Tumor Stroma (tumor + stroma)

Distribution by Scientific Domains


Selected Abstracts


Mesenchymal stem cells enhance growth and metastasis of colon cancer

INTERNATIONAL JOURNAL OF CANCER, Issue 10 2010
Kei Shinagawa
Abstract Recently, mesenchymal stem cells (MSCs) were reported to migrate to tumor stroma as well as injured tissue. We examined the role of human MSCs in tumor stroma using an orthotopic nude mice model of KM12SM colon cancer. In in vivo experiments, systemically injected MSCs migrated to the stroma of orthotopic colon tumors and metastatic liver tumors. Orthotopic transplantation of KM12SM cells mixed with MSCs resulted in greater tumor weight than did transplantation of KM12SM cells alone. The survival rate was significantly lower in the mixed-cell group, and liver metastasis was seen only in this group. Moreover, tumors resulting from transplantation of mixed cells had a significantly higher proliferating cell nuclear antigen labeling index, significantly greater microvessel area and significantly lower apoptotic index. Splenic injection of KM12SM cells mixed with MSCs, in comparison to splenic injection of KM12SM cells alone, resulted in a significantly greater number of liver metastases. MSCs incorporated into the stroma of primary and metastatic tumors expressed ,-smooth muscle actin and platelet-derived growth factor receptor-, as carcinoma-associated fibroblast (CAF) markers. In in vitro experiments, KM12SM cells recruited MSCs, and MSCs stimulated migration and invasion of tumor cells through the release of soluble factors. Collectively, MSCs migrate and differentiate into CAFs in tumor stroma, and they promote growth and metastasis of colon cancer by enhancing angiogenesis, migration and invasion and by inhibiting apoptosis of tumor cells. [source]


Immune manipulation of advanced breast cancer: An interpretative model of the relationship between immune system and tumor cell biology

MEDICINAL RESEARCH REVIEWS, Issue 3 2009
Andrea Nicolini
Abstract This review summarizes some recent clinical immunological approaches with cytokines and/or antibodies for therapy of advanced breast cancer. It considers the recent advances in genetics and molecular tumor biology related to impaired immunosurveillance involving cytokines and growth factors to explain clinical results. Evasion of the host immune attack might be induced by the following groups of mechanisms: (a) tumor dependent (genomic instability, HLA class I antigen abnormalities, upregulation of fetal type nonclassical HLA class I molecules, epitope immunodominance, apoptosis inhibition by defective death receptor signaling, apoptosis of activated T cells, tumor cannibalism and constitutive activation of signal transducer, and activator of transcription-3 (Stat 3) and nuclear factor-,B (NF-kB) signaling); (b) host dependent (CD4+CD25+ regulatory T cells (T reg), CD4+ T cells anergy, Th2 antitumor immunity diversion and myeloid suppressor cells); (c) tumor and host dependent (lack of co-stimulation molecules, immunosuppressive cytokines (vascular endothelial growth factor (VEGF), interleukin (IL)-10, prostaglandin (PG)E2, transforming growth factor (TGF)-,)). Cytokines and growth factors are involved in virtually all three types of mechanisms. These mechanisms are integrated with the current knowledge of tumor growth and inhibited apoptosis primarily mediated by cytokines and growth factors to propose an interpretation of the relationships among tumor cells, tumor stroma, and tumor-infiltrating lymphocytes. Tumor growth, defective immunorecognition and immunosuppression are the three principal effects considered responsible for immune evasion. © 2008 Wiley Periodicals, Inc. Med Res Rev, 29, No. 3, 436-471, 2009 [source]


Pericytes and vessel maturation during tumor angiogenesis and metastasis,

AMERICAN JOURNAL OF HEMATOLOGY, Issue 8 2010
Ahmad Raza
Despite promising results in preclinical and clinical studies, the therapeutic efficacy of antiangiogenic therapies has been restricted by a narrow focus on inhibiting the growth of endothelial cells. Other cell types in the tumor stroma are also critical to the progression of cancer, including mural cells. Mural cells are vascular support cells that range in phenotype from pericytes to vascular smooth muscle cells. Although the role of pericytes and pericyte-like cells in the pathophysiology of cancer is still unclear, evidence indicates that aberrations in pericyte,endothelial cell signaling networks could contribute to tumor angiogenesis and metastasis. The purpose of this review is to evaluate critically recent evidence on the role of pericytes in tumor biology and discuss potential therapeutic targets for anticancer intervention. Am. J. Hematol. 85:593,598, 2010. © 2010 Wiley-Liss, Inc. [source]


Nuclear androgen receptors recur in the epithelial and stromal compartments of malignant and non-malignant human prostate tissue several months after castration therapy

THE PROSTATE, Issue 12 2007
Pernilla Wikström
Abstract BACKGROUND As changed paracrine support from androgen receptor (AR)-positive cells in the prostate stroma contribute to castration-induced glandular involution, we examined if the subsequent relapse to androgen-independent epithelial cell growth could be related to reactivation of AR signaling in the stroma. MATERIALS AND METHODS Human prostate tissue taken before, within 14 days, and at suspected local tumor relapse after surgical castration therapy was immunostained for AR. RESULTS Castration initially decreased nuclear AR staining in epithelial and stroma cells, in both tumor and non-malignant tissue, but after some months, it reappeared. CONCLUSIONS Local tumor relapse was associated with reappearance of nuclear AR not only in tumor epithelial cells but also in the tumor stroma. Reappearance of nuclear AR in non-malignant prostate cells may be a physiological response to long-term systemic androgen ablation that could influence tumor growth. Prostate 67: 1277,1284, 2007. © 2007 Wiley-Liss, Inc. [source]


The prognostic value of intraepithelial and stromal CD3-, CD117- and CD138-positive cells in non-small cell lung carcinoma

APMIS, Issue 5 2010
KHALID AL-SHIBLI
Al-Shibli K, Al-Saad S, Andersen S, Donnem T, Bremnes RM, Busund L-T. The prognostic value of intraepithelial and stromal CD3-, CD117- and CD138-positive cells in non-small cell lung carcinoma. APMIS 2010; 118: 371,82. The major value of prognostic markers in potentially curable non-small cell lung carcinoma (NSCLC) should be to guide therapy after surgical treatment. Although tumor-infiltrating T lymphocytes and plasma cells have been documented in NSCLC, a clear association with clinical outcome, especially for the stromal component, has not been well established. The aim of this study was to elucidate the prognostic significance of these cells/markers in the epithelial and stromal compartments of NSCLC. Tissue microarrays from 335 resected, stage I-IIIA, NSCLC were constructed by duplicate cores from viable neoplastic epithelial and stromal areas. Immunohistochemistry was used to evaluate the infiltration of CD3+, CD117+ as well as CD138+ cells in epithelial and stromal areas. In univariate analyses, increasing numbers of stromal CD3+ (p = 0.001) and epithelial CD3+ cells (p = 0.004) correlated significantly with an improved disease-specific survival. No such relation was noted with CD3+ or CD117+ cells. In the multivariate analysis, stromal CD3+ cells was an independent prognostic factor for disease-specific survival (HR 1.925, CI 1.21,3.04, p = 0.005). Increased presence of the pan T-cell marker, CD3, which is an independent factor, correlates with improved clinical outcome in NSCLC. This prognostic impact of T cells is clearer in the tumor stroma. Neither plasma cells nor mast cells were prognostic indicators in our cohort. [source]


Dendritic cell infiltration pattern along the colorectal adenoma-carcinoma sequence,

APMIS, Issue 6 2008
APING YUAN
We have previously reported that the dendritic cell (DC) functional index cytokine interleukin-12 was significantly decreased in colorectal carcinoma (CRC) tissues. In this study, the DC infiltration pattern and the density of mature DCs (mDCs; labeled by anti-CD83 and anti-CD208) and immature DCs (iDCs; labeled by anti-CD1,) were characterized using immunohistochemistry (IHC) in tissue samples from 23 patients with CRC, 33 patients with colorectal adenoma (CRA), and 19 healthy controls. In addition, the DC function inhibitor cyclooxygenase-2 (COX-2) and the downstream signal molecule prostaglandin E2 (PGE2) and related receptors EP2/EP4 were measured by quantitative real-time PCR and double immunofluorescence staining. The IHC analyses revealed changed densities of mDCs and iDCs in the tumor microenvironment; in CRA and CRC, the density of mDCs was decreased, but the density of iDCs was gradually increased. Furthermore, the distribution patterns of DCs were also altered. In CRA, mDCs were abundantly distributed in the subepithelial stroma of the adenomatous mass. In CRC, the distribution of mDCs in the tumor stroma was not homogeneous, and mDCs residing in the stroma at invading edges were more frequently found compared with in the intratumoral stroma (P<0.05). Increased iDCs were found in the intratumoral mass in CRC, and some infiltrated into the malignant epithelium. By quantitative real-time PCR, a gradually increased level of COX-2 mRNA was demonstrated in the local tissues along the adenoma-carcinoma sequence, and double immunofluorescence staining showed a colocalization of PGE2 receptors EP2/EP4 with mDCs in the stroma of CRC. In conclusion, our current findings revealed an altered DC infiltration pattern along the adenoma-carcinoma sequence; gradually increased COX-2 expression might contribute to the DC functional defect. [source]


Role of tumor-derived proinflammatory cytokines GM-CSF, TNF-,, and IL-12 in the migration and differentiation of antigen-presenting cells in cervical carcinoma

CANCER, Issue 3 2007
Henry J.M.A.A. Zijlmans MD
Abstract BACKGROUND. Proinflammatory cytokines are important in modifying the activity, differentiation, and migration of antigen-presenting cells and may influence the survival of cancer patients. The study assessed whether GM-CSF, TNF-,, and IL-12, produced by cervical cancer cells, are important for the activity, differentiation, and migration of antigen-presenting cells. METHODS. In 90 patients with cervical carcinoma the number of monocytes/tumor-associated macrophages (TAM), mature dendritic cells (DC), and Langerhans cells (LHC) was determined using immunohistochemistry. An RNA in situ hybridization technique was used to measure the expression level of GM-CSF, TNF-,, IL-12p35, and IL-12p40. RESULTS. TAM were detected intraepithelial as well as in the stroma of the tumor. LHC were only detected intraepithelial and mature DC only in the tumor stroma. The number of TAM correlated positively with the number of mature DC. The expression levels of GM-CSF and TNF-, correlated positively with the number of TAM and DC. TNF-, showed a negative correlation with the number of LHC. A significant correlation between the expression of functional IL-12 (IL-12p40) and stromal TAM was found. The expression of GM-CSF, TNF-,, and IL-12p40 did not correlate significantly with disease-free survival. However, high IL-12p40 expression was associated with a favorable cumulative overall survival. CONCLUSIONS. The results suggest that GM-CSF as well as TNF-,, produced by cervical carcinoma cells, may play a role in the differentiation of monocytes into mature DC. Furthermore, TNF-, may influence the migration of LHC from the tumor. Cancer 2007;109:556,565. © 2007 American Cancer Society. [source]


Molecular links between tumor angiogenesis and inflammation: inflammatory stimuli of macrophages and cancer cells as targets for therapeutic strategy

CANCER SCIENCE, Issue 8 2008
Mayumi Ono
Both inflammation and angiogenesis are exacerbated by increased production of chemokines/cytokines, growth factors, proteolytic enzymes, proteoglycans, lipid mediators and prostaglandins. It has been reported that approximately 15,20% of all malignancies are initiated or exacerbated by inflammation. Initiation and progression of cancer are also closely linked to angiogenesis. Infiltration of macrophages is a dramatic and common feature of inflammation, angiogenesis and cancer, and has been recently highlighted in an attempt to develop novel strategies for treating cancer. The recruitment and infiltration of macrophages in the tumor microenvironment activates them to support the malignant progression of cancer cells, and these macrophages are called tumor-associated macrophages. In a model of experimental angiogenesis using mouse corneas, macrophages infiltrated tissue in response to inflammatory cytokines and produced chemokines and angiogenesis-promoting factors, such as vascular endothelial growth factor-A, interleukin-8, matrix metalloproteinases, prostanoids and reactive oxygen species. Moreover, in a cancer xenograft model, inflammatory stimuli by a representative inflammatory cytokine, interleukin-1,, enhanced tumor growth and angiogenesis with infiltration and activation of macrophages. Co-culture of cancer cells with macrophages synergistically stimulated production of various angiogenesis-related factors when stimulated by the inflammatory cytokine. This inflammatory angiogenesis in both mouse cornea and a tumor model was mediated, in part, by activation of nuclear factor ,B and activator protein 1 (Jun/Fos). Administration of either nuclear factor ,B-targeting drugs or cyclooxygenase 2 inhibitors or depletion of macrophages could block both inflammatory angiogenesis and tumor angiogenesis. Thus, both inflammatory and angiogenic responses in tumor stroma could be targets for development of anticancer therapeutic drugs. (Cancer Sci 2008; 99: 1501,1506) [source]


Signaling networks guiding epithelial,mesenchymal transitions during embryogenesis and cancer progression

CANCER SCIENCE, Issue 10 2007
Aristidis Moustakas
Epithelial,mesenchymal transition (EMT) describes the differentiation switch between polarized epithelial cells and contractile and motile mesenchymal cells, and facilitates cell movements and generation of new tissue types during embryogenesis. Many secreted polypeptides are implicated in the EMT process and their corresponding intracellular transduction pathways form highly interconnected networks. Transforming growth factor-,, Wnt, Notch and growth factors acting through tyrosine kinase receptors induce EMT and often act in a sequential manner. Such growth factors orchestrate the concerted regulation of an elaborate gene program and a complex protein network, needed for establishment of new mesenchymal phenotypes after disassembly of the main elements of epithelial architecture, such as desmosomes, as well as tight, adherens and gap junctions. EMT of tumor cells occurs during cancer progression and possibly generates cell types of the tumor stroma, such as cancer-associated myofibroblasts. EMT contributes to new tumor cell properties required for invasiveness and vascular intravasation during metastasis. Here we present some of the current mechanisms that mediate the process of EMT and discuss their relevance to cancer progression. (Cancer Sci 2007; 98: 1512,1520) [source]