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Cell Structure & Tumor Microenvironment Semra Aygun-Sunar, PhD Department of Cell Stress Biology [email protected] RPN-530 Oncology for Scientist-I October 3, 2013 Reading Book • “The Biology of Cancer”, Chapter 13 Robert Weinberg, Garland Science, 2006 • “Molecular Biology of the Cell” (Fifth Edition). Bruce Alberts, Alexander Johnson, Julian Lewis, Martin Raff, Keith Roberts, Peter Walter; 2008 Review • Hanahan & Weinberg, Hallmarks of Cancer: the next generation. Cell. 2011. 144: 646-674 Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 2 Overview of this lecture • Cells & cell theory • Studying of cells using microscopes • Structure and function of specific components include mitochondria, golgi, endoplasmic reticulum, cytoskeleton, extracellular matrix….. • Cancer cells • Tumor microenvironment: ! “Hypoxia” and “stromal cells” • Communication of cells with the tumor microenvironment ! Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 3 Cell “is the functional and smallest unit in every organism ” • The cell was first discovered by Robert Hooke (in 1665). • The cell theory was developed by Matthias J. Schleiden, Theodor Schwann and Rudolph Virchow (Ref: The Molecular Probes® Handbook-11th Edition, 2010, Invitrogen) Main principles of the cell theory • All living organisms are composed of cell(s). • Cells are the essential unit of structure and function in organisms • Cells are produced through the division of pre-existing cells (mitosis) Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 4 Studying Cells Light microscopy • uses visible light (ranges from 0.4 µm (for violet) to 0.7 µm (for deep red) that transmitted through or reflected from specimen • can view living cell to see their compartments • gives 1,000X magnification Ø Types of light microscopes 1. Bright field microscopy Passes light directly through specimen 2. Dark-field microscopy Light scattered by specimen 3. Phase-contrast microscopy Alter light waves to enhance the view of specimen 4. Differential interference contrast microscopy (DIC or Nomarski) Give specimens a 3D appearance The same fibroblast cell in culture shown using different types of light microcopies. Ref: “Molecular Biology of The Cell”, 5th edition. Alberts et al., 2008. Chapter 9, p.584 Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 5 Studying Cells Electron microscopy • uses beam of highly energetic electron to illuminate the specimen • has high magnification and high resolution TEM vs SEM cells must be dead and specimen require specifically preparations: can be cut/sectioned or T coated in gold metal Ø Types of electron microscopes ! Transmission Electron Microscopy (TEM) • uses the electrons that pass through specimen • is used for analyzing sections • shows only structure of cell • gives a 2D views • gives 1,000-500,000X magnification ! Scanning Electron Microscopy (SEM) • uses the electrons reflected from a specimen • is used for analyzing surface of the specimen • shows defined organelles inside cell • gives a 3D views • gives 10-300,000X magnification Cell Structure & Tumor Microenvironment E M S E M Cilia lining the trachea under TEM and SEM http://www.med.nus.edu.sg/ant/ histonet/tacsem/tac20.sem.gif RPN-530 Oncology for Scientist-I 6 Studying Cells Fluorescent molecules • absorb light at one wavelength called as Excitation, and emit it at another long wavelength called as Emission Chlorophyll has endogenous auto-fluorescence Fluorescent protein (GFP), Fluorescent probes are used to study the organization and function of living organism. Fluorescence probes Protein probe Ex (nm) Em (nm) Em color FITC 488 525 Green Nucleic acid probe Ex (nm) Em (nm) Em color DAPI 350 470 Blue Hoechst 33342 343 483 Blue Stably transfected human cervix carcinoma HeLa cells expressing GFP http://www.evrogen.com/products/ TurboGFP/ TurboGFP_Detailed_description.shtml Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 7 Studying Cells Fluorescence microscopy • exposes specimen to ultraviolet, violet, or blue light • excites and detects Fluorescent materials Epithelial cells stained with DAPI (blue) and two antibodies (green and red) via immunofluorescence Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 8 Studying Cells Confocal microscopy • is used with Fluorescent specimens • has two parts: optical sectioning and 3D-reconstraction -- takes a series of images to record -- computer generate a movie showing the 3D rotation of the image Confocal fluorescence microscopy of focal adhesion and actin cytoskeleton in COS-7 cells revealed with triple labeling using TRITCconjugated phalloidin, anti-Vinculin and DAPI. http://www.millipore.com/antibodies/flx4/ cell_structure&tab1=5&tab2=3#tab2=3:tab1=5 Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 9 Studying Cells Wide-field epifluoresence vs Confocal microscopy microscopy • gives nice images that have in-focus • gives very nice images that light have both in-focus and out-focus • does performs optical sectioning of light thick samples, •works with very thin specimens • is ability to control depth of field, or when a thick specimen is cut • provides 3D-image reconstruction, into sections. • detects very weak fluorescent signals, • generates high-resolution images, • has more color possibilities. http://www.itg.uiuc.edu/ technology/atlas/ microscopy/confocal.htm Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 10 Types of Cells 1. Prokaryotic cells: Archae and bacteria (no nucleus, no membrane-bound organelle, contain primitive cytoskeleton and circular-shaped DNA) 2. Eukaryotic cells: Protists, fungi, plants, animal (including human) (contain various membrane-bound organelles, cytoskeleton, chromatin and chromosome) Prokaryotic cell Cell Structure & Tumor Microenvironment vs Eukaryotic cell RPN-530 Oncology for Scientist-I 11 Plasma membrane (or cell membrane) Ø Structure • Fluid Mosaic Model • Phospholipid bilayer (Hydrophilic polar heads face outside and hydrofobic nonpolar tails face each other) • Contains integral (embedded in the membrane) and peripheral proteins (found on the inner membrane surface) Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 12 Plasma membrane ØFunction • Separates cell contents from environment • Serves as a diffusion barrier ! Regulation of transport by Passive transport includes ! Diffusion (“Osmosis” and “Dialysis”) or Active transport • Detection of signals • Cell-cell communication • Cell identity • Helps in cell movement Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 13 The major intracellular compartments of cell: “Organelles” Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 14 Animal Cell Organelles Nucleus Ø Structure I. Nuclear envelope * Composed of inner and outer membrane separated by perinuclear space * Has nuclear pores which connect with ER II. Nucleoplasm * Fluid of the nucleus III. Nucleolus * Not separated by membrane * is area of formation of ribosomal RNA, * is area of condensed DNA and chromatin DNA is tightly packaged up into nucleus! Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 15 Animal Cell Organelles Nucleus “contains the genetic information of the cell” Ø Function * Storage of genetic material (DNA) * Production of messenger RNA and ribosomes that needed for protein synthesis. * Storage of proteins and RNA in the nucleolus. * During the cell division, chromatins are arranged into chromosomes in the nucleus. * Function in selective transportation of regulatory factors and energy molecules through nuclear pores. Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 16 Animal Cell Organelles Mitochondria “ Energy producing organelle” Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 17 Animal Cell Organelles Mitochondria Ø Structure • Surrounded by 2 membranes: - smooth outer membrane (permeable) - folded inner membrane (impermeable) with layers called “cristae” • Contain two internal compartments: - mitochondrial matrix is within the inner membrane (contain ribosomes mitochondrial DNA (mtDNA) and enyzmes) - intermembrane space is located between the two membranes mtDNA: The structure of mitochondria. Ref:microbewiki.kenyon.edu/index.php/ Mitochondria Cell Structure & Tumor Microenvironment • inherited from mother • not protected by histones RPN-530 Oncology for Scientist-I 18 Animal Cell Organelles Mitochondria Function: Oxidative phosphorylation”--ATP synthesis Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 19 Animal Cell Organelles Mitochondria Function: Reactive Oxygen Species (ROS)/ Free radical generation Ref: Murphy MP. Biochem J, 2009 Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 20 Animal Cell Organelles Mitochondria Function: Regulation of apoptotic death and cell growth Apaf-1: Apoptotic protease activating factor 1 Ref: http://www.reading.ac.uk/nitricoxide/intro/apoptosis/mito.htm Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 21 Animal Cell Organelles Endoplasmic reticulum (ER) “cell’s internal membrane system” Ø Structure Cisternae • Cisternae (sac-like structures) • Cisternal space (or lumen) • ER membrane is continuous with nuclear envelope Ø Types of ER • Smooth-type (SER) : •Ribosome-free •Contains enzyme for lipid biosynthesis •Involved in attachment of receptors on cell membrane proteins • Rough-type (RER) : •Ribosomes embedded in surface •Involved in protein synthesis Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 22 Animal Cell Organelles Endoplasmic reticulum (ER) ØFunction • Protein folding, modification and secretion • Cellular protein quality control by extracting and degrading unfolded proteins (known as a ER-associated protein degradation-ERAD) • Lipid and sterol biosynthesis • Storage of calcium ions in the ER lumen and their regulated release into the cytosol (calcium homeostasis) • Detoxification of drugs • Core oligosaccharide biosynthesis • Apoptosis Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 23 Major responses to ER stress http://www.pdbj.org/eprots/index_en.cgi?PDB%3A2RIO Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 24 Animal Cell Organelles Golgi Apparatus Ø Structure • is made up numerous group of flat membranes called cisternea forming a sac Cisternea: * a complex network of tubules and vesicles are located at the edges of cisternea •help proteins and cytoplasmic components travel between different parts of the cell • has three regions: --- Cis face (near to ER) Receive transport vesicles from ER --- Trans face (far away from ER) Packages the material in vesicles and send outside of Golgi --- Golgi stack (between these two region) Main processing area Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 25 Animal Cell Organelles ØFunction Golgi Apparatus • Receives, sorts, modifies, packs and ships the proteins • Produce membrane packages called vesicles • Protects cells from apoptosis Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 26 Animal Cell Organelles Ø Structure Lysosomes • are membrane enclosed vesicles (spherical bodies about 50-70 nm in diameter) • arise from the golgi apparatus • are found in all animal cells such as white blood cells. • contain hydrolytic enzymes that digest & destroy macromolecules • two types of lysosomes: --- Peroxisomes: catalases & oxidases --- Proteosomes: proteases- cathepsin Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 27 Animal Cell Organelles Lysosomes-“suicide bags” and “recycling” Ø Function •Destroy invading bacteria or viruses (Phagocytosis) •Degrade older or damaged organelles (Autophagy) •Degrade macromolecules (Endocytosis) Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 28 Cytoskeleton “the movers and shapers in the cell” is found underlying the cell membrane in the cytoplasm Major Structures of the Cytoskeleton I. Actin filaments (or Microfilament) Microfilament structure and assembly http://micro.magnet.fsu.edu/cells/microfilaments/microfilaments.html * occur in every cell * composed of polymerased actin proteins * interact specifically with myosin helical polymers made of actin flexible, organized into 2D networks and 3D gels * function in cell movement and cellular contraction Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 29 Major Structures of the Cytoskeleton II. Microtubules Microtubule helical structure http://micro.magnet.fsu.edu/cells/microfilaments/microfilaments.html III. Intermediate filaments * composed of polymerased alpha and beta-tubulin * rigid, long, straight, holo tupe * length: 200 nm-25 µm * are used for centrioles •structural support of Cilia and Flagella •Involved in the movement of the materials within the cells * occur only in animal cells * composed of polymerased keratin proteins * rope-like structure * size: 8 -12 nm * provide structural stability Intermediate filament structure http://micro.magnet.fsu.edu/cells/microfilaments/microfilaments.html Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 30 Cytoskeleton http://ccaoscience.wordpress.com/notes/protein-structureswithin-the-cell/ Cell Structure & Tumor Microenvironment Function * Cell shape, * Cell polarity * Cell movement: -muscle contraction via actin filaments and myosin proteins -Flagella -Cilia * Cell cycle: Cell division and chromosomal separation by actin and tubulin cytoskeletal structures * Cell adhesion * Phagocytosis (by actin filaments) * Wound healing RPN-530 Oncology for Scientist-I 31 Extracellular matrix (ECM) is the defining feature of connective tissue in animals Epithelial cells Basement membrane Endothelium lining the capillary Connective tissue with Interstitial matrix Fibroblasts • • • http://en.wikipedia.org/wiki/ Extracellular_matrix is made up of Adhesive glycoproteins (fibronectin and laminin), Structural proteins (collagen and elastin) and Polysaccharides (glycosaminoglycans, proteoglycans) includes the interstitial matrix and basement membrane consisting of various cell types (i.e. fibroblasts, epithelial cells) and secreted proteins (cytokines) Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 32 Extracellular matrix (ECM) Ø Function • Cell shape, • Cell attachment, • Adhesion, • Migration (example: wound healing), • Cell proliferation, • Polarity, • Differentiation, • Survival & apoptosis, • Motility, • Management of growth factors, • Embryonic development. Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 33 Apical Epithelial Cells & Mesenchymal cells Lateral Basal • are polygonal in shape • have three membrane domains: apical, lateral and basal, • have adherens junctions • have tight junctions between apical and lateral domains, • express cell-cell adhesion markers such as E-cadherin, • lack of mobility. Cell Structure & Tumor Microenvironment • are fairly uniform small spindleshaped cells, • do not make mature cell-cell contacts, and can invade through the ECM, • are connected to other cells within a 3D- cellular network, • bipolar • express markers such as Ncadherin, Twist, snail, fibronectin • can migrate easily RPN-530 Oncology for Scientist-I 34 Epithelial-mesenchymal transition (EMT) • is characterized by loss of E-cadherin, disruption of cell adhesion, and induction of cell motility and invasion to convert a mesenchymal phenotype • function in embryonic development, organ formation, tissue regeneration, wound healing, organ fibrosis and cancer progression and metastasis. Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 35 Cell-cell adhesion Cadherins Homotypic cell adhesion by • are transmembrane proteins • mediate Ca+2-dependent cell- E-cadherin within the epithelium. cell adhesion • interact in a zipper-like fashion • stabilized by catenin complex • are cell type specific Several types of cadherins: * E-cadherin (epithelial) * P-cadherin (placental) * N-cadherin (neuronal) (Ref: Mohamet et al., Journal of Oncology, 2011) Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 36 Cell-cell adhesion “intercellular junctions” Plasma membrane Intracellular space Tight junction proteins Tight junction Plasma membrane Protein filaments Intercellular plaques Intracellular space Desmosome Intracellular space Plasma membrane Protein channels Connexons Gap junction Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Cell Structure & Tumor Microenvironment • Tight junction: - fused membranes of adjacent cells - form a continuous belt around cells - impermeable - ex: intestine, kidneys, bladder, epithelium of skin • Desmosomes - fastening adjacent cells together by connecting cell membrane to cytoskeleton proteins - binding spots between cells with cadherins -ex: skin, heart • Gap junction -Transmembrane proteins called connexons joint together to make a channel. - allow small molecules to pass directly from cell to cell -ex: heart muscle, animal embryos. (in heart muscle, the flow of ions through gap junctions coordinates the contraction) RPN-530 Oncology for Scientist-I 37 Cell-ECM adhesion Cell adhesion molecules-”Integrins” • are transmembrane heterodimeric cell-surface molecules • are receptors for ECM • are concentrated in cell at specific zone called Focal adhesions • are important for adhesion to ECM and transmembrane signaling • function as a link between ECM and the actin cytoskeleton • are important for cell growth The regulation of the extracellular binding activity of a cell's integrins Ref: Molecular Biology of the Cell, 4th edition Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 38 Tumor types Bening (non-cancerous) tumor vs malignant (cancerous) tumor Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 39 Tumors as 'wounds that do not heal' Normal skin tissue Cell Structure & Tumor Microenvironment Invasive carcinoma RPN-530 Oncology for Scientist-I 40 Cancer classifications Based on the location or origin of the malignant tumor Carcinoma Malignant tumors of epithelial cells Sarcoma Lymphoma Malignant tumors Malignant tumors of lymphocytes of supporting tissue (non-epithelial tumors: mesenchymal origin) Solid tumor Cell Structure & Tumor Microenvironment Leukemia Malignant tumors of blood cells Non-solid tumor RPN-530 Oncology for Scientist-I 41 Normal Cells vs Cancer Cells Microscopic appearance of cancer cells Mammary gland http://www.gfmer.ch/ selected_images_v2/detail_list.php? cat1=2&cat2=8&cat3=0&cat4=3&styp e=n Mammary carcinoma http://www.hindawi.com/ journals/ijol/2011/187623/fig1/ Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 42 Common characteristics of cancer cells • Uncontrolled cellular proliferation • Unbalanced cell division • Loss of apoptosis • Loss of special function (abnormal organelles and cell components and high rate of differentiation) • Abnormal vessel wall structure • Tissue invasion & metastasis • Angiogenesis • High glycolytic rate • Hypoxia Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 43 Nuclear structure in cancer cells Normal N e ucl oli Nuclear Nuclear lamina matrix PML CancercPoerinuc mp leo artm la ent r PML: Promyelocytic leukaemia NMP: nuclear matrix proteins NMP (Ref: Zink et al., Nature reviews, 2004) heterochromatin • Single and small nucleus & nucleolus • Fine chromatin granules in the nucleus • Clear nuclein stain • The smooth nuclear boarder • Stain artifact in one cell where another small white blood cell overlaps. Cell Structure & Tumor Microenvironment • Multiple and large nucleolus & nuclei • Large chromatin clumps in the nucleus • The dark staining of the nucleus and irregular nuclear boarder. • Nuclei can become irregular and begin to fold • PML bodies can mislocalized. • Specific NMPs are absent • Perinuclear compartment is present RPN-530 Oncology for Scientist-I 44 Mitochondria in cancer cells • mtDNA mutations inhibit oxidative phosphorylation: Increase ROS level and tumor cell proliferation Apoptosis-resistant mitochondria and cancer Ref: Indran et al., BBA, 2011 mitochondrial membrane permeabilization (MMP) permeability transition pore complex (PTPC) HKII: hexokinase II •Crosstalk between nucleus and mitochondria contribute to oncogenesis and tumor progression Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 45 UPR & ER stress in cancer cells http://www.hindawi.com/isrn/cell.biology/2013/256404/fig1/ Ref: Wang et al., Am J Transl Res, 2010 Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 46 Lysosome alterations & Autophagy in cancer cells Normal Cancer Lysosomes in normal versus cancer cells. Visualization of the lysosomal compartment (using lysosome-associated membrane protein 1) monoclonal antibodies, red) and the actin cytoskeleton (using anti-β-actin monoclonal antibodies, green) in murine embryonic fibroblasts. Note the perinuclear and peripheral localization of lysosomes in control and transformed cells, respectively. Defects in lysosome increase expression and altered trafficking of lysosomal enzymes participates in tissue invasion, angiogenesis and lysosomal death pathway. Autophagy act as both a “tumor suppressor” by preventing the accumulation of damaged proteins and organelles and as a “mechanism of cell survival” that can promote the growth of established tumors. Ref: Kroemer and Jäättelä nature Reviews, 2005, 5: 886-897 Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 47 Plasma membrane structure in cancer cells Komizu et al, Changes in the plasma membrane fluidity of tumor cells may affect antigens and receptors as well as the cancer cell motility and capacity to infiltrate the basement membrane and the deformability potential of metastatic cells. Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 48 Cytoskeletons in the cancer cells Actin cytoskeleton in the invasion/ metastatic process Vignjevic and Montagnac, Seminars in Cancer Biology, 2008 Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 49 Integrins and cadherins in the cancer cells Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 50 EMT in Tumor Progression Progression Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 51 Normal stroma vs tumor microenvironment (Zhang and Liu, Pharmacology and Therapeutics 137(2), 2013 Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 52 The tumor microenvironment • Neoplastic cells: i.e. cancer stem cells, cancer associated fibroblast, • Infiltrating cells: i.e. lymphocyte, macrophage, • Resident cells: i.e. fibroblasts, endothelial cells, • Secreted soluble factors Cytokines (i.e. CXCR-4 and CXCL-12, TNF-α), Matrix-altering enzymes” (i.e. matrix metalloproteinases (MMPs)) Growth factors VEGF: Vascular endothelial growth factor, FDG: Fibroblast growth factors PDGF: The platelet derived growth factor TGF-β: Transforming growth factor beta • The extracellular matrix • Hypoxia (low oxygen levels) • Acidic conditions (low pH level) • Hypoglycemia (low glucose level) • Massive cell death • Abnormal properties of surrounding cells Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 53 Hypoxia in solid tumor • Imbalance between oxygen supply and oxygen consumption in tumors B Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 54 Hypoxia-induced angiogenesis A Molecular mechanisms of tumor-associated angiogenesis. (Ref: Simpson-Haidaris et al., PPAR Research, 2010) Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 55 Blood vessels & flow in cancer cells Diagrammatic representation of the vascular system. A. Normal tissue. B. Solid tumor. Red represents well-oxygenated arterial blood, blue represents poorly oxygenated venous blood, and green represents lymphatic vessels. (Ref: Tredan et al., JNCI, 2007, 99:1441-1454) Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 56 Tumor-associated angiogenesis in tumor microenvironment A B Tumor-associated angiogenesis is sustained through stromal microenvironment crosstalk. (Ref: Simpson-Haidaris et al., PPAR Research, 2010) Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 57 Metalloproteinases (MMPs) • are metal-dependent endopeptidases • are produced by stromal cells rather than by tumor cells in many solid tumors Ref: Roy et al., JCO, 2009 Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 58 Hypoxia-induced EMT in tumor microenvironment Various factors that induce cancer cell EMT in tumor microenvironment. (Ref: Jing et al., Cell & Bioscience 2011, 1:29) Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 59 Cancer stem cells Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 60 Fibroblasts • are principal cellular component of connective tissue • synthesize ECM and collagen • are involved in the production & remodeling of the ECM • provide potentially oncogenic signals such as TGF-β and hepatocyte growth factor (HGF) to resident epithelia • stimulate cancer-cell proliferation and invasion by secreting growth factors such as TGF-β and stromal-cell-derived factor 1 (SDF1). NIH/3T3 Fibroblasts in cell culture (Ref: http://en.wikipedia.org/wiki/Fibroblast) Tumor Associated Fibroblasts Fibroblast Cell Structure & Tumor Microenvironment Tumor associated fibroblast RPN-530 Oncology for Scientist-I 62 Endothelial cells & Pericytes Pericytes are adjacent to endothelial cells and embedded within the vascular basement membrane of blood microvessels. They participate in the construction of the tumor-associated vasculature Endothelial–pericyte interactions in microvessels EC Ref: Armulik et al., Circulation Research, 2005 Pericytes - Endothelial cells signaling network can contribute to tumor development and metastasis Tumor-associated endothelial cells Function in tumor development, progression and metastasis formation and Angiogenesis/ lymphangiogenesis) Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 63 Immune inflammatory cells Many tumor-associated immune cells such as macrophages, dendritic cells, and cytotoxic T cells may either promote tumor growth and progression or protect the cancer cell from apoptosis Macrophages • are white blood cells • are crucial member of tumor stromal cells. • are phagocyte of cell debris and pathogens • function in wound healing, inflammatory response Tumor associated macrophages • • • • http://legacy.owensboro.kctcs.edu/gcaplan/ anat/histology/api%20histo %20connective.htm induce tumor growth, promote angiogenesis, enhancement of tumor cell migration and invasion, promote metastasis Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 64 Adipocytes • are in mammary gland and bone marrow • act as a energy source for the normal and cancer cells • secrete hormons, growth factors, MMPs and specific cytokines (i.e. adipokines, adiponectin, resistin, visfatin) • primarily constitute adipose tissue • are involved in tumor progression Section of tumor (mauve) in the presence of adipocytes (white discs). The arrows indicate adipocytes modified by the tumor. (Credit: Copyright G. Escourrou) Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 65 Communication of tumor cells with tumor microenvironment Intravasation Cell Structure & Tumor Microenvironment Ref: Sun et al., Cancer Metastatis Rev. 2010 RPN-530 Oncology for Scientist-I 66 SDF-1 & CXCR4 in Tumor microenvironment . EPCs: Endothelial progenitor cells Ref: Orimo and Weinberg (2006) stromal cell derived factor-SDF-1 (CXCL12) Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 67 Organ-spesific metastasis & tumor microenvironment .. Ref: Sun et al., Cancer Metastatis Rev. 2010 Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 68 Transforming growth factor beta (TGF-β) in cross talk Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 69 TGF-β and SDF-1 autocrine signaling in myofibroblast formation (Ref: Kojima et al., PNAS 2010, 107(46): 20009–20014) Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 70 Hedgehog signaling Basal cell carcinoma Normal (Smoothened) (The Suppresor of Fused) Patched domaincontaining protein Ref: Epstein, Nature Reviews Cancer 8, 2008 Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 71 Hedgehog signaling in tumor microenvironment Ref: Curran & Ng, Nature 455, 2008 Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 72 Heterotypic interactions as therapeutic targeting “Targeting the tumor microenvironment” chemokine inhibitors) Inh VE ibito sig GF, Frs of nal ing GF Cell Structure & Tumor Microenvironment Inhibitors of HGF /c-Met Inhi PDGbitors o f sign F aling Anti-inflammatory inhibitors (cytokine, Inh ma ibito trix rs o tur f no ver RPN-530 Oncology for Scientist-I 73 QUESTIONS????? [email protected] Cell Structure & Tumor Microenvironment RPN-530 Oncology for Scientist-I 74