours angiogenesis by enhancing the expression of pro-angiogenic cytokines interleukin-8, CXCL1 and vascular endothelial growth factor. In the present study, we investigated whether ID4 protein exerts its pro-angiogenic function while also modulating the activity of tumour-associated macrophages in breast cancer.

Methods

We performed IHC analysis of ID4 protein and macrophage marker CD68 in a triple-negative breast cancer series. Next, we used cell migration assays to evaluate the effect of ID4 expression modulation in breast cancer cells on the motility of co-cultured macrophages. The analysis of breast cancer gene expression data repositories allowed us to evaluate the ability of ID4 to predict survival in subsets of tumours showing high or low macrophage infiltration. By culturing macrophages in conditioned media obtained from breast cancer cells in which ID4 expression was modulated by overexpression or depletion, we identified changes in the expression of ID4-dependent angiogenesis-related transcripts and microRNAs (miRNAs, miRs) in macrophages by RT-qPCR.

Results

We determined that ID4 and macrophage marker CD68 protein expression were significantly associated in a series of triple-negative breast tumours. Interestingly, ID4 messenger RNA (mRNA) levels robustly predicted survival, specifically in the subset of tumours showing high macrophage infiltration. In vitro and in vivo migration assays demonstrated that expression of ID4 in breast cancer cells stimulates macrophage motility. At the molecular level, ID4 protein expression in breast cancer cells controls, through paracrine signalling, the activation of an angiogenic programme in macrophages. This programme includes both the increase of angiogenesis-related mRNAs and the decrease of members of the anti-angiogenic miR-15b/107 group. Intriguingly, these miRNAs control the expression of the cytokine granulin, whose enhanced expression in macrophages confers increased angiogenic potential.

Conclusions

These results uncover a key role for ID4 in dictating the behaviour of tumour-associated macrophages in breast cancer.

Electronic supplementary material

The online version of this article (10.1186/s13058-018-0990-2) contains supplementary material, which is available to authorized users.

Significance of PI3K/AKT signaling pathway in metastasis of esophageal squamous cell carcinoma and its potential as a target for anti-metastasis therapy

Metastasis is the most lethal hallmark of esophageal squamous cell carcinoma (ESCC). The aim of the study is to identify key signaling pathways that control metastasis in ESCC. Highly invasive ESCC sublines (designated I3 cells) were established through three rounds of selection of cancer cells invading through matrigel-coated chambers. Gene expression profile of one of the I3 sublines was compared with that of its parental cell line using cDNA microarray analysis. Gene ontology and pathway analyses of the differentially expressed genes (both upregulated and downregulated) indicated that genes associated with cellular movement and the AKT pathway were associated with increased cancer cell invasiveness. Western blot analysis confirmed increased phosphorylated AKT (p-AKT), N-cadherin and decreased E-cadherin expression in the I3 cells. Immunohistochemistry was used to evaluate the clinical significance of p-AKT expression in ESCC, and the results showed higher p-AKT nuclear expression in lymph node metastases when compared with primary carcinoma. Inactivation of the PI3K/AKT pathway with specific inhibitors, or with PTEN overexpression, resulted in reversed cadherin switching and inhibited cancer cell motility. Inhibition of the pathway by treatment with wortmannin markedly suppressed experimental metastasis in nude mice. Our data demonstrated the importance of the PI3K/AKT signaling pathway in ESCC metastasis and support PI3K/AKT as a valid therapeutic target in treatment of metastatic ESCC.

Compensation between CSF1R+ macrophages and Foxp3+ Treg cells drives resistance to tumor immunotherapy

Redundancy and compensation provide robustness to biological systems but may contribute to therapy resistance. Both tumor-associated macrophages (TAMs) and Foxp3+ regulatory T (Treg) cells promote tumor progression by limiting antitumor immunity. Here we show that genetic ablation of CSF1 in colorectal cancer cells reduces the influx of immunosuppressive CSF1R+ TAMs within tumors. This reduction in CSF1-dependent TAMs resulted in increased CD8+ T cell attack on tumors, but its effect on tumor growth was limited by a compensatory increase in Foxp3+ Treg cells. Similarly, disruption of Treg cell activity through their experimental ablation produced moderate effects on tumor growth and was associated with elevated numbers of CSF1R+ TAMs. Importantly, codepletion of CSF1R+ TAMs and Foxp3+ Treg cells resulted in an increased influx of CD8+ T cells, augmentation of their function, and a synergistic reduction in tumor growth. Further, inhibition of Treg cell activity either through systemic pharmacological blockade of PI3Kδ, or its genetic inactivation within Foxp3+ Treg cells, sensitized previously unresponsive solid tumors to CSF1R+ TAM depletion and enhanced the effect of CSF1R blockade. These findings identify CSF1R+ TAMs and PI3Kδ-driven Foxp3+ Treg cells as the dominant compensatory cellular components of the immunosuppressive tumor microenvironment, with implications for the design of combinatorial immunotherapies.

Actin cytoskeleton remodeling drives epithelial-mesenchymal transition for hepatoma invasion and metastasis in mice

High invasiveness is a hallmark of human hepatocellular carcinoma (HCC). Large tumors predict invasion and metastasis. Epithelial-mesenchymal transition (EMT) is crucial for cancer invasion and metastasis. However, the mechanisms whereby large tumors tend to undergo EMT remain unclear. We conducted a subgenome-wide screen and identified KLHL23 as an HCC invasion suppressor by inhibiting EMT. KLHL23 binds to actin and suppresses actin polymerization. KLHL23 silencing induced filopodium and lamellipodium formation. Moreover, EMT was suppressed by KLHL23 through its action on actin dynamics. Traditionally, actin cytoskeleton remodeling is downstream of EMT reprogramming. It is therefore intriguing to ask why and how KLHL23 inversely regulates EMT. Activation of actin cytoskeleton remodeling by either KLHL23 silencing or treatment with actin cytoskeleton modulators augmented cellular hypoxic responses in a cell-density-dependent manner, resulting in hypoxia-inducible factor (HIF) and Notch signals and subsequent EMT. Environmental hypoxia did not induce EMT unless actin cytoskeleton remodeling was simultaneously activated and only when cells were at high density. The resulting EMT was reversed by either adenosine 5'-triphosphate supplementation or actin polymerization inhibitors. Down-regulation of KLHL23 was associated with invasion, metastasis, and poor prognosis of HCC and pancreatic cancer. Correlations of tumor size with EMT and inverse association of expression of KLHL23 with HIF/Notch signals were further validated in patient-derived xenograft HCCs in mice.

CONCLUSION

Simultaneously activation of actin cytoskeleton remodeling by intrinsic (such as KLHL23 down-regulation) or microenvironment cues is crucial for cell-density-dependent and hypoxia-mediated EMT, providing a mechanistic link between large tumor size and invasion/metastasis. Our findings provide a means of developing the prevention and treatment strategies for tumor invasion and metastasis. (Hepatology 2018;67:2226-2243).

Functional interplay between secreted ligands and receptors in melanoma

Melanoma, the most aggressive form of skin cancer, results from the malignant transformation of melanocytes located in the basement membrane separating the epidermal and dermal skin compartments. Cutaneous melanoma is often initiated by solar ultraviolet radiation (UVR)-induced mutations. Melanocytes intimately interact with keratinocytes, which provide growth factors and melanocortin peptides acting as paracrine regulators of proliferation and differentiation. Keratinocyte-derived melanocortins activate melanocortin-1 receptor (MC1R) to protect melanocytes from the carcinogenic effect of UVR. Accordingly, MC1R is a major determinant of susceptibility to melanoma. Despite extensive phenotypic heterogeneity and high mutation loads, the molecular basis of melanomagenesis and the molecules mediating the crosstalk between melanoma and stromal cells are relatively well understood. Mutations of intracellular effectors of receptor tyrosine kinase (RTK) signalling, notably NRAS and BRAF, are major driver events more frequent than mutations in RTKs. Nevertheless, melanomas often display aberrant signalling from RTKs such as KIT, ERRB1-4, FGFR, MET and PDGFR, which contribute to disease progression and resistance to targeted therapies. Progress has also been made to unravel the role of the tumour secretome in preparing the metastatic niche. However, key aspects of the melanoma-stroma interplay, such as the molecular determinants of dormancy, remain poorly understood.

Metastatic cancers promote cachexia through ZIP14 upregulation in skeletal muscle

Patients with metastatic cancer experience a severe loss of skeletal muscle mass and function known as cachexia. Cachexia is associated with poor prognosis and accelerated death in patients with cancer, yet its underlying mechanisms remain poorly understood. Here, we identify the metal-ion transporter ZRT- and IRT-like protein 14 (ZIP14) as a critical mediator of cancer-induced cachexia. ZIP14 is upregulated in cachectic muscles of mice and in patients with metastatic cancer and can be induced by TNF-α and TGF-β cytokines. Strikingly, germline ablation or muscle-specific depletion of Zip14 markedly reduces muscle atrophy in metastatic cancer models. We find that ZIP14-mediated zinc uptake in muscle progenitor cells represses the expression of MyoD and Mef2c and blocks muscle-cell differentiation. Importantly, ZIP14-mediated zinc accumulation in differentiated muscle cells induces myosin heavy chain loss. These results highlight a previously unrecognized role for altered zinc homeostasis in metastatic cancer-induced muscle wasting and implicate ZIP14 as a therapeutic target for its treatment.

Elevated peripheral blood B lymphocytes and CD3+CD4-CD8- T lymphocytes in patients with non-small cell lung cancer: A preliminary study on peripheral immune profile

It has been established that the tumor microenvironment (TME) has a crucial role in enabling tumors to evade from host immune responses. Previous studies demonstrated that tumor cells are not only able to reshape immune milieu at the tumor site, but also exert systemic effects, which has been demonstrated to be important for metastasis. At present, how the peripheral immune environment change in the tumor-bearing host is unclear. The present study identified a number of changes in the proportions of lymphocyte subpopulations and the levels of cytokines in patients with NSCLC, which may provide a preliminary profile of the immune environment in the peripheral blood of patients harboring a tumor. These findings expand on the present knowledge on how tumors can alter the immune system to benefit its growth and metastasis, which may provide a potential novel strategy for immunotherapy.

Genetic Modifiers of the Breast Tumor Microenvironment

Multiple nonmalignant cell types in the tumor microenvironment (TME) impact breast cancer risk, metastasis, and response to therapy, yet most heritable mechanisms that influence TME cell function and breast cancer outcomes are largely unknown. Breast cancer risk is ∼30% heritable and >170 genetic loci have been associated with breast cancer traits. However, the majority of candidate genes have poorly defined mechanistic roles in breast cancer biology. Research indicates that breast cancer risk modifiers directly impact cancer cells, yet it is equally plausible that some modifier alleles impact the nonmalignant TME. The objective of this review is to examine the list of current breast cancer candidate genes that may modify breast cancer risk and outcome through the TME.

A novel zebrafish intestinal tumor model reveals a role for cyp7a1-dependent tumor-liver crosstalk in causing adverse effects on the host

The nature of host organs and genes that underlie tumor-induced physiological disruption on the host remains ill-defined. Here, we establish a novel zebrafish intestinal tumor model that is suitable for addressing this issue, and find that hepatic cyp7a1, the rate-limiting factor for synthesizing bile acids [or, in the case of zebrafish, bile alcohol (BA)], is such a host gene. Inducing kras^G12D by Gal4 specifically expressed in the posterior intestine resulted in the formation of an intestinal tumor. The local intestinal tumor caused systemic detrimental effects on the host, including liver inflammation, hepatomegaly, growth defects and organismal death. Whole-organism-level gene expression analysis and metabolite measurements revealed that the intestinal tumor reduced total BA levels, possibly via altered expression of hepatic cyp7a1 Genetically overexpressing cyp7a1 in the liver restored BA synthesis and ameliorated tumor-induced liver inflammation, but not other tumor-dependent phenotypes. Thus, we found a previously unknown role of cyp7a1 as the host gene that links the intestinal tumor, hepatic cholesterol-BA metabolism and liver inflammation in tumor-bearing zebrafish larvae. Our model provides an important basis to discover host genes responsible for tumor-induced phenotypes and to uncover mechanisms underlying how tumors adversely affect host organisms.

The contributions of cancer cell metabolism to metastasis

Metastasis remains the leading cause of cancer-related deaths worldwide, and our inability to identify the tumour cells that colonize distant sites hampers the development of effective anti-metastatic therapies. However, with recent research advances we are beginning to distinguish metastasis-initiating cells from their non-metastatic counterparts. Importantly, advances in genome sequencing indicate that the acquisition of metastatic competency does not involve the progressive accumulation of driver mutations; moreover, in the early stages of tumorigenesis, cancer cells harbour combinations of driver mutations that endow them with metastatic competency. Novel findings highlight that cells can disseminate to distant sites early during primary tumour growth, remaining dormant and untreatable for long periods before metastasizing. Thus, metastatic cells must require local and systemic influences to generate metastases. This hypothesis suggests that factors derived from our lifestyle, such as our diet, exert a strong influence on tumour progression, and that such factors could be modulated if understood. Here, we summarize the recent findings on how specific metabolic cues modulate the behaviour of metastatic cells and how they influence the genome and epigenome of metastatic cells. We also discuss how crosstalk between metabolism and the epigenome can be harnessed to develop new anti-metastatic therapies.

Status and future directions in the management of pancreatic cancer: potential impact of nanotechnology

Pancreatic ductal adenocarcinoma (PDAC) is typically diagnosed at a late stage, has limited treatments, and patients have poor survival rates. It currently ranks as the seventh leading cause of cancer deaths globally and has increasing rates of diagnosis. Improved PDAC treatment requires the development of innovative, effective, and economical therapeutic drugs. The late stage diagnosis limits options for surgical resection, and traditional PDAC chemotherapeutics correlate with increased organ and hematologic toxicity. In addition, PDAC tumor tissue is dense and highly resistant to many traditional chemotherapeutic applications, making the disease difficult to treat and impeding options for palliative care. New developments in nanotechnology may offer innovative options for targeted PDAC therapeutic drug delivery. Nanotechnology can be implemented using multimodality methods that offer increased opportunities for earlier diagnosis, precision enhanced imaging, targeted long-term tumor surveillance, and controlled drug delivery, as well as improved palliative care and patient comfort. Nanoscale delivery methods have demonstrated the capacity to infiltrate the dense, fibrous tumor tissue associated with PDAC, increasing delivery and effectiveness of chemotherapeutic agents and reducing toxicity through the loading of multiple drug therapies on a single nano delivery vehicle. This review presents an overview of nanoscale drug delivery systems and multimodality carriers at the forefront of new PDAC treatments.

The relationship between 18 F-FDG-PETCT-derived markers of tumour metabolism and systemic inflammation in patients with recurrent disease following surgery for colorectal cancer

AIM

¹⁸ F-fluorodeoxyglucose positron emission tomography-computed tomography (¹⁸ F-FDG-PETCT)-derived markers of tumour metabolism have been reported to have prognostic significance in a variety of tumours. Host inflammation is also recognized to have prognostic significance. The aim of the present study was to investigate the relationship between these markers and host systemic inflammation in patients undergoing elective surgery for colorectal cancer.

METHOD

Patients with histologically confirmed colorectal cancer who underwent elective surgery between 2008 and 2015 and also underwent ¹⁸ F-FDG-PETCT at a single centre were included (n = 103). The neutrophil-lymphocyte ratio (NLR) and modified Glasgow Prognostic Score (mGPS) were derived from routine blood tests. The maximum standardized uptake (SUVmax), peak standardized uptake (SUVpeak), metabolic tumour volume (MTV) and total lesion glycolysis (TLG) were measured.

RESULTS

There was no association between ¹⁸ F-FDG-PETCT measures of tumour metabolism and systemic inflammation in the 33 patients who underwent preoperative imaging. Of the 70 patients with recurrent disease who underwent ¹⁸ F-FDG-PETCT during follow-up, patients with NLR ≥ 5 had a significantly higher SUVmax (20 vs 7, P = 0.002), SUVpeak (14 vs 5, P < 0.001), MTV (29 g vs 2 g, P = 0.001) and TLG (338 g vs 9 g, P < 0.001). Similarly, patients with a mGPS of 1-2 at the time of ¹⁸ F-FDG-PETCT had a significantly higher median SUVmax (11 vs 6, P = 0.048), SUVpeak (8 vs 4, P = 0.046), MTV (13 ml vs 2 ml, P = 0.005) and TLG (146 g vs 10 g, P = 0.004).

CONCLUSION

The present study reports a direct association between ¹⁸ F-FDG-PETCT-derived measures of tumour metabolism and systemic inflammation in patients with recurrent colorectal cancer.

A functional genomic screen in vivo identifies CEACAM5 as a clinically relevant driver of breast cancer metastasis

Tumor cells disseminate early in tumor development making metastasis-prevention strategies difficult. Identifying proteins that promote the outgrowth of disseminated tumor cells may provide opportunities for novel therapeutic strategies. Despite multiple studies demonstrating that the mesenchymal-to-epithelial transition (MET) is critical for metastatic colonization, key regulators that initiate this transition remain unknown. We serially passaged lung metastases from a primary triple negative breast cancer xenograft to the mammary fat pads of recipient mice to enrich for gene expression changes that drive metastasis. An unbiased transcriptomic signature of potential metastatic drivers was generated, and a high throughput gain-of-function screen was performed in vivo to validate candidates. Carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5) was identified as a metastatic driver. CEACAM5 overproduction enriched for an epithelial gene expression pattern and facilitated tumor outgrowth at metastatic sites. Tissues from patients with metastatic breast cancer confirmed elevated levels of CEACAM5 in lung metastases relative to breast tumors, and an inverse correlation between CEACAM5 and the mesenchymal marker vimentin was demonstrated. Thus, CEACAM5 facilitates tumor outgrowth at metastatic sites by promoting MET, warranting its investigation as a therapeutic target and biomarker of aggressiveness in breast cancer.

A screen for drivers of metastasis has revealed a key protein involved in the spread of breast cancer into lung tissues. A US research team led by Helen Piwnica-Worms from the University of Texas MD Anderson Cancer Center in Houston enriched cells for genes involved in metastasis by engrafting mice with breast tumor biopsies taken from women with metastatic triple negative breast cancer and then metastases of these mice to mammary fat pads of recipient mice. The researchers pinpointed the gene encoding CEACAM5—a protein known to play a role in cell invasion and spread—as a key promoter of the cellular transition associated with metastasis. Tissues samples from patients confirmed that CEACAM5 levels were elevated in metastatic lung tumors relative to primary breast tumors. The protein provides a potential therapeutic target for drug development and candidate biomarker for patient stratification.

Alternagin-C binding to α2β1 integrin controls matrix metalloprotease-9 and matrix metalloprotease-2 in breast tumor cells and endothelial cells

Background

Matrix metalloproteinases (MMPs) are key players in tumor progression, helping tumor cells to modify their microenvironment, which allows cell migration to secondary sites. The role of integrins, adhesion receptors that connect cells to the extracellular matrix, in MMP expression and activity has been previously suggested. However, the mechanisms by which integrins control MMP expression are not completely understood. Particularly, the role of α2β1 integrin, one of the major collagen I receptors, in MMP activity and expression has not been studied. Alternagin-C (ALT-C), a glutamate-cysteine-aspartate-disintegrin from Bothrops alternatus venom, has high affinity for an α2β1 integrin. Herein, we used ALT-C as a α2β1 integrin ligand to study the effect of ALT-C on MMP-9 and MMP-2 expression as well as on tumor cells, fibroblats and endothelial cell migration.

Methods

ALT-C was purified by two steps of gel filtration followed by anion exchange chromatography. The α₂β₁ integrin binding properties of ALT-C, its dissociation constant (K_d) relative to this integrin and to collagen I (Col I) were determined by surface plasmon resonance. The effects of ALT-C (10, 40, 100 and 1000 nM) in migration assays were studied using three human cell lines: human fibroblasts, breast tumor cell line MDA-MB-231, and microvascular endothelial cells HMEC-1, considering cells found in the tumor microenvironment. ALT-C effects on MMP-9 and MMP-2 expression and activity were analyzed by quantitative PCR and gelatin zymography, respectively. Focal adhesion kinase activation was determined by western blotting.

Results

Our data demonstrate that ALT-C, after binding to α₂β₁ integrin, acts by two distinct mechanisms against tumor progression, depending on the cell type: in tumor cells, ALT-C decreases MMP-9 and MMP-2 contents and activity, but increases focal adhesion kinase phosphorylation and transmigration; and in endothelial cells, ALT-C inhibits MMP-2, which is necessary for tumor angiogenesis. ALT-C also upregulates c-Myc mRNA level, which is related to tumor suppression.

Conclusion

These results demonstrate that α₂β₁ integrin controls MMP expression and reveal this integrin as a target for the development of antiangiogenic and antimetastatic therapies.

Electronic supplementary material

The online version of this article (10.1186/s40409-018-0150-2) contains supplementary material, which is available to authorized users.

Normal tissue damage: its importance, history and challenges for the future

Sir Oliver Scott, a philanthropist and radiation biologist and, therefore, the epitome of a gentleman and a scholar, was an early Director of the BECC Radiobiology Research Unit at Mount Vernon. His tenure preceded that of Jack Fowler, with both contributing to basic, translational and clinical thought and application in radiation across the globe. With respect to this review, Fowler's name in particular has remained synonymous with the use of models, both animal and mathematical, that assess and quantify the biological mechanisms that underlie radiation-associated normal tissue toxicities. An understanding of these effects is critical to the optimal use of radiation therapy in the clinic; however, the role that basic sciences play in clinical practice has been undergoing considerable change in recent years, particularly in the USA, where there has been a growing emphasis on engineering and imaging to improve radiation delivery, with empirical observations of clinical outcome taking the place of models underpinned by evidence from basic science experiments. In honour of Scott and Fowler's work, we have taken this opportunity to review how our respective fields of radiation biology and radiation physics have intertwined over the years, affecting the clinical use of radiation with respect to normal tissue outcomes. We discuss the past and current achievements, with the hope of encouraging a revived interest in physics and biology as they relate to radiation oncology practice, since, like Scott and Fowler, we share the goal of improving the future outlook for cancer patients.

Platelet RNA signatures for the detection of cancer

Platelets are equipped with RNA processing machineries, such as pre-mRNA splicing, pre-miRNA processing, and mRNA translation. Since platelets are devoid of a nucleus, most RNA transcripts in platelets are derived from megakaryocytes during thrombocytogenesis. However, platelets can also ingest RNA molecules during circulation and/or interaction with other cell types. Since platelets were first described by Bizzozero in 1881, their well-established role in hemostasis and thrombosis has been intensively studied. However, in the past decades, the list of biological processes in which platelets play an important role keeps expanding. In this review, we discuss how platelet RNA biomarker signatures can be altered in the presence of cancer.

Liquid biopsy for lung cancer early detection

Molecularly targeted therapies and immune checkpoint inhibitors have markedly improved the therapeutic management of advanced lung cancer. However, it still remains the leading cause of cancer-related mortality worldwide, with disease stage at diagnosis representing the main prognostic factor. Detection of lung cancer at an earlier stage of disease, potentially susceptible of curative resection, can be critical to improve patients survival. Low-dose computed tomography (LDCT) screening of high-risk patients has been demonstrated to reduce mortality from lung cancer, but can be also associated with high false-positive rate, thus often resulting in unnecessary interventions for patients. Novel sensitive and specific biomarkers for identification of high-risk subjects and early detection that can be used alternatively and/or complement current routine diagnostic procedures are needed. Liquid biopsy has recently demonstrated its clinical usefulness in advanced NSCLC as a surrogate of tissue biopsy for noninvasive assessment of specific genomic alterations, thereby providing prognostic and predictive information. Different biosources from liquid biopsy, including cell free circulating tumor DNA (ctDNA), circulating tumor cells (CTCs), exosomes and tumor-educated platelets (TEPs), have also been widely investigated for their potential role in lung cancer diagnosis. This review will provide an overview on the circulating biomarkers being evaluated for lung cancer detection, mainly focusing on results from most recent studies, the techniques developed to perform their assessment in blood and other biologic fluids and challenges in their clinical applications.

Inflammatory interferon activates HIF-1α-mediated epithelial-to-mesenchymal transition via PI3K/AKT/mTOR pathway

BACKGROUND

Tumor microenvironments (TMEs) activate various axes/pathways, predominantly inflammatory and hypoxic responses, impact tumorigenesis, metastasis and therapeutic resistance significantly. Although molecular pathways of individual TME are extensively studied, evidence showing interaction and crosstalk between hypoxia and inflammation remain unclear. Thus, we examined whether interferon (IFN) could modulate both inflammatory and hypoxic responses under normoxia and its relation with cancer development.

METHODS

IFN was used to induce inflammation response and HIF-1α expression in various cancer cell lines. Corresponding signaling pathways were then analyzed by a combination of pharmacological inhibitors, immunoblotting, GST-Raf pull-down assays, dominant-negative and short-hairpin RNA-mediated knockdown approaches. Specifically, roles of functional HIF-1α in the IFN-induced epithelial-mesenchymal transition (EMT) and other tumorigenic propensities were examined by knockdown, pharmacological inhibition, luciferase reporter, clonogenic, anchorage-independent growth, wound-healing, vasculogenic mimicry, invasion and sphere-formation assays as well as cellular morphology observation.

RESULTS

We showed for the first time that IFN induced functional HIF-1α expression in a time- and dose- dependent manner in various cancer cell lines under both hypoxic and normoxic conditions, and then leading to an activated HIF-1α pathway in an IFN-mediated pro-inflammatory TME. IFN regulates anti-apoptosis activity, cellular metastasis, EMT and vasculogenic mimicry by a novel mechanism through mainly the activation of PI3K/AKT/mTOR axis. Subsequently, pharmacological and genetic modulations of HIF-1α, JAK, PI3K/AKT/mTOR or p38 pathways efficiently abrogate above IFN-induced tumorigenic propensities. Moreover, HIF-1α is required for the IFN-induced invasiveness, tumorigenesis and vasculogenic mimicry. Further supports for the HIF-1α-dependent tumorigenesis were obtained from results of xenograft mouse model and sphere-formation assay.

CONCLUSIONS

Our mechanistic study showed an induction of HIF-1α and EMT ability in an IFN-mediated inflammatory TME and thus demonstrating a novel interaction between inflammatory and hypoxic TMEs. Moreover, targeting HIF-1α may be a potential target for inhibiting tumor tumorigenesis and EMT by decreasing cancer cells wound healing and anchorage-independent colony growth. Our results also lead to rationale guidance for developing new therapeutic strategies to prevent relapse via targeting TME-providing IFN signaling and HIF-1α programming.

Tumor-fibroblast interactions stimulate tumor vascularization by enhancing cytokine-driven production of MMP9 by tumor cells

Advance-stage breast carcinomas include significant amounts of fibroblasts and infiltrating immune cells which have been implicated in tumor growth, recurrence, and response to therapy. The present study investigated the contribution of fibroblasts to tumor growth using direct tumor-fibroblast co-cultures and tumor xenograft models. Our findings revealed that fibroblasts enhance breast carcinoma growth by promoting the tumor vasculature via the MMP9-dependent mechanism. In tumor-fibroblast co-cultures, fibroblasts increased expression of TGF-β, TNF, and IL-1β cytokines in tumor cells. These cytokines cooperatively induced expression of matrix metalloproteinase MMP9 in tumor cells. Knockdown of MMP9 by shRNA significantly reduced tumor vascularization induced by fibroblasts. Mechanistically, our findings argue that expression of MMP9 in tumor cellsis regulated by crosstalk of TGF-β with TNF and/or IL-1β cytokines. The mechanism of this cooperative response did not involve cross-activation of the canonical signaling pathways as TGF-β did not activate RELA/p65 signaling, while TNF did not affect SMAD signaling. Instead, TGF-β and TNF cytokines co-stimulated MAP kinases and expression of JUN and JUNB, AP1 transcription factor subunits, which together with RELA/p65 were essential for the regulation of MMP9. Depletion of JUN and JUNB or RELA in tumor cells blocked the cooperative induction of MMP9 by the cytokines. Thus, our studies uncovered a previously unappreciated role of tumor-fibroblast interactions in the stimulation of tumor angiogenesis, and an essential role of the MAPK-AP1 axis in the cooperative up-regulation of the angiogenic driver MMP9 by cytokine crosstalk.

Palliative stenting for oesophagogastric cancer: tumour and host factors and prognosis

Objectives

Palliative self-expandable metallic stent (SEMS) insertion is common in patients not suitable for resection of oesophagogastric (OG) cancer. Factors which may determine survival, however, are not clear. The present study examined the relationship between tumour and host factors, including the systemic inflammatory response and survival of patients undergoing palliative SEMS insertion.

Methods

Patients with a diagnosis of OG cancer who were considered suitable for palliative SEMS only without systemic therapy were identified. Patient characteristics including Eastern Cooperative Oncology Group performance status, radiological stage and modified Glasgow Prognostic Score (mGPS: 0—C-reactive protein (CRP) ≤10 mg/L; 1—CRP >10 mg/L; 2—CRP >10 mg/L; albumin <35 g/L) were recorded prospectively. The relationship between such characteristics and 3-month survival was examined.

Results

203 patients were included in the final analysis. All patients died during follow-up, with median survival from diagnosis 75 days (IQR 47–157). 78% of patients were systemically inflamed (mGPS >1). On multivariate analysis, only poor performance status (HR 1.23, p=0.025), metastatic disease (HR 2.27, p<0.001) and mGPS (HR 1.25, p=0.021) were associated with shorter survival. The combination of performance status and mGPS stratified 3-month survival of patients without metastatic disease from 88% to 20% (p<0.001) and patients with metastases from 43% to 6% (p=0.059). Similar results were observed when analysis was restricted to patients with oesophageal and junctional cancer (M0: 83%–20%, p=0.008; M1: 33%–8%, p=0.082).

Conclusion

Performance status, metastatic disease and mGPS are independent predictors of survival in patients with OG cancer undergoing palliative SEMS insertion. These routinely available markers provide a rational system on which to base decisions regarding prognosis and treatment.

Kindlin-1 Promotes Pulmonary Breast Cancer Metastasis

In breast cancer, increased expression of the cytoskeletal adaptor protein Kindlin-1 has been linked to increased risks of lung metastasis, but the functional basis is unknown. Here, we show that in a mouse model of polyomavirus middle T antigen-induced mammary tumorigenesis, loss of Kindlin-1 reduced early pulmonary arrest and later development of lung metastasis. This phenotype relied on the ability of Kindlin-1 to bind and activate β integrin heterodimers. Kindlin-1 loss reduced α4 integrin-mediated adhesion of mammary tumor cells to the adhesion molecule VCAM-1 on endothelial cells. Treating mice with an anti-VCAM-1 blocking antibody prevented early pulmonary arrest. Kindlin-1 loss also resulted in reduced secretion of several factors linked to metastatic spread, including the lung metastasis regulator tenascin-C, showing that Kindlin-1 regulated metastatic dissemination by an additional mechanism in the tumor microenvironment. Overall, our results show that Kindlin-1 contributes functionally to early pulmonary metastasis of breast cancer.Significance: These findings provide a mechanistic proof in mice that Kindin-1, an integrin-binding adaptor protein, is a critical mediator of early lung metastasis of breast cancer. Cancer Res; 78(6); 1484-96. ©2018 AACR.

Metformin blocks myeloid-derived suppressor cell accumulation through AMPK-DACH1-CXCL1 axis

Purpose: Tumor development has been closely linked to tumor microenvironment, particularly in terms of myeloid-derived suppressive cells (MDSCs), a heterogeneous population of immature myeloid cells that protect tumors from elimination by immune cells. Approaches aimed at blocking MDSC accumulation could improve cancer clinical outcome. Experimental Design: We investigated that metformin suppressed MDSC migration to inhibit cancer progression. Primary tumor tissues were incubated with metformin, and proinflammatory chemokine production was measured. To study MDSC chemotaxis in vivo, BALB/C nude mice were injected subcutaneously with TE7 cells and treated with metformin. Migration of adoptively transferred MDSCs was analyzed using flow cytometry and immunohistochemistry. Results: The frequency of tumor-infiltrated polymorphonuclear (PMN)-MDSCs was increased compared to their circulating counterparts. There was a significant correlation between PMN-MDSCs accumulation in tumors and ESCC prognosis. Moreover, PMN-MDSCs displayed immunosuppressive activity in vitro. Treatment with metformin reduced MDSC migration in patients. Metformin inhibited CXCL1 secretion in ESCC cells and tumor xenografts by enhancing AMPK phosphorylation and inducing DACH1 expression, leading to NF-κB inhibition and reducing MDSC migration. Knockdown of AMPK and DACH1 expression blocked the effect of metformin on MDSC chemotaxis. Conclusions: A novel anti-tumor effect of metformin, which is mediated by reducing PMN-MDSC accumulation in the tumor microenvironment via AMPK/DACH1/CXCL1 axis.

Remote reprogramming of hepatic circadian transcriptome by breast cancer

Cancers adversely affect organismal physiology. To date, the genes within a patient responsible for systemically spreading cancer-induced physiological disruption remain elusive. To identify host genes responsible for transmitting disruptive, cancer-driven signals, we thoroughly analyzed the transcriptome of a suite of host organs from mice bearing 4T1 breast cancer, and discovered complexly rewired patterns of circadian gene expression in the liver. Our data revealed that 7 core clock transcription factors, represented by Rev-erba and Rorg, exhibited abnormal daily expression rhythm in the liver of 4T1-bearing mice. Accordingly, expression patterns of specific set of downstream circadian genes were compromised. Osgin1, a marker for oxidative stress, was an example. Specific downstream genes, including E2f8, a transcriptional repressor that controls cellular polyploidy, displayed a striking pattern of disruption, "day-night reversal." Meanwhile, we found that the liver of 4T1-bearing mice suffered from increased oxidative stress. The tetraploid hepatocytes population was concomitantly increased in 4T1-bearing mice, which has not been previously appreciated as a cancer-induced phenotype. In summary, the current study provides a comprehensive characterization of the 4T1-affected hepatic circadian transcriptome that possibly underlies cancer-induced physiological alteration in the liver.

Osteoblasts remotely supply lung tumors with cancer-promoting SiglecFhigh neutrophils

Bone marrow-derived myeloid cells can accumulate within tumors and foster cancer outgrowth. Local immune-neoplastic interactions have been intensively investigated, but the contribution of the systemic host environment to tumor growth remains poorly understood. Here, we show in mice and cancer patients (n = 70) that lung adenocarcinomas increase bone stromal activity in the absence of bone metastasis. Animal studies reveal that the cancer-induced bone phenotype involves bone-resident osteocalcin-expressing (Ocn⁺) osteoblastic cells. These cells promote cancer by remotely supplying a distinct subset of tumor-infiltrating SiglecF^high neutrophils, which exhibit cancer-promoting properties. Experimentally reducing Ocn⁺ cell numbers suppresses the neutrophil response and lung tumor outgrowth. These observations posit osteoblasts as remote regulators of lung cancer and identify SiglecF^high neutrophils as myeloid cell effectors of the osteoblast-driven protumoral response.

MTSS1 and SCAMP1 cooperate to prevent invasion in breast cancer

Cell-cell adhesions constitute the structural "glue" that retains cells together and contributes to tissue organisation and physiological function. The integrity of these structures is regulated by extracellular and intracellular signals and pathways that act on the functional units of cell adhesion such as the cell adhesion molecules/adhesion receptors, the extracellular matrix (ECM) proteins and the cytoplasmic plaque/peripheral membrane proteins. In advanced cancer, these regulatory pathways are dysregulated and lead to cell-cell adhesion disassembly, increased invasion and metastasis. The Metastasis suppressor protein 1 (MTSS1) plays a key role in the maintenance of cell-cell adhesions and its loss correlates with tumour progression in a variety of cancers. However, the mechanisms that regulate its function are not well-known. Using a system biology approach, we unravelled potential interacting partners of MTSS1. We found that the secretory carrier-associated membrane protein 1 (SCAMP1), a molecule involved in post-Golgi recycling pathways and in endosome cell membrane recycling, enhances Mtss1 anti-invasive function in HER2+/ER-/PR- breast cancer, by promoting its protein trafficking leading to elevated levels of RAC1-GTP and increased cell-cell adhesions. This was clinically tested in HER2 breast cancer tissue and shown that loss of MTSS1 and SCAMP1 correlates with reduced disease-specific survival. In summary, we provide evidence of the cooperative roles of MTSS1 and SCAMP1 in preventing HER2+/ER-/PR- breast cancer invasion and we show that the loss of Mtss1 and Scamp1 results in a more aggressive cancer cell phenotype.

Circulating miR-106b-3p, miR-101-3p and miR-1246 as diagnostic biomarkers of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most common liver cancer and second leading cause of cancer related death worldwide. Most HCCs occur in a damaged cirrhotic background and it may be difficult to discriminate between regenerative nodules and early HCCs. No dependable molecular biomarker exists for the early detection of HCC. MicroRNAs (miRNAs) have attracted attention as potential blood-based biomarkers. To identify circulating miRNAs with diagnostic potential in HCC, we performed preliminary RNAseq studies on plasma samples from a small set of HCC patients, cirrhotic patients and healthy controls. Then, out of the identified miRNAs, we investigated miR-101-3p, miR-106b-3p, miR-1246 and miR-411-5p in plasma of independent HCC patients' cohorts. The use of droplet digital PCR (ddPCR) confirmed the aberrant levels of these miRNAs. The diagnostic performances of each miRNA and their combinations were measured using Receiver Operating Characteristic (ROC) curve analyses: a classifier consisting of miR-101-3p, miR-1246 and miR-106b-3p produced the best diagnostic precision in plasma of HCC vs. cirrhotic patients (AUC = 0.99). A similar performance was found when the levels of miRNAs of HCC patients were compared to healthy controls (AUC = 1.00). We extended the analyses of the same miRNAs to serum samples. In serum of HCC vs. cirrhotic patients, the combination of miR-101-3p and miR-106b-3p exhibited the best diagnostic accuracy with an AUC = 0.96. Thus, circulating miR-101-3p, miR-106b-3p and miR-1246, either individually or in combination, exhibit a considerable potential value as diagnostic biomarkers of HCC.

Relationship between tumour PTEN/Akt/COX-2 expression, inflammatory response and survival in patients with colorectal cancer

In patients with colorectal cancer (CRC), local and systemic inflammatory responses have been extensively reported to associate with cancer survival. However, the specific signalling pathways responsible for inflammatory responses are not clear. The PTEN/Akt pathway is a plausible candidate as it may play a role in mediating inflammation via COX-2, and has been associated with cancer progression. This study therefore examined the relationship between tumour PTEN/Akt/COX-2 expression, inflammatory responses and survival in CRC patients using a tissue microarray.

In 201 CRC patients, activation of tumour-specific PTEN/Akt significantly associated with poorer CSS (12.0yrs v 7.3yrs, P=0.032), poorer differentiation (P=0.032), venous invasion (P=0.008) and peritoneal involvement (P=0.004). Patients were stratified for peri-nuclear expression of COX-2 to examine associations with inflammatory responses. In patients with absent peri-nuclear COX-2 expression, activation of tumour-specific PTEN/Akt significantly associated with poorer CSS (11.9yrs v 5.4yrs, P=0.001), poorer differentiation (P=0.018), venous invasion (P=0.003) and peritoneal involvement (P=0.001). However, no associations were seen with either the local or systemic inflammatory responses.

In CRC patients, tumour-specific PTEN/Akt pathway activation was significantly associated with poorer CSS, particularly when peri-nuclear COX-2 expression was absent. However, activation of the PTEN/Akt pathway appears not to be responsible for the regulation of inflammatory responses.

Reciprocal modulation of mesenchymal stem cells and tumor cells promotes lung cancer metastasis

Metastasis is a multi-step process in which direct crosstalk between cancer cells and their microenvironment plays a key role. Here, we assessed the effect of paired tumor-associated and normal lung tissue mesenchymal stem cells (MSCs) on the growth and dissemination of primary human lung carcinoma cells isolated from the same patients. We show that the tumor microenvironment modulates MSC gene expression and identify a four-gene MSC signature that is functionally implicated in promoting metastasis. We also demonstrate that tumor-associated MSCs induce the expression of genes associated with an aggressive phenotype in primary lung cancer cells and selectively promote their dissemination rather than local growth. Our observations provide insight into mechanisms by which the stroma promotes lung cancer metastasis.

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Distinct gene expression profiles distinguish normal lung and tumor-associated MSCs.

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MSCs induce EMT- and hypoxia-related genes in primary tumor cells and promote their metastatic potential.

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A 4-gene T-MSC signature is involved in MSC-induced metastasis promotion.

The tumor microenvironment, which includes mesenchymal stem cells (MSCs) among many other stromal cell types, plays a fundamental role in cancer metastasis. Although MSCs are suggested to participate in tumor progression, most studies thus far have been performed on bone marrow-derived MSCs and cancer cell lines. Using primary human pulmonary MSCs and paired lung cancer cells, we show that tumor cells modulate MSCs to acquire properties, including a four-gene signature, which allow them to promote tumor dissemination. Our results provide insight into the mutual cancer cell-stromal cell modulation that drives tumor dissemination.

The relationship between total and phosphorylated STAT1 and STAT3 tumour cell expression, components of tumour microenvironment and survival in patients with invasive ductal breast cancer

The aim of the present study was to examine the relationship between tumour cell expression of total and phosphorylated STAT1 (ph-STAT1) and STAT3 (ph-STAT-3), components of tumour microenvironment and survival in patients with invasive ductal breast cancer.

Immunohistochemical analysis of total and ph-STAT1, and STAT3 were performed on tissue microarray of 384 breast cancer specimens. Tumour cell expression of STAT1 and STAT3 at both cytoplasmic and nuclear locations were combined and identified as STAT1/STAT3 tumour cell expression. These results were related to cancer specific survival (CSS) and phenotypic features of the tumour and the host.

High ph-STAT1 and ph-STAT3 tumour cell expression were associated with increased ER (both P≤0.001) and PR (both P <0.05), reduced tumour grade (P=0.015 and P<0.001 respectively) and necrosis (both P=0.001). Ph-STAT1 was associated with increased general inflammatory infiltrate (P=0.007) and ph-STAT3 was associated with lower CD4+ infiltration (P=0.024). In multivariate survival analysis, only high ph-STAT3 tumour cell expression was a predictor of improved CSS (P=0.010) independent of other tumour and host-based factors.

STAT1 and STAT3 tumour cell expression appeared to be an important determinant of favourable outcome in patients with invasive ductal breast cancer. The present results suggest that STAT1 and STAT3 may affect disease outcome through direct impact on tumour cells, counteracting aggressive tumour features, as well as interaction with the surrounding microenvironment.

Immunological network analysis in HPV associated head and neck squamous cancer and implications for disease prognosis

Human papillomavirus-positive (HPV+) head and neck squamous cell cancer (HNSCC) exhibits a better prognosis than HPV-negative (HPV-) HNSCC. This difference may in part be due to enhanced immune activation in the HPV+ HNSCC tumor microenvironment. To characterize differences in immune activation between HPV+ and HPV- HNSCC tumors, we identified and annotated differentially expressed genes based upon mRNA expression data from The Cancer Genome Atlas (TCGA). Immune network between immune cells and cytokines was constructed by using single sample Gene Set Enrichment Analysis and conditional mutual information. Multivariate Cox regression analysis was used to determine the prognostic value of immune microenvironment characterization. A total of 1673 differentially expressed genes were functionally annotated. We found that genes upregulated in HPV+ HNSCC are enriched in immune-associated processes. And the up-regulated gene sets were validated by Gene Set Enrichment Analysis. The microenvironment of HPV+ HNSCC exhibited greater numbers of infiltrating B and T cells and fewer neutrophils than HPV- HNSCC. These findings were validated by two independent datasets in the Gene Expression Omnibus (GEO) database. Further analyses of T cell subtypes revealed that cytotoxic T cell subtypes predominated in HPV+ HNSCC. In addition, the ratio of M1/M2 macrophages was much higher in HPV+ HNSCC. The infiltration of these immune cells was correlated with differentially expressed cytokine-associated genes. Enhanced infiltration of B cells and CD8+ T cells were identified as independent protective factors, while high neutrophil infiltration was a risk enhancing factor for HPV+ HNSCC patients. A schematic model of immunological network was established for HPV+ HNSCC to summarize our findings.

Integrative analysis of imaging and transcriptomic data of the immune landscape associated with tumor metabolism in lung adenocarcinoma: Clinical and prognostic implications

Although metabolic modulation in the tumor microenvironment (TME) is one of the key mechanisms of cancer immune escape, there is a lack of understanding of the comprehensive immune landscape of the TME and its association with tumor metabolism based on clinical evidence. We aimed to investigate the relationship between the immune landscape in the TME and tumor glucose metabolism in lung adenocarcinoma. Methods: Using RNA sequencing and image data, we developed a transcriptome-based tumor metabolism estimation model. The comprehensive TME cell types enrichment scores and overall immune cell enrichment (ImmuneScore) were estimated. Subjects were clustered by cellular heterogeneity in the TME and the clusters were characterized by tumor glucose metabolism and immune cell composition. Moreover, the prognostic value of ImmuneScore, tumor metabolism and the cell type-based clusters was also evaluated. Results: Four clusters were identified based on the cellular heterogeneity in the TME. They showed distinct immune cell composition, different tumor metabolism, and close relationship with overall survival. A cluster with high regulatory T cells showed relative hypermetabolism and poor prognosis. Another cluster with high mast cells and CD4+ central memory T cells showed relative hypometabolism and favorable prognosis. A cluster with high ImmuneScore showed favorable prognosis. Multivariate Cox analysis demonstrated that ImmuneScore was a predictive prognostic factor independent of other clinical features. Conclusions: Our results showed the association between predicted tumor metabolism and immune cell composition in the TME. Our studies also suggest that tumor glucose metabolism and immune cell infiltration in the TME can be clinically applicable for developing a prognostic stratification model.

Commonly Occurring Cell Subsets in High-Grade Serous Ovarian Tumors Identified by Single-Cell Mass Cytometry

We have performed an in-depth single-cell phenotypic characterization of high-grade serous ovarian cancer (HGSOC) by multiparametric mass cytometry (CyTOF). Using a CyTOF antibody panel to interrogate features of HGSOC biology, combined with unsupervised computational analysis, we identified noteworthy cell types co-occurring across the tumors. In addition to a dominant cell subset, each tumor harbored rarer cell phenotypes. One such group co-expressed E-cadherin and vimentin (EV), suggesting their potential role in epithelial mesenchymal transition, which was substantiated by pairwise correlation analyses. Furthermore, tumors from patients with poorer outcome had an increased frequency of another rare cell type that co-expressed vimentin, HE4, and cMyc. These poorer-outcome tumors also populated more cell phenotypes, as quantified by Simpson's diversity index. Thus, despite the recognized genomic complexity of the disease, the specific cell phenotypes uncovered here offer a focus for therapeutic intervention and disease monitoring.

Bone Talk: Activated Osteoblasts Promote Lung Cancer Growth

Cancer cells can directly stimulate the generation and recruitment of tumor-supportive bone marrow-derived cells (BMDCs), including neutrophils, via secreted factors. A new study demonstrates that lung tumors also remotely activate bone-residing osteoblasts, which in turn promote neutrophil production. This is a multistep mechanism of establishing a supportive tumor microenvironment.

RET-mediated modulation of tumor microenvironment and immune response in multiple endocrine neoplasia type 2 (MEN2)

Medullary thyroid carcinomas (MTC) arise from thyroid parafollicular, calcitonin-producing C-cells and can occur either as sporadic or as hereditary diseases in the context of familial syndromes, including multiple endocrine neoplasia 2A (MEN2A), multiple endocrine neoplasia 2B (MEN2B) and familial MTC (FMTC). In a large fraction of sporadic cases, and virtually in all inherited cases of MTC, activating point mutations of the RET proto-oncogene are found. RET encodes for a receptor tyrosine kinase protein endowed with transforming potential on thyroid parafollicular cells. As in other cancer types, microenvironmental factors play a critical role in MTC. Tumor-associated extracellular matrix, stromal cells and immune cells interact and influence the behavior of cancer cells both in a tumor-promoting and in a tumor-suppressing manner. Several studies have shown that, besides the neoplastic transformation of thyroid C-cells, a profound modification of tumor microenvironment has been associated to the RET FMTC/MEN2-associated oncoproteins. They influence the surrounding stroma, activating cancer-associated fibroblasts (CAFs), promoting cancer-associated inflammation and suppressing anti-cancer immune response. These mechanisms might be exploited to develop innovative anti-cancer therapies and novel prognostic tools in the context of familial, RET-associated MTC.

Prognostic value of multiple cytokine analysis in colorectal cancer: a systematic review

The link between inflammation and outcome has been established in colorectal cancer through experimental evidence demonstrating an influential role of pro-inflammatory cytokines on tumour growth and progression. Furthermore, prognostic scores based on overall markers of systemic inflammation such as C-reactive protein and neutrophil count have been validated. Over recent years, an increasing number of inflammatory cytokines have been identified as prognostic predictors in colorectal cancer and the aim of this review was to evaluate the literature on the prognostic value of multiple cytokine measurement. The English language literature published since the year 2000 was searched using terms including, 'colorectal cancer', 'cytokines' and 'prognosis' through Medline, Embase and Scopus databases. Reports were screened by two independent reviewers and studies evaluating fewer than three cytokines were excluded. Quality assessments were performed in six domains before data extraction was undertaken in duplicate. Seven studies were found to evaluate multiple cytokines after 570 records were screened. The quality of these studies ranged from poor to moderate and were heterogeneous in terms of the patient population and the number and selection of cytokines tested. Four studies combined multiple cytokine levels into a single score and found them to be predictive of prognosis whereas the association between individual cytokines and outcome was not demonstrated consistently. The combination of multiple cytokine markers into a single prognostic score shows promise in colorectal cancer and further research is required to establish and validate such a score.