Severe failure in the regulation of genes (Mutations) that code for cell division.
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Transcript of Severe failure in the regulation of genes (Mutations) that code for cell division.
Severe failure in the regulation of genes (Mutations) that code for cell division
Cancer Characteristics• Lack Differentiation
– “Immortal” due to repeated division, normal cells do not repair the mutation
– Not Specialized = No purpose to any body part, does use nutrients from the body
• Have Abnormal Nuclei– - Genes are mutated and contain excessive number of
chromosomes• Form Tumors
– Abnormal mass of cells that invade surrounding tissues and disrupt normal cellular mitosis
Microscopic Appearance of Cancer Cells
Loss of Normal Growth Control
Cancer cell division
Fourth orlater mutation
Third mutation
Second mutation
First mutation
Uncontrolled growth
Cell Suicide or Apoptosis
Cell damage—no repair
Normal cell division
Hyperplasia
HyperplasiaNormal
Dysplasia
Hyperplasia Mild dysplasiaNormal
Carcinoma in Situ
Milddysplasia
Carcinoma in situ (severe
dysplasia) Cancer(invasive)
Normal Hyperplasia
Example of Normal Growth
Dermis
Dividing cells in basal layer
Dead cells shed from
outer surface
Epidermis
The Beginning of Cancerous Growth
Underlying tissue
Tumors (Neoplasms)
Underlying tissue
Invasion and Metastasis
3Cancer cells reinvade and grow at new location
1Cancer cells invade surrounding tissues and blood vessels
2Cancer cells are transported by the circulatory system to distant sites
Cancer• Cells divide uncontrollably and produce an excess of
tissue– Benign Tumors
• NOT cancerous. • Does not spread to other parts of the body or invade and
destroy nearby tissue. • Benign tumors usually grow slowly.• Generally, not harmful. However, this is not always the case.
If a benign tumor is big enough, its size and weight can press on nearby blood vessels, nerves, or organs, or otherwise cause problems
– Malignant tumor can be fatal• Cancer cells compete with normal cells for nutrients, blood,
and energy eventually causing normal cells to atrophy• The spreading of cancer is known as Metastasis which allows
cells to spread to other parts of the body Cancer cells usually spread via the bloodstream or the lymph system
Causation
Environmental & Genetic
Chromosomes are DNA molecules
Heredity
RadiationChemicals
Viruses
Chemicals & Radiation-Damage the genes
Virus -Introduces own genes
Heredity-Passes on alterations in genes
Mutations and Cancer
Genes Implicated in Cancer
Oncogenes are
Mutant Forms of Proto-Oncogenes
Cell proliferation driven by internal oncogene signaling
Transcription
Activated gene regulatory protein
Inactive intracellular signaling protein
Signaling protein from active oncogene
Inactive growth factor receptor
DNA Repair Genes
Cancer
No cancer
No DNA repair
Normal DNA repair
Base pair mismatch
T CATC
A GTCG
T CAGC
A GTCG
A GTG A GTAG
T CATCT CATC
Cancer Causing Viruses• HTLV-1
– Attacks killer T-cells in leukocytes and impairs Lymphatic system T-Cell Leukemia
• HIV– Directly attacks Helper T cells which are
responsible for stimulating B Lymphocytes antibody production
Epstein Barr (EBV)– Hodgkin’s Lymphoma– Burkitt’s Lymphoma
• Hepatitis B (HBV)– Liver Cancer
• Human Papillomavirus (HPV) • Cervical Cancer
• Herpes Simplex 2– Cancer of the cervix
Different Kinds of Cancer
Lung
Breast (women)
Colon
BladderProstate (men)
Some common sarcomas:Fat
Bone
Muscle
Lymphomas:Lymph nodes
Leukemias:Bloodstream
Some common carcinomas:
Naming Cancers
Prefix Meaning
adeno- gland
chondro- cartilage
erythro- red blood cell
hemangio- blood vessels
hepato- liver
lipo- fat
lympho- lymphocyte
melano- pigment cell
myelo- bone marrow
myo- muscle
osteo- bone
Cancer Prefixes Point to Location
Necrosis – Death of a cell or a group of cells
Atrophy – Decrease in cellular size and corresponding organs or tissuesNeoplasm – Abnormal formation or
growth
Common Cancer Terms
MelanomaDestruction melanocytes
LymphomaDestruction of lymph nodes
CarcinomaMalignant tumor hat arises from epithelial cells
SarcomaMuscle or connective tissue cancer
LeukemiaDestruction of Leukacytes (WBC)
Signs / Symptoms
Got Pain?1.Nerve Pressure2.Passageway Obstruction
3.Vital Organ Malfunction
• Problems with Diagnosing Cancer– Vague
• See next slide for common symptoms
– Depends on size, location, and which organs are being affected
– Asymptomatic– Symptoms can be misleading
Symptoms of CancerSubjective
Common Symptoms
• Fever• Aches• Weakness• Weight Loss• Cough• Pain• Headaches• Irritable
• Behavior Change• Inconsistent Digestion• Rash• Lumps• Skin Color Change• Mental Problems• Abnormal CBC
Signs of CancerObjective
Diagnosis• Biopsy• X-Ray• CBC• Angiography• Pap Smear• Mammogram• Colonoscopy/Endoscopy• Fecal Occult Blood Test
Biopsy – Removal and microscopic examination of tissues from the body
After cancer has been diagnosed, doctors ask the following three questions to determine how far the disease has progressed:1. How large is the tumor, and how deeply
has it invaded surrounding tissues?2. Have cancer cells spread to regional
lymph nodes?3. Has the cancer spread (metastasized)
to other regions of the body?
After cancer has been diagnosed, doctors ask
the following three questions to determine how
far the disease has progressed:1. How large is the tumor, and how deeply
has it invaded surrounding tissues?2. Have cancer cells spread to regional
lymph nodes?3. Has the cancer spread (metastasized) to
other regions of the body?
• Stage 0 – carcinoma in situ.
• Stage I – cancers are localized to one part of the body.
• Stage II – cancers are locally advanced.
• Stage III – cancers are also locally advanced. Whether a cancer is
designated as Stage II or Stage III can depend on the specific type of cancer; for example, in Hodgkin's Disease, Stage II indicates affected lymph nodes on only one side of the diaphragm, whereas Stage III indicates affected lymph nodes above and below the diaphragm. The specific criteria for Stages II and III therefore differ according to diagnosis.
• Stage IV – cancers have often metastasized, or spread to other
organs or throughout the body
Treatments
Common Cancer Treatments
• Chemotherapy• Radiation Therapy• Bone Marrow Transplant• Targeted Therapy• Immunotherapy