Mitosis pt2 Cancer Control of Cell Division-1

Types of Normal Cells

• Normal RBCs: Typical red blood cells

• Normal Nerve Cells: Regular nerve cells

• Normal Fat Cells: Adipose tissue cells

• Normal Skin Cells: Standard skin cells

• Normal Sex Cells: Eggs and sperm

Characteristics of Cancer Cells

• Irregular Surface: Cancer cells often exhibit unusual shapes compared to normal cells.

• Rapid Division: Cancer cells divide uncontrollably.

Cancer Growth Patterns

• Metastasis: The process by which cancer cells spread from the original site to other parts of the body.

• Anchorage Dependence: Normal cells need a surface for division, while cancer cells do not.

• Density-Dependent Inhibition: Normal cells stop dividing when they are crowded, while cancer cells ignore this.

Skin Cancer Types

• Melanoma: Most aggressive skin cancer, compared to basal cell and squamous cell cancers.

  • ABCDs of Melanoma:

    • A: Asymmetry

    • B: Border irregularity

    • C: Color not uniform, darker areas

    • D: Diameter greater than 6 mm

    • E: Evolving size, shape, and color

Cancer Cell Division

• Cell Division Regulation:

  • Normal cells exhibit anchorage dependence and density-dependent inhibition.

  • Cancer cells bypass these regulatory mechanisms.

Uncontrolled Mitosis

• Caused by increased growth factors and exceeding the Hayflick limit (number of divisions before cell division ceases).

  • Telomere Length: Connected to the number of cell divisions. Shortened telomeres lead to cellular aging and apoptosis (programmed cell death).

Factors in Aging and Cancer

• Telomere Shortening: Loss of telomeres over time affects cell division.

• Oxidative Stress: Damage to DNA, proteins, and lipids by free radicals.

• Glycation: Glucose binds to and inhibits crucial biomolecules, impacting their function.

Genes Involved in Cancer

• Proto-oncogenes: Normal genes that can mutate to become oncogenes, promoting cell division.

• Oncogenes: Mutated genes that contribute to cancer.

• Tumor-Suppressor Genes: Genes that normally prevent uncontrolled cell division. Inactivation can lead to cancer.

Cancer Development Process

• Multistep Process: Involves multiple gene mutations over years leading to cancer progression.

• Inherited Cancer: Genetic predispositions contribute to certain cancers, such as mutations in BRCA1 and BRCA2 genes, which are linked to breast cancer risks.

Common Cancers in the U.S.

• Women: Skin, breast, lung, colorectal cancers.

• Men: Non-melanoma skin, prostate cancers.

Prostate Cancer

• Stages: Detected through PSA (prostate-specific antigen) tests; symptoms include:

  • Frequent urination

  • Difficulty urinating

  • Blood in urine

  • Pain during urination

• Treatment options include surgery, hormone therapy, and radiation.

Other Cancer Types

• Esophageal Cancer: Increasingly common among men with risk factors including tobacco use and obesity.

• Colorectal Cancer: Involves a series of genetic mutations leading to malignant growth.

Cancer Prevention

• Risk Factors: Include tobacco use, excessive alcohol consumption, and UV radiation exposure.

• Preventive Strategies: Lifestyle changes and vaccinations against certain viruses (e.g., HPV).

Cancer Awareness Initiatives

• National Breast Cancer Awareness Month (NBCAM): Founded in 1985 to promote awareness and encourage screening.