neoplasia: abnormal mass of tissue growth

Hallmarks of Cancer:

• self-sufficiency in growth signals

• insensitivity to anti-growth signals ( because they don’t have receptors)

• evading apoptosis( telomeres)

• sustained angiogenesis

• limitless replicative potential

• invasion and metastasis

• escaping immune surveillance (checkpoint inhibitors)

• variation in population of cells

• heritable: Mutations in DNA, chromosomes, methylation pattern

Terminology

• tissue types

  • carcinoma → epithelial cells

  • sarcoma → connective tissue

  • leukemia → circulatory or lymphatic

• cell types

  • adenomatous cells → ductal or glandular cells

  • squamous cells → flat cells

  • myeloid → blood cells

  • Lymphoid → lymphocytes or macrophages

• begin vs malignant

  • benign tumors → suffix “- oma”

  • except carcinomas + sarcomas + lymphomas

  • malignant → all other tumors

  • carcinoma in situ (CIS) → epithelial malignant tumors that have not broken through or invade the surrounding stroma (can be cut out cleanly)

    

Cancer Progression

• stages of malignant cancers:

  • stage 1: confined to the organ of origin

  • stage 2: locally invasive

  • stage 3: spread to lymph nodes

  • stage 4: spread to distant sites

• Tumor staging by TNM System

  • Tumor

  • Nodes

  • Metastasis

• How does cancer progress in the body( from embryo to death)?

  • fertilized egg → toti potent stem cell → proliferation(copy-paste) → differentiation (specialization) → ♾ → advantageous driver mutant → clonal expansion → saturation the point where tumor is its bigger because there is no more food/ energy/ space) → new advantageous mutant( even more aggressive) → new colonial expansion wave

  • remember:

    • limitless replicated potential ( due to enzymes that elongate the telomeres→ telomerase p53 CANCER! )

    • what is the paradox

      • fast growing tumors are easiest to treat

Tumor Markers

• → biological markers that are produced by cancer cells

  • enzymes

  • genes

  • Antigens ( PSA -prostate-specific antigens are associated with prostate cancer)

  • antibodies

Bengin vs. Malignant cancer

Viral Infection → Cancer

• PAP smear- cervical l screaming via a swab, the smear is histologically analyzed and checks if to dysplasia

  • red stained cells are dysplasia or cancer

    • could also show cells is mitosis and multiple nuclei

    • blub that starts to grow → lesion

    • HPV causes cancer in basal cells( because they proliferate the most)

      • due to the alteration of genome of the host develops cancer

      • HVP produced proteins that block p53( hallmark in cancer) if the p53 build-ups and it does not function the cell does not go into apoptosis

  • blue + purple stained cells are normal

• Other viruses can cause tumors because the disturb normal cell development

  • hepatitis B → liver

  • EBV → kissing disease ( mononucleosis) + Burkitt lymphoma

• Can bacteria cause cancer?

  • yes → Helicobacter pylori → stomach cancer