Cancer & Cell Biology Study Guide

Cancer & Cell Biology Study Guide

DNA & Genetics

  • DNA Preservation

    • DNA is located in the nucleus of the cell.

    • It contains genetic instructions required for protein synthesis.

  • Base Pairing Rules

    • The specific pairing of nucleotides in DNA:

    • Adenine (A) matches with Thymine (T)

    • Cytosine (C) matches with Guanine (G)

  • Processes Involving DNA

    • Transcription:

    • DNA is transcribed to produce RNA in the nucleus.

    • Translation:

    • RNA is translated to form proteins within the ribosome.

  • PCR (Polymerase Chain Reaction)

    • A laboratory method that artificially replicates DNA to produce millions of copies.

  • DNA Sequencing

    • The process of determining the precise order of nucleotides within a DNA molecule.

  • Microarray Technology

    • A technique used to assess gene expression profiles; can indicate which genes are overactive or underactive, particularly relevant in cancer research.

Cell Cycle & Mitosis

  • Cell Cycle

    • The series of events that a cell undergoes as it grows and divides, consisting of phases:

    • G1 Phase: Cell growth phase

    • S Phase: DNA replication occurs

    • G2 Phase: Preparation for cell division

    • M Phase (Mitosis): The process of cell division occurs.

  • Checkpoints

    • Mechanisms that ensure the cell is ready to advance to the next stage in the cycle, e.g., verifying that DNA is undamaged.

  • Phases of Mitosis (in order)

    1. Prophase: The chromosomes condense and become visible.

    2. Metaphase: Chromosomes align in the middle of the cell.

    3. Anaphase: Sister chromatids are pulled apart to opposite ends of the cell.

    4. Telophase: Formation of new nuclei around the separated chromosomes.

    5. Cytokinesis: The cytoplasm divides, resulting in two daughter cells.

  • Chromosome Types

    • Sister Chromatids: Identical copies of a chromosome connected at the centromere.

    • Homologous Chromosomes: Chromosomes that contain the same genes but may have different alleles, one inherited from each parent.

Cancer Biology

  • Cancer Definition

    • A disease characterized by uncontrolled cell division, leading to disruption of homeostasis in the body.

  • Stages of Cancer

    • Stage 0: Abnormal cells are present, but they remain in situ (localized).

    • Stage I: Small, localized tumor is present.

    • Stage II: Larger tumor that may spread to nearby tissues.

    • Stage III: Cancer has spread to lymph nodes.

    • Stage IV: Metastasis has occurred, with the cancer spreading to other organs.

  • Oncogenes

    • Proto-oncogenes: Normal genes with roles in cell growth that can become oncogenes through mutation, thereby contributing to cancer development.

    • Angiogenesis: The process of forming new blood vessels, which tumor cells exploit to secure a blood supply.

Cancer Detection

  • Diagnostic Tools

    • Blood Tests: Can identify abnormal proteins or cells typical of cancer.

    • X-rays: Used to reveal dark spots indicative of tissue density changes that may suggest tumors.

    • CT Scan: Provides three-dimensional imaging with greater detail compared to X-rays.

    • MRI (Magnetic Resonance Imaging): Best suited for imaging soft tissues like the brain and internal organs.

    • PET Scan: Employs radioactive tracers to highlight areas with active cancer cell metabolism.

Cancer Treatments

Treatment

Description

Chemotherapy

Utilizes chemical substances to target and kill rapidly dividing cells, including cancer cells.

Radiation

Delivers high-energy rays to damage the DNA of cancer cells; also has the potential to induce cancer.

Immunotherapy

Enhances or alters the immune system to recognize and attack cancer cells; may include gene editing.

CRISPR

A precise gene-editing tool that can be employed for repairing or eliminating genes associated with cancer.

  • Types of Radiation

    • Radio Waves: Weakest form of radiation, low energy.

    • Gamma Rays: Strongest type of radiation, high energy capable of damaging DNA.

    • Sun Radiation: Includes UV rays; the ozone layer helps protect against the most harmful UV radiation.

Organ Systems and Cancer

  • Major Organ Systems:

    • Familiarization with organ systems such as circulatory, nervous, digestive, and immune systems is essential.

    • Cross-Impact of Cancer: Cancer in a specific organ system can influence the function and health of other systems, e.g., melanoma (skin cancer) may metastasize and affect other organs.

Common Misconceptions About Cancer

  • Not All Tumors are Cancerous: Distinction between benign and malignant tumors is critical.

  • Cancer is Not Always Inherited: Genetic predisposition can increase risk but is not the sole factor.

  • **Cancer Cannot be