patho neoplasia

Cellular Perspective and Neoplasia NURS 6150: Advanced Pathophysiology

  • Instructors: Martha Gainer MS, APN-CFNP, Shirley K. Comer DNP, RN, JD, CNE, Georgianna M. Thomas, Ed.D., MSN, RN

Introduction

  • Cancer Definition: A group of diseases characterized by uncontrolled growth and spread of abnormal cells.
  • Statistics:
    • Second most common cause of death in the US.
    • Approximately 12 million Americans have a history of cancer.
    • In 2012, there were about 1,638,910 new cancer cases and approximately 577,190 deaths due to cancer.
  • Causes: Multiple factors interact to lead to the development of cancer.

Cellular Functions

  • Functions of Cells:
    • Movement: Ability of cells to change location.
    • Conductivity: Capacity for cells to transmit signals.
    • Metabolic Absorption: Cells absorb nutrients and other substances.
    • Secretion: Cells release products necessary for bodily function.
    • Excretion: Elimination of waste products.
    • Respiration: Cells use oxygen to produce energy.
    • Reproduction: Cells divide to create new cells.
    • Communication: Cells interact through signaling molecules.

Cellular Structure/Components

  • Protoplasm: The internal cell matrix.
  • Nucleus: Contains the genetic material.
  • Cytoskeleton: Provides structure and support for the cell.
  • Organelles:
    • Ribosomes: Protein synthesis.
    • Endoplasmic Reticulum:
    • Rough: Protein synthesis for export.
    • Smooth: Lipid synthesis and calcium storage.
    • Golgi Complex: Modifies proteins and packages them into vesicles for transport.
    • Lysosomes: Isolate and degrade cellular components.
    • Peroxisomes: Metabolize fatty acids and generate heat.
    • Proteasomes: Remove abnormal proteins in the cytoplasm and nucleoplasm, ensuring protein quality.
    • Mitochondria: Power plants of the cell, responsible for ATP production through oxidative metabolism.

Plasma Membrane/Receptors

  • Composition:
    • Wall Structure: Comprised of lipids, integral and peripheral proteins, and carbohydrates.
  • Fluid Mosaic Model: Describes the cell membrane's flexible structure with embedded proteins.
  • Cellular Receptors: Help in cellular communication and can be modulated by various factors.

Cell Functions

  • Cellular Communication:
    • Gap Junctions: Allow direct communication between neighboring cells.
    • Autocrine Signaling: Cells respond to their own signals.
    • Paracrine Signaling: Signals affect neighboring cells.
    • Endocrine Signaling: Hormones released into the bloodstream affect distant cells.
    • Synaptic Signaling: Nerve cells communicate through neurotransmitters.

Cell Cycle/Division/Metabolism

  • Cell Cycle Overview:
    • Consists of 5 phases, common in most cells:
    • G0 Phase: Inactive phase with variable duration; cells may exit the cycle.
    • G1 Phase: Preparation for cell division.
    • S Phase: Synthesis phase where DNA and centrioles replicate.
    • G2 Phase: RNA synthesis occurs preparing for mitosis.
    • M Phase: Mitosis occurs, including Prophase, Metaphase, Anaphase, and Telophase.
  • Cellular Metabolism: Includes anaerobic and aerobic processes.

Membrane Transport Principles

  • Transport Mechanics:

    • Water moves across membranes based on osmotic pressure.
    • Small uncharged, lipid-soluble particles and gases move freely depending on diffusion pressure.
    • Charged or large particles require assistance to move across membranes.

  • Passive Transport Mechanisms:

    • Diffusion: Movement of solutes.
    • Osmosis: Movement of water.
    • Facilitated Diffusion: Requires carrier proteins for solute transport.

  • Active Transport: Requires ATP to move substances against their concentration gradient, notably represented by the Na-K-ATPase pump.

  • Co-Transport Systems:

    • Symport: Carries solute and Na+ in the same direction.
    • Antiport: Carries solute and Na+ in opposite directions.

  • Endocytosis Types:

    • Pinocytosis: Cell drinking, uptake of liquid.
    • Phagocytosis: Cell eating, uptake of solid particles.
    • Receptor-mediated Endocytosis: Requires binding to a receptor.

  • Exocytosis: Process for expelling materials from the cell.

Body Tissues

  • Composition of Body Tissues: Made of specialized cells, about 200 types, falling into four basic categories:
    • Epithelial: Covers and protects body surfaces.
    • Connective: Supports and connects body structures.
    • Muscle: Responsible for movement.
    • Nervous: Facilitates communication throughout the body.

Extracellular Tissue Components

  • Cell Junctions:
    • Tight Junctions: Prevent passage of materials between cells.
    • Adhering Junctions: Connect adjacent cells maintaining structural integrity.
    • Gap Junctions: Allow for intercellular communication.
    • Hemidesmosomes: Anchor cells to the extracellular matrix